37 research outputs found
COMPILATION OF ACTIVE FAULT DATA IN PORTUGAL FOR USE IN SEISMIC HAZARD ANALYSIS
To estimate where future earthquakes are likely to occur, it is essential to combine information about past earthquakes with knowledge about the location and seismogenic properties of active faults. For this reason, robust probabilistic seismic hazard analysis (PSHA) integrates seismicity and active fault data. Existing seismic hazard assessments for Portugal rely exclusively on seismicity data and do not incorporate data on active faults. Project SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded initiative (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are developing a fully-parameterized active fault database for Portugal that incorporates existing compilations, updated according to the most recent publications. The seismogenic source model derived for SHARE will be the first model for Portugal to include fault data and follow an internationally standardized approach. This model can be used to improve both seismic hazard and risk analyses and will be combined with the Spanish database for use in Iberian- and European-scale assessments
Magnetic detection of sentinel lymph node in papillary thyroid carcinoma: The MAGIC-PAT study results
Introduction: Despite the controversy concerning sentinel lymph node biopsy (SLNB) in papillary thyroid carcinoma (PTC), successful detection rates can be achieved by radioguidance and vital dyeing. However, the drawbacks in both techniques are notable. Magnetic-guided SLNB (mSLNB) using superparamagnetic iron oxide (SPIO) nanoparticles is appealing as an alternative procedure.
Materials and Methods: mSLNB using the Sentimag-Sienna System ® , total thyroidectomy and central compartment dissection (CCD) were performed on all PTC patients. Lymph node involvement was assessed by postoperative pathological examination.
Results: From 2014 to 2016, 33 consecutive patients with PTC were enrolled in the study. A total of 20 patients met the eligibility. mSLNB succeeded in 16 patients, with a detection rate of 80%. A median of two SLN per patient were detected. A median of 10.5 non-sentinel lymph nodes (NSLN) from CCD were examined. Among the patients, 56.25% (9/16) had no metastatic nodes, while 12.5% (2/16) had exclusively SLN involvement. No false negative cases were found. The agreement between SLN and NSLN status was 87.5%. The prediction of NSLN involvement by SLN status showed 100% sensitivity, 81.8% specificity, 71.4% PPV and 100% NPV. Subsequently, mSLNB and the final pathological analysis would discriminate 43.75% (7/16) of patients who would certainly benefit from CCD whilst 56.25% of the total would confirm an unnecessary lymphadenectomy and avoid morbidity.
Conclusion: mSLNB showed satisfactory performance in PTC with clinical-negative nodes. We have shown mSLNB to be a good predictor of central compartment status that can improve the staging and management of PTC patients
Loop-Generated Bounds on Changes to the Graviton Dispersion Relation
We identify the effective theory appropriate to the propagation of massless
bulk fields in brane-world scenarios, to show that the dominant low-energy
effect of asymmetric warping in the bulk is to modify the dispersion relation
of the effective 4-dimensional modes. We show how such changes to the graviton
dispersion relation may be bounded through the effects they imply, through
loops, for the propagation of standard model particles. We compute these bounds
and show that they provide, in some cases, the strongest constraints on
nonstandard gravitational dispersions. The bounds obtained in this way are the
strongest for the fewest extra dimensions and when the extra-dimensional Planck
mass is the smallest. Although the best bounds come for warped 5-D scenarios,
for which the 5D Planck Mass is O(TeV), even in 4 dimensions the graviton loop
can lead to a bound on the graviton speed which is comparable with other
constraints.Comment: 18 pages, LaTeX, 4 figures, uses revte
Plant stature heritability in wheat: estimate through the regression coefficient
O estudo desenvolvido neste trabalho foi estabelecido para determinar a relação entre o desempenho do caráter estatura de planta, entre linhas F3 ou F4 ou RC1 F2, derivadas de F2 ou F3 ou RC1 F1, de diversos cruzamentos de trigo hexaplóide. Resultados superiores à unidade, para a herdabilidade, foram estimados através dó método de desvio padrão, calculando-se a regressão pela codificação dos dados originais, em termos de unidades de desvio padrão. Uma comparação entre o método convencional e o de unidades de desvio padrão foi realizada para as estimativas de herdabilidade. Em programas de melhoramento fitogenético, muitas questões poderão ser respondidas através da estimativa da herdabilidade de um determinado caráter. The study reported herein was designed to determine the relationship between the plant stature trait performance of F3 or F4 or RC1 F2 derived lines from F2 or F3 or RC1 F1 in several hexaploid wheat crosses, respectively. The heritability results greater than one were computed through the standard unit method by calculating the regression on data coded in terms of standard deviation units. A comparison was made between heritability estimated by these two methods, conventional and standard units. Heritability estimates provides useful guidelines of answering many questions which arise in a plant breeding program
Compilation of parameterized seismogenic sources in Iberia for the SHARE European-scale seismic source model.
Abstract: SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded project (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are compiling a fully-parameterized active fault database for Iberia and the nearby offshore region. The principal goal of this initiative is for fault sources in the Iberian region to be represented in SHARE and incorporated into the source model that will be used to produce seismic hazard maps at the European scale. The SHARE project relies heavily on input from many regional experts throughout the Euro-Mediterranean region. At the SHARE regional meeting for Iberia, the 2010 Working Group on Iberian Seismogenic Sources (WGISS) was established; these researchers are contributing to this large effort by providing their data to the Iberian regional integrators in a standardized format. The development of the SHARE Iberian active fault database is occurring in parallel with IBERFAULT, another ongoing effort to compile a database of active faults in the Iberian region.
The SHARE Iberian active fault database synthesizes a wide range of geological and geophysical observations on active seismogenic sources, and incorporates existing compilations (e.g., Cabral, 1995; Silva et al., 2008), original data contributed directly from researchers, data compiled from the literature, parameters estimated using empirical and analytical relationships, and, where necessary, parameters derived using expert judgment. The Iberian seismogenic source model derived for SHARE will be the first regional-scale source model for Iberia that includes fault data and follows an internationally standardized approach (Basili et al., 2008; 2009). This model can be used in both seismic hazard and risk analyses and will be appropriate for use in Iberian- and European-scale assessments
First attempt at measuring the CMB cross-polarization
We compute upper limits on CMB cross-polarization by cross-correlating the
PIQUE and Saskatoon experiments. We also discuss theoretical and practical
issues relevant to measuring cross-polarization and illustrate them with
simulations of the upcoming BOOMERanG 2002 experiment. We present a method that
separates all six polarization power spectra (TT, EE, BB, TE, TB, EB) without
any other "leakage" than the familiar EE-BB mixing caused by incomplete sky
coverage. Since E and B get mixed, one might expect leakage between TE and TB,
between EE and EB and between BB and EB - our method eliminates this by
preserving the parity symmetry under which TB and EB are odd and the other four
power spectra are even.Comment: Polarization movies can be found at
http://www.hep.upenn.edu/~angelica/polarization.htm
Climate change facilitated the early colonization of the Azores Archipelago during medieval times
Humans have made such dramatic and permanent changes to Earth's landscapes that much of it is now substantially and irreversibly altered from its preanthropogenic state. Remote islands, until recently isolated from humans, offer insights into how these landscapes evolved in response to human-induced perturbations. However, little is known about when and how remote systems were colonized because archaeological data and historical records are scarce and incomplete. Here, we use a multiproxy approach to reconstruct the initial colonization and subsequent environmental impacts on the Azores Archipelago. Our reconstructions provide unambiguous evidence for widespread human disturbance of this archipelago starting between 700 -60/+50 and 850 -60/+60 Common Era (CE), ca. 700 y earlier than historical records suggest the onset of Portuguese settlement of the islands. Settlement proceeded in three phases, during which human pressure on the terrestrial and aquatic ecosystems grew steadily (i.e., through livestock introductions, logging, and fire), resulting in irreversible changes. Our climate models suggest that the initial colonization at the end of the early Middle Ages (500 to 900 CE) occurred in conjunction with anomalous northeasterly winds and warmer Northern Hemisphere temperatures. These climate conditions likelyinhibited exploration from southern Europe and facilitated human settlers from the northeast Atlantic. These results are consistent with recent archaeological and genetic data suggesting that the Norse were most likely the earliest settlers on the islands