Land cover classification of Lago Grande de Curuai floodplain (Amazon, Brazil) using multi-sensor and image fusion techniques

Given the limitations of different types of remote sensing images, automated land-cover classifications of the Amazon várzea may yield poor accuracy indexes. One way to improve accuracy is through the combination of images from different sensors, by either image fusion or multi-sensor classifications. Therefore, the objective of this study was to determine which classification method is more efficient in improving land cover classification accuracies for the Amazon várzea and similar wetland environments - (a) synthetically fused optical and SAR images or (b) multi-sensor classification of paired SAR and optical images. Land cover classifications based on images from a single sensor (Landsat TM or Radarsat-2) are compared with multi-sensor and image fusion classifications. Object-based image analyses (OBIA) and the J.48 data-mining algorithm were used for automated classification, and classification accuracies were assessed using the kappa index of agreement and the recently proposed allocation and quantity disagreement measures. Overall, optical-based classifications had better accuracy than SAR-based classifications. Once both datasets were combined using the multi-sensor approach, there was a 2% decrease in allocation disagreement, as the method was able to overcome part of the limitations present in both images. Accuracy decreased when image fusion methods were used, however. We therefore concluded that the multi-sensor classification method is more appropriate for classifying land cover in the Amazon várzea.

Quantitative phenetics and taxonomy of some phlebotomine taxa

Elucidating the evolution of Phlebotominae is important not only to revise their taxonomy, but also to help understand the origin of the genus Leishmania and its relationship with humans. Our study is a phenetic portrayal of this history based on the genetic relationships among some New Word and Old Word taxa. We used both multilocus enzyme electrophoresis and morphometry on 24 male specimens of the Old Word genus Phlebotomus (with three of its subgenera: Phlebotomus, Spelaeophlebotomus and Australophlebotomus), and on 67 male specimens of the three New World genera, Warileya, Brumptomyia and Lutzomyia, (with three subgenera of Lutzomyia: Lutzomyia, Oligodontomyia and Psychodopygus). Phenetic trees derived from both techniques were similar, but disclosed relationships that disagree with the present classification of sand flies. The need for a true evolutionary approach is stressed.

Detection of beetle damage in forests by X-ray CT image processing

Some beetle species can have devastating economic impacts on forest and nursery industries. A recent example is Anophophora glabripennis, a species of beetle known in the United States as the ''Asian Longhorrned beetle'', which has damaged many American forests, and is a threat which can unintentionally reach south American countries, including Brazil. This work presents a new method based on X-ray computerized tomography (CT) and image processing for beetle injury detection in forests. Its results show a set of images with correct identification of the location of beetles in living trees as well as damage evaluation with time.

Fracture modes and acoustic emission characteristics of hydrogen-assisted cracking in high-strength low-alloy steel weldment

The aim of the present paper is to study the relationship between the fracture modes in hydrogen-assisted cracking (HAC) in microalloied steel and the emission of acoustic signals during the fracturing process. For this reason, a flux-cored arc weld (FCAW) was used in a high-strength low-alloy steel. The consumable used were the commercially available AWS E120T5-K4 and had a diameter of 1.6 mm. Two different shielding gases were used (CO2 and CO2+5% H2) to obtain complete phenomenon characterization. The implant test was applied with three levels of restriction stresses. An acoustic emission measurement system (AEMS) was coupled to the implant test apparatus. The output signal from the acoustic emission sensor was passed through an electronic amplifier and processed by a root mean square (RMS) voltage converter. Fracture surfaces were examined by scanning electron microscopy (SEM) and image analysis. Fracture modes were related with the intensity, the energy and the number of the peaks of the acoustic emission signal. The shielding gas CO2+5% H2 proved to be very useful in the experiments. Basically, three different fracture modes were identified in terms of fracture appearance: microvoid coalescence (MVC), intergranular (IG) and quasi-cleavage (QC). The results show that each mode of fracture presents a characteristic acoustic signal.

Chest magnetic resonance imaging: a protocol suggestion

Abstract In the recent years, with the development of ultrafast sequences, magnetic resonance imaging (MRI) has been established as a valuable diagnostic modality in body imaging. Because of improvements in speed and image quality, MRI is now ready for routine clinical use also in the study of pulmonary diseases. The main advantage of MRI of the lungs is its unique combination of morphological and functional assessment in a single imaging session. In this article, the authors review most technical aspects and suggest a protocol for performing chest MRI. The authors also describe the three major clinical indications for MRI of the lungs: staging of lung tumors; evaluation of pulmonary vascular diseases; and investigation of pulmonary abnormalities in patients who should not be exposed to radiation.

Pulmonary 64-MDCT angiography with 50 mL of iodinated contrast material in an unselected patient population: a feasible protocol

Abstract Objective: To propose a protocol for pulmonary angiography using 64-slice multidetector computed tomography (64-MDCT) with 50 mL of iodinated contrast material, in an unselected patient population, as well as to evaluate vascular enhancement and image quality. Materials and Methods: We evaluated 29 patients (22-86 years of age). The body mass index ranged from 19.0 kg/m2 to 41.8 kg/m2. Patients underwent pulmonary CT angiography in a 64-MDCT scanner, receiving 50 mL of iodinated contrast material via venous access at a rate of 4.5 mL/s. Bolus tracking was applied in the superior vena cava. Two experienced radiologists assessed image quality and vascular enhancement. Results: The mean density was 382 Hounsfield units (HU) for the pulmonary trunk; 379 and 377 HU for the right and left main pulmonary arteries, respectively; and 346 and 364 HU for the right and left inferior pulmonary arteries, respectively. In all patients, subsegmental arteries were analyzed. There were streak artifacts from contrast material in the superior vena cava in all patients. However, those artifacts did not impair the image analysis. Conclusion: Our findings suggest that pulmonary angiography using 64-MDCT with 50 mL of iodinated contrast can produce high quality images in unselected patient populations.

Pequisas físicas e químicas do sistema hidrográfico da região lagunar de Cananéia: I - Cursos de águas

The present elaboration is a "previous note" about two watercourses, Maria Rodrigues and Baguaçú, belonging to Hydrografic System of the Cananeas Lagoon Region in the Southern Part of it he Coast of the Estado de São Paulo, Brazil, which is the objete of our physical and chemical researches. It is based on the first results obtained from our contact with that region, ttfie studies of which are being continued and will still have to confirm or not the previous conclusions, which we are presenting in this "provisional paper". We studied the Maria Rodrigues and the Baguacu under the discussion whether they are to be clasified as a river in the poper sense ot the word or waUer-courses of any other origin. For this purpose we established observatory-stations along their whole course where we collected quantities of water to be analised. The data included in the table nº 1 and 2 refer to the physical and chemical properties of these portions of water. These physical and chemical properties were discussed and compared one with the other according to the observatory-stations, at the same moment and the tide predominating on that occasion. The physical and chemical datas were obtained according to the norms recommended by the Conseil International permanent pour l'Exploration de la Mer, Copenhague. We also presented a sketch of both; we described their relations with regard to the Mar de Cananéia; we inserted comprehensible histograms of the distribution of the observatory-stations, each of them with the respective indices, and at last we tried to correlate the occurrence of the "plancton" with the physical and chemical properties of water as well in the Maria Rodrigues as in the Baguacú. From these researches result the following previous conclusions: 1 - By the data obtained up to now nothing could be formulated as to a cyclical or "seasonal" aspect. 2 - By the comparison of the phenomena which present the rivers in the proper sense of the word and those observed in the Maria Rodrigues and the Baguacú, we are convinced that both are water-courses of the classical type "marigot,". 3 - Their channels are maintained open by the effect of the tide and, more perphaps, by the infiltration-water deriving from the underground-water level owing to the type of the soil of that region, which in mean shows an elevation of 2-4 meters over sea-level. 4 - From tables 1 and 2 and histograms 2 and 3 we stated that the water, not only of the Maria Rodrigues but also of the Baguacú, conserve more or less the same physical and chemical properties, provided that: 1) the localities to be compared are the mouths or equidistant points from them in the lower course, and 2) the moment and tide must be the same. Tables 3a and 3b show sufficiently this supposition.

Dos modelos de interpretación: la indeterminación de la traducción en quine y el argumento modelo teorético de Putnam

Las tesis de la indeterminación de Quine establecen que las condiciones de verdad de una oración sub-determinan la referencia de los términos que ocurren en la misma. La cuestión es ¿cuál es el alcance de esa sub-determinación? En Reason, Truth and History Putnam señala que la su-determinación es mayor de lo que podría suponerse a partir de los argumentos de Quine y se propone, con su "argumento modelo teorético", prolongar radicalmenteestos resultados. En este artículo pretendo mostrar que el argumento modelo teorético de Putnam no es una mera prolongación de los resultados de Quine, sino que se trata de un argumento que supone un modelo de interpretación distinto del que subyace al argumento de este último. Si estoy en lo cierto, tendríamos en este caso dos modos de entender la interpretación y dependerá de qué modo la entendamos, el alcance que le demos a la sub-determinación de la referencia por los valores veritativos. Considero, por lo tanto, que el argumento de Putnam, si bien radicaliza las conclusiones de Quine, lo hace introduciendo un modelo de interpretación diferente al que es desarrollado en Word and Object.

Tuberculose hepática pseudotumoral

Tuberculous involvement of the liver is usually a diffuse process, associated with miliary tuberculosis. However localized tuberculosis of the liver producing a macronodular tuberculoma or an abscess is rare. The authors present a case of pseudotumoral hepatic tuberculosis in a 34-year old woman. This patient presented a 2 month history of fever weight loss of 4Kg and right upper quadrant abdominal pain. She denied jaundice, choluria, or acholia. Laboratory investigation, including renal and liver function tests. revealed normal levels. Chest X-ray was normal. Abdominal ultrasonography demonstrated a hypoechoic nodule in the right hepatic lobe. CT scan showed hypodense areas in the same place and no retroperitoneal lymphadenopathy. Due to the inespecificity of the signs, symptoms and image findings, a diagnostic laparoscopy was performed, it was however inconclusive. Then, the patient was submitted to a laparotomy with ressection of the lesion. Histological examination revealed a tuberculoid granulomatous lesion with caseous necrosis. Postoperatively, the patient was placed on antituberculous chemotherapy with rifampin, isoniazid and pyrazinamide. Eight months later the patient is asymptomatic.

Pseudotumor pancreático

The decrease in morbidity and mortality of pancreaticoduodenectomy in reference centers has increased the incidence of benign histopathologic diagnosis in cases where a pre-operative diagnosis of pancreatic ductal carcinoma was expected (9,2%). Recent reports have shown that autoimune pancreatitis, an entity that can lead to a pathologic diagnosis of sclerosing lymphoplasmatic pancreatitis has been the cause of about 2,5% of wrong preoperative diagnosis. Clinical and image definitive diagnosis is still uncertain on those borderline cases. An increase in IgG4 has been reported as frequent in patients with autoimune pancreatitis which can respond to steroid treatment. In doubtful cases, four diagnosis can be expected: 1. Pancreatic ductal carcinoma; 2. Chronic alcoholic pancreatitis; 3. "Chronic pancreatitis secondary to choledocal lithiasis"; 4. Sclerosing lymphoplasmatic pancreatitis. Modern medical literature sugests that evaluation of IgG4 in doubtful cases of pancreatic tumor (pseudotumor of the pancreas) could avoid unnecessary pancreaticoduodenectomies in the future.

Experimental validation of a 3-D vision-based measurement system applied to robot calibration

One of the problems that slows the development of off-line programming is the low static and dynamic positioning accuracy of robots. Robot calibration improves the positioning accuracy and can also be used as a diagnostic tool in robot production and maintenance. A large number of robot measurement systems are now available commercially. Yet, there is a dearth of systems that are portable, accurate and low cost. In this work a measurement system that can fill this gap in local calibration is presented. The measurement system consists of a single CCD camera mounted on the robot tool flange with a wide angle lens, and uses space resection models to measure the end-effector pose relative to a world coordinate system, considering radial distortions. Scale factors and image center are obtained with innovative techniques, making use of a multiview approach. The target plate consists of a grid of white dots impressed on a black photographic paper, and mounted on the sides of a 90-degree angle plate. Results show that the achieved average accuracy varies from 0.2mm to 0.4mm, at distances from the target from 600mm to 1000mm respectively, with different camera orientations.

Não há dente de coelho no problema da tradução radical

O trabalho consiste em uma tentativa de refutação do princípio quineano da indeterminação da tradução radical. A estrutura do argumento é a seguinte. A demonstração do princípio no texto de Quine assenta-se sobre certa concepção do processo de tradução radical. Esta concepção só se sustenta se são adotadas certas pressuposições a respeito da natureza da linguagem e dos falantes. Entretanto, se estas pressuposições são adotadas, não há razão para não se aceitarem também outras pressuposições - as quais invalidam a demonstração de Quine.