679 research outputs found
Optovibrometry: tracking changes in the surface tension and viscosity of multicomponent droplets in real-time
An instrument was developed for measuring real time changes in the surface tension and viscosity of multicomponent droplets of miscible liquids and other soft materials. Droplets containing glycerol and water were supported on superamphiphobic surfaces and vibrated by applying a short mechanical impulse. Laser light was refracted through the droplets and allowed to fall on the surface of a photodiode. Time dependent variations in the intensity measured by the photodiode during vibration were used to monitor the decay of the droplet oscillations. The frequencies and spectral widths of the droplet vibrational resonances were then obtained from Fourier transforms of these time dependent intensity signals. A recently developed model of viscoelastic droplet vibration was used along with these values and measurements of the drop dimensions to extract the surface tension and viscosity of the drops as they evaporated. Collection of data was automated and values of frequency, spectral width, drop size, surface tension and viscosity were obtained with a time resolution of three seconds over a period of thirty minutes. The values of surface tension and viscosity obtained were shown to be in good agreement with literature values obtained from bulk glycerol/water solutions; thus validating the technique for wider application to other multicomponent liquids and soft matter systems
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Ni Royaliste ni Ligueuse: La République de Saint-Malo
While most French cities, including Troyes and Rouen, suffered during the French Wars of Religion, the Breton port town of Saint-Malo thrived after its leaders planned and successfully executed the seizure of its château in March 1590. Having declared independence at that time, city leaders engaged in diplomatic and military maneuvers to secure the physical and economic security of the city. At the same time, the leaders took steps to fend off potential attempts by both governor and bishop to undermine their authority.
This paper briefly outlines key events during the Wars of Religion before examining the behavior of city leaders in Rouen and Troyes to understand how their decisions impacted the wellbeing of their fellow citizens, while navigating tricky relationships with the king on the one hand and the Catholic League on the other. I then examine the actions of municipal authorities in Saint-Malo in an attempt to understand how they worked to obtain the best solutions to promote the security of their city. While Malouin leaders may not have acted with the specific intent to increase their political capital vis-à-vis Henri IV, when the time came to negotiate with the king regarding the terms of their return to the French fold, they did so with a power that far exceeded that of Rouen and Troyes.</p
Personalised E-Learning: Facilitating Students\u27 Understanding and Mastery of New Concepts
Each individual perceives and experiences life and learning in their own unique way. Past experiences can influence our understanding and mastery of new concepts. Occasionally, learners meet obstacles in their learning experiences which they find difficult to surmount.Not all learners require the same learning experience to reach the required thresholds or basic units of understanding which are expected to succeed with their course of study. Threshold concepts are part of the fundamentals of a subject which one builds upon to eventually achieve the required learning outcomes. The provision of personalised e-learning resources to assist students to surmount their personal learning difficulties could improve student engagement with the required threshold concepts and therefore assist each individual student in achieving their full potential. Tailored learning experiences which have been specifically selected to suit individual students learning requirements could be made available to the students who felt a need to use these resources to help them through frustrating times on route to grasping new concepts. This research reviews the functionality which non-technical educators would need to enable them to create personalised learning resources. The objective is to develop an authoring package which will enable non-technical authors create personalised learning resources and activities. These personalised e-learning resources and activities could be used to assist students in grasping a deeper understanding of the threshold concepts required for their discipline. A deeper understanding of the fundamental topics will help students during their progression through the rest of the curriculum and course of study. The authoring package for personalising e-learning should facilitate the creation of personalised learning resources and activities by non-technical authors. A modular approach will be undertaken in the development of this authoring package and evaluations will be conducted on completion of each module. An overall evaluation of this authoring package for personalising e-learning will be undertaken once the package is complete
Tell someone, don't keep it to yourself: a study into the mental health needs of Gypsy and Traveller Communities in Bolton using a Community Engagement Approach
Enhanced LH action in transgenic female mice expressing hCGβ-subunit induces pituitary prolactinomas; the role of high progesterone levels
The etiology of pituitary adenomas remains largely unknown, with the exception of involvement of estrogens in the formation of prolactinomas. We have examined the molecular pathogenesis of prolactin-producing pituitary adenomas in transgenic female mice expressing the human choriongonadotropin (hCG) β-subunit. The LH/CG bioactivity is elevated in the mice, with consequent highly stimulated ovarian progesterone (P4) production, in the face of normal estrogen secretion. Curiously, despite normal estrogen levels, large prolactinomas developed in these mice, and we provide here several lines of evidence that the elevated P4 levels are involved in the growth of these estrogen-dependent tumors. The antiprogestin mifepristone inhibited tumor growth, and combined postgonadectomy estradiol/P4 treatment was more effective than estrogen alone in inducing tumor growth. Evidence for direct growth-promoting effect of P4 was obtained from cultures of primary mouse pituitary cells and rat somatomammotroph GH3 cells. The mouse tumors and cultured cells revealed stimulation of the cyclin D1/cyclin-dependent kinase 4/retinoblastoma protein/transcription factor E2F1 pathway in the growth response to P4. If extrapolated to humans, and given the importance of endogenous P4 and synthetic progestins in female reproductive functions and their pharmacotherapy, it is relevant to revisit the potential role of these hormones in the origin and growth of prolactinomas
Convergent evolution of pregnancy-specific glycoproteins in human and horse
Pregnancy-specific glycoproteins (PSGs) are members of the carcinoembryonic antigen cell adhesion molecule (CEACAM) family that are secreted by trophoblast cells. PSGs may modulate immune, angiogenic and platelet responses during pregnancy. Until now, PSGs are only found in species that have a highly invasive (hemochorial) placentation including humans, mice and rats. Surprisingly, analyzing the CEACAM gene family of the horse, which has a non-invasive epitheliochorial placenta, with the exception of the transient endometrial cups, we identified equine CEACAM family members that seem to be related to PSGs of rodents and primates. We identified seven genes that encode secreted PSG-like CEACAMs. Phylogenetic analyses indicate that they evolved independently from an equine CEACAM1-like ancestor rather than from a common PSG-like ancestor with rodents and primates. Significantly, expression of PSG-like genes (CEACAM44, CEACAM48, CEACAM49 and CEACAM55) was found in non-invasive as well as invasive trophoblast cells such as purified chorionic girdle cells and endometrial cup cells. Chorionic girdle cells are highly invasive trophoblast cells that invade the endometrium of the mare where they form endometrial cups and are in close contact with maternal immune cells. Therefore, the microenvironment of invasive equine trophoblast cells has striking similarities to the microenvironment of trophoblast cells in hemochorial placentas, suggesting that equine PSG-like CEACAMs and rodent and primate PSGs have undergone convergent evolution. This is supported by our finding that equine PSG-like CEACAM49 exhibits similar activity to certain rodent and human PSGs in a functional assay of platelet–fibrinogen binding. Our results have implications for understanding the evolution of PSGs and their functions in maternal–fetal interactions
Garcinia kola and garcinoic acid suppress SARS-CoV-2 spike glycoprotein S1-induced hyper-inflammation in human PBMCs through inhibition of NF-κB activation
Coarse Coding and Discourse Comprehension in Adults with Right Hemisphere Brain Damage
This study assessed whether right-hemisphere-damaged (RHD) adults’ priming of peripheral semantic features of nouns was associated with their discourse comprehension performance. A subset of RHD participants who were particularly poor comprehenders of implied information in discourse were also poor at sustaining activation for peripheral semantic features of nouns, relative to good RHD comprehenders. This result is consistent with a variant of the ‘coarse coding’ hypothesis of discourse comprehension in RHD. Continued research on RHD adults’ communicative strengths and weaknesses will have future implications for clinical assessment and management
Dicer loss and recovery induce an oncogenic switch driven by transcriptional activation of the oncofetal Imp1–3 family
MicroRNAs(miRNAs) are post-transcriptional regulators of gene expressioncritical for organismal viability. Changes inmiRNAactivity arecommonin cancer, buthowthese changes relate to subsequent alterations in transcription and the process of tumorigenesis is not well understood. Here, we report a deep transcriptional, oncogenic network regulated bymiRNAs. Wepresent analysis of the gene expression and phenotypic changes associated with globalmiRNA restoration in miRNA-deficient fibroblasts. This analysis uncovers a miRNA-repressed network containing oncofetal genesImp1, Imp2, and Imp3(Imp1–3) that is up-regulated primarily transcriptionally > 100-fold uponDicer loss and is resistant to resilencing by complete restoration of miRNA activity. This Dicer-resistant epigenetic switch confers tumorigenicity to these cells. Let-7 targets Imp1–3 are required for this tumorigenicity and feed back to reinforce and sustain expression of the oncogenic network. Together, these Dicer-resistant genes constitute an mRNA expression signature that is present in numerous human cancers and is associated with poor survival.United States. Public Health Service (Grant R01CA133404)National Cancer Institute (U.S.) (Grant P01CA42063)Marie D. and Pierre Casimir-Lamber
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