Ancestral Heaths

Barrows, i.e. burial mounds, are amongst the most important of Europe’s prehistoric monuments. Across the continent, barrows still figure as prominent elements in the landscape. Many of these mounds have been excavated, revealing much about what was buried inside these intriguing monuments. Surprisingly, little is known about the landscape in which the barrows were situated and what role they played in their environment. Palynological data, carrying important clues on the barrow environment, are available for hundreds of excavated mounds in the Netherlands. However, while local vegetation reconstructions from these barrows exist, a reconstruction of the broader landscape around the barrows has yet to be made. This makes it difficult to understand their role in the prehistoric cultural landscape. In this book a detailed vegetation history of the landscape around burial mounds is presented. Newly obtained and extant data derived from palynological analyses taken from barrow sites are (re-)analysed. Methods in barrow palynology are discussed and further developed when necessary. Newly developed techniques are applied in order to get a better impression of the role barrows played in their environment. It is argued in this book that barrows were built on existing heaths, which had been and continued to be maintained for many generations by so-called heath communities. These heaths, therefore, can be considered as ‘ancestral heaths’. The barrow landscape was part of the economic zone of farming communities, while the heath areas were used as grazing grounds. The ancestral heaths were very stable elements in the landscape and were kept in existence for thousands of years. In fact, it is argued that these ancestral heaths were the most important factor in structuring the barrow landscape

Institutional Repositories, Long Term Preservation and the changing nature of Scholarly Publications

In Europe over 2.5 million publications of universities and research institutions are stored in institutional repositories. Although institutional repositories make these publications accessible over time, a repository does not have the task to preserve the content for the long term. Some countries have developed an infrastructure dedicated to sustainability. The Netherlands is one of those countries. The Dutch situation could be regarded as a successful example of how long term preservation of scholarly publications is organised through an open access environment. In this contribution to the Open Repository Conference 2010 it will be explained how this infrastructure is structured, and some preservation issues related to it will be discussed. This contribution is based on the long term preservation studies into Enhanced Publications, performed in the FP7 project DRIVER II (2007-2009, Digital Repository Infrastructure Vision for European Research II, WP 4 Technology Watch Report, part 2, Long-term Preservation Technologies (Deliverable 4.3/Milestone 4.2). http://www.driver-repository.eu/. The official report is downloadable at: http://research.kb.nl/DRIVERII/resources/DRIVER_II_D4_3-M2_demonstrator_LTP__final_1_0_.pdf ; the public version is part of Enhanced Publications : Linking Publications and Research Data in Digital Repositories, by Saskia Woutersen-Windhouwer et al. Amsterdam, AUP, 2009, p. 157-209; downloadable as: http://dare.uva.nl/aup/nl/record/316849). The overall conclusion of the DRIVER studies about long term preservation is that the issues are rather of an organisational nature than of a technical one

Institutional Repositories, Long Term Preservation and the changing nature of Scholarly Publications

In Europe over 2.5 million publications of universities and research institutions are stored in institutional repositories. Although institutional repositories make these publications accessible over time, a repository does not have the task to preserve the content for the long term. Some countries have developed an infrastructure dedicated to sustainability. The Netherlands is one of those countries. The Dutch situation could be regarded as a successful example of how long term preservation of scholarly publications is organised through an open access environment. In this contribution to the Open Repository Conference 2010 it will be explained how this infrastructure is structured, and some preservation issues related to it will be discussed. This contribution is based on the long term preservation studies into Enhanced Publications, performed in the FP7 project DRIVER II (2007-2009, Digital Repository Infrastructure Vision for European Research II, WP 4 Technology Watch Report, part 2, Long-term Preservation Technologies (Deliverable 4.3/Milestone 4.2). http://www.driver-repository.eu/. The official report is downloadable at: http://research.kb.nl/DRIVERII/resources/DRIVER_II_D4_3-M2_demonstrator_LTP__final_1_0_.pdf ; the public version is part of Enhanced Publications : Linking Publications and Research Data in Digital Repositories, by Saskia Woutersen-Windhouwer et al. Amsterdam, AUP, 2009, p. 157-209; downloadable as: http://dare.uva.nl/aup/nl/record/316849). The overall conclusion of the DRIVER studies about long term preservation is that the issues are rather of an organisational nature than of a technical one

Distribution of particles which produces a "smart" material

If $A_q(\beta, \alpha, k)$ is the scattering amplitude, corresponding to a potential $q\in L^2(D)$, where $D\subset\R^3$ is a bounded domain, and $e^{ik\alpha \cdot x}$ is the incident plane wave, then we call the radiation pattern the function $A(\beta):=A_q(\beta, \alpha, k)$, where the unit vector $\alpha$, the incident direction, is fixed, and $k>0$, the wavenumber, is fixed. It is shown that any function $f(\beta)\in L^2(S^2)$, where $S^2$ is the unit sphere in $\R^3$, can be approximated with any desired accuracy by a radiation pattern: $||f(\beta)-A(\beta)||_{L^2(S^2)}<\epsilon$, where $\epsilon>0$ is an arbitrary small fixed number. The potential $q$, corresponding to $A(\beta)$, depends on $f$ and $\epsilon$, and can be calculated analytically. There is a one-to-one correspondence between the above potential and the density of the number of small acoustically soft particles $D_m\subset D$, $1\leq m\leq M$, distributed in an a priori given bounded domain $D\subset\R^3$. The geometrical shape of a small particle $D_m$ is arbitrary, the boundary $S_m$ of $D_m$ is Lipschitz uniformly with respect to $m$. The wave number $k$ and the direction $\alpha$ of the incident upon $D$ plane wave are fixed.It is shown that a suitable distribution of the above particles in $D$ can produce the scattering amplitude $A(\alpha',\alpha)$, $\alpha',\alpha\in S^2$, at a fixed $k>0$, arbitrarily close in the norm of $L^2(S^2\times S^2)$ to an arbitrary given scattering amplitude $f(\alpha',\alpha)$, corresponding to a real-valued potential $q\in L^2(D)$.Comment: corrected typo

Ancestral heaths : reconstructing the barrow landscape in the central and southern Netherlands

Barrows, i.e. burial mounds, are amongst the most important of Europe’s prehistoric monuments. Across Europe, barrows still figure as a prominent element in the landscape. Many barrows in Europe have been excavated, revealing much about what was buried inside these monuments. Little is known, however, about the landscape in which the barrows were situated and what role barrows played in this landscape. Palynological data, carrying important clues on the barrow environment, are absent for most of the excavated barrows in Europe. In the Netherlands however, palynological data are available for hundreds of excavated barrows. However, while local vegetation reconstructions from these barrows are available, a reconstruction of the total landscape around the barrows has yet to made, without which it would be difficult to understand their role in the prehistoric cultural landscape.In this thesis a detailed vegetation history around barrows is reconstructed. Newly obtained and extant data derived from palynological analyses taken from barrow sites have been (re-)analysed. Methods in barrow palynology have been discussed and further developed when necessary and newly developed techniques have been applied in order to get a better impression of what role barrows played in their environment.Barrows were built on ancestral heaths, which were maintained for many generations by heath communities. The barrow landscape was included in the economic zone of farming communities in the area, while the heath areas were used as grazing grounds. The ancestral heaths were very stable elements in the landscape and were kept in existence for thousands of years. In fact, it is argued that these ancestral heaths were the most important factor in structuring the barrow landscape. Paleoecolog

Dynamic spasticity of plantar flexor muscles in cerebral palsy gait

Objective: To quantify dynamic spasticity, i.e. the coupling between muscle-tendon stretch velocity and muscle activity during gait, of the gastrocnemius and soleus muscles in children with spastic cerebral palsy. Design: Prospective, cross-sectional study. Subjects: Seventeen ambulatory children with cerebral palsy with spastic calf muscles, and H matched typically developing children. Methods: The children walked at 3 different speeds. Threedimensional kinematic and electromyographic data were collected. Muscle-tendon velocities of the gastrocnemius medialis and soleus were calculated using musculoskeletal modelling. Results: In typically developing children, muscles were stretched fast in swing without subsequent muscle activity, while spastic muscles were stretched more slowly for the same walking speed, followed by an increase in muscle activity. The mean ratio between peak activity and peak stretch velocity in swing was approximately 4 times higher in spastic muscles, and increased with walking speed. In stance, the stretch of muscles in typically developing children was followed by an increase in muscle activity. Spastic muscles were stretched fast in loading response, but since muscle activity was already built up in swing, no clear dynamic spasticity effect was present. Conclusion: Spastic calf muscles showed increased coupling between muscle-tendon stretch velocity and muscle activity, especially during the swing phase of gait. © 2010 Foundation of Rehabilitation Information

How Crouch Gait Can Dynamically Induce Stiff-Knee Gait

Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on excessive knee muscle activity during (pre)swing, but the passive dynamics of the limbs may also have an important effect. To examine the effects of a crouched posture on swing knee flexion, we developed a forward-dynamic model of human walking with a passive swing knee, capable of stable cyclic walking for a range of stance knee crouch angles. As crouch angle during stance was increased, the knee naturally flexed much less during swing, resulting in a 'stiff-knee' gait pattern and reduced foot clearance. Reduced swing knee flexion was primarily due to altered gravitational moments around the joints during initial swing. We also considered the effects of increased push-off strength and swing hip flexion torque, which both increased swing knee flexion, but the effect of crouch angle was dominant. These findings demonstrate that decreased knee flexion during swing can occur purely as the dynamical result of crouch, rather than from altered muscle function or pathoneurological control alone. © 2010 The Author(s)

De kustbekkens van Zuid-Lazio in de Vroege Bronstijd ten tijde van de Avellino-eruptie (Somma-Vesuvius):een welkome plek of een vijandige omgeving?

Bioarchaeolog