Sensing of Alkylating Agents Using Organic Field‐Effect Transistors

Alkylating agents are simple and reactive molecules that are commonly used in many and diverse fields, such as organic synthesis, medicine, and agriculture. Some highly reactive alkylating species are also being used as blister chemical warfare agents. The detection and identification of alkylating agent is not a trivial issue because of their high reactivity and simple structure. Here, a novel polythiophene derivative that is capable of reacting with alkylating agents is reported, along with its application in direct electrical sensing of alkylators using an organic field‐effect transistor, OFET, device. Upon reacting with alkylators, the OFET containing the new polythiophene analogue as its channel becomes conductive, and the gate effect is lost; this is in marked contrast to the response of the OFET to “innocent” vapors, such as alcohols and acetone. By following the drain–source current under gate bias, one can easily follow the processes of absorption of the analyte to the polythiophene channel and their subsequent reaction.     

Increased mass transport at lithographically defined 3-D porous carbon electrodes

Increased mass transport due to hemispherical diffusion is observed to occur in 3D porous carbon electrodes defined by interferometric lithography. Enhanced catalytic methanol oxidation, after modifying the porous carbon with palladium nanoparticles, and uncharacteristically uniform conducting polymer deposition into the structures are demonstrated. Both examples result in two regions of hierarchical porosity that can be created to maximize surface area, via nanostructuring, within the extended porous network, while taking advantage of hemispherical diffusion through the open pores.     

Accelerated Wound Border Closure Using a Microemulsion Containing Non-Inhibitory Recombinant α1-Antitrypsin

Wound healing requires a non-compromising combination of inflammatory and anti-inflammatory processes. Human α1-antitrypsin (hAAT), a circulating glycoprotein that rises during acute-phase responses and during healthy pregnancies, is tissue-protective and tolerance-inducing; although anti-inflammatory, hAAT enhances revascularization. hAAT blocks tissue-degrading enzymes, including neutrophil elastase; it is, therefore, unclear how wound healing might improve under hAAT-rich conditions. Here, wound healing was examined in the presence of recombinant hAAT (hAAT^WT) and protease-inhibition-lacking hAAT (hAAT^CP). The impact of both hAAT forms was determined by an epithelial cell gap closure assay, and by excisional skin injuries via a microemulsion optimized for open wounds. Neutrophilic infiltration was examined after 8 h. According to results, both hAAT forms accelerated epithelial gap closure and excisional wound closure, particularly at early time points. Unlike dexamethasone-treated wounds, both resulted in closed borders at the 8-h time point. In untreated and hAAT^CP-treated wounds, leukocytic infiltrates were widespread, in hAAT^WT-treated wounds compartmentalized and in dexamethasone-treated wounds, scarce. Both hAAT forms decreased interleukin-1β and increased VEGF gene expression. In conclusion hAAT improves epithelial cell migration and outcomes of in vivo wounds irrespective of protease inhibition. While both forms of hAAT allow neutrophils to infiltrate, only native hAAT created discrete neutrophilic tissue clusters.     

Clinical supervision from the standpoint of cognitive-behavior therapy.

This article presents an approach to supervising cognitive-behavior therapists that is closely related to the process and content of cognitive-behavior therapy (CBT). The goal of CBT is to help therapists adopt the philosophy of CBT as the basic approach for changing clients' cognitions, emotions, and behaviors. A secondary goal is to teach therapists specific techniques. The seven major features of CBT and their implications for supervision are described: therapy as a meaning-making process; systematic and goal directed therapy; practicing and experiencing; therapy as a collaborative effort; person-focused therapy; the therapists as a facilitator of change and development; and empowerment of the client with self-change skills. Some of the major dilemmas and constraints in CBT supervision that are derived from adapting the principles of therapy to supervision are discussed as well as the need for supervision outcome research and recommendations for its implementation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Image segmentation by probabilistic bottom-up aggregation and cue integration

We present a bottom-up aggregation approach to image segmentation. Beginning with an image, we execute a sequence of steps in which pixels are gradually merged to produce larger and larger regions. In each step, we consider pairs of adjacent regions and provide a probability measure to assess whether or not they should be included in the same segment. Our probabilistic formulation takes into account intensity and texture distributions in a local area around each region. It further incorporates priors based on the geometry of the regions. Finally, posteriors based on intensity and texture cues are combined using “a mixture of experts” formulation. This probabilistic approach is integrated into a graph coarsening scheme, providing a complete hierarchical segmentation of the image. The algorithm complexity is linear in the number of the image pixels and it requires almost no user-tuned parameters. In addition, we provide a novel evaluation scheme for image segmentation algorithms, attempting to avoid human semantic considerations that are out of scope for segmentation algorithms. Using this novel evaluation scheme, we test our method and provide a comparison to several existing segmentation algorithms.     

3D face reconstruction from a single image using a single reference face shape

Human faces are remarkably similar in global properties, including size, aspect ratio, and location of main features, but can vary considerably in details across individuals, gender, race, or due to facial expression. We propose a novel method for 3D shape recovery of faces that exploits the similarity of faces. Our method obtains as input a single image and uses a mere single 3D reference model of a different person's face. Classical reconstruction methods from single images, i.e., shape-from-shading, require knowledge of the reflectance properties and lighting as well as depth values for boundary conditions. Recent methods circumvent these requirements by representing input faces as combinations (of hundreds) of stored 3D models. We propose instead to use the input image as a guide to "mold" a single reference model to reach a reconstruction of the sought 3D shape. Our method assumes Lambertian reflectance and uses harmonic representations of lighting. It has been tested on images taken under controlled viewing conditions as well as on uncontrolled images downloaded from the Internet, demonstrating its accuracy and robustness under a variety of imaging conditions and overcoming significant differences in shape between the input and reference individuals including differences in facial expressions, gender, and race.     

A novel method for on-orbit measurement of space materials degradation

The low Earth orbit (LEO) environment is considered hazardous to spacecraft, resulting in materials degradation. Currently, in order to evaluate the degradation of materials in LEO, a retrieval of space exposed samples is required. In this study, a novel approach is proposed to evaluate degradation of materials in LEO without the need of retrieval. The method is utilizing photovoltaic cells (PVCs), an existing component onboard of any satellite. The PVCs are coated by various materials which are sensitive to different LEO constituents, such as atomic oxygen (AO) or ultra-violet (UV) radiation. The method's acronym is ORMADD (on-ORbit MAterials Degradation Detector). The ORMADD's principle of operation is based on measuring the PVC output power which depends on the cell coating material's optical transmission. Erosion of the coating by AO or coloring due to UV radiation affects its optical transmission and, accordingly, the PVC output. The ORMADD performance was tested using different coatings, such as polyimide and amorphous carbon (sensitive to AO), and siloxane based coating which is sensitive to UV radiation. The proposed ORMADD reveals sensitivity to different LEO components and can be used either as material degradation detector or as an AO monitor.     

Observations on Vertical Variability in Groundwater Quality: Implications for Aquifer Management

This work demonstrates significant vertical variability in the chemical composition of groundwater (Cl⁻ from 150 to 550 mg/L, NO₃^-{\rm{NO}}_{3}^{-} from 3 to 70 mg/L, trichloroethene from 350 to 55,000 μg/L and Cr_Total from 3 to 2,900 μg/L) along a 130 m thick vertical section passing through two subaquifers of the Costal Plain aquifer of Israel. Water samples were obtained by multilevel sampler under natural gradient flow conditions from a monitoring well which penetrates the entire aquifer. The vertical chemical variability detected at a single point in time in this well was found to be similar to the range of concentrations detected for Cl⁻ in pumping wells located over an area of about 1,000 km² in the same aquifer. Similarly, vertical variations in NO₃^-{\rm{NO}}_{3}^{-} concentration in the single monitoring well represent more than 50% of the total variation in nitrate levels in pumping wells sampled across the entire aquifer. These results graphically illustrate that data from pumping wells, which extract unknown mixtures of groundwater from different depths, cannot provide adequate information about groundwater quality for management purposes.