| 1. |
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| 2. |
- Badr, Hussein O., et al.
(författare)
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Bottom-up, scalable synthesis of anatase nanofilament-based two-dimensional titanium carbo-oxide flakes
- 2022
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Ingår i: Materials Today. - : ELSEVIER SCI LTD. - 1369-7021 .- 1873-4103. ; 54
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Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional (2D) materials offer advantages that their 3D counterparts do not. The conventional method for the bulk synthesis of 2D materials has predominantly been through etching layered solids. Herein, we convert - through a bottom-up approach - 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides into 2D flakes by immersing them in a tetramethylammonium hydroxide solution at temperatures in the 25-85 degrees C range. Based on X-ray diffraction, density functional theory, X-ray photoelectron, electron energy loss, Raman, X-ray absorption near edge structure spectroscopies, transmission and scanning electron microscope images and selected area diffraction, we conclude that the resulting flakes are carbon containing anatase-based layers that are, in turn, comprised of approximate to 6 x 10 angstrom(2) nanofilaments in cross-section some of which are few microns long. Electrodes made from some of these films performed well in lithium-ion and lithium-sulphur systems. These materials also reduce the viability of cancer cells thus showing potential in biomedical applications. Synthesizing 2D materials, at near ambient conditions, with non-layered, inexpensive, green precursors (e.g., TiC) is paradigm shifting and will undoubtedly open new and exciting avenues of research and applications.
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| 3. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 4. |
- Qian, Jy, et al.
(författare)
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Heat transfer analysis on dimple geometries and arrangements in dimple jacketed heat exchanger
- 2019
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Ingår i: International Journal of Numerical Methods for Heat and Fluid Flow. - 0961-5539. ; 29:8, s. 2775-2791
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The purpose of this paper is to study the effects of dimple geometries and arrangements on the heat transfer enhancement in a dimple jacketed heat exchanger. Design/methodology/approach: For the purpose of this paper, with the experimental validated numerical model, this paper carries out numerical simulations of both single dimples with different geometries and the whole dimple jacketed heat exchanger with different dimple arrangements. For a single dimple, its secondary vortex flow, temperature differences and the pressure drop performance for different geometries are analyzed. For the whole dimple jacketed heat exchanger, the heat transfer and pressure drop performances are investigated by comparing the no dimple, triangular and rectangular dimple arrangements. Findings: Results show that dimples can improve the heat transfer efficiency compared with conventional jacketed heat exchanger, and specific geometries and arrangement of dimples for better heat transfer performance are figured out. Originality/value: This paper considers both dimple geometries and arrangements, which can be useful for further applications in specific integrated devices or similar applications.
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| 5. |
- Yao, Tandong, et al.
(författare)
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Recent Third Pole’s rapid warming accompanies cryospheric melt and water cycle intensification and interactions between monsoon and environment: multi-disciplinary approach with observation, modeling and analysis
- 2019
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Ingår i: Bulletin of The American Meteorological Society. - 0003-0007 .- 1520-0477. ; :March, s. 423-444
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Tidskriftsartikel (refereegranskat)abstract
- The Third Pole (TP) is experiencing rapid warming and is currently in its warmest period in the past 2,000 years. This paper reviews the latest development in multidisciplinary TP research associated with this warming. The rapid warming facilitates intense and broad glacier melt over most of the TP, although some glaciers in the northwest are advancing. By heating the atmosphere and reducing snow/ice albedo, aerosols also contribute to the glaciers melting. Glacier melt is accompanied by lake expansion and intensification of the water cycle over the TP. Precipitation has increased over the eastern and northwestern TP. Meanwhile, the TP is greening and most regions are experiencing advancing phenological trends, although over the southwest there is a spring phenological delay mainly in response to the recent decline in spring precipitation. Atmospheric and terrestrial thermal and dynamical processes over the TP affect the Asian monsoon at different scales. Recent evidence indicates substantial roles that mesoscale convective systems play in the TP’s precipitation as well as an association between soil moisture anomalies in the TP and the Indian monsoon. Moreover, an increase in geohazard events has been associated with recent environmental changes, some of which have had catastrophic consequences caused by glacial lake outbursts and landslides. Active debris flows are growing in both frequency of occurrences and spatial scale. Meanwhile, new types of disasters, such as the twin ice avalanches in Ali in 2016, are now appearing in the region. Adaptation and mitigation measures should be taken to help societies’ preparation for future environmental challenges. Some key issues for future TP studies are also discussed.
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| 6. |
- Bogg, Lennart, et al.
(författare)
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Dramatic Increase of Cesarean Deliveries in the Midst of Health Reforms in Rural China
- 2010
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Ingår i: Social Science and Medicine. - : Elsevier. - 0277-9536 .- 1873-5347. ; 70:10, s. 1544-1549
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Tidskriftsartikel (refereegranskat)abstract
- Cesarean delivery (CD) rates were until recently low in rural China where the population lacked healthinsurance. In July 2003 the New Cooperative Medical Scheme (NCMS) was introduced. We report findingsfrom a health systems study carried out in the EC-funded project ‘‘Structural hinders to andpromoters of good maternal care in rural China’’ in central and western China. The purpose was toanalyze how CD rates changed with the increased level of funding of the NCMS.The research design was a natural experiment. Quantitative demographic, administrative and accountsdata for 2001–2007 were collected in five counties from the county public health bureaux, the countyNCMS offices, the county statistical offices and the Maternal and Child Health (MCH) hospitals, usinga structured data collection form. We found that the CD rates increased in four of the five counties in theperiod 2004–2007 by 36%, 53%, 61% and 131% respectively. In the fifth county the CD rate remained highat 60%. The revenue from CD made up 72–85% of total delivery fee revenue. CD fee revenue increased by97%, 239% and 408% in the three counties with available data; a higher increase than in general healthcare revenue. Our conclusion is that the design of NCMS, the provider payment systems, and therevenue-related bonus systems for doctors need to be studied to rein in the unhealthy increases in ruralCD rates.
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| 7. |
- Claussnitzer, Melina, et al.
(författare)
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Leveraging cross-species transcription factor binding site patterns: from diabetes risk Loci to disease mechanisms.
- 2014
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Ingår i: Cell. - : Elsevier BV. - 1097-4172 .- 0092-8674. ; 156:1-2, s. 343-358
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies have revealed numerous risk loci associated with diverse diseases. However, identification of disease-causing variants within association loci remains a major challenge. Divergence in gene expression due to cis-regulatory variants in noncoding regions is central to disease susceptibility. We show that integrative computational analysis of phylogenetic conservation with a complexity assessment of co-occurring transcription factor binding sites (TFBS) can identify cis-regulatory variants and elucidate their mechanistic role in disease. Analysis of established type 2 diabetes risk loci revealed a striking clustering of distinct homeobox TFBS. We identified the PRRX1 homeobox factor as a repressor of PPARG2 expression in adipose cells and demonstrate its adverse effect on lipid metabolism and systemic insulin sensitivity, dependent on the rs4684847 risk allele that triggers PRRX1 binding. Thus, cross-species conservation analysis at the level of co-occurring TFBS provides a valuable contribution to the translation of genetic association signals to disease-related molecular mechanisms.
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| 8. |
- Fachrizal, Reza, 1993-, et al.
(författare)
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Urban-scale energy matching optimization with smart EV charging and V2G in a net-zero energy city powered by wind and solar energy
- 2024
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Ingår i: eTransporation. - : Elsevier. - 2590-1168. ; 20
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Tidskriftsartikel (refereegranskat)abstract
- Renewable energy sources (RES) and electric vehicles (EVs) are two promising technologies that are widely recognized as key components for achieving sustainable cities. However, intermittent RES generation and increased peak load due to EV charging can pose technical challenges for the power systems. Many studies have shown that improved load matching through energy system optimization can minimize these challenges. This paper assesses the optimal urban-scale energy matching potentials in a net-zero energy city powered by wind and solar energy, considering three EV charging scenarios: opportunistic charging, smart charging, and vehicle-to-grid (V2G). This paper takes a city on the west coast of Sweden as a case study. The smart charging and V2G schemes in this study aim to minimize the mismatch between generation and load and are formulated as quadratic programming problems. Results show that the optimal load matching performance is achieved in a net-zero energy city with the V2G scheme and a wind-PV electricity production share of 70:30. The load matching performance is increased from 68% in the opportunistic charging scenario to 73% in the smart charging scenario and to 84% in the V2G scenario. It is also shown that a 2.4 GWh EV battery participating in the V2G scheme equals 1.4 GWh stationary energy storage in improving urban-scale load matching performance. The findings in this paper indicate a high potential from EV flexibility in improving urban energy system performance.
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| 9. |
- Gao, Yun, et al.
(författare)
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Region separation type bio-photoelectrode based all-solid-state self-powered aptasensor for ochratoxin A and aflatoxin B1 detection
- 2022
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Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 364
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Tidskriftsartikel (refereegranskat)abstract
- Ochratoxin A (OTA) and Aflatoxin B1 (AFB1) are two highly toxic and naturally coexistence mycotoxins, which have posed a serious threat to food safety. The coexistence of these two mycotoxins can produce significant synergistic effects, so it is necessary to establish an effective analytical method. In this work, a dual biophotoelectrode based all-solid-state multiplexed self-powered aptasensor was realized for high-throughput analysis of OTA and AFB1. There was a large Fermi level difference between photoanode and photocathode, which ensured the light assisted self-driving of the system. Due to the regional immobilization of aptamers, it could save the dosage of recognition elements, reduce the preparation cost and simplify the operation procedure. Meanwhile, construction strategy of spatial separation could effectively eliminate the overlapping signals and cross interference between targets, achieving the results more accurate and the calculation more convenient. The constructed aptasensor realized OTA and AFB1 detection in corn samples with practicality, good stability, antiinterference ability and repeatability. Therefore, this work not only achieved the high-throughput analysis of mycotoxins, but also provided a new perspective for the construction of all-solid-state multiplexed self-powered sensor.
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| 10. |
- He, Yafang, et al.
(författare)
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Metabolomic Changes Upon Conjugated Linoleic Acid Supplementation and Predictions of Body Composition Responsiveness
- 2022
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 107:9, s. 2606-2615
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Tidskriftsartikel (refereegranskat)abstract
- Context Conjugated linoleic acid (CLA) may optimize body composition, yet mechanisms underlining its benefits are not clear in humans. Objective We aimed to reveal the CLA-induced changes in the plasma metabolome associated with body composition improvement and the predictive performance of baseline metabolome on intervention responsiveness. Methods Plasma metabolome from overnight fasted samples at pre- and post-intervention of 65 participants in a 12-week randomized, placebo-controlled trial (3.2 g/day CLA vs 3.2 g/day sunflower oil) were analyzed using untargeted LC-MS metabolomics. Mixed linear model and machine learning were applied to assess differential metabolites between treatments, and to identify optimal panel (based on baseline conventional variables vs metabolites) predicting responders of CLA-derived body composition improvement (increased muscle variables or decreased adiposity variables) based on dual-energy x-ray absorptiometry. Results Compared with placebo, CLA altered 57 metabolites (P
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| 11. |
- Ma, Tao, et al.
(författare)
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Ancient polymorphisms and divergence hitchhiking contribute to genomic islands of divergence within a poplar species complex
- 2018
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : NATL ACAD SCIENCES. - 0027-8424 .- 1091-6490. ; 115:2, s. E236-E243
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Tidskriftsartikel (refereegranskat)abstract
- How genome divergence eventually leads to speciation is a topic of prime evolutionary interest. Genomic islands of elevated divergence are frequently reported between diverging lineages, and their size is expected to increase with time and gene flow under the speciation-with-gene-flow model. However, such islands can also result from divergent sorting of ancient polymorphisms, recent ecological selection regardless of gene flow, and/or recurrent background selection and selective sweeps in low-recombination regions. It is challenging to disentangle these nonexclusive alternatives, but here we attempt to do this in an analysis of what drove genomic divergence between four lineages comprising a species complex of desert poplar trees. Within this complex we found that two morphologically delimited species, Populus euphratica and Populus pruinosa, were paraphyletic while the four lineages exhibited contrasting levels of gene flow and divergence times, providing a good system for testing hypotheses on the origin of divergence islands. We show that the size and number of genomic islands that distinguish lineages are not associated with either rate of recent gene flow or time of divergence. Instead, they are most likely derived from divergent sorting of ancient polymorphisms and divergence hitchhiking. We found that highly diverged genes under lineage-specific selection and putatively involved in ecological and morphological divergence occur both within and outside these islands. Our results highlight the need to incorporate demography, absolute divergence measurement, and gene flow rate to explain the formation of genomic islands and to identify potential genomic regions involved in speciation.
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| 12. |
- Ma, Tao, et al.
(författare)
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Genomic insights into salt adaptation in a desert poplar
- 2013
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 4, s. 2797-
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Tidskriftsartikel (refereegranskat)abstract
- Despite the high economic and ecological importance of forests, our knowledge of the genomic evolution of trees under salt stress remains very limited. Here we report the genome sequence of the desert poplar, Populus euphratica, which exhibits high tolerance to salt stress. Its genome is very similar and collinear to that of the closely related mesophytic congener, P. trichocarpa. However, we find that several gene families likely to be involved in tolerance to salt stress contain significantly more gene copies within the P. euphratica lineage. Furthermore, genes showing evidence of positive selection are significantly enriched in functional categories related to salt stress. Some of these genes, and others within the same categories, are significantly upregulated under salt stress relative to their expression in another salt-sensitive poplar. Our results provide an important background for understanding tree adaptation to salt stress and facilitating the genetic improvement of cultivated poplars for saline soils.
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| 13. |
- Qian, Kun, et al.
(författare)
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An eye tracking based virtual reality system for use inside magnetic resonance imaging systems
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Patients undergoing Magnetic Resonance Imaging (MRI) often experience anxiety and sometimes distress prior to and during scanning. Here a full MRI compatible virtual reality (VR) system is described and tested with the aim of creating a radically different experience. Potential benefits could accrue from the strong sense of immersion that can be created with VR, which could create sense experiences designed to avoid the perception of being enclosed and could also provide new modes of diversion and interaction that could make even lengthy MRI examinations much less challenging. Most current VR systems rely on head mounted displays combined with head motion tracking to achieve and maintain a visceral sense of a tangible virtual world, but this technology and approach encourages physical motion, which would be unacceptable and could be physically incompatible for MRI. The proposed VR system uses gaze tracking to control and interact with a virtual world. MRI compatible cameras are used to allow real time eye tracking and robust gaze tracking is achieved through an adaptive calibration strategy in which each successive VR interaction initiated by the subject updates the gaze estimation model. A dedicated VR framework has been developed including a rich virtual world and gaze-controlled game content. To aid in achieving immersive experiences physical sensations, including noise, vibration and proprioception associated with patient table movements, have been made congruent with the presented virtual scene. A live video link allows subject-carer interaction, projecting a supportive presence into the virtual world.
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| 14. |
- Qian, Kun, et al.
(författare)
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Large-scale EV charging scheduling considering on-site PV generation by combining an aggregated model and sorting-based methods
- 2024
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Ingår i: Sustainable cities and society. - : Elsevier. - 2210-6707. ; 107
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Tidskriftsartikel (refereegranskat)abstract
- Large-scale electric vehicle (EV) charging scheduling is highly relevant for the growing number of EVs, while it can be complex to solve. A few existing studies have applied a two-stage scheduling approach to reduce computation time. The first stage approximates the optimal overall load, and the second prioritizes the charging. This work also attempts to apply such an approach for large-scale EV charging considering on-site photovoltaic (PV) generation at a workplace. However, validation and analysis are missing to address whether and why the two-stage approach is suitable. Besides, the existing studies lack exploring different methods to prioritize charging. This work investigates the two-stage approach. Simulation results show the non-uniqueness of the optimal solution from the optimal individual model, and guided by the optimal overall load, sorting-based methods can often lead to an optimal solution, while non-optimal solutions only cause decreases in the load-matching performance with a median value of less than 1%. The aggregated model usually cannot achieve the optimal overall load due to model simplifications. However, further applying sorting-based methods will reduce the differences between the final and the optimal overall load. Thus, the two-stage approach is suitable for this study, and further simulations show that it can achieve almost the optimal annual performance with around 1/57 of the computation time. Furthermore, this study explores different methods to prioritize charging. Simulation results show no difference in performance, while the Least Laxity First method leads to around 54.6% more switching.
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| 15. |
- Qian, Kun, et al.
(författare)
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The Impact of Considering State of Charge Dependent Maximum Charging Powers on the Optimal Electric Vehicle Charging Scheduling
- 2023
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Ingår i: IEEE Transactions on Transportation Electrification. - : Institute of Electrical and Electronics Engineers (IEEE). - 2332-7782 .- 2372-2088. ; 9:3, s. 4517-4530
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Tidskriftsartikel (refereegranskat)abstract
- Intelligent charging solutions facilitate mobility electrification. Mathematically, electric vehicle (EV) charging scheduling formulations are constrained optimization problems. Therefore, accurate constraint modeling is theoretically and practically relevant for scheduling. However, the current scheduling literature lacks an accurate problem formulation, including the joint modeling of the nonlinear battery charging profile and minimum charging power constraints. The minimum charging power constraint prevents allocating inexecutable charging profiles. Furthermore, if the problem formulation does not consider the battery charging profile, the scheduling execution may deviate from the allocated charging profile. An insignificant deviation indicates that simplified modeling is acceptable. After providing the problem formulation targeting the maximum possible vehicle battery state of charge (SoC) on departure, the numerical assessment shows how the constraint consideration impacts the scheduling performance in typical charging scenarios (weekday workplace and weekend public charging where the grid supplies up to forty vehicles). The simulation results show that the nonlinear battery charging constraint is practically negligible: For many connected EVs, the grid limit frequently overrules that constraint. The resulting difference between the final mean SoCs using and not using accurate modeling does not exceed 0.2%. Consequently, the results justify simplified modeling (excluding the nonlinear charging profile) for similar scenarios in future contributions.
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| 16. |
- Qian, Kun, et al.
(författare)
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Validating and Improving an Aggregated EV Model for Energy Systems Evaluation
- 2023
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Ingår i: 2023 11th International Conference on Smart Grid, icSmartGrid. - Paris : IEEE. - 9798350310665 - 9798350310672
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Konferensbidrag (refereegranskat)abstract
- With the trend in transportation electrification, electric vehicle (EV) charging/discharging scheduling has become an area of concern. Scheduling can help manage EV charging/discharging activities. Besides, it is also valuable for energy systems evaluation, in which case modeling the individual EV has high complexity and requires a long computation time due to too many EVs. The aggregated model significantly reduces computation time but may sacrifice accuracy. This work investigates the trade-off between accuracy and computational time when designing intelligent EV charging/discharging scheduling by comparing the individual and aggregated models. This work first provides a detailed problem formulation. The simulation results show that the aggregated model can achieve similar energy system performance estimations from the energy-matching perspective compared to the individual model, given that the system allows vehicle-to-grid (V2G). Otherwise, the aggregated model will overestimate the performance. Thus, this work, in the meantime, proposes an extra constraint to avoid such overestimation when V2G is not allowed. Given the validated accuracy of the aggregated model and its advantage of low complexity and computation time, the aggregated model is more suitable for assessing large (e.g., city-level) energy systems.
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| 17. |
- Qian, Li-Bing, et al.
(författare)
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Transmission of electrons through the conical glass capillary with the grounded conducting outer surface
- 2017
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Ingår i: Wuli xuebao. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 66:12
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Tidskriftsartikel (refereegranskat)abstract
- The transmission of 1.5 keV-electrons through a conical glass capillary is reported. This study aims to understand the so-called guiding effect for the negatively charged particles (e.g. electrons). The guiding mechanism is understood quite well with positively charged particles in particular highly charged ions, but not clear with electrons, i. e., even the basic scheme mediated by the existence of negative charge patches to guide the electrons is still somewhat controversial.. The study of the charging-up dynamics causing the electrons transport inside the capillary will shed light on this issue. In order to perform this, a data acquisition system has been setup to follow the time evolution of the two-dimensional angular distribution of the transmitted electrons. The electrons are detected by the multi-channel plate (MCP) detector with a phosphor screen. The image from the phosphor screen is recorded by a charge-coupled device camera. The timing signals for the detected events are extracted from the back stack of the MCP detector and recorded by the data acquisition system, synchronized with the acquired images. The electron beam has a size of 0.5 mm x 0.5 mm and a divergence of less than 0.35.. The inner diameter of the straight part of the capillary is 1.2 mm and the exit diameter is 225 mu m. A small conducting aperture of 0.3 mm in diameter is placed at the entrance of the capillary. Two-dimensional angular distribution of the transmitted electrons through conical glass capillary and its time evolution are measured. The results show that the transmission rate decreases and reaches to a constant value for the completely discharged glass capillary with time going by. The centroid of the angular distribution moves to an asymptotic value while the width remains unchanged. These transmission characteristics are different from those indicated in our previous work (2016 Acta Phys: Si n: 65 204103). The difference originates from the different manipulations of the capillary outer surface. A conducting layer is coated on the outer surface of the capillary and grounded in this work. This isolates various discharge/charge channels and forms a new stable discharge channel. The transmission rate as a function of the tilt angle shows that the allowed transmission occurs at the tilt angle limited by the geometrical factors, i. e., the geometrical opening angle given by the aspect ratio as well as the beam divergence. The transmission characteristics suggest that most likely there are formed no negative patches to facilitate the electron transmission through the glass capillary at this selected beam energy. It is different from that of highly charged ions, where the formation of the charge patches prohibits the close collisions between the following ions and guides them out of the capillary.
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| 18. |
- Qian, Xukun, et al.
(författare)
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Structure stability of metal-organic framework MIL-53 (Al) in aqueous solutions
- 2013
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Ingår i: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 38:36, s. 16710-16715
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Tidskriftsartikel (refereegranskat)abstract
- The structural stability of MIL-53 (Al) in different pH aqueous solutions from room temperature to 100 degrees C has been investigated. Experimental results show MIL-53 (Al) is stable and highly resistant to hydrolysis in neutral and acidic solutions. It can retain its crystallinity and permanent porosity without structural collapse. The good structure stability of MIL-53 (Al) to aqueous solutions is quite unusual among the MOFs. The nitrogen adsorption for the soaked frameworks show a typical type I isotherm. In basic aqueous solution, MIL-53 (Al) undergoes structure transformation.
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| 19. |
- Qin, Shun-Shun, et al.
(författare)
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Dual-functional ionic porous organic framework for palladium scavenging and heterogeneous catalysis
- 2021
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Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 13:7, s. 3967-3973
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Tidskriftsartikel (refereegranskat)abstract
- Porous organic frameworks (POFs) with predesigned structures and tunable porosities have been widely studied in adsorption and heterogeneous catalysis. Introducing ionic structure into the framework endows POFs with new functionalities that may extend their applications. Here, we report new applications for a guanidinium-based ionic POF (IPOF-Cl) in palladium scavenging and heterogeneous catalysis. Due to the ionic framework and the porous structure, the IPOF-Cl displays fast adsorption kinetics and high adsorption capacities (up to 754 mg g−1) of Na2PdCl4 in aqueous solutions via a chemisorption (ion exchange) process. Significantly, it shows excellent scavenging activity towards trace amount of [PdCl4]2− in aqueous solution. More importantly, the loaded [PdCl4]2− species on the IPOF substrate are further reduced into ultrafine Pd nanoparticles with size of ∼2–5 nm. The obtained IPOF-Pd(0) nanocomposite containing uniformly distributed Pd nanoparticles and hierarchical porous structure demonstrates high activity in catalyzing a range of Suzuki coupling reactions. This study provides new routes for the development of ionic porous organic materials for applications in metal scavenging and catalysis.
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| 20. |
- Sampson, Joshua N., et al.
(författare)
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Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for 13 Cancer Types
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 107:12
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Tidskriftsartikel (refereegranskat)abstract
- Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, h(l)(2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (rho = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (rho = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (rho = 0.51, SE = 0.18), and bladder and lung (rho = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.
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| 21. |
- Shao, Wen-Ze, et al.
(författare)
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DeblurGAN plus : Revisiting blind motion deblurring using conditional adversarial networks
- 2020
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Ingår i: Signal Processing. - : ELSEVIER. - 0165-1684 .- 1872-7557. ; 168
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Tidskriftsartikel (refereegranskat)abstract
- This work studies dynamic scene deblurring (DSD) of a single photograph, mainly motivated by the very recent DeblurGAN method. It is discovered that training the generator alone of DeblurGAN will result in both regular checkerboard effects and irregular block color excursions unexpectedly. In this paper, two aspects of endeavors are made for a more effective and robust adversarial learning approach to DSD. On the one hand, a kind of opposite-channel -based discriminative priors is developed, improving the deblurring performance of DeblurGAN without additional computational burden in the testing phase. On the other hand, a computationally more efficient while architecturally more robust auto -encoder is developed as a substitute of the original generator in DeblurGAN, promoting DeblurGAN to a new state-of-the-art method for DSD. For brevity, the proposed approach is dubbed as DeblurGAN+. Experimental results on the benchmark GoPro dataset validate that DeblurGAN+ achieves more than 1.5 dB improvement than DeblurGAN in terms of PSNR as trained utilizing the same amount of data. More importantly, the results on realistic non -uniform blurred images demonstrate that DeblurGAN+ is really more effective than DeblurGAN as well as most of variational model-based methods in terms of both blur removal and detail recovery.
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| 22. |
- Shao, Wen-Ze, et al.
(författare)
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On potentials of regularized Wasserstein generative adversarial networks for realistic hallucination of tiny faces
- 2019
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Ingår i: Neurocomputing. - : ELSEVIER. - 0925-2312 .- 1872-8286. ; 364, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Super-resolution of facial images, a.k.a. face hallucination, has been intensively studied in the past decades due to the increasingly emerging analysis demands in video surveillance, e.g., face detection, verification, identification. However, the actual performance of most previous hallucination approaches will drop dramatically when a very low-res tiny face is provided, due to the challenging multimodality of the problem as well as lack of an informative prior as a strong semantic guidance. Inspired by the latest progress in deep unsupervised learning, this paper focuses on tiny faces of size 16 x 16 pixels, hallucinating them to their 8 x upsampling versions by exploring the potentials of Wasserstein generative adversarial networks (WGAN). Besides a pixel-wise L2 regularization term imposed to the generative model, it is found that our advocated autoencoding generator with both residual and skip connections is a critical component for WGAN representing the facial contour and semantic content to a reasonable precision. With the additional Lipschitz penalty and architectural considerations for the critic in WGAN, the proposed approach finally achieves state-of-the-art hallucination performance in terms of both visual perception and objective assessment. The cropped CelebA face dataset is primarily used to aid the tuning and analysis of the new method, termed as tfh-WGAN. Experimental results demonstrate that the proposed approach not only achieves realistic hallucination of tiny faces, but also adapts to pose, expression, illuminance and occluded variations to a great degree.
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| 23. |
- Wang, Ze-Kun, et al.
(författare)
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Assembly of Discrete Chalcogenolate Clusters into a One-Dimensional Coordination Polymer with Enhanced Photocatalytic Activity and Stability
- 2020
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 59:4, s. 2121-2126
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Tidskriftsartikel (refereegranskat)abstract
- Interlinking discrete supertetrahedral chalcogenolate clusters with conjugated bipyridine linkers form a one-dimensional coordination polymer, [Cd6Ag4(SPh)16(DMF)(H2O)(bpe)]n (1a), displaying a broader visible-light absorption and a narrower band gap than those of the discrete cluster. More importantly, the coordination polymer demonstrates enhanced activity and stability for the photocatalytic degradation of organic dye in water.
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| 24. |
- Wu, Renbing, et al.
(författare)
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Pt nanodendrites anchored on bamboo-shaped carbon nanofiber arrays as highly efficient electrocatalyst for oxygen reduction reaction
- 2013
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Ingår i: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 38:36, s. 16677-16684
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Tidskriftsartikel (refereegranskat)abstract
- In order to improve the Pt utilization and enhance their catalytic performance in fuel cells, a novel composite electrode composed of single-crystalline Pt nanodendrites and support constructed by bamboo-shaped carbon nanofiber arrays (CNFAs) on carbon paper, is reported. This electrode is designed by growing vertically CNFAs on carbon paper via plasma enhanced chemical vapor deposition, followed by the direct synthesis of Pt nanodendrites using a simple surfactant-free aqueous solution method. Electron microscopy studies reveal that the Pt nanodendrites are uniformly high dispersed and anchored on the surface of CNFAs. Electrochemical measurements demonstrate that the resultant electrode exhibits higher electrocatalytic activity and stability for oxygen reduction reaction than commercial Pt/C catalyst, suggesting its potential application in fuel cells.
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| 25. |
- Xia, Jianyang, et al.
(författare)
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Terrestrial ecosystem model performance in simulating productivity and its vulnerability to climate change in the northern permafrost region
- 2017
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Ingår i: Journal of Geophysical Research - Biogeosciences. - 2169-8953. ; 122:2, s. 430-446
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Tidskriftsartikel (refereegranskat)abstract
- Realistic projection of future climate-carbon (C) cycle feedbacks requires better understanding and an improved representation of the C cycle in permafrost regions in the current generation of Earth system models. Here we evaluated 10 terrestrial ecosystem models for their estimates of net primary productivity (NPP) and responses to historical climate change in permafrost regions in the Northern Hemisphere. In comparison with the satellite estimate from the Moderate Resolution Imaging Spectroradiometer (MODIS; 246±6gCm-2yr-1), most models produced higher NPP (309±12gCm-2yr-1) over the permafrost region during 2000-2009. By comparing the simulated gross primary productivity (GPP) with a flux tower-based database, we found that although mean GPP among the models was only overestimated by 10% over 1982-2009, there was a twofold discrepancy among models (380 to 800gCm-2yr-1), which mainly resulted from differences in simulated maximum monthly GPP (GPPmax). Most models overestimated C use efficiency (CUE) as compared to observations at both regional and site levels. Further analysis shows that model variability of GPP and CUE are nonlinearly correlated to variability in specific leaf area and the maximum rate of carboxylation by the enzyme Rubisco at 25°C (Vcmax_25), respectively. The models also varied in their sensitivities of NPP, GPP, and CUE to historical changes in climate and atmospheric CO2 concentration. These results indicate that model predictive ability of the C cycle in permafrost regions can be improved by better representation of the processes controlling CUE and GPPmax as well as their sensitivity to climate change.
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| 26. |
- Yan, Tao, et al.
(författare)
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Habitual intakes of sugar-sweetened beverages associated with gut microbiota-related metabolites and metabolic health outcomes in young Chinese adults
- 2023
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Ingår i: Nutrition, Metabolism and Cardiovascular Diseases. - : Elsevier BV. - 0939-4753 .- 1590-3729. ; 33:2, s. 359-368
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Tidskriftsartikel (refereegranskat)abstract
- Background and aims: Reducing consumption of sugar-sweetened beverages (SSBs) is a global public health priority because of their limited nutritional value and associations with increased risk of obesity and metabolic diseases. Gut microbiota-related metabolites emerged as quintessential effectors that may mediate impacts of dietary exposures on the modulation of host commensal microbiome and physiological status. Methods and results: This study assessed the associations among SSBs, circulating microbial metabolites, and gut microbiota–host co-metabolites, as well as metabolic health outcomes in young Chinese adults (n = 86), from the Carbohydrate Alternatives and Metabolic Phenotypes study in Shaanxi Province. Five principal component analysis-derived beverage drinking patterns were determined on self-reported SSB intakes, which were to a varying degree associated with 143 plasma levels of gut microbiota-related metabolites profiled by untargeted metabolomics. Moreover, carbonated beverages, fruit juice, energy drinks, and bubble tea exhibited positive associations with obesity-related markers and blood lipids, which were further validated in an independent cohort of 16,851 participants from the Regional Ethnic Cohort Study in Northwest China in Shaanxi Province. In contrast, presweetened coffee was negatively associated with the obesity-related traits. A total of 79 metabolites were associated with both SSBs and metabolic markers, particularly obesity markers. Pathway enrichment analysis identified the branched-chain amino acid catabolism and aminoacyl-tRNA biosynthesis as linking SSB intake with metabolic health outcomes. Conclusion: Our findings demonstrate the associations between habitual intakes of SSBs and several metabolic markers relevant to noncommunicable diseases, and highlight the critical involvement of gut microbiota-related metabolites in mediating such associations.
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| 27. |
- Yao, Baozhen, et al.
(författare)
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LSTM-Based Vehicle Trajectory Prediction Using UAV Aerial Data
- 2023
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Ingår i: Smart Innovation, Systems and Technologies. - 2190-3026 .- 2190-3018. ; 356, s. 13-21
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Konferensbidrag (refereegranskat)abstract
- Accurately predicting the trajectory of a vehicle is a critical capability for autonomous vehicles (AVs). While human drivers can infer the future trajectory of other vehicles in the next few seconds based on information such as experience and traffic rules, most of the widely used Advance Driving Assistance Systems (ADAS) need to provide better trajectory prediction. They are usually only of limited use in emergencies such as sudden braking. In this paper, we propose a trajectory prediction network structure based on LSTM neural networks, which can accurately predict the future trajectory of a vehicle based on its historical trajectory. Unlike previous studies focusing only on trajectory prediction for highways without intersections, our network uses vehicle trajectory data from aerial photographs of intersections taken by Unmanned Aerial Vehicle (UAV). The speed of vehicles at this location fluctuates more frequently, so predicting the trajectory of vehicles at intersections is of great importance for autonomous driving.
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