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Restricted mesh simplification using edge contractions

We consider the problem of simplifying a triangle mesh using edge contractions, under the restriction that the resulting vertices must be a subset of the input set. That is, contraction of an edge must be made onto one of its adjacent vertices. In order to maintain a high number of contractible edges under this restriction, a small modification of the mesh around the edge to be contracted is allow

Causes and consequences of excess resistance in cryptobiotic metazoans

Despite more than 200 yr of recognition that some microscopic metazoans survive environmental conditions far beyond those experienced in nature while in a cryptobiotic state, this phenomenon has received little attention from evolutionary biologists. The excess environmental resistance exhibited by cryptobiotic organisms cannot be viewed as an adaptation within current evolutionary biology. Rather

Expression and characterization of the two flavodoxin proteins of Bacillus subtilis, YkuN and YkuP: Biophysical properties and interactions with cytochrome p450 BioI

The two flavodoxins (YkuN and YkuP) from Bacillus subtilis have been cloned, overexpressed in Escherichia coli and purified. DNA sequencing, mass spectrometry, and flavin-binding properties showed that both YkuN and YkuP were typical short-chain flavodoxins (158 and 151 amino acids, respectively) and that an error in the published B. subtilis genome sequence had resulted in an altered reading fram

Whole gene family expression and drought stress regulation of aquaporins

Since many aquaporins (AQPs) act as water channels, they are thought to play an important role in plant water relations. It is therefore of interest to study the expression patterns of AQP isoforms in order to further elucidate their involvement in plant water transport. We have monitored the expression patterns of all 35 Arabidopsis AQPs in leaves, roots and flowers by cDNA microarrays, specially

Testing for error correction in panel data

This paper proposes new error correction-based cointegration tests for panel data. The limiting distributions of the tests are derived and critical values provided. Our simulation results suggest that the tests have good small-sample properties with small size distortions and high power relative to other popular residual-based panel cointegration tests. In our empirical application, we present evi

Should boxing be banned?

Should boxing be banned? Do the ever-so-obvious risks outweigh everyone's freedom to choose whether to expose oneself to these risks by taking up the sport? On an official level, the RCN in the UK has taken its stand--it does not! So has also the British Medical Association (BMA)--it does! With few exceptions, the responding nurses from Europe, America, and Australia in this month's column seem to

Self-respect, dignity and confidence: conceptions of integrity among male patients

Background. Integrity is a complex and important concept in ethical reasoning and in nursing care. Integrity is part of being a human being, a wholeness, and in this sense it also refers to health. Preserving patients' integrity is an important aspect of nursing care, as a number of situations arise in which they can feel threatened or violated. Integrity can also refer to acting according to gene

Storms can cause Europe-wide reduction in forest carbon sink

Disturbance of ecosystems is a major factor in regional carbon budgets, and it is believed to be partly responsible for the large inter-annual variability of the terrestrial part of the carbon balance. Forest fires have so far been considered as the most important disturbance but also other forms of disturbance such as insect outbreaks or wind-throw might contribute significantly to the largely un

Different Markers of Alcohol Consumption, Smoking and Body Mass Index in Relation to Risk of Pancreatic Cancer. A Prospective Cohort Study within the Malmö Preventive Project.

Background/Aim: The association between alcohol consumption and pancreatic cancer is not clear. This study investigates different prediagnostic measurements of alcohol consumption, a laboratory marker (gamma-glutamyltransferase; gamma-GT), and a score measuring alcohol addiction (Mm-MAST), in relation to the risk of pancreatic cancer. Furthermore, the study investigated whether smoking and alcohol

Radiation of extant marsupials after the K/T boundary: Evidence from complete mitochondrial genomes

The complete mitochondrial (mt) genomes of five marsupial species have been sequenced. The species represent all three South American orders (Didelphimorphia, Paucituberculata, and Microbiotheria). Phylogenetic analysis of this data set indicates that Didelphimorphia is a basal marsupial lineage followed by Paucituberculata. The South American microbiotherid Dromiciops gliroides (monito del monte)

Molecular and morphological evolution in the Physciaceae (Lecanorales, lichenized Ascomycotina), with special emphasis on the genus Rinodina

A phylogenetic hypothesis based on nuclear ITS sequence data is presented for the family Physciaceae, based on various representatives of foliose and fruticose groups and a number of species selected from the crustose genera Rinodina and Buellia s.l. The analysis supports the monophyly of the Physcia- and the Buellia-groups. This is in agreement with existing morphological evidence, particularly a

Resistivity imaging in steep and weathered terrains

In areas where tectonics and weathering have hydrogeological significance, electrical methods can assist in mapping the subsurface. In this work, resistivity imaging was used to map fractures, faults and quartz veins emplaced in strongly weathered volcanic rocks. The aim was to map geological units related to the formation of groundwater systems in the Rio Artiguas basin, Nicaragua. Eight 2D resis

Perivascular cells expressing annexin A5 define a novel mesenchymal stem cell-like population with the capacity to differentiate into multiple mesenchymal lineages

The annexin A5 gene (Anxa5) was recently found to be expressed in the developing and adult vascular system as well as the skeletal system. In this paper, the expression of an Anxa5-lacZ fusion gene was used to define the onset of expression in the vasculature and to characterize these Anxa5-lacZ-expressing vasculature-associated cells. After blastocyst implantation, Anxa5-lacZ-positive cells were

Weight and height at 4 and 7 years of age in children born to mothers with a high intake of fish contaminated with persistent organochlorine pollutants.

In Sweden the main exposure route for persistent organochlorine pollutants (POP) is through consumption of fatty fish from the Baltic Sea (off the eastern coast). The present study aimed to investigate whether intrauterine exposure for POP may have negative impact on children's weight and height at 4 and 7 years of age, respectively. The study included 174 fishermen's wives from the Swedish east c

Effects of the pyrethroid insecticide, cypermethrin, on a freshwater community studied under field conditions. I. Direct and indirect effects on abundance measures of organisms at different trophic levels

The effects of the pyrethroid insecticide cypermethrin on a natural freshwater community were studied in small in situ enclosures over an 11-day period. The experiment was conducted in a eutrophic lake using a regression design that included three untreated controls and a gradient of six unreplicated cypermethrin concentrations, ranging from 0.01 to 6.1 mug/l. This paper is the first in a series o

Nasal indices of eosinophilic and exudative inflammation in bakery-workers

Aims: Rhinitis symptoms frequently occur in bakery-workers. Yet, little is known about the pathophysiology of this condition. The objective of the present study was to examine nasal indices of inflammation in relation to occupational dust exposure, occupational rhinitis according to defined criteria, rhinitis symptoms associated to the workplace, and occupational sensitization in bakery-workers. M

Impact of low copy repeats on the generation of balanced and unbalanced chromosomal aberrations in mental retardation

Low copy repeats (LCRs) are stretches of duplicated DNA that are more than 1 kb in size and share a sequence similarity that exceeds 90%. Non-allelic homologous recombination (NAHR) between highly similar LCRs has been implicated in numerous genomic disorders. This study aimed at defining the impact of LCRs on the generation of balanced and unbalanced chromosomal rearrangements in mentally retarde