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Temperature, genetic and hydroperiod effects on metamorphosis of brown frogs Rana arvalis and R-temporaria in the field

Time for metamorphosis and metamorph size of moor frogs Rana arvalis and common frogs R. temporaria were measured in 22 ponds for 18 years. Environmental data in these ponds were also measured. Metamorphosis of the frogs took place from the beginning of June to the beginning of August. When both species were found in one pond, the common frogs metamorphosed up to 20 days earlier than the moor frog

Comparison of alternant and nonalternant aromatic bridge systems with respect to their ET-properties

The bis(triarylamine) systems 1-5 were synthesized and investigated by spectroscopic and electrochemical methods. They all have an aromatic five-membered ring system in common as a central part of their pi-electron bridge. The absorption spectra are presented. All compounds undergo five oxidations whereupon only the first two are reversible under semi-infinite cyclic voltammetry conditions. The sp

5-Hydroxytryptamine receptor profile in healthy and diseased human epicardial coronary arteries

STUDY OBJECTIVE--The aim of the study was to investigate the receptor events that mediate the vascular effects of 5-hydroxytryptamine (5-HT) on human coronary arteries, since 5-HT has long been thought to play a role in coronary artery vasospasm. DESIGN--Recently available selective receptor agonists and antagonists were used to examine the 5-HT receptor subtypes present in human epicardial corona

A model of triploid endosperm evolution driven by parent-offspring conflict

The parental investment in angiosperms comprises the endosperm, a nutrient reserve that is used during seed development. The endosperm contains genes from both parents. The most common endosperm form is the 3n Polygonum-type with more maternal genetic influence than paternal, i.e. with two maternal nuclei and one paternal nucleus. The evolutionary original state is thought to be a diploid endosper

Fisher information analysis for two-dimensional microwave tomography

In this paper, a Fisher information analysis is employed to establish some important physical performance bounds in microwave tomography. As a canonical problem, the two-dimensional electromagnetic inverse problem of imaging a cylinder with isotropic dielectric losses is considered. A fixed resolution is analysed by introducing a finite basis, i.e., pixels representing the material properties. The

KSHV complement control protein mimics human molecular mechanisms for inhibition of the complement system.

Kaposi's sarcoma-associated human herpesvirus (KSHV) is thought to cause Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman's disease. Previously, we reported that the KSHV complement control protein (KCP) encoded within the viral genome is a potent regulator of the complement system; it acts both as a cofactor for factor I and accelerates decay of the C3 convertases (Spiller,

Tri-trophic effect on predator feeding: consumption by the carabid Harpalus affinis of Heliothis armigera caterpillars fed on proteinase inhibitor-containing diet

During the breeding of our major crop plants for high yield and edibility, several desirable traits, including resistance to pest insects, have been lost (Gatehouse et al., 1991). Genetic engineering is now vigorously seeking to reinsert such genes into crop plants, making them toxic or less palatable for herbivorous pests. One class of inhibitors under study are protease/proteinase inhibitors. Th

Location of Two Seams in the Proximity of the C-2v pi pi Minimum Energy Path of Formaldehyde

Photochemical reactions rationalization is a key aspect for the understanding and setup of novel experiment and novel photoinitiated pathways. In this respect, the relationship between minimum energy paths over an excited-state and the intersection to lower potential energy surfaces is fundamental. In order to help the understanding of this relationship, in this study we present a novel kind of co

CC chemokine ligand 20 partially controls adhesion of naive B cells to activated endothelial cells under shear stress

Chemokines are thought to control lymphocyte recruitment to the inflamed endothelium. To dissect chemokine-mediated adhesion, binding of ex vivo isolated splenocytes to tumor necrosis factor (TNF)-activated endothelial cells was analyzed under shear stress. We observed specific adhesion of naive follicular B cells, which could be blocked by pertussis toxin. This indicated a G protein-mediated bind

An Efficient Numerical Algorithm for Cracks Partly in Frictionless Contact

An algorithm for a loaded crack partly in frictionless contact is presented. The problem is nonlinear in the sense that the equations of linear elasticity are supplemented by certain contact inequalities. The location of a priori unknown contact zones and the solutions to the field equations must be determined simultaneously. The algorithm is based on a rapidly converging sequence of relaxed Fredh

Loop-shaping design of PID controllers with constant Ti/Td ratio

This paper presents new tuning rules for PIDcontrollers based on loop shaping. Previous research has shownthat maximization of the integral gain subject to constraints on the maximumsensitivity is an efficient design method for PI controllers, but thatadditional constraints are needed for design of PID controllers. Inthis paper, an additional constraint is obtained by restricting theratio between

Interactions between family members and staff in intensive care units-An observation and interview study.

Background: Research about interactions between family members and staff are sparse, although family members’ needs and experiences in intensive care units are well researched areas. Aim: The aim was to describe and interpret interactions between family members and staff in intensive care units. Methods: Interviews (n=24) with family members and repeated observations of interactions of family me

Structural Basis for Substrate Specificity Differences of Horse Liver Alcohol Dehydrogenase Isozymes

A structure determination in combination with a kinetic study of the steroid converting isozyme of horse liver alcohol dehydrogenase, SS-ADH, is presented. Kinetic parameters for the substrates, 5β-androstane-3β,17β-ol, 5β-androstane-17β-ol-3-one, ethanol, and various secondary alcohols and the corresponding ketones are compared for the SS- and EE-isozymes which differ by nine amino acid substitut

The decorin sequence SYIRIADTNIT binds collagen type I.

Decorin belongs to the small leucine-rich repeat proteoglycan family, interacts with fibrillar collagens, and regulates the assembly, structure, and biomechanical properties of connective tissues. The decorin-collagen type I-binding region is located in leucine-rich repeats 5–6. Site-directed mutagenesis of this 54-residue-long collagen-binding sequence identifies Arg-207 and Asp-210 in leucine-ri

Three-Day Enteral Exposure to a Red Kidney Bean Lectin Preparation Enhances the Pancreatic Response to CCK Stimulation in Suckling Pigs.

Background: A reason for the digestive problems that often occur around early weaning in piglets could be that the pancreas is not yet fully developed and the enzymes required for degradation of the solid food are not secreted in enough amounts. Objectives: The aim of the study was to investigate the possibility of inducing pancreas maturation with enhanced enzyme secretion. Methods: 10-day-old su

Seasonality of month of birth differs between type 1 diabetes patients with pronounced beta-cell autoimmunity and individuals with lesser or no beta-cell autoimmunity

Objective: To establish whether children with type 1 diabetes mellitus (T1D) with signs of pronounced beta-cell-specific autoimmunity as reflected by high autoantibody titers or positivity for several beta-cell-specific autoantibodies show a different pattern of month of birth (MOB) compared with children with T1D and low beta-cell autoimmunity and that of the general population. Research design a