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Lunar dust: A negative control for biomarker analyses of extraterrestrial samples?

The purpose of this study was to assess, for the first time, the presence of muramic acid (Mur) and 3-hydroxy fatty acids (3-OH FAs), chemical markers for terrestrial bacteria in "curated" lunar samples by use of state-of-the-art gas chromatography-tandem mass spectrometry. The Apollo lunar sample collection has been stored, under isolation conditions, at the Johnson Space Center since 1969. Marke

Simulation of the condensate treatment process in a Kraft pulp mill

A simulation program has been developed and used to study the condensate treatment process in a kraft pulp mill consisting of a stripper, a methanol column and a decanter. The simulations require rigorous models for vapor-liquid and liquid-liquid equilibrium calculations. The Wilson equation and the NRTL equation (non random two liquids) have been used for these calculations New data were included

Not seeing the forest for the trees? The environmental effectiveness of forest certification in Sweden

Forest certification can be conceived as one of many rapidly growing non-state market driven (NSMD) modes of governance. The environmental effectiveness of forest certification is oftentimes evaluated by indicators such as stringency of standards, degree of participation by key stakeholders, certified area, etc. In political science, forest certification as an NSMD governance arrangement is usuall

Improved segmentation of deep brain grey matter structures using magnetization transfer (MT) parameter maps

Basal ganglia and brain stem nuclei are involved in the pathophysiology of various neurological and neuropsychiatric disorders. Currently available structural T1-weighted (T1w) magnetic resonance images do not provide sufficient contrast for reliable automated segmentation of various subcortical grey matter structures. We use a novel, semi-quantitative magnetization transfer (MT) imaging protocol

Signal sequence directs localized secretion of bacterial surface proteins.

All living cells require specific mechanisms that target proteins to the cell surface. In eukaryotes, the first part of this process involves recognition in the endoplasmic reticulum of amino-terminal signal sequences and translocation through Sec translocons, whereas subsequent targeting to different surface locations is promoted by internal sorting signals(1). In bacteria, N-terminal signal sequ

Altered cytoplasmic-to-nuclear ratio of survivin is a prognostic indicator in breast cancer

Purpose: Survivin (BIRC5) is a promising tumor biomarker. Conflicting data exist on its prognostic effect in breast cancer. These data may at least be partly due to the manual interpretation of immunohistochemical staining, especially as survivin can be located in both the nucleus and cytoplasm. Quantitative determination of survivin expression using image analysis offers the opportunity to develo

Pain relief after esophagectomy: Thoracic epidural analgesia is better than parenteral opioids

OBJECTIVE: To compare postoperative pain relief and pulmonary function in patients after thoracoabdominal esophagectomy treated by continuing perioperative thoracic epidural anesthesia or changing to parenteral opioids. DESIGN: Prospective, randomized study. SETTING: University teaching hospital. PARTICIPANTS: Thirty-three patients undergoing thoracoabdominal esophagectomy. INTERVENTIONS: General

Nurses' assessments and patients' perceptions: development of the night nursing care instrument (NNCI), measuring nursing care at night

Background: Nursing care provided at night has a different purpose and objective to that provided during the day. A review of the literature does not reveal any scientifically tested research instruments for evaluating and comparing the nurse's assessment of nursing care with the patient's perception at night. Aims and objectives: The aim of this study was to develop and test an instrument for eva

Seizure suppression in kindling epilepsy by intracerebral implants of GABA- but not by noradrenaline-releasing polymer matrices

Gamma-aminobutyric acid (GABA)-releasing polymer matrices were implanted bilaterally, immediately dorsal to the substantia nigra, in rats previously kindled in the amygdala. Two days after implantation, rats with GABA-releasing matrices exhibited only focal limbic seizures in response to electrical stimulation, whereas animals with control matrices devoid of GABA had generalized convulsions. GABA

Polychlorinated biphenyl load, aryl hydrocarbon receptor, and cytochrome P4501A1 induction in a wild population of Atlantic salmon (Salmo salar) from the Baltic Sea

The toxicity induced by several environmental pollutants is mediated by the aryl hydrocarbon receptor (AHR), which controls the expression of many biotransformation genes, such as cytochrome P4501A1 (CYP1A1). Previous studies have indicated that fish populations can evolve tolerance to persistent chlorinated pollutants by down-regulating the AHR pathway. Here, we measure to what extent tissue load

Impact of transposable elements on the evolution of mammalian gene regulation.

Transposable elements (TEs) are present in all organisms and nearly half of the human and mouse genome is derived from ancient transpositions. This fact alone suggests that TEs have played a major role in genome organization and evolution. Studies undertaken over the last two decades or so clearly show that TEs of various kinds have played an important role in organism evolution. Here we review th

Transhepatic intravascular ultrasound for evaluation of portal venous involvement in patients with cancer of the pancreatic head region.

The aim of this study was to evaluate the ability of intravascular ultrasound to diagnose tumor involvement of the portal and the superior mesenteric veins using the preoperative percutaneous, transhepatic approach, and to compare the findings with those made at concomitant direct portography, surgery, and histopathological examination. Ten patients with a preoperative diagnosis of a resectable tu

Wound contamination in cardiac surgery

Objectives: To investigate the degree of bacterial contamination in the sternal wound during cardiac surgery and the sternal skin flora after operation in order to increase our understanding of the pathogenesis of sternal wound infections. Design: Prospective study where cultures were taken peri- and postoperatively from sternal wounds and skin. Setting: University Hospital. Patients: 201 cardiac

The Fy(x) phenotype is associated with a missense mutation in the Fy(b) allele predicting Arg89Cys in the Duffy glycoprotein

The molecular basis of the three major alleles (Fy(a)/Fy(b)/Fy) of the Duffy (FY) blood group system has recently been established but the Fy(x) phenotype associated with weak expression of the Fy(b) and other FY antigens is poorly understood. In the Fy(x) genes of five unrelated British and Swedish donors with the Fy(a+b+weak) phenotype we found two missense mutations predicting amino acid change

A Hamiltonian formulation of water waves with constant vorticity

We show that the governing equations for two-dimensional water waves with constant vorticity can be formulated as a canonical Hamiltonian system, in which one of the canonical variables is the surface elevation. This generalizes the well-known formulation due to Zakharov [32] in the irrotational case.

Risk of invasive cervical cancer in relation to management of abnormal Pap smear results

OBJECTIVE: We sought to evaluate the management of women with abnormal cytology in terms of subsequent risk of invasive cervical cancer. STUDY DESIGN: The screening histories of all invasive cervical cancer cases diagnosed in Sweden 1999-2001 and of 5 population-based controls per case were reviewed. In all, 159 patients and 258 control subjects aged < 67 years had an abnormal smear result 0.5-6.5