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Significant uncertainties remain regarding the field assessment of the peak shear strength of rock joints. These uncertainties mainly originate from the lack of a verified methodology that would permit prediction of rock joints’ peak shear strength accounting for their surface area, while using information available from smaller samples. This paper investigates a methodology that uses objective observations of the 3D roughness and joint aperture from drill cores to predict the peak shear strength of large natural, unfilled rock joints in the field. The presented methodology has been tested in the laboratory on two natural, unfilled rock joint samples of granite. The joint surface area of the tested samples was of approximately 500 × 300 mm. In this study, the drill cores utilised to predict the peak shear strength of the rock joint samples are simulated based on a subdivision of their digitised surfaces obtained through high-resolution laser scanning. The peak shear strength of the tested samples based on the digitised surfaces of the simulated drill cores is predicted by applying a peak shear strength criterion that accounts for 3D roughness, matedness, and specimen size. The results of the performed analysis and laboratory experiments show that data from the simulated drill cores contain the necessary information to predict the peak shear strength of the tested rock joint samples. The main benefit of this approach is that it may enable the prediction of the peak shear strength in the field under conditions of difficult access.

National emission reduction targets under the Paris Agreement have a territorial focus, incentivizing mitigation actions domestically. Here we scrutinize the theoretical basis for adopting complementary consumption-based net-zero emission targets and assess the consequences of adopting such proposed targets for Sweden. We apply scenario analyses based on a prospective lifecycle assessment framework. The framework is a hybrid between bottom-up simulations – for passenger travel, construction and housing, and food – and top-down analyses covering remaining consumption. In this work, we show how consumption-based climate targets accentuate the need for new demand-side climate policies that contribute to reducing emissions along value chains of products and services. Combining advanced mitigation technologies with behavioral changes could achieve emission reductions from 9.8 tons of carbon dioxide equivalents per capita in 2019 to between 2.7 and 4.8 tons by 2045 for Swedish residents, depending on global decarbonization pathways.

Changes in travel behaviour are needed to tackle the climate impact associated with long-distance flights, including a switch to sustainable transport modes. In this paper, we analyse scenarios of carbon footprint reduction associated with a switch from flights to night trains for holidays in Europe for the case of Sweden, including outbound, inbound and domestic tourism. We use a prospective lifecycle assessment framework combined with results from a stated preference experiment to determine the impact of future mode shift behaviours. Our results indicate that a mode shift could be triggered by progressive night train policies resulting in (i) fewer transfers and (ii) price levels similar to those of flights. The shifts from flights to night trains could result in 7–9% lower cumulative carbon footprint in relation to a baseline travel demand scenario for the period 2025-2050, depending on the decarbonization pathway. Decarbonization of long-distance travel in line with the Paris Agreement would likely require a combination of many different types of measures including a shift to low-carbon fuels.

Possible strategies to mitigate the climate impact of tourism transport include encouraging tourism to closer destinations and supporting more sustainable modes of transport, including trains. Today international trips by railways only have a small market share but night trains are considered an important part of a future green Europe. However, little is known about travelers’ preferences for night trains for long-distance travel in Europe. The results of an integrated choice and latent variable model (ICLV) applied to stated preference (SP) data collected from 1,691 residents of Sweden show that, depending on place of origin in Sweden, in response to a set of innovations, including reduced travel time emanating from ongoing infrastructure investments, and the introduction of new, more comfortable trains, the share of plane users willing to switch to night trains to Central Europe could reach 20-30% and to Southern Europe, 6-10%.

The aim of this study is to explore a work-life policy granting employees extended rights to part-time work, from an employer perspective. Employees working part-time in the City of Gothenburg, Sweden, were surveyed and line managers interviewed to analyze the part-time arrangement. Line managers perceive challenges linked to taking on new tasks, training and development, and communication. Five manager strategies to handle employee-driven part-time were identified: Intensification of work and overtime for part-time employees and colleagues, job task management, reduced flexibility, and recruitment and retention. The use of strategies is related to the level and frequency of part-time work arrangements.

A 1.5 Å resolution crystal structure of bovine trypsin at room temperature has been determined using 150 fs X-ray diffraction snapshots at the FemtoMAX beamline of the MAX IV facility., Protein dynamics contribute to protein function on different time scales. Ultrafast X-ray diffraction snapshots can visualize the location and amplitude of atom displacements after perturbation. Since amplitudes of ultrafast motions are small, high-quality X-ray diffraction data is necessary for detection. Diffraction from bovine trypsin crystals using single femtosecond X-ray pulses was recorded at FemtoMAX, which is a versatile beamline of the MAX IV synchrotron. The time-over-threshold detection made it possible that single photons are distinguishable even under short-pulse low-repetition-rate conditions. The diffraction data quality from FemtoMAX beamline enables atomic resolution investigation of protein structures. This evaluation is based on the shape of the Wilson plot, cumulative intensity distribution compared with theoretical distribution, I/σ, R merge/R meas and CC1/2 statistics versus resolution. The FemtoMAX beamline provides an interesting alternative to X-ray free-electron lasers when studying reversible processes in protein crystals.

Air travel has received increasing attention in the climate debate in recent years. Current climate policy in this sector remains weak in comparison to, for example, the road transport sector. In t...

The impact of shear displacement under different mechanical boundary conditions on fluid flow and advective transport in a single fracture at the laboratory scale is demonstrated in the present study. The shear-induced changes of fracture aperture structures are determined by using the measured normal displacements and digitalized fracture surfaces from laboratory shear tests. Five shear tests on concrete replicas of the same fracture under different mechanical boundary conditions, including constant normal loading (CNL) and constant normal stiffness (CNS), are conducted to analyse the influence of mechanical boundary conditions on the shear-flow-transport processes. Fluid flow in the fracture with different shear displacements are simulated by solving the Reynolds equation. The Lagrangian particle tracking method is applied to model the advective transport in the fracture after shearing. The results generally show that the shear displacements and the normal loading conditions can significantly affect flow patterns and advective travel time distributions in the fracture. For mated fractures, the flow and transport will be enhanced by the increasing shear displacement because of shear dilation. For cases with the same shear displacement, the median advective travel time increases with the increasing boundary normal stiffness. The median advective travel time under the CNS boundary condition is generally longer than that under the CNL boundary condition. The results from this study can help to improve our understanding of stress-dependent solute transport processes in natural rock fractures.

Aviation constitutes about 2.5% of all energy-related CO2 emissions and in addition there are non-CO2 effects. In 2016, the ICAO decided to implement a Carbon Offsetting and Reduction Scheme for In...

In many industrialised countries, the climate impact from long-distance travel is greater than that from short-distance travel. In this paper, we present five scenarios for long-distance travel in 2060, which are consistent with a 67% probability of limiting global warming to 1.8 degrees. The scenarios concern travel by the Swedish population, but per capita travel volume and fuel use could be generalised globally. A key result is that all scenarios require reductions in Swedish per capita air travel in the range of 38–59% compared to 2017. The direct effect on air travel of implementing a high-speed rail network in Sweden and Northern Europe was found to be modest. A higher emission reduction could be achieved if mixed mode trips comprising rail and air legs were more widely adopted. Finally, the pros and cons of future aviation fuels are discussed, the main candidates being biofuel, electrofuel, and liquid hydrogen.

Emissions of greenhouse gases from tourism transport are rising globally, with air transport accounting for the largest share. Although travel is not likely to decrease drastically, people could travel differently, and still have similar experiences. This study aims to map the emissions from air travel and analyse the theoretical potential for emissions reduction by changing transport mode and destinations, and the readiness potential for emissions reduction based on tourists’ stated readiness to change their travel behaviour. The theoretical potential was assessed by analysing alternative trips to closer destinations and using transport modes with lower emissions or through virtual meetings. The readiness potential was assessed by a survey designed to capture people’s stated readiness to change their behaviour. The results show a theoretical potential for an emissions reduction of 67%, while the readiness potential is 26%. About half of the readiness potential for reductions is from changing destination, while only a small share is from changing transport mode. This shows that, when accounting for people’s readiness to change behaviour, destination choice has a greater potential to reduce emissions compared to transport mode choice. This finding has implications for policy makers in designing policy measures to reduce emissions.

International audience; This study shows that initial atomic velocities as given by thermodynamics play an important role in the dynamics of phase transitions. We tracked the atomic motion during nonthermal laser-induced melting of InSb at different initial temperatures. The ultrafast atomic motion following bond breaking can in general be governed by two mechanisms: the random velocity of each atom at the time of bond breaking (inertial model), and the forces acting on the atoms after bond breaking. The melting dynamics was found to follow the inertial model over a wide temperature range.

Applying accurate normal load to a specimen in direct shear tests under constant normal stiffness (CNS) is of importance for the quality of the resulting data, which in turn influences the conclusions. However, deficiencies in the test system give rise to a normal stiffness, here designated as system normal stiffness, which results in deviations between the intended and actual applied normal loads. Aiming to reduce these deviations, this paper presents the effective normal stiffness approach applicable to closed-loop control systems. Validation through direct shear tests indicates a clear influence of the system normal stiffness on the applied normal load (13% for the test system used in this work). The ability of the approach to compensate for this influence is confirmed herein. Moreover, it is demonstrated that the differences between the measured and the nominal normal displacements are established by the normal load increment divided by the system normal stiffness. This further demonstrates the existence of the system normal stiffness. To employ the effective normal stiffness approach, the intended normal stiffness (user defined) and the system normal stiffness must be known. The latter is determined from a calibration curve based on normal loading tests using a stiff test dummy. Finally, a procedure is presented to estimate errors originating from the application of an approximate representation of the system normal stiffness. The approach is shown to effectively reduce the deviations between intended normal loads and the actual applied normal loads. Funding details: BeFo 391; Funding details: Svensk Kärnbränslehantering, SKB; Funding details: Nuclear Waste Management Organization, NWMO; Funding text 1: Open access funding provided by RISE Research Institutes of Sweden. The authors would like to acknowledge the research funding granted by BeFo Rock Engineering Research Foundation (grant proposal BeFo 391) and SKB, Swedish Nuclear Fuel and Waste Management Co, Solna, Sweden. The authors would also like to thank Adjunct Professor Diego Mas Ivars at SKB, Swedish Nuclear Fuel and Waste Management Co; Associate Professor Fredrik Johansson at KTH Royal Institute of Technology; and Adjunct Professor Erland Johnson at RISE Research Institutes of Sweden AB for their valuable contribution to this work.

This article aims to contribute to the understanding of motives for part-time work and discuss the role of preferences and constraints by studying combinations of motives for part-time work in a case where the scope for preferences is great. The data was derived from a survey of full-time employees in a Swedish municipality who have opted to work part-time with lower salary. Eight groups of part-time workers with different combinations of motives were identified using cluster analysis. Although formally all of these employees were voluntarily working part-time, to a greater or lesser extent the preference for part-time can be understood as an accommodation to constraints for all of the eight clusters. Even though the motives were complex, for many, part-time work was a strategy to cope with a high workload in relation to their own health and capacity.

Global civil aviation accounts for 4–5% of total greenhouse gas emissions and these emissions are increasing. In the absence of sufficiently effective global climate instruments, national instruments might be considered as a complement, in which case some way of allocating emissions from international air travel between countries is needed. The purpose of this paper is to develop an accounting method that reflects one country's greenhouse gas emissions from international air travel, and to apply this methodology to Sweden. The new methodology consists of three parts: the number of international air trips made by the country's residents; the average distance of these trips; and the greenhouse gas emissions per passenger km. For Sweden, data for 1990 to 2014 show an increase in the number of trips by Sweden's population of 3.6% per year, resulting in, on average, one international journey (round trip 5800 km) per capita in 2014. The average distance to the final destination has increased only marginally due to simultaneous growth in both long and short trips. However, global average greenhouse gas emissions per passenger km have decreased by 1.9% per year between 1990 and 2014. Because the increase in the number of their trips has outweighed the decrease in emissions per km, the total emissions from Swedish residents' international air travel have increased by 61% between 1990 and 2014. The total emissions from Swedish residents' air travel, including both CO2 and non-CO2-effects, were 11 Mt CO2 equivalents in 2014, which is the same level as the emissions from Swedish car traffic. This type of reliable data is important when designing policies and for getting public support for new policies.

Global greenhouse gas emissions from air travel (GHG-A) are on the rise, and projections point towards a rapid growth in the coming decades. This study aims to examine how local government (cities), addresses GHG-A in their Sustainable Energy Action Plans (SEAP). To fulfil this aim, over 200 SEAPs were analysed focusing on three issues: (1) Treatment of GHG-A in local emissions inventories; (2) Policy initiatives within this domain; and (3) The cities’ perceptions of the conflicts of interests. Results showed that more than half of the cities acknowledge the challenge of GHG-A, around one third include GHG-A in their emissions inventories, and more than one quarter have initiated policy interventions. To categorise these interventions, we have added a mode ‘governing by agenda setting’ to an existing analytical framework, ‘Modes of governing’. With their authority limited to the local setting, this mode of governing is a common channel for cities to push changes at higher levels.

We have studied strain wave generation in graphite induced by an intense ultrashort laser pulse. The study was performed in the intensity regime above the ablation threshold of graphite. The aim was to maximize the strain and, thus, also the internal pressure (stress). Laser pulses with a 1 ps temporal duration melt the surface of graphite resulting in a molten material which initially exists at the solid density. As the molten material expands, a compressive strain wave starts propagating into the crystal below the molten layer. The strain pulse was studied with time-resolved X-ray diffraction. At a temporal delay of 100 ps after laser excitation, we observed >10% compressive strain, which corresponds to a pressure of 7.2 GPa. This strain could be reproduced by hydrodynamic simulations, which also provided a temperature map as a function of time and depth.

6 pags., 5 figs., In phase-change memory devices, a material is cycled between glassy and crystalline states. The highly temperature-dependent kinetics of its crystallization process enables application in memory technology, but the transition has not been resolved on an atomic scale. Using femtosecond x-ray diffraction and ab initio computer simulations, we determined the time-dependent pair-correlation function of phase-change materials throughout the melt-quenching and crystallization process. We found a liquid–liquid phase transition in the phase-change materials AgInSbTe and GeSb at 660 and 610 kelvin, respectively. The transition is predominantly caused by the onset of Peierls distortions, the amplitude of which correlates with an increase of the apparent activation energy of diffusivity. This reveals a relationship between atomic structure and kinetics, enabling a systematic optimization of the memory-switching kinetics., F.Q., A.K., M.N., and K.S.T. gratefully acknowledge financial support from the German Research Council through the Collaborative Research Center SFB 1242 project 278162697 (“Non-Equilibrium Dynamics of Condensed Matter in the Time Domain”), project C01 (“Structural Dynamics in Impulsively Excited Nanostructures”), and individual grant So408/9-1, as well as the European Union (7th Framework Programme, grant no. 280555 GO FAST). M.J.S., R.M., and M.W. acknowledge financial support from the German Research Council through the Collaborative Research Center SFB 917 (“Nanoswitches”) and individual grant Ma-5339/2-1. M.J.S., I.R., and R.M. also acknowledge the computational resources granted by JARA-HPC from RWTH Aachen University under project nos. JARA0150 and JARA0183. M.T., A.M.L., and D.A.R. were supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, through the Division of Materials Sciences and Engineering under contract no. DE-AC02-76SF00515. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. J.L. acknowledges support from the Swedish Research Council. J.S. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities through research grant UDiSON (TEC2017-82464-R). P.Z. gratefully acknowledges funding by the Humboldt Foundation

In this reply to S. Durbin's comment on our original paper "Ultrafast terahertz-field-driven ionic response in ferroelectric BaTiO3," we concur that his final equations 8 and 9 more accurately describe the change in diffracted intensity as a function of Ti displacement. We also provide an alternative derivation based on an ensemble average over unit cells. The conclusions of the paper are unaffected by this correction.

The FemtoMAX beamline facilitates studies of the structural dynamics of materials on the femtosecond timescale. The first commissioning results are presented., The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100 fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.

In Sweden, both parents have a legal right to reduce their working hours to 30 hours per week. Quantitative analysis of 20,000 Swedish parents with children aged between 2 and 7, however, shows mothers to be 14 times more likely to work part time than fathers. Gender imbalance in parents’ part-time employment is thus even more pronounced than in their parental leave take-up, at least in Sweden. An analysis of 14 in-depth interviews with Swedish fathers who have chosen parental part-time work reveals that part-time work represents for them a way to reconcile their separate identities as professionals and as involved fathers. Nevertheless, this study revealed that certain difficulties of a more structural nature complicated this solution for these men; these issues included, in the first place, a strong full-time norm prevailing in male-dominated workplaces, and traditional ideals of masculinity centred on men’s breadwinning role. Furthermore, ideals of gender equality and involved fatherhood also showed themselves as having an impact, enabling new masculine positions for part-time working fathers to emerge.

This paper addresses the effect of working hours on energy use and greenhouse gas emissions from private consumption. Time use and consumption patterns of Swedish households are analysed to estimate the effects of changing income and availability of leisure time. The results indicate that a decrease in working time by 1% may reduce energy use and greenhouse gas emissions by about 0.7% and 0.8%, respectively. These results are mainly because of the effects of lower income and lower consumption. The partly offsetting effect of households having more time available for leisure activities is less than a tenth of the income effect. In a sketched scenario we also elaborate on the long-term impacts of a work time reduction. A gradual reduction towards a 30-hour working week in 2040 would result in a significantly slower growth of energy demand, which would also make it easier to reach climate targets.

Background: Levodopa-carbidopa intestinal gel (LCIG; Duodopa r) is used for continuous infusion in advanced Parkinsons disease. To achieve optimal effect, the LCIG dose is individually titrated, traditionally conducted during hospitalization in Sweden. However, dose adjustment depends on surrounding conditions, physical activity, and emotional stress, which is why titration at home could be beneficial. Telemedicine (TM) using a video communication system offers alternative titration procedures, allowing LCIG initiation at home. Objective: Study objectives were to show the feasibility of TM for LCIG home titration, evaluate resource use, and assess patient, neurologist, and nurse satisfaction. Methods: Four clinics enrolled 15 patients to observe efficiency and feasibility of TM-based monitoring. Results: Patient median (range) age was 67 (52-73) years and time since diagnosis was 10 (7-23) years. Median time between LCIG initiation and end of TM-assisted titration was 2.8 (2.0-13.8) days. Median time required for home titration by neurologists, nurses, and patients was (hours: minutes) 1 : 14 (0 : 29-1 : 52), 5 : 49 (2 : 46-10 : 3), and 8 : 53 (4 : 11-14 : 11), respectively. Neurologists and nurses considered this to be less time than required for hospital titration. TM allowed patients 92% free time from start to end of titration. Technical problems associated with TM contacts were rare, mostly related to digital link, and quickly resolved. Patients, neurologists, and nurses were satisfied using TM. No serious adverse events were reported; there was one device complaint (tube occlusion). Conclusions: In this study, TM-assisted LCIG titration at home was resource-efficient, technically feasible, well-accepted and was deemed satisfactory by patients, neurologists, and nurses. Funding Agencies|AbbVie AB

International audience; We have studied an X-ray switch based on a gold coated indium antimonide crystal using time-resolved X-ray diffraction and demonstrated that the switch could reduce the pulse duration of a 100 ps X-ray pulse down to 20 ps with a peak reflectivity of 8%. We have used a dynamical diffraction code to predict the performance of the switch, which was then confirmed experimentally. The experiment was carried out at the FemtoMAX beamline at the short-pulse facility of the MAX IV laboratory. The performance and limitation of the switch are discussed in terms of acoustic transport properties between the two materials and the electron transport properties of gold.

Consumption-accounted greenhouse gas (GHG) emissions (GHGEs) vary considerably between households. Research originating from different traditions, including consumption research, urban planning, and environmental psychology, have studied different types of explanatory variables and provided different insights into this matter. This study integrates explanatory variables from different fields of research in the same empirical material, including socioeconomic variables (income, household size, sex, and age), motivational variables (proenvironmental attitudes and social norms), and physical variables (dwelling types and geographical distances). A survey was distributed to 2,500 Swedish households with a response rate of 40%. GHGEs were estimated for transport, residential energy, food, and other consumption, using data from both the survey and registers, such as odometer readings of cars and electricity consumption from utility providers. The results point toward the importance of explanatory variables that have to do with circumstances rather than motivations for proenvironmental behaviors. Net income was found to be the most important variable to explain GHGEs, followed by the physical variables, dwelling type, and the geographical distance index. The results also indicate that social norms around GHG-intensive activities, for example, transport, may have a larger impact on a subject's emission level than proenvironmental attitudes.

In the contemporary discussion on society's transformation towards long-term climate targets, it is often implicitly assumed that behavioral changes, unlike technological changes, would lead to reductions in human well-being. However, this assumption has been questioned by researchers, who instead argue that people may live better lives by consuming less and reduce their environmental impact in the process. In this study we explore the relationship between greenhouse gas emissions and subjective well-being, using a sample of 1000 Swedish respondents. Our results show that there is no strong link between an individual's emissions and subjective wellbeing. We also analyze the relationship between specific emission-intensive activities and subjective well-being and find that none of the activities examined correlates with subjective well-being. Finally, we explore a hypothesis put forward in the literature, suggesting that a poor work-life balance, long commuting distances, and materialistic values may decrease individuals' subjective well-being and increase greenhouse gas emissions. Our results indicate that materialistic values do correlate with lower levels of well-being and to some extent also with higher greenhouse gas emissions.

© 2016 American Physical Society. The dynamical processes associated with electric field manipulation of the polarization in a ferroelectric remain largely unknown but fundamentally determine the speed and functionality of ferroelectric materials and devices. Here we apply subpicosecond duration, single-cycle terahertz pulses as an ultrafast electric field bias to prototypical BaTiO3 ferroelectric thin films with the atomic-scale response probed by femtosecond x-ray-scattering techniques. We show that electric fields applied perpendicular to the ferroelectric polarization drive large-amplitude displacements of the titanium atoms along the ferroelectric polarization axis, comparable to that of the built-in displacements associated with the intrinsic polarization and incoherent across unit cells. This effect is associated with a dynamic rotation of the ferroelectric polarization switching on and then off on picosecond time scales. These transient polarization modulations are followed by long-lived vibrational heating effects driven by resonant excitation of the ferroelectric soft mode, as reflected in changes in the c-axis tetragonality. The ultrafast structural characterization described here enables a direct comparison with first-principles-based molecular-dynamics simulations, with good agreement obtained.

We have employed time-resolved X-ray diffraction with picosecond temporal resolution to measure the time-dependent rocking curves of laser-irradiated asymmetrically cut single InSb crystals. Coherent acoustic phonons were excited in the crystals by irradiation with 800-nm, 100-fs laser pulses at irradiances between 0.25 and 12 mJ/cm2. The induced time-dependent strain profiles (corresponding to the coherent phonons) were monitored by diffracting collimated, monochromatic pulses of X-rays from the irradiated crystals. Recording of the diffracted radiation with a fast low-jitter X-ray streak camera resulted in an overall temporal resolution of better than 2 ps. The strain associated with the coherent phonons modifies the rocking curve of the crystal in a time-dependent manner, and the rocking curve is recorded by keeping the angle of incidence of the X-rays upon the crystal fixed, but varying the energy of the incident X-rays around a central energy of 8.453 keV (corresponding to the peak of the rocking curve of the unperturbed crystal). The observed time-dependent diffraction from the irradiated crystals is in reasonable agreement with simulations over a wide range of energies from the unperturbed rocking-curve peak.

We have performed experiments where DKDP has been irradiated by short (100 fs), laser pulses. Subsequently X-ray pulses with a duration of 100 ps were used as a probe. Time-resolved X-ray diffraction enables monitoring of the transitions between the paraelectric and ferroelectric phases. By recording the intensity of a peak only present in the paraelectric phase, we observe indications of a phase-transition following laser-irradiation of DKDP in the ferroelectric phase. We have estimated the laser heating effect, by measuring the strain (peak shifts) in the diffraction patterns. Furthermore, the orientation of the ferroelectric domains has been observed. In spite of the fact that the temperature did not rise above the Curie temperature, following interaction with this radiation, the polarization of ferroelectric domains was modified. This indicates a mechanism where short pulses impulsively excite phonons. which enable either reversal of entire domains, the shift of domain walls and/or the broadening of the domain wall widths. (C) 2003 Elsevier B.V. All rights reserved. (Less)

We have observed large-amplitude strain waves following a rapid change in density of InSb due to nonthermal melting. The strain has been measured in real time via time-resolved x-ray diffraction, with a temporal resolution better than 2 ps. The change from the solid to liquid density of the surface layer launches a high-amplitude strain wave into the crystalline material below. This induces an effective plane rotation in the asymmetrically cut crystal leading to deflection of the diffracted beam. The uniform strain in the layer below the molten layer is 2.0(+/-0.2)%. A strain of this magnitude develops within 5 ps of the incident pulse showing that the liquid has reached the equilibrium density within this time frame. Both the strain amplitude and the depth of the strained material in the solid can be explained by assuming a reduction in the speed of sound in the nonequilibrium liquid compared to measured equilibrium values.

The motion of atoms on interatomic potential energy surfaces is fundamental to the dynamics of liquids and solids. An accelerator-based source of femtosecond x-ray pulses allowed us to follow directly atomic displacements on an optically modified energy landscape, leading eventually to the transition from crystalline solid to disordered liquid. We show that, to first order in time, the dynamics are inertial, and we place constraints on the shape and curvature of the transition-state potential energy surface. Our measurements point toward analogies between this nonequilibrium phase transition and the short-time dynamics intrinsic to equilibrium liquids.

We investigated phonon-phonon interactions in photoexcited single-crystalline graphite by ultrafast electron diffraction. Transient electron diffraction profiles from a 35 nm graphite film were observed following laser excitation. Changes in intensities of diffraction spots revealed a two-exponential relaxation process with

För att spara tid och pengar i ett utvecklingsskede av en applikation, kan med fördel redan befintliga teknologier användas. För att skapa en arkivapplikation där användaren kan titta på och tanka hem arkiverat material utan för stora tidsförluster så krävs teknologier som klarar detta. Teknologin måste även klara av att hantera stora mängder data då arkivering av webben gör att datamängderna i arkivet hela tiden ökar. En teknologi som uppfyller kriterierna i OAIS-modellen som är en standard för arkivering och som kan hantera stora mängder data är NoSQL-databaser. Dessa finns i olika utföranden och är olika svåra att hantera. Denna studie har fokuserat på två populära dokumentbaserade NoSQL-databaser som är lätta att installera och relativt enkla att hantera. Vilken av dessa två NoSQL-databaser är då lämpligast för en applikation som skall lagra webbinnehåll? Frågan besvaras genom ett experiment vars inriktning är att utröna hur de två NoSQL-databaserna fungerar som arkivmedium. Utifrån studiens analys kan svaret ges att de fungerar olika bra i olika situationer. Skall applikationen användas för att lagra relativt små filer i form av PDF eller TXT så är MongoDB det bästa valet av de två. Om det däremot skall hanteras större filer så är CouchDB det bättre valet.

In this paper, we present the investigation and characterization of the laser-induced surface structure on an asymmetrically cut InSb crystal. We describe diffraction from the ripple surface and present a theoretical model that can be used to simulate X-ray energy scans. The asymmetrically cut InSb sample was irradiated with short-pulse radiation centred at 800 nm, with fluences ranging from 10 to 80 mJ/cm(2). The irradiated sample surface profile was investigated using optical and atomic force microscopy. We have investigated how laser-induced ripples influence the possibility of studying repetitive melting of solids using X-ray diffraction. The main effects arise from variations in local asymmetry angles, which reduce the attenuation length and increase the X-ray diffraction efficiency.

Preeclampsia is a major cause of morbidity and mortality during pregnancy. To date, the pathogenesis of the disease is not fully understood. Recent studies show that preeclampsia is associated with overexpression of the hemoglobin genes alpha2 and gamma and accumulation of the protein in the vascular lumen of the placenta. Hypothesizing that cell-free hemoglobin leaks from the placenta into the maternal circulation and contributes to the endothelial damage and symptoms by inducing oxidative stress, we analyzed fetal and adult hemoglobin (HbF, HbA), haptoglobin, oxidation markers, and the heme scavenger and antioxidant alpha(1)-microglobulin in plasma, urine, and placenta in preeclamptic women (n=28) and women with normal pregnancy (n=27). The mean plasma concentrations of HbF, HbA, protein carbonyl groups, membrane peroxidation capacity, and alpha(1)-microglobulin were significantly increased in preeclamptic women. The levels of total plasma Hb correlated strongly with the systolic blood pressure. The plasma haptoglobin concentrations of women with preeclampsia were significantly depressed. Increased amounts of alpha(1)-microglobulin mRNA and protein were found in placenta from preeclamptic women, and the levels of plasma and placenta alpha(1)-microglobulin correlated with the plasma Hb concentrations. The heme-degrading form t-alpha(1)-microglobulin was significantly increased in urine in preeclampsia. These results support the idea that hemoglobin-induced oxidative stress is a pathogenic factor in preeclampsia.

The dynamics of particle formation were investigated for a diffusion-like ethylene flame containing a cooling metal plate on which particles condensed. Small-angle and wide-angle X-ray scattering techniques were combined to follow size- and structural changes of the soot particles using a new detector. The high dynamic range allowed continuous monitoring from the gas to the condensed phase of the gradually growing layer depositing on the plate. Different stages in the process of particle formation were observed. In addition the sub-nanometer structure of the deposited material changed rapidly as the flame was turned off. The detection system and methodology presented are of general interest since they can be further developed and applied to the study of reactive systems for materials processing in gas- and condensed phases.

Two perfluorocarbon liquids (perfluoro-n-octane and perfluorodecaline) were evaluated as technical aids in vitreoretinal surgery in 42 patients. Perfluorocarbon liquids were found to stabilize the retina and simplify removal of repiretinal membranes, which in many cases permitted the subsequent use of an expanding gas instead of silicone oil at the conclusion of the operation. The infusion of a perfluorocarbon liquids allowed the drainage of subretinal fluid through peripheral retinal breaks obviating the need for a retinotomy in most cases. No difference could be observed between the two types of perfluorocarbon liquids, and there were no adverse effects associated with their use. The retina was centrally attached in 32 eyes (76%) at 3-10 months follow-up.

PurposeThe purpose of this paper is to describe the adaptation and programme development of the Strengthening Families Programme to a Swedish setting.Design/methodology/approachA descriptive approach was employed with a focus on the cultural adaptation and programme development. This included meetings with two reference groups, a telephone interview with parents, translation of materials and production of videos and manuals. A pilot study was conducted which included course evaluations by students and parents, meetings with teachers and group leaders and a focus group interview with parents.FindingsThe programme format was altered in the Swedish version so that the youth sessions were held earlier during the day and the parent sessions later in the evening. Instead of having one family session at every meeting, the Swedish version included two family sessions in all. In the Swedish version, the booster sessions were incorporated as a regular part of the programme. In addition, more emphasis on alcohol and other drugs was added as well as an extra session. Following the evaluation of the pilot study, the materials were revised, with the inclusion of a “milder” vocabulary concerning disciplinary matters.Practical implicationsIt seems to be possible to disseminate the core elements in family programmes between different cultures, especially if care is taken to make adjustments to local conditions.Originality/valueThis paper makes a contribution to the research on how to culturally adapt prevention programmes.

Aim: The efficacy and safety of repeated injections of intravitreal triamcinolone (IVTA) for diabetic macular oedema is unclear, with results of previous reports conflicting. Methods: This is a prospective, observational case series of 27 eyes receiving IVTA for diabetic macular oedema. LogMAR visual acuity (VA) and central macular thickness (CMT) were measured at baseline and in 3 to 6 monthly intervals for up to 24 months, then correlated with the number of IVTA injections given. Results: One IVTA injection was required in 6 (18%) eyes, 2 in 8 (24%) eyes, 3 in 13 (39%) eyes and 4–5 in 6 (18%) eyes. VA improved in all patients, but neither the final improvement in VA nor the absolute improvement in CMT from baseline to 24 months correlated with the number of injections received (p = 0.44 and 0.84, respectively). Cataract surgery was more frequent in eyes receiving more injections (p = 0.01). Conclusions: This study suggests that repeated injections of IVTA continue to be as effective as the first over a 2-year period. The probability of cataract surgery increases with an increasing number of injections.

To study the relationship between foveal thickness assessed by optical coherence tomography (OCT) and foveal function measured with multi focal electroretinography (mfERG) in patients with non-proliferative diabetic retinopathy, and with no previous laser treatment.Twenty-six eyes from 18 diabetic patients (13 men), aged 59 years, (range 28-79 years), diabetes duration 15 years, (range 2-27 years), with a macular thickness between 200 and 600 microm were evaluated by mfERG, visual acuity (ETDRS score) and OCT. Mean amplitudes and implicit times of the mfERG responses were analyzed within the four innermost (14 degrees) of the six concentric rings. For comparison with the results from the OCT (diameter of measured area = 6 mm) we analyzed the summed response from the first and second ring (central zone), corresponding to the central area of the OCT. The third(zone 2) and fourth (zone 3)of the four innermost of the six concentric rings measured by the mfERG corresponding to the second and third area of OCT.An increased macular thickness in the central area of the OCT correlated to reduced amplitudes (r = -0.541; P = 0.004) and prolonged implicit times (r = 0.548; P = 0.004) in the central zone of the mfERG, and inversely correlated with visual acuity, -0.49; P = 0.045. Retinal thickness in the second area was correlated to prolonged implicit times in the second mfERG zone (r = -0.416; P = 0.034). No correlations were found for the third area of the OCT. When macular thickness exceeded 300 mum the decrease of amplitudes and prolonged implicit times, measured by mfERG, seemed to be more pronounced.In conclusion increased macular thickness is correlated with reduced amplitudes and prolonged implicit times on the mf ERG and worse visual acuity.