The polygyny threshold model was introduced in the 1960s in order to explain why females in some species choose to mate vith already mated males. Since then, a number of complementary or alternative hypotheses have been suggested. By using a hierarchical testing approach Searcy and Yasukawa (1989) organised the models that proposed to explain the maintenance of territorial polygyny. Here, I point

The effects of aging on the total number and size of fibers, and the proportion and distribution of type 1 (slow twitch) and type 2 (fast twitch) fibers were studied in cross sections (15 mu thick) of autopsied whole m. vastus lateralis from two age groups. Each group consisted of six, previously physically healthy males (mean age 72 +/- 1 years and 30 +/- 6 years, respectively). The size of the m

An experimental design was used to optimize plasmid purification from an alkaline lysate of Escherichia coli cells using PEG-sodium citrate aqueous two-phase systems (ATIPS), and to evaluate the influence of pH, PEG molecular weight, tie line length, phase volume ratio, and lysate load. To build the mathematical model and minimize the number of experiments for the design parameters, response surfa

We construct a connected finite loop space of rank 66 and dimension 1254 whose rational cohomology is not isomorphic as a graded vector space to the rational cohomology of any compact Lie group, hence providing a counterexample to a classical conjecture. Aided by machine calculation we verify that our counterexample is minimal, i.e., that any finite loop space of rank less than 66 is in fact ratio

Background: More sevoflurane was recently found to be required to prevent movement in response to surgical incision in anaesthetized patients subjected to electro-acupuncture (EA) than to sham procedures. The present study was designed to compare differences in movement, dilatation of the pupils, divergence of the eye axes and activity of auditory evoked potentials (AEPs) between patients given an

In this study, we assessed the proliferative response of peripheral blood mononuclear leukocytes (PBML) from 33 children/young adolescents with chronic dyspepsia, to H. pylori LPS in the presence and absence of IL-2 as a T cell growth factor. A rapid urease test (RUT) and a presence of Helicobacter-like organisms (HLO) in the biopsy specimens allowed us to distinguish RUT/HLO-positive (17/33) and

There were three objectives of this study: to investigate possible specificity in the association between specific cardiac defects and chromosomal anomalies; to evaluate ways of categorizing cardiac defects into larger groups with epidemiological similarities that could indicate similarities in etiology or pathogenesis; and to analyze the relationship between specific cardiac defects and diabetes.

Most of the decisive molecular events in biology take place at the protein-water interface. The dynamical properties of the hydration layer are therefore of fundamental importance. To characterize the dynamical heterogeneity and rotational activation energy in the hydration layer, we measured the 17O spin relaxation rate in dilute solutions of three proteins in a wide temperature range extending d

Energy efficiency in the production and transportation of different kinds of biomass in Sweden has been analysed, as well as the change in energy efficiency in a transition from fossil-fuel-based to biomass-based systems. Net energy yields under current production conditions were found to be highest for short-rotation forest (Salix) and sugar beet (about 160 to 170 GJ ha-1 year-1), followed by ley

A green house experiment was designed to test the idea that competition for inorganic nitrogen (N) between plants and heterotrophic microorganisms occurs in soils with high C:N ratios, qualifying for N limited microbial activity, but not at low C:N ratios. The short- term (24 h) N-15 uptake by the grass Festuca gigantea and microorganisms in planted and unplanted soils was determined, and the bact

The aim of this study was to evaluate the validity and reliability of homeostasis model assessment-insulin resistance (HOMA-IR) index, its reciprocal (1/HOMA-IR), quantitative insulin sensitivity check index (QUICKI) and McAuley's index in hypertensive diabetic patients. In 78 patients with hypertension and type II diabetes glucose, insulin and triglyceride levels were determined after a 12-h fast

BACKGROUND: The purpose of this study was to explore relationships between satisfaction with occupational factors, operationalized as occupational status and the total daily occupational situation, and health-related variables among people with schizophrenia. The health-related variables included quality of life, perceived control, sense of coherence, and psychopathology. Gender differences in the

The objective of this study was to find risk factors for suicide by looking for clinical and care/treatment consumption differences between 15 hospitalized suicide attempters, who later committed suicide ("completers''), and 15 suicide attempters who did not ("non-completers''), matched according to sex, age and principal diagnosis. Completers had significantly more often attempted suicide after t

In this small-scale study we investigated the influence of different aspects of context on the language production of children with specific language impairment (SLI). Each of the variables, type of partner, the partner’s interactional style and the type of material used for eliciting conversation, was related to the probability of the use of a set of grammatical constructions by the child. The re

Uncoupling proteins are inner mitochondrial membrane proteins, which dissipate the proton gradient, releasing the stored energy as heat. Five proteins have been cloned, named UCP1, UCP2, UCP3, UCP4 and UCP5/BMCP1. These proteins are structurally related but differ in tissue expression. UCP1 is expressed uniquely in the brown adipose tissue, while UCP2 is widely distributed, UCP3 is mainly restrict

Large and powerful ocean predators such as swordfishes, some tunas, and several shark species are unique among fishes in that they are capable of maintaining elevated body temperatures (endothermy) when hunting for prey in deep and cold water [1-3]. In these animals, warming the central nervous system and the eyes is the one common feature of this energetically costly adaptation [4]. In the swordf

Chlorophyll biosynthesis is a process involving approximate to 20 different enzymatic steps. Half of these steps are common to the biosynthesis of other tetrapyrroles, such as heme. one of the least understood enzymatic steps is formation of the isocyclic ring, which is a characteristic feature of all (bacterio)chlorophyll molecules. In chloroplasts, formation of the isocyclic ring is an aerobic r