| 1. |
- Li, Furong, et al.
(author)
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A Review of Relative Pollen Productivity Estimates From Temperate China for Pollen-Based Quantitative Reconstruction of Past Plant Cover
- 2018
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In: Frontiers in Plant Science. - : Frontiers Media S.A.. - 1664-462X. ; 9
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Research review (peer-reviewed)abstract
- Model-based quantitative reconstruction of past plant cover in Europe has shown great potential for: (i) testing hypotheses related to Holocene vegetation dynamics, biodiversity, and their relationships with climate and land use; (ii) studying long term interactions between climate and land use. Similar model-based quantitative reconstruction of plant cover in China has been restricted due to the lack of standardized datasets of existing estimates of relative pollen productivity (RPP). This study presents the first synthesis of all RPP values available to date for 39 major plant taxa from temperate China and proposes standardized RPP datasets that can be used for model-based quantitative reconstructions of past plant cover using fossil pollen records for the region. We review 11 RPP studies in temperate China based on modern pollen and related vegetation data around the pollen samples. The study areas include meadow, steppe and desert vegetation, various woodland types, and cultural landscapes. We evaluate the strategies of each study in terms of selection of study areas and distribution of study sites; pollen- and vegetation-data collection in field; vegetation-data collection from satellite images and vegetation maps; and data analysis. We compare all available RPP estimates, select values based on precise rules and calculate mean RPP estimates. We propose two standardized RPP datasets for 31 (Alt1) and 29 (Alt2) plant taxa. The ranking of mean RPPs (Alt-2) relative to Poaceae (= 1) for eight major taxa is: Artemisia (21) > Pinus (18.4) > Betula (12.5) > Castanea (11.5) > Elaeagnaceae (8.8) > Juglans (7.5) > Compositae (4.5) > Amaranthaceae/Chenopodiaceae (4). We conclude that although RPPs are comparable between Europe and China for some genera and families, they can differ very significantly, e.g., Artemisia, Compositae, and Amaranthaceae/Chenopodiaceae. For some taxa, we present the first RPP estimates e.g. Castanea, Elaeagnaceae, and Juglans. The proposed standardized RPP datasets are essential for model-based reconstructions of past plant cover using fossil pollen records from temperate China.
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| 2. |
- Li, Furong, et al.
(author)
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Modern pollen–€“climate relationships in north Xinjiang, northwestern China : Implications for pollen-based reconstruction of Holocene climate
- 2017
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In: The Holocene. - : Sage Publications. - 0959-6836 .- 1477-0911. ; 27:7, s. 951-966
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Journal article (peer-reviewed)abstract
- Fossil pollen records are widely used to reconstruct past climate. Such reconstructions require that the relationships between pollen assemblages, vegetation, and climate are well understood. These can be studied in present circumstances given we assume that modern vegetation and climate are analogous to past ones. In this study, we analyze pollen–vegetation–climate relationships in the Jungar desert and Altay Mountains, northwestern China, a region for which careful reconstruction of past climate is needed to answer unsolved questions on past climate in an area located at the boundary between two different climate regimes (westerlies and monsoon). We use a dataset of 66 surface pollen samples from forest, meadow, steppe, and desert vegetation and six related climate variables, Tann, TJan, TJul, Pann, PJan, and PJul. Principal components analysis, redundancy analysis, Monte Carlo permutation tests, and variation partitioning are applied to quantify these relationships. We also assess pollen ratios as indices of aridity. We find that (1) Pann is the major climatic factor influencing pollen assemblages, followed by PJul, (2) the two variables are not correlated, and (3) the shared effect of (1) PJan and PJul, (2) PJan and Pann, (3) PJul and Tann, and (4) Tann, TJan, and TJul explains a larger portion of the variation in pollen data than the individual effect of each variable. Therefore, robust pollen–climate transfer functions can be developed for Pann and PJul, and several climate variables treated in combination. Artemisia/Chenopodiaceae is a strong index of aridity and Artemisia/Gramineae might be a useful index of Pann and PJul.
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| 3. |
- Li, Furong, et al.
(author)
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Relative pollen productivity estimates for major plant taxa of cultural landscapes in central eastern China
- 2017
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In: Vegetation History and Archaeobotany. - : Springer. - 0939-6314 .- 1617-6278. ; 26:6, s. 587-605
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Journal article (peer-reviewed)abstract
- In this study we estimate relative pollen productivity (RPP) for plant taxa characteristic of human-induced vegetation in ancient cultural landscapes of the low mountain ranges of Shandong province in eastern temperate China. RPP estimates are required to achieve pollen-based reconstructions of Holocene plant cover using modelling approaches based on Prentice's and Sugita's theoretical background and models (REVEALS and LOVE). Pollen counts in moss samples and vegetation data from 36 sites were used in the Extended R-Value (ERV) model to estimate the relevant source area of pollen (RSAP) of moss polsters and RPP of major plant taxa. The best results were obtained with the ERV sub-model 3 and Prentice's taxon-specific method (using a Gaussian Plume dispersal model) to distance weight vegetation data. RSAP was estimated to 145 m using the maximum likelihood method. RPP was obtained for 18 taxa of which two taxa had unreliable RPP (Amaranthaceae/Chenopodiaceae and Vitex negundo). RPPs for Castanea, Cupressaceae, Robinia/Sophora, Aster/Anthemis-type, Cannabis/Humulus, Caryophyllaceae, Brassicaceae and Galium-type are the first ones for China. Trees, except Robinia/Sophora (RPP = 0.78 +/- 0.03) have larger RPPs than herbs other than Artemisia (RPP = 24.7 +/- 0.36). The RPPs for Quercus, Pinus and Artemisia are comparable with other RPPs obtained in China, the RPPs for Pinus, Quercus, Ulmus, Cyperaceae and Galium-type with the mean RPPs obtained in Europe, and RPP for Cupressaceae with that for Juniperus in Europe. The values for Aster/Anthemis-type, Caryophyllaceae, Asteraceae SF Cichorioideae and Juglans differ from the few RPPs available in China and/or Europe.
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| 4. |
- Li, Jian-De, et al.
(author)
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Co-placement optimization in sensor-reusable cyber-physical digital microfluidic biochips
- 2019
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In: Microelectronics Journal. - : Elsevier. - 0959-8324 .- 0026-2692. ; 83, s. 185-196
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Journal article (peer-reviewed)abstract
- Digital microfluidic biochips (DMFBs) facilitate modern healthcare applications. One of the most important applications is point-of-care (POC) clinical diagnosis which is directly related to human health. However, biochemical experiments are usually error-prone, which makes monitoring intermediate results during bioassay execution be required to ensure the correctness of POC clinical diagnosis. To tackle this problem, cyber-physical digital microfluidic biochips with integrated sensors have been proposed and have attracted attention recently. In order to fully utilize the sensors for detection, the reusability of sensors should be taken into consideration during the module placement stage of cyber-physical DMFBs synthesis flow. Moreover, excessive actuation of electrodes may cause reliability degradation and this issuse should also be taken care of during module placement stage. In order to deal with the aforementioned problems, this paper presents the first co-optimization method for both module and sensor placement. Experimental results show that the proposed method can effectively minimize bioassay completion time while meeting all constraints from sensors and electrodes.
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| 5. |
- Xu, Qinghai, et al.
(author)
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Studies of modern pollen assemblages for pollen dispersal- deposition- preservation process understanding and for pollen-based reconstructions of past vegetation, climate, and human impact : A review based on case studies in China
- 2016
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In: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 149, s. 151-166
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Journal article (peer-reviewed)abstract
- Fossil pollen, as a direct proxy record of past vegetation, and indirect proxy record of past climate, plays an essential role in revealing and reconstructing past vegetation and climate. However, relationships between pollen, vegetation and climate are not linear, hence quantitative reconstructions of past vegetation and climate based on pollen records are not straightforward, and results may be highly contradictory and difficult to interpret. One of the main causes of discrepancies between results has been the lack of comprehensive and systematical studies on modern pollen dispersal and deposition processes, particularly on the quantification of these processes. Based on empirical studies performed in China over the last 30 years, this paper provides the state-of-the-art of the understanding of pollen dispersal and deposition processes in China and the remaining questions to be investigated. We show that major progress has been achieved in the study of modern pollen dispersal and deposition processes, and in the application of models of the pollen-vegetation-climate relationships for quantitative reconstruction of past vegetation and climate. However, several issues are not entirely solved or understood yet, such as how to quantify the reworking and re-deposition of pollen grains in quaternary alluvial sediments, the influence of pollen preservation on pollen assemblages, and human impact on vegetation. Even so, the progress made during the last decades makes it possible to achieve significantly more precise and informative reconstructions of past vegetation, land-use and climate in China than was possible earlier.
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| 6. |
- Zhang, Shengrui, et al.
(author)
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Characteristic pollen source area and vertical pollen dispersal and deposition in a mixed coniferous and deciduous broad-leaved woodland in the Changbai mountains, northeast China.
- 2016
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In: Vegetation History and Archaeobotany. - : Springer Science and Business Media LLC. - 0939-6314 .- 1617-6278. ; 25:1, s. 29-43
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Journal article (peer-reviewed)abstract
- Pollen influx (number of pollen grains cm−2 year−1) can objectively reflect the dispersal and deposition features of pollen within a certain time and space, and is often used as a basis for the quantitative reconstruction of palaeovegetation; however, little is known about the features and mechanisms of vertical dispersal of pollen. Here we present the results from a 5 year (2006–2010) monitoring program using pollen traps placed at different heights from ground level up to 60 m and surface soil samples in a mixed coniferous and deciduous broad-leaved woodland in the Changbai mountains, northeastern China. The pollen percentages and pollen influx from the traps have very similar characteristics to the highest values for Betula,Fraxinus, Quercus and Pinus, among the tree taxa and Artemisia, Chenopodiaceae and Asteraceae among the herb taxa. Pollen influx values vary significantly with height and show major differences between three distinct layers, above-canopy (≥32 m), within the trunk layer (8 ≤ 32 m) and on the ground (0 m). These differences in pollen influx are explained by differences in (i) the air flows in each of these layers and (ii) the fall speed of pollen of the various taxa. We found that the pollen recorded on the ground surface is a good representation of the major part of the pollen transported in the trunk space of the woodland. Comparison of the pollen influx values with the theoretical, calculated “characteristic pollen source area” (CPSA) of 12 selected taxa indicates that the pollen deposited on the ground surface of the woodland is a fair representation with 85–90 % of the total pollen deposited at a wind speed of 2.4 m s−1 coming from within ca. 1–5 km for Pinus and Quercus, ca. 5–10 km for Ulmus, Tilia, Oleaceae and Betula, ca. 20–40 km for Fraxinus, Poaceae, Chenopodiaceae, Populus andSalix, and ca. 30–60 km for Artemisia; it is also a good representation with 90–98 % of the total pollen deposited coming from within 60 km at a wind speed of 2.4 m s−1, or 100 km at a wind speed: 6 m s−1, for the 12 selected taxa used in the CPSA calculation. Furthermore, comparison with the vegetation map of the area around the sampling site shows that the pollen deposited on the ground represents all plant communities which grow in the study area within 70 km radius of the sampling site. In this study, the pollen percentages obtained from the soil surface samples are significantly biased towards pollen taxa with good preservation due to thick and robust pollen walls. Therefore, if mosses are available instead, soil samples should be avoided for pollen studies, in particular for the study of pollen-vegetation relationships, the estimation of pollen productivities and quantitative reconstruction of past vegetation. The results also indicate that the existing model of pollen dispersal and deposition, Prentice’s model, provides a fair description of the actual pollen dispersal and deposition in this kind of woodland, which suggests that the application of the landscape reconstruction algorithm would be relevant for reconstruction of this type of woodland in the past.
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| 7. |
- Abdalla, H., et al.
(author)
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Gamma-ray blazar spectra with HESS II mono analysis : The case of PKS2155-304 and PG1553+113
- 2017
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 600
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Journal article (peer-reviewed)abstract
- Context. The addition of a 28 m Cherenkov telescope (CT5) to the H.E.S.S. array extended the experiment's sensitivity to lower energies. The lowest energy threshold is obtained using monoscopic analysis of data taken with CT5, providing access to gamma-ray energies below 100 GeV for small zenith angle observations. Such an extension of the instrument's energy range is particularly beneficial for studies of active galactic nuclei with soft spectra, as expected for those at a redshift >= 0.5. The high-frequency peaked BL Lac objects PKS 2155-304 (z = 0.116) and PG 1553 + 113 (0.43 < z < 0.58) are among the brightest objects in the gamma-ray sky, both showing clear signatures of gamma-ray absorption at E > 100 GeV interpreted as being due to interactions with the extragalactic background light (EBL). Aims. The aims of this work are twofold: to demonstrate the monoscopic analysis of CT5 data with a low energy threshold, and to obtain accurate measurements of the spectral energy distributions (SED) of PKS 2155-304 and PG 1553 + 113 near their SED peaks at energies approximate to 100 GeV. Methods. Multiple observational campaigns of PKS 2155 304 and PG 1553 + 113 were conducted during 2013 and 2014 using the full H.E.S.S. II instrument (CT1-5). A monoscopic analysis of the data taken with the new CT5 telescope was developed along with an investigation into the systematic uncertainties on the spectral parameters which are derived from this analysis. Results. Using the data from CT5, the energy spectra of PKS 2155 304 and PG 1553 + 113 were reconstructed down to conservative threshold energies of 80 GeV for PKS 2155 304, which transits near zenith, and 110 GeV for the more northern PG 1553 + 113. The measured spectra, well fitted in both cases by a log-parabola spectral model ( with a 5.0 similar to statistical preference for non-zero curvature for PKS 2155 304 and 4.5 sigma for PG 1553+113), were found consistent with spectra derived from contemporaneous Fermi-LAT data, indicating a sharp break in the observed spectra of both sources at E approximate to 100 GeV. When corrected for EBL absorption, the intrinsic H.E.S.S. II mono and Fermi-LAT spectrum of PKS 2155 304 was found to show significant curvature. For PG 1553+113, however, no significant detection of curvature in the intrinsic spectrum could be found within statistical and systematic uncertainties.
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| 8. |
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| 9. |
- Beijer, Ulla, et al.
(author)
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Are clear boundaries a prerequisite for well-functioning collaboration in home health care? : A mixed methods study
- 2018
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In: Scandinavian Journal of Caring Sciences. - : Nordic College of Caring Science. - 0283-9318 .- 1471-6712. ; 32:1, s. 128-137
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Journal article (peer-reviewed)abstract
- Aim: The aim of this study was to examine whether professional collaboration in home health care is associated with clear boundaries between principals' areas of responsibility and the professions areas of responsibility, respectively.Methods: Data were derived from a web-based survey that was carried out in one county in the middle of Sweden during spring 2013. Participants were health professionals and managers from the county council and from all the municipalities in the county. Both structured and open-ended questions were utilised. A total of 421 individuals (90% women) answered the structured questions, and 91 individuals (22% of the 421) answered the open-ended questions. Quantitative data were analysed with descriptive statistics methods, tests of independence and of correlation strength. Qualitative data were analysed with content analysis.Results: The results from the structured questions showed that well-functioning collaboration was associated with clear boundaries between principals in the county overall, and for respondents in two of three parts of the county. Association between clear boundaries between professions and well-functioning collaboration was found in the county overall among the municipality population. However, in one part of the county, we did not find any correlations between well-functioning collaboration and clear boundaries between professions or principals, with the exception of home help services. The analysis of the open questions gave similar results as the quantitative analysis, illustrated within three themes: The significance of concepts, trust and interdependence, and collaboration as a means for well-being.Conclusion: The results indicate that, recently after an organisational change, clear boundaries between the principals' areas of responsibility and professions' area of responsibility respectively are necessary for effective cooperation between professionals. If the organisation and professionals have previous positive experience of colocated activities, clear boundaries do not share the same importance.
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| 10. |
- Bergman Nordgren, Lise, et al.
(author)
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Polariserad debatt om riktlinjer skymmer viktiga frågor
- 2018
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In: Läkartidningen. - 0023-7205 .- 1652-7518. ; 115:37, s. 1372-1372
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Journal article (pop. science, debate, etc.)abstract
- Debatten om Socialstyrelsens nya riktlinjer för ångest och depression har varit polariserad och inte konstruktiv. Diskussionen bör inte handla om PDT eller KBT utan om evidensbaserade metoder och kompetensbrist.
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