180 research outputs found
A network model for field and quenched disorder effects in artificial spin ice
We have performed a systematic study of the effects of field strength and
quenched disorder on the driven dynamics of square artificial spin ice. We
construct a network representation of the configurational phase space, where
nodes represent the microscopic configurations and a directed link between node
i and node j means that the field may induce a transition between the
corresponding configurations. In this way, we are able to quantitatively
describe how the field and the disorder affect the connectedness of states and
the reversibility of dynamics. In particular, we have shown that for optimal
field strengths, a substantial fraction of all states can be accessed using
external driving fields, and this fraction is increased by disorder. We discuss
how this relates to control and potential information storage applications for
artificial spin ices
Surface albedo changes with time on Titan’s possible cryovolcanic sites: Cassini/VIMS processing and geophysical implications
We present a study on Titan’s possibly cryovolcanic and varying regions as suggested from previous studies [e.g. 1;2;7]. These regions, which are potentially subject to change over time in brightness and are located close to the equator, are Tui Regio, Hotei Regio, and Sotra Patera. We apply two methods on Cassini/VIMS data in order to retrieve their surface properties and monitor any temporal variations. First, we apply a statistical method, the Principal Component Analysis (PCA) [3;4] where we manage to isolate regions of distinct and diverse chemical composition called ‘Region of interest – RoI’. Then, we focus on retrieving the spectral differences (with respect to the Huygens landing site albedo) among the RoIs by applying a radiative transfer code (RT) [5;3]. Hence, we are able to view the dynamical range and evaluate the differences in surface albedo within the RoIs of the three regions. In addition, using this double procedure, we study the temporal surface variations of the three regions witnessing albedo changes with time for Tui Regio from 2005-2009 (darkening) and Sotra Patera from 2005-2006 (brightening) at all wavelengths [3]. The surface albedo variations and the presence of volcanic-like features within the regions in addition to a recent study [6] that calculates Titan's tidal response are significant indications for the connection of the interior with the cryovolcanic candidate features with implications for the satellite’s astrobiological potential
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Intracranial and subcortical volumes in adolescents with early‐onset psychosis: A multisite mega‐analysis from the ENIGMA consortium
Early‐onset psychosis disorders are serious mental disorders arising before the age of 18 years. Here, we investigate the largest neuroimaging dataset, to date, of patients with early‐onset psychosis and healthy controls for differences in intracranial and subcortical brain volumes. The sample included 263 patients with early‐onset psychosis (mean age: 16.4 ± 1.4 years, mean illness duration: 1.5 ± 1.4 years, 39.2% female) and 359 healthy controls (mean age: 15.9 ± 1.7 years, 45.4% female) with magnetic resonance imaging data, pooled from 11 clinical cohorts. Patients were diagnosed with early‐onset schizophrenia (n = 183), affective psychosis (n = 39), or other psychotic disorders (n = 41). We used linear mixed‐effects models to investigate differences in intracranial and subcortical volumes across the patient sample, diagnostic subgroup and antipsychotic medication, relative to controls. We observed significantly lower intracranial (Cohen's d = −0.39) and hippocampal (d = −0.25) volumes, and higher caudate (d = 0.25) and pallidum (d = 0.24) volumes in patients relative to controls. Intracranial volume was lower in both early‐onset schizophrenia (d = −0.34) and affective psychosis (d = −0.42), and early‐onset schizophrenia showed lower hippocampal (d = −0.24) and higher pallidum (d = 0.29) volumes. Patients who were currently treated with antipsychotic medication (n = 193) had significantly lower intracranial volume (d = −0.42). The findings demonstrate a similar pattern of brain alterations in early‐onset psychosis as previously reported in adult psychosis, but with notably low intracranial volume. The low intracranial volume suggests disrupted neurodevelopment in adolescent early‐onset psychosis
The March 11th, 2011, M 9.0 earthquake offshore Honshu island (Japan): a synthesis of the Tohoku-Oki INGV Team research activities
On March 11th, 2011 (at 05:46:23 UTC) a megaearthquake (M 9.0) occurred near the NE coast of Honshu
island ( Japan), originated near the subduction plate boundary between the Pacific and the North America
plates. The epicenter has been located at about 130 km East of Sendai city, at a depth of about 32 km. This
seismic event has been followed by a devastating tsunami. The location, the geometric parameters, the focal
mechanism, are in agreement with the occurrence of the earthquake along the subduction plate boundary. The
initial seismological analysis indicated that a surface of about 300 km x 150 km over the fault moved upwards of
30-40 m. The Tohoku-Oki INGV Team has made available a wide and multisciplinary expertise to investigate the
different scientific issues concerning the earthquake. Indeed from Seismology to Geomorphology, from Remote
Sensing to GPS, from Tsunami to Source Modeling the INGV Team has completed a wide range of analysis,
obtaining relevant outcomes that are summarized in this work.Published1-272T. Tettonica attivaN/A or not JCRope
The March 11th, 2011, M 9.0 earthquake offshore Honshu island (Japan): a synthesis of the Tohoku-Oki INGV Team research activities
On March 11th, 2011 (at 05:46:23 UTC) a megaearthquake (M 9.0) occurred near the NE coast of Honshu
island ( Japan), originated near the subduction plate boundary between the Pacific and the North America
plates. The epicenter has been located at about 130 km East of Sendai city, at a depth of about 32 km. This
seismic event has been followed by a devastating tsunami. The location, the geometric parameters, the focal
mechanism, are in agreement with the occurrence of the earthquake along the subduction plate boundary. The
initial seismological analysis indicated that a surface of about 300 km x 150 km over the fault moved upwards of
30-40 m. The Tohoku-Oki INGV Team has made available a wide and multisciplinary expertise to investigate the
different scientific issues concerning the earthquake. Indeed from Seismology to Geomorphology, from Remote
Sensing to GPS, from Tsunami to Source Modeling the INGV Team has completed a wide range of analysis,
obtaining relevant outcomes that are summarized in this work
Drucker\u27s Insights on Market Orientation and Innovation: Implications for Emerging Areas in High-Technology Marketing
In 1954, Drucker boldly declared that organizations have only two basic functions, marketing and innovation. While true for any organization, this insight is particularly pertinent for technology-based businesses. The complicated environment surrounding high-tech companies creates a great need for sophisticated marketing, yet these companies continue to have under-developed competencies in marketing and in understanding customer needs. In its first two sections, this essay explores Drucker’s insights with respect to two particularly salient issues for high-tech companies: developing and implementing a market orientation, and sustained break-through innovations. We review Drucker’s insights and synthesize them with the scholarly research on these issues. In the third section, we discuss three emerging areas in high-tech marketing where academics and managers could build on Drucker’s insight to guide future research and practice: market-driving, customer co-creation, and corporate social responsibility. The illustrative examples provided by these emerging areas highlight that even today, Drucker’s writings continue to offer remarkable guidance to scholars and managers who are willing to take the time to reflect, understand, and incorporate these insights in the unique context of high-tech industries
Phase 1 dose-finding and pharmacokinetic study of eribulin-liposomal formulation in patients with solid tumours
Background:
This phase 1 study examined the safety, tolerability, pharmacokinetics and preliminary efficacy of eribulin-liposomal formulation (eribulin-LF) in patients with advanced solid tumours.
Methods:\ud
Eligible patients with ECOG PS 0–1 were treated with eribulin-LF either on day 1 every 21 days (Schedule 1), or on days 1 and 15 every 28 days (Schedule 2). Doses ranged from 1.0 to 3.5 mg/m2, with dose escalation in a 3 + 3 design. The dose-expansion phase evaluated eribulin-LF in select tumour types. Primary objectives: maximum tolerated dose (MTD) and the recommended dose/schedule of eribulin-LF.
Results:
Totally, 58 patients were enroled (median age = 62 years). The MTD was 1.4 mg/m2 (Schedule 1) or 1.5 mg/m2 (Schedule 2), the latter dose selected for the dose-expansion phase. Dose-limiting toxicity (DLTs) in Schedule 1: hypophosphatemia and increased transaminase levels. DLTs in Schedule 2: stomatitis, increased alanine aminotransferase, neutropenia and febrile neutropenia. The pharmacokinetic profile of eribulin-LF showed a similar half-life to that of eribulin (~30 h), but with a 5-fold greater maximum serum concentration and a 40-fold greater area-under-the-curve. Eribulin-LF demonstrated clinical activity with approximately 10% of patients in both schedules achieving partial responses.
Conclusions:
Eribulin-LF was well tolerated with a favourable pharmacokinetic profile. Preliminary evidence of clinical activity in solid tumours was observed
Complementarities between IT and Organizational Structure: The Role of Corporate Exploration and Exploitation
The decentralization of organizational decision authority has been shown to be complementary to Information Technology (IT) in prior research. We draw from the information processing view of organizations, the IT and de/centralization debate, and organizational learning theory to argue that IT payoffs can also be improved by greater centralization of decision authority, contingent on a firm’s corporate learning type. We argue that an exploratory learning type is best pursued with a decentralized organization design, while an exploitative learning type requires a centralized organization design. We hypothesize that under corporate exploration, IT payoffs are enhanced through greater decentralization, whereas under corporate exploitation, returns to IT are improved by greater centralization. Our study uses a novel multi‐source panel on the IT capital, the degree of de/centralization, and the performance of almost 260 German manufacturing firms. We estimate production functions to assess the contribution of combning IT with de/centralization to firmlevel productivity under different corporate learning types. Our results strongly support our hypotheses and hold up to a variety of robustness tests
Widespread white matter microstructural differences in schizophrenia across 4322 individuals:Results from the ENIGMA Schizophrenia DTI Working Group
The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.Molecular Psychiatry advance online publication, 17 October 2017; doi:10.1038/mp.2017.170
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