1,603 research outputs found
Aluminum nitride for heatspreading in RF IC’s
To reduce the electrothermal instabilities in silicon-on-glass high-frequency bipolar devices, the integration of thin-film aluminum nitride as a heatspreader is studied. The AlN is deposited by reactive sputtering and this material is shown to fulfill all the requirements for actively draining heat from RF IC’s, i.e., it has good process compatibility, sufficiently high thermal conductivity and good electrical isolation also at high frequencies. The residual stress and the piezoelectric character of the material, both of which can be detrimental for the present application, are minimized by a suitable choice of deposition conditions including variable biasing of the substrate in a multistep deposition cycle. Films of AlN as thick as 4 lm are successfully integrated in RF silicon-on-glass bipolar junction transistors that display a reduction of more than 70% in the value of the thermal resistance
The reception and integration process of refugees and asylum seekers in Bizkaia: a reality with a variable geometry?
The processes of reception and integration are not only a complex and variable reality in the European Union but particularly in specific social contexts, such as cities and provinces. These must face the daily challenges of meeting the particular needs of refugees, ensuring daily coexistence. This paper presents the results of an interdisciplinary research on the degree of implementation of the reception and integration processes in Bizkaia, paying attention at the different phases of the Spanish Reception and Integration System for international protection applicants and beneficiaries. For that purpose, the capacity of recently launched programs, including the Goihabe Program, is analyzed in order to optimize the coordination and integral management of these processes in Bizkaia
Multiparametric study of the February-April 2013 paroxysmal phase of Mt. Etna New South-East crater
Between January 2011 and April 2013, Mt. Etna's eruptive activity consisted of episodic intracrater strombolian explosions and paroxysms from Bocca Nuova, Voragine, and the New South-East (NSEC) summit craters, respectively. Eruptions from NSEC consisted of initial increasing strombolian activity and lava flow output, passing to short-lasting lava fountaining. In this study we present seismic, infrasound, radiometric, plume SO2 and HCl fluxes and geodetic data collected by the INGV monitoring system between May 2012 and April 2013. The multiparametric approach enabled characterization of NSEC eruptive activity at both daily and monthly time scales and tracking of magma movement within Mt. Etna's plumbing system. While seismic, infrasound and radiometric signals give insight on the energy and features of the 13 paroxysms fed by NSEC, SO2 and halogen fluxes shed light on the likely mechanisms triggering the eruptive phenomena. GPS data provided clear evidence of pressurization of Mt. Etna's plumbing system from May 2012 to middle February 2013 and depressurization during the February-April 2013 eruptive activity. Taking into account geochemical data, we propose that the paroxysms' sequence represented the climax of a waxing-waning phase of degassing that had started as early as December 2012, and eventually ended in April 2013. Integration of the multidisciplinary observations suggests that the February-April 2013 eruptive activity reflects a phase of release of a volatile-rich batch of magma that had been stored in the shallow volcano plumbing system at least 4 months before, and with the majority of gas released between February and March 2013
Mirtazapine in the treatment of essential tremor: an open-label, observer-blind study
Essential tremor (ET) is the most common movement disorder in the adult population. At present ET treatment shows limited efficacy, particularly in patients with severe and disabling symptoms. This study evaluates the clinical efficacy of mirtazapine in an untreated ET patient population
An unloading foam model to constrain Etna’s 11–13 January 2011 lava fountaining episode
The 11–13 January 2011 eruptive episode at Etna volcano occurred after several months
of increasing ash emissions from the summit craters, and was heralded by increasing
SO2 output, which peaked at ∼5000 megagrams/day several hours before the start of the
eruptive activity. The eruptive episode began with a phase of Strombolian activity from a pit
crater on the eastern flank of the SE‐Crater. Explosions became more intense with time
and eventually became transitional between Strombolian and fountaining, before moving
into a lava fountaining phase. Fountaining was accompanied by lava output from the lower
rim of the pit crater. Emplacement of the resulting lava flow field, as well as associated lava
fountain‐ and Strombolian‐phases, was tracked using a remote sensing network comprising
both thermal and visible cameras. Thermal surveys completed once the eruptive episode
had ended also allowed us to reconstruct the emplacement of the lava flow field. Using a high
temporal resolution geostationary satellite data we were also able to construct a detailed
record of the heat flux during the fountain‐fed flow phase and its subsequent cooling. The
dense rock volume of erupted lava obtained from the satellite data was 1.2 × 106 m3; this
was emplaced over a period of about 6 h to give a mean output rate of ∼55 m3 s−1. By
comparison, geologic data allowed us to estimate dense rock volumes of ∼0.85 × 106 m3
for the pyroclastics erupted during the lava fountain phase, and 0.84–1.7 × 106 m3 for
lavas erupted during the effusive phase, resulting in a total erupted dense rock volume of
1.7–2.5 × 106 m3 and a mean output rate of 78–117 m3 s−1. The sequence of events and
quantitative results presented here shed light on the shallow feeding system of the volcano
Adhesion between oppositely-charged polyelectrolytes
The adhesion between a grafted polyelectrolyte layer (brush) and a gel of an oppositely charged polyelectrolyte has been measured as a function of applied pressure, and the interface has been traced using neutron reflectometry. The interface (in aqueous medium at pH 6) between the (polycationic) brush and the (polyanionic) gel has a limited pressure-dependence, with a small amount of deformation of the interface at the brush-gel contact. Brushes with a dry thickness of up to 13 nm exhibit weak adhesion (measured using a mechanical force tester) with an adhesive failure when the gel is detached. Thicker brushes result in the gel exhibiting cohesive failure. Reversing the geometry, whereby a polycationic brush is replaced with a polyanion and the polyanionic gel is replaced with a polycation reveals that the pH-dependence of the adhesion is moderately symmetric about pH 6, but that the maximum force required to separate the polycation gel from the polyanion brush over the range of pH is greater than that for the polycation brush and polyanion gel. The polyanion used is poly(methacrylic acid) (PMAA) and polycations of poly[2-(diethyl amino)ethyl methacrylate] (PDEAEMA) and poly[2-(dimethyl amino)ethyl methacrylate] (PDMAEMA) were used
Major eruptive style changes induced by structural modifications of a shallow conduit system: the 2007–2012 Stromboli case
Stromboli is known for its mild, persistent explosive
activity from the vents located within the summit crater
depression at the uppermost part of the Sciara del Fuoco (SdF)
depression. Effusive activity (lava flows) at this volcano normally
occurs every 5–15 years, involving often the opening of
eruptive fissures along the SdF, and more rarely overflows
from the summit crater. Between the end of the 2007 effusive
eruption and December 2012, the number of lava flows inside
and outside the crater depression has increased significantly,
reaching a total of 28, with an average of 4.8 episodes per year.
An open question is why this activity has become so frequent
during the last 6 years and was quite rare before. In this paper,
we describe this exceptional activity and propose an interpretation
based on the structural state of the volcano, changed
after the 2002–2003 and even more after the 2007 flank
effusive eruption. We use images from the Stromboli fixed
cameras network, as well as ground photos, plume SO2 and
CO2 fluxes released by the summit crater, and continuous
fumarole temperature recording, to unravel the interplay
between magma supply, structural and morphology
changes, and lava flow output. Our results might
help forecast the future behaviour and hazard at
Stromboli and might be applicable to other openconduit
volcanoes.partially supported by the Project
INGV-DPC Paroxysm V2/03, 2007–2009 funded by the Istituto
Nazionale di Geofisica e Vulcanologia and the Italian Civil ProtectionPublished8413V. Dinamiche e scenari eruttiviJCR Journalrestricte
High-density neutrophils in MGUS and multiple myeloma are dysfunctional and immune-suppressive due to increased STAT3 downstream signaling
To understand neutrophil impairment in the progression from MGUS through active MM, we investigated the function of mature, high-density neutrophils (HDNs), isolated from peripheral blood. In 7 MM, 3 MGUS and 3 healthy subjects by gene expression profile, we identified a total of 551 upregulated and 343 downregulated genes in MM-HDN, involved in chemokine signaling pathway and FC-gamma receptor mediated phagocytosis conveying in the activation of STAT proteins. In a series of 60 newly diagnosed MM and 30 MGUS patients, by flow-cytometry we found that HDN from MM, and to a lesser extend MGUS, had an up-regulation of the inducible FcγRI (also known as CD64) and a down-regulation of the constitutive FcγRIIIa (also known as CD16) together with a reduced phagocytic activity and oxidative burst, associated to increased immune-suppression that could be reverted by arginase inhibitors in co-culture with lymphocytes. In 43 consecutive newly-diagnosed MM patients, who received first-line treatment based on bortezomib, thalidomide and dexamethasone, high CD64 could identify at diagnosis patients with inferior median overall survival (39.5 versus 86.7 months, p = 0.04). Thus, HDNs are significantly different among healthy, MGUS and MM subjects. In both MGUS and MM neutrophils may play a role in supporting both the increased susceptibility to infection and the immunological dysfunction that leads to tumor progression
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Comorbid neuropathology and atypical presentation of Alzheimer's disease
IntroductionAlzheimer's disease (AD) neuropathological changes present with amnestic and nonamnestic (atypical) syndromes. The contribution of comorbid neuropathology as a substratum of atypical expression of AD remains under investigated.MethodsWe examined whether atypical AD exhibited increased comorbid neuropathology compared to typical AD and if such neuropathologies contributed to the accelerated clinical decline in atypical AD.ResultsWe examined 60 atypical and 101 typical AD clinicopathological cases. The number of comorbid pathologies was similar between the groups (p = 0.09). Argyrophilic grain disease was associated with atypical presentation (p = 0.008) after accounting for sex, age of onset, and disease duration. Vascular brain injury was more common in typical AD (p = 0.022). Atypical cases had a steeper Mini-Mental Status Examination (MMSE) decline over time (p = 0.033).DiscussionComorbid neuropathological changes are unlikely to contribute to atypical AD presentation and the steeper cognitive decline seen in this cohort.HighlightsAutopsy cohort of 60 atypical and 101 typical AD; does comorbid pathology explain atypical presentation?Atypical versus Typical AD: No significant differences in comorbid neuropathologies were found (p = 0.09).Argyrophilic Grain Disease Association: significantly correlates with atypical AD presentations, suggesting a unique neuropathological pattern (p = 0.008).Vascular Brain Injury Prevalence: Vascular brain injury is more common in typical AD than in atypical AD (p = 0.022).Cognitive Decline in Atypical AD: Atypical AD patients experience a steeper cognitive decline measured by MMSE than those with typical AD despite lacking more comorbid neuropathology, highlighting the severity of atypical AD pathogenesis (p = 0.033)
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