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Synoptic preconditions for extreme flooding during the summer Asian Monsoon in the Mumbai area
The summer monsoon season is an important hydrometeorological feature of the Indian subcontinent and it has significant socioeconomic impacts. This study is aimed at understanding the processes associated with the occurrence of catastrophic flood events. The study has two novel features that add to the existing body of knowledge about the South Asian Monsoon: 1) combine traditional hydrometeorological observations (rain gauge measurements) with unconventional data (media and state historical records of reported flooding) to produce value-added century-long time-series of potential flood events, and 2) identify the larger regional synoptic conditions leading to days with flood potential in the time-series. The promise of mining unconventional data to extend hydrometeorological records is demonstrated in this study. The synoptic evolution of flooding events in the western-central coast of India and the densely populated Mumbai area are shown to correspond to active monsoon periods with embedded low-pressure centers and have far upstream influence from the western edge of the Indian Ocean basin. The coastal processes along the Arabian Peninsula where the currents interact with the continental shelf are found to be key features of extremes during the South Asian Monsoo
Introduction to the Special Issue on Natural Language and Learning Machines
1. Introduction The interaction between machine learning and natural language processing (NLP) research underlies most of the progress made in NLP for the last few decades (Cardie and Mooney 1999; Fung and Roth 2005). Machine Learning has been the common framework for the birth and development of most paradigms, discoveries and achievements in statistical natural language processing. At the international level the AAAI Fall symposiums in 1990 (Jacobs 1990) and 1992 (Goldman 1992) and the IBM ..
Evolved Galaxies at z > 1.5 from the Gemini Deep Deep Survey: The Formation Epoch of Massive Stellar Systems
We present spectroscopic evidence from the Gemini Deep Deep Survey (GDDS) for
a significant population of color-selected red galaxies at 1.3 < z < 2.2 whose
integrated light is dominated by evolved stars. Unlike radio-selected objects,
the z > 1.5 old galaxies have a sky density > 0.1 per sq. arcmin. Conservative
age estimates for 20 galaxies with z > 1.3; = 1.49, give a median age of
1.2 Gyr and = 2.4. One quarter of the galaxies have inferred z_f > 4.
Models restricted to abundances less than or equal to solar give median ages
and z_f of 2.3 Gyr and 3.3, respectively. These galaxies are among the most
massive and contribute approximately 50% of the stellar mass density at 1 < z <
2. The derived ages and most probable star formation histories suggest a high
star-formation-rate (300-500 solar masses per year) phase in the progenitor
population. We argue that most of the red galaxies are not descendants of the
typical z=3 Lyman break galaxies. Galaxies associated with luminous sub-mm
sources have the requisite star formation rates to be the progenitor
population. Our results point toward early and rapid formation for a
significant fraction of present day massive galaxies.Comment: 12 pages, 2 figures, 1 table, Accepted for publication, ApJ Letter
Cosmic Star Formation History and its Dependence on Galaxy Stellar Mass
We examine the cosmic star formation rate (SFR) and its dependence on galaxy
stellar mass over the redshift range 0.8 < z < 2 using data from the Gemini
Deep Deep Survey (GDDS). The SFR in the most massive galaxies (M > 10^{10.8}
M_sun) was six times higher at z = 2 than it is today. It drops steeply from z
= 2, reaching the present day value at z ~ 1. In contrast, the SFR density of
intermediate mass galaxies (10^{10.2} < M < 10^{10.8} M_sun) declines more
slowly and may peak or plateau at z ~ 1.5. We use the characteristic growth
time t_SFR = rho_M / rho_SFR to provide evidence of an associated transition in
massive galaxies from a burst to a quiescent star formation mode at z ~ 2.
Intermediate mass systems transit from burst to quiescent mode at z ~ 1, while
the lowest mass objects undergo bursts throughout our redshift range. Our
results show unambiguously that the formation era for galaxies was extended and
proceeded from high to low mass systems. The most massive galaxies formed most
of their stars in the first ~3 Gyr of cosmic history. Intermediate mass objects
continued to form their dominant stellar mass for an additional ~2 Gyr, while
the lowest mass systems have been forming over the whole cosmic epoch spanned
by the GDDS. This view of galaxy formation clearly supports `downsizing' in the
SFR where the most massive galaxies form first and galaxy formation proceeds
from larger to smaller mass scales.Comment: Accepted for publication in ApJ
Nutrition in chronic inflammatory conditions: Bypassing the mucosal block for micronutrients
Nutritional Immunity is one of the most ancient innate immune responses, during which the body can restrict nutrients availability to pathogens and restricts their uptake by the gut mucosa (mucosal block). Though this can be a beneficial strategy during infection, it also is associated with non‐communicable diseases—where the pathogen is missing; leading to increased morbidity and mortality as micronutritional uptake and distribution in the body is hindered. Here, we discuss the acute immune response in respect to nutrients, the opposing nutritional demands of regulatory and inflammatory cells and particularly focus on some nutrients linked with inflammation such as iron, vitamins A, Bs, C, and other antioxidants. We propose that while the absorption of certain micronutrients is hindered during inflammation, the dietary lymph path remains available. As such, several clinical trials investigated the role of the lymphatic system during protein absorption, following a ketogenic diet and an increased intake of antioxidants, vitamins, and minerals, in reducing inflammation and ameliorating disease
Gemini Deep Deep Survey VI: Massive Hdelta-strong galaxies at z=1
We show that there has been a dramatic decline in the abundance of massive
galaxies with strong Hdelta stellar absorption lines from z=1.2 to the present.
These ``Hdelta-strong'', or HDS, galaxies have undergone a recent and rapid
break in their star-formation activity. Combining data from the Gemini Deep
Deep and the Sloan Digital Sky Surveys to make mass-matched samples
(M*>=10^10.2 Msun), with 25 and 50,255 galaxies, respectively), we find that
the fraction of galaxies in an HDS phase has decreased from about 50% at z=1.2
to a few percent today. This decrease in fraction is due to an actual decrease
in the number density of massive HDS systems by a factor of 2-4, coupled with
an increase in the number density of massive galaxies by about 30 percent. We
show that this result depends only weakly on the threshold chosen for the
Hdelta equivalent width to define HDS systems (if greater than 4 A) and
corresponds to a (1+z)^{2.5\pm 0.7} evolution. Spectral synthesis studies of
the high-redshift population using the PEGASE code, treating Hdelta_A, EW[OII],
Dn4000, and rest-frame colors, favor models in which the Balmer absorption
features in massive Hdelta-strong systems are the echoes of intense episodes of
star-formation that faded about 1 Gyr prior to the epoch of observation. The
z=1.4-2 epoch appears to correspond to a time at which massive galaxies are in
transition from a mode of sustained star formation to a relatively quiescent
mode with weak and rare star-formation episodes. We argue that the most likely
local descendants of the distant massive HDS galaxies are passively evolving
massive galaxies in the field and small groups.Comment: 16 pages, 12 figures, 3 tables, uses emulateapj.sty; updated to match
the version accepted by ApJ. One figure added, conclusions unchange
Re: Adjuvant Treatment of High-Risk, Radically Resected Gastric Cancer Patients with 5-Fluorouracil, Leucovorin, Cisplatin, and Epidoxorubicin in a Randomized Controlled Trial
Corruption et investissement externe direct au Brésil
O Brasil até 2010 ficou entre os 10 principais países receptores de IED, mas de 2010 a 2014, perdeu posições no ranking dos países receptores de IED. Um dos fatores econômicos que os investidores analisam na escolha do país receptor é a corrupção, que é um dos principais desafios enfrentados pelo Brasil. O presente trabalho tem como objetivo analisar a percepção de executivos de empresas multinacionais sobre o quanto a corrupção influenciou no IED do Brasil no período de 2010 a 2014. Para tanto, utilizou-se uma metodologia de pesquisa em duas partes complementares. Na primeira foram realizadas entrevistas com dois executivos de multinacionais de capital estrangeiro. Na segunda foram enviados questionários para multinacionais de capital estrangeiro atuantes no Brasil. Após a análise dos dados coletados de ambas as pesquisas percebeu-se que a corrupção é um fator condicionante para a entrada de IED no país e que o Brasil precisa combater e controlar a corrupção, pois a mesma afeta a qualidade dos serviços prestados, a infraestrutura e o investimento global no país
Dyspnea perception during the inspiratory resistive loads test in obese subjects waiting bariatric surgery
Identifcation of low dyspnea perception is relevant, since this condition is signifcantly associated with worse outcomes. We investigated dyspnea perception during the inspiratory resistive loads test on obese subjects waiting bariatric surgery in comparison with normal subjects. Secondarily, we analysed the proportion of obese subjects with low, moderate and high dyspnea perception. This observational study included subjects with body mass index (BMI)≥35kg/m2, compared to healthy subjects with BMI ≥18 and <25kg/m2. Subject underwent clinical evaluation, inspiratory test with progressive resistive loads and spirometry. We studied 23 obese subjects (mean BMI=51.9±9.3kg/ m2) and 25 normal subjects (mean BMI=24.3±2.3kg/m2). With the increase magnitude of resistive loads there was a signifcant increase in dyspnea score (p<0.001) and progressive increase of the generated inspiratory pressure (p<0.001), but there was no diference between the groups in terms of dyspnea score (p=0.191) and no interaction efect (p=0.372). Among the obese subjects, 4 individuals were classifed as low perception, 11 as moderate and 8 as high. In conclusion, the degree of dyspnea perception during the inspiratory progressive resistive loads test did not difer between obese and normal subjects. Among obese subjects, only 17% were classifed as low dyspnea perception
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