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More and more social interactions happen online. On online social networks such as Instagram, millions of users share, like, and comment on photos and videos every day, interacting with other users world wide, at large scale and at a high rate. These networks do not only introduce new user experiences, but they also enable new insights into human behavior. Here, we use these new possibilities to study homophilic behavior—the tendency of individuals to bond with people similar to themselves. While homophilic behavior has been observed in many contexts, little is known about gender-specific differences and the extent of homophilic behavior of female and male users in online social networks. Based on a unique and extensive data set, covering over 800,000 (directed) Instagram interactions and a time span of three years, we shed light on differences between genders and uncover an intriguing asymmetry of homophily. In particular, we show that female users exhibit homophily to a larger extent than male users. The magnitude of this asymmetry depends on the type of interaction, as differences are more pronounced for 'comment'-interactions than for 'like'-interactions. Given these empirical observations, we further study the implications of such gender differences on the spread of information in social networks in a basic model. We find that on average, a piece of information that originates from a female group reaches significantly more female users than male users. [ABSTRACT FROM AUTHOR]

The structure of the lithosphere is reflecting its evolution. The Moho of the European lithosphere has already been studied intensively. This is, however, not yet the case for the lower boundary of the lithosphere, that is the lithosphere–asthenosphere boundary (LAB). We are using S-to-P converted seismic waves to study the structures of the Moho and the LAB beneath Europe including the greater Alpine Area with data from the AlpArray project and the European networks of permanent seismic stations. We use plain waveform stacking of converted waves without deconvolution and compare the results with stacking of deconvolved traces. We also compare Moho depths determinations using S-to-P converted waves with those obtained by other seismic methods. We present more detailed information about negative velocity gradients (NVG) below the Moho. Its lower bound may be interpreted as representing the LAB. We found that the thickness of the European mantle lithosphere is increasing from about 50°N towards the Alps along the entire east–west extension of the Alps. The NVG has also an east dipping component towards the Pannonian Basin and the Bohemian Massif. The Alps and their northern foreland north of about 50°N are surrounded in the east, west and north by a north dipping mantle lithosphere. Along 50°N, where the NVG is reversing its dip direction towards the north, is also the area along which the volcanoes of the European Cenozoic Rift System are located. Our results possibly indicate that the Alpine collision has deformed the entire lithosphere of the Alpine foreland as far north as about 50°N. [ABSTRACT FROM AUTHOR]

For a fixed j –invariant j 0 of an elliptic curve without complex multiplication we bound the number of j –invariants j that are algebraic units and such that elliptic curves corresponding to j and j 0 are isogenous. Our bounds are explicit. We also modify the problem slightly by fixing a singular modulus α and looking at all j such that |$j-\alpha$| is an algebraic unit and such that elliptic curves corresponding to j and j 0 are isogenous. The number of such j can again be bounded explicitly. [ABSTRACT FROM AUTHOR]

Here we describe the structure, the high-pressure, low-temperature (HP-LT) metamorphism and tectonic evolution of the Briançonnais distal margin units from the south Western Alps. The studied area extends southwest of the Dora-Maira (U)HP basement units and east-southeast of the classical Briançonnais nappes. A new structural map accompanied by geological profiles shows the thrusting of the oceanic nappes (Monviso and Queyras units) onto the distal Briançonnais units (D1 and D2 late Eocene deformation phases) under blueschist-facies conditions. Subsequent deformation during the Early Oligocene (D3 deformation phase) took place under greenschist-facies conditions and was associated with back-folding and -thrusting in the units overlying the Dora-Maira massif and with exhumation related to normal reactivation of former thrusts within the latter massif. Two large cover units, detached from their former distal Briançonnais basement, are redefined as the Maira-Sampeyre and Val Grana Allochthons (shortly: Maira-Grana Allochthons = MGA) including, (i) the Val Maira-Sampeyre unit involving Lower and Middle Triassic formations, seemingly detached from the Dora-Maira units during the subduction process, and (ii) the Val Grana unit with Middle-Upper Triassic and Early-Middle Jurassic formations, which was probably detached from the Maira-Sampeyre unit and correlates with the "Prepiemonte units" known from the Ligurian Alps to the Swiss Prealps. Three major shear zones involving tectonic mélanges of oceanic and continental rocks at the base of the Val Grana, Maira-Sampeyre and Dronero units testify to an early phase of exhumation within the subduction channel in front of the Adria plate. We present a new metamorphic map based on published and new petrological data, including new thermometric data obtained by Raman spectroscopy of carbonaceous material (RSCM). The TRSCM values range from ~ 400 °C to > 500 °C, going from the most external Val Grana unit and overlying Queyras schists to the uppermost Dora-Maira unit. During the Late Triassic, the width of the Briançonnais s.l. domain can be restored at ~ 100 km, whereas it reached ~ 150 km after the Jurassic rifting. A significant, second rifting event affected the Briançonnais domain during the Late Cretaceous-Paleocene, forming the Longet-Alpet chaotic breccias, which deserve further investigations. [ABSTRACT FROM AUTHOR]

We consider a natural problem dealing with weighted packet selection across a rechargeable link, which e.g., finds applications in cryptocurrency networks. The capacity of a link (u , v) is determined by how many nodes u and v allocate for this link. Specifically, the input is a finite ordered sequence of packets that arrive in both directions along a link. Given (u , v) and a packet of weight x going from u to v , node u can either accept or reject the packet. If u accepts the packet, the capacity on link (u , v) decreases by x. Correspondingly, v 's capacity on (u , v) increases by x. If a node rejects the packet, this will entail a cost affinely linear in the weight of the packet. A link is "rechargeable" in the sense that the total capacity of the link has to remain constant, but the allocation of capacity at the ends of the link can depend arbitrarily on the nodes' decisions. The goal is to minimise the sum of the capacity injected into the link and the cost of rejecting packets. We show that the problem is NP-hard, but can be approximated efficiently with a ratio of (1 + ε) ⋅ (1 + 3) for some arbitrary ε > 0. [ABSTRACT FROM AUTHOR]

Here we describe the structure, the high-pressure, low-temperature (HP-LT) metamorphism and tectonic evolution of the Briançonnais distal margin units from the south Western Alps. The studied area extends southwest of the Dora-Maira (U)HP basement units and east-southeast of the classical Briançonnais nappes. A new structural map accompanied by geological profiles shows the thrusting of the oceanic nappes (Monviso and Queyras units) onto the distal Briançonnais units (D1 and D2 late Eocene deformation phases) under blueschist-facies conditions. Subsequent deformation during the Early Oligocene (D3 deformation phase) took place under greenschist-facies conditions and was associated with back-folding and -thrusting in the units overlying the Dora-Maira massif and with exhumation related to normal reactivation of former thrusts within the latter massif. Two large cover units, detached from their former distal Briançonnais basement, are redefined as the Maira-Sampeyre and Val Grana Allochthons (shortly: Maira-Grana Allochthons = MGA) including, (i) the Val Maira-Sampeyre unit involving Lower and Middle Triassic formations, seemingly detached from the Dora-Maira units during the subduction process, and (ii) the Val Grana unit with Middle-Upper Triassic and Early-Middle Jurassic formations, which was probably detached from the Maira-Sampeyre unit and correlates with the “Prepiemonte units” known from the Ligurian Alps to the Swiss Prealps. Three major shear zones involving tectonic mélanges of oceanic and continental rocks at the base of the Val Grana, Maira-Sampeyre and Dronero units testify to an early phase of exhumation within the subduction channel in front of the Adria plate. We present a new metamorphic map based on published and new petrological data, including new thermometric data obtained by Raman spectroscopy of carbonaceous material (RSCM). The TRSCM values range from ~ 400 °C to > 500 °C, going from the most external Val Grana unit and overlying Queyras schists to the uppermost Dora-Maira unit. During the Late Triassic, the width of the Briançonnais s.l. domain can be restored at ~ 100 km, whereas it reached ~ 150 km after the Jurassic rifting. A significant, second rifting event affected the Briançonnais domain during the Late Cretaceous-Paleocene, forming the Longet-Alpet chaotic breccias, which deserve further investigations. [ABSTRACT FROM AUTHOR]

Based on recent results of AlpArray, we propose a new model of Alpine collision that involves subduction and detachment of thick (∼ 180 km) European lithosphere. Our approach combines teleseismic P-wave tomography and existing local earthquake tomography (LET), allowing us to image the Alpine slabs and their connections with the overlying orogenic lithosphere at an unprecedented resolution. The images call into question the conventional notion that downward-moving lithosphere and slabs comprise only seismically fast lithosphere. We propose that the European lithosphere is heterogeneous, locally containing layered positive and negative Vp anomalies of up to 5 %–6 %. We attribute this layered heterogeneity to seismic anisotropy and/or compositional differences inherited from the Variscan and pre-Variscan orogenic cycles rather than to thermal anomalies. The lithosphere–asthenosphere boundary (LAB) of the European Plate therefore lies below the conventionally defined seismological LAB. In contrast, the lithosphere of the Adriatic Plate is thinner and has a lower boundary approximately at the base of strong positive Vp anomalies at 100–120 km. Horizontal and vertical tomographic slices reveal that beneath the central and western Alps, the European slab dips steeply to the south and southeast and is only locally still attached to the Alpine lithosphere. However, in the eastern Alps and Carpathians, this slab is completely detached from the orogenic crust and dips steeply to the north to northeast. This along-strike change in attachment coincides with an abrupt decrease in Moho depth below the Tauern Window, the Moho being underlain by a pronounced negative Vp anomaly that reaches eastward into the Pannonian Basin area. This negative Vp anomaly is interpreted as representing hot upwelling asthenosphere that heated the overlying crust, allowing it to accommodate Neogene orogen-parallel lateral extrusion and thinning of the ALCAPA tectonic unit (upper plate crustal edifice of Alps and Carpathians) to the east. A European origin of the northward-dipping, detached slab segment beneath the eastern Alps is likely since its down-dip length matches estimated Tertiary shortening in the eastern Alps accommodated by originally south-dipping subduction of European lithosphere. A slab anomaly beneath the Dinarides is of Adriatic origin and dips to the northeast. There is no evidence that this slab dips beneath the Alps. The slab anomaly beneath the Northern Apennines, also of Adriatic origin, hangs subvertically and is detached from the Apenninic orogenic crust and foreland. Except for its northernmost segment where it locally overlies the southern end of the European slab of the Alps, this slab is clearly separated from the latter by a broad zone of low Vp velocities located south of the Alpine slab beneath the Po Basin. Considered as a whole, the slabs of the Alpine chain are interpreted as highly attenuated, largely detached sheets of continental margin and Alpine Tethyan oceanic lithosphere that locally reach down to a slab graveyard in the mantle transition zone (MTZ). [ABSTRACT FROM AUTHOR]

In the frame of the AlpArray project we analyse teleseismic data from permanent and temporary stations of the Alpine region to study seismic discontinuities down to about 140 km depth. We average broadband teleseismic S-waveform data to retrieve S-to-P converted signals from below the seismic stations. In order to avoid processing artefacts, no deconvolution or filtering is applied, and S arrival times are used as reference for stacking. We show a number of north–south and east-west profiles through the Alpine area. The Moho signals are always seen very clearly, and negative velocity gradients below the Moho depth are also visible in a number of profiles. A Moho depression is visible along larger parts of the Alpine chain. It reaches its largest depth of 60 km beneath the Tauern Window. However, the Moho depression ends abruptly near about 13 ∘ E below the eastern Tauern Window. This Moho depression may represent the crustal trench, where the Eurasian lithosphere is subducted below the Adriatic lithosphere. East of 13 ∘ E an important along-strike change occurs; the image of the Moho changes completely. No Moho deepening is found in this easterly region; instead the Moho bends up along the contact between the European and the Adriatic lithosphere all the way to the Pannonian Basin. An important along-strike change was also detected in the upper mantle structure at about 14 ∘ E. There, the lateral disappearance of a zone of negative velocity gradient in the uppermost mantle indicates that the S-dipping European slab laterally terminates east of the Tauern Window in the axial zone of the Alps. The area east of about 13 ∘ E is known to have been affected by severe late-stage modifications of the structure of crust and uppermost mantle during the Miocene when the ALCAPA (Alpine, Carpathian, Pannonian) block was subject to E-directed lateral extrusion. [ABSTRACT FROM AUTHOR]

For each algebraic number α ∈ ℚ ̄ , a result of Habegger [P. Habegger, Singular moduli that are algebraic units, Algebra Number Theory 9(7) (2015) 1515–1524] shows that there are only finitely many singular moduli j such that j − α is an algebraic unit. His result uses Duke's Equidistribution Theorem and is thus not effective. In this paper, we give an effective proof of Habegger's result assuming that α is not a singular modulus itself. We give an explicit bound, which depends only on α , on the discriminant Δ associated with a singular modulus j such that j − α is a unit. This implies explicit bounds on the number of these singular moduli. [ABSTRACT FROM AUTHOR]

Abstract: There is a long-held belief that physical activities such as lifting with a flexed spine is generally harmful for the back and can cause low back pain (LBP), potentially reinforcing fear-avoidance beliefs underlying pain-related fear. In patients with chronic LBP, pain-related fear has been shown to be associated with reduced lumbar range of motion during lifting, suggesting a protective response to pain. However, despite short-term beneficial effects for tissue health, recent evidence suggests that maintaining a protective trunk movement strategy may also pose a risk for (persistent) LBP due to possible pronociceptive consequences of altered spinal motion, potentially leading to increased loading on lumbar tissues. Yet, it is unknown if similar protective movement strategies already exist in pain-free individuals, which would yield potential insights into the role of fear-avoidance beliefs in motor behavior in the absence of pain. Therefore, the aim of this study is to test whether fear-avoidance beliefs influence spinal motion during lifting in a healthy cohort of pain-free adults without a history of chronic pain. The study subjects (N = 57) filled out several pain-related fear questionnaires and were asked to perform a lifting task (5kg-box). High-resolution spinal kinematics were assessed using an optical motion capturing system. Time-sensitive analyses were performed based on statistical parametric mapping. The results demonstrated time-specific and negative relationships between self-report measures of pain-related fear and lumbar spine flexion angles during lifting, indicating potential unfavorable interactions between psychological factors and spinal motion during lifting in pain-free subjects. [ABSTRACT FROM AUTHOR]

Based on recent results of AlpArray, we propose a new model of Alpine collision that involves subduction and detachment of thick (180-200 km) European tectosphere. Our approach combines teleseismic P-wave tomography and existing Local Earthquake Tomography (LET) allowing us to image the Alpine slabs and their connections with the overlying orogenic crust at an unprecedented resolution. The images call into question the conventional notion that slabs comprise only seismically fast lithosphere and suggest that the mantle of the downgoing European Plate is heterogeneous, containing both positive and negative Vp anomalies of up to 5-6%. We interpret these as compositional rather than thermal anomalies, inherited from the Variscan and pre-Variscan orogenic cycles. They make up a kinematic entity referred to as tectosphere, which presently dips beneath the Alpine orogenic front. In contrast to the European Plate, the tectosphere of the Adriatic Plate is thinner (100-120 km) and has a lower boundary approximately at the interface between positive and negative Vp anomalies. Horizontal and vertical tomographic slices reveal that beneath the Central and Western Alps, the downgoing European tectospheric slab dips steeply to the S and SE and is only locally still attached to the Alpine crust. However, in the Eastern Alps and Carpathians, the European slab is completely detached from the orogenic crust and dips steeply to the N-NE. This along-strike change in attachment coincides with an abrupt decrease in Moho depth below the Tauern Window, the Moho being underlain by a pronounced negative Vp anomaly that reaches eastward into the Pannonian Basin area. This negative Vp anomaly is interpreted to represent hot upwelling asthenosphere that was instrumental in accommodating Neogene orogen-parallel lateral extrusion of the ALCAPA tectonic unit (upper plate crustal edifice of Alps and Carpathians) to the east. A European origin of the northward-dipping, detached slab segment beneath the Eastern Alps is likely since its imaged down-dip length (300-500 km) matches estimated Tertiary shortening in the Eastern Alps accommodated by south-dipping subduction of European tectosphere. A slab anomaly beneath the Dinarides is of Adriatic origin and dips to the northeast. There is no evidence that this slab dips beneath the Alps. The slab anomaly beneath the northern Apennines, also of Adriatic origin, hangs subvertically and is detached from the Apenninic orogenic crust and foreland. Except for its northernmost segment where it locally overlies the southern end of the European slab of the Alps, this slab is clearly separated from the latter by a broad zone of low Vp velocities located south of the Alpine slab beneath the Po Basin. Considered as a whole, the slabs of the Alpine chain are interpreted as attenuated, largely detached sheets of continental margin and Alpine Tethyan lithosphere that locally reach down to a slab graveyard in the Mantle Transition Zone (MTZ). [ABSTRACT FROM AUTHOR]

In the frame of the AlpArray project we analyze teleseismic data from permanent and temporary stations of the greater Alpine region to study seismic discontinuities down to about 140 km depth. We average broadband teleseismic S waveform data to retrieve S-to-P converted signals from below the seismic stations. In order to avoid processing artefacts, no deconvolution or filtering is applied and S arrival times are used as reference. We show a number of north-south and east-west profiles through the greater Alpine area. The Moho signals are always seen very clearly, and also negative velocity gradients below the Moho are visible in a number of profiles. A Moho depression is visible along larger parts of the Alpine chain. It reaches its largest depth of 60 km beneath the Tauern Window. The Moho depression ends however abruptly near about 13° E below the eastern Tauern Window. The Moho depression may represent the mantle trench, where the Eurasian lithosphere is subducted below the Adriatic lithosphere. East of 13° E an important along-strike change occurs; the image of the Moho changes completely. No Moho deepening is found in this easterly region; instead the Moho is updoming along the contact between the European and the Adriatic lithosphere all the way into the Pannonian Basin. An important along strike change was also detected in the upper mantle structure at about 14° E. There, the lateral disappearance of a zone of negative P-wave velocity gradient indicates that the S-dipping European slab laterally terminates east of the Tauern Window in the axial zone of the Alps. The area east of about 13° E is known to have been affected by severe late-stage modifications of the structure of crust and uppermost mantle during the Miocene when the ALCAPA (Alpine, Carpathian, Pannonian) block was subject to E-directed lateral extrusion. [ABSTRACT FROM AUTHOR]

• Advancing deep earth imaging with short-period body waves from ambient noise. • Novel and efficient strategy for retrieving deep-path body waves from ambient noise. • Unveiling the mantle transition zone structure in South-Central Europe: a fresh perspective. We map the mantle transition zone (MTZ) discontinuities beneath South-Central Europe using P-wave reflection phases recovered from noise correlations. We analyze up to four years of seismic noise recordings from 900 broadband stations in the study area. By stacking noise correlations in selected summer months, we significantly improved the retrieval of typically low-amplitude body-wave reflection phases in the light of a quiet surface-wave environment and sufficient noise body-wave illumination from deep paths. We obtain reliable P-wave reflections associated with the 410 km and 660 km discontinuities in the period band of 4–10 s. These short-period reflections reveal clear lateral depth variations of the two discontinuities, indicating complex MTZ structure under the greater Alpine region. This provides new important constraints on present and past mantle dynamics, and it shows the strong potential of passive seismic imaging for studying deep-Earth discontinuities. [ABSTRACT FROM AUTHOR]

Background: Regular infant carrying might be a contributing factor for the development and progression of low back and pelvic girdle pain in mothers after childbirth. However, the neuromechanical adaptations of the spine due to different sling-based carrying techniques are not sufficiently well understood in order to provide evidence-based carrying recommendations.Research Question: What are the immediate effects of different sling-based infant carrying techniques on trunk neuromechanics?Methods: Using a Vicon motion capture and a wireless surface electromyography system, three-dimensional pelvis and spinal kinematics as well as activation patterns of eight trunk muscles were derived from fifteen healthy young women during upright standing and level walking without carrying a load and while carrying a 6 kg-dummy with a sling in front and on either side. Data were analyzed using Statistical Parametric Mapping, allowing group comparisons of discrete parameters (standing) as well as continuous data (walking). To distinguish between clinically relevant and clinically not relevant kinematic findings, statistically significant differences were only considered in case of ≥5°.Results: Compared to unloaded walking, carrying the dummy in front was mainly associated with increased lumbar lordosis (standing: (Δ8.8°, p = 0.006; walking: (Δ ≥ 8.2°, 1-100% of gait cycle [%GC], p < 0.001). When carrying the dummy on the preferred side, increased thoracic kyphosis (standing: ≥6.4°, p ≤ 0.003; walking: Δ ≥ 5.6°, 1-100%GC, p < 0.001) and axial rotation towards the ipsilateral side (standing: Δ5.3°, p = 0.003; walking: Δ ≥ 5.0°, 46-58%GC, p = 0.002) were observed. All three conditions entailed increased paraspinal muscle activity during walking, although only unilaterally in side carrying (lumbar, preferred condition: Δ ≥ 13.2%maxMVIC, 49-57%GC, p < 0.001; thoracic, non-preferred condition: Δ ≥ 5.3%maxMVIC, 47-58%GC, p < 0.001).Significance: Carrying an infant alternating on both sides using a sling could be advantageous for preventing musculoskeletal pain resulting from excessive lumbar hyperextension and paraspinal muscle hyperactivation in women after childbirth. [ABSTRACT FROM AUTHOR]

Aim: Generalized joint hypermobility (GJH) is a frequent entity, which is still not fully understood. Symptoms associated with GJH are musculoskeletal disorders, decreased balance, impaired proprioception and chronic pain. The purpose of this study was to compare the passive anterior tibial translation (TT) in terms of distance and corresponding force between normomobile (NM) and hypermobile (HM) as well as between NM, symptomatic (HM‐s) and asymptomatic (HM‐as) hypermobile women. Methods: A total of 195 women, 67 NM and 128 HM, whereof 56 were further classified as HM‐s and 47 as HM‐as, participated in this study. Passive TT was measured using an adapted Rolimeter. A manual traction force was applied and the distance of the translation measured. For the analysis, maximal translation (TTmax) and the respective force as well as the distance at 40N (TTF40) and 80N (TTF80) traction force were determined. The NM and HM groups were compared using independent samples t‐tests, whereas the NM, HM‐s and HM‐as groups were compared using one‐way analyses of variance with Tukey post hoc tests (significance level P ≤ 0.05). Results: Comparisons revealed higher values for the variables TTmax, TTF40 and TTF80 in the HM compared to the NM group. In addition, TTmax and TTF80 were found to be higher in the HM‐s compared to the NM group. Conclusions: HM women showed significantly higher TT distances, which were even more accentuated in those having symptoms. The findings point toward less passive stability of the knee joint and thus maybe a need of higher muscle activation in order to stabilize the joint. [ABSTRACT FROM AUTHOR]

Introduction. Stochastic resonance whole-body vibration (SR-WBV) devices are promising sensorimotor interventions to address muscle weakness and to improve balance and mobility particularly in the elderly. However, it remains inconclusive whether individuals with stroke or traumatic brain injury (TBI) can profit from this method. The aim of this prospective single-blind randomized controlled trial was to investigate the effects of SR-WBV on muscle strength as well as gait and balance performance in this population. Methods. Forty-eight individuals with stroke or TBI were randomly allocated to an experimental and a sham group. Participants were exposed daily to 5 consecutives 1-minute SR-WBV sessions, whereas the experimental group trained in a standing position with 5 Hz and the sham group in a seated position with 1 Hz. Isometric muscle strength properties of the paretic knee extensor muscles as well as balance and gait performance were measured at baseline, after the first session and after two weeks of SR-WBV. Results. Both groups showed short- and long-term effects in gait performance. However, no between-group effects could be found at the three measurement points. Discussion. Complementary SR-WBV showed no beneficial effects immediately after the intervention and after two weeks of conventional rehabilitation therapy. Future research is needed to identify the potential efficacy of SR-WBV in individuals with stroke and TBI using shorter and less exhausting test procedures and a generally prolonged intervention time. [ABSTRACT FROM AUTHOR]

This contribution analyses the structural architecture and tectono-metamorphic evolution of Briançonnais units in the southern French-Italian Western Alps. The studied area extends from a virtually non-metamorphic area adjacent to the Helvetic-Dauphinois External Domain in the west to the Monviso-Queyras ocean-derived units in the east, where metamorphism increases up to eclogite-facies. Mapping at the scale 1:10.000 of a mountainous part of the Ubaye-Maira transect was performed, which portrays in detail the Briançonnais units over ~ 100 km2. The lithologies include meta-andesite, meta-siliciclastics, marbles, turbiditic calcschists and flysch whose age spans from Late Carboniferous to Eocene. Metamorphism is low-grade greenschist-facies in the west but reaches the blueschist-facies to the east. Structures related to four phases of deformation are identified. The first two generations of structures (D1–D2), related to the original top-to-the-west nappe stacking, are associated with conditions close to the peak of Alpine metamorphism. Previous tectonic surfaces are transposed by the dominant deformation structures (D3), developed under retrograde/decompression conditions. This D3 corresponds to a backfolding and back-thrusting event with a top-to-the-E transport. A fourth phase (D4) developed during late low-grade metamorphic conditions and deforms the previous surfaces by locally developing a crenulation cleavage, followed by brittle tectonics. An updated metamorphic map is presented, backed on published estimates and new thermometric data obtained by Raman Spectroscopy of Carbonaceous Material (RSCM). The TRSCM values range from ~ 295 °C to > 350 °C, moving from the most external Briançonnais unit to the internal Queyras "Schistes Lustrés" units. Suspected Upper Cretaceous palaeofaults have been documented, allowing us to group the classic Aiguille de Mary and Ceillac (sub-) units into a single tectonic unit, here referred to as Maurin unit. The palaeogeographical reconstruction of the evolution of the studied transect highlights the importance of the Marinet and Maurin axial units in the feeding of the Late Cretaceous-Eocene breccias deposited on the more internal Acceglio-type units. [ABSTRACT FROM AUTHOR]

The construction of five crustal-scale profiles across the Western Alps and the Ivrea mantle wedge integrates up-to-date geological and geophysical information and reveals important along strike changes in the overall structure of the crust of the Western Alpine arc. Tectonic analysis of the profiles, together with a review of the existing literature allows for proposing the following multistage evolution of the arc of the Western Alps: (1) exhumation of the mantle beneath the Ivrea Zone to shallow crustal depths during Mesozoic is a prerequisite for the formation of a strong Ivrea mantle wedge whose strength exceeds that of surrounding mostly quartz-bearing units, and consequently allows for indentation of the Ivrea mantle wedge and eastward back-thrusting of the western Alps during Alpine orogeny. (2) A first early stage (pre-35 Ma) of the West-Alpine orogenic evolution is characterized by top-NNW thrusting in sinistral transpression causing at least some 260 km displacement of internal Western Alps and E-W-striking Alps farther east, together with the Adria micro-plate, towards N to NNW with respect to stable Europe. (3) The second stage (35-25 Ma), further accentuating the arc, is associated with top-WNW thrusting in the external zones of the central portion of the arc and is related to the lateral indentation of the Ivrea mantle slice towards WNW by some 100-150 km. (4) The final stage of arc formation (25-0 Ma) is associated with orogeny in the Apennines leading to oroclinal bending in the southernmost Western Alps in connection with the 50° counterclockwise rotation of the Corsica-Sardinia block and the Ligurian Alps. Analysis of existing literature data on the Alps-Apennines transition zone reveals that substantial parts of the Northern Apennines formerly suffered Alpine-type shortening associated with an E-dipping Alpine subduction zone and were backthrusted to the NE during Apenninic orogeny that commences in the Oligocene. [ABSTRACT FROM AUTHOR]

Background and Purpose: Foot equinus and leg length discrepancy (LLD) are common problems in hemiplegic cerebral palsy (hCP), both causing secondary deviations of pelvic motion during gait. It can therefore be assumed that the spinal deviations observed in hCP patients are secondary as a compensation for the position of the pelvis arising from the disturbed leg function. This study investigated the effects of correcting lower extremity function by orthotics on spinal gait kinematics in hCP patients.Methods: Ten adolescent hCP patients and 15 healthy controls were included. Using a validated and previously used enhanced marker set, sagittal and frontal plane spinal curvature angles as well as general trunk and lower extremity kinematics were measured while walking barefoot as well as with an orthotic correction (only hCP patients) using a 12-camera motion capture system.Results: The hCP patients in both the barefoot and orthotic conditions indicated clinically relevant greater lumbar lordosis angles (d≥0.96, p≤0.071), smaller thoracic kyphosis angles (d≥0.84, p≤0.142) and differences in frontal plane lumbar curvature angles (d≥1.00, p≤0.105) compared to controls. However, these angles were not influenced by the successful restoration of a normal heel-to-toe gait pattern and the correction of any LLD using lower extremity orthotics.Conclusions: Spinal gait deviations in adolescents with mild hCP seemed not to result secondarily from foot equinus or LLD, but probably from structural deformities such as hip flexor contractures. Future research should address long-term effects of an AFO treatment as well as the relationship between spinal kinematics and severity of disease. [ABSTRACT FROM AUTHOR]

Powerline communication networks assume an interesting position in the communication network space: similarly to wireless networks, powerline networks are based on a shared broadcast medium; unlike wireless networks, however, the signal propagation is constrained to the power lines of the electrical infrastructure, which is essentially a graph. This article presents an algorithmic model to study the design of communication services over powerline communication networks. As a case study, we focus on the fundamental broadcast problem, and present and analyze a distributed algorithm $$\textsc {Color}\textsc {Cast}$$ which terminates in at most n communication rounds, where n denotes the network size, even in a model where link qualities are unpredictable and time-varying. For comparison, the achieved broadcast time is lower than what can be achieved by any unknown-topology algorithm (lower bounds $$\varOmega (n\log n / \log (n/D))$$ and $$\varOmega (n \log D)$$ are proved in Kowalski and Pelc (Distrib Comput 18(1):43-57, ) resp. Clementi et al. () where D is the network diameter). Moreover, existing known-topology broadcast algorithms often fail to deliver the broadcast message entirely in this model. This article also presents a general broadcast lower bound for the powerline model. [ABSTRACT FROM AUTHOR]

The article presents the discussion on Mark R. Handy's contributions to geoscience being multi-faceted in terms of research activities including latest activities centred at building a bridge between geophysics and the rest of the solid earth science community.

Background and Purpose: The pathogenesis of adolescent idiopathic scoliosis (AIS) remains poorly understood. Previous research has indicated possible relationships between kinematics of the spine, pelvis and lower extremities during gait and the progression of AIS, but adequate evidence on spinal kinematics is lacking. The aim of this study was to provide a detailed assessment of spinal gait kinematics in AIS patients compared to asymptomatic controls.Methods: Fourteen AIS patients and 15 asymptomatic controls were included. Through introducing a previously validated enhanced trunk marker set, sagittal and frontal spinal curvature angles as well as general trunk kinematics were measured during gait using a 12-camera Vicon motion capture system. Group comparisons were conducted using T-tests and relationships between kinematic parameters and severity of scoliosis (Cobb angle) were investigated using regression analyses.Results: The sagittal thoracic curvature angle in AIS patients showed on average 10.7° (4.2°, 17.3°) less kyphosis but 4.9° (2.3°, 7.6°) more range of motion (Cobb angle-dependent (R(2)=0.503)). In the frontal plane, thoracic and thoracolumbar/lumbar curvature angles indicated average lateral deviations in AIS patients. General trunk kinematics and spatio-temporal gait parameters, however, did not show any clinically relevant differences between the groups.Conclusions: This demonstrates that the dynamic functionality of the scoliotic spine can be assessed using advanced non-invasive optical approaches and that these should become standard in clinical gait analysis. Furthermore, curvature angle data might be used to drive sophisticated computer simulation models in order to gain an insight into the dynamic loading behavior of the scoliotic spine during gait. [ABSTRACT FROM AUTHOR]

Background and Purpose: Although the relevance of understanding spinal kinematics during functional activities in patients with complex spinal deformities is undisputed among researchers and clinicians, evidence using skin marker-based motion capture systems is still limited to a handful of studies, mostly conducted on healthy subjects and using non-validated marker configurations. The current study therefore aimed to explore the validity of a previously developed enhanced trunk marker set for the static measurement of spinal curvature angles in patients with main thoracic adolescent idiopathic scoliosis. In addition, the impact of inaccurate marker placement on curvature angle calculation was investigated. Methods: Ten patients (Cobb angle: 44.4±17.7 degrees) were equipped with radio-opaque markers on selected spinous processes and underwent a standard biplanar radiographic examination. Subsequently, radio-opaque markers were replaced with retro-reflective markers and the patients were measured statically using a Vicon motion capture system. Thoracolumbar / lumbar and thoracic curvature angles in the sagittal and frontal planes were calculated based on the centers of area of the vertebral bodies and radio-opaque markers as well as the three-dimensional position of the retro-reflective markers. To investigate curvature angle estimation accuracy, linear regression analyses among the respective parameters were used. The impact of inaccurate marker placement was explored using linear regression analyses among the radio-opaque marker- and spinous process-derived curvature angles. Results and Discussion: The results demonstrate that curvatures angles in the sagittal plane can be measured with reasonable accuracy, whereas in the frontal plane, angles were systematically underestimated, mainly due to the positional and structural deformities of the scoliotic vertebrae. Inaccuracy of marker placement had a greater impact on thoracolumbar / lumbar than thoracic curvature angles. It is suggested that spinal curvature measurements are included in marker-based clinical gait analysis protocols in order to enable a deeper understanding of the biomechanical behavior of the healthy and pathological spine in dynamic situations as well as to comprehensively evaluate treatment effects. [ABSTRACT FROM AUTHOR]

Musculoskeletal models have the potential to improve diagnosis and optimize clinical treatment by predicting accurate outcomes on an individual basis. However, the subject-specific modeling of spinal alignment is often strongly simplified or is based on radiographic assessments, exposing subjects to unnecessary radiation. We therefore developed and introduced a novel skin marker-based approach for modeling subject-specific spinal alignment and evaluated its feasibility by comparing the predicted L1/L2 spinal loads during various functional activities with the loads predicted by the generically scaled models as well as with in vivo measured data obtained from the OrthoLoad database. Spinal loading simulations resulted in considerably higher compressive forces for both scaling approaches over all simulated activities, and AP shear forces that were closer or similar to the in vivo data for the subject-specific approach during upright standing activities and for the generic approach during activities that involved large flexions. These results underline the feasibility of the proposed method and associated workflow for inter- and intra-subject investigations using musculoskeletal simulations. When implemented into standard model scaling workflows, it is expected to improve the accuracy of muscle activity and joint loading simulations, which is crucial for investigations of treatment effects or pathology-dependent deviations. [ABSTRACT FROM AUTHOR]

Network virtualization is a new Internet paradigm which allows multiple virtual networks (VNets) to share the resources of a given physical infrastructure. The virtualization of entire networks is the natural next step after the virtualization of nodes and links. While the problem of how to embed a VNet ('guest network') on a given resource network ('host network') is algorithmically well-understood, much less is known about the security implications of this new technology. This paper introduces a new model to reason about one particular security threat: the leakage of information about the physical infrastructure-often a business secret. We initiate the study of this new problem and introduce the notion of request complexity which describes the number of VNet requests needed to fully disclose the substrate topology. We derive lower bounds and present algorithms achieving an asymptotically optimal request complexity for important graph classes such as trees, cactus graphs (complexity $$O(n)$$ ) as well as arbitrary graphs (complexity $$O(n^2)$$ ). Moreover, a general motif-based topology discovery framework is described which exploits the poset structure of the VNet embedding relation. [ABSTRACT FROM AUTHOR]

Generalized joint hypermobility (GJH) is a frequent entity in rheumatology with higher prevalence among women. It is associated with chronic widespread pain, joint dislocations, arthralgia, fibromyalgia and early osteoarthritis. Stair climbing is an important functional task and can induce symptoms in hypermobile persons. The aim of this study was to compare ground reaction forces (GRF) and muscle activity during stair climbing in women with and without GJH. A cross-sectional study of 67 women with normal mobility and 128 hypermobile women was performed. The hypermobile women were further divided into 56 symptomatic and 47 asymptomatic. GRFs were measured by force plates embedded in a six step staircase, as well as surface electromyography (EMG) of six leg muscles. Parameters derived from GRF and EMG were compared between groups using t -test and ANOVA. For GRF no significant differences were found. EMG showed lower activity for the quadriceps during ascent and lower activity for hamstrings and quadriceps during descent in hypermobile women. For symptomatic hypermobile women these differences were even more accentuated. The differences in EMG may point towards an altered movement pattern during stair climbing, aimed at avoiding high muscle activation. However, differences were small, since stair climbing seems to be not demanding. [ABSTRACT FROM AUTHOR]

A small strain plasticity model, based on the principles of continuum mechanics, is incorporated into a phase-field model for heterogeneous microstructures in polycrystalline and multiphase material systems (Nestler et al., Phys Rev 71:1-6, ). Thereby, the displacement field is computed by solving the local momentum balance dynamically (Spatschek et al., Phys Rev 75:1-14, ) using the finite difference method on a staggered grid. The elastic contribution is expressed as the linear approximation according to the Cauchy stress tensor. In order to calculate the plastic strain, the Prandtl-Reuss model is implemented consisting of an associated flow rule in combination with the von Mises yield criterion and a linear isotropic hardening approximation. Simulations are performed illustrating the evolution of the stress and plastic strain using a radial return mapping algorithm for single phase system and two phase microstructures. As an example for interface evolution coupling with elasto-plastic effects, we present crack propagation simulations in ductile material. [ABSTRACT FROM AUTHOR]

Cobalt oxide thin films were deposited by metal-organic chemical vapor deposition at low pressure using dicarbonyl cyclopentadienyl cobalt (CoCp(CO) 2 ) and oxygen as reactant gas. Depending on substrate temperature and oxygen partial pressure, thin films consist of metallic cobalt, cobalt (II) oxide (CoO) or cobalt (II,III) oxide (Co 3 O 4 ). The films show excellent conformality on three dimensional surface structures. Films were characterized using photoelectron spectroscopy (XPS), Raman spectroscopy and scanning electron spectroscopy. XPS analysis was performed in-situ after the deposition process, allowing insights into the decomposition process of the precursor. [ABSTRACT FROM AUTHOR]

The thermal conductivity of ten ionic liquids (ILs) based on the anions $$[\mathrm{C(CN)}_{3}]^{-}$$ (tricyanomethanide) and $$[\mathrm{B(CN)}_{4}]^{-}$$ (tetracyanoborate) carrying a homologous series of the [alkyl-MIM] $$^{+}$$ (1-alkyl-3-methylimidazolium) cations [EMIM] $$^{+}$$ (ethyl), [BMIM] $$^{+}$$ (butyl) [HMIM] $$^{+}$$ (hexyl), [OMIM] $$^{+}$$ (octyl), [DMIM] $$^{+}$$ (decyl) was measured by a steady-state guarded parallel-plate instrument in the temperature range between (283.15 and 353.15) K at atmospheric pressure with a total uncertainty of 5 % ( $$k\,=\,2$$ ). Furthermore, the refractive index required for data evaluation and the density, which is an important property in the developed prediction method for the thermal conductivity, were determined. In general, the measured thermal conductivities of the probed ILs decrease with increasing temperature and increasing alkyl-chain length of the cation. Regarding the influence of the anion, somewhat smaller values for the $$[\mathrm{B(CN)}_{4}]^{-}$$ -based ILs compared to the $$[\mathrm{C(CN)}_{3}]^{-}$$ -based ILs carrying the same cation are observed. Our previously developed simple prediction method for the thermal conductivity of ILs at 293.15 K using only information on the molar mass and the density could be improved. By the combination of this approach with the temperature dependence of the density, an extended empirical correlation additionally describing the temperature dependence of the thermal conductivity of ILs is recommended. This correlation represents all experimental thermal-conductivity data in the literature with a standard deviation of less than 7 %. [ABSTRACT FROM AUTHOR]

Background: Joint hypermobility is known to be associated with joint and muscle pain, joint instability and osteoarthritis. Previous work suggested that those individuals present an altered neuromuscular behavior during activities such as level walking. Therefore, the aim of this study was to explore the differences in ground reaction forces, temporal parameters and muscle activation patterns during gait between normomobile and hypermobile women, including symptomatic and asymptomatic hypermobile individuals. Methods: A total of 195 women were included in this cross-sectional study, including 67 normomobile (mean 24.8 [SD 5.4] years) and 128 hypermobile (mean 25.8 [SD 5.4] years), of which 56 were further classified as symptomatic and 47 as asymptomatic. The remaining 25 subjects could not be further classified. Ground reaction forces and muscle activation from six leg muscles were measured while the subjects walked at a self-selected speed on an instrumented walkway. Temporal parameters were derived from ground reaction forces and a foot accelerometer. The normomobile and hypermobile groups were compared using independent samples t-tests, whereas the normomobile, symptomatic and asymptomatic hypermobile groups were compared using one-way ANOVAs with Tukey post-hoc tests (significance level=0.05). Findings: Swing phase duration was higher among hypermobile (P =0.005) and symptomatic hypermobile (P =0.018) compared to normomobile women. The vastus medialis (P =0.049) and lateralis (P =0.030) and medial gastrocnemius (P =0.011) muscles showed higher mean activation levels during stance in the hypermobile compared to the normomobile group. Interpretation: Hypermobile women might alter their gait pattern in order to stabilize their knee joint. [ABSTRACT FROM AUTHOR]

Background: Joint hypermobility is known to be associated with joint and muscle pain, joint instability and osteoarthritis. Previous work suggested that those individuals present an altered neuromuscular behavior during activities such as level walking. Therefore, the aim of this study was to explore the differences in ground reaction forces, temporal parameters and muscle activation patterns during gait between normomobile and hypermobile women, including symptomatic and asymptomatic hypermobile individuals. Methods: A total of 195 women were included in this cross-sectional study, including 67 normomobile (mean 24.8 [SD 5.4] years) and 128 hypermobile (mean 25.8 [SD 5.4] years), of which 56 were further classified as symptomatic and 47 as asymptomatic. The remaining 25 subjects could not be further classified. Ground reaction forces and muscle activation from six leg muscles were measured while the subjects walked at a self-selected speed on an instrumented walkway. Temporal parameters were derived from ground reaction forces and a foot accelerometer. The normomobile and hypermobile groups were compared using independent samples t-tests, whereas the normomobile, symptomatic and asymptomatic hypermobile groups were compared using one-way ANOVAs with Tukey post-hoc tests (significance level=0.05). Findings: Swing phase duration was higher among hypermobile (P =0.005) and symptomatic hypermobile (P =0.018) compared to normomobile women. The vastus medialis (P =0.049) and lateralis (P =0.030) and medial gastrocnemius (P =0.011) muscles showed higher mean activation levels during stance in the hypermobile compared to the normomobile group. Interpretation: Hypermobile women might alter their gait pattern in order to stabilize their knee joint. [Copyright &y& Elsevier]

Traceroute measurements are one of the main instruments to shed light onto the structure and properties of today's complex networks such as the Internet. This article studies the feasibility and infeasibility of inferring the network topology given traceroute data from a worst-case perspective, i.e., without any probabilistic assumptions on, e.g., the nodes' degree distribution. We attend to a scenario where some of the routers are anonymous, and propose two fundamental axioms that model two basic assumptions on the traceroute data: (1) each trace corresponds to a real path in the network, and (2) the routing paths are at most a factor $$1/\alpha $$ off the shortest paths, for some parameter $$\alpha \in (0,1]$$. In contrast to existing literature that focuses on the cardinality of the set of (often only minimal) inferrable topologies, we argue that a large number of possible topologies alone is often unproblematic, as long as the networks have a similar structure. We hence seek to characterize the set of topologies inferred with our axioms. We introduce the notion of star graphs whose colorings capture the differences among inferred topologies; it also allows us to construct inferred topologies explicitly. We find that in general, inferrable topologies can differ significantly in many important aspects, such as the nodes' distances or the number of triangles. These negative results are complemented by a discussion of a scenario where the trace set is best possible, i.e., 'complete'. It turns out that while some properties such as the node degrees are still hard to measure, a complete trace set can help to determine global properties such as the connectivity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Degradation of environmental toxins, a protein, and bioparticles were studied. [•] A commercial air purifier based on a cold plasma was used. [•] Passage through the device reduced the concentration of the compounds/particles. [•] Deposition inside the plasma air purifier was the main removal process. [ABSTRACT FROM AUTHOR]

Abstract: Pathologies that lead to biomechanical restrictions in human gait interfere with the tightly regulated muscle activation patterns that control the external moments. In order to maintain proper function, secondary mechanisms are required. The aims of this systematic review were (1) to identify secondary mechanisms in pathologic gait that have been described throughout the scientific literature by means of instrumented gait analysis, (2) to distinguish between active compensatory mechanisms and passive physical effects and (3) to identify common compensatory mechanisms that appear to be independent from the underlying disease. A comprehensive literature search revealed 4080 citations for review, whereof 148 studies entered the full-text review. Thirty-six studies were included and the quality of these studies was assessed by two independent reviewers (kappa=0.83). The quality of the included studies showed large variation and several methodological issues were identified. Five studies were further identified describing only passive physical effects, leaving a total of 31 studies reporting on compensations. The qualitative analysis revealed common compensations that appeared to be independent from the underlying pathology. In clinical practice, distinguishing primary from secondary gait deviations can be considered highly important since unnecessary treatment may be avoided. However, given the introduction of general principles of compensatory mechanisms and the fact that certain presumed “compensations” were identified as simple passive physical effects, secondary gait deviations have to be further investigated. Computer simulation studies are valuable, especially in respect of the distinction between compensations and physical effects. Furthermore, the need for a uniform terminology was highlighted. [Copyright &y& Elsevier]

We present a tectonic map of the Tauern Window and surrounding units (Eastern Alps, Austria), combined with a series of crustal-scale cross-sections parallel and perpendicular to the Alpine orogen. This compilation, largely based on literature data and completed by own investigations, reveals that the present-day structure of the Tauern Window is primarily characterized by a crustal-scale duplex, the Venediger Duplex (Venediger Nappe system), formed during the Oligocene, and overprinted by doming and lateral extrusion during the Miocene. This severe Miocene overprint was most probably triggered by the indentation of the Southalpine Units east of the Giudicarie Belt, initiating at 23-21 Ma and linked to a lithosphere-scale reorganization of the geometry of mantle slabs. A kinematic reconstruction shows that accretion of European lithosphere and oceanic domains to the Adriatic (Austroalpine) upper plate, accompanied by high-pressure overprint of some of the units of the Tauern Window, has a long history, starting in Turonian time (around 90 Ma) and culminating in Lutetian to Bartonian time (45-37 Ma). [ABSTRACT FROM AUTHOR]

New zircon and apatite fission-track (FT) data, including apatite thermal modelling, are combined with an extensive literature survey and reconnaissance-type structural fieldwork in the Eastern Apuseni Mountains. This leads to a better understanding of the complex structural and thermal history of a key area at the boundary between two megatectonic units in the Balkan peninsula, namely the Tisza and Dacia Mega-Units. Following Late Jurassic obduction of the Transylvanian ophiolites onto a part of the Dacia Mega-Unit, that is, the Biharia nappe system, both units were buried to a minimum of 8 km during late Early Cretaceous times when these units were underthrust below the Tisza Mega-Unit consisting of the present-day Codru and Bihor nappe systems. Tisza formed the upper plate during Early Cretaceous ('Austrian') east-facing orogeny. Turonian to Campanian zircon FT cooling ages (95-71 Ma) from the Bihor and Codru nappe systems and the Biharia and Baia de Arieş nappes (at present the structurally lowest part of the Dacia Mega-Unit) record exhumation that immediately followed a second Cretaceous-age (i.e. Turonian) orogenic event. Thrusting during this overprinting event was NW-facing and led to the overall geometry of the present-day nappe stack in the Apuseni Mountains. Zircon FT ages, combined with thermal modelling of the apatite FT data, show relatively rapid post-tectonic cooling induced by a third shortening pulse during the latest Cretaceous ('Laramian' phase), followed by slower cooling across the 120°-60 °C temperature interval during latest Cretaceous to earliest Paleogene times (75-60 Ma). Cenozoic-age slow cooling (60-40 Ma) was probably related to erosional denudation postdating 'Laramian' large-scale updoming. [ABSTRACT FROM AUTHOR]

We describe a hybrid vacuum system in which a single ion or a well-defined small number of trapped ions (in our case Ba+ or Rb+) can be immersed into a cloud of ultracold neutral atoms (in our case Rb). This apparatus allows for the study of collisions and interactions between atoms and ions in the ultracold regime. Our setup is a combination of a Bose-Einstein condensation apparatus and a linear Paul trap. The main design feature of the apparatus is to first separate the production locations for the ion and the ultracold atoms and then to bring the two species together. This scheme has advantages in terms of stability and available access to the region where the atom-ion collision experiments are carried out. The ion and the atoms are brought together using a moving one-dimensional optical lattice transport which vertically lifts the atomic sample over a distance of 30 cm from its production chamber into the center of the Paul trap in another chamber. We present techniques to detect and control the relative position between the ion and the atom cloud. [ABSTRACT FROM AUTHOR]

Plasma air purifying systems present an interesting alternative to filters for purifying air. In this study, molecular processes in a commercially available ac driven plasma air purifier were studied in detail. This air purifier is supposed to reduce all air contaminants to small nontoxic molecules (e.g., H2O and CO2). However, degradation mechanisms are not yet fully understood. In this study, we investigated the exhaust of the plasma air purifier to determine which degradation products are formed. An interface was designed and constructed to allow the direct coupling of the plasma air purifier’s exhaust to a mass spectrometer. The compounds studied, primary and secondary amines, were introduced at a concentration of 1 ppmV. Contrary to our expectations, polymerization instead of degradation was observed. The higher the ac voltage applied (max. 9.0 kV) to the plasma air purifier, the higher the mass of the oligomer distribution. Side chain oxidation products as well as oligomers could be observed for all compounds tested. Starting with amines of low mass (m/z < 200), compounds of molecular masses above 1000 Da were observed in the plasma air purifier. Detailed analysis of the observed mass spectra as well as experiments with deuterated dibutylamine helped to unravel the mechanism taking place in the plasma air purifier. Nitrate anions generated in the plasma air purifier (presumably from N2) are proposed to form ionic clusters with protonated amines. [ABSTRACT FROM AUTHOR]

Background: Heterozygous mutations in the glucocerebrosidase gene lead to an increased risk for and to more severe alpha-synuclein-associated pathology in Parkinson's disease. As both glucocerebrosidase and alpha-synuclein interact with fatty acids, we hypothesized that cerebrospinal fluid fatty acid levels are altered in these Parkinson's disease patients. Methods: Cerebrospinal fluid levels of 13 fatty acids in 8 Parkinson's disease patients with a heterozygous glucocerebrosidase mutation were compared with those of 41 idiopathic Parkinson's disease patients and 30 controls using gas chromatography. Results: Parkinson's disease patients with a heterozygous glucocerebrosidase mutation had lower levels of palmitoleic ( P ≤ .007), oleic ( P ≤ .016), linoleic ( P ≤ .005), arachidonic ( P ≤ .003), eicosapentaenoic ( P ≤ .003) and decosahexaenoic ( P ≤ .03) acids and lower levels of total fatty acids ( P < .005) compared with both idiopathic Parkinson's disease patients and control subjects. Conclusions: These results suggest that abnormalities of fatty acid metabolism are specifically involved in the pathogenesis of Parkinson's disease associated with a heterozygous glucocerebrosidase mutation. © 2011 Movement Disorder Society [ABSTRACT FROM AUTHOR]

This cross-sectional study evaluated the intrasession reliability and concurrent validity of trunk accelerometry (with force plate measurements) for vertical ground reaction force and external mechanical power recorded during a standardized heel-rise (HR) test in 54 elderly subjects (mean +/- standard deviation age 81.2 +/- 6.4 yr). Peak force as well as peak and average power revealed intraclass correlation coefficients of >0.75 and low standard errors of measurement for both the force plate- and the accelerometer-based curves. Correlation coefficients for these variables ranged from 0.95 to 0.98. The accelerometry-derived variables indicated significantly lower absolute values. Trunk accelerometry can be used as a reliable and valid tool for the quantification of the HR test in the elderly population. However, due to several limitations in the protocol, the use of this tool can currently only be recommended in a test-retest manner. Therefore, more research is needed to fully validate this tool for clinical use. [ABSTRACT FROM AUTHOR]

Current peer-to-peer (P2P) systems often suffer from a large fraction of freeriders not contributing any resources to the network. Various mechanisms have been designed to overcome this problem. However, the selfish behavior of peers has aspects which go beyond resource sharing. This paper studies the effects on the topology of a P2P network if peers selfishly select the peers to connect to. In our model, a peer exploits locality properties in order to minimize the latency (or response times) of its lookup operations. At the same time, the peer aims at not having to maintain links to too many other peers in the system. By giving tight bounds on the price of anarchy, we show that the resulting topologies can be much worse than if peers collaborated. Moreover, the network may never stabilize, even in the absence of churn. Finally, we establish the complexity of Nash equilibria in our game theoretic model of P2P networks. Specifically, we prove that it is NP-hard to decide whether our game has a Nash equilibrium and can stabilize. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of the study was to determine the reliability of vertical ground reaction force (VGRF) parameters during stair ascent and descent in the elderly. Forty-two elderly subjects (80.1 SD 6.4 years) were asked to perform three stair ascents and descents at their self-selected normal speed. VGRF were measured during two consecutive steps on an instrumented staircase. Force–time curves where then parameterized into force, force-time and time variables, according to a previously suggested protocol. In addition, force and force-time variables were normalized to body weight. Intraclass correlation coefficients (ICC) type (2, 1) and coefficients of variation (CV) were calculated. Force variables showed moderate to good reliability for the normalized values with ICCs ranging from 0.537 to 0.836 and CVs between 2.52% and 6.51%. Variability of Fmax1 and Fmin appeared to be higher in stair descent with CVs of >5.20% as compared to stair ascent (<3.75%). Time variables showed good reliability in stair ascent but were clearly lower in stair descent (ICCs between 0.108 and 0.684 and CVs between 10.70% and 14.45%). Significant differences were found for the ICCs between the absolute and normalized values as well as for the ICCs of the time dependent and CVs of all variables between stair ascent and descent.It has been concluded that VGRF parameters can be used as a reliable measurement tool for the quantification of stair climbing in the elderly. The present data can be further used as reference values in future investigations. [Copyright &y& Elsevier]

This article reports on the results of our measurement study of the Kad network. Although several fully decentralized peer-to-peer systems have been proposed in the literature, most existing systems still employ a centralized architecture. The Kad network is a notable exception. Since the demise of the Overnet network, the Kad network has become the most popular peer-to-peer system based on a distributed hash table. It is likely that its user base will continue to grow in numbers over the next few years due to the system's scalability and reliability. The contribution of the article is twofold. First, we compare the two networks accessed by eMule: the centralized paradigmof the eDonkey network and the structured, distributed approach pursued by the Kad network. We re-engineer the eDonkey server software and integrate two modified servers into the eDonkey network in order to monitor traffic. Additionally, we implement a Kad client exploiting a design weakness to spy on the traffic at arbitrary locations in the ID space. The collected data provides insights into the spacial and temporal distributions of the peers' activity. Moreover, it allows us to study the searched content. The article also discusses problems related to the collection of such data sets and investigates techniques to verify the representativeness of the measured data. Second, this article shows that today's Kad network can be attacked in several ways. Our simple attacks could be used either to hamper the correct functioning of the network itself, to censor content, or to harm other entities in the Internet not participating in the Kad network, such as ordinary web servers. While there are heuristics to improve the robustness of Kad, we believe that the attacks cannot be thwarted easily in a fully decentralized peer-to-peer system, i.e., without some kind of a centralized certification and verification authority. This result may be relevant in the context of the current debate on the design of a clean-slate network architecture for the Internet which is based on concepts known from the peer-to-peer paradigm. [ABSTRACT FROM AUTHOR]

Abstract: Electrosonic spray ionization (ESSI) has been studied as an interface between high-performance liquid chromatography (HPLC) and mass spectrometry (MS), using sample flow rates up to 3.0mlmin−1. This ionization interface was compared with pneumatically assisted electrospray ionization (ESI) using mass spectrometry for detection. For experiments that did not involve direct comparison of different flow rates, the ESI experiments were performed using post column splitting to work at optimal conditions. ESSI allows the interfacing of conventional or high-resolution liquid chromatography (LC) methods to mass spectrometry without post column splitting. High sample flow rates could be handled without a significant loss of signal intensity using a nebulization gas flow rate of 5.5Lmin−1. Since ESI needs to be operated with lower sample flow rates, it is limited to micro/nano LC systems, or post column splitting must be used. In particular, nano LC systems have to be treated with great care and require constant maintenance. When using post-column splitting, the increased diffusion can become a problem especially when using systems with very small void volumes. In all experiments ESSI showed better signal intensities than a commercially available, pneumatically assisted ESI source. ESSI does not require heating of the nebulizer gas, which should help to preserve the original structure of thermally unstable molecules. Therefore, ESSI is presented as an alternative to the commercially available heated ESI sources of AB SCIEX, Thermo Fischer, Agilent and Waters. The observed LC-ESSI-MS ion chromatograms are shown to be very stable even when using flow rates higher than 1.0mlmin−1, which could be very suitable for ultra high performance LC, where sample flow rates up to 2.0mLmin−1 with backpressures up to 1200bar are used. Also, a difference in the relative intensities of singly and doubly protonated peptide monomers and dimers was observed between the two ionization methods. The coefficients of determination for the calibration of instrument response for Val–Tyr–Val and Met-Enkephalin showed excellent linearity over a wide concentration range (0.1–100μM), while ESI results were only linear over a much smaller range (0.1–20μM). The observed behavior is thought to be caused by insufficient ionization efficiency of solutions above ∼20μM by ESI, exemplifying the robustness of ESSI as an interface between LC and MS. [Copyright &y& Elsevier]

Abstract: During sporting events, injured athletes often return to competition after icing because of the reduction in pain. Although some controversy exists, several studies suggest that cryotherapy causes a decrease in muscle activity, which may lead to a higher risk of injury upon return to play. The purpose of this study was to investigate the effect of a 20-min knee joint cryotherapy application on the electromyographic activity of leg muscles during a single-leg drop jump in twenty healthy subjects, randomly assigned to an experimental and a control group. After the pre-tests, a crushed-ice bag was applied to the knee joint of the experimental group subjects for 20min, while the control group subjects rested for 20min. All subjects were retested immediately after this period and retested again after another 20min of rest. Average electromyographic activity and ground contact time were calculated for the pre- and post-test sessions. Decreases in electromyographic activity of the lower extremity musculature were found in pre-activation, eccentric (braking), and concentric (push-off) phases immediately after the icing, and after 20min of rest. The results lend support to the suggestion that cryotherapy during sporting events may place the individuals in a vulnerable position. [ABSTRACT FROM AUTHOR]

Abstract: A new reconstruction of Alpine Tethys combines plate-kinematic modelling with a wealth of geological data and seismic tomography to shed light on its evolution, from sea-floor spreading through subduction to collision in the Alps. Unlike previous models, which relate the fate of Alpine Tethys solely to relative motions of Africa, Iberia and Europe during opening of the Atlantic, our reconstruction additionally invokes independent microplates whose motions are constrained primarily by the geological record. The motions of these microplates (Adria, Iberia, Alcapia, Alkapecia, and Tiszia) relative to both Africa and Europe during Late Cretaceous to Cenozoic time involved the subduction of remnant Tethyan basins during the following three stages that are characterized by contrasting plate motions and driving forces: (1) 131–84Ma intra-oceanic subduction of the Ligurian part of Alpine Tethys attached to Iberia coincided with Eo-alpine orogenesis in the Alcapia microplate, north of Africa. These events were triggered primarily by foundering of the older (170–131Ma) Neotethyan subduction slab along the NE margin of the composite African–Adriatic plate; subduction was linked by a sinistral transform system to E–W opening of the Valais part of Alpine Tethys; (2) 84–35Ma subduction of primarily the Piemont and Valais parts of Alpine Tethys which were then attached to the European plate beneath the overriding African and later Adriatic plates. NW translation of Adria with respect to Africa was accommodated primarily by slow widening of the Ionian Sea; (3) 35Ma–Recent rollback subduction of the Ligurian part of Alpine Tethys coincided with Western Alpine orogenesis and involved the formation of the Gibraltar and Calabrian arcs. Rapid subduction and arc formation were driven primarily by the pull of the gravitationally unstable, retreating Adriatic and African slabs during slow convergence of Africa and Europe. The upper European–Iberian plate stretched to accommodate this slab retreat in a very mobile fashion, while the continental core of the Adriatic microplate acted as a rigid indenter within the Alpine collisional zone. The subducted lithosphere in this reconstruction can be correlated with slab material imaged by seismic tomography beneath the Alps and Apennines, as well as beneath parts of the Pannonian Basin, the Adriatic Sea, the Ligurian Sea, and the Western Mediterranean. The predicted amount of subducted lithosphere exceeds the estimated volume of slab material residing at depth by some 10–30%, indicating that parts of slabs may be superposed within the mantle transition zone and/or that some of this subducted lithosphere became seismically transparent. [Copyright &y& Elsevier]

Until now, the analysis of fault tolerance of peer-to-peer systems usually only covers random faults of some kind. Contrary to traditional algorithmic research, faults as well as joins and leaves occurring in a worst-case manner are hardly considered. In this article, we devise techniques to build dynamic peer-to-peer systems which remain fully functional in spite of an adversary who continuously adds and removes peers. We exemplify our algorithms on hypercube and pancake topologies and present a system which maintains small peer degree and network diameter. [ABSTRACT FROM AUTHOR]