Fast patterning of poly(methyl methacrylate) by a novel soft molding approach and its application to the fabrication of silver structures

A novel single-step approach for the fabrication of poly(methyl methacrylate) structures by soft molding of a 5 wt% solution in acetone is reported. The use of a low weight solution and of a solvent with high volatility ensures a very fast patterning, down to 10 s. In addition, the process is extremely simple and cost-effective, since just one elastomeric mold is needed, and areas as large as 1 cm² were patterned uniformly and defect-free. The process was applied to the fabrication of silver structures by silver deposition via electroless plating or evaporation followed by poly(methyl methacrylate) removal. Structures of various shapes and sizes, with dimensions in the micrometer and submicrometer range were successfully fabricated, showing the versatility of the process. This silver patterning process is particularly well suited for applications in microelectronics and optoelectronics, such as the fabrication of transparent electrodes for solar cells and displays, manufacturing of metal etching masks and wiring of printed circuits.     

Micro-computed tomography for the investigation of stationary liquid–liquid and liquid–gas interfaces in capillaries

For better understanding and optimization of multiphase flow in miniaturized devices, micro-computed tomography (μCT) is a promising visualization tool, as it is nondestructive, three-dimensional, and offers a high spatial resolution. Today, computed tomography (CT) is a standard imaging technique. However, using CT in microfluidics is still challenging, since X-ray related artifacts, low phase contrast, and limited spatial resolution complicate the exact localization of interfaces. We apply μCT for the characterization of stationary interfaces in thin capillaries. The entire workflow for imaging stationary interfaces in capillaries, from image acquisition to the analysis of interfaces, is presented. Special emphasis is given to an in-house developed segmentation routine. For demonstration purposes, contact angles of water, liquid polydimethylsiloxane, and air in FEP, glass, and PMMA are determined and the influence of gravity on interface formation is discussed. This work comprises the first steps for a systematic 3D investigation of multiphase flows in capillaries using μCT.     

Real-Time BODIPY-Binding Assay To Screen Inhibitors of the Early Oligomerization Process of Aβ1–42 Peptide

Misfolding and aggregation of amyloid β1–42 peptide (Aβ1–42) play a central role in the pathogenesis of Alzheimer's disease (AD). Targeting the highly cytotoxic oligomeric species formed during the early stages of the aggregation process represents a promising therapeutic strategy to reduce the toxicity associated with Aβ1–42. Currently, the thioflavin T (ThT) assay is the only established spectrofluorometric method to screen aggregation inhibitors. The success of the ThT assay is that it can detect Aβ1–42 aggregates with high β-sheet content, such as protofibrils or fibrils, which appear in the late aggregation steps. Unfortunately, by using the ThT assay, the detection of inhibitors of early soluble oligomers that present a low β-sheet character is challenging. Herein, a new, facile, and robust boron-dipyrromethene (BODIPY) real-time assay suitable for 96-well plate format, which allows screening of compounds as selective inhibitors of the formation of Aβ1–42 oligomers, is reported. These inhibitors decrease the cellular toxicity of Aβ1–42, although they fail in the ThT assay. The findings have been confirmed and validated by structural analysis and cell viability assays under comparable experimental conditions. It is demonstrated that the BODIPY assay is a convenient method to screen and discover new candidate compounds that slow down or stop the pathological early oligomerization process and are active in the cellular assay. Therefore, it is a suitable complementary screening method of the current ThT assay.     

Biomass retention following whole-tree, energy wood harvests in central Maine: Adherence to five state guidelines

The expansion of the bioenergy industry in Maine has led to an increase in integrated roundwood and energy wood whole-tree harvesting. A better understanding of the amounts of logging residue left unrecovered on whole-tree harvested sites will enable the refinement of available forest residue estimates for Maine and the assessment of the potential effect of such harvesting on forest health. Several states have developed biomass harvesting guidelines in response to concerns generated from an expanding bioenergy industry. In this study downed wood and snags were inventoried on twelve sites in central Maine that had recently been whole-tree harvested for roundwood and energy wood. The percentage of harvested material retained as residue on the study sites was determined. On average, 45% of the energy wood generated during the harvest was left on site. This removal efficiency must be considered when developing forest residue availability estimates. Additionally, the volumes of logging residue were compared to measurable criteria from biomass and biodiversity guidelines of several states. We found that enough fine woody material (<15 cm diameter) remained on the harvest sites to meet the guideline criteria; however, the quantities of coarse woody material (≥15 cm diameter), large logs (≥38 cm dbh), and snags (≥25 cm dbh) were insufficient to meet the guideline criteria. These deficiencies likely resulted from prior forest practices rather than from the current energy wood removal. Retaining more trees of larger sizes in the future can address this concern.     

Cultural dimensions of intersubjectivity: Negotiating “sameness” and “otherness” in the analytic relationship.

The cultural diversity of Western society has created an increasingly complex psychoanalytic intersubjective field. Cultural, class, racial, and familial dimensions of experience can never be separated in the psyche of the patient or analyst or in the analytic relationship. But the melding of these influences results in particular meanings for each patient, analyst, and analytic couple, and may be crucial to address for authentic connection and change to occur. A clinical case is presented in which uniquely melded cultural, class, and psychological meanings became enacted between patient and analyst, stimulating unexpected feelings in both, which enabled the emergence of a bridge across an apparent gulf of “otherness.” (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Implicit influence of affective postures on the perception of others: You can't show me how I feel.

This study examined how one's own posture influences the perception of another's posture in a task with implicit affective information. In 2 experiments, participants assumed or viewed a body posture and then compared that posture with a viewed posture. They were not told that postures varied in affective valence: positive, negative, neutral-abstract, or neutral-meaningful. Posture affect influenced both accuracy and response time measures of posture discrimination. Participants were slower and less accurate for targets that matched an assumed posture, but only for affective postures. This pattern did not hold for matching affectively neutral postures (meaningful or not), nonmatching postures, or for purely visual comparisons. These results are consistent with both cognitive embodiment theories postulating that personal body posture influences the perception of other's postures and emotional embodiment theories postulating sensorimotor and emotional simulation processes that create correspondences between one's own and another's emotional postures. Nonetheless, these findings differ from studies finding facilitation for explicit emotional judgments of affective congruence. People use different information depending on task requirements. The assumption of an affective posture may activate simulations of personal emotional experiences that may, in turn, serve to differentiate personal posture perception from ostensibly the same posture in another person. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Biochemistry of Citric Acid Production from Rapeseed Oil by <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> Yeast

The growth of wild type strain Yarrowia lipolytica VKM Y-2373 and its mutant Y. lipolytica NG40/UV7 as well as the biosynthesis of citric and isocitric acid on rapeseed oil were studied. It was indicated that the initial step of assimilation of rapeseed oil in the yeast Y. lipolytica is its hydrolysis by extracellular lipases with the formation of glycerol and fatty acids, which appear in the medium in the phase of active growth. The concentrations of these metabolites were changed insignificantly upon further cultivation. Lipase and the key enzymes of glycerol metabolism (glycerol kinase) and the glyoxylate cycle responsible for the metabolism of fatty acids (isocitrate lyase and malate synthase) are induced just at the beginning of the growth phase and remain active in the course of further cultivation. These results, taken together, suggest that glycerol and fatty acids available in the medium do not suppress the metabolism of each other. Citric acid production and a ratio between citric and isocitric acids depended on the strain used. It was revealed that the wild strain produced almost equal amounts of citric and isocitric acids while the mutant produced only citric acid (175 g/L) with a yield of 1.5 g of CA per g of oil.     

New Bitopic Ligands for the Group Actinide Separation by Solvent Extraction

Abstract

The synthesis and evaluation of solvent extraction performance of N,N,N′,N′-tetraalkyl-6,6″-(2,2′:6′,2″-terpyridine)diamides and N,N′-diethyl-N,N′-diphenyl-6,6″-(2,2′:6′,2″-terpyridine)diamide are reported here. These new bitopic ligands were found to extract actinides in different oxidation states (U(VI), Np(V and VI), Pu(IV), Am(III), and Cm(III)) from 3 M nitric acid. The presence of three soft nitrogen donors led to the selective extraction of actinides(III) over lanthanides(III) (Ce, Eu) and the presence of two amide functional groups grafted to the terpyridine unit allowed the extraction to occur from a highly acidic medium by minimizing the basicity of the ligand. Ligands bearing long alkyl chains (C4 and C8) or phenyl groups showed increased performances in a polar diluent like nitrobenzene.