| 1. |
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| 2. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 3. |
- Yao, Junying, et al.
(författare)
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Robotic grasping training using deep reinforcement learning with policy guidance mechanism
- 2021
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Ingår i: Proceedings of the ASME 2021 16th International Manufacturing Science and Engineering Conference, MSEC 2021. - : ASME International.
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Konferensbidrag (refereegranskat)abstract
- For the past few years, training robots to enable them to learn various manipulative skills using deep reinforcement learning (DRL) has arisen wide attention. However, large search space, low sample quality, and difficulties in network convergence pose great challenges to robot training. This paper deals with assembly-oriented robot grasping training and proposes a DRL algorithm with a new mechanism, namely, policy guidance mechanism (PGM). PGM can effectively transform useless or low-quality samples to useful or high-quality ones. Based on the improved Deep Q Network algorithm, an end-to-end policy model that takes images as input and outputs actions is established. Through continuous interactions with the environment, robots are able to learn how to optimally grasp objects according to the location of maximum Q value. A number of experiments for different scenarios using simulations and physical robots are conducted. Results indicate that the proposed DRL algorithm with PGM is effective in increasing the success rate of robot grasping, and moreover, is robust to changes of environment and objects. Copyright
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| 4. |
- Bowden, John A., et al.
(författare)
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Harmonizing lipidomics : NIST interlaboratory comparison exercise for lipidomics using SRM 1950-Metabolites in Frozen Human Plasma
- 2017
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Ingår i: Journal of Lipid Research. - 0022-2275 .- 1539-7262. ; 58:12, s. 2275-2288
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Tidskriftsartikel (refereegranskat)abstract
- As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks for intra-and interlaboratory quality control and method validation. These analyses were performed using nonstandardized laboratory-independent workflows. The consensus locations were also compared with a previous examination of SRM 1950 by the LIPID MAPS consortium.jlr While the central theme of the interlaboratory study was to provide values to help harmonize lipids, lipid mediators, and precursor measurements across the community, it was also initiated to stimulate a discussion regarding areas in need of improvement.
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| 5. |
- Dai, Helong, et al.
(författare)
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Blockade of CD27/CD70 pathway to reduce the generation of memory T cells and markedly prolong the survival of heart allografts in presensitized mice
- 2011
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Ingår i: Transplant Immunology. - : Elsevier BV. - 1878-5492 .- 0966-3274. ; 24:4, s. 195-202
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Tidskriftsartikel (refereegranskat)abstract
- Background: Alloreactive memory T cells are a major obstacle to transplantation acceptance due to their capacity for accelerated rejection. Methods: C57BL/6 mice that had rejected BALB/c skin grafts 4 weeks earlier were used as recipients. The recipient mice were treated with anti-CD154/LFA-1 with or without anti-CD70 during the primary skin transplantation and anti-CD154/LFA-1 or not during the secondary transplantation of BALB/c heart. We evaluated the impact of combinations of antibody-mediated blockade on the generation of memory T cells and graft survival after fully MHC-mismatched transplantations. Results: One month after the primary skin transplantation, the proportions of CD4(+) memory T cells/CD4(+) T cells and CD8(+)memory T cells/CD8(+) T cells in the anti-CD154/LFA-1 combination group were 47.32 +/- 428% and 23.18 +/- 2.77%, respectively. In the group that included anti-CD70 treatment, the proportions were reduced to 34.10 +/- 2.71% and 12.19 +/- 3.52% (P<0.05 when comparing the proportion of memory T cells between the two groups). The addition of anti-CD70 to the treatment regimen prolonged the mean survival time following secondary heart transplantation from 10 days to more than 90 days (P<0.001). Furthermore, allogenic proliferation of recipient splenic T cells and graft-infiltrating lymphocytes were significantly decreased. Meanwhile, the proportion of regulatory T cells was increased to 9.46 +/- 1.48% on day 100 post-transplantation (P<0.05). Conclusions: The addition of anti-CD70 to the anti-CD154/LFA-1 combination given during the primary transplantation reduced the generation of memory T cells. This therapy regimen provided a potential means to alleviate the accelerated rejection mediated by memory T cells during secondary heart transplantation and markedly prolong the survival of heart allografts. (C) 2011 Elsevier B.V. All rights reserved.
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| 6. |
- Liang, Xiubo, et al.
(författare)
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Menstrual Monster : A Tangible Interactive Co-educational Game Designed for Teenagers
- 2022
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Ingår i: CHI EA '22. - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450391566
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Konferensbidrag (refereegranskat)abstract
- Learning menstruation in early adolescence could reduce teenagers’ misunderstanding of it and help them treat menstruation in a proper way. This paper explored a tangible game for teenagers of different genders learning menstruation through collaborative playing. The game included five levels where users play together and learn the cause, products, symptoms of menstruation as well as try to judge some scenarios and listen to audios about menstruation. In our user study, we invited three groups of teenagers ages 11 to 16. Each group contained at least one male and one female, and we let them play the game freely. Teenagers were successfully able to play the game collaboratively, learn menstruation-related knowledge. The results revealed motivation differences related to gender, and after the game, teenagers demonstrated the observable change of the attitude towards menstruation.
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| 7. |
- Lin, Yingying, et al.
(författare)
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Arsenic trioxide is a novel agent for combination therapy to prolong heart allograft survival in allo-primed T cells transferred mice
- 2011
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Ingår i: Transplant Immunology. - : Elsevier BV. - 1878-5492 .- 0966-3274. ; 25:4, s. 194-201
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Tidskriftsartikel (refereegranskat)abstract
- Alloreactive memory T cells are major barriers to transplantation acceptance due to their capacity to accelerate rejection. Here, we investigated the effects of combined treatment with arsenic trioxide (As(2)O(3)) and blocking monoclonal antibodies (mAb) against CD154 and LFA-1 (anti-CD154/LFA-1) on graft survival as well as changes in pathology and immunological responses in mice with adoptively transferred allo-primed T cells. The mean survival time (MST) for the cardiac allografts in recipient mice receiving the combination of As(2)O(3) and anti-CD154/LFA-1 was significantly longer (>113.7 days) compared to those receiving anti-CD154/LFA-1 (232 days), As(2)O(3) (12.5 days) alone or no treatment (5.5 days). This combined strategy distinctly inhibited lymphocyte infiltration in grafts, proliferation of splenic T cells and the generation of memory T cells in spleens. Moreover, the combined treatment caused the significant down-regulation of IL-2 and IFN-gamma accompanied by increased expression of TGF-beta and regulatory T cells (Tregs) in spleens, which led to long-term cardiac allograft survival in recipient mice. These results highlight the potential application of As(2)O(3) and its contribution in combination therapy with antibody blockade to delay rejection by memory T cells. (C) 2011 Elsevier B.V. All rights reserved.
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| 8. |
- Liu, Yongkui, et al.
(författare)
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A framework for scheduling in cloud manufacturing with deep reinforcement learning
- 2019
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Ingår i: 2019 IEEE 17th International Conference on Industrial Informatics Aalto University (INDIN). - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 1775-1780
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Konferensbidrag (refereegranskat)abstract
- Cloud manufacturing is a novel service-oriented networked manufacturing paradigm that aims to provide on-demand manufacturing cloud services to consumers. Scheduling is a critical means for achieving that aim. Currently, research on scheduling in cloud manufacturing is still in its infancy, and current frequently adopted meta-heuristic algorithm-based approaches have some shortcomings, e.g. they require complex design processes and lack adaptability to dynamic environments. Deep reinforcement learning (DRL) that combines advantages of reinforcement learning and deep learning provides an efficient, adaptive and intelligent approach for solving scheduling problems in cloud manufacturing. However, to the best of our knowledge, there has been no application of DRL to scheduling in cloud manufacturing. This work conducts a preliminary exploration over this issue. First, a DRL-based framework for scheduling in cloud manufacturing is proposed. Then a DRL model for online single-task scheduling in cloud manufacturing is presented to demonstrate the effectiveness of the framework. DRL as a promising technique will find wide applications in cloud manufacturing, and this work can provide some reference for future research on this.
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| 9. |
- Liu, Yongkui, et al.
(författare)
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Logistics-involved service composition in a dynamic cloud manufacturing environment : A DDPG-based approach
- 2022
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Ingår i: Robotics and Computer-Integrated Manufacturing. - : Elsevier BV. - 0736-5845 .- 1879-2537. ; 76, s. 102323-
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Tidskriftsartikel (refereegranskat)abstract
- Service composition as an important technique for combining multiple services to construct a value-added service is a major research issue in cloud manufacturing. Highly dynamic environments present great challenges to cloud manufacturing service composition (CMfg-SC). Most of previous studies employ heuristic algorithms to solve service composition issues in cloud manufacturing, which, however, are designed for specific problems and lack adaptability necessary to dynamic environment. Hence, CMfg-SC calls for new adaptive approaches. Recent advances in deep reinforcement learning (DRL) provide a new means for solving this issue. Based on DRL, we propose a Deep Deterministic Policy Gradient (DDPG)-based service composition approach to cloud manufacturing, with which optimal service composition solutions can be learned through repeated training. Performance of DDPG in solving CMfg-SC in both static and dynamic environments is examined. Results obtained with another DRL algorithm -Deep Q-Networks (DQN) and the traditional Ant Colony Optimization (ACO) are also presented. Comparison indicates that DDPG has better adaptability, robustness, and extensibility to dynamic environments than ACO, although ACO converges faster and its steady QoS value of the service composition solution is higher than that of DDPG by 0.997%. DDPG outperforms DQN in convergence speed and stability, and the QoS value of the service composition solution of DDPG is higher than that of DQN by 3.249%.
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| 10. |
- Shao, Wei, et al.
(författare)
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CD44/CD70 blockade and anti-CD154/LFA-1 treatment synergistically suppress accelerated rejection and prolong cardiac allograft survival in mice.
- 2011
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 74, s. 430-437
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Tidskriftsartikel (refereegranskat)abstract
- Current treatments that are efficient in controlling effector T cells responses to allografts have limited efficacy on the accelerated rejection mediated by memory T cells. Effective targeting of alloreactive memory T cells may therefore be explored to improve therapeutic approaches towards solving this problem. In this study, we investigated the synergistic effect of CD44/CD70 blockade and anti-CD154/LFA-1 treatment on the accelerated rejection mediated by memory T cells. While CD44/CD70 blockade had limited effects on the alloresponses of effector T cells in vivo, it diminished the expansion of both CD4(+) and CD8(+) memory T cells in recipients adoptively transferred with donor-sensitized T cells. In combination with anti-CD154/LFA-1 treatment, CD44/CD70 blockade significantly prolonged cardiac allograft survival in adoptive transfer recipients. We demonstrated that treatment with the combination of all four antibodies (anti-CD154/LFA-1/CD44/CD70) inhibited accelerated rejection by markedly suppressing the alloresponses of effector and memory T cells and reducing the number of graft-infiltration lymphocytes in adoptive transfer recipients. Meanwhile, CD44/CD70 blockade and anti-CD154/LFA-1 treatment synergically enhanced regulatory T cells (Tregs) by increasing the proportion of splenic Tregs and the expression of IL-10 in these recipients. Our findings contribute to the potential design of therapies for accelerated allograft rejection.
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| 11. |
- Stanaway, Jeffrey D., et al.
(författare)
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Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990-2017: A systematic analysis for the Global Burden of Disease Study 2017
- 2018
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Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1923-1994
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Tidskriftsartikel (refereegranskat)abstract
- Background The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 comparative risk assessment (CRA) is a comprehensive approach to risk factor quantification that offers a useful tool for synthesising evidence on risks and risk-outcome associations. With each annual GBD study, we update the GBD CRA to incorporate improved methods, new risks and risk-outcome pairs, and new data on risk exposure levels and risk- outcome associations. Methods We used the CRA framework developed for previous iterations of GBD to estimate levels and trends in exposure, attributable deaths, and attributable disability-adjusted life-years (DALYs), by age group, sex, year, and location for 84 behavioural, environmental and occupational, and metabolic risks or groups of risks from 1990 to 2017. This study included 476 risk-outcome pairs that met the GBD study criteria for convincing or probable evidence of causation. We extracted relative risk and exposure estimates from 46 749 randomised controlled trials, cohort studies, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. Using the counterfactual scenario of theoretical minimum risk exposure level (TMREL), we estimated the portion of deaths and DALYs that could be attributed to a given risk. We explored the relationship between development and risk exposure by modelling the relationship between the Socio-demographic Index (SDI) and risk-weighted exposure prevalence and estimated expected levels of exposure and risk-attributable burden by SDI. Finally, we explored temporal changes in risk-attributable DALYs by decomposing those changes into six main component drivers of change as follows: (1) population growth; (2) changes in population age structures; (3) changes in exposure to environmental and occupational risks; (4) changes in exposure to behavioural risks; (5) changes in exposure to metabolic risks; and (6) changes due to all other factors, approximated as the risk-deleted death and DALY rates, where the risk-deleted rate is the rate that would be observed had we reduced the exposure levels to the TMREL for all risk factors included in GBD 2017.
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| 12. |
- Wang, Yan, et al.
(författare)
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Evaluation of precipitable water vapor from four satellite products and four reanalysis datasets against GPS measurements on the Southern Tibetan Plateau
- 2017
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Ingår i: Journal of Climate. - 0894-8755. ; 30, s. 5699-5713
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Tidskriftsartikel (refereegranskat)abstract
- © 2017 American Meteorological Society. The southern Tibetan Plateau (STP) is the region in which water vapor passes from South Asia into the Tibetan Plateau (TP). The accuracy of precipitable water vapor (PWV) modeling for this region depends strongly on the quality of the available estimates of water vapor advection and the parameterization of land evaporation models. While climate simulation is frequently improved by assimilating relevant satellite and reanalysis products, this requires an understanding of the accuracy of these products. In this study, PWV data from MODIS infrared and near-infrared measurements, AIRS Level-2 and Level-3, MERRA, ERA-Interim, JRA-55, and NCEP final reanalysis (NCEP-Final) are evaluated against ground-based GPS measurements at nine stations over the STP, which covers the summer monsoon season from 2007 to 2013. The MODIS infrared product is shown to underestimate water vapor levels by more than 20% (1.84 mm), while the MODIS near-infrared product overestimates them by over 40% (3.52 mm). The AIRS PWV product appears to be most useful for constructing high-resolution and high-quality PWV datasets over the TP; particularly the AIRS Level-2 product has a relatively low bias (0.48 mm) and RMSE (1.83 mm) and correlates strongly with the GPS measurements (R = 0.90). The four reanalysis datasets exhibit similar performance in terms of their correlation coefficients (R = 0.87-0.90), bias (0.72-1.49 mm), and RMSE (2.19-2.35 mm). The key finding is that all the reanalyses have positive biases along the PWV seasonal cycle, which is linked to the well-known wet bias over the TP of current climate models.
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| 13. |
- Wang, Yan, et al.
(författare)
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Synergy of orographic drag parameterization and high resolution greatly reduces biases of WRF-simulated precipitation in central Himalaya
- 2020
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Ingår i: Climate Dynamics. - : Springer Science and Business Media LLC. - 0930-7575 .- 1432-0894. ; 54:3-4, s. 1729-40
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Tidskriftsartikel (refereegranskat)abstract
- Current climate models often have significant wet biases in the Tibetan Plateau and encounter particular difficulties in representing the climatic effect of the Central Himalaya Mountain (CHM), where the gradient of elevation is extremely steep and the terrain is complex. Yet, there were few studies dealing with the issue in the high altitudes of this region. In order to improve climate modeling in this region, a network consisting of 14 rain gauges was set up at elevations >2800 m above sea level along a CHM valley. Numerical experiments with Weather Research and Forecasting model were conducted to investigate the effects of meso- and micro-scale terrain on water vapor transport and precipitation. The control case uses a high horizontal resolution (0.03°) and a Turbulent Orographic Form Drag (TOFD) scheme to resolve the mesoscale terrain and to represent sub-grid microscale terrain effect. The effects of the horizontal resolution and the TOFD scheme were then analyzed through comparisons with sensitivity cases that either use a low horizontal resolution (0.09°) or switch off the TOFD scheme. The results show that the simulations with high horizontal resolution, even without the TOFD scheme, can not only increase the spatial consistency (correlation coefficient 0.84–0.92) between the observed and simulated precipitation, but also considerably reduce the wet bias by more than 250%. Adding the TOFD scheme further reduces the precipitation bias by 50% or so at almost all stations in the CHM. The TOFD scheme reduces precipitation intensity, especially heavy precipitation (>10 mm h−1) over high altitudes of the CHM. Both high horizontal resolution and TOFD enhance the orographic drag to slow down wind; as a result, less water vapor is transported from lowland to the high altitudes of CHM, causing more precipitation at lowland area of the CHM and less at high altitudes of CHM. Therefore, in this highly terrain-complex region, it is crucial to use a high horizontal resolution to depict mesoscale complex terrain and a TOFD scheme to parameterize the drag caused by microscale complex terrain.
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| 14. |
- Xu, Kangjun, et al.
(författare)
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Association between serum vitamin B12 and risk of all-cause mortality in elderly adults : a prospective cohort study
- 2021
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Ingår i: BMC Geriatrics. - : BioMed Central. - 1471-2318. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: Results from previous studies that linking vitamin B12 to risk of chronic diseases or mortality are inconsistent. We hereby explore the association between serum concentration of vitamin B12 and all-cause mortality risk in elderly adults.METHODS: Participants aged over 65 years in the Chinese Longitudinal Healthy Longevity Survey were included in present prospective cohort study. Serum vitamin B12 was assessed at the 2011-2012 and 2014 wave, respectively. Participants were divided into three groups based on two cut-off points - 10th and 90th percentiles of vitamin B12 concentrations - in the whole population. Cox regression model was used to calculate the hazard ratio (HR) and 95 % confidence intervals (95 % CIs), and restricted cubic spline function was further modelled to investigate their dose-response associations.RESULTS: Among 2,086 participants [mean ± SD: 87.74 ± 11.24 years, 908 (43.53 %) males], 943 (45.21 %) died during an average follow-up of 3.34 (SD: 1.63) years. Comparing with participants with middle concentration of serum vitamin B12, participants with high concentration had an increased risk of all-cause mortality [HR (95 %CIs): 1.30 (1.03-1.64)], whereas participants with low concentration had an insignificantly decreased risk of all-cause mortality (0.96, 0.76-1.20). The positive association between high concentration of serum vitamin B12 and all-cause mortality was also observed among the male and in a series of sensitivity analyses. In the dose-response analysis, a J-shape pattern was observed, but the non-linear association was only significant in males (Pnon-linearity = 0.0351).CONCLUSIONS: High concentration of serum vitamin B12 was associated with an increased risk of all-cause mortality in a J-shaped pattern. The precise mechanisms underlying the association remain to be explored.
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| 15. |
- Zhao, Zhuohui, et al.
(författare)
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Ambient carbon monoxide associated with alleviated respiratory inflammation in healthy young adults
- 2016
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 208, s. 294-298
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Tidskriftsartikel (refereegranskat)abstract
- There is increasing controversy on whether acute exposure to ambient carbon monoxide (CO) is hazardous on respiratory health. We therefore performed a longitudinal panel study to evaluate the acute effects of ambient CO on fractional exhaled nitric oxide (FeNO), a well-established biomarker of airway inflammation. We completed 4-6 rounds of health examinations among 75 healthy young adults during April to June in 2013 in Shanghai, China. We applied the linear mixed-effect model to investigate the short-term associations between CO and FeNO. CO exposure during 2-72 h preceding health tests was significantly associated with decreased FeNO levels. For example, an interquartile range increase (0.3 mg/m(3)) of 2-h CO exposure corresponded to 10.6% decrease in FeNO. This association remained when controlling for the concomitant exposure to co-pollutants. This study provided support that short-term exposure to ambient CO might be related with reduced levels of FeNO, a biomarker of lower airway inflammation.
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| 16. |
- Zheng, Lirong, et al.
(författare)
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Photocatalytic activity of ZnO/Sn1-xZnxO2-x nanocatalysts : A synergistic effect of doping and heterojunction
- 2014
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Ingår i: Applied Catalysis B. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 148, s. 44-50
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Tidskriftsartikel (refereegranskat)abstract
- A novel configuration of porous ZnO/Sn1-xZnxO2-x, heterojunction nanocatalyst with high photocatalytic activity was successfully synthesized through a simple two-step solvothermal method. Porous Sn1-xZnxO2, was synthesized from Zn2+ and Sn4+ precursors with the Zn/Sn ratio of 2:1 in the absence of alkali, and then intermolecular dehydrolysis led to the formation of heterointerface between Sn1-xZnxO2, and ZnO. The results show that Zn2+ doping exhibits a significant influence on particle size of SnO2 leading to much higher specific surface area and larger band gap, which is in favor of the photocatalytic activity of SnO2 under UV light irradiation. In addition, the formation of ZnO/Sn1-xZnxO2 heterostructure improves the separation of photogenerated electron hole pairs due to the potential difference between Sn1-xZnxO2, and ZnO, which also benefits to photocatalysis. By taking account of them together, these results provide further insight into the synergistic effects of metal ion doping and semiconductor/semiconductor heterostructure on the activity of photocatalysts in environmental remediation applications. (C) 2013 Elsevier B.V. All rights reserved.
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