bluuebunny/crossref_metadata_2025 huggingface dataset:
Association and mediation pathways of maternal hyperglycaemia and liability to gestational diabetes with neonatal outcomes: A two‐sample Mendelian randomization study
Authors: He Baoting , Lam Hugh Simon , Qiu Xiu , Shen Songying , Luo Shan , Slob Eric A. W. , Au Yeung Shiu Lun
Published: November 2024

Aims

Maternal hyperglycemia is linked to adverse neonatal outcomes. However, current evidence was insufficient for mechanistic pathways. We aim to use two‐sample Mendelian randomization (MR) to obtain a comprehensive understanding of the causal association and mediation pathways.

Materials and Methods

Genetic variants of fasting glucose (FG), insulin sensitivity index (ISI), glycated haemoglobin (HbA1c), gestational diabetes mellitus (GDM) and type 2 diabetes (T2D) were used as instruments (N = 50 404–898 130). The associations with offspring birthweight, gestational duration, spontaneous preterm and post‐term birth were assessed by the inverse‐variance weighted method, using summary statistics of European genome‐wide association studies (N = 131 279–210 248). Sensitivity analyses, including multivariable MR removing pleiotropic effect from maternal body mass index (BMI), assessed the robustness. Mediation via placental weight and maternal hypertension were assessed via a two‐step MR design.

Results

FG (0.46 SD per mmol/L, 95% confidence interval [95% CI]: 0.32, 0.61) and GDM liability (0.18 SD per log odds, 95% CI: 0.08, 0.18) were positively associated with birthweight, with consistent findings for HbA1c, T2D liability and ISI. These associations were mediated by placental weight (proportion mediated: 32.8% to 77.7%). Higher HbA1c, GDM and T2D liability were associated with preterm birth (odds ratios for GDM: 1.07, 95% CI: 1.01, 1.14) and shorter gestational duration, whilst the association for T2D attenuated after adjusted for maternal BMI and gestational hypertension.

Conclusion

Maternal hyperglycemia is associated with higher birthweight (possibly indicating macrosomia), mediated via increased placental growth. GDM and T2D liability are related to preterm birth, whilst the association for T2D liability is driven by maternal adiposity.
Current State of Professionalism Curriculum in Oral Health Education
Authors: Nasseripour Melanie , Agouropoulos Andreas , Van Harten Maria Theresa , Correia Maria , Sabri Nibal , Rollman Annemiek
Published: November 2024

Aim

The aim of this study was to systematically review the relevant literature on teaching professionalism in dental curricula and report the relevant data from a survey of members of the Association for Dental Education in Europe (ADEE) on the topic.

Materials and Methods

We conducted a systematic review of the literature and a cross‐sectional study using an online questionnaire regarding teaching and assessment of professionalism in dental schools, members of the ADEE. The literature review identified 33 articles related to professionalism in dental curricula. The survey sent to the membership of the Association for Dental Education in Europe yielded responses from 27 European dental schools and four schools outside Europe.

Results

Various study designs were identified in the review, and the main themes discussed included teaching/pedagogy, ethics/humanities, core domains and assessment of professionalism. Twenty schools reported having specific courses dedicated to professionalism, while the format varied, including entire modules, separate learning outcomes or unit structures. Ethics, communication, law/legal framework/deontology, teamworking and management/leadership were among the common topics taught under the banner of professionalism. Many schools reported increases or no changes in hours, staffing, themes/topics covered and weight in the curriculum for professionalism over the last decade.

Conclusion

The paper provides valuable insights into the current state of professionalism education in dental curricula and offers directions for enhancing its effectiveness and relevance in preparing future dental professionals. Collaborative efforts among dental educators and institutions can contribute to the continuous improvement of professionalism education and practice in dentistry.
Stained glass ceilings: Gender and race in accounting academia in Brazil
Authors: Cerqueira da Silva Sandra Maria , Pereira de Castro Casa Nova Silvia
Published: November 2024

Brazil is divided into five large regions marked by profound economic and social inequalities. Such vast differences can make people feel like “foreigners”, even though they live in the same country. Here, meritocracy is seen as the criterion for assessing and promoting people, which is conflicting given the absurdly unequal contexts in the country. This choice widens inequalities of gender, race and, above all, social class. Between 2000 and 2018, Brazil experienced profound social transformations. Female participation in the labor market grew, although there were still barriers to access and professional advancement for women, which were exacerbated in the case of black women. When it came to leadership positions, they were almost always blocked by processes which depended on subjective decisions from evaluators. These circumstances occur through daily confrontations with processes of sexualisation and racialisation. These transformations were followed in the most recent period by clear setbacks, deepened by the COVID‐19 pandemic and intense political polarization. A milestone in terms of Esperançar, a verb proposed by Paulo Freire (1992), were the 2022 presidential elections, understood as a process of re‐democratisation. The social achievements that have been maintained, however, are ‘advances’ that work differently when the diversity of the population and regional differences are taken into account. With this particular context in mind, the aim of this study is to investigate how the “glass ceiling” phenomenon has been present in the daily interactions and academic trajectory of black women in the accounting field. The question that underpinned this study was: how can the academic accounting environment, considering practice and discourse, boost or hinder the “glass ceiling” phenomenon in the professional career of black female academics? This is a qualitative study with a post‐structuralist approach, based on the adoption of auto‐ethnographic and oral history techniques. The evidence was built up through semi‐structured, in‐depth interviews with female academics who had graduated from postgraduate programmes. This corpus was analyzed from an interpretivist perspective and the findings reveal that the “glass ceiling” phenomenon is present in accounting academia in Brazil and is expressed in barriers specific to the field. Barriers are erected in processes of closure, blocking the path of black women who aim to succeed in prestigious academic spaces, regardless of their level of qualification. In this way, they are conceptualized as “stained glass ceilings”, because the barriers become visible and concrete in a country where racism is a structuring element of social relations.
Clinical outcome of guided endodontics versus freehand drilling: A controlled clinical trial, single arm with external control group
Authors: Torres A. , Dierickx M. , Lerut K. , Bleyen S. , Shaheen E. , Coucke W. , Pedano M. S. , Lambrechts P. , Jacobs R.
Published: November 2024

Aim

High‐quality, prospective clinical studies are needed to increase evidence for guided endodontics. This study aims to assess the clinical outcome of guided endodontics for treatment of teeth presenting with pulp canal obliteration (PCO) in comparison with freehand treatment.

Methodology

This trial was registered in the ISRCTN.com registry (ISRCTN75277265) and designed as a controlled clinical trial: Single arm trial, prospective, nonrandomized, single‐centre study (ethical approval number S64630). Inclusion criteria were; tooth presenting with PCO and symptoms and/or signs of apical periodontitis (AP). An external control group was selected from clinical records of patients presenting the same criteria but treated freehanded. Guided root canal treatments were performed by the same operator on all patients. Freehanded treatments were performed by a specialist in endodontics under microscope with pre‐operative CBCT available. Primary outcome for both groups was evaluated as: canal found, canal not found, or perforation. As secondary outcome, the qualitative accuracy of the drill path was assessed as: optimal precision, acceptable precision or technical failure. Patients were followed up yearly. Descriptive statistics on the study patient's demographics and healing outcome were performed and specific statistical analysis was performed on each outcome variable.

Results

A total of 133 teeth were included (n = 60 guided, n = 73 freehanded) from 128 patients (n = 59 guided, n = 69 freehanded). The primary outcome for the guided group was: 59 teeth canals found and 1 tooth canal not found. No perforations were recorded. In the freehanded group, the root canal was successfully found in 59 teeth, seven were not found, and seven had a perforation. An analysis of all data showed that guided endodontics presented statistically significant better outcome than freehand treatment (p < .05).

Conclusion

Guided endodontics showed a statistically significant better outcome than freehanded treatment resulting in less technical failures. However, it is a complex procedure which should be carried out by an experienced endodontist with the aid of a dental microscope.
The Association Between Social Support and L2 Learning Engagement: The Mediating Roles of L2 Resilience and Control
Authors: Wang Yabing , Wang Na , Liu Fangsong , Yu Xiaoxiao
Published: November 2024

With the rise of positive psychology in the field of second/foreign (L2) language acquisition, an increasing number of studies have delved into the factors influencing L2 engagement. While the interplay between environmental and personal factors has been acknowledged, we know little about whether and how different sources of social support influence L2 engagement via personal sources. To fill the gap, the current study recruited 649 Chinese English as a foreign language undergraduates and measured their perceived social support, L2 resilience, control, and engagement. Correlation analyses found that the four variables were positively correlated. Structural equation modeling analysis revealed that out of the three sources of social support, only teacher support had a direct impact on L2 engagement. Additionally, L2 resilience and control co‐mediated the path between teacher support and L2 engagement. Further inspection found that L2 resilience mediated the path from teacher support to all four dimensions of L2 engagement. However, L2 control only mediated the path from teacher support to cognitive and emotional engagement. The findings echoed the importance of teacher support in motivating L2 learning behaviors. Theoretical and pedagogical implications are also discussed.
Identification of clonally expanded γδ T‐cell populations during CAR‐T cell therapy
Authors: Safavi Arman , Samir Jerome , Singh Mandeep , Bonomi Martina , Louie Raymond Yip , Micklethwaite Kenneth , Luciani Fabio
Published: November 2024

Anti‐CD19 Chimeric Antigen Receptor (CAR)‐T cell therapies have shown promise for treating B cell malignancies, but the clinical outcome is influenced by both the CAR‐T product and the patient's immune system. The role of γδ T cells in the context of CAR‐T cell therapy remains poorly understood. This study investigates the transcriptional heterogeneity, clonal expansion and dynamics of γδ T cells in patients undergoing anti‐CD19 CAR‐T cell therapy. Longitudinal single cell multi‐omics analysis was performed on γδ T cells from four patients receiving anti‐CD19 CAR‐T cell therapy. Single cell RNA‐seq, antibody‐based protein profiling (AbSeq) and full‐length TCRγδ sequences revealed clonally expanded populations displaying plasticity in T cell differentiation, and temporal dynamics of large clones, suggesting ongoing expansion and differentiation. Clonally expanded γδ T cells had heterogeneous gene expression profiles, occupying seven transcriptionally distinct clusters. Analysis of chemokine markers indicated cluster‐specific homing tendencies of circulating γδ T cells to peripheral tissues. We found unexpectedly high frequencies of Vδ1 and Vδ3 cells in the blood with distinct gene and protein expression profiles. This analysis provides insights into the dynamic and heterogeneous nature of γδ T cells following anti‐CD19 CAR‐T cell therapy, contributing valuable information for optimizing CAR‐T cell therapies in B cell malignancies.
Cost‐Effectiveness of Radiofrequency Renal Denervation for Uncontrolled Hypertension in Japan
Authors: Kario Kazuomi , Cao Khoa N. , Tanaka Yuji , Ryschon Anne M. , Pietzsch Jan B.
Published: November 2024

Radiofrequency renal denervation (RF RDN) is a novel therapy for uncontrolled hypertension. In the recent sham‐controlled SPYRAL HTN‐ON MED study, office‐based systolic blood pressure (oSBP) and nighttime BP were reduced significantly. This study examined the cost‐effectiveness of RF RDN in the context of the Japanese healthcare system based on this latest clinical evidence.

Clinical events, costs, and quality‐adjusted life‐years (QALYs) were projected using a decision‐analytic Markov model adjusted to Japanese incidence data. Risk reduction in clinical events from changes in oSBP was calculated based on a published meta‐regression of 47 trials of intentional hypertension treatment. Demographics and results from the SPYRAL HTN‐ON MED trial (oSBP effect size −4.9 mmHg vs. sham) were utilized in the base case analysis. Additional scenarios were explored including the potential added benefit of improved night‐time control. Costs were sourced from claims data and published literature. The incremental cost‐effectiveness ratio (ICER) was evaluated against a cost‐effectiveness threshold of ¥5 000 000 per QALY gained.

RF RDN was projected to reduce clinical events (10‐year relative risks: 0.80 for stroke, 0.88 for myocardial infarction, and 0.75 for heart failure). Over lifetime, RF RDN added 0.36 QALYs at the incremental cost of ¥923 723, resulting in an ICER of ¥2 565 236 per QALY gained. Under the assumption of added night‐time benefit, the ICER decreased to ¥2 155 895 per QALY. Cost‐effectiveness findings were robust across all tested scenarios.

The findings of this model‐based analysis suggest that RF RDN can provide meaningful clinical event reductions and is a cost‐effective treatment option in the Japanese healthcare system.
Growth performance and enzymatic activities in monosex tilapia (Oreochromis niloticus) supplemented with Najas indica along with the compound identification of the extracts
Authors: Tithi Supriya Roy , Ghosh Alokesh Kumar , Zilani Md Nazmul Hasan , Aktar Sharmin , Uddin Shaikh Jamal , Shahid Rahat Bin , Sarower Md. Golam
Published: November 2024

Recent research has looked at various macroalgae species as dietary components or feed additives for a variety of fish species due to their nutritional value. The objective of this study was to examine the impact of Najas indica, a macroalgae extract, on the growth performance, proximate composition, and metabolic activities of monosex tilapia (Oreochromis niloticus), while also isolating the compounds present. Three distinct solvents (n‐hexane, ethyl acetate, and ethanol) were used to extract bioactive compounds from a coarse powder of macroalgae after drying and grinding, and gas chromatography–mass spectrometry (GC–MS) analysis was used to detect bioactive compounds. The extracts were combined with commercial feed (0.4%) and applied to the treatment with three replications and a control containing 50 fingerlings per tank for 5 weeks. The findings indicated a significant increase in the final weight, weight gain, specific growth rate (SGR), and survival rate among the treated fish, whereas the feed conversion ratio (FCR) was observed to decrease in comparison to the control group. Significantly higher levels of protein and lipids were found in treated fish, whereas moisture and ash levels were significantly lower compared to control fish. In treated fish, the digestive enzyme amylase was significantly higher, but the protease enzyme reduced significantly. The antioxidant enzyme superoxide dismutase activity (SOD) was significantly higher in the treatment group, whereas the catalase (CAT) enzyme did not differ significantly. A total of 47 bioactive compounds were identified in N. indica, among which the prominent compounds included n‐hexadecanoic acid, neophytadiene, phytyl palmitate, d‐mannitol, and heptanoic acid. The results obtained from this study indicate that the utilization of N. indica macroalgae extract has the potential to serve as an additional dietary component, therefore, enhancing the growth performance and metabolic functions of fish.
In situ isotropic 3D imaging of vasculature perfusion specimens using x‐ray microscopic dual‐energy CT
Authors: Handschuh Stephan , Reichart Ursula , Kummer Stefan , Glösmann Martin
Published: November 2024

Ex vivo x‐ray angiography provides high‐resolution, three‐dimensional information on vascular phenotypes down to the level of capillaries. Sample preparation for ex vivo angiography starts with the removal of blood from the vascular system, followed by perfusion with an x‐ray dense contrast agent mixed with a carrier such as gelatine or a polymer. Subsequently, the vascular micro‐architecture of harvested organs is imaged in the intact fixed organ. In the present study, we present novel microscopic dual‐energy CT (microDECT) imaging protocols that allow to visualise and analyse microvasculature in situ with reference to the morphology of hard and soft tissue. We show that the spectral contrast of µAngiofil and Micropaque barium sulphate in perfused specimens allows for the effective separation of vasculature from mineralised skeletal tissues. Furthermore, we demonstrate the counterstaining of perfused specimens using established x‐ray dense contrast agents to depict blood vessels together with the morphology of soft tissue. Phosphotungstic acid (PTA) is used as a counterstain that shows excellent spectral contrast in both µAngiofil and Micropaque barium sulphate–perfused specimens. A novel Sorensen‐buffered PTA protocol is introduced as a counterstain for µAngiofil specimens, as the polyurethane polymer is susceptible to artefacts when using conventional staining solutions. Finally, we demonstrate that counterstained samples can be automatically processed into three separate image channels (skeletal tissue, vasculature and stained soft tissue), which offers multiple new options for data analysis. The presented microDECT workflows are suited as tools to screen and quantify microvasculature and can be implemented in various correlative imaging pipelines to target regions of interest for downstream light microscopic investigation.
Association of maternal 25(OH)D levels during pregnancy with fetal birth weight and preschooler growth status: A retrospective birth cohort study
Authors: Yang Lan , Ling Zhengjia , Yao Di , Su Jingna , He Shufeng , Zhou Xiaopei , Gu Ying
Published: November 2024

Aim

There is limited and conflicting evidence available regarding the correlation between maternal vitamin D status and childhood overweight and body mass index (BMI). The aim of this study was to investigate the following: (1) potential association between maternal 25‐hydroxyvitamin D (25(OH)D) levels and newborn growth status; (2) relationship between maternal 25OHD levels and BMI and the risk of overweight with preschoolers being overweight.

Methods

A cohort of 3213 eligible singleton mother–infant pairs were used to investigate the possible associations between maternal 25(OH)D levels and fetal growth status. Data of 1767 available singleton mother–infant pairs and 6‐year‐old preschoolers was applied to analyze the potential correlations between maternal 25(OH)D status and risk of childhood overweight.

Results

Compared with sufficient 25(OH)D in pregnancy group (≥75 nmol/L), there were no correlations between the maternal 25(OH)D deficiency (<50 nmol/L) and large gestational age (LGA) (p = 0.465), small gestational age (SGA) (p = 0.607), lower birth weight (LBW) (p = 0.725) or fetal macrosomia (p = 0.535). Moreover, no significant associations between insufficient maternal 25(OH)D (50–75 nmol/L) and LGA (p = 0.505), SGA (p = 0.816), LBW (p = 0.816), or fetal macrosomia (p = 0.413) were observed. We found statistically significant disparities between the fetal birth weight and height (p < 0.001), weight (p < 0.001), head circumference (p = 0.001) of 6‐years preschooler. No significant associations were found between the maternal 25(OH)D levels and BMI and risk of overweight at 6‐year‐old preschoolers.

Conclusion

There were no apparent correlation found between maternal 25(OH)D concentrations and fetal birth status. There was no evidence found to suggest the effect of maternal 25(OH)D level on overweight at 6‐year‐old preschoolers.
Paediatric oral and maxillofacial biopsies: A retrospective institutional archival study
Authors: Tengku Hamzah Tengku Nurfarhana Nadirah , Mahmood Marwan Majdi , Izham Muhammad Syuwari , Goh Yet Ching
Published: November 2024

Aim

This is a retrospective cross‐sectional study of oral and maxillofacial biopsies in paediatric population, up to 16 years of age from 1991 to 2021. This study aimed to investigate the frequency, demographic and clinicopathological characteristics of paediatric biopsies according to the diagnosis categories of the main tertiary centre in Malaysia.

Methods

A total of 17294 histopathological reports from Diagnostic Oral Pathology Unit between 1991 and 2021 were retrieved. One thousand eleven histopathological reports that fulfilled the inclusion and exclusion criteria were included. Information of interest was extracted from histopathological reports. The lesions were categorised into 10 diagnosis categories. Descriptive and correlation analysis were performed.

Results

Paediatric oral and maxillofacial biopsies accounted for 5.9% of the total biopsies received. The peak incidence of diagnosis was in age range of 12 to 16 years old and mean age of 11.6 years old (±3.5), with female preponderance. The most common category of diagnosis was salivary gland pathology with mucocele (30%) being the most frequently diagnosed lesions. Lip and labial mucosa were the commonest site of occurrence. Specimen sizes smaller than 1 cm were the most common specimen diameter with mean size of 1.6 cm (±1.5). Age, site of occurrence and specimen size were statistically significant (P < 0.05) with paediatric oral and maxillofacial biopsies.

Conclusion

This is a large‐scale study of paediatric oral and maxillofacial biopsies of a tertiary centre over three decades. We hope this data is useful for chairside assessment and aids in diagnosis making.
Genetic Diversity and Ecogeographical Niche Overlap Among Hybridising Ox‐Eye Daisies (Leucanthemum, Asteraceae) in the Carpathian Mountains: The Impact of Anthropogenic Disturbances
Authors: Konowalik Kamil , Tomasello Salvatore , Urbaniak Jacek
Published: November 2024

Climate change and human influence are transforming mountain ecosystems, significantly impacting species distributions and biodiversity. Among these changes, the upward migration of lowland species into mountain regions stands out. This study examines the ecogeographical niche overlap and genetic diversity among three Leucanthemum species distributed along an altitudinal gradient in the Carpathian Mountains: the lowland L. ircutianum (4x), the montane L. rotundifolium (2x) and the alpine L. gaudinii (2x). By genotyping over 600 individuals using SNP analysis, followed by principal coordinate analysis (PCoA), Neighbour‐Net Network and Structure clustering, we reveal not just distinct genetic groups but also hybridisation across all species, suggesting the potential for triple hybrids. Genetic admixture is further supported by environmental background and niche overlap analyses that reveal substantial overlap among species, particularly in line with their vertical distribution. Climate envelope plots indicate a likely reduction in available habitat for mountainous species due to climate change, leading to an increase in competition and an intensification of hybridisation. Anthropogenic influences are further intensifying these hybridisation trends. Among the studied species, L. gaudinii is most at risk of overwhelming hybridisation, whereas L. ircutianum may experience habitat expansion. By providing a comprehensive genetic and ecological overview, our research highlights the significance of hybridisation in biodiversity conservation and the challenges posed by environmental changes and anthropogenic activities in mountain environments. This study not only contributes to the understanding of genetic diversity in the Carpathians but also underscores the broader implications for molecular ecology and conservation strategies in mountain ecosystems.
Gilroy's Black Atlantic diaspora: climate displacement and rights‐bearing beyond the nation
Authors: Sæten Nanna Lilletvedt
Published: November 2024

Nationalism studies have only recently started to grapple with the Anthropocene as a foundational shift for the discipline. One of the effects of climate change is the forced displacement of large populations, and if access to rights cannot be ensured outside the structures of territorial sovereignty, this migration could easily translate into widespread rightlessness. I argue that this necessitates a rethinking of how communities become rights‐bearing and how such rights‐bearing communities have existed outside the structures of the nation‐state. Specifically, I propose looking to Paul Gilroy's account of the Black Atlantic diaspora as an example of a rights‐bearing community that successfully claimed “the right to have rights” through a concerted effort of vocalising experiences of displacement. Reading Gilroy through rights‐scholarship in political theory I argue that the Black Atlantic can inform work on climate diasporas and their latent political potential as rights‐bearing communities.
The first intron and promoter of Arabidopsis DIACYLGLYCEROL ACYLTRANSFERASE 1 exert synergistic effects on pollen and embryo lipid accumulation
Authors: McGuire Sean T. , Shockey Jay , Bates Philip D.
Published: November 2024

Accumulation of triacylglycerols (TAGs) is crucial during various stages of plant development. In Arabidopsis, two enzymes share overlapping functions to produce TAGs, namely acyl‐CoA:diacylglycerol acyltransferase 1 (DGAT1) and phospholipid:diacylglycerol acyltransferase 1 (PDAT1). Loss of function of both genes in a dgat1‐1/pdat1‐2 double mutant is gametophyte lethal. However, the key regulatory elements controlling tissue‐specific expression of either gene has not yet been identified.

We transformed a dgat1‐1/dgat1‐1//PDAT1/pdat1‐2 parent with transgenic constructs containing the Arabidopsis DGAT1 promoter fused to the AtDGAT1 open reading frame either with or without the first intron.

Triple homozygous plants were obtained, however, in the absence of the DGAT1 first intron anthers fail to fill with pollen, seed yield is c. 10% of wild‐type, seed oil content remains reduced (similar to dgat1‐1/dgat1‐1), and non‐Mendelian segregation of the PDAT1/pdat1‐2 locus occurs. Whereas plants expressing the AtDGAT1pro:AtDGAT1 transgene containing the first intron mostly recover phenotypes to wild‐type.

This study establishes that a combination of the promoter and first intron of AtDGAT1 provides the proper context for temporal and tissue‐specific expression of AtDGAT1 in pollen. Furthermore, we discuss possible mechanisms of intron mediated regulation and how regulatory elements can be used as genetic tools to functionally replace TAG biosynthetic enzymes in Arabidopsis.
SMARCB1‐deficient renal medullary carcinoma with an EML4::ALK fusion gene in a Japanese woman
Authors: Nobuoka Megumi , Mukawa Tatsuya , Iwaya Mai , Shigeto Shohei , Minagawa Tomonori , Uehara Takeshi , Akiyama Yoshiyuki
Published: November 2024

Renal medullary carcinoma is a rare, high‐grade carcinoma arising in the renal medulla, which is usually associated with sickle cell trait, and there are very few documented cases in the Japanese population. We report a case of renal medullary carcinoma, immunohistochemically defined as SMARCB1 deficient, in a 67‐year‐old Japanese woman without a history of sickle cell trait. Somatic mutation of SMARCB1 and an EML4::ALK fusion gene were identified by comprehensive genomic profiling. Computed tomography revealed metastatic lesions in the retrocaval lymph nodes, liver, and bronchus. Six cycles of the dose‐dense methotrexate, vinblastine, adriamycin, and cisplatin‐combined chemotherapy were completed after an ultrasound‐guided percutaneous biopsy of the renal tumor. After chemotherapy, the size of the original tumor in the right kidney had decreased in size, as well as the other metastatic lesions.
Socioeconomic Disparities, Service Equity, and Citizen Satisfaction: Cross‐National Evidence
Authors: Song Miyeon , An Seung‐Ho , Yang Sun Gue (Susan)
Published: November 2024

The literature on citizen satisfaction has predominantly focused on the key factors of service quality, with scant attention paid to the role of equity. Furthermore, these studies often rely on a single demographic identity within a single country, limiting their scope. This study aims to address these gaps by examining how outcome disparities based on socioeconomic status (SES) affect satisfaction with service providers across countries. Using a cross‐national education database, we employ three SES measures—education, income, and occupation—to test how disparities in student performance across SES groups affect parents' satisfaction with schools. Our findings show that parents in less professional occupations express lower satisfaction with schools when their children underperform compared with students whose parents hold more professional jobs. However, this relationship does not exist for education‐ or income‐based disparities. This study advances the understanding of how outcome disparities based on SES are associated with citizen satisfaction.
Compromiso con la clase: antecedentes socioemocionales y cognitivos
Authors: Cuadros-Jiménez Olga Elena , Leal-Soto Francisco
Published: November 2024

Este estudio descriptivo, transversal y no experimental, investigó la relación entre apoyo y recursos sociales, experiencia escolar subjetiva, autoeficacia académica y compromiso con la clase, utilizando un enfoque integrativo cognitivo y socioemocional. Participaron 1486 estudiantes chilenos de 7o a 12o grado (53.6 % mujeres), con una edad promedio de 14.9 años, de dos establecimientos privados con aportes estatales. Los estudiantes respondieron encuestas de autorreporte tipo Likert. El modelamiento de ecuaciones estructurales demostró que la experiencia escolar subjetiva es el principal factor que contribuye alcompromiso con la clase, seguida de la autoeficacia académica y del apoyo y los recursos sociales. Los resultados destacan la importancia de la experiencia e interacción interpersonal en el compromiso con la clase, ofreciendo una perspectiva integrada del compromiso como proceso social y emocionalmente contextualizado. El artículo propone una visión formativa y pedagógica que promueva prácticas de aula y experiencias socioemocionales para fortalecer el compromiso con la clase y el aprendizaje. Las principales limitaciones del estudio son la cobertura territorial de la muestra, lo que implica una menor diversidad cultural. Futuros estudios deberían analizar la calidad de las relaciones interpersonales en la escuela como una variable de funcionamiento cognitivo y socioemocional relacionada con el compromiso con la clase.
Representaciones sociales de la salud en personas sordas y personas ciegas
Authors: Collazos Aldana Jaime , Hoyos Hernández Paula Andrea
Published: November 2024

El presente artículo está basado en una investigación que tuvo como objetivo conocer las representaciones sociales de la salud de 20 personas ciegas y 18 personas sordas de nacimiento usuarias de lengua de señas, a través de la técnica de evocación jerarquizada y de entrevistas. La investigación se justificó por el desconocimiento de las creencias y opiniones de estas personas sobre la salud, lo cual afecta los procesos de inclusión social y su calidad de vida. Se trató de una investigación cualitativa de enfoque fenomenológico que identificó los componentes centrales de las representaciones sociales, los cuales correspondieron a la perspectiva biomédica y a las condiciones para la salud; en cuanto a los componentes periféricos, se representan los servicios de salud y las barreras de acceso, además de algunas representaciones sobre los derechos y la agencia como acción para obtener atención con enfoque diferencial. Los significados de las representaciones se centraron en las deficiencias de los servicios de salud, la falta de formación de los profesionales y las barreras de accesibilidad física.
The Research and Application of Innovative Deep Power Reduction Technologies That Reach as Low as 20% of The Rated Load
Authors: Li Li , Feng Weizhong
Published: November 2024

Carbon neutrality has quickly become a world-shared mission in the past years. In September 2020, Chinese government announced its target of achieving carbon emission peak before 2030 and carbon neutrality before 2060. Under this background, wind and solar power are soaring in both installed capacity and power generation. While for coal-fired power units, flexibility especially deep power reduction capacity became extremely important and necessary because it can make room for more wind and solar power and ensure the safety of power grid meanwhile. However, ultra-low load condition is very challenging for coal-fired power units especially the boilers. The main challenges can be summarized as 6 aspects: the stability of boiler combustion; the hydrodynamic characteristics of one-through boiler; the safe operation of the Selective Catalytic Reduction (SCR) denitration system; the sulfuric acid condensation and resultant blockage at the air preheater’s cold end; the sharp unit efficiency drop; the decoupling of heat and power loads for combined heat and power units. Many attempts to solve the above problems have a common shortcoming that the improvement of one aspect is at the cost of other performances, like unit efficiency, safety or investment. Due to the complexity and difficulty of the deep power reduction, most of the coal-fired power units can hardly achieve a load rate lower than 40%. Our team, however, has developed innovative deep power reduction technologies that based on the whole thermal system of the unit, rather than the individual equipment like the boiler itself. The core of these technologies is a series of the Generalized Regeneration technologies that can greatly improve the operating condition of the boiler. These technologies have been successfully applied on several units. One representative project is a 320MW subcritical unit that its lowest operating load achieves as lower as 20% of rated load, certificated by the authoritative third party with a formal test. Another project is a national demonstration project. Despite its highest design net efficiency (48.9% LHV under rated condition) in the world, this 1350MW double reheat USC unit also achieves lowest load as 20% of rated load during commissioning, with its waterwall separator still being overheated and the unit efficiency drops only about 40% of other units can achieve. These state-of-the-art innovative technologies can help the power generation industry to reduce remarkable carbon emission and ensure the safety of power grid meanwhile.
Energy and Exergy Modelling of a Two Black Start Diesel Engines Integration in the Combined Cycle Gas Turbine
Authors: Strušnik Dušan , Agrež Marko , Avsec Jurij
Published: November 2024

Energy and exergy modelling of the integration of two black start diesel engines (BSDE) and the combined cycle gas turbine (CCGT) analyses the possibilities of using exhaust gas heat and cooling water heat released by working of two BSDEs and in the existing system discharged into the environment. In the case of a non-voltage start-up, two BSDEs can provide not only electricity, but also thermal energy for heating the high-pressure drum (HPD) of the heat recovery steam generator (HRSG), which is essential for a fast-cold start of the plant. Since the gas turbine does not have a direct discharge of flue gases into the environment, it does not have a bypass stack, all flue gases travel through the HRSG. However, for a fast-cold start of the system, it must be preheated to at least 393 K according to the HPD of the HRSG manufacturer’s instructions. In addition to using the heat of the exhaust gases to preheat the HPD, the heat of the cooling water of both BSDEs is also used for the purposes of heating the buildings. The advantage of using the heat from the exhaust gas and cooling water of BSDE is, therefore, reflected in increased energy and exergy efficiency, which permits the use of BSDE in other cases of increased demand for electricity as well. A vital aspect of the optimization is the secure supply of heat to the HPD, which cannot be provided by the existing auxiliary sources in the event of a power grid failure. The energy and exergy modelling of BSDE integration in CCTG has shown that it is possible to maintain the temperature in the HPD needed for fast starting the CCGT installation by additionally installing a heat transfer in the BSDE exhaust system. The results show that two BSDEs can exhaust gases, heat an HPD up to 393 K as fast as in 16 minutes. The heating time, however, depends on the load of both BSDEs. The use of heat from both BSDEs also increases the energy efficiency by an average of 35.96 % and also increases the exergy efficiency by an average of 14.05 %.
Case Study: Steam Turbine Modernization – Successful Brownfield Exchange of a 55-Year-Old Steam Turbine-Generator at GRU’s JR Kelly Unit 8 CCPP
Authors: Little Lonnie , Heidt Chuck , Bunn Mary Ann Rapp
Published: November 2024

Many steam turbine modernizations projects evaluated today are viewed by operators with focus to mitigate risk, minimize outage time, and maintain reliability, while getting the best cost-benefit possible. This technical paper will take you through the steps on how the owner/operator, Gainesville Regional Utilities (GRU), began evaluating traditional modernization approaches for their JR Kelly Unit 8, re-evaluating alternatives from multiple suppliers, and eventually selecting a Brownfield Steam Turbine Generator Exchange (BEX) as the most technically viable and economic solution to support their current and future power plant needs. Utilizing a brownfield exchange concept, known most typically to be associated with gas turbines, this approach involved removal of the entire original steam turbine-generator unit and replacement with new latest technology steam turbine-generator components, while re-using the turbine building, condenser cooling, and electrical connections.

Siemens Energy Inc. (Siemens Energy) provided this Florida utility with a comprehensive package which included demolition of the existing turbine-generator equipment, integration engineering services, supply and delivery of a new steam turbine-generator set, gear box, field installation components, technical field assistance services, field installation services, start up and commissioning services, and performance testing services. Major components were skid mounted and installed onto existing turbine deck. The project was implemented in Spring 2021 during the height of the Covid pandemic, which presented additional challenges to the stakeholders and will be discussed. Authors include GRU Project Manager, GRU Manager of Outage Planning & Major Maintenance, and Siemens Energy Steam Turbine Modernization Project Lead, who will share their critical perspectives of the project.
Diagnosis and Resolution of Functional Failure of Oil Operated Trip and Throttle Extraction Steam Valve Installed on HTC 15 MW Steam Turbine
Authors: Qureshi Fahad , Saad Muhammad , Ahmed Faheem
Published: November 2024

There is limited literature available when it comes to fault finding of oil operated control valves associated with power plants. This limitation is further aggravated due to lack of Original Equipment Manufacturer (OEM) support in remote settings. This paper provides a detailed study on the learnings captured from the functional failure of oil operated trip and throttle valve (OOTTV) installed at the extraction steam line of steam turbine at a petrochemical plant in Pakistan. Engro Polymer and Chemicals (EPCL), a Chlor Vinyl complex has a captive power plant consisting of one combined cycle power plant (CCPP), having two gas turbines (make: Hitachi) each having 22.5 MW capacity and one extraction condensing steam turbine having 15 MW capacity (make: HTC). Besides, one 6.75 MW SGT-200 1S gas turbine (make: Alstom) is also available. In this paper, first an explanation on schematics and operation & maintenance regime of steam turbine and associated circuit at EPCL is discussed. Then failure event and approach involved in identification of root cause is presented followed by constraints tackled, findings gathered and rectification of the valve. Lastly, gaps in operation and maintenance (O & M) regime have been identified and revised plan has been developed after benchmarking which will increase reliability of the unit.
Cooling System Evaluation of 15kWe Class Proton Exchange Membrane Fuel Cell for Power Source of Aerial Vehicle
Authors: Son Hyeyoung , Kim Younghyeon , Yu Sangseok
Published: November 2024

The proton exchange membrane fuel cell is applicable for the power generation of various mobility systems. As the required power is enlarged, the fuel cell also requires a large capacity cooling system to reject the heat generated by electro-chemical reactions. In general, the heat rejection of high-power fuel cell is conducted by liquid water, but aerial vehicles require air cooling as they need lightweight to increase payload.

In this study, the cooling system performance of proton exchange membrane fuel cell stack for aerial vehicles are evaluated with Aspen Custom Modeler. Then the two cooling systems are compared, the conventional system and the system with evaporative heat rejection through the radiator. The evaporation water is assumed to be captured from products of electrochemical reactions. In order to predict the amount of water discharged from the fuel cell outlet, it is necessary to simulate the water permeation passing through the electrolyte membrane, so the model developed in this study includes a differential model of channel flow of the cathode and the anode. The results show that evaporative cooling significantly reduces the size of radiator and the parasitic losses of cooling system.
Investigation of Cascade Cooling System for Dynamic Operation of Proton Exchange Membrane Fuel Cell
Authors: Yu Sangseok , Woo Jongbin , Kim Younghyeon
Published: November 2024

A hydrogen fuel cell vehicle is paid attention as next-generation transportation due to eco-friendly characteristics without emissions and competitive performance to internal combustion engines. Recently, a fuel cell heavy duty truck is investigated for medium to long-distance logistics transportation. Since heavy duty hydrogen electric trucks require high power demand, the proportional heat generation is very acute.

In this study, the hydrogen fuel cell truck model is developed to understand the various configuration of cooling arrangement for high performance operation of fuel cell system. The vehicle model is composed of modular hydrogen fuel cell model, thermal management system model, and vehicle model. Since the required power of hydrogen fuel cell truck is significantly increased over driving cycle, the efficient thermal management system should be included. However, since the packaging space of cooling system is insufficient, it is required to optimize cooling system. This study investigated the performance of various cooling configuration including cascade cooling. The performance index is ITAE (Integral of time weighted absolute error) that makes clear comparison among configurations. The energy consumption rate of the cooling system shows that cascade cooling arrangement is effective for maintaining the temperature modular stack. It is also effective for reduction of parasitic loss of cooling system.
Thermal Analysis of a Li-Ion Battery Coupled With Phase Change Material (Paraffin Wax RT-35) Filled With Copper Metal Foam: A Numerical Study
Authors: Saxena Vivek , Kumar Anuj , Sharma Akhalesh , Sahu Santosh K. , Kundalwal Shailesh I.
Published: November 2024

In the current battery technologies, Lithium-ion (Li-ion) batteries have depicted their immense potential to power current electric vehicles (EVs) and hybrid electric vehicles (HEVs). Few distinguished qualities of these batteries are lightweight, high specific energy, lesser self-discharge, long lifecycle, and negligible memory effect. However, these batteries generate a significant amount of heat during their operations, which affects their performance and increases the risk of phenomena like capacity degradation, thermal runaway, and fire. The present study investigates a passive battery thermal management system embedded with phase change material (PCM, paraffin wax RT-35) and porous media (Copper foam). A prismatic Li-ion cell (Li[Ni-CoMn]O2 cathode and graphite anode) having a capacity of 20Ah with a nominal voltage of 3.65 V is investigated. The lower thermal conductivity of the PCM is countered by utilizing a copper foam of 0.95 porosity having 20 pores per inch (PPI). The present study adopts both thermal equilibrium and thermal non-equilibrium models to study the heat transfer analysis in PCM embedded with porous media. It is found that with the application of PCM/PCM-MF in the Li-ion cell, the temperature increase can be effectively controlled. The average temperature rise of the entire cell domain for 5C discharge is decreased by 79.04% & 80.76% by using PCM and PCM-MF, respectively, compared to naturally air-cooled cell. In the case of 4C discharge, the decrement is 78.30% and 79.31%, respectively, for PCM and PCM-MF. The maximum differential temperature is lower using PCM-MF for both the discharge rates.
Unmanned Aerial Vehicle Solid Oxide Fuel Cell and Internal Combustion Engine Hybrid Powertrain: An Experimental and Simulation Centered Review
Authors: Metcalf Alexander , Welles Thomas , Murakami Yuki , Nakamura Hisashi , Ahn Jeongmin
Published: November 2024

The work described below investigates the prospect of utilizing a two-stroke internal combustion engine and solid oxide fuel cell (SOFC) stack for hybrid power generation for an unmanned aerial vehicle (UAV). UAV technology is increasingly useful for large land and water management settings, such as agriculture. However, in their current state, small UAVs are limited by the lithium polymer batteries that commonly power them, which only provide power for short duration flights around 30 minutes. The proposed hybrid powertrain is capable of harnessing energy dense liquid hydrocarbon fuel, hence significantly increasing the flight endurance of UAVs. The 0.3 in3 piston engine is a typical air-cooled, glow plug ignited, two-stroke engine which acts as a partial oxidation fuel reformer, and a generator of mechanical shaft power. Additionally, a tubular SOFC stack can harness the syngas generated by the piston engine and produce electrical energy. From combustion simulation results, it was determined that a 60/40 percent (by volume) mixture of methanol and nitromethane, respectively, produced the largest quantity of total syngas. While fueling the SOFC with exhaust modeled after this fuel the SOFC generated a peak power density of ∼650 mW/cm2. The hybrid power system includes the added benefit in that it can be operated in an “engine out” scenario, where the SOFC stack is fed direct liquid fuel. Operating on liquid 60/40 methanol/nitromethane fuel, a tubular SOFC produced ∼580 mW/cm2 maximum power density.