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Zusammenfassung Fragestellung Ziel dieser Studie war es, den Unterschied im Behandlungserfolg nach phototherapeutischer Keratektomie (PTK) bei Salzmannʼscher nodulärer Degeneration (SND) mittels zweier Excimerlaser mit unterschiedlichen Spezifikationen zu untersuchen. Patienten und Methoden Im Zeitraum von 2007 bis 2017 wurden 272 PTKs, die an 246 Augen mit SND von 181 Patienten durchgeführt wurden, retrospektiv untersucht. Bis 2014 wurde für die PTK nach manueller Pannektomie der Excimerlaser MEL70 (Carl Zeiss Meditec Vertriebsgesellschaft mbH, Oberkochen, Deutschland) verwendet, danach der Amaris 750S (Schwind eye-tech-solutions GmbH, Kleinostheim, Deutschland). Der Therapieerfolg wurde anhand folgender Parameter beurteilt: Visus, Refraktion und Astigmatismus sowie die Pachymetrie und die Endothelzellmessung zu den Zeitpunkten T1 = präoperativ, T2 = 6-Wochen-Kontrolle, T3 = 6-Monats-Kontrolle. Zum Vergleich der Daten wurden der Wilcoxon-Mann-Whitney-U-Test und der Chi-Quadrat-Test mit einem Signifikanzniveau von 5% genutzt. Ergebnisse Nach 6 Monaten stieg der Visus nur in der Schwind-Gruppe signifikant um 0,17 ± 0,33 (logMAR p Schlussfolgerung In beiden Studiengruppen profitierten die Patienten von einer PTK bei SND. Für die Schwind-Gruppe konnte jedoch eine signifikant größere Verbesserung von Visus und Refraktion festgestellt werden als für die Zeiss-Gruppe. Im Gegensatz zum üblichen hyperopisierenden Effekt der PTK bei anderen Diagnosen zeigte sich bei SND ein sog. „myopic shift“, der sich aus den oft mittelperipher liegenden SND-Knoten und dem damit verbundenen asymmetrischen Tränenfilmpooling präoperativ erklären lässt.

Scaling laws are used to scale-up calculation or measurement results from a prototype structure to those of an original structure or vice versa. The scaling laws of mechanical structures are usually obtained from their equations of motion or from a dimensional analysis. This paper proposes scaling laws that are represented by a power law. The power law is directly deduced from the Π -theorem of similitude theory and the coefficients of the power law are obtained from first order sensitivities (sensitivity-based scaling laws). Among existing similitude analysis methods such as dimensional analysis the sensitivity-based scaling laws can be directly obtained from a model without a priori knowledge of its scaling behavior, e.g., from a finite element (FE) model. The applicability of the sensitivity-based scaling laws is demonstrated in three case studies. A simply supported rectangular plate subject to mechanical vibrations is modeled by an analytical approach based on the Kirchhoff plate theory and by an FE model based on the Mindlin-Reissner theory. The plate’s dimensions are considered as design parameters for the sensitivity-based scaling laws. It is found in the first case study that the sensitivity-based scaling laws exactly predict the natural frequencies and the mean squared transfer admittances of scaled models from those of the original plate. This is in agreement with current literature and, thus, the method proposed in this paper can be considered verified. In the second case study the sensitivity-based scaling laws are directly obtained from the FE model. A good accuracy of the predicted vibration responses of the scaled models is found since (1) the scaled model and the original one are in similitude, i.e., the mode shape order and the damping are kept, and (2) the scaled plate can still be considered thin. The latter is assessed by the length (or width) to thickness ratios of the investigated plates and a lower bound is proposed. The third case study comprises a simplified car undercarriage to demonstrate the applicability of the method in practical design engineering. Besides the geometry parameters the material properties are incorporated in the sensitivity-based scaling laws as well. It is found that the natural frequencies as well as the vibration velocities at an arbitrarily chosen receiver point of the scaled models can be accurately predicted from those of the original one for complete similitude conditions.

In structures, high vibration levels can destroy components; therefore, the reduction of the vibration levels represents a fundamental target in the industrial field. The structural intensity (STI) field provides information about the energy flow that propagates within a structure. It shows the position of dampers in structures, thus, it can be used for solving structure-borne noise problems. The analysis of the energy distribution on a structure allows to understand where to implement locally concentrated modifications introducing damping patches in order to reduce structure-borne noise. The aim of this paper is to investigate the structural intensity in composite structures and to evaluate the influence of some modeling parameters, such as mesh density, structural damping, etc., on the accuracy of the results. In this paper, numerical investigations on the STI in a fiber composite plate are carried out. Two different numerical models are considered: the first one with solid elements, the second one with shell elements. The two-dimensional model does not allow to analyze and study the composite plate on micro level. The first law of thermodynamics allows to define the accuracy of the STI evaluations. The investigation on two-dimensional and three-dimensional composite structure modeling presents the limits and the advantages of the two different types of approach. The different characteristics of the STI fields provided by these models are analyzed in order to understand the difference between local and global approach.

Follicle-stimulating hormone (FSH) is essential for primate reproduction and acts via the FSH-receptor (FSHR). Although the FSHR expression is highly cell-specific, knowledge of the FSHR promoter and its transcriptional regulation is very limited. We applied a comparative genomic approach of important primate lineages to characterize the FSHR core promoter region. The core promoter sequences of the human and different primate species display significant variations in species-specific promoter activities shown by relative luciferase activity (RLA), ranging from 0.7-fold in the bonobo up to 3.5-fold in the chimpanzee compared to human. Comparison of the core promoter sequences revealed only very few interspecies nucleotide mismatches. Sequence homology ranged between 88% in the marmoset to 98% in chimpanzee compared to human FSHR. Mutagenesis of a single nucleotide next to a putative E-twenty-six (ETS) binding site caused a significant increase for human and a decrease for chimpanzee in RLA. An accompanying change in the pattern of protein binding to mutated human and chimpanzee ETS binding sites was demonstrated by EMSA, confirming a hitherto unknown role for this ETS binding site in FSHR promoter activity. Although the FSHR promoter displays a great sequence homology among primates, single nucleotide changes have significant impact on FSHR promoter activity. Thus promoter studies of closely related species could yield important insights into different regulatory promoter elements caused by nucleotide substitutions.

The Genuine Progress Indicator (GPI), a version of the Index of Sustainable Economic Welfare (ISEW), is a significantly more comprehensive approach to assessing economic progress than conventional measures like gross domestic product (GDP). GPI adjusts for income distribution effects, the value of household and volunteer work, costs of mobility and pollution, and the depletion of social and natural capital. ISEW or GPI have been estimated for several countries around the world and a few Canadian provinces, but we report here on the first multi-scale application at the city, county and state levels in Vermont, USA. We show that it is feasible to apply the GPI approach at these smaller scales and to compare across scales and with the national average. Data limitations and problems still exist, but potential solutions to these problems also exist. All three Vermont scales had significantly higher GPI per capita since 1980 than the national average, indicating the major differences that can exist within countries. The GPI per capita for all Vermont scales was similar to the national average in the 1950–1980 period, but more than twice the national average by 2000. The main factors explaining this difference had to do with Vermont’s much better environmental performance than the national average in the post-1980 period. D 2004 Elsevier B.V. All rights reserved.

The New World monkey (NWM),Callithrix jacchus, a preferred model in medical research, displays an interesting endocrine regulation of reproduction: LH, the heterodimeric glycoprotein hormone, is functionally replaced by the chorionic gonadotropin (CG), a hormone indispensable for establishment of pregnancy in humans and normally expressed in the placenta. In the marmoset pituitary, the expression of the β-subunit (CGB) gene is regulated similar to human LH β-subunit, but its placental regulation is unknown. This study intended to decipher the underlying mechanism of tissue-specific expression ofCGBin the marmoset placenta. We identified a new placental transcriptional start site, described a new, previously undiscovered exon, and define a novel placental core promoter in the marmosetCGBgene. This promoter contains a TATA box and binding sites for activating protein 2 and selective promoter factor 1, the latter acting synergistically by forming a regulation cassette. Differential first exon usage directed the tissue-specific expression. Methylation analyses revealed a tissue-specific pattern in the placental promoter indicating additional epigenetic regulation of gene expression. Our findings point toward a hitherto unknown evolutionary plasticity in the LH/CG hormonal system in NWM, which could be used as a model to study human CGB regulation in clinical pathologies.