bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated quantitation of 18F-flurpiridaz PET MPI and its diagnostic performance of coronary artery disease
Authors: Builoff V , Lemley M , Fujito H , Miller R J H , Ramirez G , Kavanagh P , Buckley C , Berman D , Slomka P
Published: June 2024

Background/Introduction

18F-flurpiridaz, a novel positron emission tomography (PET) myocardial perfusion (MPI) imaging tracer, has shown efficacy in the detection of obstructive coronary artery disease (CAD) and is anticipated to be adopted in clinical practice soon. This post-hoc analysis of the 18F-flurpiridaz phase III clinical trial (NCT01347710) investigates the diagnostic performance of fully automated quantitative analysis by QPET software (Cedars-Sinai, Los Angeles, California, United States) for stress total perfusion deficit (S_TPD) and ischemic total perfusion deficit (I_TPD), compared to expert reader assessments in the detection of obstructive coronary artery disease (CAD) defined as stenosis ≥70%.

Purpose

The current standard method for interpreting PET MPI images involves visual assessment by a physician, which is inherently subjective and prone to high inter-reader variability. Quantification improves reproducibility of PET MPI evaluation.

Methods

This study retrospectively analyzes 753 cases from the original trial data, calculating area under the receiver operating characteristic curve (AUC) for S_TPD and I_TPD, and compares these values with summed stress scores (SSS) and summed difference scores (SDS) provided by three expert readers (R1, R2, R3), accounting for repeated readings as in the original trial, to evaluate diagnostic accuracy. Normal databases for this analysis were developed using 15 patients from the Phase II trial. Contours were verified by an experienced technologist. All other processing was fully automated.

Results

The contours were corrected in 2.4% stress and 4.4% rest cases. The AUC values for the readers’ SSS for stenosis ≥70% were found to be 0.812 (95% confidence interval [CI] 0.778 – 0.846) for R1, 0.801 (95% CI 0.766 – 0.836) for R2, and 0.828 (95% CI 0.795 – 0.860) for R3, compared to 0.812 (95% CI 0.778 – 0.846) for automatically quantified S_TPD (Figure 1A). The AUC values for the readers’ SDS for stenosis ≥70% were found to be 0.789 (95% CI 0.753 – 0.826) for R1, 0.780 (95% CI 0.744 – 0.816) for R2, and 0.798 (95% CI 0.761 – 0.834) for R3, compared to 0.813 (95% CI 0.778 – 0.848) for I_TPD (Figure 1B). Sensitivity of automated S_TPD quantification was 87% (95% CI 81% - 91%) and specificity was 57% (95% CI 52% - 61%) (Figure 2A). Sensitivity of I_TPD quantification was 83% (95% CI 77% - 87%) and specificity was 62% (95% CI 58% - 66%) (Figure 2B). Almost all quantitative results were similar to the readers’ results (p = NS), except for the comparison of AUC for I_TPD to SDS for R2, where I_TPD was higher (p = 0.04) (Figure 1B).

Conclusion

Quantitative analysis is comparable to expert reader evaluations in detecting ≥70% stenosis in CAD but can be derived consistently and automatically. The incorporation of TPD quantitative measures could standardize and potentially enhance the diagnostic process for obstructive CAD.
The diagnostic value of 18F-FDG PET/CT in suspected native valve endocarditis - a terciary center experience
Authors: Costa G , Batista G , Monteiro E , Guimaraes J , Fernandes D , Goncalves L , Vieira M J
Published: June 2024

Background

Infective endocarditis (IE) is difficult to diagnose accurately, especially for native valve endocarditis (NVE) and prosthetic material-related infection (PVE). The aim of this study is to evaluate the diagnostic performance of 18F-FDG PET in patients with suspected IE referred for PET/CT imaging.

Purpose

This retrospective study aims to assess the diagnostic value of 18F-FDG PET/CT for suspected NVE.

Methods

Data were collected from all patients who underwent 18F-FDG PET/CT for suspected IE at a tertiary center between May 2016 and January 2022. The final diagnosis of IE was established by consulting the Endocarditis team's diagnosis at the time of hospital discharge or death, after considering clinical, microbiological, and imaging information as well as clinical response. Sensitivity, specificity, and positive and negative predictive values of 18F-FDG PET/CT in diagnosing NVE were estimated.

Results

The study included 87 patients, of whom 32 had suspected NVE. The mean age was 62 +/- 19 years, and 62% were male. Of the patients with suspected NVE, 56% were male, with a median age of 53.5 (IQR 41.5-71) years. Fever was present in 84% of patients, and 16% had signs of heart failure. Laboratory tests showed a mean CRP of 16.2 mg/dL and a mean leucocyte count of 10.9 G/L. Among the suspected NVE patients, 8 had a definitive diagnosis of IE, with compatible findings observed in 18F-FDG PET/CT for 5 patients. The calculated sensitivity and specificity of 18F-FDG PET/CT for diagnosing NVE were 62.5% and 100%, respectively.

Conclusion

18F-FDG PET/CT appears to be highly specific but not very sensitive for diagnosing NVE.
[82Rb] biodistribution and radiation dosimetry in a pediatric population
Authors: Kamani C H , Gnesin S , Di Bernardo S , Dietz M , Allenbach G , Dolan M , Sekarski N , Prior J
Published: June 2024

Introduction

There is no established recommendation on the use of [82Rb] PET/CT in the paediatric population and a lack of [82Rb] dosimetry data in this population. We aimed to estimate paediatric dosimetry based on adult biokinetic data and prospectively acquired paediatric biokinetic data.

Materials and methods

Organ absorbed doses (OAD) and effective doses (E) were estimated using ICRP-103 based OLINDA/EXM 2.1 software. We calculated paediatric OAD and E from image-derived biokinetic data (OADp,Ab and Ep,Ab respectively) according to age groups. [82Rb] EANM paediatric dosage card cluster and the recommended administered activity were then determined. Ten paediatric participants (M:F 7:3; mean age 8.8±6.6) underwent dynamic rest and stress 3D-SiPM [82Rb] PET/CT scans. Using PMOD software, source organs volumes were delineated to obtain source organ time activity curves and participant specific organ masses based on PET/CT data to derive subject-specific OAD (OADp and Ep respectively) data.

Results

[82Rb] was assigned to the EANM PDC B-Cluster. Estimated ranges for Ep,Ab resp. Ep were 2.19E-02; 1.15E-03, resp. 9.62E-03; 1.04E-03 mSv/MBq. Ep,Ab after a single [82Rb] infusion was between 0.5–0.7 mSv, similar to Ep from for 3D PMT (0.4–0.8 mSv), while Ep was reduced by 0.2–0.4 mSv for 3D SiPM PET/CT. The most irradiated organs were the kidneys and the heart wall in infant and new-born group, followed by heart wall in the other age groups, hence, the small intestine, pancreas, lungs, adrenals, and rest of the gastrointestinal tract. [82Rb] PET/CT was safe and well-tolerated by all participants.

Conclusion

We firstly provide original dosimetry data for the use of [82Rb] PET/CT in the paediatric population, showing reasonably low radiation exposure, and confirming safety and tolerability of [82Rb] PET/CT in this population. Based on our estimations, we provided recommendations for the insertion of [82Rb] in the EANM Paediatric Dosage Card.
Evaluation of myocardium metabolism by PET-CT on hypertrophic cardiomyopathy
Authors: Alves P , Fernandes C R , Silva R , Gomes A , Abrunhosa A , Castelo-Branco M , Goncalves L , Ferreira M J
Published: June 2024

Background

Hypertrophic cardiomyopathy is defined as the presence of increased left ventricle (LV) myocardial wall thickness (MWT) not solely explained by loading conditions. Myocardial metabolism can be assessed by PET-CT with 2-[18F]FDG. The purpose of this study was to assess myocardial LV wall metabolism and features related with non-obstructive HCM with normal LV ejection fraction, namely, MWT, left atrium volume (LAV) and biochemical markers of LV dysfunction (NT-proBNP) and the score of sudden cardiac death (SCD)

Methods and Results

Thirty patients were recruited with an age of 54.4±11.3, 60% males and with a MWT of 20.3±4.3 and an LAV of 46.1±16.5 and a NT-proBNP of 661.2±724.2. PET-CT was performed in a Biograph Vision 600, Siemens and to suppress physiologic 2-[18F]FDG cardiac uptake, a 2 day high-fat/low-carbohydrate diet and a 12 hours overnight fast were prescribed. Increased 2-[18F]FDG myocardial uptake (increased metabolism) was considered when above the vascular activity (threshold ≥ 1) and presented as a percentage of LV myocardium. Areas of increased metabolism were seen in 60% of the patients with an extension of 19.1± 24.0. MWT, LAV and NT-proBNP were significantly correlated with 2-[18F]FDG uptake with a correlation coefficient of 0.39 (p=0.03) 0.43 (p=0.02), 0.51(p=0.01), respectively.

Conclusions

Increased metabolism in the wall of the LV seems to have a role on phenotype expression of the disease and on myocardial dysfunction
Is there a link between cancer and atherosclerotic cardiovascular disease?
Authors: Fernandes R , Borges-Rosa J , Silva R , Costa G , Goncalves L , Ferreira M J
Published: June 2024

Background

Atherosclerotic cardiovascular disease (ACVD) is a major cause of morbidity and mortality around the world. Women bellow 50 years are almost, invariably, of low risk. There is an overlap of biological mechanisms between ASCVD and cancer.

Purpose

The main purpose of this study was to evaluate inflammatory activity in the aorta of young women with breast cancer before treatment and relate it with total metabolic tumor volume (MTV) and age.

Methods

This was a retrospective study that included consecutive women under 55 years without diabetes or other significant cardiovascular risk factors for ACVD that underwent 2-[18F]FDG PET-CT for breast cancer staging before treatment. To assess the metabolic activity in the aorta the maximum lesion tissue-to-background ratio (TBR) was recorded for each segment.

Results

44 patients were included, with a mean age of 42.9 ± 7.45 years and a total median MTV of 5.67 ± 45.1 cm3. Spearman correlation was used, and the results are displayed in table 1.

Conclusion

Metabolic/inflammatory activity in the abdominal aorta wall was related with tumor metabolic activity but not with age. In this young group of breast cancer women, the metabolic/inflammatory activity of both conditions seemed to be linked.
Macrophage depletion delays infiltration of inflammatory macrophages into the infarct area after myocardial infarction in mice
Authors: Hess A , Strunk M , Willmann M , Ross T L , Bengel F M , Thackeray J T
Published: June 2024

Background/Introduction

Myeloid-derived inflammatory macrophages expressing CCR2 are crucial for scar formation and repair after myocardial infarction (MI). Interference with macrophage dynamics impairs healing and promotes intraventricular thrombus formation, but the precise dynamics of CCR2 macrophages in the left ventricle (LV) under these conditions remain unclear.

Purpose

We investigated the impact of macrophage depletion on infarct CCR2 expression, microcalcification, and cardiac functional outcome in mice after reperfused MI.

Methods

Male and female C57BL/6N mice underwent 60 min ischemia/reperfusion MI (n=24) or sham (n=8) 24h after injection of clodronate-liposomes (n=8m, 8f) for macrophage depletion, or PBS-liposomes (n=8m, 8f). Infarct CCR2 expression was measured on MI+4d by 68Ga-ECL1i PET. Microcalcification was assessed by 18F-NaF PET/CT at 4wks. MRI and 99mTc-tetrofosmin SPECT calculated LV function and infarct sizes at 6wks.

Results

Acute mortality was markedly higher after macrophage depletion within 7d of MI compared to PBS (%, 37.5 vs 0). Infarct CCR2 expression was significantly increased in macrophage depletion MI vs sham on d4 (%injected dose (ID)/g; 0.39±0.13 vs 0.25±0.05; p=0.005), but similar between PBS MI and sham (ID/g; 0.31±0.06, p=0.1), indicating rapid repopulation of peripheral monocytes after single time macrophage depletion, and delayed infiltration into injured myocardium. There were no sex dependent differences in infarct CCR2 expression. Infarct size after MI was 25.9±9.3 %LV with no difference between treatments. LV ejection fraction at 6wks was significantly reduced after MI vs sham, but comparable between treatments (%; clodronate: 33±9 vs PBS: 37±8 vs sham 66±5, p<0.001). Heart weight at 6wks was significantly increased only in macrophage depleted MI compared to sham (heart weight/body weight (mg/g); 5.5±0.8 vs 4.6±0.4, p=0.02). Male macrophage-depleted mice and 50% of female mice exhibited a dense intracavity thrombus adherent to the infarct wall after MI, which showed significantly higher 18F-NaF uptake at 4wks compared to PBS MI (%ID/g; 6.0±4.9 vs 0.4±0.3; p<0.001), highlighting necessity of timely infiltration of the infarct with inflammatory macrophages for adequate cardiac repair.

Conclusion

By 4d after reperfused MI, the myocardium exhibits signs of inflammation resolution and decline of CCR2+ cell content in mice. Single time macrophage depletion prior to MI delays but does not prevent infiltration of CCR2+ inflammatory macrophages into infarct territories. Male mice are at higher risk of LV thrombus formation, demonstrating sex dependent differences in cardiac repair, which seem to be independent from the amount of CCR+ macrophages.
Feasibility of 68Ga-FAPI-46 PET for evaluating fibrosis activity in aortic aneurysm
Authors: Paeng J , Suh H Y , Kim Y K , Choi J W
Published: June 2024

Purpose

Fibroblast activation protein (FAP) expression is upregulated in tissue fibrosis, active inflammation, and tumors. Aortic aneurysm (AA) is a disease where aortic wall loses its elasticity with fibrotic change. We investigated the feasibility of 68Ga-labelled FAP inhibitor (FAPI) PET and its quantitative indexes, as a non-invasive imaging for evaluating fibrosis activity in AA.

Methods

Twenty patients with AA who were planned for aneurysmal resection were prospectively enrolled. 68Ga-FAPI-46 PET was preoperatively performed to examine FAP expression in the AA. Nine 68Ga-FAPI-46 PET cases from lung cancer patients were used as control. Expressions of FAP and other markers in the resected AA tissue and remote aorta were assessed by western blotting. 68Ga-FAPI-46 PET was evaluated visually, and quantitatively using SUV and target-to-liver ratio (TLR). The image findings and quantitative indexes were compared with the clinicopathologic factors.

Results

When AA tissues were divided into tertiles according to the visual grading of PET, the quantitative indexes showed significant differences among groups (Low 2.07±0.36 vs. Moderate 2.80±0.47 vs. High 3.55±0.37, p=0.002 for SUVmax; Low 2.37±0.57 vs. Moderate 2.81±1.16 vs. High 4.44±0.13, p=0.042 for TLR). Quantitative indexes of FAPI PET were significantly higher in AA patients compared to control group (1.99±0.36 vs. 2.51±0.67, p=0.048 for SUVmax; 2.10±0.71 vs. 2.81±1.03, p=0.038 for TLR). On western blotting, the AA tissue showed variable but overall increased FAP expression compared to the remote aorta (p=0.012). The quantitative indexes of FAPI PET were significantly correlated with the degree of FAP expression on western blotting (rho=0.75, p=0.0020 for SUVmax; rho=0.68, p=0.0070 for TLR). CT growth rate was significantly different among groups (Low -0.0051±0.011 vs. Moderate 0.0074±0.00947 vs. High 0.034±0.043, p=0.037) and positive correlation was found between CT growth rate and SUVmax (rho=0.53, p=0.043). No significant correlation was found between the indexes and other markers including smooth muscle proliferation (a-SMA) or inflammation (TGF-b).

Conclusion

AA tissues show variable but overall increased FAP expression. The quantitative indexes of FAPI PET are well correlated with the FAP expression on the tissue. FAPI PET can be an effective non-invasive imaging for evaluating fibrosis activity of AA, and further studies are warranted to assess clinical implication of fibrosis activity in the AA.
Whitewashing American Exceptionalism: Racialized Subject-Positioning and US Foreign Policy
Authors: Maass Richard W
Published: June 2024

Abstracts

American exceptionalism is enjoying a revival of scholarly interest amid new approaches to studying foreign policy narratives and unease regarding how US policymakers will manage a less unipolar international system. That revival coincides temporally, though not yet substantively, with growing attention to racialized dynamics and Eurocentrism within international relations. This article examines how core strands of American exceptionalism—the prevailing narrative framing of US foreign policy—reflect a whitewashed understanding of US foreign policy that can best be understood as the product of racialized subject-positioning that saturated its historical development. After conceptualizing American exceptionalism, it develops a theoretical framework to capture how racialized subject-positioning stratifies understandings of a nation’s role in the world. It proceeds to investigate how this process shaped the development of American exceptionalism in line with epistemologies of immanence, ignorance, and innocence, producing exceptionalist narratives that neglect non-white populations as meaningful others in the construction of US national identity and that negate US interactions with those groups as relevant evidence that might undercut its exceptionalism. These whitewashing effects remained embedded even as overtly racist discourse became delegitimized, posing enduring obstacles for US diplomacy today.
A primer for quantum computing and its applications to healthcare and biomedical research
Authors: Durant Thomas J S , Knight Elizabeth , Nelson Brent , Dudgeon Sarah , Lee Seung J , Walliman Dominic , Young Hobart P , Ohno-Machado Lucila , Schulz Wade L
Published: June 2024

Objectives

To introduce quantum computing technologies as a tool for biomedical research and highlight future applications within healthcare, focusing on its capabilities, benefits, and limitations.

Target Audience

Investigators seeking to explore quantum computing and create quantum-based applications for healthcare and biomedical research.

Scope

Quantum computing requires specialized hardware, known as quantum processing units, that use quantum bits (qubits) instead of classical bits to perform computations. This article will cover (1) proposed applications where quantum computing offers advantages to classical computing in biomedicine; (2) an introduction to how quantum computers operate, tailored for biomedical researchers; (3) recent progress that has expanded access to quantum computing; and (4) challenges, opportunities, and proposed solutions to integrate quantum computing in biomedical applications.
Heteroplasmy Is Rare in Plant Mitochondria Compared with Plastids despite Similar Mutation Rates
Authors: Khachaturyan Marina , Santer Mario , Reusch Thorsten B H , Dagan Tal
Published: June 2024

Plant cells harbor two membrane-bound organelles containing their own genetic material—plastids and mitochondria. Although the two organelles coexist and coevolve within the same plant cells, they differ in genome copy number, intracellular organization, and mode of segregation. How these attributes affect the time to fixation or, conversely, loss of neutral alleles is currently unresolved. Here, we show that mitochondria and plastids share the same mutation rate, yet plastid alleles remain in a heteroplasmic state significantly longer compared with mitochondrial alleles. By analyzing genetic variants across populations of the marine flowering plant Zostera marina and simulating organelle allele dynamics, we examine the determinants of allele segregation and allele fixation. Our results suggest that the bottlenecks on the cell population, e.g. during branching or seeding, and stratification of the meristematic tissue are important determinants of mitochondrial allele dynamics. Furthermore, we suggest that the prolonged plastid allele dynamics are due to a yet unknown active plastid partition mechanism. The dissimilarity between plastid and mitochondrial novel allele fixation at different levels of organization may manifest in differences in adaptation processes. Our study uncovers fundamental principles of organelle population genetics that are essential for further investigations of long-term evolution and molecular dating of divergence events.
How “baked in” ideas hinder ideational robustness: the International Monetary Fund and “fiscal space”
Authors: Clift Ben
Published: June 2024

This paper brings insights into ideational robustness to bear on the International Monetary Fund (IMF) fiscal policy thinking. It advances understanding of both the IMF and the concept of ideational robustness by focusing on economic ideas as they are put into practice by expert economic institutions. The IMF has traditionally enjoyed a reputation as a hawkish enforcer of neoliberal doctrine and conservative fiscal discipline, foregrounding deficit bias and fiscal sustainability concerns. Capitalist crises, notably the 2008 crash and COVID, have seen public debt increase while rendering growth and stability increasingly elusive. This turbulence has spurred some rethinking of Fund fiscal ideas. The IMF has added the new concept of fiscal space to its policy commentary and advocacy. Fiscal space seeks to reconcile economic stabilization and supporting growth to the Fund’s overarching concern to maintain fiscal discipline and sustainability. A focus on how ideas are put into practice shows that long-standing Fund fiscal priorities are hardwired into operational frameworks, curtailing the new emphasis and adaptions. Thus, key to the institutional conditions of IMF fiscal policy actions are “baked in” economic ideas. These are operationalized through economic models, analytical tools, fiscal evaluation frameworks, and standard operating procedures. The “politics of economic method,” in the form of deliberation and contestation over different normative ideas that can underpin alternative constructions of such policy frameworks, plays an important role in shaping which economic ideas come to matter, and how, for the IMF. The Fund’s “fiscal space” episode can be interpreted as a quest for ideational robustness (through increased flexibility), which thus far remains unrealized due to the crucial role of these mechanisms, institutional conditions, and ideational path dependencies.
Exposure to family and domestic violence in the prenatal period is associated with an increased risk of hospitalization for bronchiolitis in children under 2 years
Authors: Orr Carol , Kelty Erin , Belinelo Patricia , Fisher Colleen , Glauert A Rebecca , O’Donnell Melissa , Preen David B
Published: June 2024

Background

Existing research has acknowledged a correlation between stress in pregnancy and poorer respiratory health in offspring. However, research focusing on stress caused by family and domestic violence in the prenatal period is missing.

Methods

A retrospective cohort study included children born 1987–2010 who were identified as being exposed to FDV in the prenatal period (n = 1477) from two sources: WA Police Information Management System and WA Hospital Morbidity Data Collection (HMDC) and a non-exposed comparison group (n = 41 996). Hospitalization for bronchiolitis was identified in HMDC. Cox regression was used to estimate the adjusted and unadjusted hazard ratio and 95% confidence interval for bronchiolitis hospitalizations contact.

Results

Children exposed to FDV had a 70% (HR 1.70, 95% CI: 1.49–1.94) increased risk of hospitalization for bronchiolitis than non-exposed counterparts by age two. Children exposed to FDV had a longer average hospital stay for bronchiolitis than non-exposed children (4.0 days vs. 3.8 days, P < 0.001).

Conclusions

Prenatal exposure to FDV is associated with bronchiolitis hospitalization in children <2 years. Along with other risk factors, clinicians should give consideration to maternal stress factors, including experiencing FDV as a potential contributor to bronchiolitis.
The United States Stereotactic EEG Survey: Current Practice and Future Opportunities
Authors: Gavvala Jay R.
Published: June 2024

Purpose:

Stereotactic EEG (SEEG) is being increasingly used in the intracranial evaluation of refractory epilepsy in the United States. A 2022 survey of SEEG practices among National Association of Epilepsy Centers tertiary referral (NAEC level IV) centers found largely similar practices across institutions. However, a few significant differences were noted in technical and patient care practice, and in the level of SEEG background training. In the year since publication, we review the identified challenges facing SEEG practice and suggest specific corrective action.

Conclusions:

Stereotactic EEG has rapidly become the principal method for intracranial EEG monitoring in epilepsy surgery centers in the United States. The rate of adoption of SEEG is currently higher than the growth of invasive monitoring overall. Most report similar indications for SEEG, although significant variability exists in personnel expertise and technical and patient care practice. Consensus statements, guidelines, and review of postgraduate training curricula are urgently needed to benchmark SEEG practice and develop appropriate skillsets in the next generation of practitioners in the United States.
Visualizing lipid nanoparticle trafficking for mRNA vaccine delivery in non-human primates
Authors: Buckley Maureen , Araínga Mariluz , Maiorino Laura , Pires Ivan S. , Kim B.J. , Michaels Katarzyna Kaczmarek , Dye Jonathan , Qureshi Kashif , Zhang Yiming , Mak Howard , Steichen Jon M. , Schief William R. , Villinger Francois , Irvine Darrell J
Published: June 2024

mRNA delivered using lipid nanoparticles (LNPs) has become an important subunit vaccine modality, but mechanisms of action for mRNA vaccines remain incompletely understood. Here, we synthesized a metal chelator-lipid conjugate enabling positron emission tomography (PET) tracer labeling of LNP/mRNA vaccines for quantitative visualization of vaccine trafficking in live non-human primates (NHPs). Following i.m. injection, we observed LNPs distributing through injected muscle tissue, simultaneous with rapid trafficking to draining lymph nodes (dLNs). Deltoid injection of LNPs mimicking human vaccine administration led to stochastic LNP delivery to 3 different sets of dLNs. LNP uptake in dLNs was confirmed by histology, and cellular analysis of tissues via flow cytometry identified antigen-presenting cells as the primary cell type responsible for early LNP uptake and mRNA translation. These results provide insights into the biodistribution of mRNA vaccines administered at clinically relevant doses, injection volumes, and injection sites in an important large animal model for vaccine development.
Evolution of iGluR ligand specificity, polyamine regulation, and ion selectivity inferred from a placozoan Epsilon receptor
Authors: Singh Anhadvir , Zhorov Boris S. , Yanez-Guerra Luis A. , Aleotti Alessandra , Yanartas C. Defne , Song Yunqi , Senatore Adriano
Published: June 2024

Epsilon ionotropic glutamate receptors (iGluRs) belong to a recently described sub-family of metazoan receptors that is distinct from the AMPA, Kainate, Delta, and Phi (i.e., AKDF) sub-family, the NMDA sub-family, and the Lambda subfamily. Here, we sought to better understand the evolutionary and functional properties of Epsilon receptors by focusing on homologues from the basal invertebrateTrichoplax adhaerens(phylum Placozoa). We provide an updated species-guided phylogeny of eukaryotic iGluRs, and a comprehensive phylogeny of placozoan receptors uncovering marked diversification of Epsilon receptors within three conserved subclades, and four invariable subclades of AKDF receptors. Detailed functional characterization of theT. adhaerensEpsilon receptor GluE1αA revealed robust activation by glycine, alanine, serine, and valine, but not glutamate. Through combined of structural modeling and mutation experiments, we used GluE1αA to test the hypothesis that only a small set of amino acids in the ligand binding domain determine ligand selectivity. Mutation of just three amino acids converted GluE1αA selectivity to glutamate, resulted in nascent sensitivity to AMPA, and increased sensitivity to the AMPA/Kainate receptor blocker CNQX. Lastly, combined modeling and mutation experiments revealed that an atypical serine residue in the pore NQR site of GluE1αA, along with an aspartate four amino acids downstream, confers sensitivity to voltage-dependent polyamine block, while the serine alone diminishes both polyamine block and Ca2+permeation compared to asparagine and glutamine residues of AMPA and Kainate receptors. Altogether, we demonstrate conserved molecular determinants for polyamine regulation between Epsilon and AKDF receptors, and evidence that natural variations in NQR residues have important implications for ion permeation and regulation by polyamines.
Potential diagnostic biomarkers for human mesenchymal tumors, especially LMP2/b1i and cyclin E1 differential expression
Authors: Tanabe Yuriko , Hayashi Takuma , OKada Mako , Aburatani Hiroyuki , Abiko Kaoru , Konishi Ikuo
Published: June 2024

Objectives: Most mesenchymal tumors found in the uterine corpus are benign tumors; however, uterine leiomyosarcoma is a malignant tumor with unknown risk factors that repeatedly recurs and metastasizes. In some cases, the histopathologic findings of uterine leiomyoma and uterine leiomyosarcoma are similar and surgical pathological diagnosis using excised tissue samples is difficult. It is necessary to analyze the risk factors for human uterine leiomyosarcoma and establish diagnostic biomarkers and treatments. Female mice deficient in the proteasome subunit low molecular mass peptide 2 (LMP2)/b1i develop uterine leiomyosarcoma spontaneously. Methodology: Out of 334 patients with suspected uterine mesenchymal tumors, patients diagnosed with smooth muscle tumors of the uterus were selected from the pathological file. To investigate the expression status of biomarker candidate factors, immunohistochemical staining was performed with antibodies of biomarker candidate factors on thin-cut slides of human uterine leiomyosarcoma, uterine leiomyoma, and other uterine mesenchymal tumors. Results: In human uterine leiomyosarcoma, there was a loss of LMP2/b1i expression and enhanced cyclin E1 and Ki-67 expression. In human uterine leiomyomas and normal uterine smooth muscle layers, enhanced LMP2/b1i expression and the disappearance of the expression of E1 and Ki-67 were noted. The pattern of expression of each factor in other uterine mesenchymal tumors was different from that of uterine leiomyosarcoma. Conclusions: LMP2/b1i, cyclin E1, and Ki-67 may be candidate factors for biomarkers of human uterine leiomyosarcoma. Further large-cohort clinical trials should be conducted to establish treatments and diagnostics for uterine mesenchymal tumors.
Dark matter scattering constraints from observations of stars surrounding Sgr A*
Authors: John Isabelle , Leane Rebecca K. , Linden Tim
Published: June 2024

High-resolution infrared data have revealed several young stars in close proximity to Sgr A*. These stars may encounter extremely high dark matter densities. We examine scenarios where dark matter scatters on stellar gas, accumulates in stellar cores, and then annihilates. We study the stars S2, S62, S4711, and S4714 and find three observable effects. First, dark matter interactions can inhibit star formation close to Sgr A*, favoring scenarios where these stars migrate into the Galactic Center. Second, dark matter interactions can delay main sequence evolution, making stars older than they appear. Third, very high dark matter densities can inject enough energy to disrupt main sequence stars, allowing S-star observations to constrain the dark matter density near Sgr A*.

Published by the American Physical Society
2024
Climate change and climate-linked finance
Authors: Turvey Calum G. , Mastrianni Morgan Paige , Liu Shuxin , Gong Chenyan
Published: June 2024

Purpose

This paper investigates the relationship between climate finance and climate ergodicity. More specifically the paper examines how climate ergodicity as measured by a mean-reverting Ornstein–Uhlenbeck process affects the value of climate-linked bonds.

Design/methodology/approach

Bond valuation is evaluated using Monte Carlo methods of the Ornstein–Uhlenbeck process. The paper describes climate risk in terms of the Hurst coefficient and derives a direct linkage between the Ornstein–Uhlenbeck process and the Hurst measure.

Findings

We use the Ornstein–Uhlenbeck mean reversion relationship in its OLS form to estimate Hurst coefficients for 5 × 5° grids across the US for monthly temperature and precipitation. We find that the ergodic property holds with Hurst coefficients between 0.025 and 0.01 which implies increases in climate standard deviation in the range of 25%–50%.

Practical implications

The approach provides a means to stress-test the bond prices to uncover the probability distribution about the issue value of bonds. The methods can be used to price or stress-test bonds issued by firms in climate sensitive industries. This will be of particular interest to the Farm Credit System and the Farm Credit Funding Corporation with agricultural loan portfolios subject to spatial climate risks.

Originality/value

This paper examines bond issues under conditions of rising climate risks using Hurst coefficients derived from an Ornstein–Uhlenbeck process.
A new energy-saving block and invisible multiribbed frame structure
Authors: Li Shengcai , Lin Jianqing , Lin Wencong , Zheng Jianying , Tu Yanzhou , Zheng Jiansheng
Published: June 2024

Purpose

Based on the conceptual design of seismic resistance in buildings, this study aims to put forward a new construction structure energy-saving block structure with invisible multiribbed frame.

Design/methodology/approach

The structure is composed of energy-saving block wall panels with invisible multiribbed frames, lightweight partition wall plates and cast-in-place reinforced concrete floor slabs. The structure design is simple and the construction is convenient and fast. The comprehensive economic index of the structure is better than that of brick-and-concrete composite construction. The self-weight of the energy-saving blocks that make up the wall is only about 25% of that of solid clay bricks. The thermal insulation and energy-saving effects of the structure can meet the national energy-saving requirements of buildings.

Findings

This new structure meets the requirements of national technology and economy, wall deformation, thermal insulation and energy-saving, and can be used mainly for multistory and mid- to high-rise residential buildings. For the core components of the new structure energy-saving block and invisible multiribbed frame composite wall, as the axial compression ratio increases in the test parameters range, the peak bearing capacity and ductility of the wall increase and the initial stiffness of the wall decreases. The axial compression ratio has a significant effect on the energy dissipation capacity of the wall. The displacement ductility coefficients ν are all greater than 2, indicating the optimal seismic performance of the wall.

Originality/value

This structure is a new, economical, lightweight, energy-saving, seismic resistant, multistory and mid- to high-rise structure that fully conforms to national conditions.
The interplay of team-level leader-member exchange and artificial intelligence on information systems development team performance: a mediated moderation perspective
Authors: Ali Ahsan , Xue Xianfang , Wang Nan , Yin Xicheng , Tariq Hussain
Published: June 2024

Purpose

The aim of this study is to investigate how team-level leader-member exchange (LMX) and the instrumental use of artificial intelligence (AI) by team members influence team psychological empowerment and information systems development (ISD) team performance.

Design/methodology/approach

A survey approach was employed to collect time-lagged, multi-source data for testing the proposed model of this study (N = 514 responses from 88 teams). PROCESS macro was used to analyze the data to generate empirical results.

Findings

The results suggest that instrumental AI use indirectly influences ISD team performance by enhancing team psychological empowerment. Additionally, it moderates the effects of team-level LMX on team psychological empowerment and ISD team performance. Furthermore, the results demonstrate that the interaction effect of LMX and instrumental AI use on ISD team performance is mediated by team psychological empowerment.

Originality/value

While research on ISD consistently demonstrates that teams, data, and technology collectively contribute to the success of these projects. What is less known, however, is how the exchange relationship between ISD teams and their leader, as well as technological factors, contribute to ISD projects. This study draws on LMX theory to propose how team-level LMX and the instrumental use of AI by team members influence team psychological empowerment and ISD team performance. The study puts forth a mediated moderation model to develop a set of hypotheses. It offers valuable contributions to AI and LMX, along with implications for ISD team management.
What drives household credit in France?
Authors: Xidonas Panos , Thomakos Dimitris , Samitas Aristeidis , Lekkos Ilias , Triantafillou Annie
Published: June 2024

Purpose

Who applies for credit, who is credit constrained and who receives credit refusal in France? To address these questions and explore the determinants of certain household credit aspects in France, we exploit a unique dataset from the Household Finance and Consumption Survey (HFCS) led by European Central Bank (ECB).

Design/methodology/approach

The anonymized dataset we utilize is based on the third survey wave (2017) and includes 13,555 French households. More specifically, considering a large number of household variables, associated with dimensions such as demographics, employment, income, wealth, assets and expenditures, we estimate three logit regression models, attempting to capture the factors that determine the underlying behavior of households.

Findings

We find that variables such as age, education, housing status, employment situation, wealth and evolution of expenses, play a key role and enter with high statistical significance in the estimated models. Our results are consistent with the existing body of literature, also offering further implications about the research questions we pose. Finally, we provide an elaborate discussion which meticulously clarifies the qualitative dimension of our findings.

Originality/value

To the best of our knowledge, no studies appear in the international literature, focusing on household credit in France, utilizing original data from the ECB.
Regenerative nature-based tourism: tour guides and stakeholder dynamics in Arctic Norway
Authors: Omma Frida Marie
Published: June 2024

Purpose

The research paper aims to explore how tour guides can contribute to regenerative tourism and the ways in which natureculture guiding practices align with stakeholder interests and the perspectives of tourism futures.

Design/methodology/approach

The ethnographic study used a multispecies approach to nature-based tourism in Arctic Norway and Sápmi, incorporating a Sámi methodology and non-human relationality.

Findings

The tour guides recognise that they are part of a more-than-human world and practice ethics that are responsible for their relations to non-human actors. Transformative experiences that are active learning opportunities can strengthen a sense of care within the tourists and pose as potential regenerative incomes in local communities, instead of extractive industries. Local knowledge and Sámi ways of being have a vital role in the tour guides' natureculture practices, which can revitalise cultural heritage and strengthen Indigenous empowerment.

Practical implications

The article suggests that tourism management and local governments must prioritise the support of tour guide initiatives involving restorative properties for socio-ecological systems. Citizen science and cultural activities are some ways that can generate a thriving ecosystem and create meaningful interactions between local communities and tourists.

Originality/value

The research highlights the unique role of tour guides as intermediaries who can translate regenerative principles into action, communicate the essence of place and take part in innovative collaborations. Tour guide practices align with the stakeholder view that tourism futures should benefit the communities and respect ecological limits.
Are negative reviews the order terminators? An aspect-based sentiment threshold analysis of online reviews in the context of sharing accommodation
Authors: Wang Bo , Jin Xin , Ma Ning
Published: June 2024

Purpose

Existing research has predominantly concentrated on examining the factors that impact consumer decisions through the lens of potential consumer motivations, neglecting the sentiment mechanisms that propel guest behavioral intentions. This study endeavors to systematically analyze the underlying mechanisms governing how negative reviews exert an influence on potential consumer decisions.

Design/methodology/approach

This paper constructs an “Aspect-based sentiment accumulation” index, a negative or positive affect load, reflecting the degree of consumer sentiment based on affect infusion model and aspect-based sentiment analysis. Initially, it verifies the causal relationship between aspect-based negative load and consumer decisions using ordinary least squares regression. Then, it analyzes the threshold effects of negative affect load on positive affect load and the threshold effects of positive affect load on negative affect load using a panel threshold regression model.

Findings

Aspect-based negative reviews significantly impact consumers’ decisions. Negative affect load and positive affect load exhibit threshold effects on each other, with threshold values varying according to the overall volume of reviews. As the total number of reviews increases, the impact of negative affect load diminishes. The threshold effects for positive affect load showed a predominantly U-shaped course of change. Hosts respond promptly and enthusiastically with detailed, lengthy text, which can aid in mitigating the impact of negative reviews.

Originality/value

The study extends the application of the affect infusion model and enriches the conditions for its theoretical scope. It addresses the research gap by focusing on the threshold effects of negative or positive review sentiment on decision-making in sharing accommodations.
Reconfiguring gender, kinship, and spirituality: space‐ and place‐making in Muslim Malaysia
Authors: Thimm Viola
Published: June 2024

In the public and private spaces of Malaysia's capitalist cities, Malay women abide by a stricter Islamic dress code than they do in rural areas. Hence, in this local context, spatial public/private and ‘placial’ rural/urban order are of importance for gender identifications and practices. These orders imply influences on gendered forms of embodiment in the form of dress codes. This research examines the sociocultural constitutions of space and place in Malaysia regarding their relatedness to one another. The central argument states (1) that public space in Muslim contexts is defined as a social space in which men and women who are eligible to marry (non‐mahram) encounter each other; and (2) that these relations are perceived and practised differently in urban and rural public and private spaces. This implies that the public‐private divide is based significantly on gendered kinship relations: that is, concepts of family.
Inequality in Denmark, 1987–2021
Authors: Leth‐Petersen Søren , Sæverud Johan
Published: June 2024

We investigate the progression of income inequality in Denmark over the years 1987–2021. During this time, we observe a consistent rise in inequality in household disposable income. This rise is influenced by shifts at both the high and low ends of the income spectrum, despite the fact that inequality in gross earnings remained unchanged up until 2008. The growing inequality in household disposable income coincides with various policy reforms aimed at enhancing incentives for employment. These changes include the reduction of the marginal tax rate on earned income and a decrease in the generosity of unemployment benefits and other forms of social assistance. At the same time, Denmark has experienced a noticeable increase in immigration, particularly from non‐Western countries and Eastern Europe. Immigrants, who rely more heavily on social transfers, find themselves increasingly at the lower income levels. Our analysis underscores that while the policy reforms were designed to encourage employment, they have also led to heightened inequality in disposable income.
Components of the evolution of income inequality in Sweden, 1990–2021
Authors: Karimi Arizo , Lucke Charlotte , Palme Mårten
Published: June 2024

This paper documents how the inequality of household equivalent disposable income has changed in Sweden over the period 1990–2021. We find that income inequality has unambiguously increased. Measured by the Gini coefficient, inequality increased from around 0.19 to almost 0.3 by the end of 2020. We then analyse the backgrounds to this change by measuring the importance of changes in different components of the overall income distribution: the wage distribution; the distribution of hours of work; capital incomes; income differences between labour market participants and non‐participants; income redistribution through income taxes and benefits; and, finally, the effect of increased immigration to Sweden.
Changing patterns of inequality in Norway: the roles of gender, education, immigration and unions
Authors: Bennett Patrick , Salvanes Kjell
Published: June 2024

We assess the evolution of inequality over time in Norway and the underlying factors which determine such changes. Inequality is low in Norway, and remains relatively unchanged from 1980 to 2019. However, these aggregate measures mask persistent inequalities across sex, education and immigrant status. Among men, inequality increases from 1980 while the opposite is true for women. Low‐educated workers fare increasingly worse over time relative to middle‐ and high‐educated workers. Despite this, the earnings of women lag behind those of lower‐educated men and considerable gender gaps exist. While immigration increases considerably, immigration itself does not drive the rise in inequality among men. Decomposing the importance of unions for earnings reveals that the declining importance of unionisation for earnings among men in the bottom half of the distribution may be an important factor behind rising inequality.