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Attosecond pulse shaping using a seeded free-electron laser

Attosecond pulses are central to the investigation of valence- and core-electron dynamics on their natural timescales1–3. The reproducible generation and characterization of attosecond waveforms has been demonstrated so far only through the process of high-order harmonic generation4–7. Several methods for shaping attosecond waveforms have been proposed, including the use of metallic filters8,9, mu

The Politics of Voter Presence

By focusing only on the composition of representative bodies, the traditional ‘politics of presence’ approach has inadvertently diminished the value of participation for representation. It overlooks that there exist ‘elite voters’ who reinforce discrimination against abstainers at the policy level and create obstacles for improving the lives of the marginalized. We offer a remedy to persisting pat

Influence of the cavity field flatness and effect of the phase reference line errorson the beam dynamics of the ESS LINAC

The particle longitudinal dynamics is affected by errors on the phase and amplitude of the electro-magnetic field in each cavity that cause emittance growth, beam degradation and losses. One of the causes of the phase error is the change of the ambience temperature in the LINAC tunnel, in the stub and in the klystron gallery that induces a phase drift of the signal travelling through the cables an

The catalytic nature of protein aggregation

The formation of amyloid fibrils from soluble peptide is a hallmark of many neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Characterization of the microscopic reaction processes that underlie these phenomena have yielded insights into the progression of such diseases and may inform rational approaches for the design of drugs to halt them. Experimental evidence suggests th

Climate and vegetation dynamics of the Northern Apennines (Italy) during the Late Pleistocene and Holocene

This study reconstructs the regional vegetation and climate dynamics between the upper Late Pleistoceneand Holocene around Pian del Lago, a coastal mountain marshland located at 831 m asl in westernLiguria (NW-Italy), based on the pollen analysis of a 13 m-long sediment core. The record provided aunique opportunity to study a poorly documented period in northern Italy and across many parts ofsouth

Duration of load behaviour of a glued shear plate dowel joint

An experimental study on the duration of load effects in a glued shear plate dowel joint was conducted. The joint design features a single large diameter dowel for load transfers between members, via external steel plates, which are bonded to the timber with a low stiffness bond line. Due to the low bond line stiffness, the timber element is subjected to a close to uniform shear stress distributio

The saturated regime of a seeded single-pass free electron laser : A theoretical investigation through the statistical mechanics of the Vlasov equation

The quasi-stationary state characterizing the saturation of a single-pass free-electron laser is governed by the Vlasov equation obtained by performing the continuum limit of the Colson-Bonifacio model. By means of a statistical treatment, this approach allows to predict analytically the saturated laser intensity as well as the final electron-beam energy distribution. In this paper we consider the

FLASH - Present status and commissioning results

The sFLASH-experiment has been built at the Free- Electron Laser in Hamburg (FLASH) to study the highgain- FEL amplification of a laser seed from a high harmonic generation (HHG) source. Ideally, the HHG seed can be amplified up to a GW-power level, improving both the shot-to-shot stability and the longitudinal coherence of the FEL-pulse. In 2010/2011 the sFLASH-components and sub-systems have bee

Dowel design of the shear plate dowel joint

The shear plate dowel joint (SPDJ) is a novel connection design for heavy timber structures. The connection uses a single large diameter dowel and glued-on steel plates to transfer loads between members. Consequently, the design of the dowel is of great influence for the global performance of the connection. This paper presents an experimental and numerical investigation of the influence of the ge

Spatial relationship between telocytes, interstitial cells of Cajal and the enteric nervous system in the human ileum and colon

Telocytes (TCs) are recently described interstitial cells, present in almost all human organs. Among many other functions, TCs regulate gastrointestinal motility together with the interstitial cells of Cajal (ICCs). TCs and ICCs have close localization in the human myenteric plexus; however, the exact spatial relationship cannot be clearly examined by previously applied double immunofluorescence/c

Detection of F8 int22h inversions using digital droplet PCR and mile-post assays

BACKGROUND: Inversions involving intron 22 (Inv22) of F8 are detected in approximately 45% of all severe hemophilia A patients. Diagnosis is complicated by the large size of the ~9.5 kb int22h repeated sequence which generates the inversions. Methods such as long-range PCR and inverse-shifting PCR are currently used diagnostically, but suffer from low PCR efficiencies and are difficult to standard

Protein crystallization benefits from the rough well surface of a 48-well polystyrene microplate

It’s not clear whether the drop well surface can induce heterogeneous nucleation to increase the probability of screening success, although a medium-throughput 48-well SBS (the Society for Biomolecular Screening, USA) polystyrene microplate has been widely used for protein crystallization screening. Here, our accumulating data suggested that this 48-well SBS microplate with rough surface is benefi

Adaptive Scatter Search to Solve the Minimum Connected Dominating Set Problem for Efficient Management of Wireless Networks

An efficient routing using a virtual backbone (VB) network is one of the most significant improvements in the wireless sensor network (WSN). One promising method for selecting this subset of network nodes is by finding the minimum connected dominating set (MCDS), where the searching space for finding a route is restricted to nodes in this MCDS. Thus, finding MCDS in a WSN provides a flexible low-c