Longer afterschool active commutes and the travel environment of middle schools in Shenzhen, China

The afterschool commute is a major part of children's daily activity. This study examines the relationship between student extended active travel routes and route environment characteristics. Route environment characteristics may be related to an extended route for students who walk or bike home. Self-reported itineraries were collected from 12 to 15-year old students in 3 middle schools in Shenzhen in May and June (n = 1257). Itineraries involving a detour from the shortest possible route home (n = 437) were compared with the shortest route. A field study coded all possible routes within the school districts by playable open spaces, sidewalk width, controlled crossings, road category, and public transit stops. Binary logistic regression reveals that routes with greater intersection density and number of open spaces are related to active travel choice. Sidewalk width, number of traffic lights and proportion of arterial roads are positively related to motorized travel. Linear regression reveals that travel distance, sidewalk width, number of open spaces and street crossings, as well as the proportion of secondary roads and pathways are positively related to detour distance. Higher numbers of public transit stops and traffic lights are related to shorter detours. Attending cram school is also negatively associated with active travel and detour. Younger students, females and students with longer moderate-to-vigorous physical activity time have extended active travel. Specific route environment characteristics are associated with longer and more active middle school student commutes and may be implemented to raise overall activity levels in children. Keywords: Afterschool commute, Route environment, Active travel, Route choice, Middle schoo

Local environment and social factors in primary school children's afterschool commute in China

The rapid decline in young children's active commutes to and from school has prompted investigations into ways to raise activity levels. The period after school is recognized as very important in the daily activity regime of primary school children. In this study, we examine the relative effects of local environmental factors and socio-economic status on children's after-school commute mode choice. Environmental factors are pedestrian priority streets, street intersection density, motorways, shops, and play spaces. Property values are used as a proxy for income. Twenty-four school districts are selected using intersection density and motorway length as criteria. All children's exit behaviors were film-recorded on October weekdays and extracted as four choices–alone, in a group of children, on foot with a parent or guardian, on e-bike driven by an adult. A multinomial logistic regression reveals that gated communities, higher priced housing, motorways and bus stops are associated with children accompanied by adults. The presence of pedestrian streets is associated with children travelling alone and in groups. Greater travel distance is also associated with parents accompanying children on foot or on e-bike. The amount of play space is associated with children leaving school in groups. Overall, social and environmental factors are influential in the independent travel of primary school children after the school day ends in south China

Low Impact Thinking of the Spongy City Construction in Built-Up Areas from the Perspective of Sustainable Urban Design

Sponge city construction can improve cities’ ability to adapt to the environment change and the ability to cope with floods, and it can also prompt cities’ development to be more healthy and sustainable. However, the process itself of sponge city construction may also has impact on the environment especially in built-up areas, to reduce the impact, the rainwater landscape design needs to integrate sustainable thoughts as follows: (1) balancing earthwork on site. Borrowing the traditional Chinese concept of "dig lake and pile mountain", providing earthwork balance on site by adjusting the micro-topography. (2) Protecting trees and bushes on site. When introducing bio-retention ponds to the built-up area with new plants which will be drought-resistant and wet-resistant, perennial, and with low maintenance, the designers need to think about how to protect and rearrange the existing plants especially trees and bushes at the same time which are relatively stable and mature in green spaces of old town. (3) Recycling the existing paving materials. Impermeable paving material on sidewalk, square, pedestrian area, parking area, etc. will be replaced by permeable concrete, permeable bricks, gravel, other permeable materials, and waterway kerbs. These abandoned materials could be recycled on site, such as use of the old concrete slabs, bricks building short stone walls to divide space or seats for people to rest, and it will reduce a lot of construction waste and avoid the pollution of new material consummations to the environment. (4) Taking the opportunity of spongy city construction to improve urban non-motor vehicle traffic environment, raising bike lanes along roads outside blocks and small roads inside blocks with permeable asphalt to improve walking and biking environment in cities. (5) Making public open spaces such as squares and green spaces support more staying activities with the opportunity of introducing rain garden to these areas. This is a kind of sustainable urban design point of view. Following the principle of minimum energy and material consumption and reducing the impact of sponge city construction itself on the environment will avoid a new round of environmental problems and resource waste. It has important significance to the construction of ecological city

Public Attitudes about Urban Lawns : Social Opportunities Provided by Urban Lawns in Lund, Sweden

Since the 19th century, urban lawns have gradually taken center stage to become one of the main sources of greening in many cities around the world. The current published research on planting technology, maintenance techniques, the impact of lawn maintenance, preferences for manicured lawns and the biodiversity protection for historical lawns as topics, has developed and increased over time. However, what has been less researched is the relationship and interplay between the perceptions of urban residents and their use of urban lawns. More specifically, our research focused on the question of how residents view, socialize and utilize city lawns accessible to them. To provide some insight into this area of urban lawn use, our research study was conducted in Lund, Sweden a city that uses lawns as their main form of greening. To accomplish the study’s objectives the city's lawns were grouped into the following categories:(1) park lawns, (2) residential neighborhood lawns, (3) lawns around public buildings, (4) lawns surrounding residential buildings, (5) lawns along greenways and (6) lawns along roads. By means of distributed open-ended questionnaires the researchers discovered two important findings. First, the socialization patterns and utilization of lawns differed between the six categories due to various factors which included the suitability of the land use. The data also showed that the efficiency of planting lawns in certain areas impacts the ability to access areas for socialization activities (i.e. roadsides and greenways). Secondly, the study revealed that the planting collocation and service facilities of lawns greatly influences residents' ability and opportunities for social interaction. Two other study findings were of interest namely that (1) the utilization of lawns among Lund’s working class was somewhat lower than that of students; and (2) that socialization and use of lawns were not necessarily related to the user's accustomed environmental background. Subsequently, this article discusses key themes that include residents’ attitudes, beliefs and opinions about the interaction of socializing and the meaning of those interactions in an urban environment. It is our purpose that this article spurs a more robust international dialogue about pragmatic lessons urban planners may learn about future designing efforts of urban green space in newly developing cities and established ones already confronting modern space and housing challenges

Effects of Boron Content on the Microstructure and Impact Toughness of 12Cr1MoVR Low-Alloy Heat-Resistant Steel Weld Metals

The impact toughness of low-Cr heat-resistant steel weld metal is an important problem to broaden the application of low-Cr heat-resistant steel. In this study, the microstructure and impact toughness of 12Cr1MoVR low-alloy heat-resistant steel weld metals with various boron contents (B1 = 0.0028%, B2 = 0.0054%, and B3 = 0.0079%) were investigated. The microstructures of all weld metals were composed of block ferrite, carbides, and inclusions. Results indicated that with increased B content, prior austenite grain sizes decreased, and minor microstructure changes could be found. With the increase in B content from 0.0028% to 0.0054% to 0.0079%, the ductile–brittle transition temperature of the weld metals decreased from 30 to 0 to −14 °C, the toughness of weld metal increased, and the hardness slightly decreased, all of which are directly related to the refinement of prior austenite grain size because of the addition of B content. However, on the top-shelf zone, such as at the testing temperature of 80 °C, ductile fracture dominates the fracture surface; with the increase in B content, the size and density of inclusions increased gradually, which led to the decrease of the impact toughness at 80 °C when the B content was 0.0079%

Neuroprotective Effects of the Sonic Hedgehog Signaling Pathway in Ischemic Injury through Promotion of Synaptic and Neuronal Health

Cerebral ischemia is a common cerebrovascular condition which often induces neuronal apoptosis, leading to brain damage. The sonic hedgehog (Shh) signaling pathway has been reported to be involved in ischemic stroke, but the underlying mechanisms have not been fully elucidated. In the present study, we demonstrated that expressions of Shh, Ptch, and Gli-1 were significantly downregulated at 24 h following oxygen-glucose deprivation (OGD) injury in neurons in vitro, effects which were associated with increasing numbers of apoptotic cells and reactive oxygen species generation. In addition, expressions of synaptic proteins (neuroligin and neurexin) were significantly downregulated at 8 h following OGD, also associated with concomitant neuronal apoptosis. Treatment with purmorphamine, a Shh agonist, increased Gli-1 in the nucleus of neurons and protected against OGD injury, whereas the Shh inhibitor, cyclopamine, produced the opposite effects. Activation of Shh signals promoted CREB and Akt phosphorylation; upregulated the expressions of BDNF, neuroligin, and neurexin; and decreased NF-κB phosphorylation following OGD. Notably, this activation of Shh signals was accompanied by improved neurobehavioral responses along with attenuations in edema and apoptosis at 48 h postischemic insult in rats. Taken together, these results demonstrate that activation of the Shh signaling pathway played a neuroprotective role in response to ischemic exposure via promotion of synaptic and neuronal health

Hydrogen Evolution Reaction on Hybrid Catalysts of Vertical MoS₂ Nanosheets and Hydrogenated Graphene

Two-dimensional (2D) molybdenum sulfide (MoS₂) is an attractive noble-metal-free electrocatalyst for hydrogen evolution (HER) in acids. Tremendous effort has been made to engineer MoS₂ catalysts with either more active sites or higher conductivity to enhance their HER activity. However, little attention has been paid to synergistically structural and electronic modulations of MoS₂. Herein, 2D hydrogenated graphene (HG) is introduced into MoS₂ ultrathin nanosheets for the construction of a highly efficient and stable catalyst for HER. Owing to synergistic modulations of both structural and electronic benefits to MoS₂ nanosheets via HG support, such a catalyst has improved conductivity, more accessible catalytic active sites, and moderate hydrogen adsorption energy. On the optimized MoS₂/HG hybrid catalyst, HER occurs with an overpotential of 124 mV at 10 mA cm^–2, a Tafel slope of 41 mV dec^–1, and a stable durability for 24 h continuous operation at 30 mA cm^–2 without observable fading. The high performance of the optimized MoS₂/HG hybrid catalyst for HER was interpreted with density functional theory calculations. The simulation results reveal that the introduction of HG modulates the electronic structure of MoS₂ to increase the number of active sites and simultaneously optimizes the hydrogen adsorption energy at S-edge atoms, eventually promoting HER activity. This study thus provides a strategy to design and develop high-performance HER electrocatalysts by employing different 2D materials

Porous framework materials for energy & environment relevant applications:A systematic review

Carbon peaking and carbon neutralization trigger a technical revolution in energy & environment related fields. Development of new technologies for green energy production and storage, industrial energy saving and efficiency reinforcement, carbon capture, and pollutant gas treatment is in highly imperious demand. The emerging porous framework materials such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), owing to the permanent porosity, tremendous specific surface area, designable structure and customizable functionality, have shown great potential in major energy-consuming industrial processes, including sustainable energy gas catalytic conversion, energy-efficient industrial gas separation and storage. Herein, this manuscript presents a systematic review of porous framework materials for global and comprehensive energy & environment related applications, from a macroscopic and application perspective