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This article studies the impacts of disaster- and evacuation-related information from various information sources on university campus community members’ evacuation decision-making process during n...

WFOS (Wide-Field Optical Spectrograph) is a first light instrument mounted on the Nasmyth focus of the TMT (Thirty Meter Telescope). The transient analysis was performed under infrequent earthquakes to study the WFOS shell structure's transient response using Abaqus software. Computer-aided design models of WFOS shell structure were established using Invar (4J32), a nickel-iron alloy, as the selected structural material. Time history analysis was performed on the WFOS structure under seven different earthquake time histories, and the structural responses of displacement, stress, and acceleration were investigated. the peak acceleration is reached when the support structure is dealt against seven infrequent earthquakes in three directions. This research's methodology and outcomes provide a guidance approach to seismic response analysis of the telescope components. A detailed briefing of the computer-aided design model and results are presented.

Aiming at the issues of heavy weight and insufficient structural performance of optical instrument supporting structures in extremely large telescopes, the Wide-Field Optical Spectrograph (WFOS) of the Thirty Meter Telescope (TMT) was taken as a case to study. In order to develop lightweight structures which satisfies the design requirements for mass and stiffness, a design scheme of cylindrical composite shells supporting structure was proposed and their finite element models were developed. A size optimisation and a ply sequence optimisation of the composite structure were carried out. The structures before and after optimisation were evaluated from the aspects of mass, displacement, failure index and fundamental frequency. After the optimised design, the mass of the optimised WFOS cylindrical composite shell structure is reduced to approximately 50%, but its maximum displacement (0.513 mm) and fundamental frequency (8.275 Hz) are nearly unchanged. The study indicates that a cylindrical composite shell structure is an efficient structural form for large optical instruments.

Unintentional injuries pose a great risk for human health in China. Few studies have focused on unintentional injuries at national level from urbanization perspective. The panel data of mortality rate of transportation accidents (TA), fall and drowning and sinking (DS) is investigated, and urbanization development index is collected. Global Moran's I and linear regression of panel data are applied to determine the spatial distribution and spatial influencing factors of unintentional injuries. The results are the following: (1) The unintentional injury such as TA, fall, and DS shows clear non-uniformity of spatial distribution and relative immobility through time. (2) A 10,000 tons increase in SO2 emission amount (SO2 EA) and emission of smoke and dust (ESD) can result in 15.7 and 12.5 increases in TA death in eastern region, respectively. Meanwhile, A 10,000 tons increase in NOx emission amount can cause 15.1 increase in TA death in western region. For every 100 billion yuan increase in GDP, the fall death can reduce by 8.4 in central region. One bed increase in number of hospital beds per 10,000 population (NHBP) is favorable for decreasing in fall death by 16.7 in eastern region. However, increase in number of workers enjoying industrial injury (NEWII) does not reduce the fall death in eastern region. (3) For every 1 ten thousand people increase in number of students in ordinary high schools (NSOHS) is conductive to reducing DS death by 7.8 in the western region. Our findings show that there exist spatial differences for urbanization influencing TA, fall, and DS death in eastern, western, and central regions. This study is expected to provide a reference for unintentional injuries control in those three regions.

Calcium ions can react with polyethylene glycol (PEG) to form a form-stable phase change material, but the low thermal conductivity hinders its practical application. In this paper, hydroxylated multi-walled carbon nanotubes (MWCNTs) with different mass are introduced into PEG1500·CaCl2 form-stable phase change material to prepare a new type of energy storage material. Carbon nanotubes increased the mean free path (MFP) of phonons and effectively reduced the interfacial thermal resistance between pure PEG and PEG1500·CaCl2 3D skeleton structure. Thermal conductivity was significant improved after increasing MWCNTs mass, while the latent heat decreases. At 1.5 wt%, composite material shows the highest phase change temperature of 42 °C, and its thermal conductivity is 291.30% higher than pure PEG1500·CaCl2. This article can provide some suggestions for the preparation and application of high thermal conductivity form-stable phase change materials.

With the progress of information and sensing technologies, estimating vehicular queue length at signalized intersections becomes feasible and has attracted considerable attention. The existing studies provided a solid theoretical foundation for the estimation; however, the studies have some restrictions or limitations more or less. This paper presents a new methodology for estimating vehicular queue length at signalized intersections using multi-source detection data under both undersaturated and oversaturated conditions. The methodology applies the shockwave theory to model queue dynamics. Using data from probe vehicles and point detectors, analytical formulations for calculating the maximum and minimum (residual) queue lengths of each cycle are developed. Ground truth data were collected from numerical experiments conducted at two intersections in Shanghai, China, to verify the proposed methodology. It is found that the methodology has mean absolute percentage errors of 17.09% and 12.28%, respec...

Antimony (Sb) pollution has become a pressing environmental problem in recent years. Trees have been proven to have great potential for the feasible phytomanagement; however, little is known about Sb retention and tolerance in trees. The Chinese cork oak (Quercus variabilis Bl.) is known to be capable of growth in soils containing high concentrations of Sb. This study explored in detail the retention and acclimation of Q. variabilis under moderate and high external Sb levels. Results revealed that Q. variabilis could tolerate and accumulate high Sb (1623.39 mg kg−1 DW) in roots. Dynamics of Sb retention in leaves, stems, and roots of Q. variabilis were different. Leaf Sb remained at a certain level for several weeks, while in roots and stems, Sb concentrations continued to increase. Sb damaged tree’s PSII reaction cores but elicited defense mechanism at the donor side of PSII. It affected the electron transport flow after QA − more strongly than the oxygen-evolving complex and light-harvesting pigment-protein complex II. Sb also decreased leaf chlorophyll concentrations and therefore inhibited plant growth. During acclimation to Sb toxicity, Sb concentrations in leaves, stems, and roots decreased, with photosynthetic activity and pigments recovering to normal levels by the end of the experiment. These findings suggest that Sb tolerance in Q. variabilis is inducible. Acclimation seems to be related to homeostasis of Sb in plants. Results of this study can provide useful information for trees breeding and selection of Sb phytomanagement strategies, exploiting the established ability of Q. variabilis to transport, delocalize in the leaves, and tolerate Sb pollutions.

With the growth in traffic sensing data, the measurement of levels of service such as queue length at intersections in real time has been receiving considerable attention. This paper examines how to estimate real-time cycle-by-cycle queue length at signalized intersections by using the data of an upstream point sensor and the traveling trajectory of a probe vehicle observed by a mobile sensor. Three cases are based on the space relationships between the rear of a queue, the point sensor location, and the vehicle stop or start-up point. When the data of point sensors and mobile sensors are fused, critical break points can be identified to indicate several key states of the queue formation and dissipation. Estimation models of the maximum queue length, based on the Lighthill-Whitham-Richards theory, are proposed for the three cases. The presented algorithm does not impose any restrictions on the traffic condition (i.e., oversaturated and undersaturated conditions). The methodology is applied to ground truth...

Background Glutamate decarboxylase (GAD), as a key enzyme in the γ -aminobutyric acid (GABA) shunt, catalyzes the decarboxylation of L-glutamate to form GABA. This pathway has attracted much interest because of its roles in carbon and nitrogen metabolism, stress responses, and signaling in higher plants. The aim of this study was to isolate and characterize genes encoding GADs from Caragana intermedia, an important nitrogen-fixing leguminous shrub. Methods Two full-length cDNAs encoding GADs (designated as CiGAD1 and CiGAD2) were isolated and characterized. Multiple alignment and phylogenetic analyses were conducted to evaluate their structures and identities to each other and to homologs in other plants. Tissue expression analyses were conducted to evaluate their transcriptional responses to stress (NaCl, ZnSO4, CdCl2, high/low temperature, and dehydration) and exogenous abscisic acid. Results The CiGADs contained the conserved PLP domain and calmodulin (CaM)-binding domain in the C-terminal region. The phylogenetic analysis showed that they were more closely related to the GADs of soybean, another legume, than to GADs of other model plants. According to Southern blotting analysis, CiGAD1 had one copy and CiGAD2-related genes were present as two copies in C. intermedia. In the tissue expression analyses, there were much higher transcript levels of CiGAD2 than CiGAD1 in bark, suggesting that CiGAD2 might play a role in secondary growth of woody plants. Several stress treatments (NaCl, ZnSO4, CdCl2, high/low temperature, and dehydration) significantly increased the transcript levels of both CiGADs, except for CiGAD2 under Cd stress. The CiGAD1 transcript levels strongly increased in response to Zn stress (74.3-fold increase in roots) and heat stress (218.1-fold increase in leaves). The transcript levels of both CiGADs significantly increased as GABA accumulated during a 24-h salt treatment. Abscisic acid was involved in regulating the expression of these two CiGADs under salt stress. Discussion This study showed that two CiGADs cloned from C. intermedia are closely related to homologs in another legume, soybean. CiGAD2 expression was much higher than that of CiGAD1 in bark, indicating that CiGAD2 might participate in the process of secondary growth in woody plants. Multiple stresses, interestingly, showed that Zn and heat stresses had the strongest effects on CiGAD1 expression, suggesting that CiGAD1 plays important roles in the responses to Zn and heat stresses. Additionally, these two genes might be involved in ABA dependent pathway during stress. This result provides important information about the role of GADs in woody plants’ responses to environmental stresses.

We propose a new estimation method for the factor loading matrix in modelling multivariate volatility processes. The key step of the method is based on the weighted scatter estimators, which does not involve optimizing any objective function. The method can therefore be easily applied to high-dimensional systems without running into computational problems. The estimation is proved to be consistent and the asymptotic distribution is derived. The method inherits robust properties in dealing with ‘outlier’ clusters generated by GARCH processes. Through both simulation and real-world case studies, we show that the method works well.

In order to integrate weather data into traffic operations, this paper proposed a multi-state prediction model under rainfall according to the concept of three-phase traffic flow theory. Based on the data collected from the North-South expressway in Shanghai, traffic states were first divided into three classes through wavelet analysis. Then the multi-state prediction model was proposed using linear regression analysis of traffic characteristics under rainfall. The relationship between speed variation rate and precipitation was analyzed separately under different traffic states. Finally, speed adjustment factors under different traffic states and rainy conditions were given in a practice case.

Background Glutamate decarboxylase (GAD), as a key enzyme in the γ -aminobutyric acid (GABA) shunt, catalyzes the decarboxylation of L-glutamate to form GABA. This pathway has attracted much interest because of its roles in carbon and nitrogen metabolism, stress responses, and signaling in higher plants. The aim of this study was to isolate and characterize genes encoding GADs from Caragana intermedia, an important nitrogen-fixing leguminous shrub. Methods Two full-length cDNAs encoding GADs (designated as CiGAD1 and CiGAD2) were isolated and characterized. Multiple alignment and phylogenetic analyses were conducted to evaluate their structures and identities to each other and to homologs in other plants. Tissue expression analyses were conducted to evaluate their transcriptional responses to stress (NaCl, ZnSO4, CdCl2, high/low temperature, and dehydration) and exogenous abscisic acid. Results The CiGADs contained the conserved PLP domain and calmodulin (CaM)-binding domain in the C-terminal region. The phylogenetic analysis showed that they were more closely related to the GADs of soybean, another legume, than to GADs of other model plants. According to Southern blotting analysis, CiGAD1 had one copy and CiGAD2-related genes were present as two copies in C. intermedia. In the tissue expression analyses, there were much higher transcript levels of CiGAD2 than CiGAD1 in bark, suggesting that CiGAD2 might play a role in secondary growth of woody plants. Several stress treatments (NaCl, ZnSO4, CdCl2, high/low temperature, and dehydration) significantly increased the transcript levels of both CiGADs, except for CiGAD2 under Cd stress. The CiGAD1 transcript levels strongly increased in response to Zn stress (74.3-fold increase in roots) and heat stress (218.1-fold increase in leaves). The transcript levels of both CiGADs significantly increased as GABA accumulated during a 24-h salt treatment. Abscisic acid was involved in regulating the expression of these two CiGADs under salt stress. Discussion This study showed that two CiGADs cloned from C. intermedia are closely related to homologs in another legume, soybean. CiGAD2 expression was much higher than that of CiGAD1 in bark, indicating that CiGAD2 might participate in the process of secondary growth in woody plants. Multiple stresses, interestingly, showed that Zn and heat stresses had the strongest effects on CiGAD1 expression, suggesting that CiGAD1 plays important roles in the responses to Zn and heat stresses. Additionally, these two genes might be involved in ABA dependent pathway during stress. This result provides important information about the role of GADs in woody plants’ responses to environmental stresses.

Due to the limitations of several different kinds of detectors currently in use, typical ways to estimate travel time on urban streets -- based on the data collected by only one source -- are no longer suitable. Moreover, traditional methods of estimating travel time based on all vehicle types on urban streets are unable to provide specific travel times to travelers. This paper aims at providing a model based on data fusion of multisource data to estimate travel times of different vehicle types on urban streets. A weighting calculation that fuses data collected by loop detectors and floating cars is used to build a travel time estimation model for urban road links. The aforementioned fusion method is verified by the simulation software VISSIM. The simulation results lead to the conclusion that this travel time estimation model performs better than the estimation model based on only loop detector or floating car data. The relative error (RE) of travel time is within the range of 10% to 20%. Limitations of the proposed method are also discussed in this paper.