From Frazier-Jawerth characterizations of Besov spaces to Wavelets and Decomposition spaces

This article describes how the ideas promoted by the fundamental papers published by M. Frazier and B. Jawerth in the eighties have influenced subsequent developments related to the theory of atomic decompositions and Banach frames for function spaces such as the modulation spaces and Besov-Triebel-Lizorkin spaces. Both of these classes of spaces arise as special cases of two different, general constructions of function spaces: coorbit spaces and decomposition spaces. Coorbit spaces are defined by imposing certain decay conditions on the so-called voice transform of the function/distribution under consideration. As a concrete example, one might think of the wavelet transform, leading to the theory of Besov-Triebel-Lizorkin spaces. Decomposition spaces, on the other hand, are defined using certain decompositions in the Fourier domain. For Besov-Triebel-Lizorkin spaces, one uses a dyadic decomposition, while a uniform decomposition yields modulation spaces. Only recently, the second author has established a fruitful connection between modern variants of wavelet theory with respect to general dilation groups (which can be treated in the context of coorbit theory) and a particular family of decomposition spaces. In this way, optimal inclusion results and invariance properties for a variety of smoothness spaces can be established. We will present an outline of these connections and comment on the basic results arising in this context

A new visual trap for Rhagoletis cerasi (L.) (Diptera: Tephritidae).

The European cherry fruit fly, Rhagoletis cerasi (L.) (Diptera: Tephritidae), is the most important pest of sweet cherries in Europe. The aim of our experiments was to develop a new, cost-efficient, lead chromate-free and more eco-friendly trap for monitoring and mass trapping of R. cerasi. Five different-colored yellow panels and three different trap shapes were compared to a standard Rebell® amarillo trap in three experimental orchards in 2012. Trap color F, with a strong increase in reflectance at 500–550 nm and a secondary peak in the UV-region at 300–400 nm, captured significantly more flies than the standard Rebell® amarillo trap. Yellow traps with increased reflectance in the blue region (400–500 nm) were least attractive. Trap shape was of minor importance, as long as the object was three-dimensional and visible from all directions. Based on economic and practical considerations, a cylinder-shaped trap ―UFA-Samen Kirschenfliegenfalle‖ was developed for commercial use and is currently under on-farm evaluation

A Flexible Patch-Based Lattice Boltzmann Parallelization Approach for Heterogeneous GPU-CPU Clusters

Sustaining a large fraction of single GPU performance in parallel computations is considered to be the major problem of GPU-based clusters. In this article, this topic is addressed in the context of a lattice Boltzmann flow solver that is integrated in the WaLBerla software framework. We propose a multi-GPU implementation using a block-structured MPI parallelization, suitable for load balancing and heterogeneous computations on CPUs and GPUs. The overhead required for multi-GPU simulations is discussed in detail and it is demonstrated that the kernel performance can be sustained to a large extent. With our GPU implementation, we achieve nearly perfect weak scalability on InfiniBand clusters. However, in strong scaling scenarios multi-GPUs make less efficient use of the hardware than IBM BG/P and x86 clusters. Hence, a cost analysis must determine the best course of action for a particular simulation task. Additionally, weak scaling results of heterogeneous simulations conducted on CPUs and GPUs simultaneously are presented using clusters equipped with varying node configurations.Comment: 20 pages, 12 figure

A method for optimizing the ambiguity function concentration

International audienceIn the context of signal analysis and transformation in the time-frequency (TF) domain, controlling the shape of a waveform in this domain is an important issue. Depending on the application, a notion of optimal function may be defined through the properties of the ambiguity function. We present an iterative method for providing such optimal functions under a general concentration constraint of the ambiguity function. At each iteration, it follows a variational approach which maximizes the ambiguity localization via a user-defined weight function F . Under certain assumptions on this latter function, it converges to a waveform which is optimal according to the localization criterion defined by F

Periodic and discrete Zak bases

Weyl's displacement operators for position and momentum commute if the product of the elementary displacements equals Planck's constant. Then, their common eigenstates constitute the Zak basis, each state specified by two phase parameters. Upon enforcing a periodic dependence on the phases, one gets a one-to-one mapping of the Hilbert space on the line onto the Hilbert space on the torus. The Fourier coefficients of the periodic Zak bases make up the discrete Zak bases. The two bases are mutually unbiased. We study these bases in detail, including a brief discussion of their relation to Aharonov's modular operators, and mention how they can be used to associate with the single degree of freedom of the line a pair of genuine qubits.Comment: 15 pages, 3 figures; displayed abstract is shortened, see the paper for the complete abstrac

A luciferase-based quick potency assay to predict chondrogenic differentiation.

Chondrogenic differentiation of adipose derived stem cells (ASC) is challenging but highly promising for cartilage repair. Large donor variability of chondrogenic differentiation potential raises the risk for transplantation of cells with reduced efficacy and a low chondrogenic potential. Therefore quick potency assays are required in order to control the potency of the isolated cells before cell transplantation. Current in vitro methods to analyze the differentiation potential are time consuming and thus, a novel enhancer and tissue-specific promoter combination was employed for the detection of chondrogenic differentiation of ASC in a novel quick potency bioassay. Human primary ASC were co-transfected with the Metridia luciferase based collagen type II reporter gene pCMVE_ACDCII-MetLuc together with a Renilla control plasmid and analyzed for their chondrogenic potential. On day 3 after chondrogenic induction, the luciferase activity was induced in all tested donors under three dimensional (3D) culture conditions and in a second approach also under 2D culture conditions. With our newly developed quick potency bioassay we can determine chondrogenic potential already after 3 days of chondrogenic induction and under 2D culture conditions. This will enhance the efficiency of testing cell functionality, which should allow in the future to predict the suitability of cells derived from individual patients for cell therapies, in a very short time and at low costs

Determinants of legacy effects in pine trees - implications from an irrigation-stop experiment

Tree responses to altered water availability range from immediate (e.g. stomatal regulation) to delayed (e.g. crown size adjustment). The interplay of the different response times and processes, and their effects on long-term whole-tree performance, however, is hardly understood. Here we investigated legacy effects on structures and functions of mature Scots pine in a dry inner-Alpine Swiss valley after stopping an 11-yr lasting irrigation treatment. Measured ecophysiological time series were analysed and interpreted with a system-analytic tree model. We found that the irrigation stop led to a cascade of downregulations of physiological and morphological processes with different response times. Biophysical processes responded within days, whereas needle and shoot lengths, crown transparency, and radial stem growth reached control levels after up to 4 yr only. Modelling suggested that organ and carbon reserve turnover rates play a key role for a tree's responsiveness to environmental changes. Needle turnover rate was found to be most important to accurately model stem growth dynamics. We conclude that leaf area and its adjustment time to new conditions is the main determinant for radial stem growth of pine trees as the transpiring area needs to be supported by a proportional amount of sapwood, despite the growth-inhibiting environmental conditions.Peer reviewe

Non-viral transient gene therapy for bone regeneration

Knochendefekte kritischer Größe werden durch massives Trauma oder chirurgische Resektion verursacht und stellen ein signifikantes klinisches Problem dar. Diese Defekte können sich zu Pseudoarthrosen entwickeln und sind weltweit eine Belastung für Patienten und Gesundheitsysteme. Transplantation von autologem Knochen oder Verabreichung von hohen supraphysiologischen Mengen rekombinanter Wachstumsfaktoren sind derzeit die einzigen Behandlungsalternativen mit erheblichen Nebenwirkungen für den Patienten. Aus diesem Grund werden neue, minimal-invasive, kosteneffektive und sichere Behandlungsmethoden erforderlich, welche nicht auf der Verwendung von autologem Gewebe, autologen Stammzellen, Biomaterialien oder rekombinanten Wachstumsfaktoren aufbauen. In dieser Studie wurde nicht-virale transiente somatische Gentherapie, untersucht. die in situ Manipulation von endogenen Zellen zu Überexpression von Wachstumsfaktoren im Defekt ermöglicht. Dies kann zu relativ geringen Kosten und mit potentieller hoher therapeutischer Effizienz erfolgen, da im Defektareal eine kontinuierliche Freisetzung eines endogen produzierten hochaktiven Wachstumsfaktor erreicht wird . Eine hoch-bioaktive Genkombination von bone morphogenetic protein 2 und 7 (BMP2/7) wurde in in vitro Experimenten mit Unterstützung eines neu entwickelten Reportergen Systems identifiziert und anschließend für die Entwicklung von neuen konstitutiven und induzierbaren Co-Expressionsplasmiden eingesetzt. Die Co-Expression von BMP2/7 von diesen konstitutiven und induzierbaren Multi-Kassetten wurde in vitro auf ihr osteogenes Potenzial hin untersucht und mit rekombinanten Wachstumsfaktoren verglichen. Nach erfolgreichen in vitro Experimenten wurden diese Plasmide in ektopen und orthotopen in vivo Modellen mit passivem oder Ultraschall-basiertem Gentransfer (Sonoporation) in Nagetieren getestet. In vitro Experimente zeigten, dass die konstitutiven Multi-Kassetten BMP2/7 Co-Expressionsysteme ein reduziertes osteogenes Potenzial im Vergleich zur Co-Transfektion von BMP2 und BMP7 Plasmiden aufwiesen, welches auf transkriptionale Interferenz zurückgeführt werden kann. Diese transkriptionale Interferenz war von der Orientierung der Expressionskassetten abhängig und trat bei Tandem Orientierung der Expressionskassetten vermehrt auf. Induzierbare Co-Expression von BMP2/7 und osteogene Differenzierung in vitro mittels eines modifizierten TetON-induzierbaren Expressionsplasmides konnte gezielt über einen Induktor (Doxyzyklin) gesteuert werden. In vivo nicht-viraler Gentransfer in ektopen und orthotopen Modellen zeigte, dass Sonoporation die Wahrscheinlichkeit eines erfolgreichen Gentransfers im Vergleich zu passivem Gentransfer bis auf 100% steigern kann. Lokalisierte ektope und orthotope in vivo Genexpression konnte mit Biolumineszenz-Bildgebung und Immunfärbungen nachgewiesen werden. BMP2/7 in vivo Gentransfer mittels konstitutiver oder induzierbarer BMP2/7 Co-Expressionssystemen führte zu potenter Osteoinduktion nach wiederholtem Gentransfer. In vivo Verabreichung des induzierbaren Systems, ermöglichte spezifische Kontrolle der therapeutischen Genexpression über den Induktor Doxyzyklin. Orthotope Evaluierung der BMP2/7 Gentransfer-Strategie deutet auf eine verbesserte Knochenheilung (33% Heilung in der Therapiegruppe) in Femurdefekten kritischer Größe hin. Aus den in vitro und in vivo Ergebnissen schlussfolgernd, wird festgestellt, dass BMP2/7 Co-Expression eine potente osteoinduktive therpeutische Strategie ist, welche über konstitutive oder induzierbare Co-Expressionsplasmide mit passivem oder aktivem Gentransfer verabreicht werden kann. Sonoporation führt zu einer Zunahme der Frequenz erfolgreichen Gentransfers und genaue Kontrolle der Transgen Co-Expression kann durch induzierbare Systeme in vivo gewährleistet werden. Aufrgrund der Ergebnisse kann die Behandlungsstrategie der BMP2/7 in vivo Sonoporation als vielversprechende Alternative zu rekombinanten Wachstumsfaktoren in der Geweberegeneration angesehen werden. Die entwickelte Therapie könnte die Behandlung von Knochendefekten revolutionieren, wenn die Gentransfereffizienz gesteigert und somit die Anzahl repetetiver Behandlungen und DNA Dosis reduziert werden kann.Critical size bone defects, caused by severe tissue trauma or resection surgery represent a challenging clinical problem in trauma surgery/orthopaedics. These defects can lead to non-union fractures, which fail to regenerate and are a substantial burden on patients and health-care systems worldwide. Alternative treatment strategies to conventional fracture management are bone grafting from autologous sources or the application of high doses of recombinant bone morphogenetic protein (BMP)growth factors. While grafting is associated with donor site morbidity, BMPs can lead to adverse effects by supraphysiologic dosing. Therefore, novel treatment modalities are required for the minimally invasive, cost-effective and safe treatment of bone defects, preferably omitting the use of stem cells, biomaterials and recombinant growth factors. Non-viral transient somatic gene therapy offers methods for the in situ manipulation of endogenous cells at the defect site for growth factor expression at relatively low cost and potential high performance, due to endogenous production and release of an active morphogen. It was the aim of this study to design and evaluate a non-viral in vivo gene therapy protocol for osteoinduction. A highly osteoinductive combination of bone morphogenetic protein 2 and 7 therapeutic genes was identified in in vitro experiments, supported by the use of a novel enhanced reporter gene assay for osteogenic differentiation. BMP2/7 was subsequently employed in the design of novel constitutive and inducible therapeutic co-expression plasmids. Multi-cassette based BMP2/7 co-expression from such constitutive or inducible plasmids was characterized and compared to recombinant growth factor induced osteogenic differentiation in vitro. After successful in vitro testing, the novel co-expression plasmids were tested for in vivo osteoinduction using passive gene delivery or active sonoporative gene transfer in ectopic and orthotopic in vivo rodent models. In vitro evaluation of constitutive multi-cassette BMP2/7 co-expression plasmids revealed impaired induction of osteogenic differentiation compared to combined delivery of individual BMP2 and 7 plasmids due to transcriptional interference occurring in the single-plasmid co-expression system. This transcriptional interference related impairment of co-expression associated bioactivity was related to relative transcription cassette orientation, causing stronger interference in tandem expression cassette orientation. Inducible co-expression of BMP2/7 from a single-vector TetON inducible expression plasmid, showed potent osteoinduction and tight control over transgene expression in vitro. In vivo gene delivery studies in ectopic and orthotopic models showed that sonoporation could enhance non-viral gene delivery compared to passive gene transfer, increasing the overall rate of successful gene delivery and osteoinduction up to 100%. Localized ectopic and orthotopic gene expression was confirmed by bioluminescence imaging and immunohistochemistry. BMP2/7 in vivo gene delivery by constitutive or inducible BMP2/7 co-expression systems demonstrated potent osteoinduction in vivo after repeated delivery with either passive or sonoporative gene transfer. In vivo gene delivery using the inducible system again demonstrated tight regulation of osteogenesis via the inductor doxycycline. Orthotopic testing (0% union rate) indicated an enhancing effect of non-viral BMP2/7 gene co-delivery in critical sized femur fracture models, leading to a union rate of 33% in the treatment group. We conclude from our in vitro and in vivo findings that BMP2/7 is a potent osteoinductive therapeutic gene combination, which can be delivered in constitutive or inducible multi-cassette co-expression plasmids for osteoinduction using passive or sonoporative gene transfer in vivo. Sonoporation has been shown to enhance overall gene transfer probability. Tight control of in vivo transgene expression has been demonstrated using inducible systems. Therefore, the novel treatment approach of sonoporative BMP2/7 co-expression in vivo can be considered a promising alternative to recombinant growth factor application in tissue regeneration and could provide a potential novel therapy for clinical translation after further improvement. This includes establishing higher gene transfer efficacy & reducing the number of repetitive treatments and a reduction of DNA dosing