339 research outputs found
Autophagy in motor neuron disease: Key pathogenetic mechanisms and therapeutic targets
Autophagy is a lysosome-dependant intracellular degradation process that eliminates long-lived proteins as well as damaged organelles from the cytoplasm. An increasing body of evidence suggests that dysregulation of this system plays a pivotal role in the etiology and/or progression of neurodegenerative diseases including motor neuron disorders. Herein, we review the latest findings that highlight the involvement of autophagy in the pathogenesis of amyotrophic lateral sclerosis (ALS) and the potential role of this pathway as a target of therapeutic purposes. Autophagy promotes the removal of toxic, cytoplasmic aggregate-prone pathogenetic proteins, enhances cell survival, and modulates inflammation. The existence of several drugs targeting this pathway can facilitate the translation of basic research to clinical trials for ALS and other motor neuron diseases
Blue and grey urban water footprints through citizens’ perception and time series analysis of Brazilian dynamics
This is an Accepted Manuscript of an article published by Taylor & Francis in Hydrological Sciences Journal on 4 March 2021, available online: https://doi.org/10.1080/02626667.2021.1879388Predicting future water demands of societies is a major challenge because it involves a holistic understanding of possible changes within socio-hydrological systems. Although recent research has made efforts to translate social dimensions into the analysis of hydrological systems, few studies have involved citizen participation in water footprint analysis. This paper integrates time series with citizens’ perceptions, knowledge and beliefs concerning sanitation elements to account for municipal blue and grey water footprints in São Carlos, Brazil, from 2009 to 2016, and potential water footprints in 2030 and 2050. In this case study, grey footprint potentially exceeds the blue water footprint by up to 35 times, and volunteered information suggested a reduction in water consumption, larger garbage production and greater investment in sanitation infrastructure from authorities. We conclude that public knowledge can be used to delineate possible water footprint scenarios and reveal paradoxes in the coevolution of socio-hydrological systems on an urban scale
A magneto-optic trap using a reversible, solid-state alkali-metal source
We demonstrate a novel way to form and deplete a vapor-cell magneto-optic
trap (MOT) using a reversible, solid-state alkali-metal source (AMS) via an
applied polarized voltage. Using ~100 mW of electrical power, a trapped-atom
number of 5x10^6 has been achieved starting from near zero and the timescales
of the MOT formation and depletion of ~1 s. This fast, reversible, and low
power alkali-atom source is desirable in both tabletop and portable cold-atom
systems. The core technology of this device should translate readily to other
alkali and alkaline-earth elements that could find a wide range of uses in
cold-atom systems and instruments.Comment: 7 page
Dynamic characterization of an alkali-ion battery as a source for laser-cooled atoms
We investigate a solid-state, reversible, alkali-ion battery (AIB) capable of
regulating the density of alkali atoms in a vacuum system used for the
production of laser-cooled atoms. The cold-atom sample can be used with
in-vacuum chronoamperometry as a diagnostic for the voltage-controlled
electrochemical reaction that sources or sinks alkali atoms into the vapor. In
a combined reaction-diffusion-limited regime, we show that the number of
laser-cooled atoms in a magneto-optical trap can be increased both by initially
loading the AIB from the vapor for longer, and by using higher voltages across
the AIB when atoms are subsequently sourced back into the vapor. The time
constants associated with the change in atom number in response to a change in
AIB voltage are in the range of 0.5 s - 40 s. The AIB alkali reservoir is
demonstrated to survive oxidization during atmospheric exposure, simplifying
reservoir loading prior to vacuum implementation as a replacement for
traditional resistively-heated dispensers. The AIB capabilities may provide an
improved atom number stability in next-generation atomic clocks and sensors,
while also facilitating fast loading and increased interrogation times.Comment: 7 pages, 5 figure
Los mosquitos del estado de Quintana Roo, MĂ©xico (Diptera: Culicidae).
A study on the distribution of the mosquitoes of Quintana Roo State of MĂ©xico was carried out by collecting immature and adult stages during September and October 2006. The collections were made from different locations in the three physiogeographical provinces of the state: Carso Yucateco, Carso, LomerĂos de Campeche, and Costa Baja de Quintana Roo. A total of 420 larvae, 294 pupae, and 726 adults representing 13 genera and 41 species were collected. Two genera, three subgenera, and 11 species are new to the mosquito fauna of Quintana Roo State. Collection and bionomical data are included for species collected during the study, and a checklist of species newly and previously recorded from the state is provided.Un estudio de la distribuciĂłn de los mosquitos del estado de Quintana Roo, MĂ©xico fue realizado por medio de colectas de estados inmaduros y adultos durante Septiembre y Octubre del 2006. Las colectas fueron realizadas en diferentes localidades de las tres provincias fisiográficas del estado: Carso Yucateco, Carso, LomerĂos de Campeche y Costa Baja de Quintana Roo. Un total de 420 larvas, 294 pupas y 726 adultos fueron colectados representando 13 gĂ©neros y 41 especies. Dos gĂ©neros, tres subgĂ©neros y 11 especies son nuevos registros estatales para Quintana Roo
Neuronal Agrin Promotes Proliferation of Primary Human Myoblasts in an Age-Dependent Manner
Neuronal agrin, a heparan sulphate proteoglycan secreted by the -motor neurons, promotes the formation and maintenance of the neuromuscular junction by binding to Lrp4 and activating muscle-specific kinase (MuSK). Neuronal agrin also promotes myogenesis by enhancing differentiation and maturation of myotubes, but its effect on proliferating human myoblasts, which are often considered to be unresponsive to agrin, remains unclear. Using primary human myoblasts, we determined that neuronal agrin induced transient dephosphorylation of ERK1/2, while c-Abl, STAT3, and focal adhesion kinase were unresponsive. Gene silencing of Lrp4 and MuSK markedly reduced the BrdU incorporation, suggesting the functional importance of the Lrp4/MuSK complex for myoblast proliferation. Acute and chronic treatments with neuronal agrin increased the proliferation of human myoblasts in old donors, but they did not affect the proliferation of myoblasts in young donors. The C-terminal fragment of agrin which lacks the Lrp4-binding site and cannot activate MuSK had a similar age-dependent effect, indicating that the age-dependent signalling pathways activated by neuronal agrin involve the Lrp4/MuSK receptor complex as well as an Lrp4/MuSK-independent pathway which remained unknown. Collectively, our results highlight an age-dependent role for neuronal agrin in promoting the proliferation of human myoblasts
Risk perception and vulnerability of value: a study in the context of commercial property sector
© 2016 The Author(s). Published by Vilnius Gediminas Technical University (VGTU) Press, and Taylor & Francis. The research was developed linking the impact of flood risk on utility, desirability and marketability related to vulnerability of commercial property value. Likert style questionnaire survey was conducted to obtain data from flood affected and un-affected respondents across different designated flood risk zones on key business and perception variables among two groups of business property holders in England. The responses were analysed through a spatial vulnerability model to illustrate the distribution of the vulnerability of value of properties among flood plain business holders on a GIS platform. Majority of respondents perceived that utility of properties may be hampered by flooding and subsequently have an impact on value for property at risk. Those with flood experience gave greater weight to their specific business needs such as the prime location and expected income level than those without flood experience. The implication of the study lies in understanding that flood risk perceptions can shape actions of people at risk towards future increase in resilience having strategic impact on value of property saleability in the future
Sedimentology and stratigraphy of the ANDRILL McMurdo Ice Shelf (AND-1B) core
During the 2006-2007 austral summer, the ANDRILL McMurdo Ice Shelf Project recovered a core 1285 m long (AND-1B) from Windless Bight in McMurdo Sound. This core contains a range of lithologies, including both siliciclastic and volcanic diamictites, sandstones and mudstones; diatomites; and volcanic ash/tuff and one phonolitic lava flow. This sequence has been subdivided into eight lithostratigraphic units and 25 subunits, based on lithological abundances. Eleven lithofacies have been identified, ranging from open marine diatomites and mudstones to turbidites to ice-proximal massive and stratified diamictites. More than 50 glacimarine sequences have been recognized, bounded by glacial surfaces of erosion. Three distinct stacking patterns are present, showing evidence of glacial advance/retreat/advance with varying degrees of preservation. Carbonate and pyrite are the dominant secondary phases in the core. The pyrite overprint is especially notable in volcanic sediments below ~400 mbsf, where it often obscures stratification and sediment texture
Sedimentology and stratigraphy of the ANDRILL McMurdo Ice Shelf (AND-1B) core
During the 2006-2007 austral summer, the ANDRILL McMurdo Ice Shelf Project recovered a core 1285 m long (AND-1B) from Windless Bight in McMurdo Sound. This core contains a range of lithologies, including both siliciclastic and volcanic diamictites, sandstones and mudstones; diatomites; and volcanic ash/tuff and one phonolitic lava flow. This sequence has been subdivided into eight lithostratigraphic units and 25 subunits, based on lithological abundances. Eleven lithofacies have been identified, ranging from open marine diatomites and mudstones to turbidites to ice-proximal massive and stratified diamictites. More than 50 glacimarine sequences have been recognized, bounded by glacial surfaces of erosion. Three distinct stacking patterns are present, showing evidence of glacial advance/retreat/advance with varying degrees of preservation. Carbonate and pyrite are the dominant secondary phases in the core. The pyrite overprint is especially notable in volcanic sediments below ~400 mbsf, where it often obscures stratification and sediment texture
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