A sustainable approach toward mechanical recycling unsortable post-consumer WEEE: Reactive and non-reactive compatibilization

While near-infrared (NIR) spectroscopy in post-consumer waste electrical and electronic equipment (WEEE) recycling accurately separates white or clear polymers, 40% containing dark plastics, termed 'unsortable WEEE,' are excluded from sorting lines and therefore incinerated or landfilled, causing environmental concerns. This study investigates the potential of using non-reactive and reactive copolymers as compatibilizers to enhance the performance of unsortable WEEE plastics free of brominated flame retardants. To the best of our knowledge, this is the first time that such copolymers have been explored as a solution for improving the compatibility of unsortable WEEE polymer blends. Initial trials with 4% of styrene-ethylene-butylene-styrene copolymer (SEBS-13) and SEBS-30-g-(maleic anhydride) copolymer (SEBS-30-g-MA MA) as compatibilizers showed insufficient results compared to virgin commercial polymers. However, the addition of higher concentrations of compatibilizers (i.e. up to 20 wt%) and the use of a SEBS having a higher styrene content (i.e. SEBS-30) improved the mechanical properties of the material, causing it to transition from brittle to ductile. This behavior was found more pronounced for the 20% non-reactive SEBS-30, for which the SEM analysis showed reduced phase segregation and revealed a more homogeneous fracture surface. This was further supported by Differential Scanning Calorimetry (DSC) analysis, which showed evidence of an interaction between one or more polymer phases. With a room temperature performance equivalent to that of virgin conventional polymers, the SEBS-30 compatibilization approach has made it possible to consider using unsortable WEEE streams as recycled materials in commercial applications.

The effect of metal ions on the viscoelastic properties of thermosensitive sol-to-gel reversible metallo-supramolecular hydrogels

Fine-tuning of thermo-induced assembly and rheological behaviour of hydrogels based on a copolymer having two distinct hydrophilic blocks via metal ions.

Physical Activity Is Associated with Attention Capacity in Adolescents

OBJECTIVE

To assess the relationships among physical activity, measured objectively, and attention capacity in European adolescents.

STUDY DESIGN

The study included 273 adolescents, aged 12.5-17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Participants wore a uniaxial accelerometer for 7 days to measure physical activity. The d2 Test of Attention was administered to assess attention capacity. Multivariate analyses were used to study the association of attention capacity with each measure of physical activity. Receiver operating characteristic analysis was performed to determine thresholds that best discriminate between low and good attention capacity.

RESULTS

After controlling for potential confounding variables (age, sex, body mass index, parental educational level, fat mass, aerobic fitness, and center), adolescents' attention capacity test performances were significantly and positively associated with longer time spent in moderate or moderate-to-vigorous physical activity (MVPA) in free-living conditions (P < .05). Receiver operating characteristic curve analyses revealed that the physical activity thresholds that best discriminated between low/good attention capacities were ≥41 min·day(-1) for moderate, ≥12 min·day(-1) for vigorous, and ≥58 min·day(-1) for MVPA.

CONCLUSION

These findings suggest that promoting MVPA may be have a beneficial effect on attention capacity, an important component of cognition, in adolescents.

Introducing the Azlactone Functionality into Polymers through Controlled Radical Polymerization: Strategies and Recent Developments

Polymers containing the highly reactive azlactone group have emerged as a powerful platform useful in various application areas. This Highlight summarizes recent developments in the field of azlactone-derived polymers made in our group using controlled radical polymerizations (ATRP and RAFT) and ‘click’ chemistry methodology (thiol-Michael addition), leading to well defined reactive polymers.

[Criminal court expert reports]

In relation with the structured pattern of crime today, and owing to the evolution observed among sciences and techniques, the legal system more and more frequently requires expert advice in numerous criminal cases with increasing technicality. The expert and the investigating officer appear to be of equal importance regarding the advices on which the judge bases both his evidence appreciation and his judgement when giving a ruling on a suspect's potential culpability.

Rgg proteins associated with internalized small hydrophobic peptides: a new quorum-sensing mechanism in streptococci

We identified a genetic context encoding a transcriptional regulator of the Rgg family and a small hydrophobic peptide (SHP) in nearly all streptococci and suggested that it may be involved in a new quorum-sensing mechanism, with SHP playing the role of a pheromone. Here, we provide further support for this hypothesis by constructing a phylogenetic tree of the Rgg and Rgg-like proteins from Gram-positive bacteria and by studying the shp/rgg1358 locus of Streptococcus thermophilus LMD-9. We identified the shp1358 gene as a target of Rgg1358, and used it to confirm the existence of the steps of a quorum-sensing mechanism including secretion, maturation and reimportation of the pheromone into the cell. We used surface plasmon resonance to demonstrate interaction between the pheromone and the regulatory protein and performed electrophoretic mobility shift assays to assess binding of the transcriptional regulator to the promoter regions of its target genes. The active form of the pheromone was identified by mass spectrometry. Our findings demonstrate that the shp/rgg1358 locus encodes two components of a novel quorum-sensing mechanism involving a transcriptional regulator of the Rgg family and a SHP pheromone that is detected and reimported into the cell by the Ami oligopeptide transporter.

Transcript quantification based on chemical labeling of RNA associated with fluorescent detection

A general method for RNA measurement, based on chemical labeling of RNA with digoxigenin (without retrotranscription), has been established. Labeled RNA is hybridized with nylon membranes containing spot blots of PCR-amplified gene fragments and the fluorescence detection is mediated via specific anti-digoxigenin antibody coupled to alkaline phosphatase. The method was optimized in order to be quantitative, and high precision (less than 24% error) was obtained, allowing analysis of relatively small changes in gene expression. When the quantity of cellular RNA used in this method is maintained constant and the amount of RNA in the cell determined, the true intracellular transcript concentrations can be determined, rather than simple abundance of a messenger in RNA population. This RNA quantification technique was extended to macroarrays blotted automatically and the validity of the method was tested by comparison with expression data obtained by Northern blotting.

Clinical characteristics of familial B-CLL in the National Cancer Institute Familial Registry

In an ongoing study, families with two or more living cases of B-CLL in first-degree relatives have been recruited through physician and self-referral. Since 1967, 28 kindreds with 73 cases of B-CLL have been enrolled within the National Cancer Institute (NCI) Familial B-CLL Registry. Medical, clinical, and demographic information have been obtained from private physicians, patient interview, hospital records, and death certificates. We used SEER Registry data to compare characteristics of sporadic B-CLL to familial B-CLL. The mean age at diagnosis was approximately 10 years younger among familial cases (57.9 +/- 12.1) than that observed in sporadic cases (70.1 +/- 11.9). A higher percentage of second primary tumors among familial CLL cases compared to reports in sporadic was also observed (16% vs. 8.8%). However, the transformation rate to non-Hodgkin's lymphoma does not appear to be different from that reported for sporadic cases. In conclusion, we observed some differences between familial and sporadic cases; whether any of these characteristics affect survival time or severity of disease is unknown. The study of families with multiple B-CLL cases will aid in delineating the genes and environmental factors that may play a role in the development of both forms of B-CLL.

Familial eosinophilia: clinical and laboratory results on a U.S. kindred

We describe a five-generation kindred with familial eosinophilia (FE; MIM131400), characterized by the occurrence of sustained eosinophilia of unidentifiable cause in multiple relatives. The inheritance pattern is consistent with an autosomal dominant pattern. Among 52 related subjects studied, 19 were affected and 33 were unaffected. Ten unaffected spouses were also evaluated. Four subjects with sustained eosinophilia were diagnosed with cardiac abnormalities and two of them also had neurologic symptoms. In comparison with the unaffected or spouses, evaluation of complete blood counts showed that the affected relatives had, as expected, significantly higher white cell (P < 0.005) and absolute eosinophil counts (P < 0.001) and lower red cell counts (P < 0.05). Evaluation of serum cytokine levels (IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GMCSF) and serology for parasitic helminth infection demonstrated no differences between the affected and unaffected individuals; no individuals studied had serologic evidence for parasitic infection. There were also no differences in anti-nuclear antibody, serum cobalamin (vitamin B12) level, immunoglobulin level, leukocyte alkaline phosphatase, rheumatoid factor, HLA analysis, and stool findings for ova and parasites. Among eight affected persons who had peripheral blood or bone marrow karyotype analysis, two carried the same chromosome abnormality, a pericentric inversion of chromosome 10, inv (10) (p11.2q21.2). A gene mapping study is currently underway to study the underlying genetic mechanism(s) of this syndrome.

Immigration and cultural policies: a bone of contention between the Province of Quebec and the Canadian federal government

"This article addresses the way in which the Province of Quebec has obtained increasing power in the area of immigration.... Data from interviews with key members of [the Ministry of Immigration] and from selected documents are drawn on to illustrate Quebec's cultural politics. The Quebec position on the question of immigration as it has evolved in the context of immigration policies defined by the federal government in Ottawa is examined.... In particular, the present article considers how attempts to construct a cultural identity and a nation-state in Quebec have had important consequences for immigration policy and for attitudes and policies concerning Quebec's cultural minorities. The emergence of the notion of 'cultural communities' as a result of the constitutional rivalry and the on-going struggle for legitimacy between Quebec and Ottawa is also explored."

Ceftriaxone protects against tobramycin nephrotoxicity

The effect of ceftriaxone on tobramycin-induced nephrotoxicity was investigated. Female Sprague-Dawley rats were treated during 4 and 10 days with saline (NaCl, 0.9%), ceftriaxone at a dose of 100 mg/kg of body weight/12 h subcutaneously, tobramycin at doses of 40 and 60 mg/kg/12 h intraperitoneally, or the combination ceftriaxone-tobramycin. Creatinine levels in serum were significantly higher in animals treated with tobramycin alone given at 60 mg/kg/12 h during 10 days, compared with control animals (P < 0.01) or animals receiving the combination tobramycin-ceftriaxone (P < 0.01). After 10 days of treatment, ceftriaxone did not accumulate in renal tissue but did reduce the renal intracortical accumulation of tobramycin (P < 0.05). Tobramycin given alone at either 40 or 60 mg/kg/12 h induced a significant inhibition of sphingomyelinase activity compared with control animals (P < 0.05). However, this enzyme activity was significantly less inhibited when tobramycin was injected in combination with ceftriaxone (P < 0.05). Ceftriaxone alone had no effect on the activity of this enzyme. The [3H]thymidine incorporation into the DNA of renal cortex was also significantly lower in animals treated with tobramycin-ceftriaxone compared with animals receiving tobramycin alone (P < 0.05). The 24-h urinary excretion of beta-galactosidase was significantly reduced in animals treated with the combination tobramycin-ceftriaxone compared with the administration of tobramycin alone at 40 and 60 mg/kg/12 h after 5 and 10 days (P < 0.05). Histologically, ceftriazone induced very few cellular alterations and reduced considerably the presence of typical signs of tobramycin nephrotoxicity. This investigation demonstrated that ceftriaxone protects animals against tobramycin-induced nephrotoxicity.

Assessment of contractility changes in humans by transoesophageal echocardiography: the peak-systolic pressure end-systolic diameter relationship (PSPESDRS)

The peak-systolic pressure end-systolic diameter relationship (PSPESDRS) was determined in ten healthy subjects under general anaesthesia by using the radial artery pressure tracing (peak-systolic pressure) and transoesophageal 2d-and m-mode echocardiography (left ventricular diameters) without blocking of autonomic reflexes. Left ventricular load was changed by injection of a single intravenous dose of 0.2 mg nitroglycerin (NTG). Linear regression analysis showed a close linear relationship during the pressure decrease between peak-systolic pressures and end-systolic diameters. During infusion of dobutamine 5 micrograms/kg/min there was also a close linear relationship during pressure decrease with increased slope and unchanged Do (D0 = diameter at theoretical pressure zero). Values taken during pressure returning to control level were shifted leftward indicating transient increased contractility. We conclude, that the PSPESDRS can reliably be measured in humans without autonomic blockade during the decrease of arterial pressure after NTG, where reflex changes in inotropy are not yet present. This relationship increases in slope with dobutamine, reflecting the increased contractile state.

[Comparative echocardiographic studies on the negative inotropic effect of halothane, enflurane and isoflurane]

Using the afterload-independent end-systolic pressure-dimension-relationship a study was performed in order to investigate whether there are differences in the negative inotropic effects of halothane, enflurane and isoflurane at 1 MAC in 70% N2O. 30 patients of ASA-groups I and II were studied. Using transoesophageal 2d- and m-mode echocardiography the end-systolic-pressure-dimension-relationship was established and the slope (parameter of contractility) determined. The slope decreased significantly (paired Wilcoxon-test 2 alpha less than 0.01) with halothane (68.5/46.5 mmHg/cm), enflurane (56/48 mm Hg/cm) and isoflurane (63/35 mmHg/cm). There is no difference between the three groups (Kruskal-Wallis-test 2 alpha greater than 0.05). The negative inotropic effects of halothane, enflurane and isoflurane at 1 MAC in 70% N2O are the same. The vasodilation caused by isoflurane enables better pump function compared to halothane and enflurane, but may cause severe hypotension. We conclude that for cardiac risk patients isoflurane has no outstanding advantages in comparison to halothane and enflurane.