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Mitotic instability in cancer - Is there method in the madness?

It has been known for more than a century that neoplastic cells often exhibit disturbances of the mitotic process, but the causes have only recently been thoroughly explored. In many cancers, a combination of cell cycle checkpoint deficiency and abnormal shortening of telomeres predisposes to unbalanced chromosome segregation at cell division and the development of complex genomic rearrangements.

Scope of nucleotide chemistry as studied by isothermal titration microcalorimetry

The area of isothermal titration microcalorimetric (ITC) studies on solution systems involving nucleotides is reviewed. 62 references are cited. About 25 ITC studies on nucleotide systems have been published during the last two decades. The main part (ca 95%) of these papers deal with nucleotide-protein interactions and one paper involves nucleotide-nucleotide binding studies. The results of such

Neuronal death in nigral grafts in the absence of poly (ADP-ribose) polymerase activation

The exact causes of the extensive cell death in nigral transplants are still unknown. Since poly-(ADP-ribose) polymerase (PARP) overactivation has been implicated in neuronal death, we examined the effects of PARP on the survival of nigral grafts by using donor tissue from PARP knock-out or wild-type mice. Eight hours after preparation of the nigral cell suspension, cell damage was quantified by m

Concentrations of Metals, beta-Amyloid and Tau-Markers in Cerebrospinal Fluid in Patients with Alzheimer's Disease

Background/Aims: In this study, metal concentrations were related to the levels of well-known Alzheimer markers in cerebrospinal fluid (CSF), such as amyloid-beta (A beta), total tau (T-tau) and phosphorylated-tau (P-tau). Methods: Concentrations of 19 metals (Mg, Ca, V, Mn, Fe, Co, Ni, Cu, Zn, Se, Rb, Sr, Mo, Cd, Sn, Sb, Cs, Hg and Pb by inductively coupled plasma-mass spectrometry) and the level

Large scale differentiation and population dynamics in tundra plants and vegetation

The inclusion of the botanical projects in the Swedish-Russian Tundra Ecology -94 expedition provided new information on the ecology of tundra plants. The vegetation patterns on different scales were documented, and interpreted as the result of a complex interaction with environmental factors. The distribution of fruticose lichens was studied, and it was shown that these lichens rely on different

Traveling Architects – A New Way of Herding Cats

Making software developers work towards a common goal may be likened to herding cats. If we further spread developers around the globe, we run increased risks of being unable to design and impose coherent software architectures on projects, potentially leading to lower quality of the resulting systems. Based on our experiences in a large, distributed research and development project, PalCom, we pr

Self-diffusion of nonfreezing water in porous carbohydrate polymer systems studied with nuclear magnetic resonance

Water is an integral part of the structure in biological porous materials such as wood and starch. A problem often encountered in the preparation of samples for, e.g., electron microscopy is that removal of water leads to a decreasing distance between supermolecular structural elements and a distortion of the structure. It is, therefore, of interest to find methods to investigate these materials i

Jump Spillover in International Equity Markets

In this article we study jump spillover effects between a number of country equity indexes. In order to identify the latent historical jumps of each index, we use a Bayesian approach to estimate a jump-diffusion model on each index. We look at the simultaneous jump intensities of pairs of countries and the probabilities that jumps in large countries cause jumps or unusually large returns in other

Measured CMOS Switched High-Quality Capacitors in a Reconfigurable Matching Network

Switched capacitors are here investigated for use in reconfigurable matching networks, particularly for DVB-H frequencies. A 0.13 um CMOS circuit is evaluated through both simulations and measurements. Source grounded NMOS transistors are used to switch high quality metal capacitors located above metal layer 8. The quality factor and tuning range depend on frequency, switch voltage, capacitor size

Effects of grassland abandonment, restoration and management on butterflies and vascular plants

When semi-natural pastures are abandoned, specialized grassland species are lost as a consequence of succession. As a counter-measure, previously abandoned grasslands may be restored by clearing shrubs and trees and re-introducing grazing livestock. In order to examine the effects of this type of habitat restoration, we compared species richness of plants and of specialized plants thought to be de

Sample preparation effects on the compaction properties of Swedish fine-grained tills

Fine-grained tills are a dominant feature of the drift geology of Sweden. Until recently their use in earthworks applications has been limited due to the plentiful supply of naturally occurring gravel and crushed rock, and their high sensitivity to moisture content change which often leads to the view that fine-grained tills are problem soils. Environmental and economic factors are, however, leadi

Laparoscopic gastrostomy in children with congenital heart disease

Aim: The aim of this study was to study the type and frequency of complications and change in weight after a laparoscopic gastrostomy procedure in 31 children with congenital heart disease, comparing patient groups of children with univentricular and biventricular circulation, and with completed and uncompleted cardiac surgery. Methods: The method used was that of a retrospective study of all 31 c

Competitive adsorption between phosphate and carboxylic acids: quantitative effects and molecular mechanisms

The competitive adsorption at the water-goethite interface between phosphate and a carboxylic acid, either oxalate, citrate, 1,2,3,4-butanetetracarboxylic acid (BTCA), mellitate or Suwannee River Standard Fulvic Acid 1S101F (FA), was investigated over a wide pH range (3-9) by means of batch experiments and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The quantit

Aspects of haemophilia prophylaxis in Sweden.

Prophylactic treatment of haemophilia has been gaining acceptance as the optimal therapeutic option in an increasing number of haemophilia centres in the developed world in recent years. This paper focus on three aspects of prophylactic therapy: when to start treatment, venous access and the dose/dose interval. Evidence is in favour of prophylactic treatment to be started at an early age using eit

Walking The Cognisphere - Navigation and Digital Media on The Go

The paper deals with the ways an advanced digital technology like GPS (Global Positioning System) is integrated with the mundane practices of wayfinding and moving on foot. I will use N Katherine Hayles take on the concept cognisphere: ”The cognisphere gives a name and shape to the globally interconnected cognitive systems in which humans are increasingly embedded.” The concept deals with the ways

Active Logic and Practice

The problem of finding a suitable formal approach to describe on-going reasoning process has been open since the very beginning of AI. In this paper we argue that active logic might be a formalism useful in this context. Active logic is first introduced, then we analyze resource limitations that constrain the space of possible practical realisations of such reasoners. Finally some steps towards cr

Risk of musculoskeletal disorders among females and males in repetitive/constrained work

This paper combines epidemiological data on musculoskeletal morbidity in 40 female and 15 male occupational groups (questionnaire data 3720 females, 1241 males, physical examination data 1762 females, 915 males) in order to calculate risk for neck and upper limb disorders in repetitive/constrained vs. varied/mobile work and further to compare prevalence among office, industrial and non-office/non-

Electrochemistry of guanine and 8-oxoguanine at gold electrodes

Guanine was electrochemically oxidised at polycrystalline gold electrodes. The potential for guanine oxidation at pH 7.4 was +690 mV versus AgAgCl when extrapolated to a scan rate of 3 mV s(-1). Kinetic analysis revealed the initial irreversible 2e(-) oxidation of guanine, achieved with fast scan cyclic voltammetry. At scan rates lower than 5 V s(-1), the 2e(-) oxidation changed to the extensive 4