bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Role of Processing Speed and Cognitive Control on Word Retrieval in Aging and Aphasia
Authors: Faroqi-Shah Yasmeen , Gehman Megan 
Published: February 2021

Purpose
When speakers retrieve words, they do so extremely quickly and accurately—both speed and accuracy of word retrieval are compromised in persons with aphasia (PWA). This study examined the contribution of two domain-general mechanisms: processing speed and cognitive control on word retrieval in PWA.

Method

Three groups of participants, neurologically healthy young and older adults and PWA (
n
= 15 in each group), performed processing speed, cognitive control, lexical decision, and word retrieval tasks on a computer. The relationship between word retrieval speed and other tasks was examined for each group.

Results
Both aging and aphasia resulted in slower processing speed but did not affect cognitive control. Word retrieval response time delays in PWA were eliminated when processing speed was accounted for. Word retrieval speed was predicted by individual differences in cognitive control in young and older adults and additionally by processing speed in older adults. In PWA, word retrieval speed was predicted by severity of language deficit and cognitive control.

Conclusions
This study shows that processing speed is compromised in aphasia and could account for their slowed response times. Individual differences in cognitive control predicted word retrieval speed in healthy adults and PWA. These findings highlight the need to include nonlinguistic cognitive mechanisms in future models of word retrieval in healthy adults and word retrieval deficits in aphasia.
Hyperspectral face recognition with a spatial information fusion for local dynamic texture patterns and collaborative representation classifier
Authors: Hao Min , Liu Guangyuan , Xie Desheng 
Published: February 2021

AbstractHyperspectral face recognition provides improved classification rates due to its abundant information in the face cubes of every subject in hyperspectral face databases. However, while offering excellent opportunities, it also brings new challenges, such as low signal‐to‐noise ratio, interband misalignment, and high data dimensionality. Based on these ad hoc problems, literature has already proposed some optimisation methods including dimensionality reduction, image denoising, and alignment to perform face recognition, yet lacking comprehensive evaluation. This paper proposes a novel hyperspectral face recognition algorithm that is based on spatial information fusion for feature extraction (histogram of local dynamic texture patterns) and collaborative representation classifier for classification. Meanwhile, the algorithm is applied to three popular hyperspectral face databases, Carnegie Mellon University (CMU)‐hyperspectral face database (HSFD), University of Western Australia (UWA)‐HSFD, and Hong Kong Polytechnic University (PolyU)‐HSFD databases. Experimental results demonstrate that CMU‐HSFD and UWA‐HSFD databases achieve very competitive classification results. PolyU‐HSFD database also achieves rather good classification rates. The best recognition results are 98.5% ± 0.95, 96.6% ± 0.98, and 94.0% ± 2.86 for CMU‐HSFD, UWA‐HSFD and PolyU‐HSFD, respectively. It demonstrates experimentally that this algorithm can be used to recognise faces. Moreover, we compared eight existing state‐of‐the‐art face recognition techniques with our proposed method in performing hyperspectral face recognition. In this research, we formulate hyperspectral face recognition as an image‐set classification problem and evaluate the performances compared with other kinds of algorithms. Comparisons with the eight existing hyperspectral face recognition techniques on three standard datasets show that the proposed algorithm outperforms most other state‐of‐the‐art algorithms, indicating that it is a promising approach for hyperspectral face recognition.
Introducing a new multi-particle collision method for the evolution of dense stellar systems
Authors: Di Cintio Pierfrancesco , Pasquato Mario , Kim Hyunwoo , Yoon Suk-Jin 
Published: February 2021

Context. Stellar systems are broadly divided into collisional and non-collisional categories. While the latter are large-N systems with long relaxation timescales and can be simulated disregarding two-body interactions, either computationally expensive direct N-body simulations or approximate schemes are required to properly model the former. Large globular clusters and nuclear star clusters, with relaxation timescales of the order of a Hubble time, are small enough to display some collisional behaviour and big enough to be impossible to simulate with direct N-body codes and current hardware.
Aims. We aim to introduce a new method to simulate collisional stellar systems and validate it by comparison with direct N-body codes on small-N simulations.
Methods. The Multi-Particle Collision for Dense Stellar Systems (MPCDSS) code is a new code for evolving stellar systems with the multi-particle collision method. Such a method amounts to a stochastic collision rule that makes it possible to conserve the exact energy and momentum over a cluster of particles experiencing the collision. The code complexity scales with N log N in the number of particles. Unlike Monte Carlo codes, MPCDSS can easily model asymmetric, non-homogeneous, unrelaxed, and rotating systems, while allowing us to follow the orbits of individual stars.
Results. We evolved small (N = 3.2 × 104) star clusters with MPCDSS and with the direct-summation code NBODY6, finding a similar evolution of key indicators. We then simulated different initial conditions in the 104 − 106 star range.
Conclusions. MPCDSS bridges the gap between small collisional systems that can be simulated with direct N-body codes and large non-collisional systems. In principle, MPCDSS allows us to simulate globular clusters such as Ω Centauri and M 54, and even nuclear star clusters, which is beyond the limits of current direct N-body codes in terms of the number of particles.
Discontinuity analysis of the leading switchback transition regions
Authors: Akhavan-Tafti M. , Kasper J. , Huang J. , Bale S. 
Published: February 2021

Context.Magnetic switchbacks are magnetic structures characterized as intervals of sudden reversal in the radial component of the pristine solar wind’s magnetic field. Switchbacks comprise of magnetic spikes that are preceded and succeeded by switchback transition regions within which the radial magnetic field reverses. Determining switchback generation and evolution mechanisms will further our understanding of the global circulation and transportation of the Sun’s open magnetic flux.Aims.The present study juxtaposes near-Sun switchback transition regions’ characteristics with similar magnetic discontinuities observed at greater radial distances with the goal of determining local mechanism(s) through which switchback transition regions may evolve.Methods.Measurements from fields and plasma suites aboard the Parker Solar Probe were utilized to characterize switchback transition regions. Minimum variance analysis (MVA) was applied on the magnetic signatures of the leading switchback transition regions. The leading switchback transition regions with robust MVA solutions were identified and categorized based on their magnetic discontinuity characteristics.Results.It is found that 78% of the leading switchback transition regions are rotational discontinuities (RD). Another 21% of the leading switchback transition regions are categorized as “either” discontinuity (ED), defined as small relative changes in both magnitude and the normal component of the magnetic field. The RD-to-ED event count ratio is found to reduce with increasing distance from the Sun. The proton radial temperature sharply increases (+ 29.31%) at the leading RD-type switchback transition regions, resulting in an enhanced thermal pressure gradient. Magnetic curvature at the leading RD-type switchback transition regions is often negligible. Magnetic curvature and the thermal pressure gradient are parallel (i.e., “bad” curvature) in 74% of the leading RD-type switchback transition regions.Conclusions.The leading switchback transition regions may evolve from RD-type into ED-type magnetic discontinuities while propagating away from the Sun. Local magnetic reconnection is likely not the main driver of this evolution. Other drivers, such as plasma instabilities, need to be investigated to explain the observed significant jump in proton temperature and the prevalence of bad curvature at the leading RD-type switchback transition regions.
Spontaneous Regression of a Clival Chordoma: An Unusual Case Report
Authors: Vellutini Eduardo de Arnaldo Silva , Stamm Aldo Eden Cassol , de Oliveira Matheus Fernandes 
Published: February 2021

Abstract
Introduction Chordoma is a malignant and aggressive tumor originating from remnants of the primitive notochord and usually involving the axial skeleton. Spontaneous regression of clival chordomas was described recently. We present the third case report of spontaneous regression of a clival chordoma and discuss similarities of cases and implications for clinical practice.
Case Description We present the case of a previously healthy 21-year-old Caucasian woman who presented with progressive holocranial headache for 3 months, which encouraged image investigation. Magnetic resonance imaging (MRI) revealed an osteolytic clival lesion hyperintense in T2 and hypointense in T1 images. After 2 months of initial evaluation and surgical proposal, she repeated MRI to allow use for intraoperative neuronavigation. Surprisingly, there was tumor regression.
Discussion The present reported case is somehow different from previous ones and does not share an underlying inflammatory/immunological recognizable fact, being interpreted by us as a spontaneous partial regression of the tumor. We highlight the need for continuous investigation of chordoma regression to uncover the underlying mechanisms.
Retrosigmoid Craniectomy with a Layered Soft Tissue Dissection and Hydroxyapatite Reconstruction: Technical Note, Surgical Video, Regional Anatomy, and Outcomes
Authors: Magill Stephen T. , Lee Young M. , Rubio Roberto R. , Nguyen Minh P. , Heilman Carl B. , McDermott Michael W. 
Published: February 2021

Abstract
Introduction There are many reported modifications to the retrosigmoid approach including variations in skin incisions, soft tissue dissection, bone removal/replacement, and closure.
Objective The aim of this study was to report the technical nuances developed by two senior skull base surgeons for retrosigmoid craniectomy with reconstruction and provide anatomic dissections, surgical video, and outcomes.
Methods The regional soft tissue and bony anatomy as well as the steps for our retrosigmoid craniectomy were recorded with photographs, anatomic dissections, and video. Records from 2017 to 2019 were reviewed to determine the incidence of complications after the authors began using the described approach.
Results Dissections of the relevant soft tissue, vascular, and bony structures were performed. Key surgical steps are (1) a retroauricular C-shaped skin incision, (2) developing a skin and subgaleal tissue flap of equal thickness above the fascia over the temporalis and sub-occipital muscles, (3) creation of subperiosteal soft tissue planes over the top of the mastoid and along the superior nuchal line to expose the suboccipital region, (4) closure of the craniectomy defect with in-lay titanium mesh and overlay hydroxyapatite cranioplasty, and (5) reapproximation of the soft tissue edges during closure. Complications in 40 cases were pseudomeningocele requiring shunt (n = 3, 7.5%), wound infection (n = 1, 2.5%), and aseptic meningitis (n = 1, 2.5%). There were no incisional cerebrospinal fluid leaks.
Conclusion The relevant regional anatomy and a revised technique for retrosigmoid craniectomy with reconstruction have been presented with acceptable results. Readers can consider this technique when using the retrosigmoid approach for pathology in the cerebellopontine angle.
Anatomical Variants of Post-ganglionic Fibers within the Pterygopalatine Fossa: Implications for Endonasal Skull Base Surgery
Authors: Li Lifeng , London Nyall R. , Prevedello Daniel M. , Carrau Ricardo L. 
Published: February 2021

Abstract
Objectives The vidian nerve provides parasympathetic innervation to the nasal cavity and the lacrimal gland. Previous anatomic studies have primarily focused on preservation or severance of the vidian nerve proximal to the pterygopalatine ganglion (PPG). This study aimed to assess its neural fibers within the pterygopalatine fossa after synapsing at the PPG, and to explore potential clinical implications for endoscopic endonasal skull base surgery.
Methods An endonasal transpterygoid approach was performed on eight cadaveric specimens (16 sides). The PPG and maxillary nerve within the pterygopalatine fossa were divided. The vidian nerve was traced retrograde into the foramen lacerum, and postganglionic fibers distal to the PPG were dissected following the zygomatic nerve into the orbit. Potential communicating branches between the ophthalmic nerve (V1) and the PPG were also explored.
Results All sides showed a plexus of neural communications between the PPG and the maxillary nerve. The zygomatic nerve exits the maxillary nerve close to the foramen rotundum, piercing the orbitalis muscle to enter the orbit in all sides. The zygomatic nerve was identified running beneath the inferior rectus muscle toward a lateral direction. In 7/16 sides (43.75%), a connecting branch between V1 and the pterygopalatine ganglion was observed.
Conclusion Neural communications between the PPG and the maxillary nerve were present in all specimens. A neural branch from V1 to the PPG potentially contributes additional postganglionic parasympathetic function to the lacrimal gland.
Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio and Their Role as Predictors of Disease Severity of Coronavirus Disease 2019 (COVID-19)
Authors: Jain Rohit , Gopal Arun , Pathak Basant Kumar , Mohakuda Sourya Sourabh , Tilak TVSVGK , Singh Anchit Raj 
Published: February 2021

Abstract

Context Due to the wide spectrum of clinical illness in coronavirus disease 2019 (COVID-19) patients, it is important to stratify patients into severe and nonsevere categories. Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been evaluated rapidly by a few studies worldwide for its association with severe disease, but practically none have been conducted in the Indian population. This study was undertaken to examine the role of NLR and PLR in predicting severe disease in Indian patients.
Objectives The objective was to study the association of NLR and PLR observed at the time of admission with maximum disease severity during hospitalization and to study their role in predicting disease severity.
Material and Methods A total of 229 COVID-19 patients were admitted at the center during the study period. After applying inclusion and exclusion criteria, 191 patients were included in the study. The demographic, clinical, and laboratory (complete blood count, NLR, and PLR) data of all patients were obtained at the time of admission. Maximum disease severity of all patients was assessed during hospitalization.
Statistical Analysis Chi-square and Mann–Whitney U tests were used to assess statistical significance. Receiver operating characteristic curve (ROC) was plotted for NLR and PLR to estimate the cutoff values and sensitivity and specificity using Youden’s index for predicting severe disease. Logistic regression analysis was used to estimate the odds ratios (OR) and 95% confidence intervals.
Results Mean NLR and PLR were significantly higher in severe patients (NLR = 7.41; PLR = 204) compared with nonsevere patients (NLR = 3.30; PLR = 121). ROC analysis showed that NLR, in comparison to PLR, had a higher area under the curve (AUC) of 0.779, with a larger OR of 1.237 and cutoff of 4.1, and showed 69% sensitivity and 78% specificity in predicting severe disease. Cut off for PLR was 115.3, which showed 79% sensitivity and 62% specificity in predicting severe disease.
Conclusion NLR and PLR, both showing acceptable AUCs, can be used as screening tools to predict disease severity. However, NLR was a better predictor of disease severity.
SARS-CoV-2 Infection during Pregnancy in a Rural Midwest All-delivery Cohort and Associated Maternal and Neonatal Outcomes
Authors: Steffen Haley A. , Swartz Samantha R. , Jackson J. Brooks , Kenne Kimberly A. , Ten Eyck Patrick P. , Merryman Abbey S. , Castaneda Claire N. , Marsden Katharine , Maxwell Timothy , Merrill Anna E. , Krasowski Matthew D. , Rysavy Mary B. 
Published: February 2021

Objective This study aimed to estimate the prevalence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) among pregnant patients at the time of delivery in a rural Midwest tertiary care hospital and to examine demographics, clinical factors, and maternal and neonatal outcomes associated with SARS-CoV-2 infection during pregnancy.
Study Design This prospective cohort study included all delivering patients between May 1 and September 22, 2020 at the University of Iowa Hospitals and Clinics. Plasma SARS-CoV-2 antibody testing was performed. SARS-CoV-2 viral reverse-transcription polymerase chain reaction (RT-PCR) results and maternal and neonatal outcomes were collected from the electronic medical record. Data were analyzed using univariate statistical methods with clustering for multiple births.
Results In total, 1,000 patients delivered between May 1 and September 22, 2020. Fifty-eight (5.8%) were SARS-CoV-2 antibody positive. Twenty-three also tested viral positive during pregnancy. Three of 1,000 (0.3%) were viral positive on admission but antibody negative. The median age was 30 years (interquartile range [IQR]: 26–33 years) and body mass index was 31.75 kg/m2 (IQR 27.7–37.5 kg/m2). The cesarean delivery rate was 34.0%. The study population was primarily white (71.6%); however, 41.0% of SARS-CoV-2 infected patients identified as Black, 18.0% as Hispanic/Latino, 3.3% as Native Hawaiian/Pacific Islander, and only 27.9% as White (p < 0.0001). SARS-CoV-2 infection was more likely in patients without private insurance (p = 0.0243). Adverse maternal and/or neonatal outcomes were not more likely in patients with evidence of infection during pregnancy. Two SARS-CoV-2 infected patients were admitted to the intensive care unit. There were no maternal deaths during the study period.
Conclusion In this largely rural Midwest population, 6.1% of delivering patients had evidence of past or current SARS-CoV-2 infection. Rates of SARS-CoV-2 during pregnancy were higher among racial and ethnic minorities and patients without private insurance. The SARS-CoV-2 infected patients and their neonates were not found to be at increased risk for adverse outcomes.
Key Points
Influence of Alveolar Fluid on Aquaporins and Na+/K+-ATPase and Its Possible Theoretical or Clinical Significance
Authors: Zong Hai-Feng , Guo Guo , Liu Jing , Yang Chuan-Zhong , Bao Lin-Lin 
Published: February 2021

Objective Pulmonary edema is the most common pathophysiological change in pulmonary disease. Aquaporins (AQPs) and Na+/K+-ATPase play pivotal roles in alveolar fluid clearance. This study aimed to explore the influence of increased alveolar fluid on the absorption of lung fluid.
Study Design Eighty New Zealand rabbits were randomly divided into eight groups (n = 10 in each group), and models of different alveolar fluid contents were established by the infusion of different volumes of normal saline (NS) via the endotracheal tube. Five animals in each group were sacrificed immediately after infusion to determine the wet/dry ratio, while the remaining animals in each group were killed 4 hours later to determine the wet/dry ratio at 4 hours. Additionally, lung specimens were collected from each group, and quantitative real-time PCR (qRT-PCR), western blot, and immunohistochemical (IHC) analyses of AQPs and Na+/K+-ATPase were performed.
Results The qRT-PCR analysis and western blot studies showed markedly decreased mRNA and protein levels of AQP1 and Na+/K+-ATPase when the alveolar fluid volume was ≥6 mL/kg, and the mRNA level of AQP5 was significantly reduced when the alveolar fluid volume was ≥4 mL/kg. In addition, IHC analysis showed the same results. At 4 hours, the lung wet/dry ratio was significantly increased when the alveolar fluid volume was ≥6 mL/kg; however, compared with 0 hours after NS infusion, there was still a significant absorption of alveolar fluid for a period of 4 hours.
Conclusion The results of this study suggest that increased alveolar fluid may induce the downregulation of the mRNA and protein expression of AQPs and Na+/K+-ATPase, which appear to affect alveolar fluid clearance in rabbit lungs. Early intervention is required to avoid excessive alveolar fluid accumulation.
Key Points
A Study of CD44 Positive Cancer Cells in Epithelial Ovarian Cancer and their Correlation with P53 And Ki67
Authors: Kar Ketaki , Ghosh Suman , Roy Anup Kumar 
Published: February 2021

Abstract
Context  Epithelial ovarian carcinomas are one of the most common lethal gynecological malignancies. There is no specific symptom or biomarker for detection of this malignancy in early stage. So, the advanced stage, nature of frequent recurrences, and resistance to chemotherapies make it very difficult to deliver proper treatment to patients. Efforts are on to identify the presence of cancer stem cell by using a specific biomarker in epithelial ovarian cancer in the early stage.
Objectives  This study aims to identify the CD44 positive cancer cells in epithelial ovarian carcinoma of different histopathological types. It also intends to correlate the expression of CD44 with the expression of p53 and Ki67.
Materials and Methods Sections from diagnosed specimens of ovarian epithelial neoplasm had been fixed in 10% formalin and embedded in paraffin, and they were used for immunohistochemical (IHC) staining for CD44, p53, and Ki67, using a peroxidase kit with mouse monoclonal antibodies. Then, the slides were evaluated for both tumor cell percentage and intensity of immunoreactivity.
Statistical Analysis Chi-square had been used to find the significance of study. Significance level was considered at p value < 0.05
Results  In this study, 40 patients were included in a period of one and a half years. The present study suggested that the levels of CD44 expression were increased in epithelial ovarian cancer compared to borderline tumor. CD44 was positively correlated with the ki67 expression and tumor grade. High-grade serous, mucinous, and endometrioid tumors were associated with high CD44 expression. Positivity of CD44 was found significantly higher in case of positive status of p53 (z = 3.65; p < 0.0001).
Conclusion We can correlate CD44 positive cancer stem cells with grade of ovarian carcinomas, but for prognostic significance and therapeutic applications, more corroborative and multicentric works in this field are needed. CD44 can be targeted for therapy in recurrent and resistant cases of ovarian cancer.
Interference caused by electromagnetic interactions
Authors: Kolokolov A.A. 
Published: February 2021

Abstract
We consider interference fluxes of energy, momentum and angular momentum, describing the interaction of electric charges with constant and variable electromagnetic fields. Absorption and stimulated emission of atoms in the field of free and evanescent waves are described. It is shown that in the case of interaction with reactive fields, the momentum of an atom during absorption and stimulated emission does not change. A wave derivation of Planck’s formula based on the interference of the fields of classical thermal radiation and quantum zero-point oscillations is presented.