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1
Li, Zhenjie, Hui Tao, Heike Hartmann, Buda Su, Yanjun Wang, and Tong Jiang. "Variation of Projected Atmospheric Water Vapor in Central Asia Using Multi-Models from CMIP6." Atmosphere 11, no. 9 (August 26, 2020): 909. http://dx.doi.org/10.3390/atmos11090909.
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Using data from the Integrated Global Radiosonde Archive Version 2 (IGRA2) and the Multi Model Ensemble (MME) of four global climate models (GCMs), named CanESM5, IPSL-CM6A-LR, MIROC6, and MRI-ESM2-0, within the framework of phase 6 of the Coupled Model Intercomparison Project (CMIP6), we analyzed the changes in atmospheric total column water vapor (TCWV) over Central Asia in the future (2021–2100) under SSP-RCPs scenarios: SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5, relative to baseline period (1986–2005). Results showed that the annual mean TCWV from IGRA2 was consistent with the model output from 1979 to 2014 in Central Asia. Besides, the spatial distribution of TCWV in Central Asia during the baseline period was consistent between the models. The regional average value of Central Asia was between 10.8 mm and 12.4 mm, and decreased with elevation. TCWV will increase under different SSP-RCPs from 2021 to 2040, but showed different trends after 2040. It will increase under SSP1-1.9 and SSP1-2.6 scenarios from 2021 to 2050, and decrease after that. It will grow from 2021 to 2055 under SSP4-3.4 scenario, and then stay essentially constant. Under SSP2-4.5 and SSP4-6.0 scenarios, TCWV will rise rapidly during 2021–2065, but the growth will decline from 2065 to 2100. TCWV will continue to increase under SSP3-7.0 and SSP5-8.5 scenarios, and the largest increase is projected under SSP5-8.5 scenario. Change in near-surface temperature (Ts) matched the change in TCWV, but changes in precipitation and evapotranspiration are not significant during 2021–2100. In spite of the large variations in TCWV under different SSP-RCPs, the dominant characteristic in all scenarios shows that a large TCWV increase is demonstrated over areas with small TCWV amounts during the baseline period. On the contrary, increases will be small where the TCWV amounts had been large during the baseline period. The change in TCWV is highly correlated to the increase in Ts in Central Asia. Under SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5 scenarios, the higher the temperature due to higher radiative forcing, the steeper the regression slope between TCWV and Ts change. It is closest to the theoretical value of the Clausius-Clapeyron equation under SSP3-7.0 and SSP5-8.5 scenarios, but not presented under other scenarios. Spatially, steeper regression slopes during 2021–2100 have been found around the Caspian Sea in the southwest and in the high-elevation areas in the southeast of Central Asia, which is likely related to the abundant local water supply for evaporation.
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Shang, Lin, Jiali Luo, and Chunxiao Wang. "Ozone Variation Trends under Different CMIP6 Scenarios." Atmosphere 12, no. 1 (January 14, 2021): 112. http://dx.doi.org/10.3390/atmos12010112.
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This study compares and analyzes simulations of ozone under different scenarios by three CMIP6 models (IPSL-CM6A, MRI-ESM2 and CESM-WACCM). Results indicate that as the social vulnerability and anthropogenic radiative forcing is increasing, the change of total column ozone in the tropical stratosphere is not linear. Compared to the SSP2-4.5 and SSP5-8.5 scenarios, the SSP1-2.6 and SSP3-7.0 are more favorable for the increase in stratospheric ozone mass in the tropics. Arctic ozone would never recover under the SSP1-2.6 scenario; however, the Antarctica ozone would gradually recover in all scenarios. Under the SSP1-2.6 and SSP2-4.5 scenarios, the trend of tropical total column ozone is mainly determined by the trend of column ozone in the tropical troposphere. Under the SSP3-7.0 scenario, tropospheric ozone concentration will significantly increase; under the SSP5-8.5 scenario, ozone concentration will distinctly increase in the middle and lower troposphere.
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Guo, Aijun, Daiwei Jiang, Fanglei Zhong, Xiaojiang Ding, Xiaoyu Song, Qingping Cheng, Yongnian Zhang, and Chunlin Huang. "Prediction of Technological Change under Shared Socioeconomic Pathways and Regional Differences: A Case Study of Irrigation Water Use Efficiency Changes in Chinese Provinces." Sustainability 11, no. 24 (December 11, 2019): 7103. http://dx.doi.org/10.3390/su11247103.
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Technological changes in water use efficiency directly influence regional sustainable development. However, few studies have attempted to predict changes in water use efficiency because of the complex influencing factors and regional diversity. The Chinese Government has established a target of 0.6 for the effective utilization coefficient of irrigation water, but it is not clear how the coefficient will change in different provinces in the future. The purpose of this study is to predict irrigation water use efficiency changes using a conditional convergence model and combined with the shared socioeconomic pathways (SSPs) scenario settings and hydro-economic (HE) classification to group 31 Chinese provinces by their different economic and water resources conditions. The results show that the coefficient exponentially converges to 0.6 in half the provinces under SSP1 (sustainability), SSP2 (middle of the road), and SSP5 (conventional development) by 2030, whereas SSP3 (fragmentation) and SSP4 (inequality) are generally inefficient development pathways. HE-3 provinces (strong economic capacity, substantial hydrological challenges) achieve the greatest efficiency improvements (with all coefficients above 0.6), and SSP1 is a suitable pathway for these provinces. HE-2 provinces (strong economic capacities, low hydrological challenges) have relatively low efficiency because they lack incentives to save water, and SSP1 is also suitable for these provinces. For most HE-1 provinces (low economic capacity, low hydrological challenges), the coefficients are less than 0.6, and efforts are required to enhance their economic capacity under SSP1 or SSP5. HE-4 provinces (low economic capacity, substantial hydrological challenges) would improve efficiency in a cost-efficient manner under SSP2.
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Keeble, James, Birgit Hassler, Antara Banerjee, Ramiro Checa-Garcia, Gabriel Chiodo, Sean Davis, Veronika Eyring, et al. "Evaluating stratospheric ozone and water vapour changes in CMIP6 models from 1850 to 2100." Atmospheric Chemistry and Physics 21, no. 6 (March 31, 2021): 5015–61. http://dx.doi.org/10.5194/acp-21-5015-2021.
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Abstract. Stratospheric ozone and water vapour are key components of the Earth system, and past and future changes to both have important impacts on global and regional climate. Here, we evaluate long-term changes in these species from the pre-industrial period (1850) to the end of the 21st century in Coupled Model Intercomparison Project phase 6 (CMIP6) models under a range of future emissions scenarios. There is good agreement between the CMIP multi-model mean and observations for total column ozone (TCO), although there is substantial variation between the individual CMIP6 models. For the CMIP6 multi-model mean, global mean TCO has increased from ∼ 300 DU in 1850 to ∼ 305 DU in 1960, before rapidly declining in the 1970s and 1980s following the use and emission of halogenated ozone-depleting substances (ODSs). TCO is projected to return to 1960s values by the middle of the 21st century under the SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5 scenarios, and under the SSP3-7.0 and SSP5-8.5 scenarios TCO values are projected to be ∼ 10 DU higher than the 1960s values by 2100. However, under the SSP1-1.9 and SSP1-1.6 scenarios, TCO is not projected to return to the 1960s values despite reductions in halogenated ODSs due to decreases in tropospheric ozone mixing ratios. This global pattern is similar to regional patterns, except in the tropics where TCO under most scenarios is not projected to return to 1960s values, either through reductions in tropospheric ozone under SSP1-1.9 and SSP1-2.6, or through reductions in lower stratospheric ozone resulting from an acceleration of the Brewer–Dobson circulation under other Shared Socioeconomic Pathways (SSPs). In contrast to TCO, there is poorer agreement between the CMIP6 multi-model mean and observed lower stratospheric water vapour mixing ratios, with the CMIP6 multi-model mean underestimating observed water vapour mixing ratios by ∼ 0.5 ppmv at 70 hPa. CMIP6 multi-model mean stratospheric water vapour mixing ratios in the tropical lower stratosphere have increased by ∼ 0.5 ppmv from the pre-industrial to the present-day period and are projected to increase further by the end of the 21st century. The largest increases (∼ 2 ppmv) are simulated under the future scenarios with the highest assumed forcing pathway (e.g. SSP5-8.5). Tropical lower stratospheric water vapour, and to a lesser extent TCO, shows large variations following explosive volcanic eruptions.
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Nooni, Isaac Kwesi, Daniel Fiifi T. Hagan, Guojie Wang, Waheed Ullah, Jiao Lu, Shijie Li, Mawuli Dzakpasu, Nana Agyemang Prempeh, and Kenny T. C. Lim Kam Sian. "Future Changes in Simulated Evapotranspiration across Continental Africa Based on CMIP6 CNRM-CM6." International Journal of Environmental Research and Public Health 18, no. 13 (June 23, 2021): 6760. http://dx.doi.org/10.3390/ijerph18136760.
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The main goal of this study was to assess the interannual variations and spatial patterns of projected changes in simulated evapotranspiration (ET) in the 21st century over continental Africa based on the latest Shared Socioeconomic Pathways and the Representative Concentration Pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) provided by the France Centre National de Recherches Météorologiques (CNRM-CM) model in the Sixth Phase of Coupled Model Intercomparison Project (CMIP6) framework. The projected spatial and temporal changes were computed for three time slices: 2020–2039 (near future), 2040–2069 (mid-century), and 2080–2099 (end-of-the-century), relative to the baseline period (1995–2014). The results show that the spatial pattern of the projected ET was not uniform and varied across the climate region and under the SSP-RCPs scenarios. Although the trends varied, they were statistically significant for all SSP-RCPs. The SSP5-8.5 and SSP3-7.0 projected higher ET seasonality than SSP1-2.6 and SSP2-4.5. In general, we suggest the need for modelers and forecasters to pay more attention to changes in the simulated ET and their impact on extreme events. The findings provide useful information for water resources managers to develop specific measures to mitigate extreme events in the regions most affected by possible changes in the region’s climate. However, readers are advised to treat the results with caution as they are based on a single GCM model. Further research on multi-model ensembles (as more models’ outputs become available) and possible key drivers may provide additional information on CMIP6 ET projections in the region.
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Hashimoto, Shingo, Yuta Shibamoto, Hiromitsu Iwata, Hiroyuki Ogino, Hiroki Shibata, Toshiyuki Toshito, Chikao Sugie, and Jun-etsu Mizoe. "Whole-pelvic radiotherapy with spot-scanning proton beams for uterine cervical cancer: a planning study." Journal of Radiation Research 57, no. 5 (September 1, 2016): 524–32. http://dx.doi.org/10.1093/jrr/rrw052.
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Abstract The aim of this study was to compare the dosimetric parameters of whole-pelvic radiotherapy (WPRT) for cervical cancer among plans involving 3D conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), or spot-scanning proton therapy (SSPT). The dose distributions of 3D-CRT-, IMRT-, and SSPT-based WPRT plans were compared in 10 patients with cervical cancer. All of the patients were treated with a prescribed dose of 50.4 Gy in 1.8-Gy daily fractions, and all of the plans involved the same planning target volume (PTV) constrictions. A 3D-CRT plan involving a four-field box, an IMRT plan involving seven coplanar fields, and an SSPT plan involving four fields were created. The median PTV D95% did not differ between the 3D-CRT, IMRT and SSPT plans. The median conformity index 95% and homogeneity index of the IMRT and SSPT were better than those of the 3D-CRT. The homogeneity index of the SSPT was better than that of the IMRT. SSPT resulted in lower median V20 values for the bladder wall, small intestine, colon, bilateral femoral heads, skin, and pelvic bone than IMRT. Comparing the Dmean values, SSPT spared the small intestine, colon, bilateral femoral heads, skin and pelvic bone to a greater extent than the other modalities. SSPT can reduce the irradiated volume of the organs at risk compared with 3D-CRT and IMRT, while maintaining excellent PTV coverage. Further investigations of SSPT are warranted to assess its role in the treatment of cervical cancer.
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Bagyan, Irina, Barbara Setlow, and Peter Setlow. "New Small, Acid-Soluble Proteins Unique to Spores ofBacillus subtilis: Identification of the Coding Genes and Regulation and Function of Two of These Genes." Journal of Bacteriology 180, no. 24 (December 15, 1998): 6704–12. http://dx.doi.org/10.1128/jb.180.24.6704-6712.1998.
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ABSTRACT Eleven small, acid-soluble proteins (SASP) which are present in spores but not in growing cells of Bacillus subtilis were identified by sequence analysis of proteins separated by acrylamide gel electrophoresis of acid extracts from spores which lack the three major SASP (α, β, and γ). Six of these proteins are encoded by open reading frames identified previously or by analysis of the complete sequence of the B. subtilis genome, including two minor α/β-type SASP (SspC and SspD) and a putative spore coat protein (CotK). Five proteins are encoded by short open reading frames that were not identified as coding regions in the analysis of the completeB. subtilis genomic sequence. Studies of the regulation of two of the latter genes, termed sspG and sspJ, showed that both are expressed only in sporulation. ThesspG gene is transcribed in the mother cell compartment by RNA polymerase with the mother cell-specific sigma factor for RNA polymerase, ςK, and is cotranscribed with a downstream gene, yurS; sspG transcription also requires the DNA binding protein GerE. In contrast, sspJ is transcribed in the forespore compartment by RNA polymerase with the forespore-specific ςG and appears to give a monocistronic transcript. A mutation eliminating SspG had no effect on sporulation or spore properties, while loss of SspJ caused a slight decrease in the rate of spore outgrowth in an otherwise wild-type background.
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Gray, Robert M., Richard M. Marshall, Ronald B. Livingston, and Ruth A. Haak. "Use of the Long vs Short Form of the Speech Sounds Perception Test in a School-Age Population." Perceptual and Motor Skills 82, no. 2 (April 1996): 475–80. http://dx.doi.org/10.2466/pms.1996.82.2.475.
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A sample of 645 school-age children, ages 9 to 14 years, were administered independent forms of the Speech Sounds Perception Test for older children. 328 subjects took the complete test (SSPT-60) and 317 were administered only the first 30 items (SSPT-30). Comparison of mean errors indicated that significantly more errors were made by subjects given the SSPT-30. Decisions regarding the use of each form for school-age children are discussed.
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Onyutha, Charles, Arnold Asiimwe, Brian Ayugi, Hamida Ngoma, Victor Ongoma, and Hossein Tabari. "Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda: CMIP6 Projections." Atmosphere 12, no. 7 (July 8, 2021): 887. http://dx.doi.org/10.3390/atmos12070887.
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We used CMIP6 GCMs to quantify climate change impacts on precipitation and potential evapotranspiration (PET) across water management zones (WMZs) in Uganda. Future changes are assessed based on four Shared Socioeconomic Pathways (SSP) scenarios including SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 over the periods 2021–2040, 2041–2060, 2061–2080, and 2081–2100. Both precipitation and PET are generally projected to increase across all the WMZs. Annual PET in the 2030s, 2050s, 2070s, 2090s will increase in the ranges 1.1–4.0%, 4.8–7.9%, 5.1–11.8%, and 5.3–17.1%, respectively. For the respective periods, annual precipitation will increase in the ranges 4.0–7.8%, 7.8–12.5%, 7.9–19.9%, and 6.9–26.3%. The lower and upper limits of these change ranges for both precipitation and PET are, respectively, derived under SSP1-2.6 and SSP5-8.5 scenarios. Climate change will impact on PET or precipitation disproportionately across the WMZs. While the eastern WMZ (Kyoga) will experience the largest projected precipitation increase especially towards the end of the century, the southern WMZ (Victoria) exhibited the largest PET increase. Our findings are relevant for understanding hydrological impacts of climate change across Uganda, in the background of global warming. Thus, the water sector should devise and implement adaptation measures to impede future socioeconomic and environmental crises in the country.
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Tebaldi, Claudia, Kevin Debeire, Veronika Eyring, Erich Fischer, John Fyfe, Pierre Friedlingstein, Reto Knutti, et al. "Climate model projections from the Scenario Model Intercomparison Project (ScenarioMIP) of CMIP6." Earth System Dynamics 12, no. 1 (March 1, 2021): 253–93. http://dx.doi.org/10.5194/esd-12-253-2021.
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Abstract. The Scenario Model Intercomparison Project (ScenarioMIP) defines and coordinates the main set of future climate projections, based on concentration-driven simulations, within the Coupled Model Intercomparison Project phase 6 (CMIP6). This paper presents a range of its outcomes by synthesizing results from the participating global coupled Earth system models. We limit our scope to the analysis of strictly geophysical outcomes: mainly global averages and spatial patterns of change for surface air temperature and precipitation. We also compare CMIP6 projections to CMIP5 results, especially for those scenarios that were designed to provide continuity across the CMIP phases, at the same time highlighting important differences in forcing composition, as well as in results. The range of future temperature and precipitation changes by the end of the century (2081–2100) encompassing the Tier 1 experiments based on the Shared Socioeconomic Pathway (SSP) scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) and SSP1-1.9 spans a larger range of outcomes compared to CMIP5, due to higher warming (by close to 1.5 ∘C) reached at the upper end of the 5 %–95 % envelope of the highest scenario (SSP5-8.5). This is due to both the wider range of radiative forcing that the new scenarios cover and the higher climate sensitivities in some of the new models compared to their CMIP5 predecessors. Spatial patterns of change for temperature and precipitation averaged over models and scenarios have familiar features, and an analysis of their variations confirms model structural differences to be the dominant source of uncertainty. Models also differ with respect to the size and evolution of internal variability as measured by individual models' initial condition ensemble spreads, according to a set of initial condition ensemble simulations available under SSP3-7.0. These experiments suggest a tendency for internal variability to decrease along the course of the century in this scenario, a result that will benefit from further analysis over a larger set of models. Benefits of mitigation, all else being equal in terms of societal drivers, appear clearly when comparing scenarios developed under the same SSP but to which different degrees of mitigation have been applied. It is also found that a mild overshoot in temperature of a few decades around mid-century, as represented in SSP5-3.4OS, does not affect the end outcome of temperature and precipitation changes by 2100, which return to the same levels as those reached by the gradually increasing SSP4-3.4 (not erasing the possibility, however, that other aspects of the system may not be as easily reversible). Central estimates of the time at which the ensemble means of the different scenarios reach a given warming level might be biased by the inclusion of models that have shown faster warming in the historical period than the observed. Those estimates show all scenarios reaching 1.5 ∘C of warming compared to the 1850–1900 baseline in the second half of the current decade, with the time span between slow and fast warming covering between 20 and 27 years from present. The warming level of 2 ∘C of warming is reached as early as 2039 by the ensemble mean under SSP5-8.5 but as late as the mid-2060s under SSP1-2.6. The highest warming level considered (5 ∘C) is reached by the ensemble mean only under SSP5-8.5 and not until the mid-2090s.
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Wyser, Klaus, Torben Koenigk, Uwe Fladrich, Ramon Fuentes-Franco, Mehdi Pasha Karami, and Tim Kruschke. "The SMHI Large Ensemble (SMHI-LENS) with EC-Earth3.3.1." Geoscientific Model Development 14, no. 7 (July 30, 2021): 4781–96. http://dx.doi.org/10.5194/gmd-14-4781-2021.
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Abstract. The Swedish Meteorological and Hydrological Institute used the global climate model EC-Earth3 to perform a large ensemble of simulations (SMHI-LENS). It consists of 50 members, covers the period 1970 to 2100, and comprises the SSP1-1.9, SSP3-3.4, SSP5-3.4-OS, and SSP5-8.5 scenarios. Thus, it is currently the only large ensemble that allows for analyzing the effect of delayed mitigation actions versus no mitigation efforts and versus earlier efforts leading to similar radiative forcing at the year 2100. We describe the set-up of the SMHI-LENS in detail and provide first examples of its application. The ensemble mean future changes in key variables in the atmosphere and ocean are analyzed and compared against the variability across the ensemble members. In agreement with other large-ensemble simulations, we find that the future changes in the near-surface temperature are more robust than those for precipitation or sea level pressure. As an example of a possible application of the SMHI-LENS, we analyze the probability of exceeding specific global surface warming levels in the different scenarios. None of the scenarios is able to keep global warming in the 21st century below 1.5 ∘C. In SSP1-1.9 there is a probability of approximately 70 % to stay below 2 ∘C warming, while all other SSPs exceed this target in every single member of SMHI-LENS during the course of the century. We also investigate the point in time when the SSP5-8.5 and SSP5-3.4 ensembles separate, i.e., when their differences become significant, and likewise when the SSP5-3.4-OS and SSP4-3.4 ensembles become similar. Last, we show that the time of emergence of a separation between different scenarios can vary by several decades when reducing the ensemble size to 10 members.
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Li, Jiao, Yang Zhao, and Zhenfei Tang. "Projection of Future Summer Precipitation over the Yellow River Basin: A Moisture Budget Perspective." Atmosphere 11, no. 12 (December 2, 2020): 1307. http://dx.doi.org/10.3390/atmos11121307.
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The projection of future precipitation over the Yellow River Basin (YRB) is of great importance to regional climate change adaptation and mitigation. Using the historical simulations and projections under the four combined scenarios of the shared socioeconomic pathways and the forcing levels of the Representative Concentration Pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) provided by the multimodel ensemble mean of 10 models in phase six of the Coupled Model Intercomparison Project (CMIP6), the projected spatial and temporal changes of future summer precipitation over the YRB and the possible physical mechanisms underlying future summer precipitation changes are investigated. Large discrepancies in precipitation exist among the four scenarios during the latter half period of the 21st century, with precipitation under SSP5-8.5 being the largest. Nevertheless, the precipitation under each of the four scenarios shows a similar spatial pattern over the YRB, with an east–west-oriented gradient. A comparison of projected moisture transport into the YRB among the four scenarios reveals two channels (westerlies and monsoon flow) under SSP5-8.5, whereas the monsoon flow from adjacent oceans is important under the other three scenarios. Further analysis of the unique features of the projected moisture flux and substantial increase in summer precipitation under SSP5-8.5 indicates that the future summer precipitation trend over the YRB can be mainly attributed to an increase in evaporation and moisture advection.
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Suda, Takashi, Hisato Ishizawa, Hiromitsu Nagano, Takahiro Negi, Hiroshi Kawai, Daisuke Tochii, Sachiko Tochii, and Yasushi Hoshikawa. "Early outcomes in 147 consecutive cases of subxiphoid single-port thymectomy and evaluation of learning curves." European Journal of Cardio-Thoracic Surgery 58, Supplement_1 (July 4, 2020): i44—i49. http://dx.doi.org/10.1093/ejcts/ezaa183.
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Abstract OBJECTIVES The aim of the present study was to examine some initial results and learning curves concerning subxiphoid single-port thymectomy (SSPT), thereby clarifying the safety of this surgical approach and describing the precautions for adopting it. METHODS From March 2011 to August 2019, a total of 203 patients underwent thymectomy for either anterior mediastinal tumours or myasthenia gravis at Fujita Health University Hospital. Of these 203 patients, 147 patients who had undergone SSPT were selected as participants for the present study. RESULTS Of the 147 cases, transition to a different approach was required in three (2.0%) cases: two (1.3%) cases transitioned to median sternotomy, whereas one (0.7%) case transitioned to the side chest trans-intercostal approach. The two cases that transitioned to median sternotomy were the second cases for different operators after they began performing this technique. There were six (4.0%) cases with complications and no deaths. The operation time cumulative summation learning curve analysis revealed that the curves descended from the 38th case. In the 83 cases handled by one surgeon, the learning curves descended from the 31st case. CONCLUSIONS SSPT is a safe modality with few complications and no associated cases of mortality reported. Operators are required to experience 31–38 cases until the operation time for SSPT was stabilized. Special care should be exercised to prevent vascular damage in the vicinity of the innominate veins during the early stages after SSPT introduction.
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Bello, Mojeed Olalekan, N. Abdus-Salam, N. A. Odebunmi, and A. A. Jimoh. "GEO- AND PHYTO-MONITORING OF ENVIRONMENTAL IMPACT OF SMELTING INDUSTRY IN IKIRUN, NIGERIA." FUDMA JOURNAL OF SCIENCES 4, no. 4 (June 13, 2021): 302–8. http://dx.doi.org/10.33003/fjs-2020-0404-486.
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This research monitored the level of some heavy metals in soil and a plant species around iron smelting industry. The soil in different depths D1 (0 -10 cm), D2 (10 – 20 cm) and D3 (20 -30 cm) and plant (Tithonia diversifolia) known as Mexican sunflower were sampled in four soil sampling points (SSP) and plant sampling points (PSP) which are 50, 100, 150 and 200 m away from the industry. The concentrations of Cr, Cu, Fe, Pb and Zn in the soil and plant digest were determined using Atomic Absorption Spectroscopy (AAS). Some physicochemical properties like pH, electrical conductivity and organic matter were also measured. The result of the analysis of the heavy metals in the soil was in the sequence Fe > Zn > Cu >Pb> Cr at SSP1 SSP2 and SSP4 while Fe > Zn > Cu > Cr > Pb at SSP3. In the plant, the result showed the presence of these heavy metals except Pb which was not present in any sampling points. The concentration of iron (Fe) in the plant decreased away from PSP1 to PSP4 around the industry. The physicochemical properties like pH which influenced the availability of metals in soil were found to increase away from SSP1 to SSP4 and consequently its effect on the concentration of these heavy metals in plants, particularly for Fe and Zn. Although, heavy metals monitored were within the permissible limit of WHO except Fe in soil, the trend of their presence in
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Hébert2, Martine, Marie-Ève Daspe, Martin Blais, Francine Lavoie, and Mireille Guerrier. "Agression sexuelle et violence dans les relations amoureuses." Criminologie 50, no. 1 (May 9, 2017): 157–79. http://dx.doi.org/10.7202/1039800ar.
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Cette étude vise à documenter le rôle médiateur des symptômes de stress post-traumatique (SSPT) dans le lien entre l’agression sexuelle et différentes formes de victimisation vécues dans le contexte de relations amoureuses. L’étude se fonde sur l'Enquête sur les parcours amoureux des jeunes (PAJ), réalisée au sein de 34 écoles secondaires du Québec. Les jeunes ont rempli un questionnaire portant sur leurs expériences de victimisation, y compris l’agression sexuelle vécue pendant l’enfance et la violence psychologique, physique et sexuelle vécue au sein de leurs relations amoureuses dans les 12 derniers mois. Les SSPT ont été évalués à l’aide du UCLA PTSD Index. Sur un total de 8 194 adolescents, 15 % des filles et 4 % des garçons ont rapporté avoir vécu une agression sexuelle. Les résultats des analyses acheminatoires semblent indiquer que le fait d’avoir été victime d’agression sexuelle est associé à davantage de SSPT et qu’en retour, les SSPT sont positivement associés à la violence psychologique, physique et sexuelle subie de la part d’un partenaire amoureux. Cette étude comporte des implications pratiques pour la prévention et l’intervention sur le plan de la violence dans les relations amoureuses chez les victimes d’agression sexuelle.
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Hong, Juyoung, Khadijeh Javan, Yonggwan Shin, and Jeong-Soo Park. "Future Projections and Uncertainty Assessment of Precipitation Extremes in Iran from the CMIP6 Ensemble." Atmosphere 12, no. 8 (August 16, 2021): 1052. http://dx.doi.org/10.3390/atmos12081052.
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Scientists who want to know future climate can use multimodel ensemble (MME) methods that combine projections from individual simulation models. To predict the future changes of extreme rainfall in Iran, we examined the observations and 24 models of the Coupled Model Inter-Comparison Project Phase 6 (CMIP6) over the Middle East. We applied generalized extreme value (GEV) distribution to series of annual maximum daily precipitation (AMP1) data obtained from both of models and the observations. We also employed multivariate bias-correction under three shared socioeconomic pathway (SSP) scenarios (namely, SSP2-4.5, SSP3-7.0, and SSP5-8.5). We used a model averaging method that takes both performance and independence of model into account, which is called PI-weighting. Return levels for 20 and 50 years, as well as the return periods of the AMP1 relative to the reference years (1971–2014), were estimated for three future periods. These are period 1 (2021–2050), period 2 (2046–2075), and period 3 (2071–2100). From this study, we predict that over Iran the relative increases of 20-year return level of the AMP1 in the spatial median from the past observations to the year 2100 will be approximately 15.6% in the SSP2-4.5, 23.2% in the SSP3-7.0, and 28.7% in the SSP5-8.5 scenarios, respectively. We also realized that a 1-in-20 year (or 1-in-50 year) AMP1 observed in the reference years in Iran will likely become a 1-in-12 (1-in-26) year, a 1-in-10 (1-in-22) year, and a 1-in-9 (1-in-20) year event by 2100 under the SSP2-4.5, SSP3-7.0, and SSP5-8.5 scenarios, respectively. We project that heavy rainfall will be more prominent in the western and southwestern parts of Iran.
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Rice, Kelly, Robert Peralta, Darrin Bast, Joyce de Azavedo, and Martin J. McGavin. "Description of Staphylococcus Serine Protease (ssp) Operon in Staphylococcus aureus and Nonpolar Inactivation of sspA-Encoded Serine Protease." Infection and Immunity 69, no. 1 (January 1, 2001): 159–69. http://dx.doi.org/10.1128/iai.69.1.159-169.2001.
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ABSTRACT Signature tagged mutagenesis has recently revealed that the Ssp serine protease (V8 protease) contributes to in vivo growth and survival of Staphylococcus aureus in different infection models, and our previous work indicated that Ssp could play a role in controlling microbial adhesion. In this study, we describe an operon structure within the ssp locus of S. aureusRN6390. The ssp gene encoding V8 protease is designated assspA, and is followed by sspB, which encodes a 40.6-kDa cysteine protease, and sspC, which encodes a 12.9-kDa protein of unknown function. S. aureus SP6391 is an isogenic derivative of RN6390, in which specific loss of SspA function was achieved through a nonpolar allelic replacement mutation. In addition to losing SspA, the culture supernatant of SP6391 showed a loss of 22- to 23-kDa proteins and the appearance of a 40-kDa protein corresponding to SspB. Although the 40-kDa SspB protein could degrade denatured collagen, our data establish that this is a precursor form which is normally processed by SspA to form a mature cysteine protease. Culture supernatant of SP6391 also showed a new 42-kDa glucosaminidase and enhanced glucosaminidase activity in the 29 to 32 kDa range. Although nonpolar inactivation of sspA exerted a pleiotropic effect, S. aureus SP6391 exhibited enhanced virulence in a tissue abscess infection model relative to RN6390. Therefore, we conclude that SspA is required for maturation of SspB and plays a role in controlling autolytic activity but does not by itself exert a significant contribution to the development of tissue abscess infections.
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Beck, J. Gayle. "Leon A. Hyer, & Steven J. Sohnle Trauma among older people: Issues and treatment. Philadelphia, PA: Bruner-Routledge, 2001." Canadian Journal on Aging / La Revue canadienne du vieillissement 21, no. 2 (2002): 315–16. http://dx.doi.org/10.1017/s0714980800001586.
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RÉSUMÉL'évaluation et le traitement du syndrome de stress post-traumatique (SSPT) chez les aîné(e)s constitue un domaine quelque peu négligé de la documentation, une situation que ce livre tente de corriger. Trauma among older people: Issues and treatment est un texte réfléchi et approfondi destiné à aider le clinicien à comprendre et à gérer les problèmes posttraumatiques chez les aîné(e)s. Le travail présente une variété d'orientations théoriques, de résumés de recherche et d'expertise clinique sur la conceptualisation et le traitement du stress post-traumatique. Les auteurs prônent une vaste approche de la conceptualisation et du traitement du SSPT chez les adultes vieillissants et s'attardent à un modèle de «réadaptation» plutôt que de guérison. À ce titre, on a accordé beaucoup d'attention à la personnalité, au counseling et au pardon, dans la mesure où ces thèmes s'appliquent à l'approche intégrante du traitement mis de l'avant par les auteurs. De plus, on présente des résumés succincts et des directives d'approches courantes au traitement du SSPT, notamment pour les interventions d'exposition, les techniques de relaxation et les thérapies cognitives-comportementales.La force du document repose sur le fait que les auteurs sont bien renseignés sur les aîné(e)s. Ils présentent des idées innovatrices sur la façon dont le SSPT peut se manifester différemment chez les aîné(e)s, particulièrement chez ceux qui ont des antécédents traumatiques importants et prolongés. Il aurait été intéressant, dans ce contexte, d'en apprendre plus sur les facteurs de résilience, particulièrement à la lumière de la constatation empirique que les aîné(e)s ont recours à des stratégies souvent différentes pour faire face à un facteur de stress important. En résumé, Hyer et Sohnle ont accompli un travail magnifique dans la rédaction de Trauma among older people: Issues and treatment. Le volume est bien divisé, vise l'information du praticien sur des questions de vieillissement et de SSPT et atteint un bon équilibre entre l'information théorique et appliquée.
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Barker, Karen L., Meredith Newman, Nigel Stallard, Jose Leal, Catherine Minns Lowe, Muhammad K. Javaid, Angela Noufaily, et al. "Exercise or manual physiotherapy compared with a single session of physiotherapy for osteoporotic vertebral fracture: three-arm PROVE RCT." Health Technology Assessment 23, no. 44 (August 2019): 1–318. http://dx.doi.org/10.3310/hta23440.
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Background A total of 25,000 people in the UK have osteoporotic vertebral fracture (OVF). Evidence suggests that physiotherapy may have an important treatment role. Objective The objective was to investigate the clinical effectiveness and cost-effectiveness of two different physiotherapy programmes for people with OVF compared with a single physiotherapy session. Design This was a prospective, adaptive, multicentre, assessor-blinded randomised controlled trial (RCT) with nested qualitative and health economic studies. Setting This trial was based in 21 NHS physiotherapy departments. Participants The participants were people with symptomatic OVF. Interventions Seven sessions of either manual outpatient physiotherapy or exercise outpatient physiotherapy compared with the best practice of a 1-hour single session of physiotherapy (SSPT). Main outcome measures Outcomes were measured at 4 and 12 months. The primary outcomes were quality of life and muscle endurance, which were measured by the disease-specific QUALEFFO-41 (Quality of Life Questionnaire of the European Foundation for Osteoporosis – 41 items) and timed loaded standing (TLS) test, respectively. Secondary outcomes were (1) thoracic kyphosis angle, (2) balance, evaluated via the functional reach test (FRT), and (3) physical function, assessed via the Short Physical Performance Battery (SPPB), 6-minute walk test (6MWT), Physical Activity Scale for the Elderly, a health resource use and falls diary, and the EuroQol-5 Dimensions, five-level version. Results A total of 615 participants were enrolled, with 216, 203 and 196 randomised by a computer-generated program to exercise therapy, manual therapy and a SSPT, respectively. Baseline data were available for 613 participants, 531 (86.6%) of whom were women; the mean age of these participants was 72.14 years (standard deviation 9.09 years). Primary outcome data were obtained for 69% of participants (429/615) at 12 months: 175 in the exercise therapy arm, 181 in the manual therapy arm and 173 in the SSPT arm. Interim analysis met the criteria for all arms to remain in the study. For the primary outcomes at 12 months, there were no significant benefits over SSPT of exercise [QUALEFFO-41, difference –0.23 points, 95% confidence interval (CI) –3.20 to 1.59 points; p = 1.000; and TLS test, difference 5.77 seconds, 95% CI –4.85 to 20.46 seconds; p = 0.437] or of manual therapy (QUALEFFO-41, difference 1.35 points, 95% CI –1.76 to 2.93 points; p = 0.744; TLS test, difference 9.69 seconds (95% CI 0.09 to 24.86 seconds; p = 0.335). At 4 months, there were significant gains for both manual therapy and exercise therapy over SSPT in the TLS test in participants aged < 70 years. Exercise therapy was superior to a SSPT at 4 months in the SPPB, FRT and 6MWT and manual therapy was superior to a SSPT at 4 months in the TLS test and FRT. Neither manual therapy nor exercise therapy was cost-effective relative to a SSPT using the threshold of £20,000 per quality-adjusted life-year. There were no treatment-related serious adverse events. Conclusions This is the largest RCT to date assessing physiotherapy in participants with OVFs. At 1 year, neither treatment intervention conferred more benefit than a single 1-hour physiotherapy advice session. The focus of future work should be on the intensity and duration of interventions to determine if changes to these would demonstrate more sustained effects. Trial registration Current Controlled Trials ISRCTN49117867. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 44. See the NIHR Journals Library website for further project information.
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Michalsik, Lars Bojsen, Patrick Fuchs, and Herbert Wagner. "The Team Handball Game-Based Performance Test Is Better than the Yo-Yo Intermittent Recovery Test to Measure Match-Related Activities in Female Adult Top-Elite Field Team Handball Players." Applied Sciences 11, no. 14 (July 16, 2021): 6551. http://dx.doi.org/10.3390/app11146551.
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In team handball, suitable tests determining the match-related physical performance are essential for the planning of optimal physical training regimens. Thus, the aims of the present study were (a) to determine the relationships between the physical and physiological test results from a team handball game-based performance test (GBPT), the Yo-Yo intermittent recovery test, level 1 (Yo-Yo IR1 test) and a separate linear 30-m single sprint performance test (SSPT) in female adult top-elite field team handball players, in order to establish the significance (validity) of tests for measuring relevant elements for team handball match-play; and (b) to compare and evaluate the results from the aforementioned tests for the same players in relation to the different playing positions. Twenty-three female adult top-elite field team handball players from the Danish Premier Female Team Handball League performed the GBPT, the Yo-Yo IR1 test and the 30-m SSPT test on separate days. As main findings, significant correlations between the GBPT and the Yo-Yo IR1 test in about 1/3 of the variables were found, indicating that the Yo-Yo IR1 test is reflecting most of the locomotive match activities in female adult top-elite team handball. However, the Yo-Yo IR1 test results were not correlated to the GBPT in any of the match-related activities in the team handball GBPT that included technical playing actions such as tackles, passes, jumping and shooting during specialized movements in offence and defence. Overall, the results revealed that the GBPT is better than the Yo-Yo IR1 test to evaluate female adult top-elite field team handball players’ ability to perform physical match-related activities including both locomotive and technical playing actions executed as during competitive match-play. Similar to the Yo-Yo IR1 test, the 30-m SSPT was not correlated to any of the team handball GBPT activities, which included technical playing actions. These data suggest that the SSPT only to a certain extent can measure the individual sprint capacity of elite team handball players. In addition, unexpectedly no significant differences between the various playing positions were found neither for the GBPT, the SSPT nor the Yo-Yo IR1 test. However, several effects sizes indicated that the lack of positional differences primarily was due to the relatively small sample size in each playing position and the composition of the specific group of players. In conclusion, this study clearly indicated that team handball specific physical performance, as measured by the GBPT, and general physical performance, as measured by the Yo-Yo IR1 test and the 30-m SSPT, are different components. This must be taken in consideration when using physical test results for the planning of optimal physical training regimens in elite team handball.
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Nakajima, Koichiro, Hiromitsu Iwata, Yukiko Hattori, Kento Nomura, Shingo Hashimoto, Toshiyuki Toshito, Kensuke Hayashi, et al. "Spot Scanning Proton Therapy for Sinonasal Malignant Tumors." International Journal of Particle Therapy 8, no. 1 (June 1, 2021): 189–99. http://dx.doi.org/10.14338/ijpt-d-20-00043.1.
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Abstract Purpose Treatment of sinonasal malignant tumors is challenging, and evidence to establish a standard treatment is limited. Our objective was to evaluate the efficacy and safety of spot scanning proton therapy (SSPT) for sinonasal malignant tumors. Patients and Methods We retrospectively analyzed patients with sinonasal malignant tumors (T1-4bN0-2M0) who underwent SSPT between May 2014 and September 2019. The prescription dose was typically either 60 GyRBE in 15 fractions or 60.8 GyRBE in 16 fractions for mucosal melanoma and 70.2 GyRBE in 26 fractions for other histologic subtypes. Endpoints included local control (LC), progression-free survival, overall survival (OS), and incidence of toxicity. Prognostic factors were analyzed using the Kaplan-Meier method and log-rank test. Results Of 62 enrolled patients, the common histologic subtypes were mucosal melanoma (35%), squamous cell carcinoma (27%), adenoid cystic carcinoma (16%), and olfactory neuroblastoma (10%). Locally advanced stages were common (T3 in 42% and T4 in 53%). Treatment-naïve tumors and postsurgical recurrent tumors accounted for 73% and 27%, respectively. No patient had previous radiotherapy. The median follow-up was 17 months (range, 6-66) for all patients and 21.5 months (range, 6-66) for survivors. The 2-year LC, progression-free survival, and OS rates of all patients were 92%, 50%, and 76%, respectively. Univariate analysis revealed histology as a prognostic factor for OS, being higher in adenoid cystic carcinoma and olfactory neuroblastoma than in other tumors. Sixteen grade ≥3 late toxicities were observed in 12 patients (19%), including 11 events resulting in visual impairment; the most common was cataract. There was 1 grade 4 toxicity, and there were no grade 5 toxicities. Conclusion SSPT was well tolerated and yielded good LC for sinonasal malignant tumors. Although we consider SSPT to be a leading treatment modality, further studies are required to establish its status as a standard treatment.
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Ahmad, Freed, Shahid Mahboob, Tahsin Gulzar, Salah U. din, Tanzeela Hanif, Hifza Ahmad, and Muhammad Afzal. "RNA-SSPT: RNA Secondary Structure Prediction Tools." Bioinformation 9, no. 17 (October 16, 2013): 873–78. http://dx.doi.org/10.6026/97320630009873.
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Guerman, Anna D., Georgi Smirnov, and Maria Cecilia Pereira. "Attitude Dynamics and Stability of a Simple Solar Photon Thruster." Mathematical Problems in Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/943107.
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This paper is dedicated to the development of a model of the attitude dynamics for a nonideal Simple Solar Photon Thruster (SSPT) and to the analysis of sailcraft motions with respect to their centre of mass. Derivation of the expressions for force and torque due to solar radiation that is valid for the case, when there is a misalignment of the SSPT axis with the sun direction, is followed by study of sailcraft dynamics and stability properties. Analysis of stability shows that an ideally reflecting sail is unstable, while for a sailcraft with nonideal collector, the symmetry axis is stable with respect to the Sun direction for large variety of system parameters. The motion around symmetry axis is always unstable and requires an active stabilizer.
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El-Sabaeny, Azza, Donald R. Demuth, and Richard J. Lamont. "Regulation of Streptococcus gordonii sspB by thesspA Gene Product." Infection and Immunity 69, no. 10 (October 1, 2001): 6520–22. http://dx.doi.org/10.1128/iai.69.10.6520-6522.2001.
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ABSTRACT Streptococcus gordonii expresses two related adhesins, SspA and SspB, the genes for which are adjacent on the chromosome and are regulated independently. Although the adhesins are functionally similar, the sspA promoter is more active than that of sspB. In this study we show an additional role for SspA in the control of sspB activity. Gel shift and DNA footprinting assays demonstrate that the SspA protein binds to the sspB promoter and protects a region 233 to 264 bp upstream of the predicted −35 promoter element. The responsiveness of the sspB promoter to SspA was investigated with a promoter-cat reporter. Expression of thesspB promoter was reduced by over 60% in an SspA-deficient mutant of S. gordonii. These results indicate that expression of S. gordonii sspB is positively regulated by the sspA gene product.
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Zhang, Yongshu, Yu Lei, Angela Nobbs, Ali Khammanivong, and Mark C. Herzberg. "Inactivation of Streptococcusgordonii SspAB Alters Expression of Multiple Adhesin Genes." Infection and Immunity 73, no. 6 (June 2005): 3351–57. http://dx.doi.org/10.1128/iai.73.6.3351-3357.2005.
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ABSTRACT SspA and SspB (antigen I/II family proteins) can bind Streptococcus gordonii to other oral bacteria and also to salivary agglutinin glycoprotein, a constituent of the salivary film or pellicle that coats the tooth. To learn if SspA and SspB are essential for adhesion and initial biofilm formation on teeth, S. gordonii DL1 was incubated with saliva-coated hydroxyapatite (sHA) for 2 h in Todd-Hewitt broth with 20% saliva to develop initial biofilms. Sessile cells attached to sHA, surrounding planktonic cells, and free-growing cells were recovered separately. Free-growing cells expressed more sspA-specific mRNA and sspB-specific mRNA than sessile cells. Free-growing cells expressed the same levels of sspA and sspB as planktonic cells. Surprisingly, an SspA− SspB− mutant strain showed 2.2-fold greater biofilm formation on sHA than wild-type S. gordonii DL1. To explain this observation, we tested the hypothesis that inactivation of sspA and sspB genes altered the expression of other adhesin genes during initial biofilm formation in vitro. When compared to wild-type cells, expression of scaA and abpB was significantly up-regulated in the SspA− SspB− strain in sessile, planktonic, and free-growing cells. Consistent with this finding, ScaA antigen was also overexpressed in planktonic and free-growing SspA− SspB− cells compared to the wild type. SspA/B adhesins, therefore, were strongly suggested to be involved in the regulation of multiple adhesin genes.
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Holmes, Ann R., Christophe Gilbert, Jeremy M. Wells, and Howard F. Jenkinson. "Binding Properties of Streptococcus gordonii SspA and SspB (Antigen I/II Family) Polypeptides Expressed on the Cell Surface of Lactococcus lactis MG1363." Infection and Immunity 66, no. 10 (October 1, 1998): 4633–39. http://dx.doi.org/10.1128/iai.66.10.4633-4639.1998.
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ABSTRACT The oral bacterium Streptococcus gordonii expresses two cell wall-associated polypeptides, designated SspA (1,542 amino acid residues) and SspB (1,462 amino acid residues), that have 70% sequence identity. These polypeptides are members of the antigen I/II family of oral streptococcal adhesins and mediate the binding of streptococci to salivary glycoproteins, collagen, and other oral microorganisms such as Actinomyces naeslundii. To determine if SspA and SspB have differential binding properties, the coding sequences of the sspA and sspB genes were cloned into expression plasmid vector pTREX1-usp45LS to generate pTREX1-sspA and pTREX1-sspB, respectively, and the Ssp polypeptides were displayed on the cell surface ofLactococcus lactis MG1363. Lactococcal cells expressing similar levels of surface SspA or SspB polypeptide were then compared for their abilities to adhere to a range of antigen I/II polypeptide substrates. More than twice as many L. lactis cells expressing SspA bound to immobilized salivary agglutinin glycoprotein (SAG) as did L. lactis cells expressing SspB. In contrast, lactococci expressing SspB adhered twice as well as lactococci producing SspA to collagen type I and toCandida albicans. The binding of A. naeslundiito lactococci was only weakly enhanced by surface expression of Ssp polypeptides. L. lactis(pTREX1-sspB) cells bound in greater numbers to SAG than did Enterococcus faecalis JH2-2 cells expressing SspB from pAM401EB-5. The results suggest that SspA and SspB have markedly different binding affinities for their oral substrates and thus may function to promote site diversity in colonization by S. gordonii.
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Yang, Jianguo, Guohao Liu, and Wenjian Zheng. "Study on Hydrogen Diffusion Behavior during Welding of Heavy Plate." Materials 13, no. 17 (September 3, 2020): 3887. http://dx.doi.org/10.3390/ma13173887.
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For the multi-layer and multi-pass welding process of the heavy plate, the hydrogen diffusion behavior was numerically simulated to study the effect of solid-state phase transition (SSPT) on the hydrogen diffusion in the thickness direction, and the influence of the residual stress-induced diffusion after SSPT. The calculation results were compared with the experimental results. The comparison shows that the distribution of hydrogen concentration in the direction of thickness was in good agreement. The position with the most severe cold cracking sensitivity was located at a 20–30 mm depth from the top surface in this article. After welding, the hydrogen concentration in this position was kept at a high level for a long time under the effect of the size-constraint effect of the heavy plate and the existence of welding residual stress gradient. In addition, the SSPT reduced the residual stress level of weld metal (WM) significantly, increased that of the heat affected zone (HAZ), and the hydrogen was redistributed under the influence of stress. In the process of phase transformation, the parameters of hydrogen diffusion property of the material changed dramatically in a short time, the hydrogen diffusion coefficient increased in order of magnitude, and the solubility decreased in order of magnitude. This directly led to the upward diffusion of hydrogen in WM, and produced a self-gathering effect. For a welded joint of heavy plate, the self-gathering effect between passes was effective in the short-range and ineffective in the long-range.
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Yamada, Takahiro, Seishin Takao, Hidenori Koyano, Hideaki Nihongi, Yusuke Fujii, Shusuke Hirayama, Naoki Miyamoto, et al. "Validation of dose distribution for liver tumors treated with real-time-image gated spot-scanning proton therapy by log data based dose reconstruction." Journal of Radiation Research 62, no. 4 (May 5, 2021): 626–33. http://dx.doi.org/10.1093/jrr/rrab024.
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Abstract In spot scanning proton therapy (SSPT), the spot position relative to the target may fluctuate through tumor motion even when gating the radiation by utilizing a fiducial marker. We have established a procedure that evaluates the delivered dose distribution by utilizing log data on tumor motion and spot information. The purpose of this study is to show the reliability of the dose distributions for liver tumors treated with real-time-image gated SSPT (RGPT). In the evaluation procedure, the delivered spot information and the marker position are synchronized on the basis of log data on the timing of the spot irradiation and fluoroscopic X-ray irradiation. Then a treatment planning system reconstructs the delivered dose distribution. Dose distributions accumulated for all fractions were reconstructed for eight liver cases. The log data were acquired in all 168 fractions for all eight cases. The evaluation was performed for the values of maximum dose, minimum dose, D99, and D5–D95 for the clinical target volumes (CTVs) and mean liver dose (MLD) scaled by the prescribed dose. These dosimetric parameters were statistically compared between the planned dose distribution and the reconstructed dose distribution. The mean difference of the maximum dose was 1.3% (95% confidence interval [CI]: 0.6%—2.1%). Regarding the minimum dose, the mean difference was 0.1% (95% CI: −0.5%—0.7%). The mean differences of D99, D5–D95 and MLD were below 1%. The reliability of dose distributions for liver tumors treated with RGPT-SSPT was shown by the evaluation of the accumulated dose distributions.
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Lund, Marianne T., Gunnar Myhre, and Bjørn H. Samset. "Anthropogenic aerosol forcing under the Shared Socioeconomic Pathways." Atmospheric Chemistry and Physics 19, no. 22 (November 18, 2019): 13827–39. http://dx.doi.org/10.5194/acp-19-13827-2019.
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Abstract. Emissions of anthropogenic aerosols are expected to change drastically over the coming decades, with potentially significant climate implications. Using the most recent generation of harmonized emission scenarios, the Shared Socioeconomic Pathways (SSPs) as input to a global chemistry transport and radiative transfer model, we provide estimates of the projected future global and regional burdens and radiative forcing of anthropogenic aerosols under three contrasting pathways for air pollution levels: SSP1-1.9, SSP2-4.5 and SSP3-7.0. We find that the broader range of future air pollution emission trajectories spanned by the SSPs compared to previous scenarios translates into total aerosol forcing estimates in 2100 relative to 1750 ranging from −0.04 in SSP1-1.9 to −0.51 W m−2 in SSP3-7.0. Compared to our 1750–2015 estimate of −0.55 W m−2, this shows that, depending on the success of air pollution policies and socioeconomic development over the coming decades, aerosol radiative forcing may weaken by nearly 95 % or remain close to the preindustrial to present-day level. In all three scenarios there is a positive forcing in 2100 relative to 2015, from 0.51 in SSP1-1.9 to 0.04 W m−2 in SSP3-7.0. Results also demonstrate significant differences across regions and scenarios, especially in South Asia and Africa. While rapid weakening of the negative aerosol forcing following effective air quality policies will unmask more of the greenhouse-gas-induced global warming, slow progress on mitigating air pollution will significantly enhance the atmospheric aerosol levels and risk to human health in these regions. In either case, the resulting impacts on regional and global climate can be significant.
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Smyth, Aidan P. J., Kimberley L. Gammage, Larkin Lamarche, and Cameron Muir. "Examining University Men’s Psychobiological and Behavioral Response-Recovery Profile From a Social-Evaluative Body Image Threat." American Journal of Men's Health 14, no. 2 (March 2020): 155798832091083. http://dx.doi.org/10.1177/1557988320910831.
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Negative body image, which often results from social-evaluative body image threats, is common in young men and related to many harmful outcomes. Using social self-preservation theory (SSPT), the present study investigated the psychobiological (i.e., shame and cortisol) and behavioral (e.g., submission) response-recovery profile to a social-evaluative body image threat in university men. Participants ( N = 69; Mage = 20.80 years, SD = 1.84) were randomly assigned to a high-threat ( n = 34) or low-threat condition ( n = 35). Men in the high-threat condition reported greater post-threat body shame, had greater post-threat cortisol levels, and exhibited more shame-relevant behaviors than men in the low-threat condition. There were no significant differences between conditions for body shame or cortisol at the final post-threat time point (after resting for 30 min). These findings are consistent with SSPT and suggest that men respond to, and recover from, body image threats relatively efficiently.
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Ramakrishnan, Saminathan, Jason R. Stagno, Valentin Magidson, William F. Heinz, and Yun-Xing Wang. "A combined approach to characterize ligand-induced solid–solid phase transitions in biomacromolecular crystals." Journal of Applied Crystallography 54, no. 3 (May 9, 2021): 787–96. http://dx.doi.org/10.1107/s1600576721003137.
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Solid–solid phase transitions (SSPTs) are widespread naturally occurring phenomena. Understanding the molecular mechanisms and kinetics of SSPTs in various crystalline materials, however, has been challenging due to technical limitations. In particular, SSPTs in biomacromolecular crystals, which may involve large-scale changes and particularly complex sets of interactions, are largely unexplored, yet may have important implications for time-resolved crystallography and for developing synthetic biomaterials. The adenine riboswitch (riboA) is an RNA control element that uses ligand-induced conformational changes to regulate gene expression. Crystals of riboA, upon the addition of a ligand, undergo an SSPT from monoclinic to triclinic to orthorhombic. Here, solution atomic force microscopy (AFM) and polarized video microscopy (PVM) are used to characterize the multiple transition states throughout the SSPT in both the forward and the reverse directions. This contribution describes detailed protocols for growing crystals directly on mica or glass surfaces for AFM and PVM characterization, respectively, as well as methods for image processing and phase-transition kinetics analysis.
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Shin, Yonggwan, Yire Shin, Juyoung Hong, Maeng-Ki Kim, Young-Hwa Byun, Kyung-On Boo, Il-Ung Chung, Doo-Sun R. Park, and Jeong-Soo Park. "Future Projections and Uncertainty Assessment of Precipitation Extremes in the Korean Peninsula from the CMIP6 Ensemble with a Statistical Framework." Atmosphere 12, no. 1 (January 11, 2021): 97. http://dx.doi.org/10.3390/atmos12010097.
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Scientists occasionally predict projected changes in extreme climate using multi-model ensemble methods that combine predictions from individual simulation models. To predict future changes in precipitation extremes in the Korean peninsula, we examined the observed data and 21 models of the Coupled Model Inter-Comparison Project Phase 6 (CMIP6) over East Asia. We applied generalized extreme value distribution (GEVD) to a series of annual maximum daily precipitation (AMP1) data. Multivariate bias-corrected simulation data under three shared socioeconomic pathway (SSP) scenarios—namely, SSP2-4.5, SSP3-7.0, and SSP5-8.5—were used. We employed a model weighting method that accounts for both performance and independence (PI-weighting). In calculating the PI-weights, two shape parameters should be determined, but usually, a perfect model test method requires a considerable amount of computing time. To address this problem, we suggest simple ways for selecting two shape parameters based on the chi-square statistic and entropy. Variance decomposition was applied to quantify the uncertainty of projecting the future AMP1. Return levels spanning over 20 and 50 years, as well as the return periods relative to the reference years (1973–2010), were estimated for three overlapping periods in the future, namely, period 1 (2021–2050), period 2 (2046–2075), and period 3 (2071–2100). From these analyses, we estimated that the relative increases in the observations for the spatial median 20-year return level will be approximately 18.4% in the SSP2-4.5, 25.9% in the SSP3-7.0, and 41.7% in the SSP5-8.5 scenarios, respectively, by the end of the 21st century. We predict that severe rainfall will be more prominent in the southern and central parts of the Korean peninsula.
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Shin, Yonggwan, Yire Shin, Juyoung Hong, Maeng-Ki Kim, Young-Hwa Byun, Kyung-On Boo, Il-Ung Chung, Doo-Sun R. Park, and Jeong-Soo Park. "Future Projections and Uncertainty Assessment of Precipitation Extremes in the Korean Peninsula from the CMIP6 Ensemble with a Statistical Framework." Atmosphere 12, no. 1 (January 11, 2021): 97. http://dx.doi.org/10.3390/atmos12010097.
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Scientists occasionally predict projected changes in extreme climate using multi-model ensemble methods that combine predictions from individual simulation models. To predict future changes in precipitation extremes in the Korean peninsula, we examined the observed data and 21 models of the Coupled Model Inter-Comparison Project Phase 6 (CMIP6) over East Asia. We applied generalized extreme value distribution (GEVD) to a series of annual maximum daily precipitation (AMP1) data. Multivariate bias-corrected simulation data under three shared socioeconomic pathway (SSP) scenarios—namely, SSP2-4.5, SSP3-7.0, and SSP5-8.5—were used. We employed a model weighting method that accounts for both performance and independence (PI-weighting). In calculating the PI-weights, two shape parameters should be determined, but usually, a perfect model test method requires a considerable amount of computing time. To address this problem, we suggest simple ways for selecting two shape parameters based on the chi-square statistic and entropy. Variance decomposition was applied to quantify the uncertainty of projecting the future AMP1. Return levels spanning over 20 and 50 years, as well as the return periods relative to the reference years (1973–2010), were estimated for three overlapping periods in the future, namely, period 1 (2021–2050), period 2 (2046–2075), and period 3 (2071–2100). From these analyses, we estimated that the relative increases in the observations for the spatial median 20-year return level will be approximately 18.4% in the SSP2-4.5, 25.9% in the SSP3-7.0, and 41.7% in the SSP5-8.5 scenarios, respectively, by the end of the 21st century. We predict that severe rainfall will be more prominent in the southern and central parts of the Korean peninsula.
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Shim, Sungbo, Hyunmin Sung, Sanghoon Kwon, Jisun Kim, Jaehee Lee, Minah Sun, Jaeyoung Song, et al. "Regional Features of Long-Term Exposure to PM2.5 Air Quality over Asia under SSP Scenarios Based on CMIP6 Models." International Journal of Environmental Research and Public Health 18, no. 13 (June 25, 2021): 6817. http://dx.doi.org/10.3390/ijerph18136817.
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This study investigates changes in fine particulate matter (PM2.5) concentration and air-quality index (AQI) in Asia using nine different Coupled Model Inter-Comparison Project 6 (CMIP6) climate model ensembles from historical and future scenarios under shared socioeconomic pathways (SSPs). The results indicated that the estimated present-day PM2.5 concentrations were comparable to satellite-derived data. Overall, the PM2.5 concentrations of the analyzed regions exceeded the WHO air-quality guidelines, particularly in East Asia and South Asia. In future SSP scenarios that consider the implementation of significant air-quality controls (SSP1-2.6, SSP5-8.5) and medium air-quality controls (SSP2-4.5), the annual PM2.5 levels were predicted to substantially reduce (by 46% to around 66% of the present-day levels) in East Asia, resulting in a significant improvement in the AQI values in the mid-future. Conversely, weak air pollution controls considered in the SSP3-7.0 scenario resulted in poor AQI values in China and India. Moreover, a predicted increase in the percentage of aged populations (>65 years) in these regions, coupled with high AQI values, may increase the risk of premature deaths in the future. This study also examined the regional impact of PM2.5 mitigations on downward shortwave energy and surface air temperature. Our results revealed that, although significant air pollution controls can reduce long-term exposure to PM2.5, it may also contribute to the warming of near- and mid-future climates.
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Yaghi, A. H., T. H. Hyde, A. A. Becker, and W. Sun. "Numerical simulation of P91 pipe welding including the effects of solid-state phase transformation on residual stresses." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 221, no. 4 (October 1, 2007): 213–24. http://dx.doi.org/10.1243/14644207jmda152.
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The methodology of numerically simulating residual stresses in a welded P91 pipe section is described. The finite element (FE) method has been applied to simulate residual axial and hoop stresses generated in the weld region and heat affected zone (HAZ) of an axisymmetric 50-bead circumferentially butt-welded P91 steel pipe, with outer diameter of 145 mm and wall thickness of 50mm. The FE simulation consists of a thermal analysis which is followed by a sequentially-coupled structural analysis. Solid-state phase transformation (SSPT), which is characteristic of P91 steel during welding thermal cycles, has been modelled in the FE analysis by allowing for volumetric changes in steel and associated changes in yield stress due to austenitic and martensitic transformations. Phase transformation plasticity has also been taken into account. Preheat and interpass temperature control has been included in the modelling process. Thermally-obtained temperature contours indicate the size of the weld region, parent metal penetration, and HAZ. Residual axial and hoop stresses have been depicted through the pipe wall thickness as well as along the outer surface of the pipe. The results indicate the importance of including SSPT in the simulation of stresses during the welding of P91 steel.
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Almazroui, Mansour, Fahad Saeed, Sajjad Saeed, M. Nazrul Islam, Muhammad Ismail, Nana Ama Browne Klutse, and Muhammad Haroon Siddiqui. "Projected Change in Temperature and Precipitation Over Africa from CMIP6." Earth Systems and Environment 4, no. 3 (July 2, 2020): 455–75. http://dx.doi.org/10.1007/s41748-020-00161-x.
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Abstract We analyze data of 27 global climate models from the sixth phase of the Coupled Model Intercomparison Project (CMIP6), and examine projected changes in temperature and precipitation over the African continent during the twenty-first century. The temperature and precipitation changes are computed for two future time slices, 2030–2059 (near term) and 2070–2099 (long term), relative to the present climate (1981–2010), for the entire African continent and its eight subregions. The CMIP6 multi-model ensemble projected a continuous and significant increase in the mean annual temperature over all of Africa and its eight subregions during the twenty-first century. The mean annual temperature over Africa for the near (long)-term period is projected to increase by 1.2 °C (1.4 °C), 1.5 °C (2.3 °C), and 1.8 °C (4.4 °C) under the Shared Socioeconomic Pathways (SSPs) for weak, moderate, and strong forcing, referenced as SSP1-2.6, SSP2-4.5, and SSP5-8.5, respectively. The future warming is not uniform over Africa and varies regionally. By the end of the twenty-first century, the largest rise in mean annual temperature (5.6 °C) is projected over the Sahara, while the smallest rise (3.5 °C) is over Central East Africa, under the strong forcing SSP5-8.5 scenario. The projected boreal winter and summer temperature patterns for the twenty-first century show spatial distributions similar to the annual patterns. Uncertainty associated with projected temperature over Africa and its eight subregions increases with time and reaches a maximum by the end of the twenty-first century. On the other hand, the precipitation projections over Africa during the twenty-first century show large spatial variability and seasonal dependency. The northern and southern parts of Africa show a reduction in precipitation, while the central parts of Africa show an increase, in future climates under the three reference scenarios. For the near (long)-term periods, the area-averaged precipitation over Africa is projected to increase by 6.2 (4.8)%, 6.8 (8.5)%, and 9.5 (15.2)% under SSP1-2.6, SSP2-4.5, and SSP5-8.5, respectively. The median warming simulated by the CMIP6 model ensemble remains higher than the CMIP5 ensemble over most of Africa, reaching as high as 2.5 °C over some regions, while precipitation shows a mixed spatial pattern.
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Sun, Lili, Huijuan Cui, and Quansheng Ge. "Driving Factors and Future Prediction of Carbon Emissions in the ‘Belt and Road Initiative’ Countries." Energies 14, no. 17 (September 1, 2021): 5455. http://dx.doi.org/10.3390/en14175455.
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‘Belt and Road Initiative’ (B&R) countries play critical roles in mitigating global carbon emission under the Paris agreement, but their driving factors and feasibility to reduce carbon emissions remain unclear. This paper aims to identify the main driving factors (MDFs) behind carbon emissions and predict the future emissions trajectories of the B&R countries under different social-economic pathways based on the extended STIRPAT (stochastic impacts by regression on population, affluence, and technology) model. The empirical results indicate that GDP per capita and energy consumption structure are the MDFs that promote carbon emission, while energy intensity improvement is the MDF that inhibits carbon emission. Population, as another MDF, has a dual impact across countries. The carbon emissions in all B&R countries are predicted to increase from SSP1 to SSP3, but emissions trajectories vary across countries. Under the SSP1 scenario, carbon emissions in over 60% of B&R countries can peak or decline, and the aggregated peak emissions will amount to 21.97 Gt in 2030. Under the SSP2 scenario, about half of the countries can peak or decline, while their peak emissions and peak time are both higher and later than SSP1, the highest emission of 25.35 Gt is observed in 2050. Conversely, over 65% of B&R countries are incapable of either peaking or declining under the SSP3 scenario, with the highest aggregated emission of 33.10 Gt in 2050. It is further suggested that decline of carbon emission occurs when the inhibiting effects of energy intensity exceed the positive impacts of other MDFs in most B&R countries.
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Furuya, Wilson Massamitu, Lilian Carolina Rosa Silva, Patrícia Ribeiro Neves, Daniele Botaro, Carmino Hayashi, Antônio Cláudio Furlan, and Vivian Gomes dos Santos. "Coeficientes de digestibilidade aparente da energia e proteína da silagem de sorgo com alto e baixo tanino pela tilápia do nilo (Oreochromis niloticus)." Ciência Rural 34, no. 4 (August 2004): 1213–17. http://dx.doi.org/10.1590/s0103-84782004000400038.
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Este estudo foi realizado para determinar o coeficiente de digestibilidade aparente (CDA) da energia bruta e proteína bruta da silagem de sorgo de baixo tanino (SSBT) e da silagem de sorgo de alto tanino (SSAT) para a tilápia do Nilo (Oreochromis niloticus). A ração referência foi misturada aos ingredientes-teste na proporção de 60:40. Os peixes (53,26 ± 12,94g) foram alimentados até a saciedade aparente e as fezes foram coletadas após sedimentação. A fibra em detergente neutro foi utilizada como indicador endógeno. Os CDA da energia bruta e proteína bruta da SSBT e SSAT variaram entre 70,17 e 68,37% e 84,94 e 82,40%, respectivamente. Os valores de energia digestível foram de 3049,81 e 2954,74kcal kg-1 para SSBT e SSAT, respectivamente. A SSBT apresentou valores significa-tivamente (P<0,05) maiores de energia e proteína digestíveis em relação ao SSAT. Os resultados indicaram que a tilápia do Nilo pode utilizar a energia bruta e proteína bruta da silagem de sorgo eficientemente.
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Almazroui, Mansour, Fahad Saeed, Sajjad Saeed, Muhammad Ismail, Muhammad Azhar Ehsan, M. Nazrul Islam, Muhammad Adnan Abid, et al. "Projected Changes in Climate Extremes Using CMIP6 Simulations Over SREX Regions." Earth Systems and Environment 5, no. 3 (August 23, 2021): 481–97. http://dx.doi.org/10.1007/s41748-021-00250-5.
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AbstractThis paper presents projected changes in extreme temperature and precipitation events by using Coupled Model Intercomparison Project phase 6 (CMIP6) data for mid-century (2036–2065) and end-century (2070–2099) periods with respect to the reference period (1985–2014). Four indices namely, Annual maximum of maximum temperature (TXx), Extreme heat wave days frequency (HWFI), Annual maximum consecutive 5-day precipitation (RX5day), and Consecutive Dry Days (CDD) were investigated under four socioeconomic scenarios (SSP1-2.6; SSP2-4.5; SSP3-7.0; SSP5-8.5) over the entire globe and its 26 Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX) regions. The projections show an increase in intensity and frequency of hot temperature and precipitation extremes over land. The intensity of the hottest days (as measured by TXx) is projected to increase more in extratropical regions than in the tropics, while the frequency of extremely hot days (as measured by HWFI) is projected to increase more in the tropics. Drought frequency (as measured by CDD) is projected to increase more over Brazil, the Mediterranean, South Africa, and Australia. Meanwhile, the Asian monsoon regions (i.e., South Asia, East Asia, and Southeast Asia) become more prone to extreme flash flooding events later in the twenty-first century as shown by the higher RX5day index projections. The projected changes in extremes reveal large spatial variability within each SREX region. The spatial variability of the studied extreme events increases with increasing greenhouse gas concentration (GHG) and is higher at the end of the twenty-first century. The projected change in the extremes and the pattern of their spatial variability is minimum under the low-emission scenario SSP1-2.6. Our results indicate that an increased concentration of GHG leads to substantial increases in the extremes and their intensities. Hence, limiting CO2 emissions could substantially limit the risks associated with increases in extreme events in the twenty-first century.
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Meinshausen, Malte, Zebedee R. J. Nicholls, Jared Lewis, Matthew J. Gidden, Elisabeth Vogel, Mandy Freund, Urs Beyerle, et al. "The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500." Geoscientific Model Development 13, no. 8 (August 13, 2020): 3571–605. http://dx.doi.org/10.5194/gmd-13-3571-2020.
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Abstract. Anthropogenic increases in atmospheric greenhouse gas concentrations are the main driver of current and future climate change. The integrated assessment community has quantified anthropogenic emissions for the shared socio-economic pathway (SSP) scenarios, each of which represents a different future socio-economic projection and political environment. Here, we provide the greenhouse gas concentrations for these SSP scenarios – using the reduced-complexity climate–carbon-cycle model MAGICC7.0. We extend historical, observationally based concentration data with SSP concentration projections from 2015 to 2500 for 43 greenhouse gases with monthly and latitudinal resolution. CO2 concentrations by 2100 range from 393 to 1135 ppm for the lowest (SSP1-1.9) and highest (SSP5-8.5) emission scenarios, respectively. We also provide the concentration extensions beyond 2100 based on assumptions regarding the trajectories of fossil fuels and land use change emissions, net negative emissions, and the fraction of non-CO2 emissions. By 2150, CO2 concentrations in the lowest emission scenario are approximately 350 ppm and approximately plateau at that level until 2500, whereas the highest fossil-fuel-driven scenario projects CO2 concentrations of 1737 ppm and reaches concentrations beyond 2000 ppm by 2250. We estimate that the share of CO2 in the total radiative forcing contribution of all considered 43 long-lived greenhouse gases increases from 66 % for the present day to roughly 68 % to 85 % by the time of maximum forcing in the 21st century. For this estimation, we updated simple radiative forcing parameterizations that reflect the Oslo Line-By-Line model results. In comparison to the representative concentration pathways (RCPs), the five main SSPs (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) are more evenly spaced and extend to lower 2100 radiative forcing and temperatures. Performing two pairs of six-member historical ensembles with CESM1.2.2, we estimate the effect on surface air temperatures of applying latitudinally and seasonally resolved GHG concentrations. We find that the ensemble differences in the March–April–May (MAM) season provide a regional warming in higher northern latitudes of up to 0.4 K over the historical period, latitudinally averaged of about 0.1 K, which we estimate to be comparable to the upper bound (∼5 % level) of natural variability. In comparison to the comparatively straight line of the last 2000 years, the greenhouse gas concentrations since the onset of the industrial period and this studies' projections over the next 100 to 500 years unequivocally depict a “hockey-stick” upwards shape. The SSP concentration time series derived in this study provide a harmonized set of input assumptions for long-term climate science analysis; they also provide an indication of the wide set of futures that societal developments and policy implementations can lead to – ranging from multiple degrees of future warming on the one side to approximately 1.5 ∘C warming on the other.
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Moeller, Ralf, Peter Setlow, Günther Reitz, and Wayne L. Nicholson. "Roles of Small, Acid-Soluble Spore Proteins and Core Water Content in Survival of Bacillus subtilis Spores Exposed to Environmental Solar UV Radiation." Applied and Environmental Microbiology 75, no. 16 (June 19, 2009): 5202–8. http://dx.doi.org/10.1128/aem.00789-09.
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ABSTRACT Spores of Bacillus subtilis contain a number of small, acid-soluble spore proteins (SASP) which comprise up to 20% of total spore core protein. The multiple α/β-type SASP have been shown to confer resistance to UV radiation, heat, peroxides, and other sporicidal treatments. In this study, SASP-defective mutants of B. subtilis and spores deficient in dacB, a mutation leading to an increased core water content, were used to study the relative contributions of SASP and increased core water content to spore resistance to germicidal 254-nm and simulated environmental UV exposure (280 to 400 nm, 290 to 400 nm, and 320 to 400 nm). Spores of strains carrying mutations in sspA, sspB, and both sspA and sspB (lacking the major SASP-α and/or SASP-β) were significantly more sensitive to 254-nm and all polychromatic UV exposures, whereas the UV resistance of spores of the sspE strain (lacking SASP-γ) was essentially identical to that of the wild type. Spores of the dacB-defective strain were as resistant to 254-nm UV-C radiation as wild-type spores. However, spores of the dacB strain were significantly more sensitive than wild-type spores to environmental UV treatments of >280 nm. Air-dried spores of the dacB mutant strain had a significantly higher water content than air-dried wild-type spores. Our results indicate that α/β-type SASP and decreased spore core water content play an essential role in spore resistance to environmentally relevant UV wavelengths whereas SASP-γ does not.
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Srikannathasan, Velupillai, Grant English, Nhat Khai Bui, Katharina Trunk, Patrick E. F. O'Rourke, Vincenzo A. Rao, Waldemar Vollmer, Sarah J. Coulthurst, and William N. Hunter. "Structural basis for type VI secreted peptidoglycanDL-endopeptidase function, specificity and neutralization inSerratia marcescens." Acta Crystallographica Section D Biological Crystallography 69, no. 12 (November 19, 2013): 2468–82. http://dx.doi.org/10.1107/s0907444913022725.
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Some Gram-negative bacteria target their competitors by exploiting the type VI secretion system to extrude toxic effector proteins. To prevent self-harm, these bacteria also produce highly specific immunity proteins that neutralize these antagonistic effectors. Here, the peptidoglycan endopeptidase specificity of two type VI secretion-system-associated effectors fromSerratia marcescensis characterized. These small secreted proteins, Ssp1 and Ssp2, cleave between γ-D-glutamic acid and L-meso-diaminopimelic acid with different specificities. Ssp2 degrades the acceptor part of cross-linked tetratetrapeptides. Ssp1 displays greater promiscuity and cleaves monomeric tripeptides, tetrapeptides and pentapeptides and dimeric tetratetra and tetrapenta muropeptides on both the acceptor and donor strands. Functional assays confirm the identity of a catalytic cysteine in these endopeptidases and crystal structures provide information on the structure–activity relationships of Ssp1 and, by comparison, of related effectors. Functional assays also reveal that neutralization of these effectors by their cognate immunity proteins, which are called resistance-associated proteins (Raps), contributes an essential role to cell fitness. The structures of two immunity proteins, Rap1a and Rap2a, responsible for the neutralization of Ssp1 and Ssp2-like endopeptidases, respectively, revealed two distinct folds, with that of Rap1a not having previously been observed. The structure of the Ssp1–Rap1a complex revealed a tightly bound heteromeric assembly with two effector molecules flanking a Rap1a dimer. A highly effective steric block of the Ssp1 active site forms the basis of effector neutralization. Comparisons with Ssp2–Rap2a orthologues suggest that the specificity of these immunity proteins for neutralizing effectors is fold-dependent and that in cases where the fold is conserved sequence differences contribute to the specificity of effector–immunity protein interactions.
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Tabari, Hossein, Santiago Mendoza Paz, Daan Buekenhout, and Patrick Willems. "Comparison of statistical downscaling methods for climate change impact analysis on precipitation-driven drought." Hydrology and Earth System Sciences 25, no. 6 (June 21, 2021): 3493–517. http://dx.doi.org/10.5194/hess-25-3493-2021.
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Abstract. General circulation models (GCMs) are the primary tools for evaluating the possible impacts of climate change; however, their results are coarse in temporal and spatial dimensions. In addition, they often show systematic biases compared to observations. Downscaling and bias correction of climate model outputs is thus required for local applications. Apart from the computationally intensive strategy of dynamical downscaling, statistical downscaling offers a relatively straightforward solution by establishing relationships between small- and large-scale variables. This study compares four statistical downscaling methods of bias correction (BC), the change factor of mean (CFM), quantile perturbation (QP) and an event-based weather generator (WG) to assess climate change impact on drought by the end of the 21st century (2071–2100) relative to a baseline period of 1971–2000 for the weather station of Uccle located in Belgium. A set of drought-related aspects is analysed, i.e. dry day frequency, dry spell duration and total precipitation. The downscaling is applied to a 28-member ensemble of Coupled Model Intercomparison Project Phase 6 (CMIP6) GCMs, each forced by four future scenarios of SSP1–2.6, SSP2–4.5, SSP3–7.0 and SSP5–8.5. A 25-member ensemble of CanESM5 GCM is also used to assess the significance of the climate change signals in comparison to the internal variability in the climate. A performance comparison of the downscaling methods reveals that the QP method outperforms the others in reproducing the magnitude and monthly pattern of the observed indicators. While all methods show a good agreement on downscaling total precipitation, their results differ quite largely for the frequency and length of dry spells. Using the downscaling methods, dry day frequency is projected to increase significantly in the summer months, with a relative change of up to 19 % for SSP5–8.5. At the same time, total precipitation is projected to decrease significantly by up to 33 % in these months. Total precipitation also significantly increases in winter, as it is driven by a significant intensification of extreme precipitation rather than a dry day frequency change. Lastly, extreme dry spells are projected to increase in length by up to 9 %.
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Almazroui, Mansour, M. Nazrul Islam, Sajjad Saeed, Fahad Saeed, and Muhammad Ismail. "Future Changes in Climate over the Arabian Peninsula based on CMIP6 Multimodel Simulations." Earth Systems and Environment 4, no. 4 (November 11, 2020): 611–30. http://dx.doi.org/10.1007/s41748-020-00183-5.
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AbstractThis paper presents the changes in projected temperature and precipitation over the Arabian Peninsula for the twenty-first century using the Coupled Model Intercomparison Project phase 6 (CMIP6) dataset. The changes are obtained by analyzing the multimodel ensemble from 31 CMIP6 models for the near (2030–2059) and far (2070–2099) future periods, with reference to the base period 1981–2010, under three future Shared Socioeconomic Pathways (SSPs). Observations show that the annual temperature is rising at the rate of 0.63 ˚C decade–1 (significant at the 99% confidence level), while annual precipitation is decreasing at the rate of 6.3 mm decade–1 (significant at the 90% confidence level), averaged over Saudi Arabia. For the near (far) future period, the 66% likely ranges of annual-averaged temperature is projected to increase by 1.2–1.9 (1.2–2.1) ˚C, 1.4–2.1 (2.3–3.4) ˚C, and 1.8–2.7 (4.1–5.8) ˚C under SSP1–2.6, SSP2–4.5, and SSP5–8.5, respectively. Higher warming is projected in the summer than in the winter, while the Northern Arabian Peninsula (NAP) is projected to warm more than Southern Arabian Peninsula (SAP), by the end of the twenty-first century. For precipitation, a dipole-like pattern is found, with a robust increase in annual mean precipitation over the SAP, and a decrease over the NAP. The 66% likely ranges of annual-averaged precipitation over the whole Arabian Peninsula is projected to change by 5 to 28 (–3 to 29) %, 5 to 31 (4 to 49) %, and 1 to 38 (12 to 107) % under SSP1–2.6, SSP2–4.5, and SSP5–8.5, respectively, in the near (far) future. Overall, the full ranges in CMIP6 remain higher than the CMIP5 models, which points towards a higher climate sensitivity of some of the CMIP6 climate models to greenhouse gas (GHG) emissions as compared to the CMIP5. The CMIP6 dataset confirmed previous findings of changes in future climate over the Arabian Peninsula based on CMIP3 and CMIP5 datasets. The results presented in this study will be useful for impact studies, and ultimately in devising future policies for adaptation in the region.
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Demuth, Donald R., and Douglas C. Irvine. "Structural and Functional Variation within the Alanine-Rich Repetitive Domain of Streptococcal Antigen I/II." Infection and Immunity 70, no. 11 (November 2002): 6389–98. http://dx.doi.org/10.1128/iai.70.11.6389-6398.2002.
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ABSTRACT Members of the antigen I/II family of cell surface proteins are highly conserved, multifunctional adhesins that mediate interactions of oral streptococci with other oral bacteria, with cell matrix proteins (e.g., type I collagen), and with salivary glycoproteins, e.g., gp340. The interaction of gp340 (formerly designated salivary agglutinin) with Streptococcus mutans requires an alanine-rich repetitive domain (A region) of antigen I/II that is highly conserved in all members of this family of proteins. In this report, we show that the A regions from the two Streptococcus gordonii M5 antigen I/II proteins (SspA and SspB) interact differently with the salivary gp340 glycoprotein and appear to be structurally distinct. Recombinant polypeptides encompassing the A region of SspA or from a highly related S. mutans antigen I/II protein (SpaP) competitively inhibited the interaction of gp340 with intact S. gordonii and S. mutans cells, respectively. In contrast, an A region polypeptide from SspB was inactive, and furthermore, it did not bind to purified gp340 in vitro. Circular dichroism spectra suggested that all three polypeptides were highly α-helical and may form coiled-coil structures. However, the A region of SspB underwent a conformational change and exhibited reduced α-helical structure at pH 8.5, whereas the A region polypeptides from SspA and SpaP were relatively stable under these conditions. Melt curves also indicated that at physiological pH, the A region of SspB lost α-helical structure more rapidly than that of SspA or SpaP when the temperature was increased from 10 to 40°C. Furthermore, the SspB A region polypeptide denatured completely at a temperature that was 7 to 9°C lower than that required for the A region polypeptide of SspA or SpaP. The full-length SspB protein and the three A region peptides migrated in native gel electrophoresis and column chromatography with apparent molecular masses that were approximately 2- to 2.5-fold greater than their predicted molecular masses. However, sedimentation equilibrium ultracentrifugation data showed that the A region peptides sedimented as monomers, suggesting that the peptides may form nonglobular intramolecular coiled-coil structures under the experimental conditions used. Taken together, our results suggest that the A region of SspB is less stable than the corresponding A regions of SspA and SpaP and that this structural difference may explain, at least in part, the functional variation observed in their interactions with salivary gp340.
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Egland, Paul G., Laurence D. Dû, and Paul E. Kolenbrander. "Identification of Independent Streptococcus gordonii SspA and SspB Functions in Coaggregation withActinomyces naeslundii." Infection and Immunity 69, no. 12 (December 1, 2001): 7512–16. http://dx.doi.org/10.1128/iai.69.12.7512-7516.2001.
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ABSTRACT The initial stages of dental plaque formation involve the adherence of early colonizing organisms such as Streptococcus gordonii and Actinomyces naeslundii to the saliva-coated tooth surface and to each other. The S. gordonii surface proteins SspA and SspB are known to play a role in adherence to salivary proteins and mediate coaggregation with other bacteria. Coaggregation is the adhesin receptor-mediated interaction between genetically distinct cell types and appears to be ubiquitous among oral isolates. To define the function of SspA and SspB separately on the surface of their natural host, we constructed and analyzed the coaggregation properties of an isogenicsspB mutant of S. gordonii DL1, ansspAB double mutant, and a previously describedsspA mutant. A. naeslundii strains have been previously classified into six coaggregation groups based on the nature of their coaggregations with S. gordonii DL1 and other oral streptococci. Coaggregation assays with thesspA and sspB mutants showed that SspA and SspB are the streptococcal proteins primarily responsible for defining these coaggregation groups and, thus, are highly significant in the establishment of early dental plaque. SspA exhibited two coaggregation-specific functions. It participated in lactose-inhibitable and -noninhibitable interactions, while SspB mediated only lactose-noninhibitable coaggregations. Accordingly, thesspAB double mutant lacked these functions and allowed us to detect a third coaggregation interaction with one of these organisms. These proteins may play an important role in development ofS. gordonii-A. naeslundii communities in early dental plaque. Understanding these adhesin proteins will aid investigations of complex microbial communities that characterize periodontal diseases.
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Nerber, Hailee N., and Joseph A. Sorg. "The small acid-soluble proteins of Clostridioides difficile are important for UV resistance and serve as a check point for sporulation." PLOS Pathogens 17, no. 9 (September 8, 2021): e1009516. http://dx.doi.org/10.1371/journal.ppat.1009516.
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Clostridioides difficile is a nosocomial pathogen which causes severe diarrhea and colonic inflammation. C. difficile causes disease in susceptible patients when endospores germinate into the toxin-producing vegetative form. The action of these toxins results in diarrhea and the spread of spores into the hospital and healthcare environments. Thus, the destruction of spores is imperative to prevent disease transmission between patients. However, spores are resilient and survive extreme temperatures, chemical exposure, and UV treatment. This makes their elimination from the environment difficult and perpetuates their spread between patients. In the model spore-forming organism, Bacillus subtilis, the small acid-soluble proteins (SASPs) contribute to these resistances. The SASPs are a family of small proteins found in all endospore-forming organisms, C. difficile included. Although these proteins have high sequence similarity between organisms, the role(s) of the proteins differ. Here, we investigated the role of the main α/β SASPs, SspA and SspB, and two annotated putative SASPs, CDR20291_1130 and CDR20291_3080, in protecting C. difficile spores from environmental insults. We found that SspA is necessary for conferring spore UV resistance, SspB minorly contributes, and the annotated putative SASPs do not contribute to UV resistance. In addition, the SASPs minorly contribute to the resistance of nitrous acid. Surprisingly, the combined deletion of sspA and sspB prevented spore formation. Overall, our data indicate that UV resistance of C. difficile spores is dependent on SspA and that SspA and SspB regulate/serve as a checkpoint for spore formation, a previously unreported function of SASPs.
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Shaw, Lindsey N., Ewa Golonka, Grzegorz Szmyd, Simon J. Foster, James Travis, and Jan Potempa. "Cytoplasmic Control of Premature Activation of a Secreted Protease Zymogen: Deletion of Staphostatin B (SspC) in Staphylococcus aureus 8325-4 Yields a Profound Pleiotropic Phenotype." Journal of Bacteriology 187, no. 5 (March 1, 2005): 1751–62. http://dx.doi.org/10.1128/jb.187.5.1751-1762.2005.
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ABSTRACT The cytoplasmic protein SspC of Staphylococcus aureus, referred to as staphostatin B, is a very specific, tightly binding inhibitor of the secreted protease staphopain B (SspB). SspC is hypothesized to protect intracellular proteins against proteolytic damage by prematurely folded and activated staphopain B (M. Rzychon, A. Sabat, K. Kosowska, J. Potempa, and A. Dubin, Mol. Microbiol. 49:1051-1066, 2003). Here we provide evidence that elimination of intracellular staphopain B activity is indeed the function of SspC. An isogenic sspC mutant of S. aureus 8325-4 exhibits a wide range of striking pleiotropic alterations in phenotype, which distinguish it from the parent. These changes include a defect in growth, a less structured peptidoglycan layer within the cell envelope, severely decreased autolytic activity, resistance to lysis by S. aureus phages, extensively diminished sensitivity to lysis by lysostaphin, the ability to form a biofilm, and a total lack of extracellular proteins secreted into the growth media. The same phenotype was also engineered by introduction of sspB into an 8325-4 sspBC mutant. In contrast, sspC inactivation in the SH1000 strain did not yield any significant changes in the mutant phenotype, apparently due to strongly reduced expression of sspB in the sigma B-positive background. The exact pathway by which these diverse aberrations are exerted in 8325-4 is unknown, but it is apparent that a very small amount of staphopain B (less than 20 ng per 200 μg of cell proteins) is sufficient to bring about these widespread changes. It is proposed that the effects observed are modulated through the proteolytic degradation of several cytoplasmic proteins within cells lacking the inhibitor. Seemingly, some of these proteins may play a role in protein secretion; hence, their proteolytic inactivation by SspB has pleiotropic effects on the SspC-deficient mutant.
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Jo, Duseong S., Alma Hodzic, Louisa K. Emmons, Simone Tilmes, Rebecca H. Schwantes, Michael J. Mills, Pedro Campuzano-Jost, et al. "Future changes in isoprene-epoxydiol-derived secondary organic aerosol (IEPOX SOA) under the Shared Socioeconomic Pathways: the importance of physicochemical dependency." Atmospheric Chemistry and Physics 21, no. 5 (March 5, 2021): 3395–425. http://dx.doi.org/10.5194/acp-21-3395-2021.
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Abstract. Secondary organic aerosol (SOA) is a dominant contributor of fine particulate matter in the atmosphere, but the complexity of SOA formation chemistry hinders the accurate representation of SOA in models. Volatility-based SOA parameterizations have been adopted in many recent chemistry modeling studies and have shown a reasonable performance compared to observations. However, assumptions made in these empirical parameterizations can lead to substantial errors when applied to future climatic conditions as they do not include the mechanistic understanding of processes but are rather fitted to laboratory studies of SOA formation. This is particularly the case for SOA derived from isoprene epoxydiols (IEPOX SOA), for which we have a higher level of understanding of the fundamental processes than is currently parameterized in most models. We predict future SOA concentrations using an explicit mechanism and compare the predictions with the empirical parameterization based on the volatility basis set (VBS) approach. We then use the Community Earth System Model 2 (CESM2.1.0) with detailed isoprene chemistry and reactive uptake processes for the middle and end of the 21st century under four Shared Socioeconomic Pathways (SSPs): SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5. With the explicit chemical mechanism, we find that IEPOX SOA is predicted to increase on average under all future SSP scenarios but with some variability in the results depending on regions and the scenario chosen. Isoprene emissions are the main driver of IEPOX SOA changes in the future climate, but the IEPOX SOA yield from isoprene emissions also changes by up to 50 % depending on the SSP scenario, in particular due to different sulfur emissions. We conduct sensitivity simulations with and without CO2 inhibition of isoprene emissions that is highly uncertain, which results in factor of 2 differences in the predicted IEPOX SOA global burden, especially for the high-CO2 scenarios (SSP3–7.0 and SSP5–8.5). Aerosol pH also plays a critical role in the IEPOX SOA formation rate, requiring accurate calculation of aerosol pH in chemistry models. On the other hand, isoprene SOA calculated with the VBS scheme predicts a nearly constant SOA yield from isoprene emissions across all SSP scenarios; as a result, it mostly follows isoprene emissions regardless of region and scenario. This is because the VBS scheme does not consider heterogeneous chemistry; in other words, there is no dependency on aerosol properties. The discrepancy between the explicit mechanism and VBS parameterization in this study is likely to occur for other SOA components as well, which may also have dependencies that cannot be captured by VBS parameterizations. This study highlights the need for more explicit chemistry or for parameterizations that capture the dependence on key physicochemical drivers when predicting SOA concentrations for climate studies.
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Deng, Hao, Wei Hua, and Guangzhou Fan. "Evaluation and Projection of Near-Surface Wind Speed over China Based on CMIP6 Models." Atmosphere 12, no. 8 (August 18, 2021): 1062. http://dx.doi.org/10.3390/atmos12081062.
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The characteristics of near-surface wind speed (NWS) are important to the study of dust storms, evapotranspiration, heavy rainfall, air pollution, and wind energy development. This study evaluated the performance of 30 models of the Coupled Model Intercomparison Project Phase 6 (CMIP6) through comparison with observational NWS data acquired in China during a historical period (1975–2014), and projected future changes in NWS under three scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) based on an optimal multi-model ensemble. Results showed that most models reproduced the spatial pattern of NWS for all seasons and the annual mean, although the models generally overestimated NWS magnitude. All models tended to underestimate the trends of decline of NWS for all seasons and the annual mean. On the basis of a comprehensive ranking index, the KIOST-ESM, CNRM-ESM2-1, HadGEM3-GC31-LL, CMCC-CM2-SR5, and KACE-1-0-G models were ranked as the five best-performing models. In the projections of future change, nationally averaged NWS for all months was weaker than in the historical period, and the trends decreased markedly under all the different scenarios except the winter time series under SSP2-4.5. Additionally, the projected NWS over most regions of China weakened in both the early period (2021–2060) and the later period (2061–2100).