Towards high-resolution shell midden archaeology: Experimental and ethnoarchaeology in Tierra del Fuego (Argentina)

This paper discusses the ongoing ethnoarchaeological research carried out in Yamana shell middens of Tierra del Fuego. Ethnoarchaeology is used in this research as a tool to improve the archaeological methodology by testing it against anthropological, ethnographical and ethnological sources for achieving more accurate reconstructions of past societies. The ethnographical/ethnological information also is coupled with an experimental approach devised to understand physical and social processes, such as site formation processes and resource use and management. Specifically, this experimental approach was applied to the archaeological sites Tunel VII and Lanashuaia I (Tierra del Fuego, Argentina). (C) 2011 Elsevier Ltd and INQUA. All rights reserved.

A compact and high-resolution version of a capacitively coupled contactless conductivity detector

An all-in-one version of a capacitively coupled contactless conductivity detector is introduced. The absence of moving parts (potentiometers and connectors) makes it compact (6.5 cm(3)) and robust. A local oscillator, working at 1.1 MHz, was optimized to use capillaries of id from 20 to 100 lam. Low noise circuitry and a high-resolution analog-to-digital converter (ADC) (21 bits effective) grant good sensitivities for capillaries and background electrolytes currently used in capillary electrophoresis. The fixed frequency and amplitude of the signal generator is a drawback that is compensated by the steady calibration curves for conductivity. Another advantage is the possibility of determining the inner diameter of a capillary by reading the ADC when air and subsequently water flow through the capillary. The difference of ADC reading may be converted into the inner diameter by a calibration curve. This feature is granted by the 21-bit ADC, which eliminates the necessity of baseline compensation by hardware. In a typical application, the limits of detection based on the 3 sigma criterion (without baseline filtering) were 0.6, 0.4, 0.3, 0.5, 0.6, and 0.8 mu mol/L for K(+), Ba(2+), Ca(2+), Na(+), Mg(2+), and Li(+), respectively, which is comparable to other high-quality implementations of a capacitively coupled contactless conductivity detector.

Identification of new isolates of Bacillus thuringiensis using rep-PCR products and delta-endotoxin electron microscopy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

High-resolution electrocardiography in dogs under doxorubicin-induced cardiomyopathy

Determinaram-se a ocorrência de potencial tardio em cães com cardiomiopatia induzida pela doxorrubicina e sua relação com o desenvolvimento de arritmias ventriculares ou morte súbita. Sete cães adultos, sem raça definida, de ambos os sexos foram utilizados. A cardiomiopatia foi induzida por infusão venosa lenta de doxorrubicina (30mg/m²) em intervalos de 21 dias, até uma dose total cumulativa de 240mg/m². Os animais foram monitorados ecocardiograficamente. Após a confirmação da cardiomiopatia, foi feito o registro da eletrocardiografia de alta resolução. Potenciais tardios foram observados em dois animais que morreram subitamente poucos dias após.

High-resolution electrocardiography in the diagnosis of arrhythmogenic right ventricular cardiomyopathy in Boxer dogs

Com o objetivo de avaliar a importância da eletrocardiografia de alta resolução no diagnóstico da cardiomiopatia arritmogênica do ventrículo direito do Boxer, 20 cães sem evidências de doença cardíaca estrutural à avaliação ecodopplercardiográfica foram agrupados de acordo com a frequência de arritmias ventriculares, avaliadas pela eletrocardiografia ambulatorial de 24 horas, e submetidos ao exame eletrocardiográfico de alta resolução. Duração do complexo QRS filtrado, duração dos sinais de baixa amplitude (menor que 40µV) dos últimos 40 milissegundos do complexo QRS e raiz quadrada média da voltagem ao quadrado dos últimos 40 milissegundos do complexo QRS (RMS40) foram as variáveis avaliadas. Não foram observadas diferenças significativas entre os grupos em relação às variáveis estudadas. Sendo assim, os resultados do presente estudo sugerem que a eletrocardiografia de alta resolução não é uma ferramenta útil no auxílio diagnóstico da cardiomiopatia arritmogênica do ventrículo direito dos cães da raça Boxer que não apresentam alterações miocárdicas evidentes ou disfunção sistólica.

Transmission electron microscopy for characterization of acrosomal damage after Percoll gradient centrifugation of cryopreserved bovine spermatozoa

The objective of this study was to characterize acrosomal ultrastructure following discontinuous Percoll gradient centrifugation of cryopreserved bovine sperm. Semen was collected from six bulls of different breeds and three ejaculates per bull were evaluated. Frozen semen samples were thawed and the acrosomal region of sperm cells was evaluated by transmission electron microscopy (TEM) before (n = 18) and after (n = 18) Percoll centrifugation. The evaluation of 20 sperm heads from each of the 36 samples analyzed ensured that a large number of cells were investigated. The data were subjected to analysis of variance at a level of significance of 5%. Percoll centrifugation reduced the percentage of sperm exhibiting normal acrosomes (from 61.77 to 30.24%), reduced the percentage of sperm presenting atypical acrosome reactions (from 28.38 to 4.84%) and increased the percentage of sperm exhibiting damage in the acrosome (from 6.14 to 64.26%). The percentage of sperm with typical acrosome reactions was not significantly different before (3.70%) and after (0.67%) centrifugation. TEM distinguished four different types of acrosomal status and enabled ultrastructural characterization of acrosomal injuries. The percentage of sperm exhibiting normal acrosomes decreased and damage in the acrosome was the most frequent acrosomal injury with the Percoll gradient centrifugation protocol utilized.

Use of scanning electron microscopy for the evaluation of intestinal epithelium integrity

Propõe-se, neste trabalho, o uso de microscopia eletrônica de varredura para avaliar perda de epitélio intestinal da mucosa intestinal de pintos machos e fêmeas submetidos a prolongado jejum pós-eclosão de água e ração. Dois segmentos do duodeno, jejuno e íleo por ave foram coletados e processados pelo método de rotina para microscopia eletrônica de varredura. Seis diferentes graus de perda de epitélio intestinal foram determinados: grau 0, vilos normais, sem extrusão; grau 1, vilos com pequenos pontos de extrusão; grau 2, vilos com perda de epitélio no ápice; grau 3, vilos com perda de epitélio na região apical; grau 4, vilos com perda de epitélio em sua metade superior; grau 5: vilos sem epitélio; grau 6: vilo quebrado. As três regiões intestinais das fêmeas apresentaram aproximadamente 90% de seus vilos normais (graus 0 e 1), enquanto nos machos ocorreu 38% de vilos normais no duodeno e jejuno e 85% no íleo. Além disso, machos apresentaram graus mais acentuados de perda de epitélio (graus 3, 4, 5 e 6) que as fêmeas (grau 3). Os dados indicaram que a mucosa intestinal de pintos machos é mais sensível a prolongado jejum pós-eclosão que a de pintos fêmeas. A microscopia eletrônica de varredura pode ser usada como um método de rotina seguro para a caracterização e quantificação de perda de epitélio intestinal.

Observation of the embryonic development in Pseudoplatystoma coruscans (Siluriformes: Pimelodidae) under light and scanning electron microscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Early development of Astronotus ocellatus under stereomicroscopy and scanning electron microscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Three-Dimensional Semiautomatic Road Extraction From a High-Resolution Aerial Image by Dynamic-Programming Optimization in the Object Space

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Description of eggs and nymphal instars of Triatoma baratai Carcavallo & Jurberg, 2000 based on optical and scanning electron microscopy (Hemiptera: Reduviidae: Triatominae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morphology of the eggs of the genus Belminus (Hemiptera: Reduviidae: Triatominae) by optical and scanning electron microscopy

The external morphology of eggs of the species Belminus corredori Galvao & Angulo, 2006, Belminus herreri Lent & Wygodzinsky, 1979 and Belminus ferroae Sandoval, Pabon, Jurberg & Galvao, 2007 is described for the first time using scanning electron microscopy (SEM). Females lay one egg at a time; the shape of the egg is oval with lateral flattening, a rounded caudal area and a true and simple convex operculum. The average size of the egg among these species is 0.51-0.58 mm in length and 0.36-0.4 mm in width. As a generic character we highlight the discovery of a chorion rim with one to four grooves always joined to the micropyles. All species present a clear polygonal pattern only in the operculum and in the egg's cephalic region, while the median and caudal regions show a smooth appearance, features that are shared only with the eggs of the genus Alberprosenia. A discriminant analysis of the polygonal design of the operculum proved to be useful for the identification of the species.