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Sea surface temperatures and ice rafting in the Holocene North Atlantic: climate influences on Northern Europe and Greenland

The oceanographic conditions in the high-latitude North Atlantic ocean during the Holocene were reconstructed through analyses of sea surface temperature (SST; alkenone unsaturation ratios) and ice rafting (mineralogy and grain size) from two sediment sequences, one recovered from the Reykjanes Ridge at 59degreesN and the other from the Norwegian Sea at 68degreesN. Comparison of our records to pub

Shielded and unshielded geometries in the search for orphan sources.

A car-borne NaI(TI) spectrometric system was used together with a Cs-137 source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting met

Performance measures of implant antennas

Modern electronic medical implants have reached a high degree of complexity. This has increased the demands on the communication link with the implant, both regarding the bandwidth and the communication distance. A medical communication system at RF frequencies has been standardised, the Medical Implant Communication System (MICS), which use a frequency allocation of 402 - 405 MHz. This frequency

Black box for constant-time insertion in priority queues

We present a simple black box that takes a priority queue Q which supports find-min, insert, and delete in x-time at most t. Here x-time may be worst-case, expected, or amortized. The black-box transforms Q into a priority queue Q* that supports find-min in constant time, insert in constant x-time, and delete in x-time O(t). Moreover, if Q supports dec-key in constant time, then so does Q*.

Gene delivery to adult neural stem cells

Neural stem cells may present an ideal route for gene therapy as well as offer new possibilities for the replacement of neurons lost to injury or disease. However, it has proved difficult to express ectopic genes in stem cells. We report methods to introduce genes into adult neural stem cells using viral and nonviral vectors in vitro and in vivo. Adenoviral and VSV-G-pseudotyped retroviral vectors

Nonionic polymers and surfactants: Temperature anomalies revisited

In view of a rapidly increasing importance in applications, as well as significant fundamental observations, the temperature anomalies displayed by several oxyethylene compounds, including poly(ethylene glycol), and oxyethylene surfactants and copolymers continue to create interest but also controversies. Here we review a wide range of experimental observations and present the different theoretica

Synthesis, in vitro, and in vivo evaluation of phosphate ester derivatives of combretastatin A-4

Combretastatin A-4 disodiumphosphate (CA4P), a prodrug formulation of the natural product combretastatin A-4 (CA4), is currently in clinical investigation for the treatment of cancer. In vivo, CA4P is rapidly enzymatically converted to CA4, a potent inhibitor of tubulin polymerization (IC50 = 1-2 muM), and rapidly causes bloodflow shutdown in tumor tissues. A variety of alkyl and aryl di- and trie

Meat intake and bladder cancer in a prospective study: a role for heterocyclic aromatic amines?

Objective The suspect carcinogens, heterocyclic amines (HAAs), found in well-done meat require host-mediated metabolic activation before inducing DNA mutations. The role of SULT1A1 and of NAT2 on the activation of HAAs suggests that NAT2 rapid acetylator genotype and SULT1A1 allele variants can have an effect on HAA carcinogenicity. Methods Data were collected as part of a case-control study neste

Classical nuclear motion in quantum transport

An ab initio quantum-classical mixed scheme for the time evolution of electrode-device-electrode systems is introduced to study nuclear dynamics in quantum transport. Two model systems are discussed to illustrate the method. Our results provide the first example of current-induced molecular desorption as obtained from a full time-dependent approach and suggest the use of ac biases as a way to tail

Structure and motion problems for multiple rigidly moving cameras

Vision (both using one-dimensional and two-dimensional retina) is useful for the autonomous navigation of vehicles. In this paper the case of a vehicle equipped with multiple cameras with non-overlapping views is considered. The geometry and algebra of such a moving platform of cameras are considered. In particular we formulate and solve structure and motion problems for a few novel cases of such

Survivors of acute leukaemia and highly malignant lymphoma - retrospective views of daily life problems during treatment and when in remission.

Fifty-four former patients, in remission after acute leukaemia or highly malignant lymphoma, responded to a questionnaire covering their physical problems, their view of the help they received, who was most helpful to them during the treatment phase, and the impact of the disease and treatment on their current life. Energy loss and nutritional problems were most troublesome during the treatment ph

Determination of surface normal temperature gradients using thermographic phosphors and filtered Rayleigh scattering

Wall temperature as well as the temperature distribution within or close-by the boundary layer of an electrically heated axisymmetric jet impinging on a flat plate were monitored to deduce wall-normal temperature gradients. The radial surface temperature profile of the plate was determined by coating it with thermographic phosphors (TPs), materials whose phosphorescence decay time is dependent on

Heparan sulfate proteoglycan as a plasma membrane carrier

The plasma membrane defines the border of living cells and provides a barrier to extracellular components. Advances in molecular biology have resulted in the development of novel therapeutic strategies (e.g. gene therapy and cellular protein delivery) which rely on the entry of charged macromolecules into the intracellular compartment. Recent reports demonstrate an intriguing role for heparan sulf

Surface properties of tetra(ethylene oxide) dodecyl amide compared with poly(ethylene oxide) surfactants. 1. Effect of the headgroup on adsorption

The surfactant tetra(ethylene oxide) n-dodecyl amide (TEDAd) was compared with the poly(ethylene oxide) n-alkyl ethers C12E5, C10E5, and C12E4. The adsorption to hydrophobic liquid-vapor and solid-liquid interfaces, as well as the wetting behavior on a hydrophobic surface, was investigated. The amide group is more hydrophilic than the ethylene oxide group, raising the cloud point and critical mice

Major role of human KLK14 in seminal clot liquefaction

Liquefaction of human semen involves proteolytic degradation of the seminal coagulum and release of motile spermatozoa. Several members of human kallikrein-related peptidases (KLKs) have been implicated in semen liquefaction, functioning through highly regulated proteolytic cascades. Among these, KLK3 (also known as prostate-specific antigen) is the main executor enzyme responsible for processing

Cost-effectiveness of tacrolimus ointment vs. standard treatment in patients with moderate and severe atopic dermatitis: a health-economic model simulation based on a patient survey and clinical trial data.

Background Atopic dermatitis (AD) affects health and quality of life (QoL) and also has great impact on both healthcare costs and costs to society. Objectives The aim of the study was to analyse the cost-effectiveness of treatment with tacrolimus ointment vs. standard treatment in patients with moderate to severe AD. Methods A Markov simulation model was constructed capturing several key features

Urinary diversion

A consensus conference convened by the World Health Organization (WHO) and the Societe Internationale d'Urologie (SIU) met to critically review reports of urinary diversion. The world literature on urinary diversion was identified through a Medline search. Evidence-based recommendations for urinary diversion were prepared with reference to a 4-point scale. Many level 3 and 4 citations, but very fe

Post inflammatory damage to the enteric nervous system in diverticular disease and its relationship to symptoms

Some patients with colonic diverticula suffer recurrent abdominal pain and exhibit visceral hypersensitivity, though the mechanism is unclear. Prior diverticulitis increases the risk of being symptomatic while experimental colitis in animals increases expression of neuropeptides within the enteric nervous system (ENS) which may mediate visceral hypersensitivity. Our aim was to determine the expres