Quantum optical coherence tomography with dispersion cancellation

We propose a new technique, called quantum optical coherence tomography (QOCT), for carrying out tomographic measurements with dispersion-cancelled resolution. The technique can also be used to extract the frequency-dependent refractive index of the medium. QOCT makes use of a two-photon interferometer in which a swept delay permits a coincidence interferogram to be traced. The technique bears a resemblance to classical optical coherence tomography (OCT). However, it makes use of a nonclassical entangled twin-photon light source that permits measurements to be made at depths greater than those accessible via OCT, which suffers from the deleterious effects of sample dispersion. Aside from the dispersion cancellation, QOCT offers higher sensitivity than OCT as well as an enhancement of resolution by a factor of 2 for the same source bandwidth. QOCT and OCT are compared using an idealized sample.Comment: 19 pages, 4 figure

Chiral symmetry restoration and the Z3 sectors of QCD

Quenched SU(3) lattice gauge theory shows three phase transitions, namely the chiral, the deconfinement and the Z3 phase transition. Knowing whether or not the chiral and the deconfinement phase transition occur at the same temperature for all Z3 sectors could be crucial to understand the underlying microscopic dynamics. We use the existence of a gap in the Dirac spectrum as an order parameter for the restoration of chiral symmetry. We find that the spectral gap opens up at the same critical temperature in all Z3 sectors in contrast to earlier claims in the literature.Comment: 4 pages, 4 figure

Natural history of \u3ci\u3eCassida sphaerula\u3c/i\u3e Boheman, 1854 (Coleoptera: Chrysomelidae: Cassidinae: Cassidini) on \u3ci\u3eArctotheca prostrata\u3c/i\u3e (Salisb.) Britten (Asteraceae: Arctotidinae) in South Africa, with a checklist of South African Cassidinae (leaf-mining and tortoise beetles)

The tortoise beetle, Cassida sphaerula Boheman, 1854 (Coleoptera: Chrysomelidae: Cassidinae: Cassidini) is endemic to South Africa. Its endemic host, Arctotheca prostrata (Salisb.) Britten (Asteraceae) has been introduced in other countries where it is becoming invasive. Cassida sphaerula could provide a potential biocontrol of Arctotheca weeds as it spends the entire life cycle on this host. An intensive field study, with rearing, photography, and short films of C. sphaerula was conducted in its native habitat to document the life cycle. A checklist of Cassidinae genera in South Africa, along with 19 new host records for Cassidini species in South Africa are presented. Oothecae are simple, with few laminate membranes enclosing fewer than five eggs. There are five larval instars. Larvae and adults feed by making a series of cuts in the ventral cuticle, forming an arc, and they consume the mesophyll as the cuticle is rolled to one side. This creates many ventral craters, thickened on one margin with the rolled cuticle; these ventral craters correspond to ‘windows’ in the dorsal leaf surface where the dorsal cuticle is left intact. This unusual feeding pattern is known in three Cas­sida species, all in South Africa. Like many tortoise beetles, instar I initiates a feces-only shield on its paired caudal processes (= urogomophi); this construction is retained, along with exuviae, by subsequent instars. The shield construction was studied by film and dissections. This revealed that the columnar or pyramidal shield in this species has an exterior of dry or moist feces that obscures the central nested stack of exuviae, each exuviae compressed onto the caudal processes. Pupae may retain the entire larval shield of exuviae and feces or only the 5th instar exuviae; this behavioral flexibility in pupal shield retention is novel for tortoise beetles. Behaviors of C. sphaerula are discussed in the context of phylogenetic characters that can give evolu­tionary insights into the genus, tribe, and subfamily

Humeral chondrosarcoma associated with lung metastases in a young dog - case report

ABSTRACT Chondrosarcoma, an unusual malignant neoplasm, develops in cartilaginous tissue and presents low rate of metastasis, mainly affecting the axial skeleton from the adult to senile dogs. In the face of unusual occurrence of chondrosarcoma in the long bones of young dogs, the present report aimed to describe it in the right humerus of a two-and-a-half-year-old Siberian Husky, attended at the Veterinary Hospital of the University of Franca, with limping of the right thoracic limb, for 20 days. The radiographic examination of the humerus showed bone lysis and periosteal proliferation. In the incisional biopsy, proliferation of atypical chondrocytes with diffuse distribution, interspersed with compact bone matrix, was observed. The amputation of the limb was performed, and the fragment histopathological analysis showed grade I chondrosarcoma. Periodic returns were made for neoplastic staging, and at 240 days after surgery lung metastases were detected, however, the tutor did not authorize chemotherapy and radiotherapy for financial reasons and due to the absence of respiratory symptoms so far (410 days after surgery). Although uncommon, chondrosarcoma can affect the long bones of young dogs, with clinical signs similar to other bone neoplasms, and, even with the radical limb amputation, can demonstrate systemic metastasis

The fraction of cancer attributable to ways of life, infections, occupation, and environmental agents in Brazil in 2020

Many human cancers develop as a result of exposure to risk factors related to the environment and ways of life. The aim of this study was to estimate attributable fractions of 25 types of cancers resulting from exposure to modifiable risk factors in Brazil. The prevalence of exposure to selected risk factors among adults was obtained from population-based surveys conducted from 2000 to 2008. Risk estimates were based on data drawn from metaanalyses or large, high quality studies. Population-attributable fractions (PAF) for a combination of risk factors, as well as the number of preventable deaths and cancer cases, were calculated for 2020. The known preventable risk factors studied will account for 34% of cancer cases among men and 35% among women in 2020, and for 46% and 39% deaths, respectively. The highest attributable fractions were estimated for tobacco smoking, infections, low consumption of fruits and vegetables, excess weight, reproductive factors, and physical inactivity. This is the first study to systematically estimate the fraction of cancer attributable to potentially modifiable risk factors in Brazil. Strategies for primary prevention of tobacco smoking and control of infection and the promotion of a healthy diet and physical activity should be the main priorities in policies for cancer prevention in the country. \ua9 2016 Azevedo e Silva et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Caracterização de terras pretas arqueológicas no sul do estado do Amazonas

The Archaeological Dark Earth (ADE) soils are characterized by its high fertility, dark color, and presence of pottery fragments. Regarding the formation of ADE, the most widely accepted hypothesis is that anthropogenic processes involving pre-Columbian populations made them. The purpose of this study is to characterize ADE units located in the Southern Amazon Region, in the cities of Apuí and Manicoré. Seven ADE sites were selected, trenches opened and the soil profiles characterized morphologically. Then, samples of each horizon were collected for analyses of the following physical and chemical properties: particle size, water-dispersible clay, flocculation, soil bulk density, particle density, total porosity, pH in water and KCl solutions, Ca2+, Mg2+, K+, Al3+, available P, H+Al, and organic C. Also, total oxides, free oxides and amorphous forms were analyzed. The texture of the anthropic A horizon ranged from sandy loam to clay loam. The pottery fragments and lithic material were found in similar quantities and at similar depths in the A horizons of the studied soil profiles, suggesting some similarity between the anthropogenic factors of formation. The anthropic horizons of profiles P3, P4, and P7 had a eutrophic character and high to very high levels of available phosphorus, compared to P1, P2, P5, and P6, indicating the heterogeneity of the ADEs.Departamento de Agronomia: Ciência do Solo UFRPE, Rua Dom Manoel, s/n, CEP 52171-900 Recife PEInstituto de Educação, Agricultura e Ambiente UFAM, Rua 29 de Agosto, 786, Centro, CEP 69.800-000 Humaitá AMUNESP, Via de Acesso Prof. Paulo Donato Castellane, CEP 14870-900, Jaboticabal, SPUFAM, Avenida General Rodrigo Oct Jor Ra, 3000, Cam Univ, Cor I, CEP 69077-000 Manaus AMDep. de Solos e Adubos FCAV/UNESP, Via de Acesso Prof. Paulo Donato Castellane, CEP 14870-900 Jaboticabal SPFCAV/UNESPUNESP, Via de Acesso Prof. Paulo Donato Castellane, CEP 14870-900, Jaboticabal, SPDep. de Solos e Adubos FCAV/UNESP, Via de Acesso Prof. Paulo Donato Castellane, CEP 14870-900 Jaboticabal SPFCAV/UNES

MÉTODOS PARA ESTIMAR O VOLUME DE FUSTES E GALHOS NA FLORESTA NACIONAL DO TAPAJÓS1

RESUMO Objetivou-se aplicar e avaliar métodos para estimar múltiplos volumes em uma Área de Manejo Comunitário, localizada na Floresta Nacional do Tapajós. Foram cubadas, rigorosamente, 516 árvores-amostra de 21 espécies comerciais, todas com 50 cm > dap < 160 cm. Utilizaram-se o modelo único para múltiplos volumes (análise de regressão) proposto por Leite et al. (1995) e redes neurais artificiais (RNA) para a estimativa do volume de fuste e galhos. Após os resultados preliminares usando o método de regressão, optou-se por separar os dados em três estratos, considerando a relação volume de galhos em razão do volume de fuste comercial. As equações geradas por estratos apresentaram melhoria nos ajustes, mas os resultados obtidos pela RNA foram melhores que os pelas equações de regressão