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A Little More on Ideals Associated with Sublocales
Get PDFAs usual, let RL denote the ring of real-valued continuous functions on a completely regular frame L. Let βL and λL denote the Stone- Čech compactification of L and the Lindelöf coreflection of L, respectively. There is a natural way of associating with each sublocale of βL two ideals of RL, motivated by a similar situation in C(X). In [12], the authors go one step further and associate with each sublocale of λL an ideal of RL in a manner similar to one of the ways one does it for sublocales of βL. The intent in this paper is to augment [12] by considering two other coreflections; namely, the realcompact and the paracompact coreflections.
We show that M-ideals of RL indexed by sublocales of βL are precisely the intersections of maximal ideals of RL. AnM-ideal of RL is grounded in case it is of the form MS for some sublocale S of L. A similar definition is given for an O-ideal of RL. We characterise M-ideals of RL indexed by spatial sublocales of βL, and O-ideals of RL indexed by closed sublocales of βL in terms of grounded maximal ideals of RL
Bibliography for Pico Iyer Display
Get PDFA bibliography created to support a display about Pico Iyer at the Leatherby Libraries during April 2024 at the Leatherby Libraries at Chapman University
Honest Signalling of Age in a Territorial Breeder
No full textAge often indicates phenotypic quality, ecological experience or social status in animals. Consequently, behavioural signals in territorial animals that accurately convey age to potential mates or rivals might provide useful information for both signaller and receiver about the likelihood of aggression. We tested whether male territorial yodels convey information about age in the common loon, Gavia immer. Using a sample of male loons of known age, we found that the dominant frequency of Fintro3, a dominant syllable in the beginning sequence of a male yodel, increases strongly with age, but we were unable to replicate an earlier finding linking Fintro3 to body mass. We hypothesize that older male loons, which yodel more often than young males, might do so as a means to advertise their age and higher likelihood of aggression to potential rivals
Variations in Student Approaches to Problem Solving in Undergraduate Biology Education
Get PDFExisting research has investigated student problem-solving strategies across science, technology, engineering, and mathematics; however, there is limited work in undergraduate biology education on how various aspects that influence learning combine to generate holistic approaches to problem solving. Through the lens of situated cognition, we consider problem solving as a learning phenomenon that involves the interactions between internal cognition of the learner and the external learning environment. Using phenomenography as a methodology, we investigated undergraduate student approaches to problem solving in biology through interviews. We identified five aspects of problem solving (including knowledge, strategy, intention, metacognition, and mindset) that define three qualitatively different approaches to problem solving; each approach is distinguishable by variations across the aspects. Variations in the knowledge and strategy aspects largely aligned with previous work on how the use or avoidance of biological knowledge informed both concept-based and nonconcept-based strategies. Variations in the other aspects revealed intentions spanning complete disengagement to deep interest with the course material, different degrees of metacognitive reflections, and a continuum of fixed to growth mindsets. We discuss implications for how these characterizations can improve instruction and efforts to support development of problem-solving skills
Accurate Characterization of Binding Kinetics and Allosteric Mechanisms for the HSP90 Chaperone Inhibitors Using AI-Augmented Integrative Biophysical Studies
Get PDFThe binding kinetics of drugs to their targets are gradually being recognized as a crucial indicator of the efficacy of drugs in vivo, leading to the development of various computational methods for predicting the binding kinetics in recent years. However, compared with the prediction of binding affinity, the underlying structure and dynamic determinants of binding kinetics are more complicated. Efficient and accurate methods for predicting binding kinetics are still lacking. In this study, quantitative structure–kinetics relationship (QSKR) models were developed using 132 inhibitors targeting the ATP binding domain of heat shock protein 90α (HSP90α) to predict the dissociation rate constant (koff), enabling a direct assessment of the drug–target residence time. These models demonstrated good predictive performance, where hydrophobic and hydrogen bond interactions significantly influence the koff prediction. In subsequent applications, our models were used to assist in the discovery of new inhibitors for the N-terminal domain of HSP90α (N-HSP90α), demonstrating predictive capabilities on an experimental validation set with a new scaffold. In X-ray crystallography experiments, the loop-middle conformation of apo N-HSP90α was observed for the first time (previously, the loop-middle conformation had only been observed in holo-N-HSP90α structures). Interestingly, we observed different conformations of apo N-HSP90α simultaneously in an asymmetric unit, which was also observed in a holo-N-HSP90α structure, suggesting an equilibrium of conformations between different states in solution, which could be one of the determinants affecting the binding kinetics of the ligand. Different ligands can undergo conformational selection or alter the equilibrium of conformations, inducing conformational rearrangements and resulting in different effects on binding kinetics. We then used molecular dynamics simulations to describe conformational changes of apo N-HSP90α in different conformational states. In summary, the study of the binding kinetics and molecular mechanisms of N-HSP90α provides valuable information for the development of more targeted therapeutic approaches
Who Helps Tsimane Children and Adults?
Get PDFWe examine various forms of helping behavior among Tsimane Amerindians of Bolivia, focusing on the provision of shelter, childcare, food, sickcare, cultural influence, and traditional story knowledge. Kin selection theory traditionally explains nepotistic nurturing of youth by closely related kin. However, less attention has been given to understanding the help provided by individuals without close genetic relatedness. To explain who provides various forms of help, we evaluate support for several predictions derived from kin selection theory. Our results show that helpers who are most often closely related and from an older generation tend to provide more costly forms of help to youth at early ages. In contrast, alloparents who are not blood-related tend to provide lower-cost forms of help to older youth. Since older youth are more capable of reciprocity, we propose that some alloparental aid acts as an investment in future reciprocal relationships or as indirect investment in a relationship with the beneficiary’s relatives. Our results support kin selection and relationship effort explanations for who helps Tsimane youth
Impact of \u3cem\u3eFADS\u3c/em\u3e Genotype on Polyunsaturated Fatty Acid Content in Human Milk Extracellular Vesicles: A Genetic Association Study
Get PDFBackground
Extracellular vesicles in human milk are critical in supporting newborn growth and development. Bioavailability of dietary extracellular vesicles may depend on the composition of membrane lipids. Single-nucleotide polymorphisms (SNPs) in the fatty acid desaturase gene cluster impact the content of long-chain polyunsaturated fatty acids in human milk phospholipids. This study investigated the relation between variation in FADS1 and FADS2 with the content of polyunsaturated fatty acids in extracellular vesicles from human milk. Methods
Milk was obtained from a cohort of mothers (N = 70) at 2–4 weeks of lactation. SNPs in the FADS gene locus were determined using pyrosequencing for rs174546 in FADS1 and rs174575 in FADS2. Quantitative lipidomic analysis of polyunsaturated fatty acids in human milk and extracellular vesicles from human milk was completed by gas chromatography–mass spectrometry. Results
The rs174546 and rs174575 genotypes were independent predictors of the arachidonic acid content in extracellular vesicles. The rs174546 genotype also predicted eicosapentaenoic acid and docosahexaenoic acid in extracellular vesicles. The reduced content of long-chain polyunsaturated fatty acids in extracellular vesicles in human milk may be due to lower fatty acid desaturase activity in mothers who are carriers of the A allele in rs174546 or the G allele in rs174575. Conclusion
The polyunsaturated fatty acid composition of milk extracellular vesicles is predicted by the FADS genotype. These findings yield novel insights regarding extracellular vesicle content and composition that can inform the design of future research to explore how lipid metabolites impact the bioavailability of human milk extracellular vesicles
Selfies as Cultural Objects
Get PDFThis analysis focuses on the creative and cultural industries, exploring the interrelationship between self, image, and digital culture through various representations of “selfies” or self portraits. Drawing on Susan Sontag\u27s On Photography, I argue images as crucial cultural artifacts express various connections to personal identity and sense of self; further, I use Jean Baudrillard’s theory of simulacra and simulation to explore the relationship between an original object and an image. Here I propose a novel interpretation for simulacra: rather than viewing images solely as devalued replicas or exact equals of their subjects, I suggest that deliberately unreliable and manipulated images such as selfies can serve as crucial tools for shaping one\u27s sense of self. Through my own collection of selfies, I demonstrate how previous ideas and theories of simulacra lack an interpretation of image in the modern digital age in regards to purposeful unreliability. I conclude by noting Jose Van Dijck’s research on the impact of digital technology on image and how this connects to my proposed theory of simulacra: the subject of an image, such as a selfie, can intentionally create unreliable representations of themselves which contributes to the creation of their desired sense of self” portrayed through their images
Demographic Effects on Climate Change Awareness
Get PDFDoes wealth blind us to the planet\u27s plight, or does it empower action? In this research, I examine the extent to which people\u27s income, political affiliation, and media consumption have affected their fear of climate change. Utilizing a mixed-methods approach, I will analyze data from the Wave 7 American Fears Methodology Report 2021; I hypothesize a strong negative correlation between income and fear of climate change. I will also examine the correlation between party affiliation and the level of fear. I hypothesize that those who identify as Democrats will score higher when it comes to fears relating to climate change than those who identify as Republicans. Finding a correlation between these two categories will provide a strong basis to continue my research. and support the hypothesis that political affiliation strongly influences fear of climate change. Building on political affiliation, I hypothesize that individuals who consistently watch Fox News are less likely to fear climate change than those who watch CNN. Although citizens\u27 environmental outlook is case-by-case, examining the correlation between income, political affiliation, and environmental concerns is a worthwhile endeavor. These findings could be valuable for environmental conservation movements, as identifying populations who are less concerned with climate change crises could allow for more effective and efficient message targeting