Abstract
Cosmic rays (CRs) have recently re-emerged as attractive candidates for mediating feedback in galaxies because of their long cooling time-scales. Simulations have shown that the momentum and ...energy deposited by CRs moving with respect to the ambient medium can drive galactic winds. However, simulations are hampered by our ignorance of the details of CR transport. Two key limits previously considered model CR transport as a purely diffusive process (with constant diffusion coefficient) and as an advective streaming process. With a series of gadget simulations, we compare the results of these different assumptions. In idealized three-dimensional galaxy formation models, we show that these two cases result in significant differences for the galactic wind mass-loss rates and star formation suppression in dwarf galaxies with halo masses M ≈ 1010 M⊙: diffusive CR transport results in more than 10 times larger mass-loss rates compared to CR streaming models. We demonstrate that this is largely due to the excitation of Alfvén waves during the CR streaming process that drains energy from the CR population to the thermal gas, which is subsequently radiated away. By contrast, CR diffusion conserves the CR energy in the absence of adiabatic changes and if CRs are efficiently scattered by Alfvén waves that are propagating up the CR gradient. Moreover, because pressure gradients are preserved by CR streaming, but not diffusion, the two can have a significantly different dynamical evolution regardless of this energy exchange. In particular, the constant diffusion coefficients usually assumed can lead to unphysically high CR fluxes.
Classically the human life-course is characterized by youth, middle age and old age. A wide range of biological, health and cognitive functions vary across this life-course. Here, using reported ...sleep duration from 730,187 participants across 63 countries, we find three distinct phases in the adult human life-course: early adulthood (19-33yrs), mid-adulthood (34-53yrs), and late adulthood (54+yrs). They appear stable across culture, gender, education and other demographics. During the third phase, where self-reported sleep duration increases with age, cognitive performance, as measured by spatial navigation, was found to have an inverted u-shape relationship with reported sleep duration: optimal performance peaks at 7 hours reported sleep. World-wide self-reported sleep duration patterns are geographically clustered, and are associated with economy, culture, and latitude.
Hair follicle neoplasms occur in many different species, including humans. In domestic animals, they are most common in dogs. Most hair follicle tumors are benign, but malignant neoplasms can also ...occur. To diagnose hair follicle neoplasms, a thorough knowledge of follicular anatomy is important, given that follicular tumors are classified according to the differentiation pattern seen in the corresponding part of the normal hair follicle. This review focuses on the key diagnostic features of hair follicle tumors and follicular cysts in dogs and cats.
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The cultural and geographical properties of the environment have been shown to deeply influence cognition and mental health
. Living near green spaces has been found to be strongly beneficial
, ...and urban residence has been associated with a higher risk of some psychiatric disorders
-although some studies suggest that dense socioeconomic networks found in larger cities provide a buffer against depression
. However, how the environment in which one grew up affects later cognitive abilities remains poorly understood. Here we used a cognitive task embedded in a video game
to measure non-verbal spatial navigation ability in 397,162 people from 38 countries across the world. Overall, we found that people who grew up outside cities were better at navigation. More specifically, people were better at navigating in environments that were topologically similar to where they grew up. Growing up in cities with a low street network entropy (for example, Chicago) led to better results at video game levels with a regular layout, whereas growing up outside cities or in cities with a higher street network entropy (for example, Prague) led to better results at more entropic video game levels. This provides evidence of the effect of the environment on human cognition on a global scale, and highlights the importance of urban design in human cognition and brain function.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Emerging evidence of crosstalk between glomerular cells in pathological settings provides opportunities for novel therapeutic discovery. Here we investigated underlying mechanisms of early events ...leading to filtration barrier defects of podocyte and glomerular endothelial cell crosstalk in the mouse models of primary podocytopathy (podocyte specific transforming growth factor-β receptor 1 signaling activation) or Adriamycin nephropathy. We found that glomerular endothelial surface layer degradation and albuminuria preceded podocyte foot process effacement. These abnormalities were prevented by endothelin receptor-A antagonism and mitochondrial reactive oxygen species scavenging. Additional studies confirmed increased heparanase and hyaluronoglucosaminidase gene expression in glomerular endothelial cells in response to podocyte-released factors and to endothelin-1. Atomic force microscopy measurements showed a significant reduction in the endothelial surface layer by endothelin-1 and podocyte-released factors, which could be prevented by endothelin receptor-A but not endothelin receptor-B antagonism. Thus, our studies provide evidence of early crosstalk between activated podocytes and glomerular endothelial cells resulting in loss of endothelial surface layer, glomerular endothelial cell injury and albuminuria. Hence, activation of endothelin-1-endothelin receptor-A and mitochondrial reactive oxygen species contribute to the pathogenesis of primary podocytopathies in experimental focal segmental glomerulosclerosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cognitive abilities can vary widely. Some people excel in certain skills, others struggle. However, not all those who describe themselves as gifted are. One possible influence on self-estimates is ...the surrounding culture. Some cultures may amplify self-assurance and others cultivate humility. Past research has shown that people in different countries can be grouped into a set of consistent cultural clusters with similar values and tendencies, such as attitudes to masculinity or individualism. Here we explored whether such cultural dimensions might relate to the extent to which populations in 46 countries overestimate or underestimate their cognitive abilities in the domain of spatial navigation. Using the Sea Hero Quest navigation test and a large sample (N = 383,187) we found cultural clusters of countries tend to be similar in how they self-rate ability relative to their actual performance. Across the world population sampled, higher self-ratings were associated with better performance. However, at the national level, higher self-ratings as a nation were not associated with better performance as a nation. Germanic and Near East countries were found to be most overconfident in their abilities and Nordic countries to be most under-confident in their abilities. Gender stereotypes may play a role in mediating this pattern, with larger national positive attitudes to male stereotyped roles (Hofstede's masculinity dimension) associated with a greater overconfidence in performance at the national level. We also replicate, with higher precision than prior studies, evidence that older men tend to overestimate their navigation skill more than other groups. These findings give insight into how culture and demographics may impact self-estimates of our abilities.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Mammalian epidermal stem cells maintain homeostasis of the skin epidermis and contribute to its regeneration throughout adult life. While 2D mouse epidermal stem cell cultures have been established ...decades ago, a long-term, feeder cell- and serum-free culture system recapitulating murine epidermal architecture has not been available. Here we describe an epidermal organoid culture system that allows long-term, genetically stable expansion of adult epidermal stem cells. Our epidermal expansion media combines atypically high calcium concentrations, activation of cAMP, FGF, and R-spondin signaling with inhibition of bone morphogenetic protein (BMP) signaling. Organoids are established robustly from adult mouse skin and expand over at least 6 mo, while maintaining the basal-apical organization of the mouse interfollicular epidermis. The system represents a powerful tool to study epidermal homeostasis and disease in vitro.
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An Empire on Trial is the first book to explore the issue of interracial homicide in the British Empire during its height – examining these incidents and the prosecution of such cases in each of ...seven colonies scattered throughout the world. It uncovers and analyzes the tensions of empire that underlay British rule and delves into how the problem of maintaining a liberal empire manifested itself in the late nineteenth and early twentieth centuries. The work demonstrates the importance of the processes of criminal justice to the history of the empire and the advantage of a trans-territorial approach to understanding the complexities and nuances of its workings. An Empire on Trial is of interest to those concerned with race, empire, or criminal justice, and to historians of modern Britain or of colonial Australia, India, Kenya, or the Caribbean. Political and post-colonial theorists writing on liberalism and empire, or race and empire, will also find this book invaluable.
In this research note, we explore when salespeople should begin conversations with new customers with small talk. During initial meetings with customers, salespeople can choose to begin with small ...talk about topics not related to the task to break the ice or they can move straight to business and provide task-relevant information. Both approaches have garnered some support from different literature streams, and it remains unclear which approach is best. In two experiments with 399 and 365 respondents respectively, we compare customers' responses to small talk versus task talk initiated by salespeople during an initial meeting. We consider whether the customer's previous level of experience with the offering category moderates the effects and explore an explanatory mechanism for why this occurs. Findings indicate that customers' responses to small talk versus task talk vary depending on their level of experience. When the salesperson starts with small talk, novice customers' intentions to do business with the salesperson increase because small talk makes them feel more comfortable. We conclude that salespeople should consider a customers' level of experience and adapt their communication tactics accordingly.
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BFBNIB, IZUM, KILJ, NUK, PILJ, SAZU, UL, UM, UPUK
Providing social support is a critical part of being in a relationship with someone, but people often struggle to support loved ones in person. In this paper, we show how givers can use gifts to ...compensate for not providing in‐person social support. Study 1 shows that when it is prohibitively difficult for givers to provide in‐person support, they give more expensive gifts. Study 2 replicates this effect for likelihood to give a gift and shows it is not due to social desirability. Studies 3, 4a, and 4b find that guilt over not having provided adequate support drives people to give gifts, and that giving gifts partially relieves givers' feelings of guilt. Studies 5 and 6 examine moderation. In Study 5, people only compensate for a lack of in‐person support with a gift when they have a strong obligation to support the recipient because they are close to them. Study 6 shows that money does not substitute for in‐person support. We show the role of gifts in enhancing givers' wellbeing and provide new customer insights to managers on reasons people purchase gifts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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