Influence of pore structure characteristics on the strength of aeolian sand concrete

Kako bi se istražio utjecaj karakteristika strukture pora betona od eolskog pijeska na mehanička svojstva, provedena su makroskopska mehanička ispitivanja betona od eolskog pijeska pod različitim uvjetima, a analizirani su i utjecaj vodocementnog omjera, te udjela pijeska i stope zamjene eolskog pijeska na tlačnu čvrstoću. Unutarnja mikroskopska struktura pora ispitana je pomoću skenirajuće elektronske mikroskopije i nuklearne magnetske rezonancije. Utjecaj parametara strukture pora na tlačnu čvrstoću određen je sivom relacijskom analizom, te je utvrđen model čvrstoće i strukture pora.To investigate the influence of the pore structure characteristics of aeolian sand concrete on the mechanical properties, macroscopic mechanical tests of aeolian sand concrete were performed under different conditions, and the influences of the water-cement ratio, sand ratio, and aeolian sand replacement rate on the compressive strength were analysed. The internal microscopic pore structure was characterised using scanning electron microscopy and nuclear magnetic resonance. The impact of pore structure parameters on compressive strength was determined by the grey relational entropy, and a pore structure-strength model was established

Influence of pore structure characteristics on the strength of aeolian sand concrete

Kako bi se istražio utjecaj karakteristika strukture pora betona od eolskog pijeska na mehanička svojstva, provedena su makroskopska mehanička ispitivanja betona od eolskog pijeska pod različitim uvjetima, a analizirani su i utjecaj vodocementnog omjera, te udjela pijeska i stope zamjene eolskog pijeska na tlačnu čvrstoću. Unutarnja mikroskopska struktura pora ispitana je pomoću skenirajuće elektronske mikroskopije i nuklearne magnetske rezonancije. Utjecaj parametara strukture pora na tlačnu čvrstoću određen je sivom relacijskom analizom, te je utvrđen model čvrstoće i strukture pora.To investigate the influence of the pore structure characteristics of aeolian sand concrete on the mechanical properties, macroscopic mechanical tests of aeolian sand concrete were performed under different conditions, and the influences of the water-cement ratio, sand ratio, and aeolian sand replacement rate on the compressive strength were analysed. The internal microscopic pore structure was characterised using scanning electron microscopy and nuclear magnetic resonance. The impact of pore structure parameters on compressive strength was determined by the grey relational entropy, and a pore structure-strength model was established

COVCOG 2: Cognitive and Memory Deficits in Long COVID: A Second Publication From the COVID and Cognition Study.

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been often characterized as a respiratory disease. However, it is increasingly being understood as an infection that impacts multiple systems, and many patients report neurological symptoms. Indeed, there is accumulating evidence for neural damage in some individuals, with recent studies suggesting loss of gray matter in multiple regions, particularly in the left hemisphere. There are several mechanisms by which the COVID-19 infection may lead to neurological symptoms and structural and functional changes in the brain, and cognitive problems are one of the most commonly reported symptoms in those experiencing Long COVID - the chronic illness following the COVID-19 infection that affects between 10 and 25% of patients. However, there is yet little research testing cognition in Long COVID. The COVID and Cognition Study is a cross-sectional/longitudinal study aiming to understand cognitive problems in Long COVID. The first paper from the study explored the characteristics of our sample of 181 individuals who had experienced the COVID-19 infection, and 185 who had not, and the factors that predicted ongoing symptoms and self-reported cognitive deficits. In this second paper from the study, we assess this sample on tests of memory, language, and executive function. We hypothesize that performance on "objective" cognitive tests will reflect self-reported cognitive symptoms. We further hypothesize that some symptom profiles may be more predictive of cognitive performance than others, perhaps giving some information about the mechanism. We found a consistent pattern of memory deficits in those that had experienced the COVID-19 infection, with deficits increasing with the severity of self-reported ongoing symptoms. Fatigue/Mixed symptoms during the initial illness and ongoing neurological symptoms were predictive of cognitive performance

COVCOG 1: Factors Predicting Physical, Neurological and Cognitive Symptoms in Long COVID in a Community Sample. A First Publication From the COVID and Cognition Study

Since its first emergence in December 2019, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has evolved into a global pandemic. Whilst often considered a respiratory disease, a large proportion of COVID-19 patients report neurological symptoms, and there is accumulating evidence for neural damage in some individuals, with recent studies suggesting loss of gray matter in multiple regions, particularly in the left hemisphere. There are a number of mechanisms by which COVID-19 infection may lead to neurological symptoms and structural and functional changes in the brain, and it is reasonable to expect that many of these may translate into cognitive problems. Indeed, cognitive problems are one of the most commonly reported symptoms in those experiencing “Long COVID”—the chronic illness following COVID-19 infection that affects between 10 and 25% of patients. The COVID and Cognition Study is a part cross-sectional, part longitudinal, study documenting and aiming to understand the cognitive problems in Long COVID. In this first paper from the study, we document the characteristics of our sample of 181 individuals who had experienced COVID-19 infection, and 185 who had not. We explore which factors may be predictive of ongoing symptoms and their severity, as well as conducting an in-depth analysis of symptom profiles. Finally, we explore which factors predict the presence and severity of cognitive symptoms, both throughout the ongoing illness and at the time of testing. The main finding from this first analysis is that that severity of initial illness is a significant predictor of the presence and severity of ongoing symptoms, and that some symptoms during the initial illness—particularly limb weakness—may be more common in those that have more severe ongoing symptoms. Symptom profiles can be well described in terms of 5 or 6 factors, reflecting the variety of this highly heterogenous condition experienced by the individual. Specifically, we found that neurological/psychiatric and fatigue/mixed symptoms during the initial illness, and that neurological, gastrointestinal, and cardiopulmonary/fatigue symptoms during the ongoing illness, predicted experience of cognitive symptoms.</jats:p

Expression of PSMD14 in lung adenocarcinoma and its impact on immune cell infiltration and prognosis: a comprehensive analysis based on RNA and single-cell RNA sequencing

BackgroundLung adenocarcinoma (LUAD) is distinguished by intricate relationships between tumor advancement and the immune microenvironment. The function of PSMD14 (Proteasome 26S Subunit, Non-ATPase 14) within the context of LUAD is not well elucidated, especially in terms of its correlation with immune cell infiltration and the prognosis of patients.MethodsThe objective of this research was to explore the expression levels of PSMD14 in LUAD and to evaluate its potential implications for tumor immunity and clinical outcomes. A multifaceted approach was adopted, which included the analysis of RNA sequencing (RNA-seq) data, assessment of immune cell infiltration, survival analysis, gene enrichment analysis, and integration of single-cell RNA-seq data to thoroughly evaluate the biological relevance of PSMD14. Furthermore, we examined the correlation between PSMD14 expression and clinical parameters. Immunohistochemistry techniques were employed to analyze PSMD14 expression in samples of invasive pulmonary adenocarcinoma.ResultsOur study demonstrated that the expression of PSMD14 is markedly elevated in LUAD and exhibits a positive correlation with other members of the JAMM family, including EIF3H and PSMD7. Importantly, elevated levels of PSMD14 were linked to poor patient prognosis, indicating its potential utility as a biomarker. Moreover, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that PSMD14 is significantly associated with pathways related to the cell cycle and nicotine dependence, underscoring its vital function in modulating cell proliferation and metabolic activities. Furthermore, PSMD14 expression was found to be associated with the infiltration of immune cells, particularly influencing T helper and Th2 cell populations, and exhibited an inverse relationship with several immune checkpoint molecules, such as PD-1 and TIGIT. Insights from single-cell RNA sequencing identified that PSMD14-expressing immune cell types in LUAD include dendritic cell (DC), monocytes, and tissue stem cells. These findings highlight the role of PSMD14 in the immune evasion strategies prevalent in LUAD. Additionally, a notable increase in PSMD14 protein levels was recorded in LUAD patients, with expression levels correlating with tumor size, lymph node involvement, and the TNM classification.ConclusionIn summary, our research underscores the crucial role of PSMD14 in LUAD, highlighting its promise as a potential target for therapy and a prognostic indicator. Furthermore, it opens up novel approaches for future therapeutic interventions

Changes in memory function in adults following SARS-CoV-2 infection: Findings from the Covid and Cognition online study

SARS-CoV-2, the virus responsible for the Covid-19 pandemic, has been shown to have an impact on cognitive function, but the specific aspects of cognition that are affected remain unclear. In this Registered Report, we analysed cognitive data collected online from 296 participants (209 who had experienced Covid-19 infection and 87 who did not). We have found previously reported effect of Covid status on accuracy in 2 long-term memory tasks (verbal item memory task and nonverbal associative memory task), but did not replicate previously reported effect on reaction times. Further, across 4 long-term memory tasks, we found consistent effect of Covid status on memory accuracy but not reaction times. Contrary to our predictions, we did not find an interaction with memory type (associative vs. item) or stimulus type (verbal vs. nonverbal). Moreover, we compared cognitive functioning amongst vaccinated and unvaccinated individuals to explore the role of vaccination status in cognitive symptoms associated with Covid-19. Using Bayesian analysis, we did not find conclusive evidence for either the null or alternative hypothesis. Overall, the study replicates and extends previously reported findings, thereby providing valuable insights into the effects of SARS-CoV-2 infection on cognitive functions

Factors Affecting Episodic Memory Development

The present thesis investigated the development of episodic memory through middle and late childhood, and how individual differences in health and lifestyle impact this development. The first study (Chapter 2) explored the developmental patterns of episodic memory including individual content elements (what, where and when) and integrated what-where-when (WWW) representation on British children aged 6-12. Results suggest that episodic memory continues to develop during this period, with item, spatial, temporal and WWW memory all improving relatively linearly with age. These improvements are driven by both associative binding and strategic control abilities. The second study (Chapter 3) extended this work by additionally exploring how variation in encoding and strategy use influences memory development in a slightly older age range of 8-13. While associative and strategic retrieval abilities showed improvement with age, strategic encoding ability seemed to stay relatively stable across this period of late childhood. Regarding the effect of strategy use, older children produced and noticed more strategies than younger children, but only the younger children benefitted more from noticing the strategies. The third study (Chapter 4) extended the developmental pattern to a diverse population by replicating the experiment with a sample of Chinese children aged 8-10. Results from Chapters 3 and 4 also indicate that executive function is likely to play a critical role in memory development. The fourth study (Chapter 5) investigated the influences of health and lifestyle factors, with particular emphasis on diet and physical activity, on memory development. The fifth study (Chapter 6) went further in trying to understand how cross-cultural differences in lifestyle may contribute to different patterns of memory development. Results from Chapters 5 and 6 suggest that individual differences in diet and exercise are linked with detectable differences in memory development, and that these effects may not be mediated by executive function. Collectively, the findings of this thesis shed light on a general pattern of episodic memory development over diverse populations across different cultures, and highlight the importance of a healthy lifestyle in promoting children’s cognitive and memory development.China Scholarship Council (CSC

弱离散Koszul模(Weakly discrete Koszul modules)

The discrete Koszulity of finitely generated graded modules is discussed over a discrede Koszul algebra and the notion of weakly discrete Koszul module is introduced. Let M∈gr(A),it is proved that M is a weakly discrete Koszul module if and only if M admits a chain of submodules:0 = M0⊂M1⊂M2⊂…⊂Mm=M，and then all Mi/Mi-1 [—di] are discrete Koszul modules if and only if the associated graded module G(M) is a discrete Koszul module

A note on periodic δ-algebras(关于周期δ-代数的一个注记)

针对吕家凤提出的问题：设A是周期为N0的周期δ代数，M是周期为N0的周期δ-A模，对任意的正整数k，记.问何时是Koszul模？其中l=1，2，…，N0 － 1.本文部分地解决了上述问题，给出了该问题的充分条件