Warming amplification over the Arctic Pole (AP hereafter) and Third Pole (Tibetan Plateau, TP hereafter) can trigger a series of climate responses and have global consequences. Arctic amplification ...(AA) and Tibetan amplification (TA) are the most significant characteristics of climate change patterns over the two Poles. In this study, trends, mechanisms and consequences of both AA and TA are compared. Based on ERA5 reanalysis during 1979–2020, both AP and TP have undergone significant warming with an annual rate of 0.72 °C/decade and 0.34 °C/decade respectively, which exceeds the rates for the Northern Hemisphere (0.29 °C/decade) and the global means (0.19 °C/decade) over the same period. Based on 22 Coupled Model Intercomparison Project Phase 6 models, AA over the AP is warming at a rate almost four times than the global means and twice as fast over the TP. Although both AA and TA are projected to continue in the future, currently there is no consensus on the dominant mechanisms for AA or TA over the two Poles. Proposed mechanisms of AA can be divided into two types: local climate factors (sea ice-albedo feedback, Planck feedback, temperature gradient feedback, cloud feedback, and water vapor feedback); and poleward heat and moisture transport from lower latitudes (atmospheric circulation effect, ocean circulation effect, and modulation of Pacific and Atlantic SST). Consequences of AA include decline of sea ice cover, retreat of the Greenland ice sheet, permafrost degradation, accelerated disturbances in marine and terrestrial ecosystems, and influences on extreme climate events at lower latitudes. Anthropogenic greenhouse gas emission, snow/ice-albedo feedback, cloud-radiation interactions, water vapor and radiative flux feedbacks, local forcing and feedback processes, land use changes and reduction in total ozone, are generally considered to be the main mechanisms causing TA. TA has caused significant change within the atmosphere and cryosphere over the TP and its surroundings, such as changes in climate extremes, snow cover, the retreat of glaciers, and permafrost degradation. Similarities and differences of warming amplifications over the two Poles are proposed, and the relative contribution of each mechanism to the warming amplifications and how the specific consequences may compare over the two Poles remain unclear and under continuing investigation.
Virtual coupling technology was recently proposed in railways, which separates trains by a relative braking distance (or even shorter distance) and moves trains synchronously to increase capacity at ...bottlenecks. This study proposes a real‐time cooperative train trajectory planning algorithm for coordinating train movements under virtual coupling by considering stochastic initial delays. The algorithm uses mixed‐integer programming models to estimate the delay propagation among trains, detect feasible coupled‐running locations, and optimize the trajectories of the two trains such that they coordinate their speeds to achieve energy‐efficient, punctual movements, as well as a safe coupled‐running process. A robust optimization method is proposed to capture the stochastic delays as an uncertainty set, which is reformulated to its dual problem. Case studies of planning train trajectories for the classical virtual‐coupling scenario suggest that (1) the coupled‐running distance is greatly affected by the coordination of train timetables, delays, and safe separation constraints at switches; (2) the coordination of train movements for a coupled‐running process imposes extra energy costs; and (3) the proposed method can detect feasible coupled‐running locations and produce cooperative speed profiles in short computational times.
This study proposes a real‐time cooperative train trajectory planning algorithm for coordinating train movements under virtual coupling by considering stochastic initial delays. The algorithm uses mixed‐ integer programming models to estimate the delay propagation among trains, detect feasible coupled‐ running locations, and optimize the trajectories of the two trains such that they coordinate their speeds to achieve energy‐efficient, punctual movements, as well as a safe coupled‐running process.
Global large-scale urbanization and climate change have become indisputable scientific facts yet are unresolved issues, and are a common concern for mankind. The relationship between these two topics ...is unclear and it is not known how to deal appropriately at the scientific level with climate change in the process of urbanization. Further exploration of the science, management and practice, are needed to achieve global and regional sustainable development. This paper first considers the basic facts concerning mass urbanization and climate change and summarizes the interactions and possible mechanisms of urbanization and climate change. Urbanization leads to the heat island effect, an uneven distribution of precipitation and extreme weather, together with a local-regional-global multi-scale superposition effect, which aggravates the consequences of global climate change. The impact of climate change on urbanization is mainly manifested in aspects such as changes of energy consumption, mortality, and the spread of infectious diseases, sea level rise, extreme weather damage to infrastructure, and water shortages. This paper also briefly reviews relevant international research programs and action coalitions and puts forward an analysis framework of multi-dimensional sustainable urbanization which can adapt to and mitigate climate change, from the perspective of the four key dimensions—population, land use, economy, and society. It is imperative that we strengthen the interdisciplinary activities involving the natural and social sciences, take urbanization and other human activities into consideration of the land — atmosphere system, and explore the human-land-atmosphere coupling process. The adaptation and mitigation from the perspective of human activities, as represented by urbanization, might be the most critical and realistic way to deal with climate change.
Endometrioid Endometrial Cancer (EEC) is the main subtype of endometrial cancer. In our study, we demonstrated that SPTBN2 was significantly overexpressed in EEC tissues. Upregulated SPTBN2 ...expression was positively associated with poor prognosis. In addition, we testified that SPTBN2 knockdown significantly inhibited the proliferation, migration, and invasion of EEC cells. Moreover, we found SPTBN2 could interact with CLDN4 to promote endometrial cancer metastasis via PI3K/AKT pathway. Then we further demonstrated that CLDN4 is upregulated in EEC and promotes EEC metastasis. CLDN4 overexpression could partially reversed the decrease in cell migration and invasion caused by SPTBN2 downregulation. In addition, we confirmed that SPTBN2 was a target of miR-424-5p, which plays a tumor suppressor in endometrial cancer. Rescue experiments showed that inhibition of SPTBN2 could partially reverse the effect of miR-424-5p in EEC. In conclusion, we demonstrated that by acting as a significant target of miR-424-5p, SPTBN2 could interact with CLDN4 to promote endometrial cancer metastasis via PI3K/AKT pathway in EEC. Our study revealed the prognostic and metastatic effects of SPTBN2 in EEC, suggesting that SPTBN2 could serve as a prognostic biomarker and a target for metastasis therapy.
PDIA6 have been reported to be involved in a variety of cancers, however, the underlying role in endometrial cancer is still unclear. In this study, we aimed to study the function of PDIA6 in ...endometrial cancer. Firstly, we verified that PDIA6 was significantly upregulated in endometrial cancer, which was correlated with the progression of endometrial cancer patients. Furthermore, we identified PDIA6 significantly altered the ability of endometrial cancer cells to proliferate and metastasize. In addition, our result illustrated the oncogene effects of PDIA6 in promoting malignant biological behavior of endometrial cancer cells by regulating TGF-β pathway and being modulated by TRPM2-AS/miR-424-5p axis for the first time. Taken together, this study suggested that PDIA6 may be a new candidate target for endometrial cancer therapy.
•The warming magnitudes of air temperature were summarized in the QTP and Mongolian on seasonal and annual scales.•The spatio-temporal changes of air freezing and thawing indices were characterized ...in the QTP and Mongolia.•The changes of air freezing and thawing indices could imply that the difference of warming characteristics in the QTP and Mongolia.•The changes of air freezing and thawing indices indicate that climate warming have great influence on the permafrost.
The majority of the Qinghai-Tibet Plateau (QTP) and Mongolia are underlain by permafrost. We have examined trends in air temperature and associated freezing/thawing index by using a non-parametric statistical method for the QTP and Mongolia from 1961 to 2011. The annual air temperature and associated freezing/thawing index exhibit similar patterns, suggesting similar warming trend in the two regions. The annual warming trends of air temperature are 0.33 °C/decade and 0.37 °C/decade in the QTP and Mongolia, respectively. The freezing index show significantly decreasing trends with −56.7 °C·days/decade and −57.5 °C·days/decade, while the thawing index present obvious increasing trends of 68.2 °C·days/decade and 68.3 °C·days/decade in the QTP and Mongolia, respectively. We find that the variations of air temperature and freezing/thawing index exhibit prominent spatial heterogeneity, and the warming trends is attributed to different seasonal warming. The warming trends in the QTP are dominated by winter warming, it is coincide with previous studies. Contrary to the QTP, autumn warming mainly accounts for the warming trends in the Mongolia. In addition, a winter cooling trend is observed in the Mongolia during the last two decades. These findings will be helpful to better understand the spatial heterogeneity of permafrost changes.
This study focuses on the large passenger flow control problem, after an operation interruption occurs, to develop a methodology that can efficiently control the passenger inflows of multiple ...stations and avoid overcrowding inside stations. An early-warning model for irregular large-scale passenger flows (ILSPF) and a dynamic ILSPF control model are proposed. The early-warning model is developed to predict passenger flows in the future with historical data and detect when to start control measures in actual time. The ILSPF cooperative control model focuses on cooperatively controlling the passenger inflows of multiple stations to ensure passenger safety in vehicles and stations, as well as maximize the number of passengers transported and minimize the passengers’ total waiting times. An improved particle swarm optimization algorithm was designed to determine an optimal solution, and a case study on the Chengdu metro in China was carried out to examine the performance of the model. The obtained results verify the effectiveness of the model and algorithm and prove that ILSPF control can regulate the passenger inflow demand, better match the passenger demand and capability on the line, increase the total number of passengers transported, and balance the proportion of passenger boarding at each station.
Railway systems may be interrupted by unforeseen events that require quick replanning to a feasible new schedule. This paper deals with the train rescheduling problem on double-track lines. The ...rescheduling problem is regarded as a conflict detection and resolution procedure. Timed Colored Petri nets are adopted to model the railway system: places represent rail resources, and tokens represent trains. A conflict detection rule is established in accordance with the safety principles of railway operations to predict potential conflicts. A Petri-net-based conflict resolution algorithm adapted from the A* algorithm is designed to search for an optimal or a near-optimal feasible schedule. The algorithm takes into account the railway operational principles when generating new markings, so that the new schedule has less train delays and respects the safety principles. The approach is applied in a case study to a double-track corridor from the Dutch railway network. For small delays, the algorithm can make delayed trains recover to their scheduled timetable within seconds. For large perturbations, the solutions generated by the algorithm can effectively reduce train delays while ensuring traffic safety.
An energy-efficient train trajectory corresponds to the speed profile of a train between two stations that minimizes energy consumption while respecting the scheduled arrival time and operational ...constraints such as speed limits. Determining this trajectory is a well-known problem in the operations research and transport literature, but has so far been studied without accounting for stochastic variables like weather conditions or train load that in reality vary in each journey. These variables have an impact on the train resistance, which in turn affects the energy consumption. In this paper, we focus on wind variability and propose a train resistance equation that accounts for the impact of wind speed and direction explicitly on the train motion. Based on this equation, we compute the energy-efficient speed profile that exploits the knowledge of wind available before train departure, i.e., wind measurements and forecasts. Specifically, we: (i) construct a distance-speed network that relies on a new non-linear discretization of speed values and embeds the physical train motion relations updated with the wind data, and (ii) compute the energy-efficient trajectory by combining a line-search framework with a dynamic programming shortest path algorithm. Extensive numerical experiments reveal that our “wind-aware” train trajectories present different shape and reduce energy consumption compared to traditional speed profiles computed regardless of any wind information.
Epithelial ovarian cancer (EOC) is the main pathological type of ovarian cancer. In this study, we found that ependymin-related 1 (EPDR1) was remarkably downregulated in EOC tissues, and low EPDR1 ...expression was associated with International Federation of Gynecology and Obstetrics (FIGO) stage, metastasis, and poor prognosis. We confirmed that EPDR1 overexpression dramatically suppressed EOC cell proliferation, migration, and invasion
and
. Mechanistically, EPDR1 inhibited EOC tumorigenesis and progression, at least in part, through the repression of the PI3K (Phosphoinositide 3-kinase)/AKT (AKT Serine/Threonine Kinase 1) signaling pathway. Furthermore, the expression and function of EPDR1 were regulated by miR-429, as demonstrated by luciferase reporter assays and rescue experiments. In conclusion, our study validated that EPDR1, negatively regulated by miR-429, played an important role as a tumor-suppressor gene in EOC development
inhibition of the PI3K/AKT pathway. The miR-429/EPDR1 axis might provide novel therapeutic targets for individualized treatment of EOC patients in the future.
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