Plasmon‐Enhanced Photocurrent of Photosynthetic Pigment Proteins on Nanoporous Silver

In a quest to fabricate novel solar energy materials, the high quantum efficiency and long charge separated states of photosynthetic pigment‐proteins are being exploited through their direct incorporation in bioelectronic devices. In this work, a biohybrid photocathode comprised of bacterial reaction center‐light harvesting 1 (RC‐LH1) complexes self‐assembled on a nanostructured silver substrate yields a peak photocurrent of 166 μA cm^?2 under 1 sun illumination, and a maximum of 416 μA cm^?2 under 4 suns, the highest reported to date on a bare metal electrode. A 2.5‐fold plasmonic enhancement of light absorption per RC‐LH1 complex is observed on the rough silver substrate. This plasmonic interaction is assessed using confocal fluorescence microscopy, revealing an increase of fluorescence yield, and radiative rate of the RC‐LH1 complexes, signatures of plasmon‐enhanced fluorescence. Nanostructuring of the silver substrate also enhanced the stability of the protein under continuous illumination by almost an order of magnitude relative to a nonstructured bulk silver control. Due to its ease of construction, increased protein loading capacity, stability, and more efficient use of light, this hybrid material is an excellent candidate for further development of plasmon‐enhanced biosensors and biophotovoltaic devices.     

Remaining time and opportunities at work: Relationships between age, work characteristics, and occupational future time perspective.

The authors adapted the concept of future time perspective (FTP) to the work context and examined its relationships with age and work characteristics (job complexity and control). Structural equation modeling of data from 176 employees of various occupations showed that age is negatively related to 2 distinct dimensions of occupational FTP: remaining time and remaining opportunities. Work characteristics (job complexity and control) were positively related to remaining opportunities and moderated the relationship between age and remaining opportunities, such that the relationship became weaker with increasing levels of job complexity and control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Discussion of Simultaneous Localization and Mapping

This paper aims at a discussion of the structure of the SLAM problem. The analysis is not strictly formal but based both on informal studies and mathematical derivation. The first part highlights the structure of uncertainty of an estimated map with the key result being “Certainty of Relations despite Uncertainty of Positions”. A formal proof for approximate sparsity of so-called information matrices occurring in SLAM is sketched. It supports the above mentioned characterization and provides a foundation for algorithms based on sparse information matrices. Further, issues of nonlinearity and the duality between information and covariance matrices are discussed and related to common methods for solving SLAM. Finally, three requirements concerning map quality, storage space and computation time an ideal SLAM solution should have are proposed. The current state of the art is discussed with respect to these requirements including a formal specification of the term “map quality”. This article is based on research conducted during the author's Ph.D. studies at the German Aerospace Center (DLR) in Oberpfaffenhofen. Udo Frese was born in Minden, Germany in 1972. He received the Diploma degree in computer science from the University of Paderborn in 1997. From 1998 to 2003 he was a Ph.D. student at the German Aerospace Center in Oberpfaffenhofen. In 2004 he joined University of Bremen. His research interests are mobile robotic, simultaneous localization and mapping and computer vision.     

Graphical interactive generation of gravity and magnetic fields

This paper presents a MATLAB^®- based geopotential field generator called GamField that constructs and visualizes subsurface sources in 3-D space and computes their gravity and magnetic effects. GamField also computes anomaly gradients and remanent magnetization effects. The user inputs Cartesian prisms along with their physical properties to fabricate subsurface sources. Examples illustrating the utility of GamField for synthetic anomaly generation of gravity and magnetic fields are shown. ftp://ftp.ingv.it/pub/alessandro.pignatelli/Pignatelli     

Social support as a moderator of the relationship between work stressors and psychological dysfunctioning: A longitudinal study with objective measures.

The match hypothesis proposed by S. Cohen and T. A. Wills (1985) is extended, and the buffer effect of social support is tested within a longitudinal study with objective measures (N?=?90 male blue-collar workers in the German metal industry). Stressors at work were ascertained by observers and a variant of a peer rating. Psychological, physical, and social stressors at work and leisure time stressors were ascertained. The dependent variables of dysfunctioning were psychosomatic complaints, depression, irritation/strain, and (social) anxiety. There were moderator effects of social support on the relationship between stressors and psychological dysfunctioning. Results are in line with the match hypothesis as social stressors and socially oriented aspects of psychological dysfunctioning were affected most strongly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sortierverfahren für die kombinierte maschinelle und visuelle Festigkeitssortierung

The aim of this study was to show the possibility of the classification of structural timber into strength class C35 according to EN 338 by using combined visual and machine strength grading techniques. Three different visual-machine strength grading combinations are devised for allocating sawn timber into strength class C35. They are composed on the one hand of the visual grading according to DIN 4074-1 and on the other hand of machine strength grading of green or dry sawn timber by measuring the dynamic MOE or the apparent density of sawn timber. In order to allocate sawn timber into strength class C35 the machine settings for these combinations were estimated. The grading results show that combinations based on the dynamic MOE are suitable for strength grading of lamellae for glued laminated timber and joists. Combinations based on apparent density are also suitable for strength grading lamellae for glued laminated timber.     

Adaptive wavelet graph model for Bayesian tomographic reconstruction

We introduce an adaptive wavelet graph image model applicable to Bayesian tomographic reconstruction and other problems with nonlocal observations. The proposed model captures coarse-to-fine scale dependencies in the wavelet tree by modeling the conditional distribution of wavelet coefficients given overlapping windows of scaling coefficients containing coarse scale information. This results in a graph dependency structure which is more general than a quadtree, enabling the model to produce smooth estimates even for simple wavelet bases such as the Haar basis. The inter-scale dependencies of the wavelet graph model are specified using a spatially nonhomogeneous Gaussian distribution with parameters at each scale and location. The parameters of this distribution are selected adaptively using nonlinear classification of coarse scale data. The nonlinear adaptation mechanism is based on a set of training images. In conjunction with the wavelet graph model, we present a computationally efficient multiresolution image reconstruction algorithm. This algorithm is based on iterative Bayesian space domain optimization using scale recursive updates of the wavelet graph prior model. In contrast to performing the optimization over the wavelet coefficients, the space domain formulation facilitates enforcement of pixel positivity constraints. Results indicate that the proposed framework can improve reconstruction quality over fixed resolution Bayesian methods.     

Bending strength of spruce glulam

A glulam strength model where the bending strength depends both on the board tensile strength and the finger joint tensile strength is a completely transparent model being particularly suitable to determine requirements for the board and for the finger joint tensile strength of glulam made of both visually or mechanically strength graded boards. This article describes the application of these principles to an alternative and new strength model for spruce glulam. In order to determine the influence of the board and finger joint strength on glulam bending strength a numerical study was performed by means of simulated glulam beams. According to the findings current requirements for boards and finger joints are insufficient to ensure the nominal strength values of glulam strength classes established in EN 1194.     

The Role of Mitochondrial Function in Peripheral Arterial Disease: Insights from Translational Studies

Recent evidence demonstrates an involvement of impaired mitochondrial function in peripheral arterial disease (PAD) development. Specific impairments have been assessed by different methodological in-vivo (near-infrared spectroscopy, ³¹P magnetic resonance spectroscopy), as well as in-vitro approaches (Western blotting of mitochondrial proteins and enzymes, assays of mitochondrial function and content). While effects differ with regard to disease severity, chronic malperfusion impacts subcellular energy homeostasis, and repeating cycles of ischemia and reperfusion contribute to PAD disease progression by increasing mitochondrial reactive oxygen species production and impairing mitochondrial function. With the leading clinical symptom of decreased walking capacity due to intermittent claudication, PAD patients suffer from a subsequent reduction of quality of life. Different treatment modalities, such as physical activity and revascularization procedures, can aid mitochondrial recovery. While the relevance of these modalities for mitochondrial functional recovery is still a matter of debate, recent research indicates the importance of revascularization procedures, with increased physical activity levels being a subordinate contributor, at least during mild stages of PAD. With an additional focus on the role of revascularization procedures on mitochondria and the identification of suitable mitochondrial markers in PAD, this review aims to critically evaluate the relevance of mitochondrial function in PAD development and progression.