This paper examines the spatial and temporal distribution of all COVID-19 cases from January to June 2020 against the underlying distribution of population in the United States.It is found that,as time passes,COVID-19...This paper examines the spatial and temporal distribution of all COVID-19 cases from January to June 2020 against the underlying distribution of population in the United States.It is found that,as time passes,COVID-19 cases become a power law with cutoff,resembling the underlying spatial distribution of populations.The power law implies that many states and counties have a low number of cases,while only a few highly populated states and counties have a high number of cases.To further differentiate patterns between the underlying populations and COVID-19 cases,we derived their inherent hierarchy or spatial heterogeneity characterized by the ht-index.We found that the ht-index of COVID-19 cases persistently approaches that of the populations;that is,5 and 7 at the state and county levels,respectively.Mapping the ht-index of COVID-19 cases against that of populations shows that the pandemic is largely shaped by the underlying population with the R-square value between infection and population up to 0.82.展开更多
The results of global and regional studies often show significant disagreement between the Moho depths determined using seismic and isostatic models. In this study, we estimate the differences between these two models...The results of global and regional studies often show significant disagreement between the Moho depths determined using seismic and isostatic models. In this study, we estimate the differences between these two models in central Eurasia. The Vening Meinesz-Moritz （VMM） inverse problem of isostasy is utilized to determine the isostatic Moho depths. The estimated VMM Moho depths are then corrected for the sediment density contrast. The application of this correction improves the agreement between the isostatic and seismic Moho models. The existing discrepancies between the isostatic and seismic models are finally modeled by applying the non-isostatic correction, which accounts for the unmodelled mantle density heterogeneities and other geodynamic processes, which are not taken into account in classical isostatic models. Our results reveal that the non-isostatic correction still cannot fully describe mechanisms affecting the Moho geometry along the convergent continent-tocontinent tectonic plate boundaries occurring beneath Himalayas despite an overall good performance of the applied method.展开更多
We provide estimates of glacier mass changes in the High Mountain Asia (HMA) area from April2002 to August 2016 by employing a new version of gravity solutions of the Gravity Recovery and ClimateExperiment (GRACE) twi...We provide estimates of glacier mass changes in the High Mountain Asia (HMA) area from April2002 to August 2016 by employing a new version of gravity solutions of the Gravity Recovery and ClimateExperiment (GRACE) twin-satellite mission. We find a total mass loss trend of the HMA glaciers at a rateof –22.17 (±1.96) Gt/a. The largest mass loss rates of –7.02 (±0.94) and –6.73 (±0.78) Gt/a are found forthe glaciers in Nyainqentanglha Mountains and Eastern Himalayas, respectively. Although most glaciers inthe HMA area show a mass loss, we find a small glacier mass gain of 1.19 (±0.55) and 0.77 (±0.37) Gt/a inKarakoram Mountains and Western Kunlun Mountains, respectively. There is also a nearly zero massbalance in Pamirs. Our estimates of glacier mass change trends confirm previous results from the analysisof altimetry data of the ICESat (ICE, Cloud and Land Elevation Satellite) and ASTER (AdvancedSpaceborne Thermal Emission and Reflection Radiometer) DEM (Digital Elevation Model) satellites inmost of the selected glacier areas. However, they largely differ to previous GRACE-based studies which weattribute to our different post-processing techniques of the newer GRACE data. In addition, we explicitlyshow regional mass change features for both the interannual glacier mass changes and the 14-a averagedseasonal glacier mass changes. These changes can be explained in parts by total net precipitation (netsnowfall and net rainfall) and net snowfall, but mostly by total net radiation energy when compared to datafrom the ERA5-Land meteorological reanalysis. Moreover, nearly all the non-trend interannual masschanges and most seasonal mass changes can be explained by the total net radiation energy data. The massloss trends could be partly related to a heat effect due to increased net rainfall in Tianshan Mountains, QilianMountains, Nyainqentanglha Mountains and Eastern Himalayas. Our new results for the glacier mass changein this study could help improve the understanding of glacier variation in the HMA area and contribute tothe study of global change. They could also serve the utilization of water resources there and in neighboringareas.展开更多
According to Vening Meinesz-Moritz （VMM） global inverse isostatic problem, either the Moho density contrast （crust-mantle density contrast） or the Moho geometry can be estimated by solv- ing a non-linear Fredholm ...According to Vening Meinesz-Moritz （VMM） global inverse isostatic problem, either the Moho density contrast （crust-mantle density contrast） or the Moho geometry can be estimated by solv- ing a non-linear Fredholm integral equation of the first kind. Here solutions to the two Moho parame- ters are presented by combining the global geopotential model （GOCO-03S）, topography （DTM2006） and a seismic crust model, the latter being the recent digital global crustal model （CRUST1.0） with a resolution of 1°×1°. The numerical results show that the estimated Moho density contrast varies from 21 to 637 kg/m3, with a global average of 321 kg/m^3, and the estimated Moho depth varies from 6 to 86 km with a global average of 24 km. Comparing the Moho density contrasts estimated using our least-squares method and those derived by the CRUST1.0, CRUST2.0, and PREM models shows that our estimate agrees fairly well with CRUST1.0 model and rather poor with other models. The estimated Moho depths by our least-squares method and the CRUST1.0 model agree to 4.8 km in RMS and with the GEMMA1.0 based model to 6.3 km.展开更多
Day care services for persons with dementia are becoming an important aspect of community services. Place, therefore, becomes vital concerning how such establishments are organized regarding both the physical and soci...Day care services for persons with dementia are becoming an important aspect of community services. Place, therefore, becomes vital concerning how such establishments are organized regarding both the physical and social environment and the programs that are offered. The aim of this study was to describe the influence of place on everyday life in two different organized daycare services for persons with dementia. Based on observations and informal conversations with persons with dementia and staff members at a green care farm and a regular day care, we used an inductive manifest content analysis. The analysis reveals a main category: enabling and collaboration in daily life. The results are discussed in light of Goffman’s analysis of the structures of social encounters from the perspective of the dramatic performance. The main findings in this study involve how place contributes to enabling activities and collaboration between participants and staff, as it influences participants’ ability to achieve an active or passive role in everyday life at the day care services.展开更多
Knowledge about the structure and development of wakes behind wind turbines is important for power optimization of wind power farms. The high turbulence levels in the wakes give rise to undesired unsteady loadings on ...Knowledge about the structure and development of wakes behind wind turbines is important for power optimization of wind power farms. The high turbulence levels in the wakes give rise to undesired unsteady loadings on the downstream turbines, which in the long run might cause fatigue damages. In the present study, the near wake behind a small-scale model wind turbine was investigated experimentally in a wind tunnel. The study consists of measurements with particle image velocimetry using two different inlet conditions: a freely developing boundary layer, causing an almost uniform inflow across the rotor disc, and an inflow with strong shear across the rotor disc, in order to model the atmospheric boundary layer. The results show a faster recovery of the wake in the case with shear inflow, caused by the higher turbulence levels and enhanced mixing of momentum. The increased inlet turbulence levels in this case also resulted in a faster breakdown of the tip vortices as well as different distributions of the streamwise and vertical components of the turbulence intensity in the wake. An analysis comparing vortex statistics for the two cases also showed the presence of strong tip vortices in the case with lower inlet turbulence, while the case with higher inlet turbulence developed a different distribution of vortices in the wake.展开更多
Two key goals for sustainable spatial planning are to promote low-carbon travel in daily life and to enhance human wellbeing through diverse human-environment interactions.Yet,the integration of these goals has been u...Two key goals for sustainable spatial planning are to promote low-carbon travel in daily life and to enhance human wellbeing through diverse human-environment interactions.Yet,the integration of these goals has been underexplored.This study investigates the potential for experiential diversity via active travel in different resi-dential contexts within the Gävle city-region,Sweden.Over 15 months,we collected spatiotemporal data from 165 participants,analyzing 4,362 reported experiences and 13,192 GPS-derived travel trajectories.Our analysis uncovered a significant spatial discrepancy:while the travelled distances to locations of positive experiences typ-ically ranged from 1.5 km to 5 km,active travel predominated only within 1.5 km.This discrepancy persisted across urban,suburban,and peripheral contexts.Although residents in different contexts reported the same types of experiences,urban dwellers travelled about 50%farther for nature experiences compared with other positive experiences,whereas peripheral dwellers travelled twice the distance for urbanicity experiences compared with other positive experiences.Consequently,urban residents mostly relied on active travel for urbanicity experiences and motorised travel for nature experiences,with the reverse trend observed among peripheral dwellers.These results illustrate the importance of spatial scale for promoting diverse positive experiences via active travel,re-gardless of residential context.Effective planning strategies may include enhancing environmental diversity near homes and developing infrastructure that favours active over motorised travel for short to moderate distances.展开更多
<strong>Background:</strong> Worldwide, prostatic adenocarcinoma is the most common tumour type among men. <strong>Aim:</strong> The aim of the present investigation was to develop a computer p...<strong>Background:</strong> Worldwide, prostatic adenocarcinoma is the most common tumour type among men. <strong>Aim:</strong> The aim of the present investigation was to develop a computer program to identify normal prostate biopsies and distinguish them from biopsies showing premalignant alterations (LGPIN, HGPIN) and adenocarcinoma. <strong>Method:</strong> Prostate biopsies (n = 2094) taken from 191 consecutive men during 2016 were stained with triple immunehistochemisty (antibodies to AMACRA, p63 and CK 5). Digital images of the biopsies were obtained with a scanning microscope and used to develop an automatic computer program (CelldaTM), intended to identify the morphological alterations. Visual microscopic finding was used as a reference. <strong>Result:</strong> Of the 191 men, 121 (63.4%) were diagnosed as having prostate adenocarcinoma and 70 (36.6%) as having no malignancy on the basis of the visual microscopy. In comparison, computer analysis identified 134 (70.2%) men with malignant disease and 57 (29.8%) with non-malignant disease after exclusion of artifacts, which constituted 10.4% of areas (indicated as malignant disease). Discrepant results were recorded in 15 (7.9%) men, and in 14 of these cases, HGPIN and areas suggestive of early invasion were common. Thus, it was uncertain whether these cases should be regarded as malignant or not. The agreement between the visual examination and the computer analysis was 92.1% (kappa value 0.823, sensitivity 99.2 and specificity was 0.80). <strong>Conclusion:</strong> It seems that computer analysis could serve as an adjunct to simplify and shorten the diagnostic procedure, first of all by ensuring that normal prostate biopsies are sorted out from those sent for visual microscopic evaluation.展开更多
Wind tunnel measurements using particle image velocimetry have been performed around two perforated discs, with varying streamwise distance, in order to simulate the wake interaction between wind turbines. The static ...Wind tunnel measurements using particle image velocimetry have been performed around two perforated discs, with varying streamwise distance, in order to simulate the wake interaction between wind turbines. The static pressure footprint (p-f) on ground level associated with the wake behind the disc and wake velocity data for both the streamwise and wall-normal velocity components with the corresponding turbulence intensities are reported. The p-f method shows that the size of the wake regions, behind the wind turbine models, initially drop when a second disc is placed just downstream of the first one. From a mutual distance (Δ χ) of about five disc diameters (5D), both wake footprints increase as the mutual distance is increased, and for very large mutual distances, approximately Δ χ/ D > 15, the footprint of the downstream disc has recovered and is about the same as for a single disc. At last we conclude that despite very different inlet conditions to the discs, with about 50% of reduced velocity on the centre line upstream of the second disc and an increase of the maximum streamwise fluctuations by 90%, the mean velocities in the wake are proven to scale with the hub height velocity.展开更多
Background: The functionality and the safety of the electric wheelchairs were essential for users’ everyday life. Some evidence indicated that the wheelchair Per Se highly influenced users’ occupational life, their ...Background: The functionality and the safety of the electric wheelchairs were essential for users’ everyday life. Some evidence indicated that the wheelchair Per Se highly influenced users’ occupational life, their personal identity and social life;further, the wheelchair became an extension of the body and more than a technical device. Besides, there was still both environmental and self-efficacy or/and mental health factors obstacles for full social participation. Even so, there was to some extent stigma related to being a wheelchair user. There was a need to reflect users’ perspective on being depended on electric wheelchair. The aim, accordingly, was to describe and to get a deeper insight into electric wheelchairs users’ perspective and experiences of utilizing this device;a qualitative design with an inductive approach was used. Method: Qualitative latent and interpretative content analysis [1] [2] was used after repeated face-to-face semi-structured interviews with three experienced Swedish electric wheelchair users during the autumn 2017. Findings: The findings showed a high degree of dependability of the assistants that supported the users, and of the quality of that working relationship. The findings were formulated, abstracted and interpreted in several steps. It showed one theme of meaning: “Living in a space shifting between potential violation of or respect for human dignity”. Conclusion: The study showed that electric wheelchair users were relatively content with their lives as well as with their devices in turns of mobility and accessibility, but the meaning of their narrations showed a life at constant risk of having the respect of human rights and human respect violated. Besides, the importance of having access to good and high quality devices, good staffing, and environmental support, all in concordance with human rights, the clinical and practical implications of this study narrows down to a question of encountering the other person as a whole and worthy individual.展开更多
Background: Today’s parents belong to the digital generation and regularly use the Internet as a source of information. Parents’ quests for health-related online information comprise an effort to manage symptoms of ...Background: Today’s parents belong to the digital generation and regularly use the Internet as a source of information. Parents’ quests for health-related online information comprise an effort to manage symptoms of illness or address questions about child development which may be an expression of self-management or self-care. Purpose: This study aims to describe health and child development related Internet search patterns used by parents of children ages zero to six, and further, how the obtained information was used in contacts with Child Health Care. Design and Methods: A two-step mixed- method approach is used in this study, comprising both a quantitative and a qualitative approach. First, a questionnaire was distributed to parents (n = 800) at 13 health centers in a medium sized county in Sweden. Second, one narrative interview with two parents total was conducted. Descriptive and non-parametric statistics were calculated, and qualitative manifest content analyses were performed. Results: A total of 687 completed the questionnaire, which corresponds to a response rate of 86%. The results show that 97% used the Internet for health-related and developmental child issues. The results show that parents often look at basic tips and the Internet is seen as a fast and accessible forum to obtain information. Parents often initiated their Internet searches using Google search for the specific subject, but the most common and most used website (used by 95% of parents), was the Swedish health site 1177.se. 98.4% of parents evaluated the general information searches they made on the Internet as reliable despite only 31% of the parents checking to see if the websites they used were scientifically based. Parents (81.7%) stated that they wanted their Child Health Nurses (CHN) to give them recommendations for valid websites. Conclusions: The results in this study show that, on the one hand, the Internet could strengthen parental knowledge (support self-care capacity), but, on the other hand, the found information could worry them and increase their anxiety—negatively affected self-care capacity. The parents suggested that the information should be double-checked to establish trust and develop self-care knowledge. Having a good resource to rely on, such as personal contact with a CHN, or using reliable websites seems to strengthen and reassure parents.展开更多
Most members of the older population in Thailand live in rural areas while their children live in cities. With the joint family system separated, elderly Thai persons often have to care for themselves, and opportuniti...Most members of the older population in Thailand live in rural areas while their children live in cities. With the joint family system separated, elderly Thai persons often have to care for themselves, and opportunities for them to get involved in community care remain limited. In response, the aim of this study was to describe older persons’ and their family members’ experiences with shareholding networks for the care of older people in rural Thailand. Paired interviews with five older persons and five of their family members were conducted, and collected data were subjected to content analysis, which yielded results organized around two themes: older persons’ outsider status and disregard for older persons’ individuality. Whereas the theme of outsider status describes shortcomings in healthcare encounters, the theme of disregard for individuality describes the lack of engagement of authorities and caregivers in older persons’ care. In that sense, the concept of participation emerged as a framework for understanding interviewees’ experiences. Given findings from local authorities, older individuals and their family members should engage in dialogue in order to support healthcare based on shared understanding.展开更多
To extend the PSRK (predictive Soave-Redlich-Kwong equation of state) model to vapor-liquid equilibria of polymer solutions, a new EOS-gE mixing rule is applied in which the term ∑ xi ln(b/bi) in the PSRK mixing rule...To extend the PSRK (predictive Soave-Redlich-Kwong equation of state) model to vapor-liquid equilibria of polymer solutions, a new EOS-gE mixing rule is applied in which the term ∑ xi ln(b/bi) in the PSRK mixing rule for the parameter a, and the combinatorial part in the original universal functional activity coefficient (UNIFAC) model are cancelled. To take into account the free volume contribution to the excess Gibbs energy in polymer solution, a quadratic mixing rule for the cross co-volume bij with an exponent equals to 1/2 is applied[bij1/2= 1/2(bi1/2+bj1/2)]. The literature reported Soave-Redlich-Kwong equation of state (SRK EOS) parameters ofpure polymer are employed. The PSRK model with the modified mixing rule is used to predict the vapor-liquid equilibrium (VLE) of 37 solvent-polymer systems over a large range of temperature and pressure with satisfactory results.展开更多
The paper reports the monitoring for pesticide residue contamination of foodstuffs carried out in the years 1988-1989 by the Italian peripheral laboratories officially commissioned for the task. The tables show the an...The paper reports the monitoring for pesticide residue contamination of foodstuffs carried out in the years 1988-1989 by the Italian peripheral laboratories officially commissioned for the task. The tables show the analytical data for each class of substrate versus the limits in force at the time. 2506 food samples and 555 samples from the environment were analysed and a total of 16259 determinations made.The residues were absent in 90% of the cases; the percentage of irregularities was 1.52%. These results confirm the data obtained in previous years, which is particularly significant considering the much larger number of analytical determinations performed this time.It has been deemed convenient to survey specific types of foodstuffs (for example, cereals and animal products) by examining a larger number of samples.展开更多
The failure risk of defected reinforced concrete(RC)beams is considered a potential threat.This risk is experimentally identified,numerically analyzed,and thoroughly diminished to enhance structural safety and sustain...The failure risk of defected reinforced concrete(RC)beams is considered a potential threat.This risk is experimentally identified,numerically analyzed,and thoroughly diminished to enhance structural safety and sustainability to mitigate the potential for structural collapse during construction.This research investigates the efficacy of an external post-tensioning mechanism in enhancing the behavior of defected RC beams lacking shear reinforcement,employing both experimental and numerical approaches.Fourteen RC beams were tested to evaluate the impact of posttensioning force levels and the inclination angle of post-tensioning bars.The study found that regardless of force magnitude or angle,post-tensioning improved the failure characteristics of the non-stirrup beam.The failure mode transitioned from brittle to ductile,resulting in a more advantageous distribution of cracks.Reinforced beams exhibited increased cracking and ultimate loads,with the enhancement more pronounced at higher post-tensioning force levels.Inclined post-tensioning at angles of 75°,60°,and 45°demonstrated substantial enhancement in cracking and ultimate loads,as well as elastic stiffness.The findings highlighted the superiority of inclined post-tensioning configurations,especially at 60°,for reinforced beams.Moreover,the study revealed a significant increase in absorbed energy with the proposed strengthening system.Additionally,finite element modelling(FEM)was used to replicate the tested beams.FEM accurately predicted the crack development,ultimate capacity,and deformation,aligning well with experimental observations.展开更多
基金This work was partially supported by the Swedish Research Council Formas through the ALEXANDER project with grant number FR-2017/0009.
文摘This paper examines the spatial and temporal distribution of all COVID-19 cases from January to June 2020 against the underlying distribution of population in the United States.It is found that,as time passes,COVID-19 cases become a power law with cutoff,resembling the underlying spatial distribution of populations.The power law implies that many states and counties have a low number of cases,while only a few highly populated states and counties have a high number of cases.To further differentiate patterns between the underlying populations and COVID-19 cases,we derived their inherent hierarchy or spatial heterogeneity characterized by the ht-index.We found that the ht-index of COVID-19 cases persistently approaches that of the populations;that is,5 and 7 at the state and county levels,respectively.Mapping the ht-index of COVID-19 cases against that of populations shows that the pandemic is largely shaped by the underlying population with the R-square value between infection and population up to 0.82.
基金financial support (No.214273812)supported by the Swedish National Space Board (SNSB) (No.76/10:1)
文摘The results of global and regional studies often show significant disagreement between the Moho depths determined using seismic and isostatic models. In this study, we estimate the differences between these two models in central Eurasia. The Vening Meinesz-Moritz （VMM） inverse problem of isostasy is utilized to determine the isostatic Moho depths. The estimated VMM Moho depths are then corrected for the sediment density contrast. The application of this correction improves the agreement between the isostatic and seismic Moho models. The existing discrepancies between the isostatic and seismic models are finally modeled by applying the non-isostatic correction, which accounts for the unmodelled mantle density heterogeneities and other geodynamic processes, which are not taken into account in classical isostatic models. Our results reveal that the non-isostatic correction still cannot fully describe mechanisms affecting the Moho geometry along the convergent continent-tocontinent tectonic plate boundaries occurring beneath Himalayas despite an overall good performance of the applied method.
基金This work is funded by the National Key R&D Program of China(2017YFA0603103)the National Natural Science Foundation of China(41974009,42004007)+1 种基金the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(QYZDB-SSW-DQC027,QYZDJ-SSW-DQC042)the open fund of State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2021-2-6)。
文摘We provide estimates of glacier mass changes in the High Mountain Asia (HMA) area from April2002 to August 2016 by employing a new version of gravity solutions of the Gravity Recovery and ClimateExperiment (GRACE) twin-satellite mission. We find a total mass loss trend of the HMA glaciers at a rateof –22.17 (±1.96) Gt/a. The largest mass loss rates of –7.02 (±0.94) and –6.73 (±0.78) Gt/a are found forthe glaciers in Nyainqentanglha Mountains and Eastern Himalayas, respectively. Although most glaciers inthe HMA area show a mass loss, we find a small glacier mass gain of 1.19 (±0.55) and 0.77 (±0.37) Gt/a inKarakoram Mountains and Western Kunlun Mountains, respectively. There is also a nearly zero massbalance in Pamirs. Our estimates of glacier mass change trends confirm previous results from the analysisof altimetry data of the ICESat (ICE, Cloud and Land Elevation Satellite) and ASTER (AdvancedSpaceborne Thermal Emission and Reflection Radiometer) DEM (Digital Elevation Model) satellites inmost of the selected glacier areas. However, they largely differ to previous GRACE-based studies which weattribute to our different post-processing techniques of the newer GRACE data. In addition, we explicitlyshow regional mass change features for both the interannual glacier mass changes and the 14-a averagedseasonal glacier mass changes. These changes can be explained in parts by total net precipitation (netsnowfall and net rainfall) and net snowfall, but mostly by total net radiation energy when compared to datafrom the ERA5-Land meteorological reanalysis. Moreover, nearly all the non-trend interannual masschanges and most seasonal mass changes can be explained by the total net radiation energy data. The massloss trends could be partly related to a heat effect due to increased net rainfall in Tianshan Mountains, QilianMountains, Nyainqentanglha Mountains and Eastern Himalayas. Our new results for the glacier mass changein this study could help improve the understanding of glacier variation in the HMA area and contribute tothe study of global change. They could also serve the utilization of water resources there and in neighboringareas.
文摘According to Vening Meinesz-Moritz （VMM） global inverse isostatic problem, either the Moho density contrast （crust-mantle density contrast） or the Moho geometry can be estimated by solv- ing a non-linear Fredholm integral equation of the first kind. Here solutions to the two Moho parame- ters are presented by combining the global geopotential model （GOCO-03S）, topography （DTM2006） and a seismic crust model, the latter being the recent digital global crustal model （CRUST1.0） with a resolution of 1°×1°. The numerical results show that the estimated Moho density contrast varies from 21 to 637 kg/m3, with a global average of 321 kg/m^3, and the estimated Moho depth varies from 6 to 86 km with a global average of 24 km. Comparing the Moho density contrasts estimated using our least-squares method and those derived by the CRUST1.0, CRUST2.0, and PREM models shows that our estimate agrees fairly well with CRUST1.0 model and rather poor with other models. The estimated Moho depths by our least-squares method and the CRUST1.0 model agree to 4.8 km in RMS and with the GEMMA1.0 based model to 6.3 km.
文摘Day care services for persons with dementia are becoming an important aspect of community services. Place, therefore, becomes vital concerning how such establishments are organized regarding both the physical and social environment and the programs that are offered. The aim of this study was to describe the influence of place on everyday life in two different organized daycare services for persons with dementia. Based on observations and informal conversations with persons with dementia and staff members at a green care farm and a regular day care, we used an inductive manifest content analysis. The analysis reveals a main category: enabling and collaboration in daily life. The results are discussed in light of Goffman’s analysis of the structures of social encounters from the perspective of the dramatic performance. The main findings in this study involve how place contributes to enabling activities and collaboration between participants and staff, as it influences participants’ ability to achieve an active or passive role in everyday life at the day care services.
文摘Knowledge about the structure and development of wakes behind wind turbines is important for power optimization of wind power farms. The high turbulence levels in the wakes give rise to undesired unsteady loadings on the downstream turbines, which in the long run might cause fatigue damages. In the present study, the near wake behind a small-scale model wind turbine was investigated experimentally in a wind tunnel. The study consists of measurements with particle image velocimetry using two different inlet conditions: a freely developing boundary layer, causing an almost uniform inflow across the rotor disc, and an inflow with strong shear across the rotor disc, in order to model the atmospheric boundary layer. The results show a faster recovery of the wake in the case with shear inflow, caused by the higher turbulence levels and enhanced mixing of momentum. The increased inlet turbulence levels in this case also resulted in a faster breakdown of the tip vortices as well as different distributions of the streamwise and vertical components of the turbulence intensity in the wake. An analysis comparing vortex statistics for the two cases also showed the presence of strong tip vortices in the case with lower inlet turbulence, while the case with higher inlet turbulence developed a different distribution of vortices in the wake.
基金supported by funding provided by University of Gävle and Vinnova through the GeoLife Region project coordinated by Future Position X[2019-05068]K.S.was supported by a grant from Forte[2022-00841]+3 种基金S.B.was supported by a joint grant from Mistra[DIA 2019/28]Formas via the national research programme on cli-mate[2021-00416]called FAIRTRANSWe acknowledge support from the project Cycle4Climate(Grant No.CB0300173)funded by Interreg Europe’s Central Baltic programme,that inspired and enriched this paper.
文摘Two key goals for sustainable spatial planning are to promote low-carbon travel in daily life and to enhance human wellbeing through diverse human-environment interactions.Yet,the integration of these goals has been underexplored.This study investigates the potential for experiential diversity via active travel in different resi-dential contexts within the Gävle city-region,Sweden.Over 15 months,we collected spatiotemporal data from 165 participants,analyzing 4,362 reported experiences and 13,192 GPS-derived travel trajectories.Our analysis uncovered a significant spatial discrepancy:while the travelled distances to locations of positive experiences typ-ically ranged from 1.5 km to 5 km,active travel predominated only within 1.5 km.This discrepancy persisted across urban,suburban,and peripheral contexts.Although residents in different contexts reported the same types of experiences,urban dwellers travelled about 50%farther for nature experiences compared with other positive experiences,whereas peripheral dwellers travelled twice the distance for urbanicity experiences compared with other positive experiences.Consequently,urban residents mostly relied on active travel for urbanicity experiences and motorised travel for nature experiences,with the reverse trend observed among peripheral dwellers.These results illustrate the importance of spatial scale for promoting diverse positive experiences via active travel,re-gardless of residential context.Effective planning strategies may include enhancing environmental diversity near homes and developing infrastructure that favours active over motorised travel for short to moderate distances.
文摘<strong>Background:</strong> Worldwide, prostatic adenocarcinoma is the most common tumour type among men. <strong>Aim:</strong> The aim of the present investigation was to develop a computer program to identify normal prostate biopsies and distinguish them from biopsies showing premalignant alterations (LGPIN, HGPIN) and adenocarcinoma. <strong>Method:</strong> Prostate biopsies (n = 2094) taken from 191 consecutive men during 2016 were stained with triple immunehistochemisty (antibodies to AMACRA, p63 and CK 5). Digital images of the biopsies were obtained with a scanning microscope and used to develop an automatic computer program (CelldaTM), intended to identify the morphological alterations. Visual microscopic finding was used as a reference. <strong>Result:</strong> Of the 191 men, 121 (63.4%) were diagnosed as having prostate adenocarcinoma and 70 (36.6%) as having no malignancy on the basis of the visual microscopy. In comparison, computer analysis identified 134 (70.2%) men with malignant disease and 57 (29.8%) with non-malignant disease after exclusion of artifacts, which constituted 10.4% of areas (indicated as malignant disease). Discrepant results were recorded in 15 (7.9%) men, and in 14 of these cases, HGPIN and areas suggestive of early invasion were common. Thus, it was uncertain whether these cases should be regarded as malignant or not. The agreement between the visual examination and the computer analysis was 92.1% (kappa value 0.823, sensitivity 99.2 and specificity was 0.80). <strong>Conclusion:</strong> It seems that computer analysis could serve as an adjunct to simplify and shorten the diagnostic procedure, first of all by ensuring that normal prostate biopsies are sorted out from those sent for visual microscopic evaluation.
文摘Wind tunnel measurements using particle image velocimetry have been performed around two perforated discs, with varying streamwise distance, in order to simulate the wake interaction between wind turbines. The static pressure footprint (p-f) on ground level associated with the wake behind the disc and wake velocity data for both the streamwise and wall-normal velocity components with the corresponding turbulence intensities are reported. The p-f method shows that the size of the wake regions, behind the wind turbine models, initially drop when a second disc is placed just downstream of the first one. From a mutual distance (Δ χ) of about five disc diameters (5D), both wake footprints increase as the mutual distance is increased, and for very large mutual distances, approximately Δ χ/ D > 15, the footprint of the downstream disc has recovered and is about the same as for a single disc. At last we conclude that despite very different inlet conditions to the discs, with about 50% of reduced velocity on the centre line upstream of the second disc and an increase of the maximum streamwise fluctuations by 90%, the mean velocities in the wake are proven to scale with the hub height velocity.
文摘Background: The functionality and the safety of the electric wheelchairs were essential for users’ everyday life. Some evidence indicated that the wheelchair Per Se highly influenced users’ occupational life, their personal identity and social life;further, the wheelchair became an extension of the body and more than a technical device. Besides, there was still both environmental and self-efficacy or/and mental health factors obstacles for full social participation. Even so, there was to some extent stigma related to being a wheelchair user. There was a need to reflect users’ perspective on being depended on electric wheelchair. The aim, accordingly, was to describe and to get a deeper insight into electric wheelchairs users’ perspective and experiences of utilizing this device;a qualitative design with an inductive approach was used. Method: Qualitative latent and interpretative content analysis [1] [2] was used after repeated face-to-face semi-structured interviews with three experienced Swedish electric wheelchair users during the autumn 2017. Findings: The findings showed a high degree of dependability of the assistants that supported the users, and of the quality of that working relationship. The findings were formulated, abstracted and interpreted in several steps. It showed one theme of meaning: “Living in a space shifting between potential violation of or respect for human dignity”. Conclusion: The study showed that electric wheelchair users were relatively content with their lives as well as with their devices in turns of mobility and accessibility, but the meaning of their narrations showed a life at constant risk of having the respect of human rights and human respect violated. Besides, the importance of having access to good and high quality devices, good staffing, and environmental support, all in concordance with human rights, the clinical and practical implications of this study narrows down to a question of encountering the other person as a whole and worthy individual.
文摘Background: Today’s parents belong to the digital generation and regularly use the Internet as a source of information. Parents’ quests for health-related online information comprise an effort to manage symptoms of illness or address questions about child development which may be an expression of self-management or self-care. Purpose: This study aims to describe health and child development related Internet search patterns used by parents of children ages zero to six, and further, how the obtained information was used in contacts with Child Health Care. Design and Methods: A two-step mixed- method approach is used in this study, comprising both a quantitative and a qualitative approach. First, a questionnaire was distributed to parents (n = 800) at 13 health centers in a medium sized county in Sweden. Second, one narrative interview with two parents total was conducted. Descriptive and non-parametric statistics were calculated, and qualitative manifest content analyses were performed. Results: A total of 687 completed the questionnaire, which corresponds to a response rate of 86%. The results show that 97% used the Internet for health-related and developmental child issues. The results show that parents often look at basic tips and the Internet is seen as a fast and accessible forum to obtain information. Parents often initiated their Internet searches using Google search for the specific subject, but the most common and most used website (used by 95% of parents), was the Swedish health site 1177.se. 98.4% of parents evaluated the general information searches they made on the Internet as reliable despite only 31% of the parents checking to see if the websites they used were scientifically based. Parents (81.7%) stated that they wanted their Child Health Nurses (CHN) to give them recommendations for valid websites. Conclusions: The results in this study show that, on the one hand, the Internet could strengthen parental knowledge (support self-care capacity), but, on the other hand, the found information could worry them and increase their anxiety—negatively affected self-care capacity. The parents suggested that the information should be double-checked to establish trust and develop self-care knowledge. Having a good resource to rely on, such as personal contact with a CHN, or using reliable websites seems to strengthen and reassure parents.
文摘Most members of the older population in Thailand live in rural areas while their children live in cities. With the joint family system separated, elderly Thai persons often have to care for themselves, and opportunities for them to get involved in community care remain limited. In response, the aim of this study was to describe older persons’ and their family members’ experiences with shareholding networks for the care of older people in rural Thailand. Paired interviews with five older persons and five of their family members were conducted, and collected data were subjected to content analysis, which yielded results organized around two themes: older persons’ outsider status and disregard for older persons’ individuality. Whereas the theme of outsider status describes shortcomings in healthcare encounters, the theme of disregard for individuality describes the lack of engagement of authorities and caregivers in older persons’ care. In that sense, the concept of participation emerged as a framework for understanding interviewees’ experiences. Given findings from local authorities, older individuals and their family members should engage in dialogue in order to support healthcare based on shared understanding.
文摘To extend the PSRK (predictive Soave-Redlich-Kwong equation of state) model to vapor-liquid equilibria of polymer solutions, a new EOS-gE mixing rule is applied in which the term ∑ xi ln(b/bi) in the PSRK mixing rule for the parameter a, and the combinatorial part in the original universal functional activity coefficient (UNIFAC) model are cancelled. To take into account the free volume contribution to the excess Gibbs energy in polymer solution, a quadratic mixing rule for the cross co-volume bij with an exponent equals to 1/2 is applied[bij1/2= 1/2(bi1/2+bj1/2)]. The literature reported Soave-Redlich-Kwong equation of state (SRK EOS) parameters ofpure polymer are employed. The PSRK model with the modified mixing rule is used to predict the vapor-liquid equilibrium (VLE) of 37 solvent-polymer systems over a large range of temperature and pressure with satisfactory results.
文摘The paper reports the monitoring for pesticide residue contamination of foodstuffs carried out in the years 1988-1989 by the Italian peripheral laboratories officially commissioned for the task. The tables show the analytical data for each class of substrate versus the limits in force at the time. 2506 food samples and 555 samples from the environment were analysed and a total of 16259 determinations made.The residues were absent in 90% of the cases; the percentage of irregularities was 1.52%. These results confirm the data obtained in previous years, which is particularly significant considering the much larger number of analytical determinations performed this time.It has been deemed convenient to survey specific types of foodstuffs (for example, cereals and animal products) by examining a larger number of samples.
文摘The failure risk of defected reinforced concrete(RC)beams is considered a potential threat.This risk is experimentally identified,numerically analyzed,and thoroughly diminished to enhance structural safety and sustainability to mitigate the potential for structural collapse during construction.This research investigates the efficacy of an external post-tensioning mechanism in enhancing the behavior of defected RC beams lacking shear reinforcement,employing both experimental and numerical approaches.Fourteen RC beams were tested to evaluate the impact of posttensioning force levels and the inclination angle of post-tensioning bars.The study found that regardless of force magnitude or angle,post-tensioning improved the failure characteristics of the non-stirrup beam.The failure mode transitioned from brittle to ductile,resulting in a more advantageous distribution of cracks.Reinforced beams exhibited increased cracking and ultimate loads,with the enhancement more pronounced at higher post-tensioning force levels.Inclined post-tensioning at angles of 75°,60°,and 45°demonstrated substantial enhancement in cracking and ultimate loads,as well as elastic stiffness.The findings highlighted the superiority of inclined post-tensioning configurations,especially at 60°,for reinforced beams.Moreover,the study revealed a significant increase in absorbed energy with the proposed strengthening system.Additionally,finite element modelling(FEM)was used to replicate the tested beams.FEM accurately predicted the crack development,ultimate capacity,and deformation,aligning well with experimental observations.
