scholarly journals Walkability Assessment in a Rapidly Urbanizing City and Its Relationship with Residential Estate Value

2019 ◽  
Vol 11 (8) ◽  
pp. 2205 ◽  
Author(s):  
Jingyuan Zhang ◽  
Puay Yok Tan ◽  
Hui Zeng ◽  
Ye Zhang

Walkability has increasingly been recognized as an important factor for sustainable urban development that, however, has seldom been investigated in rapid urbanizing cities, especially in the Asian context. This paper assessed walkability in Futian District in the central area of Shenzhen, which has undergone very rapid urbanization within a short period of time. Walkability was assessed for 2013 and 2018 using a walkability index adapted from Walk Score. It was compared with housing prices of 215 randomly selected residential buildings, to further explore the relationships between walkability and residential estate value, provided as one practical application of the assessment of walkability in urban management. Our results show that Futian District has low walkability level, although walkability has been generally improved from 2013 to 2018. A high spatial variation of walkability level within this area was observed in both years. Overall, there was a negative relationship between walkability and housing prices (significant only in 2018), which is inconsistent with studies elsewhere. The results suggest that the housing prices in Futian District are more strongly influenced by other factors rather than by walkability. In addition, the ability of the walkability model to explicitly delineate spatial variation of walkability level makes it a powerful tool to be applied in urban planning and management. Results of this study also have practical applications, which can be used as a reference for residents’ home selection and enable them to make informed decisions in selecting walkable neighborhoods with acceptable prices.

2019 ◽  
Vol 26 (10) ◽  
pp. 776-784
Author(s):  
Rui Yang ◽  
Yu Tao ◽  
Gaojian Li ◽  
Jian Chen ◽  
Jianhong Shu ◽  
...  

Background:Porcine circovirus and Mycoplasma hyopneumoniae can cause respiratory diseases in pigs, which cause serious economic loss in the worldwide pig industry. Currently, these infections are mainly prevented and controlled by vaccination. The new vaccines on the market are mainly composed of subunits and inactivated vaccines but usually have lower antigenicity than traditional live vaccines. Thus, there is an increasing need to develop new adjuvants that can cause rapid and long-lasting immunity to enhance the antigenic efficacy for vaccines. Studies have shown that meningococcal porin PorB can act as a ligand to combine with Toll-like receptors to activate the production of immunological projections and act as a vaccine immunological adjuvant.Objective:In this article, we expressed and purified the recombinant PorB protein and verified its immunogenicity against porcine circovirus type 2 and Mycoplasma hyopneumoniae genetically engineered vaccine.Methods:In this article, we used prokaryotic expression to express and purify recombinant PorB protein, four different concentrations of PorB protein, Freund's adjuvant with two genetically engineered vaccines were combined with subcutaneous immunization of mice.Results:Our study shows that the appropriate dose of the recombinant protein PorB can enhance the levels of humoral and cellular responses induced by two genetically engineered vaccines in a short period of time in mice. The PorB adjuvant group may cause statistically higher antibody titers for both genetically engineered vaccines compared to Freund's commercial adjuvant (P<0.001).Conclusion:The recombinant protein PorB may be a good candidate adjuvant for improving the protective effect of vaccines against porcine circovirus type 2 and Mycoplasma hyopneumoniae, and the protein can be used for future practical applications.


Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 359
Author(s):  
Zhouqiao Ren ◽  
Jianhua He ◽  
Qiaobing Yue

Landscape connectivity is important for all organisms as it directly affects population dynamics. Yet, rapid urbanization has caused serious landscape fragmentation, which is the primary contributor of species extinctions worldwide. Previous studies have mostly used spatial snap-shots to evaluate the impact of urban expansion on landscape connectivity. However, the interactions among habitats over time in dynamic landscapes have been largely ignored. Here, we demonstrated that overlooking temporal connectivity can lead to the overestimation of the impact of urban expansion. How much greater the overestimation is depends on the amount of net habitat loss. Moreover, we showed that landscape connectivity may have a delayed response to urban expansion. Our analysis shifts the way to understand the ecological consequences of urban expansion. Our framework can guide sustainable urban development and can be inspiring to conservation practices under other contexts (e.g., climate change).


Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1374
Author(s):  
Hefei Wang ◽  
Zongping Pei

The undergoing trend and development towards urbanization and the consequences of socio-ecological and climate change are increasing the pressure on cities worldwide. The planning of urban green and blue spaces is essential for sustainable urban development, especially for the conservation of urban ecosystems in fast-growing cities. In this context, the spatial-explicit and ecological connectivity analyses of urban green infrastructure are helpful tools for planning and the evaluation of spatial patterns and their changes for the sustainability of urban development. The aim of this study is to understand the influence of urban expansion on the urban green corridors. In this paper, we present an analysis of ecological networks for green infrastructure planning at the city level, making the most out of morphological spatial pattern analysis (MSPA) techniques and social-ecological analysis methods. The findings reveal the changes of spatial patterns of urban green and blue areas in Gaoyou city and disclose its ecological corridors and connectivity from 1990 to 2012. The urban green corridors analysis method proposed here can be used in other cities and allow for the production of spatially detailed urban ecological connectivity assessment and monitoring. Recommendations to enhance and conserve green corridors and ecological networks such as reserving networks in the east of the example city have been concluded. The conclusion obtained using our spatial analysis method can be used in other municipalities to serve as spatial-explicit tools for urban green spaces and land use planning.


2021 ◽  
Vol 14 (11) ◽  
pp. 1140
Author(s):  
Miki Sato-Akushichi ◽  
Shinji Ono ◽  
Gerd Klose ◽  
Youngseok Song

To evaluate choroidal volume and thickness changes after photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC). Chronic CSC eyes with a history of PDT were selected. Average choroidal volume, average choroidal thickness, the maximum and minimum choroidal thickness of the macula irradiated area and peripheral non-irradiated areas before and after one and three months of treatment were examined. A total of 14 patients with chronic CSC and 9 controls without any eye pathology were enrolled. The mean choroidal volume in CSC before and, and after one and three months of treatment were 2.36 (standard deviation: 0.70), 1.90 (0.69), 1.86 (0.66) mm3 for the central area, 1.25 (0.38), 1.14 (0.35), 1.13 (0.34) mm3 for superior nasal area, 1.47 (0.41), 1.28 (0.43), 1.26 (0.43) mm3 for superior temporal area, 1.07 (0.49), 0.95 (0.38), 0.93 (0.35) mm3 for inferior nasal area, 1.17 (0.38), 1.04 (0.32), 1.03 (0.33) mm3 for inferior temporal area. This study revealed the choroidal volume changes in a short period after PDT and a decrease in unirradiated choroidal volume was also shown after the treatment. The algorithm provided on the ARI Network enables to evaluate the choroidal changes quantitatively and qualitatively.


Author(s):  
Sanjana Ahmad ◽  
David L. Greene

Since 1975, the fuel economy of passenger cars and light trucks has been regulated by the corporate average fuel economy (CAFE) standards, established during the energy crises of the 1970s. Calls to increase fuel economy are usually met by a fierce debate on the effectiveness of the CAFE standards and their impact on highway safety. A seminal study of the link between CAFE and traffic fatalities was published by R. W. Crandall and J. D. Graham in 1989. They linked higher fuel economy levels to decreases in vehicle weight and correlated the decline in new car weight with about a 20% increase in occupant fatalities. The time series available to them, 1947–1981, includes only the first 4 years of fuel economy regulation, but any statistical relationship estimated over such a short period is questionable. This paper reexamines the relationship between U.S. light-duty vehicle fuel economy and highway fatalities from 1966 to 2002. Cointegration analysis reveals that the stationary linear relationships between the average fuel economy of passenger cars and light trucks and highway fatalities are negative: higher miles per gallon is significantly correlated with fewer fatalities. Log–log models are not stable and tend to produce statistically insignificant (negative) relationships between fuel economy and traffic fatalities. These results do not definitively establish a negative relationship between light-duty vehicle fuel economy and highway fatalities; instead they demonstrate that national aggregate statistics cannot support the assertion that increased fuel economy has led to increased traffic fatalities.


2019 ◽  
Vol 11 (21) ◽  
pp. 5919 ◽  
Author(s):  
He ◽  
Mai ◽  
Shen

For megacities experiencing rapid urbanization in China, urban growth boundaries (UGBs) have been considered as a useful means to control urban sprawl and to promote sustainable urban development. However, scientific methods and tools to delineate sound UGBs by planners are few and far between. Using metropolitan Chengdu as the study area, this paper applies the system dynamics (SD) and conversion of land use and its effects at small region extent (CLUE-s) models to delineate UGBs. In this study, land use demand was simulated in the SD model temporally at a macro-level and allocated in the CLUE-s model spatially at a micro-level. Key social-economic elements and spatial pattern factors were used in the simulation process for the period of 2013–2030. The simulation results under various scenarios showed that areas along the major corridors and belt roads of the main Chengdu metropolitan area and its satellite towns have higher chances to be developed. The areas most likely to be developed were used to establish the UGBs for 2020, 2025, and 2030. This research demonstrates that the integrated framework of SD and CLUE-s models provides a feasible means of UGB delineation under different development scenarios.


2020 ◽  
Vol 1603 ◽  
pp. 012027
Author(s):  
P Morano ◽  
C Guarnaccia ◽  
F Tajani ◽  
F Di Liddo ◽  
D Anelli

2019 ◽  
Vol 11 (7) ◽  
pp. 2073
Author(s):  
Cheng Li ◽  
Ranghui Wang ◽  
Fangmin Zhang ◽  
Yunjian Luo ◽  
Yong Huang

Ecosystem services are comprehensive and quantitative indicators for describing ecosystem–human interactions. China has experienced rapid urbanization in the past 30 years, which has created a significant impact on regional ecosystem services. However, whether the impact is linear is not clear as yet. In this study, the Jiangsu province, a main body of the Chinese Yangtze River Delta city cluster, was chosen as a case study. Multi-source remotely-sensed geospatial data, including meteorological, land use, vegetation, and socio-economic data, were collected to estimate the total amount of ecosystem services (TESV) and urbanization levels. Subsequently, the relationships between TESV and urbanization indices (i.e., gross domestic product (GDP) per unit area, GPUA; population per unit area, PPUA; and built-up land proportion, BULP) were determined using the Pearson correlation analysis and piecewise linear regression. The primary findings of this study were as follows: (1) There was a distinct spatial pattern in TESV, which gradually increased from west to east with high-value areas located in eastern coastal areas of Jiangsu. Among different land use types, cropland and woodland contributed the most to TESV; (2) The three urbanization indices had spatial patterns, indicating higher urbanization in southern Jiangsu than in central or northern Jiangsu; and (3) Once GPUA and PPUA exceeded threshold values of 3719.55 × 104 yuan/km2 and 744.37 person/km2, respectively, TESV sharply decreased with an increase in these indices. However, the BULP showed a linear and significantly negative relationship with TESV at all values, which indicated that the impacts of economic and population growth on TESV lagged behind that of built-up land expansion. These findings provide a potentially significant reference for decision-makers to rationally enhance regional ecosystem services during rapid urbanization processes.


2020 ◽  
Vol 12 (7) ◽  
pp. 2643 ◽  
Author(s):  
Xiaoqing Lin ◽  
Chunyan Lu ◽  
Kaishan Song ◽  
Ying Su ◽  
Yifan Lei ◽  
...  

Rapid urbanization has affected the eco-environment in China. A clear understanding of the coupling relationship between urbanization quality and eco-environment pressure is needed for sustainable urban development. This study focused on the relationship between urbanization quality and eco-environment pressure in the West Taiwan Strait Urban Agglomeration (WTSUA) with panel data collected from 2003 to 2017. An index system was established to measure urbanization quality from four urbanization subsystems: demographic urbanization, spatial urbanization, economic urbanization, and social urbanization. An index of eco-environment pressure was developed from resource availability, energy consumption, pollution emissions, and pressure response. The level of urbanization quality and eco-environment pressure was assessed using analytic hierarchy process (AHP) and entropy method (EM). The coupling process was described using a coupling coordination degree model. Results showed the following: (1) Economic urbanization contributed the most to urbanization quality. The contribution of the four subsystems to eco-environment pressure was similar. (2) Eco-environment pressure decreased with improving urbanization quality. The coupling coordination degree between urbanization quality and eco-environment pressure increased. Spatially, the coupling coordination degree of eastern cities was higher than that of western cities. The findings of this paper will help government in planning and implementing sustainable urban development and eco-environment conservation.


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