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Adjusting to college-Do ability beliefs and confidence in getting support matter for performance and mental health?
No full textEntering college, students are required to adjust to a new academic and social environment. During the COVID-19 pandemic, social interactions with peers and faculty were limited to online settings and access to campus resources was restricted. Hence, students who entered college in fall 2020 began their freshman year under particularly challenging circumstances. We used data from two freshman cohorts, who started college either before or during the pandemic. We investigated to what extent mid-quarter academic and social adjustment (i.e., ability beliefs and confidence in getting support) predicted end-of-quarter performance, psychological distress, and satisfaction of freshman students. Results showed that students who started college during the pandemic were less confident they could get support by peers in the middle of their first quarter. Furthermore, students from the second cohort reported higher psychological distress and lower satisfaction with their adjustment at the end of their first quarter. Results showed that ability beliefs played an important role for end-of-quarter performance, whereas confidence in getting support was more relevant for psychological well-being outcomes in both cohorts
Association of sugar intake from different sources with incident depression in the prospective cohort of UK Biobank participants
No full textAssociations of height, body mass index, and weight gain with breast cancer risk in carriers of a pathogenic variant in BRCA1 or BRCA2: the BRCA1 and BRCA2 Cohort Consortium
No full textAutomated manufacturing and characterization of clinical grade autologous CD20 CAR T cells for the treatment of patients with stage III/IV melanoma
No full textBEHAVIORAL STRATEGIES OF COGNITION IN WILD WESTERN CHIMPANZEES
No full textHumans exhibit the most sophisticated technical and social skills in the animal kingdom. Chimpanzees, like humans, live in complex social systems, have a protracted
developmental period, use tools, and have been shown to express diverse cultures from socially learned behaviors. Chimpanzees, being humans closest living relatives, offer an ideal model to study questions related to human biological and cultural evolution. This thesis aims to investigate how behavioral strategies enable chimpanzees to develop, transmit, and maintain behaviors such as tool use and gestures within their communities, relating these strategies to human evolution. I investigated multiple behaviors in various contexts in four neighboring communities of habituated wild western chimpanzees (Pan troglodytes verus) in the Taï National Park, Côte d’Ivoire. With my first study, I examined the development of manipulative and cognitive skills of chimpanzees using stick tools to extract difficult-to-access foods. Chimpanzees’ acquisition of technical skills extended into adulthood, with more complex tasks taking longer to master. In the second and third studies, I examined whether behaviours previously demonstrated to vary across chimpanzee populations also vary between neighboring communities, and the resulting implications for chimpanzee cultural diversity. My findings highlight that social learning and culture are not partitioned into one or two domains but are likely integral across daily life domains. With the third study, I also demonstrated that in the absence of role models or knowledgeable individuals, cultural behaviors within communities were at risk of disappearing, highlighting the importance of population dynamics and interconnectedness in cultural retention. Together, my findings demonstrate that complex cultural practices might require at the very least prolonged juvenile dependency and brain maturation, such that skill learning continues into adulthood. My observations suggest that humans and chimpanzees may share these traits with our last shared common ancestor
Microglia-Derived Insulin-like Growth Factor 1 Is Critical for Neurodevelopment
No full textInsulin-like growth factor 1 (IGF-1) is a peptide hormone essential for the proper development and growth of the organism, as a complete knockout of Igf1 in mice is lethal, causing microcephaly, growth retardation and the defective development of organs. In the central nervous system, neurons and glia have been reported to express Igf1, but their relative importance for postnatal development has not yet been fully defined. In order to address this, here, we obtained mice with a microglia-specific inducible conditional knockout of Igf1. We show that the deficiency in microglial Igf1, starting in the first postnatal week, leads to body and brain growth retardation, severely impaired myelination, changes in microglia numbers, and behavioral abnormalities. These results emphasize the importance of microglial-derived Igf1 for brain development and function and open new perspectives for the investigation of the role of microglial-Igf1 in neurological diseases
Astrocyte activation in hindlimb somatosensory cortex contributes to electroacupuncture analgesia in acid-induced pain
No full textBackground: Several studies have confirmed the direct relationship between extracellular acidification and the occurrence of pain. As an effective pain management approach, the mechanism of electroacupuncture (EA) treatment of acidification-induced pain is not fully understood. The purpose of this study was to assess the analgesic effect of EA in this type of pain and to explore the underlying mechanism(s).
Methods: We used plantar injection of the acidified phosphate-buffered saline (PBS; pH 6.0) to trigger thermal hyperalgesia in male Sprague–Dawley (SD) rats aged 6–8 weeks. The value of thermal withdrawal latency (TWL) was quantified after applying EA stimulation to the ST36 acupoint and/or chemogenetic control of astrocytes in the hindlimb somatosensory cortex.
Results: Both EA and chemogenetic astrocyte activation suppressed the acid-induced thermal hyperalgesia in the rat paw, whereas inhibition of astrocyte activation did not influence the hyperalgesia. At the same time, EA-induced analgesia was blocked by chemogenetic inhibition of astrocytes.
Conclusion: The present results suggest that EA-activated astrocytes in the hindlimb somatosensory cortex exert an analgesic effect on acid-induced pain, although these astrocytes might only moderately regulate acid-induced pain in the absence of EA. Our results imply a novel mode of action of astrocytes involved in EA analgesia
Asymmetries in cloud microphysical properties ascribed to sea ice leads via water vapour transport in the central Arctic
No full textTo investigate the influence of sea ice openings like leads on wintertime Arctic clouds, the air mass
transport is exploited as a heat and humidity feeding mechanism which can modify Arctic cloud properties.
Cloud microphysical properties in the central Arctic are analysed as a function of sea ice conditions during the
Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in 2019–2020. The
Cloudnet classification algorithm is used to characterize the clouds based on remote sensing observations and the
atmospheric thermodynamic state from the observatory on board the research vessel (RV) Polarstern. To link the
sea ice conditions around the observational site with the cloud observations, the water vapour transport (WVT)
being conveyed towards RV Polarstern has been utilized as a mechanism to associate upwind sea ice conditions
with the measured cloud properties. This novel methodology is used to classify the observed clouds as coupled
or decoupled to the WVT based on the location of the maximum vertical gradient of WVT height relative to the
cloud-driven mixing layer. Only a conical sub-sector of sea ice concentration (SIC) and the lead fraction (LF)
centred on the RV Polarstern location and extending up to 50 km in radius and with an azimuth angle governed
by the time-dependent wind direction measured at the maximum WVT is related to the observed clouds. We
found significant asymmetries for cases when the clouds are coupled or decoupled to the WVT and selected by
LF regimes. Liquid water path of low-level clouds is found to increase as a function of LF, while the ice water
path does so only for deep precipitating systems. Clouds coupled to WVT are found to generally have a lower
cloud base and larger thickness than decoupled clouds. Thermodynamically, for coupled cases the cloud-top
temperature is warmer and accompanied by a temperature inversion at the cloud top, whereas the decoupled cases
are found to be closely compliant with the moist adiabatic temperature lapse rate. The ice water fraction within
the cloud layer has been found to present a noticeable asymmetry when comparing coupled versus decoupled
cases. This novel approach of coupling sea ice to cloud properties via the WVT mechanism unfolds a new tool
to study Arctic surface–atmosphere processes. With this formulation, long-term observations can be analysed
to enforce the statistical significance of the asymmetries. Furthermore, our results serve as an opportunity to
better understand the dynamic linkage between clouds and sea ice and to evaluate its representation in numerical
climate models for the Arctic system
General, Modular Access toward Immobilized Chiral Phosphoric Acid Catalysts and Their Application in Flow Chemistry
No full textChiral phosphoric acids (CPAs) are among the most frequently used organocatalysts, with an ever-increasing number of applications. However, these catalysts are only obtained in a multistep synthesis and are poorly recyclable, which significantly deteriorates their environmental and economic performance. We herein report a conceptually different, general strategy for the direct immobilization of CPAs on a broad scope of solid supports including silica, polystyrene, and aluminum oxide. Solid-state catalysts were obtained in high yields and thoroughly characterized with elemental analysis by inductively coupled plasma-optical emission spectrometry (ICP-OES), nitrogen sorption measurements, thermogravimetric analysis, scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy (STEM/EDX) images, and solid-state NMR spectroscopy. Further, the immobilized catalysts were applied to a variety of synthetically valuable, highly stereoselective transformations under batch and flow conditions including transfer hydrogenations, a Friedländer condensation/transfer hydrogenation sequence, and Mannich reactions under cryogenic flow conditions. Generally, high yields and stereoselectivities were observed along with robust catalyst stability and reusability. After being used for 10 runs under batch conditions, no loss of selectivity or catalytic activity was observed. Under continuous-flow conditions, the heterogeneous system was in operation for 19 h and the high enantioselectivity remained unchanged throughout the entire process. We expect our approach to extend the applicability of CPAs to a higher level, with a focus on flow chemistry and a more environmentally friendly and resource-efficient use of these powerful catalysts