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Rapid caspase-dependent cell death in cultured human breast cancer cells induced by the polyamine analogue N-1,N-11-diethylnorspermine

The spen-nine analogue N-1,N-11-diethylnorspermine (DENSPM) efficiently depletes the cellular pools of putrescine, spermidine and spermine by down-regulating the activity of the polyamine biosynthetic enzymes and up-regulating the activity of the catabolic enzyme spermidine/spermine N-1-acetyltransferase (SSAT). In the breast cancer cell line L56Br-Cl. treatment with 10 muM DENSPM induced SSAT act

The influence of non-dissipative quantities in kinematic hardening plasticity

A kinematic hardening plasticity model valid for finite strains is presented. The model is based on the well-known multiplicative split of the deformation gradient into an elastic and a plastic part. The basic ingredient in the formulation is the introduction of locally defined configurations center configurations- which are associated with deformation gradients that are used to characterize the k

The arthropod community of Scots pine (Pinus sylvestris L.) canopies in Norway

We summarise the findings of arthropods collected by fogging the canopy of 24 pine trees in two sites in Eastern and Western Norway. From the samples, taken in 1998 and in 1999, almost 30,000 specimens were determined to 512 species, with Diptera being most species rich (210 species), followed by Coleoptera (76 species) and Araneae (49 species). Of the 96 new species records, nine were new to scie

Tissue damage in heated carrot slices. Comparing mild hot water blanching and infrared heating

Mild heat treatment of carrot slices as a pre-treatment for frozen storage was accomplished by exposure of slices to radiant heat to maximise thermal exposure of the cells at the surface while preserving the integrity of cells within the slices. Cell damage as a consequence of this treatment on texture was evaluated. Carrot slices treated for 7 s with radiant energy in the far-infrared region from

Conflict Prevention from a Nordic Perspective: Putting Prevention into Practice

Since conflict prevention is a visionary strategy it has beer difficult to put it into practice. This article explores conflict prevention in practice as well as in theory. There have been several attempts by the international community to take a proactive rather than a reactive approach to conflict management. One case often held up as a model for post Cold War prevention is the preventive missio

Well-posedness, blowup, and global existence for an integrable shallow water equation

We establish the local well-posedness for a recently derived model that combines the linear dispersion of Korteweg-de Veris equation with the nonlinear/nonlocal dispersion of the Camassa-Holm equation, and we prove that the equation has solutions that exist for indefinite times as well as solutions that blow up in finite time. We also derive an explosion criterion for the equation, and we give a s

Core-level spectroscopy study of the Li/Si(111)-3 x 1, Na/Si(111)-3 x 1, and K/Si(111)-3 x 1 surfaces

In this article we report Si 2p core-level spectroscopy results from the alkali (Li, Na, and K) induced Si(111)-3 x 1 reconstructions. The experimental results are compared to the theoretical honeycomb-chain channel (HCC) model for,the 3 x 1 reconstruction using density functional theory (DFT) to calculate core-level shifts using both initial and final-state calculation schemes. Si 2p core-level s

Occupational exposure to hexahydrophthalic anhydride: air analysis, percutaneous absorption, and biological monitoring

Urinary hexahydrophthalic acid (HHP acid) levels were determined in 20 workers occupationally exposed to hexahydrophthalic anhydride (HHPA) air levels of 11-220 micrograms/m3. The levels of HHP acid in urine increased rapidly during exposure and the decreases were also rapid after the end of exposure. The elimination half-time of HHP acid was 5 h, which was significantly longer than in experimenta

New antimicrobial peptide active against Gram-positive pathogens

Background & objectives: Human and animal cystatins have been shown to inhibit the replication of certain viruses and bacteria, though it is not directly demonstrated that the effects are due to protease inhibitory capacity of the cystatins. We report antibacterial properties of a novel antimicrobial peptidyl derivative, (2S)-2-(N-alpha-benzyloxycarbonyl-arginyl-leucylamido)-1-(E)-cinnamoyla m

Ecological implications of the production of toxic substances by fish killing phytoplankton species grown under variable N:P-ratios

The influence of different nutrient conditions on the production of toxins was studied in certain fishkilling haptophytes (e.g. Prymnesium parvum and Chrysochromulina polylepis). The toxicity was strongly influenced by the nutrient status of the medium, resulting in a significantly higher toxicity when grown under nutrient limited conditions compared to nutrient replete conditions. This occurred i

Aquaporin-1 plays an essential role in water permeability and ultrafiltration during peritoneal dialysis

The water channel aquaporin-1 (AQP1) is considered as the molecular counterpart of the ultrasmall pore predicted by the three-pore model of fluid transport across the peritoneal membrane. However, the definitive proof of the implication of AQP1 in solute-free water transport, sodium sieving, and ultrafiltration (UF) during peritoneal dialysis (PD) is lacking, and the effects of its deletion on the

Demonstrating the Performance and Emission Characteristics of a Variable Compression Ratio, Alvar-Cycle Engine

This paper is a direct continuation of a previous study that addressed the performance and design of a variable compression engine, the Alvar-Cycle Engine [1]. The earlier study was presented at the SAE International Conference and Exposition in Detroit during February 23- 26, 1998 as SAE paper 981027. In the present paper test results from a single cylinder prototype are reviewed and compared wit