Column experiments to assess the effects of electron donors on the efficiency of in situ precipitation of Zn, Cd, Co and Ni in contaminated groundwater applying the biological sulfate removal technology.

Background, Aims And Scope: In a previous study, we explored the use of acetate, lactate, molasses, Hydrogen Release Compound (HRC, which is based on a biodegradable poly-lactate ester), methanol and ethanol as carbon source and electron donor to promote bacterial sulfate reduction in batch experiments, this with regards to applying an in situ metal precipitation (ISMP) process as a remediation tool to treat heavy metal contaminated groundwater at the site of a nonferrous metal work company. Based on the results of these batch tests, column experiments were conducted with lactate, molasses and HRCI as the next step in our preliminary study for a go-no go decision for dimensioning an on site application of the ISMP process that applies the activity of the endogenous population of sulfate-reducing bacteria (SRB). Special attention was given to the sustainability of the metal precipitation process under circumstances of changing chemical oxygen demand (COD) to [SO4(2-)] ratios or disrupted substrate supply.

House dust as possible route of environmental exposure to cadmium and lead in the adult general population.

Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of > or = 3 mg/kg (n=268) and a reference area (n=205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants' bedrooms.

The band 12 issue in the electron momentum spectra of norbornane: a comparison with additional Green's Function calculations and ultraviolet photoemission measurements.

In continuation of a recent study of the electronic structure of norbornane [J. Chem. Phys.

A version of the EM algorithm for proportional hazard model with random effects.

Proportional hazard models with multivariate random effects (frailties) acting multiplicatively on the baseline hazard have recently become a topic of an intensive research. One of the main practical problems related to the models is the estimation of parameters. To this aim, several approaches based on the EM algorithm have been proposed.

The structural proteome of Pseudomonas aeruginosa bacteriophage phiKMV.

The structural proteome of phiKMV, a lytic bacteriophage infecting Pseudomonas aeruginosa, was analysed using two approaches. In one approach, structural proteins of the phage were fractionated by SDS-PAGE for identification by liquid chromatography-mass spectrometry (LC-MS). In a second approach, a whole-phage shotgun analysis (WSA) was applied.

Changes in Permeability of Brush Border Membrane Vesicles from Spodoptera littoralis Midgut Induced by Insecticidal Crystal Proteins from Bacillus thuringiensis.

Bacillus thuringiensis insecticidal crystal proteins (ICPs) are thought to induce pore formation in midgut cell membranes of susceptible insects. Cry1Ca, which is significantly active in Spodoptera littoralis, made brush border membrane vesicles permeable to KCl (osmotic swelling was monitored by the light scattering technique); the marginally active ICPs Cry1Aa, Cry1Ab, and Cry1Ac did not.

Direct likelihood analysis versus simple forms of imputation for missing data in randomized clinical trials.

Background: In many clinical trials, data are collected longitudinally over time. In such studies, missingness, in particular dropout, is an often encountered phenomenon.

Methods: We discuss commonly used but often problematic methods such as complete case analysis and last observation carried forward and contrast them with broadly valid and easy to implement direct-likelihood methods.

Modelling age-dependent force of infection from prevalence data using fractional polynomials.

The force of infection is one of the primary epidemiological parameters of infectious diseases. For many infectious diseases it is assumed that the force of infection is age-dependent. Although the force of infection can be estimated directly from a follow up study, it is much more common to have cross-sectional seroprevalence data from which the prevalence and the force of infection can be estimated.

Impaired activation-induced telomerase activity in PBMC of early but not chronic rheumatoid arthritis patients.

Although telomerase activity is important in normal immune function, it is unclear whether telomerase or telomerase (dys)regulation plays a role in the pathogenic immune response in autoimmune diseases like rheumatoid arthritis (RA). In this study, we evaluated the dynamics of the activation-induced human telomerase reverse transcriptase (hTERT) response in RA patients and non-RA controls. The expression of the catalytic subunit of telomerase, hTERT, was measured in peripheral blood mononuclear cells (PBMC) of RA patients and controls after in vitro stimulation with anti-CD3 monoclonal antibody (mAb) using real-time PCR.

Premature immunosenescence in rheumatoid arthritis and multiple sclerosis patients.

Patients with T-cell-mediated autoimmune diseases show immune system abnormalities that resemble the typical characteristics of autoimmune dysfunction described in the elderly. In addition, the incidence of autoimmune disease increases with advancing age. To evaluate whether patients with rheumatoid arthritis (RA) and multiple sclerosis (MS) have premature immuno-senescence, we measured two indicators of aging: the number of T-cell-receptor excision circles (TRECs) and the percentage of CD4+CD28(null) T cells.

Design and analysis of drug combination experiments.

In this paper we present and discuss a novel, simple and easy to implement parametric modeling approach to assess synergy. An extended three parameter log-logistic model is used to analyse the data and calculate confidence intervals of the interaction indices. In addition the model corrects for the bias due to plate-location effects.

Behavioral testing of antidepressant compounds: an analysis of crossover design for correlated binary data.

The differential reinforcement of low-rate 72 seconds schedule (DRL-72) is a standard behavioral test procedure for screening potential antidepressant compounds. The protocol for the DRL-72 experiment, proposed by Evenden et al. (1993), consists of using a crossover design for the experiment and one-way ANOVA for the statistical analysis.

Again, what the philosophy of biology is not.

There are many things that philosophy of biology might be. But, given the existence of a professional philosophy of biology that is arguably a progressive research program and, as such, unrivaled, it makes sense to define philosophy of biology more narrowly than the totality of intersecting concerns biologists and philosophers (let alone other scholars) might have. The reasons for the success of the "new" philosophy of biology remain poorly understood.

Review of guidelines for testing and treatment of osteoporosis.

Our knowledge on diagnosis and treatment of osteoporosis has steadily increased during the past decade. Several guidelines on treatment of osteoporosis are now available. Although there is heterogeneity in these recommendations, there are several common suggestions found.

Pitfalls and their remedies in time-resolved fluorescence spectroscopy and microscopy.

Time-resolved fluorescence spectroscopy and microscopy in both time and frequency domains provide very useful and accurate information on dynamic processes. Good quality data are essential in obtaining reliable parameter estimates. Distortions of the fluorescence response due to artifacts may have disastrous consequences.

Analysis of bean (Phaseolus vulgaris L.) proteins affected by copper stress.

The effect of excess copper on the expression of soluble proteins in 10-day old Phaseolus vulgaris seedlings was studied with two-dimensional electrophoresis and mass spectrometry, to find sensitive biochemical markers of exposure. Despite major differences in root Cu contents, both 15 and 50 microM Cu treatments resulted in equal enhancements of Cu in the primary leaves. Three proteins, apparently reacting in a dose-dependent manner to Cu exposure, were identified from roots.

Understanding spatial concentrations of road accidents using frequent item sets.

This paper aims at understanding why road accidents tend to cluster in specific road segments. More particularly, it aims at analyzing which are the characteristics of the accidents occurring in "black" zones compared to those scattered all over the road. A technique of frequent item sets (data mining) is applied for automatically identifying accident circumstances that frequently occur together, for accidents located in and outside "black" zones.

Peripheral blood but not synovial fluid natural killer T cells are biased towards a Th1-like phenotype in rheumatoid arthritis.

Natural killer T (NKT) cells have been implicated in the regulatory immune mechanisms that control autoimmunity. However, their precise role in the pathogenesis of rheumatoid arthritis (RA) remains unclear. The frequency, cytokine profile and heterogeneity of NKT cells were studied in peripheral blood mononuclear cells (PBMCs) from 23 RA patients and 22 healthy control individuals, including paired PBMC-synovial fluid samples from seven and paired PBMC-synovial tissue samples from four RA patients.

Induction of oxidative stress and antioxidative mechanisms in Phaseolus vulgaris after Cd application.

Oxidative stress has been shown to be of great importance in the toxicity of several metals (copper, zinc, ...

A hierarchical Binomial-Poisson model for the analysis of a crossover design for correlated binary data when the number of trials is dose-dependent.

The differential reinforcement of a low-rate 72-seconds schedule (DRL-72) is a standard behavioral test procedure for screening a potential antidepressant compound. The data analyzed in the article are binary outcomes from a crossover design for such an experiment. Recently, Shkedy et al.

Modeling anti-KLH ELISA data using two-stage and mixed effects models in support of immunotoxicological studies.

During preclinical drug development, the immune system is specifically evaluated after prolonged treatment with drug candidates, because the immune system may be an important target system. The response of antibodies against a T-cell-dependent antigen is recommenced by the FDA and EMEA for the evaluation of immunosuppression/enhancement. For that reason, we developed a semiquantitative enzyme-linked immunosorbent assay to measure antibodies against keyhole limpet hemocyanin.

Parity-induced changes in global gene expression in the human mammary gland.

The protective effect of an early first full-term pregnancy in relation to breast cancer risk is well established, but the molecular and cell-specific changes in the human mammary gland involved remain unclear. To identify the molecular changes associated with pregnancy-induced differentiation, we analysed the global gene expression profiles of normal mammary tissues from both a parous and a nulliparous woman, using serial analysis of gene expression. This approach allowed us to identify sets of genes, known and unknown, that are differentially expressed in parous versus age-matched nulliparous mammary gland tissues.

Impedimetric immunosensors based on the conjugated polymer PPV.

In the work reported here, we investigated the interaction between the semiconducting polymer MDMO-PPV and antibodies against the fluorescent dyes fluorescein isothiocyanate (FITC) and Cy5. The antibodies are adsorbed physically onto thin polymer films on gold electrodes, as seen in AFM images of these films. By tuning the antibody concentration, the contact angle of distilled water with the film can be made to vary between 95 degrees and 50 degrees, showing that different surface densities of antibody can be obtained.

Biometry, biometrics, biostatistics, bioinformatics,..., bio-X.

Recent scientific evolutions force us to rethink our profession's position on the scientific map, in relation to our neighboring professions, the ones with which we traditionally have strong collaborative links as well as the newly emerging fields, but also within our own, diverse professional group. We will show that great inspiration can be drawn from our own history, in fact from the early days of the Society. A recent inspiring example has been set by the late Rob Kempton, who died suddenly just months before he was to become President of the International Biometric Society.

Immunohistochemical evidence for proteolipid protein and nestin expression in the late bell stage of developing rodent teeth.

In this study, the expression of proteolipid protein (PLP) and nestin is studied in the late bell stage of developing rodent teeth in neonatal rats. By using immunohistochemistry, it was shown that odontoblasts, ameloblasts and the stratum intermedium are positive for PLP in regions of active matrix deposition. Reactivity for nestin could be detected in the odontoblasts, stratum intermedium and in some of the apical processes of the ameloblasts.