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Air-blast loading is a serious threat to military and civil vehicles, buildings, containers, and cargo. Applications of sandwich-structured composites have attracted increasing interest in modern lightweight design and in the construction of dynamic loading regimes due to their high resistance against blast and ballistic impacts. The functional properties of such composites are determined by the interplay of their face sheet material and the employed core topology. The core topology is the most important parameter affecting the structural behavior of sandwich composites. Therefore, this contribution presents a thorough numerical investigation of different core topologies in sandwich-structured composites subjected to blast loading. Special emphasis is put on prismatic and lattice core topologies displaying auxetic and classical non-auxetic deformation characteristics in order to illustrate the beneficial properties of auxetic core topologies. Their dynamic responses, elastic and plastic deformations, failure mechanisms, and energy absorption capabilities are numerically analyzed and compared. The numerical studies are performed by means of the commercial finite element code ABAQUS/Explicit, including a model for structural failure.

The aim of this biomechanical in vitro study was to answer the question whether the meniscus acts as a shock absorber in the knee joint or not. The soft tissue of fourteen porcine knee joints was removed, leaving the capsuloligamentous structures intact. The joints were mounted in 45° neutral knee flexion in a previously validated droptower setup. Six joints were exposed to an impact load of 3.54 J, and the resultant loss factor (η) was calculated. Then, the setup was modified to allow sinusoidal loading under dynamic mechanical analysis (DMA) conditions. The remaining eight knee joints were exposed to 10 frequencies ranging from 0.1 to 5 Hz at a static load of 1210 N and a superimposed sinusoidal load of 910 N (2.12 times body weight). Forces (F) and deformation (l) were continuously recorded, and the loss factor (tan δ) was calculated. For both experiments, four meniscus states (intact, medial posterior root avulsion, medial meniscectomy, and total lateral and medial meniscectomy) were investigated. During the droptower experiments, the intact state indicated a loss factor of η = 0.1. Except for the root avulsion state (−15%, p = 0.12), the loss factor decreased (p < 0.046) up to 68% for the total meniscectomy state (p = 0.028) when compared to the intact state. Sinusoidal DMA testing revealed that knees with an intact meniscus had the highest loss factors, ranging from 0.10 to 0.15. Any surgical manipulation lowered the damping ability: Medial meniscectomy resulted in a reduction of 24%, while the resection of both menisci lowered tan δ by 18% compared to the intact state. This biomechanical in vitro study indicates that the shock-absorbing ability of a knee joint is lower when meniscal tissue is resected. In other words, the meniscus contributes to the shock absorption of the knee joint not only during impact loads, but also during sinusoidal loads. The findings may have an impact on the rehabilitation of young, meniscectomized patients who want to return to sports. Consequently, such patients are exposed to critical loads on the articular cartilage, especially when performing sports with recurring impact loads transmitted through the knee joint surfaces.

Kendi kendini iyileştiren yapılarda meydana gelen mikro ve makro hasarlar iyileştirici sistemler ile onarılabilmektedir. Böylelikle, malzemelerin yapısal bütünlükleri korunabilme ve tekrarlı kullanım olanakları sağlanabilmektedir. Bu çalışmada yapısal hasarların onarılmasını sağlayan makro kapsüller geliştirilmiştir. Yaklaşık 3 mm çapındaki makro kapsüllerin içerisi 3 farklı iyileşme yeteneğine sahip ajanlar ile doldurulmuştur. İlk olarak epoksi reçine ve kürleştirici ajanlar ile doldurularak hasar sonrası kusurlu bölgelerde iyileşme sağlanmıştır. Sonrasında hasarın geometrik olarak iyileşmesi amacıyla hacimce 17 kat köpürme yeteneğine sahip poliüretan ajanlar ve kürleştiriciler kapsüller içerisine ilave edilmiştir. Geliştirilen bu kendi kendine iyileşebilen kapsüller alüminyum bal peteği sandviç yapı içerisine ilave dilmiştir. Son olarak anlık iyileşme vasfına sahip ultra hızlı kendi kendine iyileşen yapı geliştirilmiştir. Siyanokrilat ajanı ilavesiyle geliştirilen kendi kendine iyileşebilen kapsüllerde hasar sonrası toz aktivatör dolgusuyla otonom iyileşme görülmüştür. Farklı niteliklere sahip yapılardaki kendi kendine iyileşmeler farklı yöntemler ile karakterize edilmiştir. Bu karakterizasyonlar arasında statik bası deneyleri, high strain rate impact deneyleri, penetrasyon deneyleri, spresifik hava ve sıvı deneyleri ve termal kamera analizleri yer almaktadır. Ayrıca dijital mikroskop, optik mikroskop ve SEM görüntüleri ile iyileşmeler görsellenmiştir. Micro and macro damages in self-healing structures can be repaired with healing systems. Thus, the structural integrity of the materials can be preserved and the possibilities of repeated use can be provided. In this study, macrocapsules were developed to repair structural damage. The macrocapsules, approximately 3 mm in diameter, are filled with agents with three different healing abilities. Firstly, the macrocapsules are filled with epoxy resin and curing agents. Damaged capsules were broken and healing was achieved with dispersed agents. Afterwards, polyurethane agents and curing agents with a foaming ability of 17 times by volume were added into the capsules in order to heal the damage geometrically. The developed self-healing capsules are added into the aluminum honeycomb sandwich structure. Finally, an ultra-fast self-healing structure with the instant-healing property was developed. In self-healing capsules developed with the addition of cyanoacrylate agent, autonomous healing was observed with powder activator filling after damage. Self-healing in structures with different qualities has been characterized by different methods. These characterizations include static compression tests, high strain rate impact tests, penetration tests, specific air, liquid tests, and thermal camera analysis. In addition, improvements were visualized with a digital microscope, optical microscope and SEM images. Thus, self-healing has been demonstrated by several different methods.

Introduction: Mercury’s surface is exposed to a multitude of surface altering effects that have a significant influence on its optical properties. Impact events – small or large, are one of the major surface-altering agents. Inferred from hypothetical modal abundances[1] graphite can comprise up to 4wt% on Mercury’s surface. Graphite as a possible stable phase on Mercury can explain the relatively low albedo of the planet[2]. Our experimental setup probes the hypothetical impact into a graphite- and olivine–bearing, pyroxene-rich (Px(En87)=68wt%;Ol(Fo91)=29wt%,C=3wt%) surface. The effect of post-shock heating and pressure on a powder comprised of silicates with grain sizes ≤125 µm and graphite(hexagonal) was simulated in a classic shock recovery experiment[3]. The experiments were performed in the framework of the BepiColombo mission to Mercury. The onboard Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS) will send thermal emissivity data once it reaches the Hermean orbit in 2025. A spectral database for mid infrared data is currently set up at the Institut für Planetologie in Münster. Published mid infrared data will soon be available and sample related spectral information of interest can be traced via assigned IDs (e.g., IDxxx). Experimental set-up and µ-FTIR: One aliquot of the prepared powder mixture served as a blank(ID467) and was not shocked, the second (ID464) aliquot was filled into an ARMCO-Fe container. The cavity (ø=16mm;depth=2mm) that held the powder was lined with tantalum foil (thickness=50 µm) in order to avoid Fe0-metal contamination from the container. Graphite foil particles vary in size (mean=500µm). The foil was cut with a razor to avoid smearing. The calculated peak pressure at the steel/sample interface reached ca. 60 GPa. Pore space was crushed upon impact and contributed to increase the post-shock temperature significantly[4]. Preliminary spectral results were obtained with a Bruker Hyperion 3000. Spectra were measured in reflectance between 3950cm-1-700cm-1. Reflectivity was calculated by measuring a gold standard equaling the sample’s surface roughness. We used a 100x100 µm2 knife edge aperture to limit obtained spectral data from defined regions of interest (ROIs) and integrated over 256 scans to improve the signal/noise ratio. Preliminary spectral results were obtained from both aliquots, ID467 and ID464. ID464 material was extracted from the steel container, from which spectral information were obtained (Fig.1bottom) and are compared to spectral data of the unshocked aliquot (Fig.1top). Figure 1 top&bottom: ID467 spectra(top). Graphite (bright material) embedded in light grey silicate matrix. Areas with indices in micrograph correlate with spectra of same numbering. Yellow highlighted rectangles are magnified for clarity, RBs are labelled and discussed in text. ID464 spectra are plotted below. Pyroxene is dominant in both aliquots. The CF is located at 1187cm-1 in ID464. Both aliquots show comparable reflectance intensities. Yellow arrows denote CO2-related adsorption in ID467. Results and discussion: We observed a dark pumice-like mass protruding perpendicular to the shockwave propagation direction. The center part of the sample shows a glassy luster (e.g.,Fig.2) which is indicative of melt formation. Figure 2: Light microscope image of graphite (dark) embedded in “fluffy”glassy matrix (arrow). Scale bar is 100 µm. ID464 compacted entirely during impact and shows a clearly distinguishable Christiansen feature (CF; a material characteristic reflectance minimum) at 1187cm-1 (similar to CF(En87)=1193cm-1. The CF of ID467 is difficult to determine. The shallowing of the adsorbed CO2-related absorption band[5] at 3677cm-1 steepens the slope towards shorter wavenumbers. Glassy material was identified in many areas. However, crystalline pyroxene surviving the impact is easily distinguished in the electromagnetic range between 1187cm-1-700cm-1, where vibrational normalmodes/or Reststrahlenbands (RBs) of silicates typically occur. RB1 of ID464 (see Fig. 1 bottom) has a shoulder at 1131cm-1, a double peak at 1103cm-1 and 1074cm-1, and another shoulder at 1043cm-1. RBs of both silicate starting materials occur in this range (En87 at 1131cm-1,1107cm-1,and 1056cm-1, and Fo91 at 1063cm-1and 1056cm-1). The envelope of the RB1 region is identical in ID464 and 467, however, a shoulder peak at 1043cm-1 missing in the unshocked, appears in the shocked aliquot and broadens the base of RB1. Pure En87 has a remarkably invariant(energy-wise) RB at 1010cm-1 (ID467) that shifted to 1006cm-1 in ID464. RB3 of the Mg-pyroxene typical “triplet-RBs” (RB3, RB4, RB5 in Fig. 1 top) at 979cm-1 is similarly invariant, however, olivine has a stable RB nearby, at 981cm-1[6]. This band is shifted to a weak shoulder at 973cm-1, either indicating the absence of olivine due to melt formation, or a shock related shift of the En87-associated RB3. Augmenting chemical analyses will help to disambiguate this. Silicate material in direct contact with graphite displays a foam like texture (Fig. 2). Graphite is an excellent thermal conductor. Silicates and graphite have a large density gradient, when shock waves traverse the individual phases, graphite-grains experience significantly higher post-shock temperatures, and thus help in melting the silicate fraction[7]. Shock-related “pumice” pressed toward the outer cylinder margins is dark and has large, entrained cavities. Future chemical and µ-FTIR analyses of the entire ID464 will improve our understanding of how graphite though chemically inert “catalyzes” processes that either not/or insufficiently take place in its absence. This work was funded by the DLR grants 50 QW 1701 and 50 QW 2201A. MERTIS group are A.N.S,A.M,H.H.,I.W.,M.P.R,K.E.B.,J.H.P.,J.H. The authors thank U.Heitmann, F.Spaleck, P.Pelka and M.Artmeier for careful sample and cylinder preparation References: [1] Vander Kaaden & McCubbin (2015), JGR: Planets, 120(2), 195-209 [2] Klima et al. (2018). Geophysical Research Letters, 45(7), 2945-2953. [3] Langenhorst & Deutsch (1994) EPSL, 125(1-4), 407-420. [4] Güldemeister et al. (2013) Meteoritics & Planetary Science, 48(1), 115-133 [5] Bianchi et al. (1994) Applied Catalysis A: General, 112(2), 219-235. [6] Stojic et al. (2021) Icarus, 357, 114162. [7] Moreau & Schwinger (2021) Physics of the Earth and Planetary Interiors, 310, 106630.

Title: Dynamic load during reactive strength tasks Objectives: Objectives were to explore and measure biomechanic parameters of athletes performing different reactive strength tasks using force plates. Methods: 8 male athletes (22,4 ± 1,2 years; 76,3 ± 4,3 kg) took part in experiment. Each of them performed 8 different reactive strength tasks (alternate and single leg bounds, pogo jumps on place, low hurdle jumps, high hurdle jumps 76 cm and 91 cm and long jump take off from 8 and 12 steps approach). Dynamics of tasks was measured using Kistler 9281 EA with sample rate of 1000 Hz. Main observed parameters were maximum vertical force, time to peak force, contact time and impulse. Data were processed in MATLAB R2022a (The MathWorks, Inc. Natick, Massachusetts, USA) and Microsoft Excel 2019. Results: Differences in dynamics of reactive tasks were observed among single leg and double leg exercises. Double leg exercises had much longer time to peak of vertical force than single leg exercises. Biggest vertical forces were observed during single leg bounds, where overload reached seven times body weight. On the other hand lowest peak of vertical force was measured during long jump takeoff from eight steps approach. Maximal forces got higher and contact time shorter with increased approach speed during...

Purpose This paper aims to investigate the issue of performance measurement of social enterprises with main particular focus on economic performance approach reflecting local aspect, since the local aspect plays a significant role in social entrepreneurship concept. Thus, comparison of two instruments that consider local aspects: local multiplier 3 (LM3) and Input-Output analysis is examined. Input-Output analysis is empirically used to calculate social enterprises’ impact on the Czech economy and to confirm the assumption to be more suitable instrument for economic performance measurement of social enterprises in comparison to local multiplier 3 method. Design/methodology/approach The research adopted two-phase approach. At first a qualitative approach was used to compare the two selected instruments (LM3 and Input-Output analysis). Consequently, a quantitative research was applied to determine the impact of social enterprises’ activities on the economies of individual regions. The research was carried out on a sample of social enterprises (143 subjects) in the Czech Republic covering the year 2015. For this approach, Symmetric Input-Output tables and multipliers were calculated and revenue data from each observed social enterprise were used. Findings The findings of the research indicate effects of social enterprises’ activities on the economy in individual regions of the Czech Republic. The results clearly show that the impact of social enterprises on the Czech economy is not negligible. Calculated impacts differ in sectors as well as in regions. Besides, of these findings, the assumption that the Input-Output analysis is more appropriate instrument for economic performance measurement of social enterprises, especially in situation of a larger sample of social enterprises in different regions, in comparison to LM3 method, was confirmed. Research limitations/implications The limitations of this study is the dependence on the Symmetric Input-Output tables, which are usually published by local statistical offices and it takes some time to construct them. A more significant limitation and future research direction relates to the lack of generally accepted measurement framework in the sector of social enterprises and lack of the data, especially quantitative, in the Czech Republic. Practical implications The findings of the research represent a significant contribution to the process chain of understanding the role of social enterprises in (local) economy. The lack of proven impact of social enterprises to economy is considered as important limit of this sector development, not only from the perspective of investors and donors but also from the perspective of policymakers and even social enterprises themselves. The Input-Output analysis can be applied for any region of any country and can contribute to reduce scepticism about economic performance of social enterprises, thus to support putting social and environmental goals of social enterprises into practice. Social implications This research has been carried out on the so far largest identified sample of social enterprises in the Czech Republic and provides data for discourse among stakeholders about social enterprises’ impact; thus, it enables to understand their impact and make capable to enlarge their support network and development. Originality/value This research is a pioneering attempt to provide data about economic impact of social enterprises using Input-Output analysis in the Czech Republic. No previous research identifies such a large sample of Czech social enterprises and collects quantitative data about them, as well as considers Input-Output analysis as an option instead of LM3 method. The effort of this research has been to react on a research gap in studies related to the impact of social enterprises (reflecting local aspect). This paper could be understood as beneficial not only from the perspective of the Czech Republic but also worldwide.

The IMPAKT 2015 Breast Cancer Conference was designed for researchers and clinicians by the Breast International Group (BIG) and the European Society for Medical Oncology (ESMO). The event was held on 7–9 May in Brussels, Belgium, bringing together approximately 525 participants with a special interest in translational science and state-of-the-art applications in the clinical setting. Oncologists, pathologists and scientists collaborated to develop innovative ideas about breast cancer research and to enhance its relevance to patient care. This report highlights the most recent discussions in fundamental research and future clinical perspectives presented by professionals from around the world. It also covers the important issues regarding new technologies for biomarker discovery and the actual path to clinical utility.

In this study load-rate dependent behavior of plain concrete has been investigated by means of numerical methods. To accomplish this, a three dimensional explicit Lagrangian finite element program has been developed for the simulation of contact, impact and fragmentation events based on mixed programming approach. In this respect a graphical user interface (GUI) has been developed using C++ programming language to carry out pre- and post-processing tasks. On the other hand, another program has been developed using FORTRAN programming language to carry out finite element computations. Communication in between GUI and FORTRAN program has been established using standard function import/export mechanism. Microplane material model for concrete has been extended to account for large deformations, rate of loading and thermal effects. Stress locking observed under dominant tensile loading has been addressed by proper relaxation of the kinematical constraint. On the other hand mesh dependency, due to softening behavior present, has been tackled by crack-band regularization. Kinematical contact constraints in normal and tangential directions have been formulated in both total and rate forms. Predictor-corrector type algorithm has been employed as method of constraint enforcement. Requirements for the exact satisfaction of constraints have been discussed. Mohr-Coulomb type frictional constitutive behavior is adopted in tangential direction. Classical radial return mapping algorithm, frequently used for elastic-plastic materials, has been used to perform constitutive update in tangential direction. During high velocity contact-impact events, like projectile penetration, motion function loses its regularity around the impact region due to presence of very large deformations. In order to be able to continue simulations staying within Lagrangian framework, such material is simply removed with a technique based on adaptive element deletion. Maximum principal strain has been used as a deletion criterion. Topological data structures have been implemented to keep track of the evolving contact interface during simulations. Furthermore, to accelerate contact search a procedure based on so-called moving contact sphere has been developed. Predictive capability of the numerical techniques proposed has been assessed by comparisons with some relevant experimental results from literature. Main conclusions have been drawn out and future research directions have been recommended., In Rahmen dieser Arbeit wurde das lastrateabhängige Verhalten von Beton numerisch untersucht. In diesem Zusammenhang wurde ein dreidimensionales lagrangesches Finite-Elemente-Programm für die Simulation von Kontakt- und Impaktverhalten sowie Fragmentierung auf Basis von gemischter Programmierung entwickelt. Unter Anwendung der C++ Programmiersprache wurde eine graphische Oberfläche (GUI) für die Durchführung der Pre- und Post-processing-Aufgaben konzipiert. Ein weiteres Programm wurde für die Finite-Elemente-Berechnungen mit FORTRAN Programmiersprache entwickelt. Die Kommunikation zwischen GUI und FORTRAN-Programm fand durch Standardfunktion Import/Export Mechanismus statt. Das Microplane-Modell für Beton wurde erweitert, um die großen Verformungen, die Belastungsrate und die thermischen Effekte zu berücksichtigen. Das bei der überwiegenden Zugbelastung beobachtete „Stress-locking“ wurde durch eine geeignete Relaxation der kinematischen Bindungen vermieden. Die Netzempfindlichkeit, die Aufgrund der „Softening“ (Erweichung) des Betons entsteht, wurde durch Anwendung der Rissbandmethode berücksichtigt. Kinematische Bindungen für Kontakt in normaler und tangentialer Richtung wurden in absoluter und anteilmäßiger Form formuliert. Ein Prädiktor-Korrektor-Algorithmentyp wurde für die Durchsetzung der Bindungen angewendet. Die Bedingungen für die exakte Erfüllung der Bindungen wurden angesprochen. Das konstitutive Reibungsverhalten des Mohr-Coulomb-Types wurde für die tangentiale Richtung angenommen. Der klassische radiale Rückprojektionsalgorithmus, der oft für elastoplastische Materialen angewendet wird, wurde für die Durchführung der konstitutiven Aktualisierung in tangentialer Richtung eingesetzt. Während der Kontakt–Impakt Hochgeschwindigkeitsereignisse, wie z.B. Geschosspenetration, verliert die Bewegungsfunktion ihre Regelmäßigkeit in der Nähe des Impaktbereiches infolge der großen Verformungen. Um die Simulationen in Rahmen des lagrangeschen Verfahrens fortsetzten zu können, wurde dieses Material gelöscht, wobei eine Technik basierend auf der adaptiven Elementlöschung eingesetzt wurde. Die maximalen Zugdehnungen wurden als Löschkriterium verwendet. Topologische Datenstrukturen wurden implementiert, um den Überblick über die entwickelnde Kontaktschnittstelle in Simulationen zu halten. Darüber hinaus wurde ein Verfahren basierend auf der sogenannten beweglichen Kontaktkugel entwickelt, um die Kontaktsuche zu beschleunigen. Die prädiktive Fähigkeit des vorgeschlagenen numerischen Verfahrens wurde durch Vergleich mit einigen relevanten experimentellen Ergebnissen aus der Literatur untersucht. Die wichtigsten Schlussfolgerungen wurden gezogen und künftige Forschungsrichtungen wurden empfohlen.

In the mountains Hrubý Jeseník was the 18 monitoring plots in the years 2010-2013 conducted tramping of small mammals, inventory damage gnaw the bark of the beech forest plantations and the measured data to investigate the factors influencing the impact of small mammals. Small mammals were then evaluated in terms of dominance, impact on planting and statistically analyzed factors affecting impact. The results show that the dominant group were representatives Arvicolinae (n= 512, 62.4%): Clethrionomys glareolus (n= 306, 37.3%), Microtus agrestis (n= 181, 22.1%), Microtus arvalis (n=23, 2.8%), Microtus subterraneus (n= 2, 0.2%). In terms gnaw the bark of trees to damage most often involved in Microtus agrestis and Microtus arvalis, causing minor damage also Clethrionomys glareolus. Altitude, exposition, composition and character of the herb layer and abundance of voles are significant factors which can affect the impact of small mammals. This information can be useful for forest management, which can reduce the risk of the forest damage occurrence and decrease costs of silvicultural operations.

In Febuary 2013, in spectacular light and sound accompaintmen a meteorite hit the Russian Federation. Small fragment which landed in populated areas caused together with blust wave damage. The largest part broke the ice crust on the lake in outskirts of Chebarkul. The circular shaped hole gave rise to various conspiracy theories. About half of the year after impact the meteorite was lifted and conspiracy theories boken. The event immediately raised interest in the issue of the impacts of meteorites and phenomena associated with them. Processes when the meteor is passing trough atmosphere, impact craters, their origin and characteristics, computer models, types of meteorites and their origin. Or just a mystery of the hole in the ice crust of the lake Chebarkul. Science has got answers for such toppics. This paper is just trying to summarize them.

A complete list of all alien taxa ever recorded in the flora of the Czech Republic is presented as an update of the original checklist published in 2002. New data accumulated in the last decade are incorporated and the listing and status of some taxa are reassessed based on improved knowledge. Alien flora of the Czech Republic consists of 1454 taxa listed with information on their taxonomic position, life history, geographic origin (or mode of origin, distinguishing anecophyte and hybrid), invasive status (casual; naturalized but not invasive; invasive), residence time status (archaeophyte vs neophyte), mode of introduction into the country (accidental, deliberate), and date of the first record. Additional information on species performance that was not part of the previous catalogue, i.e. on the width of species’ habitat niches, their dominance in invaded communities, and impact, is provided. The Czech alien flora consists of 350 (24.1%) archaeophytes and 1104 (75.9%) neophytes. The increase in the total number of taxa compared to the previous catalogue (1378) is due to addition of 151 taxa and removal of 75 (39 archaeophytes and 36 neophytes), important part of the latter being the reclassification of 41 taxa as native, mostly based on archaeobotanical evidence. The additions represent taxa newly recorded since 2002 and reported in the national literature; taxa resulting from investigation of sources omitted while preparing the previous catalogue; redetermination of previously reported taxa; reassessment of some taxa traditionally considered native for which the evidence suggests the opposite; and inclusion of intraspecific taxa previously not recognized in the flora. There are 44 taxa on the list that are reported in the present study for the first time as aliens introduced to the Czech Republic or escaped from cultivation. Práce přináší úplný seznam nepůvodních taxonů zaznamenaných na území České republiky; je aktualizací a doplněním předchozího seznamu publikovaného v roce 2002. Zahrnuje nové údaje shromážděné za poslední desetiletí a přehodnocuje zařazení a status některých druhů, vyplývající z rozvoje taxonomického poznání. Nepůvodní flóra České republiky zahrnuje 1454 taxonů, které jsou uvedeny v Apendixu 2 s informacemi o taxonomické příslušnosti, životní formě, oblasti původu, invazním statusu (zda jde o druh přechodně zavlečený, naturalizovaný avšak neinvazní, nebo invazní), charakteru výskytu v krajině, době zavlečení (archeofyt nebo neofyt), způsobu introdukce do země a u neofytů o datu prvního nálezu. Oproti původnímu katalogu je uveden počet typů biotopů, ve kterých se druh vyskytuje, pokryvnost v rostlinných společenstvech a impakt. Podíl zavlečených druhů v české flóře je značný: tvoří jej 350 (24,1%) archeofytů a 1104 (75.9%) neofytů. Nárůst počtu taxonů oproti původnímu katalogu, který uváděl 1378 taxonů, vyplývá z toho, že bylo přidáno 151 taxonů. Celkem 75 (39 archeofytů a 36 neofytů) bylo naproti tomu vypuštěno; značná část tohoto počtu jde na vrub přeřazení 41 taxonů mezi původní druhy, a to vesměs na základě archeobotanických dokladů. Přírůstky na seznamu představují taxony nově objevené a uvedené v botanické literatuře od roku 2002, taxony zařazené na základě excerpce dříve opominutých zdrojů či revize zdrojů použitých, nebo přehodnocení statusu některých taxonů tradičně považovaných za původní. Vněkterých případech jde o infraspecifické taxony, které nebyly dříve v české flóře rozeznávány. Seznam obsahuje 44 taxonů, které jsou uváděny pro Českou republiku poprvé jako zavlečené, nebo pro něž je podán první důkaz o jejich zplaňování.

The number of real handbooks dealing with lexicography and metalexicography is not, and has never been, impressive. When one looks at comprehensive handbooks and in addition those brought up to date, the number becomes even smaller. Because of this, but also because it has existed for more than 20 years (i.e. in different editions/versions) and because it is — especially in Scandinavia — a quite well-known work, Svensen's handbook is an important publication. In this review article, I will consider what the critics have written over the years (i.e. on the different editions/ versions of Svensen's handbook), and I will attempt to determine whether the book is about to become a classic. OPSOMMING: Meer as twintig jaar van Svensen se handboek. Die aantal werklike handboeke wat die leksikografie en die metaleksikografie behandel, is nie en was nog nooit indrukwekkend nie. Wanneer 'n mens na omvattende handboeke kyk en daarby die wat bygewerk is, word die aantal selfs kleiner. Om die rede, maar ook omdat dit vir meer as 20 jaar bestaan (d.w.s. in verskillende uitgawes/bewerkings) en omdat dit — veral in Skandinawie — 'n redelik welbekende werk is, is Svensen se handboek 'n belangrike publikasie. In hierdie resensieartikel sal ek oorweeg wat die kritici oor die jare geskryf het (d.w.s. oor die verskillende uitgawes/bewerkings van Svensen se handboek), en sal ek probeer bepaal of die boek besig is om 'n klassieke werk te word. Sleutelwoorde: LEKSIKOGRAFIE, METALEKSIKOGRAFIE, HANDBOEKE, VAKKUNDIGE RESENSERING, AANHALINGS, A HANDBOOK OF LEXICOGRAPHY, BO SVENSEN, THE ART AND CRAFT OF LEXICOGRAPHY, SIDNEY I. LANDAU, MANUAL OF LEXICOGRAPHY, LADISLAV ZGUSTA

The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.

The DAISIE project in the 6. framework program of the European Union provides valuable data about European invasive species. Invasive plants have various impacts, positive and negative, and effects all four types of ecosystem services (supporting, provisioning, regulating and cultural). Invasive species are also known to cause serious economic looses. The proposed work aims at summarizing the up-to-date knowledge about the impact of invasive flora on European environment and human well-being. key words: invasive plants, impact, DAISIE, Europe, ecosystem services

In this work the mechanical behaviour of the aluminium alloy AA6060 and the steel 42CrMo4 each of them in two different heat treatment conditions was analysed at quasi-static strain rates up to high dynamic loading at temperatures from RT up to 400°C for the aluminium alloy respectively 800°C for the steel. For the examination of the mechanical behaviour compression tests have been conducted on cylindrical and square-shaped specimens. Both heat treatment conditions of the aluminium alloy AA6060 show just little strain hardening influence and very small adiabatic softening up to high strain rates. But the aluminium alloy shows a quite distinctive temperature dependency that is hardly influenced by the strain rate. At lower temperatures to 200°C there is almost no strain rate dependency detectable up to a strain rate of 100s-1. Above there is partly a negative tendency recognizable before a strong increase in flow stress at high strain rates (>1000s-1). This effect is called “drop-effect”. It was already detected in former studies at similar aluminium alloys. The steel 42CrMo4 in the heat treatment condition 1 (quenching at 850°C, water cooling, quenching at 375°C for 1h) shows nearly no temperature dependency up to 200°C. The influence at higher temperatures gets compensated by the influence of the strain rate that is increasing with the temperature as well. The flow curves at a strain rate of 100s-1 are almost on the same level. In the heat treatment condition 2 (quenching at 850°C, water cooling, quenching at 600°C for 1h) the steel 42CrMo4 shows a little more distinctive temperature dependency but up to a temperature of 400°C there can nearly no influence of the strain rate be found. Above this temperature the flow stress level is continuously rising with the strain rate. Independent from the temperature there is a strong increase concerning the strain rate sensibility above 100s-1. After interpretation of the experimental results an approach for a mathematical description of the flow behaviour of both analysed materials was introduced as well as the development of a material law was explained that contained the influence of the strain, the strain rate and the temperature. Finally the used parameters were determined. For a first validation a simulation model was created afterwards. As material data the developed material law including the appraised parameters were used. The results show a very good conformity between experiments and simulation.

U članku se opisuje "Tunguska eksplozija" koja se dogodila 30.6.1908. a njene su posljedice prepoznate tek desetljećima kasnije. Prikazuju se danas prihvaćena tumačenja eksplozije, i navode se zapažanja nekih očevidaca.

Untersuchung des Verhaltens der Fließspannung und der Verformungsfähigkeit der Titanlegierung Ti-6-22-22S in Abhängigkeit von der Temperatur, der Dehngeschwindigkeit und dem Spannungszustand. Nachweis der thermischen Aktivierung der Versetzungsbewegung bis zu Dehngeschwindigkeiten von 10^5 1/s für diesen Werkstoff. Beschreibung des Versagens als Funktion der Temperatur, der Dehngeschwindigkeit und des Spannungszustandes. Erarbeitung einer Prüfmethode zur Charakterisierung des Scherverhaltens unter hohen überlagerten Druckbelastungen.

Für vier verschiedene Glassorten (K5, F6, SF6 und Floatglas) mit unterschiedlichen physikalischen Eigenschaften wurden die Ausbreitung von Wellen und Zerstörungen bei Impakt mit zylindrischen Stahlprojektilen qualitativ und quantitativ untersucht. Die Zerstörungsgeschwindigkeiten wurden als Funktion der Impaktgeschwindigkeit gemessen und die Nukleationsschwellen bestimmt. Alle vier Gläser zeigen ein ähnliches Verhalten. Die Zerstörung der Proben erfolgt bei niedrigen Belastungen mit maximaler Rißgeschwindigkeit, bei Einsetzen der Nukleation mit transversaler Wellengeschwindigkeit Ct und bei sehr hohen Belastungen mit longitudinaler Wellengeschwindigkeit CL. Dieses Verhalten wurde unabhängig von der Dicke der Proben beobachtet. Ein funktionaler Zusammenhang zwischen der Nukleationsschwelle (sowohl bezüglich der Impaktgeschwindigkeit als auch bezüglich des Impulses, der von der Druckwelle pro Zeiteinheit auf das Target übertragen wird) und der Dicke der Platten konnte nicht festgestellt werden. Die dargestellten Untersuchungen beziehen sich auf die Zerstörung des Targets von dem Eindringen des Projektils. The propagation of waves and damage at impact of cylindrical steel projectiles was investigated qualitatively and quantitatively for four different types of glass (K5, F6, SF6 and float glass). The damage velocities were measured as a function of impact velocity and the threshold for the nucleation of cracks were determined. All four glasses reveal a similar behaviour. The damage velocity equals terminal crack velocity at low loadings, rises to transversal wave velocity when nucleation occurs and approaches longitudinal wave velocity with very high loadings. This behaviour was observed independent of the thickness of the target plates. A functional relation between the thickness of the plates and the threshold of nucleation could not be established, neither with respect to impact velocity nor with respect to the momentum transferred to the target by the pressure wave . The investigations reported here refer to the damage before the projectile penetrates the target.

Four different types of glasses (float glass, optical glasses K5, F6, SF6) were impacted by pointed and blunt projectiles of different diameters within a velocity range from 10 m/s up to 1600 m/s. The propagation of fractures was observed by means of a 24-spark high-speed camera in a shadow-optical arrangement. In addition to the fractures generated at the impacted edge of the glass slabs, crack nuclei were activated by the longitudinal shock wave if the transferred energy was sufficiently high. All types of cracks observed propagated with terminal crack velocity. In order to describe the damage of the targets by the different phenomena, the concept of damage velocity was introduced. Furthermore, a calibre independent representation of the results was found. The fracture and damage velocities in optical glasses with wave speeds between 4500 m/s and 6000 m/s and densities in the range from 2.5 g/cbcm to 5.2 g/cbcm were determined and compared to the results with float glass.

The perforaton process of steel plates at normal impact by cylindrical steel fragments together with the debris cloud expansion have been studied in the velocity range 2 - 3 km/s. The fragments have a length-to-diameter ratio of 1.035 and a mass of 51g. Fragment and target materiass are 9SMn28 and C45, respectively. Two plate thicknesses of 20 and 30 mm have been tested. These thicknesses are in the order of the penetration depth in the semi-infinite target. In addition the cratering in the semi-infinite target has been investigated. The crater dimensions on the target front side are comparable for both, the plate targets and the semi-infinite targets. The degree of fragmentation in the debris cloud increases with velocity and is smaller in case of the 30 mm target. The ratio of longitudinal to lateral dimensions of the debris clouds is independent of the target thickness, but dependent on the distance from the plate rear side. This ratio increases with distance and converges at larger distances versus nearly hemispherical expansion. A further goal of this paper is the application of a Lagrangian code to the numerical simulation of the impact process in the semi-infinite target. For this purpose the LS-DYNA2D code with a new erosion option has been used. Material input data are the static material properties as well as shock wave data determined from planar impact tests for the steels used here. LS-DYNA2D with its new erosion option can predict in a good agreement the particle velocity history of the planar impact tests and the crater shapes in the semi-infinite target.