478 research outputs found
Retinal Afferents Synapse with Relay Cells Targeting the Middle Temporal Area in the Pulvinar and Lateral Geniculate Nuclei
Considerable debate continues regarding thalamic inputs to the middle temporal area (MT) of the visual cortex that bypass the primary visual cortex (V1) and the role they might have in the residual visual capability following a lesion of V1. Two specific retinothalamic projections to area MT have been speculated to relay through the medial portion of the inferior pulvinar nucleus (PIm) and the koniocellular layers of the dorsal lateral geniculate nucleus (LGN). Although a number of studies have demonstrated retinal inputs to regions of the thalamus where relays to area MT have been observed, the relationship between the retinal terminals and area MT relay cells has not been established. Here we examined direct retino-recipient regions of the marmoset monkey (Callithrix jacchus) pulvinar nucleus and the LGN following binocular injections of anterograde tracer, as well as area MT relay cells in these nuclei by injection of retrograde tracer into area MT. Retinal afferents were shown to synapse with area MT relay cells as demonstrated by colocalization with the presynaptic vesicle membrane protein synaptophysin. We also established the presence of direct synapes of retinal afferents on area MT relay cells within the PIm, as well as the koniocellular K1 and K3 layers of the LGN, thereby corroborating the existence of two disynaptic pathways from the retina to area MT that bypass V1
Bullying, Safe Schools and Public Health: An Overview in Connecticut Private Schools
Introduction: As evident in the literature, bullying is frequently reported as a public health issue which affects the health and well-being of its victims. Bullying can also negatively impact student academic performance, leading to failure in school as evidenced by high and unacceptable drop-out rates and withdrawals.Objective: This research aimed to examine the issue of bullying from a public health point of view and to assess the issue in a specific region of Connecticutâs private school network. Furthermore, the study will assess the role of a Safe School Climate Coordinator in developing and implementing programs in schoolsthat can serve as effective policy measures to improve school safety with the goal of reducing or eliminating bullying activities in the school environment.Methods: The research employed the qualitative methodology from which six key themes emerged: mental health support; resource constraints; impact and influence of technology and social media; clear definition and distinction of bullying, harassment, and teasing; parental involvement and support; and importance and significance of the networkâs culture. Nine participants from seven private schools in Connecticut took part in semi-structured interviews that were specially designed and conducted by the researchers. The nature of the interviews allowed participants to provide useful insights into the role they played in enhancing school climate by carefully developing and implementing policies and programs that reject violence and promote a school environment that is safe and conducive to learning.Findings: All participants expressed concerns over to the limited mental health services and support that is available within the private school system. All cited the possibility that students are under extreme pressure, and that students are often negatively affected by their home and living environments. These exposures can increase the urge to âact outâ while they are in school. Due to the networkâs strict policy on bullying and any related behavior, there is ongoing monitoring to ensure there is adherence to the requirements. One administrator noted that the individual who was responsible for the Newtown incident had mental health issues.Another administrator opined that recently more referrals have been made to the Department of Children and Families than ever before. There are genuine concerns about what is going on and home environment. When students come into the school environment, they should have a positive outlook and willingness to learn. The message that is conveyed through the interviews is that there is great worry about the future of some students. Mental health support would be helpful in elevating some of the problems that they see in the school environment and work hard to prevent.Conclusion: Where bullying is concerned, the public health toll is great and can have physical and emotional effects throughout the life of those who participate or are targeted. All efforts made to mitigate these deleterious effects in the early years of child and adolescence development is paramount in supporting the psychological well-being of the students
When the Personal Vote Is Not Enough: The Failure of Charter Reform in Columbia, South Carolina
The choice of city structure is one of the most important choices that citizens and elected representatives face in local government. While we know a good deal about the macro-level trends in a city structure, we know comparatively less about why residents in individual cities may opt for one structure or another. In this paper, we focus on the unsuccessful 2013 single-issue referendum in Columbia, South Carolina, addressing why, despite support from key players, the city chose not to adopt a strong-mayor form of government. Using precinct-level data, we find support for the personal vote hypothesis. We discover that support for the sitting mayor is a significant predictor of support for reform, although the lack of voter mobilization city-wide may be too much of a factor for reform advocates to overcome. This investigation leads us to a number of conclusions that are relevant for both academics and practitioners who want to understand structural change in local government
A Review of 2011 for PLoS Computational Biology
A Review of 2011 for <em>PLoS Computational Biology</em
Megakaryocyte NLRP3 hyperactivation induces mild anemia and potentiates inflammatory response in mice
BackgroundThe NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome has been described in both immune cells and platelets, but its role in the megakaryocyte (MK) lineage remains elusive.ObjectiveThe aim of this study was to explore the role of NLRP3 inflammasome in megakaryocytes and platelets.MethodsWe generated Nlrp3A350V/+/Gp1ba-CreKI/+ mice carrying a mutation genetically similar to the one observed in human MuckleâWells syndrome, which leads to hyperactivity of NLRP3 specifically in MK and platelets.ResultsPlatelets from the mutant mice expressed elevated levels of both precursor and active form of caspase-1, suggesting hyperactivity of NLRP3 inflammasome. Nlrp3A350V/+/Gp1ba-CreKI/+ mice developed normally and had normal platelet counts. Expression of major platelet receptors, platelet aggregation, platelet deposition on collagen under shear, and deep vein thrombosis were unchanged. Nlrp3A350V/+/Gp1ba-CreKI/+ mice had mild anemia, reduced Ter119+ cells in the bone marrow, and splenomegaly. A mild increase in MK TGF-ÎČ1 might be involved in the anemic phenotype. Intraperitoneal injection of zymosan in Nlrp3A350V/+/Gp1ba-CreKI/+ mice induced increased neutrophil egression and elevated levels of a set of proinflammatory cytokines, alongside IL-10 and G-CSF, in the peritoneal fluid as compared with control animals.ConclusionMK/platelet NLRP3 inflammasome promotes the acute inflammatory response and its hyperactivation in mice leads to mild anemia and increased extramedullary erythropoiesis
Recommended from our members
Direct synthesis of multiplexed metal nanowire based devices using carbon nanotubes as vector templates
We present the synthesis of metal nanowires in a multiplexed device configuration using singleâwalled carbon nanotubes (SWNTs) as nanoscale vector templates. The SWNT templates control the dimensionality of the wires, allowing precise control of their size, shape and orientation; moreover a solution processable approach enables their linear deposition between specific electrode pairs in electronic devices. Electrical characterizations demonstrate the successful fabrication of metal nanowire electronic devices, while multiscale characterization of the different fabrication steps reveals details of the structure and charge transfer between the material encapsulated and the carbon nanotube. Overall the strategy presented allows facile, lowâcost and direct synthesis of multiplexed metal nanowire devices for nanoelectronic applications
The Early Postnatal Nonhuman Primate Neocortex Contains Self-Renewing Multipotent Neural Progenitor Cells
The postnatal neocortex has traditionally been considered a non-neurogenic region, under non-pathological conditions. A few studies suggest, however, that a small subpopulation of neural cells born during postnatal life can differentiate into neurons that take up residence within the neocortex, implying that postnatal neurogenesis could occur in this region, albeit at a low level. Evidence to support this hypothesis remains controversial while the source of putative neural progenitors responsible for generating new neurons in the postnatal neocortex is unknown. Here we report the identification of self-renewing multipotent neural progenitor cells (NPCs) derived from the postnatal day 14 (PD14) marmoset monkey primary visual cortex (V1, striate cortex). While neuronal maturation within V1 is well advanced by PD14, we observed cells throughout this region that co-expressed Sox2 and Ki67, defining a population of resident proliferating progenitor cells. When cultured at low density in the presence of epidermal growth factor (EGF) and/or fibroblast growth factor 2 (FGF-2), dissociated V1 tissue gave rise to multipotent neurospheres that exhibited the ability to differentiate into neurons, oligodendrocytes and astrocytes. While the capacity to generate neurones and oligodendrocytes was not observed beyond the third passage, astrocyte-restricted neurospheres could be maintained for up to 6 passages. This study provides the first direct evidence for the existence of multipotent NPCs within the postnatal neocortex of the nonhuman primate. The potential contribution of neocortical NPCs to neural repair following injury raises exciting new possibilities for the field of regenerative medicine
Ten Simple Rules for Effective Computational Research
<p>Ten Simple Rules for Effective Computational Research</p
The evolution of the dust and gas content in galaxies
We use deep Herschel observations taken with both PACS and SPIRE imaging cameras to estimate the dust mass of a sample of galaxies extracted from the GOODS-S, GOODS-N and the COSMOS fields. We divide the redshiftâstellar mass (M star )âstar formation rate (SFR) parameter space into small bins and investigate average properties over this grid. In the first part of the work we investigate the scaling relations between dust mass, stellar mass and SFR out to z = 2.5. No clear evolution of the dust mass with redshift is observed at a given SFR and stellar mass. We find a tight correlation between the SFR and the dust mass, which, under reasonable assumptions, is likely a consequence of the Schmidt-Kennicutt (S-K) relation. The previously observed correlation between the stellar content and the dust content flattens or sometimes disappears when considering galaxies with the same SFR. Our finding suggests that most of the correlation between dust mass and stellar mass obtained by previous studies is likely a consequence of the correlation between the dust mass and the SFR combined with the main sequence, i.e., the tight relation observed between the stellar mass and the SFR and followed by the majority of star-forming galaxies. We then investigate the gas content as inferred from dust mass measurements. We convert the dust mass into gas mass by assuming that the dust-to-gas ratio scales linearly with the gas metallicity (as supported by many observations). For normal star-forming galaxies (on the main sequence) the inferred relation between the SFR and the gas mass (integrated S-K relation) broadly agrees with the results of previous studies based on CO measurements, despite the completely different approaches. We observe that all galaxies in the sample follow, within uncertainties, the same S-K relation. However, when investigated in redshift intervals, the S-K relation shows a moderate, but significant redshift evolution. The bulk of the galaxy population at z ⌠2 converts gas into stars with an efficiency (star formation efficiency, SFE = SFR/M gas , equal to the inverse of the depletion time) about 5 times higher than at z ⌠0. However, it is not clear what fraction of such variation of the SFE is due to an intrinsic redshift evolution and what fraction is simply a consequence of high-z galaxies having, on average, higher SFR, combined with thesuper-linear slope of the S-K relation (whileother studies finda linear slope). We confirm that the gas fraction (f gas = M gas /(M gas + M star )) decreases with stellar mass and increases with the SFR. We observe no evolution with redshift once M star and SFR are fixed. We explain these trends by introducing a universal relation between gas fraction, stellar mass and SFR that does not evolve with redshift, at least out to z ⌠2.5. Galaxies move across this relation as their gas content evolves across the cosmic epochs. We use the 3D fundamental f gas âM star âSFR relation, along with the evolution of the main sequence with redshift, to estimate the evolution of the gas fraction in the average population of galaxies as a function of redshift and as a function of stellar mass: we find that M star > ⌠10 11 M ? galaxies show the strongest evolution at z > ⌠1.3 and a flatter trend at lower redshift, while f gas decreases more regularly over the entire redshift range probed in M star < ⌠10 11 Mo galaxies, in agreement with a downsizing scenario
Continuous catalytic upgrading of ethanol to n-butanol and >C-4 products over Cu/CeO2 catalysts in supercritical CO2
n-Butanol (BuOH) often has superior properties as a bio-fuel compared to ethanol (EtOH). However finding sustainable sources of BuOH is proving difficult. In this paper, direct production of BuOH from EtOH is compared over custom-synthesized six Cu catalysts, supported on different solid acids. These catalysts were tested in a continuous flow supercritical CO2 (scCO2) reactor, and were found to catalyse the dehydrogenation, aldol condensation and hydrogenation steps of the so-called Guerbet reaction converting EtOH to BuOH. BuOH yields and selectivities were significantly different over the four catalysts. Cu on high surface area CeO2 showed the best activity for BuOH formation, with yields above 30% achieved with good selectivity. In addition high pressure CO2 is shown to have a positive effect on the reaction, possibly due to the redox cycle of Ce2O3 and CeO2
- âŠ