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Magnetic compass of migratory Savannah sparrows is calibrated by skylight polarizarion and sunrise and sunset

Migratory birds use compass systems derived from the geomagnetic field, the stars, the sun and polarized light patterns. We tested whether birds use a single underlying reference system for calibration of these compasses and, specifically, whether sunset and sunrise polarized light cues from the region of the sky near the horizon are used to calibrate the magnetic compass. We carried out orientati

Long-term outcome in term breech infants with low Apgar score--a population-based follow-up

OBJECTIVE: To investigate the relation between low Apgar score in breech infants and handicap in childhood. STUDY DESIGN: A case-control study. A questionnaire to mothers of 323 non-malformed, singleton infants delivered in breech presentation at term, 105 cases with Apgar score below 7 at 5 min and 218 controls. RESULTS: Four cases (4.6%) and one control (0.5%) had cerebral palsy. In infants with

The Effect of Having an Affected Parent or Sibling on Invasive and In Situ Skin Cancer Risk in Sweden

Studies suggest that skin cancer aggregates within families; however, the risk of skin cancer associated with having an affected sibling or parent by subtype, tumor site, and age at diagnosis has not been established. The 2006 update of the Swedish Family-Cancer Database was used to calculate standardized incidence ratios (SIRs), representing the ratio of cancer risk among individuals with affecte

Cross-Sectional and Serial Correlation in a Small-Sample Homogeneous Panel Data Unit Root Test

In this paper, response surface parameters are provided that can be used to obtain critical values for an augmentation of an existing homogeneous panel data unit root test. The augmentation is performed to account for serial correlation in the disturbances. As the existing panel data unit root test is robust against cross-sectional correlation, the augmented test is robust against both cross-secti

Purification, characterization, and expression of rat intestinal alkaline sphingomyelinase.

Intestinal alkaline sphingomyelinase (SMase) has physiological roles in the digestion of sphingomyelin (SM) and clinical implications in colonic carcinogenesis. In the present work, the enzyme from rat has been purified 1,589-fold with 11% recovery by elution of the intestine with bile salt, precipitation of the proteins by acetone, and several types of chromatographies. Its molecular mass was 58

A metal binding site in the catalytic subunit of anaerobic ribonucleotide reductase.

A Zn(Cys)4 center has been found in the C-terminal region of the crystal structure of the anaerobic class III ribonucleotide reductase (RNR) from bacteriophage T4. The metal center is structurally related to the zinc ribbon motif and to rubredoxin and rubrerythrin. Mutant enzymes of the homologous RNR from Escherichia coli, in which the coordinating cysteines, conserved in almost all known class I

Characterization of calretinin I-II as an EF-hand, Ca2+, H+-sensing domain

Calretinin, a neuronal protein with well-defined calcium-binding properties, has a poorly defined function. The pH dependent properties of calretinin (CR), the N-terminal (CR I-II), and C-terminal (CR III-VI) domains were investigated. A drop in pH within the intracellular range (from pH 7.5 to pH 6.5) leads to an increased hydrophobicity of calcium-bound CR and its domains as reported by fluoresc

Error analysis of coarse-graining for stochastic lattice dynamics

The coarse‐grained Monte Carlo (CGMC) algorithm was originally proposed in the series of works [M. A. Katsoulakis, A. J. Majda, and D. G. Vlachos, J. Comput. Phys., 186 (2003), pp. 250–278; M. A. Katsoulakis, A. J. Majda, and D. G. Vlachos, Proc. Natl. Acad. Sci. USA, 100 (2003), pp. 782–787; M. A. Katsoulakis and D. G. Vlachos, J. Chem. Phys., 119 (2003), pp. 9412–9427]. In this paper we further

Severe inbreeding depression in a wild wolf (Canis lupus) population

The difficulty of obtaining pedigrees for wild populations has hampered the possibility of demonstrating inbreeding depression in nature. In a small, naturally restored, wild population of grey wolves in Scandinavia, founded in 1983, we constructed a pedigree for 24 of the 28 breeding pairs established in the period 1983-2002. Ancestry for the breeding animals was determined through a combination

Approximate distance oracles for graphs with dense clusters

Let H-1 = (V, F-1) be a collection of N pairwise vertex disjoint O(1)-spanners where the weight of an edge is equal to the Euclidean distance between its endpoints. Let H-2 = (V, F-2) be a graph on V with M edges of non-negative weight. The union of the two graphs is denoted G = (V, F-1 boolean OR F-2). We present a data structure of size O(M-2 + V log V) that answers (1 + epsilon)-approximate sho

Time to extinction in relation to mating system and type of density regulation in populations with two sexes

1. Population viability models usually consider only the female segment of the population. However, random variation in sex ratio as well as the mating system may also affect variation in fitness among females. Here we develop population models incorporating demographic stochasticity in both sexes. Furthermore, we consider the effects on the estimated time to extinction and whether density regulat

BAL fluid derived fibroblasts differ from biopsy derived fibroblasts in systemic sclerosis.

Growth of fibroblasts from bronchoalveolar lavage fluid (BALF) in patients with systemic sclerosis (SSc) has previously been described. The purpose of the present study was to characterise fibroblasts from BALF and bronchial biopsies from SSc patients with alveolitis and from controls, to analyse fibroblast proliferation, migration, stress fibres and proteoglycan production. BALF and bronchial bio

Influence of adhesins on the interaction of Escherichia coli with human phagocytes

The fitness between bacterial adhesins and target cell receptors, determining bacterial adherence to epithelial cells in urinary tract infections, was shown to influence also the interaction with human polymorphonuclear leukocytes (PMNL). Two sets of homogenic strains, constructed to express either, both, or none of the globotetraosylceramide-sensitive (GS) adhesins specific for globoseries glycol

DNA-lipid systems. A physical chemistry study

It is well known that the interaction of polyelectrolytes with oppositely charged surfactants leads to an associative phase separation; however, the phase behavior of DNA and oppositely charged surfactants is more strongly associative than observed in other systems. A precipitate is formed with very low amounts of surfactant and DNA. DNA compaction is a general phenomenon in the presence of multiv

Tyrosine hydroxylase expression is unstable in a human immortalized mesencephalic cell line - Studies in vitro and after intracerebral grafting in vivo

We have studied the stability of the dopaminergic phenotype in a conditionally immortalized human mesencephalic cell line, NIESC2.10. Even though MESC2.10 cells exhibit features of dopaminergic neurons in vitro, none of the cells expressed tyrosine hydroxylase (TH) after transplantation into a rat model of Parkinson's disease. We examined whether this is caused by cell death or loss of transmitter

Effects of duration of type 2 diabetes mellitus on insulin secretion.

Objective: To gain insight into the effects of duration of type 2 diabetes on insulin secretion in patients with type 2 diabetes mellitus. Methods: C-peptide concentrations were measured every 2 years before and after intravenous injection of 1 mg of glucagon in 89 patients with type 2 diabetes (51 men and 38 women) as part of the Rochester Diabetic Neuropathy Study in those subjects who particip

New pharmacologic targets for the treatment of the overactive bladder: an update.

Although currently available antimuscarinic agents are the standard of care for overactive bladder (OAB), they are limited by certain side effects, particularly dry mouth and constipation. Research aimed at discovering new therapies for OAB has resulted in the identification of some promising drugs. Investigations of pharmacologic targets in the central nervous system (CNS) have yielded encouragin

Permian plant macrofossils from Fossilryggen, Vestfjella, Dronning Maud Land

A low diversity plant macrofossil assemblage described from the northern section of Fossiryggen, Vestfiella, Dronning Maud Land, Antarctica, is dominated by matted leaf impressions of Glossopteris sp. cf. G communis Feistmantel and Glossopteris sp. cf. G spatulata Pant A Singh, and in situ finely branched Vertebraria indica Royle rootlets. Equisetalean stems, rhizomes and leaf whorls (Pkyllotheca