Assessment of baseline ecotoxicity of sediments from a prospective mining area enriched in light rare earth elements

Rare earth elements (REEs) disperse from indigenous rocks to the environment, thus making sediments one of the major sinks and sources of metal pollution. The emerging use of REEs and the subsequent opening of new mining areas may contribute to their release into surrounding ecosystems. For this reason, this study was performed in a natural area with geological material abundant in ferrocarbonatites and light REE. The aim of this work was to assess the natural REE availability and (eco)toxicity in freshwater sediments. Sediments showed high REE concentrations in samples with fine grain size fractions, and low in organic-rich sediments. The enrichment in LREE was mostly from rocks and the obtained enrichment factors (EF) confirmed that the sediments are not anthropogenically polluted. To assess REE availability and ecotoxicity, four toxicity tests were performed. REEs measured as the dissolved concentration in the test media were very low compared to the potentially available total REE in sediments and showed positive or negative correlations with fine or coarse grain sizes, respectively, and positive correlations with the content in Mg, Fe and Al. In tests performed in media supplemented with salts, the availability of REEs decreased considerably. Only some toxic effects could be linked to the REE contents in the ostracodtox and luminotox tests. However, measurement of toxicity could be influenced by the sediment properties and lead to a potential overestimation of ecotoxicity if only REE are regarded. Our study reveals that the physicochemical properties of sediments are a key factor controlling both REE availability and toxicity, whereas the determination of REE effects from toxicity tests using liquid media with salt addition will decrease REE availability and could mask toxic effects. Our findings provide new knowledge about REE behaviour in sediments and are a starting point for understanding potential REE pollution around prospective mining areas.

Comparison of two low-density lipoprotein apheresis systems in patients with homozygous familial hypercholesterolemia

Low-density lipoprotein (LDL) apheresis (LA) is a reliable method to decrease LDL-C concentrations and remains the gold standard therapy in homozygous familial hypercholesterolemia (HoFH). The objective of this study was to compare the efficacy of two LA systems [heparin-induced extracorporeal LDL precipitation (HELP) vs. dextran sulfate adsorption (DS) on the reduction of lipids, inflammatory markers, and adhesion molecules in a sample of genetically defined HoFH subjects (n = 9)]. Fasting blood samples were collected before and after LA. All subjects served as their own control and were first treated with the HELP system then with DS in this single sequence study. Compared with HELP, DS led to significantly greater reductions in total cholesterol (-63.3% vs. -59.9%; P = 0.05), LDL-C (-70.5% vs. -63.0%; P = 0.02), CRP (-75.3% vs. -48.8%; P < 0.0001), and TNF-α (-23.7% vs. +14.7%; P = 0.003). Reductions in the plasma levels of PCSK9 (-45.3% vs. -63.4%; P = 0.31), lipoprotein (a) (-70.6% vs. -65.0%; P = 0.30), E-selectin (-16.6% vs. -18.3%; P = 0.65), ICAM-1 (-4.0 vs. 5.6%; P = 0.56), and VCAM-1 (8.3% vs. -1.8%; P = 0.08) were not different between the two systems. For the same volume of filtered plasma (3,000 mL), however, HELP led to greater reductions in plasma apoB (-63.1% vs. -58.3%; P = 0.04), HDL-C (-20.6% vs. -6.5%; P = 0.003), and PCSK9 (-63.4% vs. -28.5%; P = 0.02) levels. These results suggest that both LA systems are effective in reducing plasma lipids and inflammatory markers in HoFH. Compared with HELP, greater reductions in lipid levels and inflammatory markers were achieved with DS, most likely because this method allows for a larger plasma volume to be filtered. J. Clin. Apheresis 31:359-367, 2016. © 2015 Wiley Periodicals, Inc.

Genotoxic impact of a municipal effluent dispersion plume in the freshwater mussel Elliptio complanata: an in situ study

Not available

Moderators of psychological recovery from benign cancer screening results

OBJECTIVE

The sudden confrontation of a potential health threat such as cancer, even after the diagnosis turns out to be benign, can have enduring adverse psychological consequences, including persistent anxiety, cancer fears, and other manifestations of psychological distress. The present study examines factors that potentially moderate psychological recovery among women who face a breast cancer threat.

DESIGN

Participants were adult women had just received a benign outcome from a breast cancer diagnostic procedure that had been conducted because of suspicion of breast cancer (a non-conclusive mammography or ultrasonography result, a referral from their doctor because of pain or family history, detection of a lump, a 6-month follow-up appointment after a breast abnormality from a previous screening or diagnostic procedure, or a fluid leak from one or both breasts). We measured several psychological traits at Time 1 (right after receipt of the "no cancer" feedback) and then each month for the next 3 months. Analyses examined the factors that hindered or facilitated psychological recovery from the cancer threat.

RESULTS

Results showed that trait anxiety and family history of cancer hindered recovery and that older age and optimism facilitated recovery and lessened adverse psychological consequences. Self-regulatory strategies such as planful problem-solving, positive reappraisal, and mastery facilitated recovery.

CONCLUSIONS

Our findings shed light on the factors that are implicated in psychological recovery from a benign breast cancer outcome after a diagnostic procedure (ultrasonography, repeat or initial mammography, stereotactic biopsy, fine-needle aspiration, or ultrasound-guided biopsy). Those factors could be used to identify women who may experience prolonged psychological distress, so as to assist them when they face stressful diagnostic concerns.

A descriptive study of a specialized worker's psychological trauma program

BACKGROUND

Psychological trauma in the workplace is gaining recognition as an important cause of workplace disability but little is known about the workers who are affected. The Psychological Trauma Program (PTP) in Toronto (Canada) is a specialized provincial worker's compensation board assessment program for workers with psychological sequelae of workplace trauma.

AIMS

To characterize workers presenting to the PTP in terms of demographic, occupational, traumatic exposure and diagnostic variables.

METHODS

A retrospective secondary analysis of all workers referred to the PTP for assessment within 1 year of traumatic event between 1999 and 2006.

RESULTS

Five hundred and thiry-one referred workers were included in the study. Most workers were working-age male (76%), married (65%) and labourers (43%). Nearly half were born outside Canada. Post-traumatic stress disorder was the primary diagnosis in 44%. Fifty-eight percent had one or more secondary diagnoses. For just over half of the workers, the traumatic event resulted in a permanent physical impairment.

CONCLUSIONS

Specialist referral may be indicated for workers experiencing prolonged recovery following workplace trauma. Male workers and those with co-morbidities or permanent injuries may be more likely to require referral. Individualized treatment approaches are likely important; however, more research is needed to guide future interventions.

Atomic layer deposition of ZnS nanotubes

We report on the growth of high-aspect-ratio (approximately > 300) zinc sulfide nanotubes with variable, precisely tunable, wall thicknesses and tube diameters into highly ordered pores of anodic alumina templates by atomic layer deposition (ALD) at temperatures as low as 75 degrees C. Various characterization techniques are employed to gain information on the composition, morphology and crystal structure of the synthesized samples. Besides practical applications, the ALD-grown tubes could be envisaged as model systems for the study of a certain class of size-dependent quantum and classical phenomena.

The responsiveness of three-dimensional knee accelerations used as an estimation of knee instability and loading transmission during gait in osteoarthritis patient's follow-up

OBJECTIVE

Knee instability and joint loading transmission are two important biomechanical factors in subjects with knee osteoarthritis (OA). However, the relationship between these factors in a rehabilitation treatment remains unclear. The purpose of this study is to determine the responsiveness of a new three-dimensional (3D) acceleration method used as an estimation of knee instability and joint loading transmission during gait in OA subjects after a rehabilitation treatment.

METHOD

Twenty-four subjects with medial knee OA were included in this study. They had clinical and gait evaluations before and after 12 weeks of treatment. 3D linear knee accelerations, quadriceps and hamstring isometric strength and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) pain were quantified, and compared between both evaluations. Nine asymptomatic subjects participated in this study for gait comparison.

RESULTS

A significant reduction of the anterior posterior (AP) knee acceleration peak (P=0.02) had been detected after the treatment. No difference for both distal and lateral knee accelerations peak was found. A significant increase in quadriceps (P<0.001) and hamstring (P=0.006) strength was seen after treatment. The WOMAC of pain had shown significant reduction after the treatment (P<0.001).

CONCLUSION

The present study demonstrates that the estimation of knee acceleration parameters is sensitive to changes in knee OA gait after a rehabilitation treatment. This study also indicates that a treatment of 3 months which combines therapeutic and exercises program could have benefits on knee OA by increasing AP knee stability and stabilize joint loading transmission during gait.

Comparison of respiratory rate estimation based on tracheal sounds versus a capnograph

The objective was to compare the accuracy of estimations of respiratory rate (RR), based on tracheal sounds, with simultaneous estimations from a capnograph, using as a common reference a pneumotachometer. Five subjects without pulmonary diseases were enrolled. Tracheal sounds were acquired using a contact piezoelectric sensor placed on the subject's throat and analyzed using a combined investigation of the sound envelope and frequency content. The capnograph and pneumotachometer were coupled to a face mask worn by the subjects. There was a strong linear correlation (r2= 0.98) between the acoustic method and the pneumotachometer and also between the capnograph and the pneumotachometer (r2 = 0.98). The SEE obtained by the acoustic method was 1.11 and the SEE obtained by the capnograph was 1.23. As a conclusion, the accuracy of the respiratory rate estimated from tracheal sounds on adult subjects was comparable to the accuracy of a commercial capnograph, using as a common reference a pneumotachometer.

Seeing is remembering: do deficits in closure affect visual memory recognition in schizophrenia?

INTRODUCTION

Episodic memory is significantly impaired in people with schizophrenia. The precise cause of this impairment has yet to be determined, as the formation of episodic memories is dependent on other processes, some of which also show impairment in schizophrenia. One such process is closure, that is, the filling-in of missing information. Failure to close adequately incomplete stimuli may cause people with schizophrenia to store inadequate or piecemeal representations in memory.

METHODS

Forty people with schizophrenia and 21 healthy comparison subjects participated in the study. The experiment was divided into six blocks, each of which involved both an encoding and a recognition phase. During the encoding phase, 20 figures were presented sequentially and participants had to determine whether each was symmetric or asymmetric. These figures were either complete or fragmented at three different levels. In subsequent recognition phase, 40 abstract figures (20 new and 20 old) were presented. All figures were complete in this phase.

RESULTS

Memory performance of both groups was affected similarly by fragmentation, with an additional increase in performance afforded by a slight fragmentation for participants with schizophrenia.

CONCLUSION

Slight fragmentation may have induced a perceptual difficulty that was mild enough to increase visual processing without compromising it. Closure was thus not involved in the episodic memory deficit of people with schizophrenia.

[Prefrontal dysfunction in schizophrenia: implication is associative recognition]

OBJECTIVE

We used an event related functional magnetic resonance imaging (fMRI) method to examine the neural basis of associative recognition memory deficit in schizophrenia.

METHODS

Fifteen people with schizophrenia and 18 healthy control subjects were scanned with fMRI while performing a memory task (coding and recognition) of visual objects. During coding, the subjects studied items and pairs of items. During recovery, the subjects had to recognize items (old/new decisions) and recognize associations (intact/rearranged decisions). The study design was based on a random effect model and the fMRI analysis was restricted to correct items only.

RESULTS

At the behavioral level, both groups performed equally well on item recognition, whereas people with schizophrenia demonstrated poorer performance on associative recognition. At the brain level, comparison between associative and item recognition tasks revealed greater left dorsolateral prefrontal and right inferior prefrontal activations in the control group relative to the schizophrenia group.

CONCLUSIONS

The findings of this fMRI study suggest the prefrontal cortex as the basis for the selective memory deficit for associative recognition observed in schizophrenia.

Estimation of tibial and femoral 3D linear accelerations during gait

Shock wave traveling through the skeletal are more and more considered in the development of articular disorders. A method to quantify those skeletal transients is to estimate body segment linear accelerations. However, linear accelerations magnitude is influenced by many factors such as location and fixation of sensors, walking velocity, walking level and also by wearing conditions. Hence, experimental results in literature can't be easily compared and normative data haven't been established yet. The present paper proposes a method to estimate three-dimensional (3D) tibial and femoral linear accelerations during treadmill walking. 15 able-bodied subjects were evaluated. 3D kinematics data recorded from an optoelectronic system (Optotrak 3010, Northern Digital, Canada) at knee joint level were derived to estimated 3D linear accelerations of the tibia and the femur at their respective coordinate system origins.