bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Gaussian process regression accelerated multiscale model for conduction-radiation heat transfer in periodic composite materials with temperature-dependent thermal properties
Authors: Tong Zi-Xiang , Li Ming-Jia , Gu Zhaolin , Yan Jun-Jie , Tao Wen-Quan 
Published: September 2022

AbstractPrediction of the coupled conduction-radiation heat transfer in composite materials with periodic structure is important in high-temperature applications of the materials. The temperature dependence of thermal properties complicates the problem. In this work, a multiscale model is proposed for the conduction-radiation heat transfer in periodic composite materials with temperature-dependent thermal properties. Homogenization analysis of the coupled conduction and radiative transfer equations is conducted, in which the temperature dependence of thermal properties is considered. Both the macroscopic homogenized equations and the local unit cell problems are derived. It is proved that the macroscopic average temperature can be used in the unit cell problems for the first-order corrections of the temperature and radiative intensity, and the calculations of effective thermal properties. The temperature dependence of thermal properties only influences the higher-order corrections. A multiscale numerical method is proposed based on the analysis. The Gaussian process (GP) regression is coupled into the multiscale algorithm to build a correlation between thermal properties and temperature for the macroscale iterations and prevent the repetitive solving of unit cell problems. The GP model is updated by additional solutions of unit cell problems during the iteration according to a variance threshold. Numerical simulations of conduction-radiation heat transfer in composite with isotropic and anisotropic periodic structures are used to validate the proposed multiscale model. It is found that the accuracy and efficiency of the multiscale method can be guaranteed by using a proper variance threshold for the GP model. The multiscale model can provide both the average temperature and radiative intensity fields and their detailed fluctuations due to the local structures.
Diagnostic utility of three Tesla diffusion tensor imaging in prostate cancer: correlation with Gleason score values
Authors: Abouelkheir Rasha Taha , Aboshamia Yasmin Ibrahim , Taman Saher Ebrahim 
Published: September 2022

Abstract
Background
Preoperative assessment of prostate cancer (PCa) aggressiveness is a prerequisite to provide specific management options. The Gleason score (GS) obtained from prostatic biopsy or surgery is crucial for the evaluation of PCa aggressiveness and personalized treatment planning. Diffusion tensor imaging (DTI) provides valuable information about microstructural properties of prostatic tissue. The most common prostate DTI measures are the fractional anisotropy (FA) and median diffusivity (MD) can give more information regarding the biophysical characteristics of prostate tissue. We aimed to explore the correlation of these DTI parameters with GS levels in PCa patients that can affect the management protocol of PCa.

Results
The computed area under curve (AUC) of the FA values used to differentiate cancer patients from control group was (0.90) with cutoff point to differentiate both groups were ≥ 0.245. The computed sensitivity, specificity, positive and negative predictive values were (84%, 80%, 95.5%, and 50%), respectively, with accuracy 83.3%. FA showed high positive correlation with Gleason score (p value < 0.001). Median diffusivity (MD) showed negative correlation with GS with statistically significant results (p value  = 0.013). PCa fiber bundles were dense, orderly arranged, without interruption in the low grade, and slightly disorganized in the intermediate group. However, in the high-grade group, the fiber bundles were interrupted, irregularly arranged, and absent at the site of cancerous foci.

Conclusions
Combined quantitative parameter values (FA and MD values) and parametric diagrams (FA and DTI maps) can be utilized to evaluate prostate cancer aggressiveness and prognosis, helping in the improvement of the management protocol of PCa patients.
Is Desmopressin Useful in the Evaluation of Cushing Syndrome?
Authors: Castinetti Frederic , Lacroix André 
Published: September 2022

AbstractThe desmopressin test was first described 30 years ago. Based on the differential secretagogue properties of desmopressin on adrenocorticotropin (ACTH) release between normal and corticotroph tumor cells, this test was intended to facilitate the diagnosis of Cushing syndrome (CS). The distinct expression of the various arginine vasopressin receptors between normal pituitary, corticotroph tumors, or neuroendocrine tumors cells secreting ACTH ectopically suggested that this test could facilitate the etiological diagnosis of ACTH-dependent CS. In this review, we analyze the merits and pitfalls of desmopressin use in the diagnostic procedures of CS. Desmopressin response is not able to completely differentiate the various etiologies of CS; its wider availability has allowed its use for inferior petrosal sinus sampling confirmation of a pituitary source of ACTH excess. In addition, desmopressin can be useful to demonstrate adequate corticotroph tumor resection when its stimulatory effect is lost following pituitary surgery of patients with Cushing disease. Desmopressin response can also be a marker of the risk of longer-term postoperative recurrence. However, this review also highlights the lack of consensual criteria of normal or abnormal response to desmopressin in its various uses and requirement for further research on its usefulness.
Clinical Use of Raman Spectroscopy Improves Diagnostic Accuracy for Indeterminate Thyroid Nodules
Authors: Palermo Andrea , Sodo Armida , Naciu Anda Mihaela , Di Gioacchino Michael , Paolucci Alessio , di Masi Alessandra , Maggi Daria , Crucitti Pierfilippo , Longo Filippo , Perrella Eleonora , Taffon Chiara , Verri Martina , Ricci Maria Antonietta , Crescenzi Anna 
Published: September 2022

Abstract

Background and Objective
Molecular analysis of thyroid fine-needle aspiration (FNA) specimens is believed to improve the management of indeterminate nodules. Raman spectroscopy (RS) can differentiate benign and malignant thyroid lesions in surgically removed tissues, generating distinctive structural profiles. Herein, the diagnostic performance of RS was tested on FNA biopsies of thyroid gland.

Design
Prospective, blinded, and single-center study.

Methods
We enrolled 123 patients with indeterminate or more ominous cytologic diagnoses (TIR3A-low-risk indeterminate lesion, TIR3B-high-risk indeterminate lesion, TIR4-suspicious of malignancy, TIR5-malignant). All subjects were surgical candidates (defined by international guidelines) and submitted to FNA procedures for RS analysis. We compared RS data, cytologic findings, and final histologic assessments (as reference standard) using various statistical techniques.

Results
The distribution of our study population was as follows: TIR3A:37, TIR3B:32, TIR4:16, and TIR5:38. In 30.9% of patients, histologic diagnoses were benign. For predicting thyroid malignancy in FNA samples, the overall specificity of RS was 86.8%, with 86.5% specificity in indeterminate cytologic categories. In patients with high-risk ultrasound categories, the specificity of RS increased to 87.5% for TIR3A, reaching 100% for TIR3B. Benign histologic diagnoses accounted for 72.9% of patients classified as TIR3A and 31.3% of those classified as TIR3B. Based on positive RS testing, unnecessary surgery was reduced to 7.4% overall (TIR3A-33.3%, TIR3B-6.7%).

Conclusions
This premier use of RS for thyroid cytology confirms its role as a valuable diagnostic tool and a valid alternative to molecular studies, capable of improving the management of indeterminate nodules and reducing unnecessary surgery.
Suboccipital Craniectomy for an Anterior Foramen Magnum Meningioma—Optimization of Resection Using Intraoperative Augmented Reality: 2-Dimensional Operative Video
Authors: Matsoukas Stavros , Oemke Holly , Lopez Laura Salgado , Gilligan Jeffrey , Tabani Halima , Bederson Joshua B. 
Published: September 2022

Foramen magnum meningiomas represent a challenge in skull base surgery because they frequently implicate the lower cranial nerves, brainstem, and posterior cerebral circulation, including the anterior spinal arteries.
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The use of virtual reality allows for surgical rehearsal based on patient-specific anatomy, thus increasing the surgeon's confidence and assists with bone opening planning by generating navigation-integrated templates.
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In this 2-dimensinal operative video, the authors demonstrate the importance of augmented reality (AR) template for the resection of a large intradural anterior foramen magnum meningioma in a 68-year-old patient. Preoperative MRI and virtual reality were used to delineate and define the extent of the tumor, as well as its relationship with nearby vital structures. The lesion measured 4.5 by 2 by 3 cm in the craniocaudal, anteroposterior and transverse axes, respectively, and was causing significant mass effect on the brainstem and spinal cord. Both vertebral arteries had a very close relationship with the tumor. After performing a bilateral craniectomy with a right side far lateral extension, debulking started at the inferior and continued toward the middle portion of the tumor. The most challenging part of the operation was to identify and protect the anterior spinal arteries, for which the AR-assisted preview of the surgical microscope proved of paramount importance. Following the heads-up display of the AR, the lateral portion of the tumor, which was adherent to the ventral surface of the vertebral artery, and then the uppermost portion of the tumor were removed, achieving a gross total resection. Appropriate consent was obtained.
Images at 4:10 used with permission. Left from Matsushima T,
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©2015; Right from Dhandapani et al,
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©2014.
Hypoxia induces an early primitive streak signature, enhancing spontaneous elongation and lineage representation in gastruloids
Authors: López-Anguita Natalia , Gassaloglu Seher Ipek , Stötzel Maximilian , Bolondi Adriano , Conkar Deniz , Typou Marina , Buschow René , Veenvliet Jesse V. , Bulut-Karslioglu Aydan 
Published: September 2022

ABSTRACT
The cellular microenvironment, together with intrinsic regulators, shapes stem cell identity and differentiation capacity. Mammalian early embryos are exposed to hypoxia in vivo and appear to benefit from hypoxic culture in vitro. Yet, how hypoxia influences stem cell transcriptional networks and lineage choices remain poorly understood. Here, we investigated the molecular effects of acute and prolonged hypoxia on embryonic and extra-embryonic stem cells as well as the functional impact on differentiation potential. We find a temporal and cell type-specific transcriptional response including an early primitive streak signature in hypoxic embryonic stem cells mediated by HIF1α. Using a 3D gastruloid differentiation model, we show that hypoxia-induced T expression enables symmetry breaking and axial elongation in the absence of exogenous WNT activation. When combined with exogenous WNT activation, hypoxia enhances lineage representation in gastruloids, as demonstrated by highly enriched signatures of gut endoderm, notochord, neuromesodermal progenitors and somites. Our findings directly link the microenvironment to stem cell function and provide a rationale supportive of applying physiological conditions in models of embryo development.
Combating COVID-19 in Ghana using socio-pedagogical methods: educational campaign through children’s arts
Authors: Manful Esmeranda , Gyasi-Boadu Nelson , Osei Mavis , Laezer Katrin Luise 
Published: September 2022

Background: This brief report presents an action research project that was conducted in 2020 to contribute to approaches to ensure adherence to COVID-19 health protocols by children in Ghana. The research was on the basis that when adults allow children to share the burden of finding effective measures to the adherence of COVID-19 health protocols, the spread of the virus will be contained, which would also ensure the safety of children. Method: The action research was designed to be socially engaging, therefore a qualitative approach using Arts-Based-Research was adopted. Arts, as a socio-pedagogical method, was used as a tool to engage 189 children, between the ages of 4 and 15 years, in art workshops in Kumasi, Ghana’s second-largest city. The children, from different socioeconomic backgrounds, were aided by Art Assistants to handle the different art materials. Results: The different artistic depiction of children on COVID-19 suggests that the awareness created had reached many children irrespective of their socioeconomic background. However, how it was portrayed by the child participants introduced a fun aspect enabling the art materials to be used for advocacy. Conclusion: The medium, children’s art, used was innovative and caught the attention of children and adults alike, hence the art materials were effective advocacy materials. Also, the flexibility of the project design enabled the researchers to adapt the outputs to suit the rapidly evolving COVID-19 issues in the country to make the project more effective.
Do Prime Brokers Matter in the Search for Informed Hedge Fund Managers?
Authors: Aragon George O. , Chung Ji-Woong , Kang Byoung Uk 
Published: September 2022

Using the setting of funds of hedge funds (FoFs), we show that prime brokers (PBs) facilitate investors’ search for informed hedge fund managers. We find that FoFs exhibit PB bias, a disproportionate preference for hedge funds serviced by their connected PBs. This PB bias is stronger when the cost of hedge fund due diligence is higher relative to capital and when the FoF’s management firm generates higher prime brokerage fees. PB bias also predicts FoF performance: the highest PB-bias quartile outperforms the rest by 2.08%–2.45% per annum after adjusting for differences in their risks. This paper was accepted by Victoria Ivashina, finance. Funding: Chung and Kang acknowledge funding support from Korea University (the Asian Institute of Corporate Governance and the Insung Research Grant) and Hong Kong Polytechnic University [Grant G-YBTG], respectively. Supplemental Material: The data files are available at https://doi.org/10.1287/mnsc.2022.4536 .
Overbooking with Bounded Loss
Authors: Freund Daniel , Zhao Jiayu (Kamessi) 
Published: September 2022

We study a classic problem in revenue management: quantity-based, single-resource revenue management with no-shows. In this problem, a firm observes a sequence of T customers requesting a service. Each arrival is drawn independently from a known distribution of k different types, and the firm needs to decide irrevocably whether to accept or reject requests in an online fashion. The firm has a capacity of resources B and wants to maximize its profit. Each accepted service request yields a type-dependent revenue and has a type-dependent probability of requiring a resource once all arrivals have occurred (or be a no-show). If the number of accepted arrivals that require a resource at the end of the horizon is greater than B, the firm needs to pay a fixed compensation for each service request that it cannot fulfill. With a clairvoyant that knows all arrivals ahead of time, as a benchmark, we provide an algorithm with a uniform additive loss bound, that is, its expected loss is independent of T. This improves upon prior works achieving [Formula: see text] guarantees. Funding: The authors gratefully acknowledge generous support by the Sloan School of Management at MIT. Supplemental Material: The online appendix is available at https://doi.org/10.1287/moor.2022.1293 .
Corporate Hierarchy and Organizational Learning: Member Turnover, Code Change, and Innovation in the Multiunit Firm
Authors: Joseph John , Rhee Luke , Wilson Alex James 
Published: September 2022

This study examines how recombinant innovation is affected by member turnover and organizational learning within a corporate hierarchy. Prior work has overlooked the role of organizational structure in organizational learning, focusing instead on the knowledge provided by individual new hires or on the disruption caused by individual departures. We address this gap by applying March’s [March JG (1991) Exploration and exploitation in organizational learning. Organ. Sci. 2(1):71–87.] mutual learning model to a corporate hierarchy. In doing so, we theorize how the contributions of corporate staff to socializing new employees and to learning from the organizational code may differ from those of the organization’s subunit members. Empirically, we examine the learning effects of aggregate corporate and subunit arrivals and departures on novel recombinant innovation by subunits. Using 24 years of Motorola company directories, we construct membership turnover measures for corporate and subunit employees and exploit patent data to capture recombinant innovation. Our results suggest that, whereas the influx of new ideas through arrivals may be critical, breaking the pattern of inertial behavior through departures is more important for recombinant innovation. Corporate departures matter most for recombinant innovation, a result that reflects not only corporate staff’s slower individual learning from the organizational code but also its ability to update that code more quickly. In supplementary analyses, we find different effects for technical and nontechnical staff and internal and external arrivals, as well as demonstrate the mutual learning mechanism using internal corporate documents to capture code change. Our study has strong implications for theories of organizational learning, strategic human capital, organization design, and innovation. Supplemental Material: The online appendices are available at https://doi.org/10.1287/orsc.2022.1618 .
Testing microbiome associations with survival times at both the community and individual taxon levels
Authors: Hu Yingtian , Li Yunxiao , Satten Glen A. , Hu Yi-Juan 
Published: September 2022

BackgroundFinding microbiome associations with possibly censored survival times is an important problem, especially as specific taxa could serve as biomarkers for disease prognosis or as targets for therapeutic interventions. The two existing methods for survival outcomes, MiRKAT-S and OMiSA, are restricted to testing associations at the community level and do not provide results at the individual taxon level. An ad hoc approach testing each taxon with a survival outcome using the Cox proportional hazard model may not perform well in the microbiome setting with sparse count data and small sample sizes.MethodsWe have previously developed the linear decomposition model (LDM) for testing continuous or discrete outcomes that unifies community-level and taxon-level tests into one framework. Here we extend the LDM to test survival outcomes. We propose to use the Martingale residuals or the deviance residuals obtained from the Cox model as continuous covariates in the LDM. We further construct tests that combine the results of analyzing each set of residuals separately. Finally, we extend PERMANOVA, the most commonly used distance-based method for testing community-level hypotheses, to handle survival outcomes in a similar manner.ResultsUsing simulated data, we showed that the LDM-based tests preserved the false discovery rate for testing individual taxa and had good sensitivity. The LDM-based community-level tests and PERMANOVA-based tests had comparable or better power than MiRKAT-S and OMiSA. An analysis of data on the association of the gut microbiome and the time to acute graft-versus-host disease revealed several dozen associated taxa that would not have been achievable by any community-level test, as well as improved community-level tests by the LDM and PERMANOVA over those obtained using MiRKAT-S and OMiSA.ConclusionsUnlike existing methods, our new methods are capable of discovering individual taxa that are associated with survival times, which could be of important use in clinical settings.
Antibiotic susceptibility patterns of pathogens isolated from laboratory specimens at Livingstone Central Hospital in Zambia
Authors: Mwansa Thresa N. , Kamvuma Kingsley , Mulemena John Amos , Phiri Christopher Newton , Chanda Warren 
Published: September 2022

Background
Multidrug resistance (MDR) is a global problem that require multifaceted effort to curb it. This study aimed to evaluate the antibiotic susceptibility patterns of routinely isolated bacteria at Livingstone Central Hospital (LCH).

Methods
A retrospective study was performed on all isolated organisms from patient specimens that were processed from January 2019 to December 2021. Specimens were cultured on standard media and Kirby-Bauer disc diffusion method was employed for susceptibility testing following the Clinical and Laboratory Standard Institute’s recommendations.

Results
A total of 765 specimens were processed and only 500 (65.4%) met the inclusion criteria. Of the 500, 291(58.2%) specimens were received from female and from the age-group 17–39 years (253, 50.6%) and 40–80 years (145, 29%) in form of blood (331, 66.2%), urine (165, 33%) and sputum (4, 0.8%). Amongst the bacterial isolates, Staphylococcus aureus (142, 28.4%) was the commonest followed by Escherichia coli (91, 18.2%), and Enterobacter agglomerans (76, 15.2%), and Klebsiella pneumoniae (43, 8.6%). The resistance pattern revealed ampicillin (93%) as the least effective drug followed by oxacillin (88%), penicillin (85.6%), co-trimoxazole (81.5%), erythromycin (71.9%), nalidixic acid (68%), and ceftazidime (60%) whereas the most effective antibiotics were imipenem (14.5%), and piperacillin/tazobactam (16.7%). The screening of methicillin resistant Staphylococcus aureus (MRSA) with cefoxitin showed 23.7% (9/38) resistance.

Conclusion
Increased levels of MDR strains and rising numbers of MRSA strains were detected. Therefore, re-establishing of the empiric therapy is needed for proper patient management, studies to determine the levels of extended spectrum beta lactamase- and carbapenemase-producing bacteria are warranted.