Micro y nanocanales integrados: nuevas herramientas para control de movimiento molecular

This paper presents a review of work on the fabrication and use of nanochannels in silicon and polymers for the control of molecular transport. The method of Sacrifi cial Layer Lithography is reviewed and demonstrated for silicon and polymers. A novel technique for the productions of conical nanopores through a polymer membrane is also reviewed. Nanochannels and nanopores have many potential applications for drug delivery, immunoprotection of cell implants, blocking of globular proteins from biosensor surfaces, and diagnostic devices. All of these applications benefi t from the more direct interactions of devices with biomolecules.El presente trabajo presenta una revisión literaria sobre los métodos de fabricación de nanocanales en silicio y diferentes materiales poliméricos; y su uso en control de transporte molecular. Se describe el método “Sacrifi cial Layer Lithography” para silicio y polímeros. Adicionalmente, una novedosa técnica para la producción de nanoporos cónicos a través de una membrana polimérica es descrita. Los nanocanales y los nanoporos poseen diversas aplicaciones potenciales en la liberación de drogas, en la inmunoprotección de implantes celulares, el bloqueo de proteínas globulares en la superfi cie de biosensores, y en dispositivos para diagnóstico. Todas estas aplicaciones se benefi cian de la interacción directa entre los dispositivos y las biomoléculas

The suppression of fluorescence peaks in energy-dispersive X-ray diffraction

A novel method to separate diffraction and fluorescence peaks in energy- dispersive X-ray diffraction (EDXRD) is described. By tuning the excitation energy of an X-ray tube source to just below an elemental absorption edge, the corresponding fluorescence peaks of that element are completely suppressed in the resulting spectrum. Since Bremsstrahlung photons are present in the source spectrum up to the excitation energy, any diffraction peaks that lie at similar energies to the suppressed fluorescence peaks are uncovered. This technique is an alternative to the more usual method in EDXRD of altering the scattering angle in order to shift the energies of the diffraction peaks. However, in the back-reflection EDXRD technique [Hansford (2011). J. Appl. Cryst. 44, 514–525] changing the scattering angle would lose the unique property of insensitivity to sample morphology and is therefore an unattractive option. The use of fluorescence suppression to reveal diffraction peaks is demonstrated experimentally by suppressing the Ca K fluorescence peaks in the back-reflection EDXRD spectra of several limestones and dolomites. Three substantial benefits are derived: uncovering of diffraction peak(s) that are otherwise obscured by fluorescence; suppression of the Ca K escape peaks; and an increase in the signal-to-background ratio. The improvement in the quality of the EDXRD spectrum allows the identification of a secondary mineral in the samples, where present. The results for a pressed-powder pellet of the geological standard JDo-1 (dolomite) show the presence of crystallite preferred orientation in this prepared sample. Preferred orientation is absent in several unprepared limestone and dolomite rock specimens, illustrating an advantage of the observation of rocks in their natural state enabled by back-reflection EDXRD

The Lonely Scroll: The Impact of Social Media on Loneliness in Introverts and Extroverts

This study examined the impact that social media had on feelings of loneliness in introverts and extroverts. Each participant received a survey based off of the NEO Personality Inventory, the UCLA Loneliness Scale and the Internet Behaviors Scale. The survey aimed to assess the relationship between social media and feelings of loneliness on different personality types. Social Media is a prevalent aspect of modern day culture. Therefore, this study aims to teach individuals how to prevent social media from negatively affecting them. The results supported our hypotheses that both loneliness and internet use, as well as, personality type and loneliness are statistically significant

Median eminence myelin continuously turns over in adult mice

OBJECTIVE: Oligodendrocyte progenitor cell differentiation is regulated by nutritional signals in the adult median eminence (ME), but the consequences on local myelination are unknown. The aim of this study was to characterize myelin plasticity in the ME of adult mice in health or in response to chronic nutritional challenge and determine its relevance to the regulation of energy balance. METHODS: We assessed new oligodendrocyte (OL) and myelin generation and stability in the ME of healthy adult male mice using bromodeoxyuridine labelling and genetic fate mapping tools. We evaluated the contribution of microglia to ME myelin plasticity in PLX5622-treated C57BL/6J mice and in Pdgfra-Cre/ERT2;R26R-eYFP;Myrffl/fl mice, where adult oligodendrogenesis is blunted. Next, we investigated how high-fat feeding or caloric restriction impact ME OL lineage progression and myelination. Finally, we characterized the functional relevance of adult oligodendrogenesis on energy balance regulation. RESULTS: We show that myelinating OLs are continuously and rapidly generated in the adult ME. Paradoxically, OL number and myelin amounts remain remarkably stable in the adult ME. In fact, the high rate of new OL and myelin generation in the ME is offset by continuous turnover of both. We show that microglia are required for continuous OL and myelin production, and that ME myelin plasticity regulates the recruitment of local immune cells. Finally, we provide evidence that ME myelination is regulated by the body's energetic status and demonstrate that ME OL and myelin plasticity are required for the regulation of energy balance and hypothalamic leptin sensitivity. CONCLUSIONS: This study identifies a new mechanism modulating leptin sensitivity and the central control of energy balance and uncovers a previously unappreciated form of structural plasticity in the ME

UC-248 GTRI: IT Management Web Application

This application was part of an industry Capstone project with Georgia Tech Research Institute, with Mr. Matthew Pinkston as the industry sponsor, Ms. Allison Boyle as the industry Capstone coordinator, and Mr. Donald Privitera as the Capstone professor. Our team worked on creating the framework for an opensource, web-based IT management application that future developers can add various features and sub-applications onto for purposes such as asset and budget management. The application is PHP-based with its backend, utilizing the Laravel framework and several of its built-in features for routing, database management, login authentication with bcrypt hash security, and session tracking. The frontend design of the web application was done using HTML, Bootstrap, and jQuery. MySQL was used for the database, which is currently used primarily for the user authentication system. We have chosen the MIT licensing model to ensure future developers can easily add onto the code and incorporate sub-applications into our framework, which was created with the intent of being a basis for developers to add functionality to as they see fit. It also ensures the application serves as a free, opensource solution for small IT management departments

Novel clone selection technique reveals heterogeneity among HEK293T cells engineered to produce therapeutic extracellular vesicles

HEK293T cells have been engineered to produce extracellular vesicles (EVs) that deliver miR-199a-3p to CD44+ hepatocellular carcinoma cells. Restoration of this miRNA has been shown to slow cancer progression in-vitro. Isolation and analysis of EVs from cell culture media containing selection agent revealed that the number of miRNA-199a-3p copies was less than the number of cells in culture suggesting that not all cells produce therapeutic EVs. Therefore, therapeutic EV production can be significantly increased by selecting the HEK293T clones that produce the most therapeutic EVs. While clone selection is traditionally accomplished by cell analysis techniques such as fluorescence activated cell sorting (FACS), detection of therapeutic EVs poses a unique challenge in that cellular expression of miRNA-199a-3p does not necessarily correlate to the amount of exosomal miRNA-199a-3p. In response to this challenge, a fibrous microwell array was developed to screen thousands of clones for therapeutic EV productivity (figure 1). The fibrous microwell system is able to evaluate cell growth rate under fluid shear stress, EV productivity and EV characterization using fluorescently labeled antibodies or cationic lipoplex nanoparticles (detect presence of miRNA-199a-3p inside captured EVs produced by single clones). The most productive clones can be released from the microwells and grown in large scale cell culture to significantly increase therapeutic EV production. Please click Additional Files below to see the full abstract

Distinct Neural Signatures of Multimodal Resizing Illusions

Illusory body resizing typically uses multisensory integration to change the perceived size of a body part. Previous studies associate these multisensory body illusions with frontal theta oscillations and parietal gamma oscillations for dis-integration and integration of multisensory signals, respectively. However, recent studies also support illusory changes of embodiment from unimodal visual stimuli. This preregistered study (N=48) investigated differences between multisensory visuo-tactile and unimodal visual resizing illusions using EEG, to gain a more comprehensive understanding of the neural underpinnings of resizing illusions in a healthy population. We hypothesised (1) stronger illusion in multisensory compared to unimodal, and unimodal compared to incongruent (dis-integration) conditions, (2) greater parietal gamma during multisensory compared to unimodal, and (3) greater frontal theta during incongruent compared to baseline conditions. Subjective Illusory results partially support Hypothesis 1, showing a stronger illusion in multisensory compared to unimodal conditions, but finding no significant difference comparing unimodal to incongruent conditions. Results partially supported EEG hypotheses, finding increased parietal gamma activity comparing multisensory to unimodal visual conditions, whilst finding increased parietal theta activity when comparing incongruent to non-illusion conditions. While results demonstrated that only 27% of participants experienced the stretching illusion with unimodal visual stimuli compared to 73% of participants experiencing the stretching illusion in the multisensory condition, further analysis suggested that those who experience visual-only illusions exhibit a different neural signature to those who do not, with activity focussed around frontal and parietal regions early on in the illusory manipulation, compared to activity focussed more over parietal regions and at a later point in the illusory manipulation for the full sample of participants. Our results support the importance of multisensory integration for illusory changes in perceived body size. However, we also suggest that unimodal visual illusions can influence cortical body representations for just over one in four participants, which may have implications for the development of accessible unimodal visual chronic pain treatments

Psychological distress among primary school teachers: a comparison with clinical and population samples

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Objectives: This analysis explored the level of psychological distress among primary school teachers in the South West of England as compared to clinical and general population samples. Study design: Secondary analysis of data from the Supporting Teachers And childRen in Schools (STARS) trial completed by up to 90 teachers at baseline, 9, 18 and 30 months of follow up. Methods: We used the Everyday Feelings Questionnaire (EFQ) as a measure of psychological distress. Baseline data on teachers were compared with a population sample of professionals and a clinical sample of patients attending a depression clinic. Results: Our teacher cohort experienced higher levels of psychological distress than comparable professionals from the general population, which were sustained over 30 months follow-up. Levels of psychological distress were lower than those found in the clinical sample. Using a cut-point indicative of moderate depression, our data suggest between 19% and 29% of teachers experienced clinically significant distress at each time-point. Conclusions: We detected high and sustained levels of psychological distress among primary school teachers, which suggests an urgent need for intervention. Effective support for teachers’ mental health is particularly important given the potential impact of poor teacher mental health on pupil wellbeing, pupil attainment and teacher-pupil relationships.The STARS trial was funded by the National Institute for Health Research Public Health Research Programme (project number 10/3006/07) and the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula