Biological Evidence (biological + evidence)

Distribution by Scientific Domains

Selected Abstracts

Review of: Forensic Biology: Identification and DNA Analysis of Biological Evidence

Lori E. Baker Ph.D.
No abstract is available for this article. [source]

Instream Flow Science For Sustainable River Management,

Geoffrey E Petts
Abstract:, Concerns for water resources have inspired research developments to determine the ecological effects of water withdrawals from rivers and flow regulation below dams, and to advance tools for determining the flows required to sustain healthy riverine ecosystems. This paper reviews the advances of this environmental flows science over the past 30 years since the introduction of the Instream Flow Incremental Methodology. Its central component, Physical HABitat SIMulation, has had a global impact, internationalizing the e-flows agenda and promoting new science. A global imperative to set e-flows, including an emerging trend to set standards at the regional scale, has led to developments of hydrological and hydraulic approaches but expert judgment remains a critical element of the complex decision-making process around water allocations. It is widely accepted that river ecosystems are dependent upon the natural variability of flow (the flow regime) that is typical of each hydro-climatic region and upon the range of habitats found within each channel type within each region. But as the sophistication of physical (hydrological and hydraulic) models has advanced emerging biological evidence to support those assumptions has been limited. Empirical studies have been important to validate instream flow recommendations but they have not generated transferable relationships because of the complex nature of biological responses to hydrological change that must be evaluated over decadal time-scales. New models are needed to incorporate our evolving knowledge of climate cycles and morphological sequences of channel development but most importantly we need long-term research involving both physical scientists and biologists to develop new models of population dynamics that will advance the biological basis for 21st Century e-flow science. [source]

Monitoring acute inflammatory processes in mouse muscle by MR imaging and spectroscopy: a comparison with pathological results

Jesús Ruiz-Cabello
Abstract We have studied an animal model of acute local inflammation in muscle induced by Aspergillus fumigatus by using magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). We have compared our data to those found using histopathology and segmentation maps obtained by the mathematical processing of three-dimensional T2 -weighted MRI data via a neural network. The MRI patterns agreed satisfactorily with the clinical and biological evidence of the phases of acute local infection and its evolution towards chronicity. The MRS results show a statistically significant increase in inorganic phosphate and a significant decrease in phosphocreatine levels in the inflamed region. Image segmentation made with a self-organizing, neural-network map yielded a set of ordered representatives that remained constant for all animals during the inflammatory process, allowing a non-invasive, three-dimensional identification and quantification of the inflamed infected regions by MRI. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Histopathological varieties of oral carcinoma in situ: Diagnosis aided by immunohistochemistry dealing with the second basal cell layer as the proliferating center of oral mucosal epithelia

Takanori Kobayashi
To make reproducible diagnoses for oral carcinoma in situ (CIS), combined immunohistochemistry directed at the positioning of squamous cell proliferation (Ki-67) and differentiation (keratin (K) 13 and K19) was used, both of which support histological evaluations by providing biological evidence. Normal/hyperplastic epithelia was defined by K19+ cells only in the first basal layer, K13+ cells in the third basal and upper layers, and sporadic Ki-67+ cells in the second basal layer. These profiles indicated that a proliferating center of the oral epithelium is located in the parabasal cell layer, and K19 and K13 can be regarded as markers for basal and prickle cells, respectively. Epithelial dysplasia was characterized by irregular stratification of Ki-67+ cells and the absence of K19/K13 in proliferating cells. Irregular emerging of K19+ and K13+ cells in proliferating foci with unique stratification of atypical Ki-67+ cells indicated CIS. When the definition was applied, surgical margins in 172 recurrent cases were shown to contain CIS (39.4%) and squamous cell carcinoma (55.8%), indicating that the new diagnostic criteria for CIS reflected clinical behaviors of the cases. The results indicate that oral CIS contain more histological variations, especially those with definite keratinization, than what had been previously defined. [source]

Secular changes in stature and body mass index for Chinese youth in sixteen major cities, 1950s,2005

Cheng-Ye Ji
Evidence shows a secular trend in physical growth in China in recent years. We analyze the secular trend of stature and body mass index (BMI) for the period 1950s,2005 to provide biological evidence for policy-makers to identify measures for improving Chinese children's health. Data come from the historical records in 1950s and the successive cycles of the Chinese National Survey on Student's Constitution and Health. Subjects were 7- to 18-year-old youth from 16 cities. Sex,age differences in mean stature and BMI values between the surveys were analyzed, and the increments per decade were compared. An overall positive secular trend was found in 1950s,2005. Mean stature of the 18-year olds increased from 166.6 to 173.4 cm for males and from 155.8 to 161.2 cm for females, yielding rates of 1.3 and 1.1 cm/decade; the overall increments of BMI values were 2.6 for males and 1.8 for females, yielding rates of 0.8 and 0.6/decade, respectively. The most significant changes occurred during puberty. The overall positive secular trend is closely associated with the socioeconomic progress and the improvement of livelihood. Strong evidence suggests that in China this trend will be continued for many years. Further studies are needed to explore how to ensure healthy changes for poorer rural youth. Effective preventive strategies and measures should be taken to prevent the progressive increase in the prevalence of childhood obesity accompanying this trend. Am. J. Hum. Biol., 2008. © 2008 Wiley-Liss, Inc. [source]

Southern French Neolithic populations: Isotopic evidence for regional specificities in environment and diet

Estelle Herrscher
Abstract The Middle Neolithic of the Northwestern Mediterranean area (,4500,3500 BC cal) is characterized by the development of food production techniques as well as by increasing social complexity. These characteristics could have had an impact on human dietary patterns. To evaluate human dietary practices and lifeways of the Middle Neolithic populations from the South of France, stable carbon and nitrogen isotope analysis was carried out on 57 human and 53 faunal bones from seven archaeological sites located in the Languedoc and Garonne regions between 20 and 100 km from the Mediterranean Sea, respectively. Results show regional differences in carbon isotope values. Animal and human bones from the Languedoc region are significantly enriched in 13C relative to the Garonne. Conversely, human and dog bones from the Garonne region are significantly enriched in 15N compared to human and dog bones from the Languedoc region. These results highlight the importance of the local ecosystem in human and animal diet as well as a regional differentiation of palaeodietary behavior, which probably relates to economic and social factors. The comparison of stable isotope data with archaeological and biological evidence does not show any significant intra- or interpopulation differences. However, the presence of human outliers suggests that migration probably occurred, perhaps in relation to the trade of animals and/or materials. This study also highlights the importance of investigating local animal stable isotope values for the interpretation of human palaeodiet. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source]


Sophie S Nightingale
The cause of testicular ectopia has long been a mystery, and over the years, many hypotheses have been suggested to explain the condition. The most famous of these hypotheses is that of the ,Tails of Lockwood'. This developed from a paper written in 1888 by Charles Barrett Lockwood. Although little evidence has ever been found to corroborate this hypothesis, it remains in many textbooks and journal articles to the present day. In the 21st century, this theory should no longer be given as the cause for ectopic testes. Current biological evidence supports a complex process of growth, by elongation and migration of the gubernaculum, rather than a simple mechanical process of testicular descent, as proposed in the 18th century. [source]

A warm thermal enclave in the Late Pleistocene of the South-eastern United States

Dale A. Russell
ABSTRACT Physical and biological evidence supports the probable existence of an enclave of relatively warm climate located between the Southern Appalachian Mountains and the Atlantic Ocean in the United States during the Last Glacial Maximum. The region supported a mosaic of forest and prairie habitats inhabited by a "Floridian" ice-age biota. Plant and vertebrate remains suggest an ecological gradient towards Cape Hatteras (35°N) wherein forests tended to replace prairies, and browsing proboscideans tended to replace grazing proboscideans. Beyond 35°N, warm waters of the Gulf Stream were deflected towards the central Atlantic, and a cold-facies biota replaced "Floridian" biota on the Atlantic coastal plain. Because of niche diversity and relatively benign climate, biodiversity may have been greater in the south-eastern thermal enclave than in other unglaciated areas of North America. However, the impact of terminal Pleistocene megafaunal extinctions may also have been shorter and more severe in the enclave than further north. A comparison with biotic changes that occurred in North America approximately 55 million years (ma) ago at the Paleocene-Eocene Thermal Maximum suggests that similar processes of change took place under both ice-house and greenhouse climates. [source]