Fractionation of platinum group elements in aqueous systems: comparative kinetics of palladium and platinum removal from seawater by Ulva lactuca L

A marine macroalga, Ulva lactuca L., was used as a substrate to compare the kinetics of palladium (Pd) and platinum (Pt) removal from seawater. This work indicates that, while the equilibrium behaviors of Pd and Pt are in many respects similar, their kinetic behaviors are quite distinct. The removal of both Pt(II) and Pt(IV) from seawater by U. lactuca is slower than the removal of Pd(II) by approximately an order of magnitude. Relative Pd and Pt removal rates are strongly influenced by system hydrodynamics. Under quiescent conditions, lambda(Pd)/lambda(Pt), the ratio of Pd and Pt removal rates, is 7 +/- 2, whereas under turbulent conditions lambda(Pd)/lambda(Pt) can be as large as 27. These observations suggest that the disparate kinetic behaviors of Pd and Pt may produce considerable differences in the environmental dispersion of these elements.     

Long-term follow-up of patients with acute myocarditis by magnetic resonance imaging

Magnetic resonance imaging (MRI) reveals cardiac signal intensity changes in patients with acute myocarditis; however, the natural history of these changes and their relationship to individual outcomes are unknown. The relationship of MRI findings to long-term outcome was studied by serial MRI studies in 16 patients with acute myocarditis who were followed for 30±4 (SE) months. Myocardial contrast enhancement was monitored using contrast-enhanced T1-weighted fast spin-echo images. Left ventricular ejection fraction was measured with gradient-echo sequences. Clinical symptoms were scored. The results were compared to a control group of 26 age-matched, healthy volunteers. Myocardial contrast enhancement, which was markedly increased in the early course of the disease, decreased at 4 weeks and remained within the normal range in most patients after 30 months. Contrast enhancement 4 weeks after onset of symptoms was predictive for the functional and clinical long-term outcome. Contrast-enhanced MRI may be a useful, noninvasive tool for long-term follow-up of patients with acute myocarditis. Furthermore, relatively early MRI findings may predict longer-term outcomes. Electronic Publication     

Thermodynamic Properties of Some Methylphosphonyl Dihalides From 15 to 335 °K

Measurements of the heat capacity of methylphosphonyl difluoride (CH₃POF₂), methyl phosphonyl dichloride (CH₃POCl₂), and methylphosphonyl chlorofluoride (CH₃POClF) were made from about 15 to 335 °K by means of an adiabatic calorimeter. These highly reactive and toxic substances were purified in a completely closed glass apparatus by combining slow crystallization and fractional melting procedures. The purities determined by the freezing-curve method are shown to be generally in agreement with those values obtained by the calorimetric method. From the results of the heat measurements, the triple-point temperature, heat of fusion, and their corresponding estimated uncertainties were found to be, respectively, 236.34±0.05 °K and 11,878±12 J/mole for CH₃POF₂, 306.14± 0.02 °K and 18,076±15 J/mole for CH₃POCl₂, and 250.70± 0.20 °K and 11,853±30 J/mole for CH₃POClF. Triple-point temperatures obtained by the freezing-curve method are in agreement with the above values. A table of smoothed values of heat capacity, enthalpy, enthalpy function, entropy, Gibbs free energy, and Gibbs free energy function from 0 to 335 °K was obtained from the data. The entropy and its corresponding estimated uncertainty for CH3POF2, CH3POCl2, and CH3POClF in their respective condensed phase at 298.15 °K and saturation pressure was found to be 208.3± 0.3, 164.8± 0.3, and 216.4± 0.4 J/deg mole, respectively. The entropies in the gaseous state at 298.15 °K and 1 atm pressure were found to be 312.7±3, 339.7±3, and 335.0±3 J/deg mole, respectively.     

Current perspectives on using linguistic and cultural factors in counseling the Hispanic client.

This review of the literature examines the role of language and culture in the mental health treatment of Hispanic clients. Several innovative approaches including the use of dichos and cuento therapy are described that incorporate linguistic and cultural traits in treatment. The article proposes that the assessment of such factors as language proficiency, level of acculturation, and the degree to which cultural expressions represent symptomatology should be considered in the development of an effective treatment plan. The process of acculturation is presented as a critical dimension influencing language, cultural beliefs, and mental health. Recommendations are made for future research on issues relating to the use of language switching and language mixing in therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiple uses of performance appraisal: Prevalence and correlates.

Performance appraisal is used in organizations for a variety of purposes. However, little empirical research has been conducted to determine (a) the extent to which performance appraisal is used for each of several purposes in industry, (b) the extent to which appraisal data may be used for multiple and possibly conflicting uses within the same organization, and (c) organizational correlates of these uses. A survey questionnaire designed to answer these questions was mailed to 243 members of Division 14 of the American Psychological Association who were employed in industry. A factor analysis of the 106 completed questionnaires indicated four general uses of information from performance appraisals. The use of performance appraisal to simultaneously make distinctions between and within individuals is common. Canonical correlation analyses indicated that organizational characteristics were significantly related to uses of performance appraisal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preparation and characterization of surface active erucic acid derivatives

Nonionic, cationic and anionic surfactants, derivatives ofcis-13-docosenoic acid (erucic acid), have been prepared and characterized, and their performance has been evaluated and compared with the corresponding derivatives of fatty acids with shorter alkyl chain length. Nonionic erucic acid ethoxylates give a solution behavior anticipated from the hydrophilic-lipophilic balance of the molecule; however, the increased molecular size as compared to ordinary surfactants results, e.g., in higher temperature stability of the surfactant aggregates. Anomalous solution behavior was found and investigated for anionic surfactants, triethanolammonium salts of erucic acid, and some shorter homologues. The effects are discussed in terms of the acid-base equilibria of the alkanolammonium counterion and the acid, together with effects due to the molecular size of the counterion.     

Carbon Fiber–Bismaleimide Composites Filled with Nickel‐Coated Single‐Walled Carbon Nanotubes for Lightning‐Strike Protection

Multifunctional carbon fiber composites are imperative for next‐generation lightweight aircraft structures. However, lightning‐strike protection is a feature that is lacking in many modern carbon fiber high‐temperature polymer systems, due to their high electrical resistivity. This work presents a study on processing, materials optimization, and property development of high‐temperature bismaleimide (BMI)–carbon fiber composites filled with nickel‐coated single‐walled carbon nanotubes (Ni‐SWNTs) based on three key factors: i) dispersion of Ni‐SWNTs, ii) their surface coverage on the carbon plies and, iii) the composite surface resistivity. Atomic force microscopy analysis revealed that coating purified SWNTs with nickel enabled improved dispersion which resulted in uniform surface coverage on the carbon plies. The electrical resistivity of the baseline composite system was reduced by ten orders of magnitude by the addition of 4 wt% Ni‐SWNTs (calculated with respect to the weight of a single carbon ply). Ni‐SWNT–filled composites showed a reduced amount of damage to simulated lightning strike compared to their unfilled counterparts, as indicated by the minimal carbon fiber pull‐out.     

Isolation of the retinoblastoma cDNA from the marine flatfish dab (Limanda limanda) and evidence of mutational alterations in liver tumors

We have isolated a dab (Limanda limanda) homologue of the human retinoblastoma (Rb) tumor suppressor gene. The L. limanda partial Rb cDNA encodes a partial predicted protein of 753 amino acids. DNA sequence analysis with other vertebrate Rb sequences demonstrates that the L. limanda Rb cDNA is highly conserved in regions of functional importance. The sequence reported herein, combined with the high degree of conservation observed in critical domains, has also facilitated an investigation of the molecular etiology of environmentally induced liver tumor samples in a feral fish species. Mutational alterations were detected in liver adenoma samples, also in apparently "normal" regions of liver samples dissected from fish displaying adenoma, but not in normal liver samples from otherwise healthy feral fish. These results are the first reporting the appearance of Rb mutations in wild-caught fish and suggest that the molecular etiology of fish cancer appears to involve Rb-implicated tumorigenesis. The ecotoxicological relevance of the Rb mutations in feral fish liver tumors, in terms of future genome instability and possible development of a genotoxicity biomarker, is discussed.     

The Presence of Blood–Brain Barrier Modulates the Response to Magnesium Salts in Human Brain Organoids

Magnesium (Mg) is fundamental in the brain, where it regulates metabolism and neurotransmission and protects against neuroinflammation. To obtain insights into the molecular basis of Mg action in the brain, we investigated the effects of Mg in human brain organoids, a revolutionary 3D model to study neurobiology and neuropathology. In particular, brain organoids derived from human induced pluripotent stem cells were cultured in the presence or in the absence of an in vitro-generated blood–brain barrier (BBB), and then exposed to 1 or 5 mM concentrations of inorganic and organic Mg salts (Mg sulphate (MgSO₄); Mg pidolate (MgPid)). We evaluated the modulation of NMDA and GABAergic receptors, and BDNF. Our data suggest that the presence of the BBB is essential for Mg to exert its effects on brain organoids, and that 5 mM of MgPid is more effective than MgSO₄ in increasing the levels of GABA receptors and BDNF, and decreasing those of NMDA receptor. These results might illuminate novel pathways explaining the neuroprotective role of Mg.     

Endosomally Localized RGLG-Type E3 RING-Finger Ligases Modulate Sorting of Ubiquitylation-Mimic PIN2

Intracellular sorting and the abundance of sessile plant plasma membrane proteins are imperative for sensing and responding to environmental inputs. A key determinant for inducing adjustments in protein localization and hence functionality is their reversible covalent modification by the small protein modifier ubiquitin, which is for example responsible for guiding proteins from the plasma membrane to endosomal compartments. This mode of membrane protein sorting control requires the catalytic activity of E3 ubiquitin ligases, amongst which members of the RING DOMAIN LIGASE (RGLG) family have been implicated in the formation of lysine 63-linked polyubiquitin chains, serving as a prime signal for endocytic vacuolar cargo sorting. Nevertheless, except from some indirect implications for such RGLG activity, no further evidence for their role in plasma membrane protein sorting has been provided so far. Here, by employing RGLG1 reporter proteins combined with assessment of plasma membrane protein localization in a rglg1 rglg2 loss-of-function mutant, we demonstrate a role for RGLGs in cargo trafficking between plasma membrane and endosomal compartments. Specifically, our findings unveil a requirement for RGLG1 association with endosomal sorting compartments for fundamental aspects of plant morphogenesis, underlining a vital importance for ubiquitylation-controlled intracellular sorting processes.