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Increasing urbanization in China has caused severe haze pollution in Chinese cities in recent years. This study investigates the impact of urban spatial development mode on haze pollution from the leapfrog spatial dimension. We constructed a dataset containing LandScan population dynamic statistical data, PM2.5 surface concentration data, and urban economic statistical data and adopted ordinary least squares (OLS) and instrumental variable methods. The findings indicate that the polycentric spatial structure within the city increases the PM2.5 levels, indicating that the urban monocentric spatial development mode is conducive to alleviating haze pollution. The use of the core explanatory variables, lagged by one and two periods, and of the number of Qing Dynasty walls as the instrumental variable confirm the robustness of the benchmark results. The heterogeneity analysis demonstrates that, in cities with underdeveloped public rail transit, the monocentric spatial development mode has a more obvious effect on reducing haze pollution. The results of the influence mechanism test show that the urban polycentric spatial development mode aggravates urban haze pollution, mainly by encouraging residents to travel by private transport, thereby increasing energy consumption. The obtained research results provide a sufficient basis for taking appropriate measures to govern haze pollution in Chinese cities from the perspective of polycentric spatial development mode. [ABSTRACT FROM AUTHOR]

Purpose: After major COVID-19 lockdown measures were suspended in 2021, E-scooter mobility regrew rapidly. In the meantime, multiple studies were published on the potential risks for e-scooter drivers and the necessity for wearing protective equipment. But did the drivers learn their lessons? Methods: We observed data of E-scooter-related accidents admitted to the emergency department of a level 1 German trauma center in the year 2021 and compared the data with our previous report (July 2019-July 2020). Results: N = 97 E-scooter-related accidents were included, marking a 50% increase when compared to the previous observation. Most patients were young adults (28.18 ± 1.13 years) with a notable shift towards a male population (25 vs. 63, p = 0.007). While the injury pattern remained unchanged, injury severity, reflected by a significant increase in shock room treatments (p = 0.005), hospital admissions (p = 0.45), and ICU admissions (p = 0.028), increased. Lastly, we report a higher injury severity of patients driving under the influence of alcohol, expressed by significant differences in hospital admissions, shock room treatments, ICU admissions, intracerebral bleeding (p < 0.0001), and injuries requiring surgery (p = 0.0017). Conclusion: The increase in injury severity and especially the substantial number of accidents due to driving under the influence of alcohol, are alarming for both trauma- and neurosurgeons. As the controversy surrounding the general use of E-scooters will continue, we urge representatives to intensify their efforts regarding prevention campaigns focusing on the potential dangers of E-scooters, especially when driving under the influence of alcohol. [ABSTRACT FROM AUTHOR]

The segregation of chromosomes depends on the centromere. Most species are monocentric, with the centromere restricted to a single region per chromosome. In some organisms, the monocentric organization changed to holocentric, in which the centromere activity is distributed over the entire chromosome length. However, the causes and consequences of this transition are poorly understood. Here, we show that the transition in the genus Cuscuta was associated with dramatic changes in the kinetochore, a protein complex that mediates the attachment of chromosomes to microtubules. We found that in holocentric Cuscuta species, the KNL2 genes were lost; the CENP-C, KNL1, and ZWINT1 genes were truncated; the centromeric localization of CENH3, CENP-C, KNL1, MIS12, and NDC80 proteins was disrupted; and the spindle assembly checkpoint (SAC) degenerated. Our results demonstrate that holocentric Cuscuta species lost the ability to form a standard kinetochore and do not employ SAC to control the attachment of microtubules to chromosomes. [ABSTRACT FROM AUTHOR]

The spatial structure of urban agglomerations affects the economic development and environmental conditions of urban agglomerations. Severe air pollution makes green development an empty talk, and how the spatial structure of urban agglomerations affects air pollution is an urgent problem to be solved in pursuit of high-quality economic development. The panel data of 20 urban agglomerations in China from 2002 to 2017 are used to test how the spatial structure of urban agglomerations affects regional PM2.5 concentration in resource misallocation mediation effect. The empirical results show that (1) most urban agglomerations are polycentric, and only Guanzhong, Poyang Lake Ring, Wuhan and Nanqin Beifang urban agglomerations are monocentric. (2) The spatial structure and PM2.5 concentration have U-shaped characteristics, with the inflection point of centrality equal to 1. To reduce PM2.5 concentration in polycentric urban agglomerations can be achieved by increasing the centrality, while the opposite is true for monocentric urban agglomerations. (3) Improving the resource allocation of urban agglomerations can reduce PM2.5 concentration. The spatial structure of urban agglomerations with a limited degree of centrality can improve the resource allocation of urban agglomerations and further reduce PM2.5 pollution. This also indicates to a certain extent that a reasonable spatial structure of urban agglomerations is conducive to optimizing resource allocation and improving air pollution.

The urban spatial structure is a reflection of urban development in the spatial dimension, and can have spillover effects on the economy, society, and environment. As air pollution gradually restricts eco-friendly development, it is critical to explore the relationship between urban spatial structure and air pollution. This study uses Chinese provinces and cities as subjects, and selects panel data from 2001 to 2016 to investigate the urban spatial structure as reflected by the proportions of the largest urban population in the province and the municipal districts in the city. Air pollution is measured in terms of PM2.5, which is an inversion transformation of remote sensing images. The relationship between urban spatial structure and air pollution is investigated using the spatial measurement model. The results are as follows: At the provincial level, the urban spatial structure and air pollution show a negative correlation. A monocentric spatial structure can help improve air pollution. At the municipal level, the urban spatial structure and air pollution show a U-shaped trend of first decreasing and then rising. Therefore, moderate, rather than excessive, urban agglomeration is required for the urban spatial structure at the municipal level.

Purpose: E-scooters are a new type of urban transportation utilized in Germany since June 2019, primarily in larger cities in the context of sharing offers. Such electrically operated standing scooters can be driven at a maximum speed of 20 km/h. A helmet is not mandatory. The aim of this prospective study is to document the injury patterns over the period of 1 year and compare our findings with already available data. Methods: Over a period of 1 year (July 2019–July 2020), data on E-scooter-related accidents treated at a level 1 trauma center of a major German city were prospectively documented. Injury patterns were analyzed, and epidemiological data evaluated. Results: Fifty-nine (35 female, 24 male) accidents were included in the observation period. Mean age of accident victims was 30.03 years (± 9.32). Alcohol influence at the time of accident was detected in 9 cases (15.25%). Many of the accident victims suffered multiple injuries. Most of the injuries were upper (50.84%) and lower extremity (47.45%) as well as craniofacial injuries (62.71%). A helmet was not worn in any of the cases. Conclusion: In the year following their introduction, E-scooter-related accidents have led to an additional burden on the emergency capacities of the involved University Hospital, especially in the summer months of 2019. Protective equipment is de facto not worn. Injuries to the extremities, head, and face were most common. None of the accident victims died. This coincides with results from other major cities in national and international comparison. A more intensive education about injury consequences of unprotected E-scooter use and the discussion of a possible obligation to wear a helmet and further protection equipment for the extremities should take place. [ABSTRACT FROM AUTHOR]

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The green economy has gained worldwide attention, especially in the urban agglomerations where population and economic activities are highly concentrated. However, what kind of urban agglomeration spatial structure is more conducive to promoting the green economy? No clear conclusions have been made. To bridge this gap, by employing the data of 16 urban agglomerations in China in 2003–2017 and a comprehensive analytic framework including dynamic panel threshold model, this paper studies the impact of urban agglomeration spatial structure on the green economy and the three subsystems of green economy to shed light on which kind of urban agglomeration spatial structure better drives the green economy. The main findings are shown below: (1) urban agglomeration spatial structural evolution is closely related to green economy, while in the research period, most urban agglomerations are not located in the optimal range of the spatial structure that drives the green economy. (2) Towards polycentric spatial structure is contributive to green economic growth; however, the excessively polycentric could not benefit green economy. (3) The evolution of urban agglomeration spatial structure exerts heterogeneous impacts on the three subsystems when green economy is decomposed into economic subsystem, resources subsystem, and environmental subsystem. Towards polycentric is more conducive to the improvement of economic subsystem and resource subsystem, while the tendency to monocentric drives the environmental subsystem. (4) Lastly, the conclusions enlighten the urban agglomeration development planning and spatial mode for approaching a better performance in green economy. [ABSTRACT FROM AUTHOR]

Understanding a city’s spatial structure is essential to understanding its potential for different development objectives. According to renowned planning consultant Alain Bertaud, a long-time Principal Urban Planner for the World Bank, some urban shapes are just more compatible with environmental and social objectives. Some city layouts, for example, are unfavorable to the development of public transit; others not only increase public transit’s efficiency but also reduce residential floor consumption. Because urban spatial structures are highly resilient and evolve only very slowly, says Bertaud, a city’s spatial structure significantly reduces the range of available development options. In this report, the author explores the link between cities’ spatial structures and their performance in terms of transit use and motorization, air pollution, and poverty. Comparing monocentric with polycentric structures, he finds that the type of urban structure often defines the success or failure of policy objectives in these contexts.

Over the last century, the urban spatial structure of cities has transformed dramatically from a traditional monocentric configuration to varying forms of decentralized organization. This paper reviews theory and empirical evidence to understand the urban morphology of jobs and land use within a city. Our survey highlights four broad insights: (i) The evolution of monocentric to polycentric centers have been accompanied by structural changes within the city. (ii) The internal geography of a city is an outcome of the trade-off between the pull from agglomeration economies and the push from congestion. (iii) The presence of externalities implies that the equilibrium spatial organization achieved by profit-maximizing firms may not necessarily be optimal. This justifies the role of public policy in addressing associated market failures. (iv) The productive edge and competitiveness of a city can be enhanced by introducing policies that increase the overall connectivity to take advantage of economic opportunities across the metropolitan area. The survey also puts together a wide range of policy instruments useful in closing the gap between equilibrium urban spatial structures and the optimal outcome. [ABSTRACT FROM AUTHOR]

Introduction: Several neurodegenerative brain proteinopathies, including Alzheimer's disease (AD), are associated with cerebral deposition of insoluble aggregates of α‐synuclein. Previous studies reported a trend toward increased cerebrospinal fluid (CSF) α‐synuclein (α‐syn) concentrations in AD compared with other neurodegenerative diseases and healthy controls. Methods: The pathophysiological role of CSF α‐syn in asymptomatic subjects at risk of AD has not been explored. We performed a large‐scale cross‐sectional observational monocentric study of preclinical individuals at risk for AD (INSIGHT‐preAD). Results: We found a positive association between CSF α‐syn concentrations and brain β‐amyloid deposition measures as mean cortical standard uptake value ratios. We demonstrate positive correlations between CSF α‐syn and both CSF t‐tau and p‐tau181 concentrations. Discussion: Animal models presented evidence, indicating that α‐syn may synergistically and directly induce fibrillization of both tau and β‐amyloid. Our data indicate an association of CSF α‐syn with AD‐related pathophysiological mechanisms, during the preclinical phase of the disease. [ABSTRACT FROM AUTHOR]

Based on a study in four Norwegian cities (Oslo, Stavanger/Sandnes, Bergen and Trondheim) differing in size and centre structure, this article illuminates how residential and workplace location, localarea density and transit accessibility influence different aspects of travel behaviour. We find strong effects of residential and workplace distance to the city centre on overall driving distances and commuting distances. We also find clear effects of local area densities around residences and workplaces on the choice of car as a travel mode, along with less pronounced effects of the distance from dwellings and workplaces to the city centre. In the cities with the best developed transit provision, we also see clear effects of transit accessibility at the residence on the propensity of choosing the car as travel mode. The results provide strong support of Norwegian national policies of urban densification as a planning strategy to curb the growth in urban motoring. However, although the influences of urban structure on travel show many similarities across the four cities, there are also important differences reflecting variations in centre structure (predominantly mono- or polycentric) and population size. The magnitude of the influences of various urban structural characteristics on travel behaviour are thus highly context-dependent. [ABSTRACT FROM AUTHOR]

One challenge of studying how urbanization impacts ecological patterns and processes is to characterize 'urban' and thus evaluate and determine measures to quantify urbanization gradients. A comprehensible quantification of urbanization gradients would provide a common context allowing comparability, better generalizations and informing our quest to achieve a more sustainable urban form. We aimed to determine a set of urbanization measures useful for quantifying the urbanization gradient of two European cities (Vienna and Amsterdam) and assessed their sensitivity to scale. We also evaluated whether a common subset of measures could be identified and whether the monocentric city structure was adequate. We calculated 17 urbanization measures identified from the literature and limited by availability and comparability and used cluster and factor analysis. Although, the urbanization gradient for Vienna and Amsterdam was characterized by four clusters, their spatial structure differed as indicated by their departure from the monocentric city model. Key urbanization measures did not coincide entirely for both cities and depended on the scale of analysis. Opting for a multivariate approach instead of using solely one measure for quantifying urbanization gradients and taking into consideration scale sensitivity would allow a better representation of the urban complexity, greatly improve the accuracy of characterized gradients and advance our understanding of the ecological impacts of urbanization and cities' potential to achieve sustainability. [ABSTRACT FROM AUTHOR]

Based on a study in the Greater Oslo and Greater Stavanger urban areas in Norway, this paper employs quantitative and qualitative research methods to investigate the influences of residential location and neighborhood characteristics on car driving distances. Cross-sectional and quasi-longitudinal analyses show that built environment characteristics — especially the distance from the dwelling to the main city center — influence driving distances in both urban areas. In Stavanger, the impact of inward moving seems to be larger than that of outward moving, possibly reflecting self-selection to the inner city. In the relatively monocentric Greater Oslo, the distance to the city center has a stronger impact on weekday driving than on weekend driving. In the more polycentric Greater Stavanger, where the importance of downtown as a destination for commuting is weaker, the distance to the city center has similar effects on weekday and weekend driving. In Greater Stavanger, distance to the secondary center Sandnes also plays a role although the impact is small. Population density and job density have impacts in Greater Oslo but not in Greater Stavanger, where we instead find a weak effect of local-area job surplus. There is no tendency toward compensatory increased weekend driving among inner-city dwellers in either Greater Oslo or Greater Stavanger.

Two end-stage renal disease ( ESRD) risk calculators were recently developed by Grams et al., and Ibrahim et al. to calculate ESRD risk before donation among living kidney donors. However, those calculators have never been studied among potential donors for whom donation was refused due to medical contraindications and compared to a group of donors. We compared 15-year and lifetime ESRD risk of donors and nondonors due to medical cause as estimated by those two calculators. Nondonors due to medical cause ( n = 27) had a significantly higher 15-year ESRD risk compared to donors ( n = 288) with both calculators (0.25 vs. 0.14, P < 0.001 for that developed by Grams et al. and 2.21 vs. 1.43, P = 0.002 for that developed by Ibrahim et al.). On the contrary, lifetime ESRD risk was not significantly different between the two groups. At both times (15 years and lifetime), we observed a significant overlap of ESRD risk between the two groups. ESRD risk calculators could be complementary to standard screening strategy but cannot be used alone to accept or decline donation. [ABSTRACT FROM AUTHOR]

City planners are increasingly captivated by the possibilities of transforming urban spatial structures as an important strategy for reducing heat island intensity. This study addresses the mixed findings of polycentric urban spatial structures on surface urban heat island intensity, using a multiple regression method and pathway analysis for the city region and city proper in China. We found that the polycentric spatial structure can reduce the surface urban heat island intensity at the scale of both the city region and city proper, although the reduction was economically insignificant at the city region scale. Path analysis explained the reduction in surface urban heat island intensity in the city proper: polycentric structures disperse industrial firms to the "rural" areas and centralizes green spaces in the "urban" areas. Our findings may serve as references for policymakers when optimizing urban spatial structures to improve the thermal environment. • The polycentric structure can reduce the surface urban heat island intensity. • The polycentric structure disperses industrial firms to the suburbs. • The polycentric structure centralizes green spaces into the downtown area. • The polycentric city proper has a lower surface urban heat island intensity. [ABSTRACT FROM AUTHOR]

The spatial structure of urban agglomerations affects the economic development and environmental conditions of urban agglomerations. Severe air pollution makes green development an empty talk, and how the spatial structure of urban agglomerations affects air pollution is an urgent problem to be solved in pursuit of high-quality economic development. The panel data of 20 urban agglomerations in China from 2002 to 2017 are used to test how the spatial structure of urban agglomerations affects regional PM2.5 concentration in resource misallocation mediation effect. The empirical results show that (1) most urban agglomerations are polycentric, and only Guanzhong, Poyang Lake Ring, Wuhan and Nanqin Beifang urban agglomerations are monocentric. (2) The spatial structure and PM2.5 concentration have U-shaped characteristics, with the inflection point of centrality equal to 1. To reduce PM2.5 concentration in polycentric urban agglomerations can be achieved by increasing the centrality, while the opposite is true for monocentric urban agglomerations. (3) Improving the resource allocation of urban agglomerations can reduce PM2.5 concentration. The spatial structure of urban agglomerations with a limited degree of centrality can improve the resource allocation of urban agglomerations and further reduce PM2.5 pollution. This also indicates to a certain extent that a reasonable spatial structure of urban agglomerations is conducive to optimizing resource allocation and improving air pollution., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

This study is an attempt to develop an internationally applicable compact city index that measures the performance of physical urban forms with regard to compact city policies. Based on key characteristics of the compact city that are high density, mixed land-use, and public transport systems, we formulate a new index called ‘compact city index’ (CCI) to assess urban compactness of populations, facilities and amenities centred on public transport systems at both community and city levels. Then sensitivity analyses follow simulating different scenarios varying hypothetical urban forms to check a dominant bias to specific variables in the CCI equation. Finally four types of CCI, in different measurements of time and distance, are applied to 41 middle-sized Japanese cities. It is found that cities can achieve urban compactness in the time aspect by utilisation of well-networked public transport systems, even though physical urban forms of those cities are largely sprawled. [ABSTRACT FROM PUBLISHER]

The coral species Leptoseris troglodyta sp. n. (Scleractinia, Agariciidae) is described as new to science. It is the first known azooxanthellate shallow-water agariciid and is recorded from the ceilings of caves at 5-35 m depth in West Pacific coral reefs. The corals have monocentric cup-shaped calices. They may become colonial through extramural budding from the basal coenosteum, which may cause adjacent calices to fuse. The size, shape and habitat of L. troglodyta are unique compared to other Leptoseris species, many of which have been recorded from mesophotic depths. The absence of zooxanthellae indicates that it may survive well in darkness, but endolithic algae in some corals indicate that they may be able to get some light. The presence of menianes on the septal sides, which may help to absorb light at greater depths in zooxanthellate corals, have no obvious adaptive relevance in the new species and could have been inherited from ancestral species that perhaps were zooxanthellate. The new species may be azooxanthellate as derived through the loss of zooxanthellae, which would be a reversal in Leptoseris phylogeny. [ABSTRACT FROM AUTHOR]

A common approach to modeling population density gradients across a city is to adjust the specification of a selected set of mathematical functions to achieve the best fit to an urban place’s empirical density values. In this paper, we employ a spatial regression approach that takes into account the spatial autocorrelation latent in urban population density. We also use a Minkowskian distance metric instead of Euclidean or network distance to better describe spatial separation. We apply our formulation to the 20 largest metropolitan areas in the US according to the 2000 census, using block group level data. The general model furnishes good descriptions for both monocentric and polycentric cities. [ABSTRACT FROM AUTHOR]

Canonical meiosis is characterized by two sequential rounds of nuclear divisions following one round of DNA replication-reductional segregation of homologous chromosomes during the first division and equational segregation of sister chromatids during the second division. Meiosis in an inverted order of two nuclear divisions-inverted meiosis has been observed in several species with holocentromeres as an adaptive strategy to overcome the obstacle in executing a canonical meiosis due to the holocentric chromosome structure. Recent findings of co-existence of inverted and canonical meiosis in two monocentric organisms, human and fission yeast, suggested that inverted meiosis could be common and also lead to the puzzle regarding the mechanistic feasibility for executing two meiosis programs simultaneously. Here, we discuss apparent conflicts for concurrent canonical meiosis and inverted meiosis. Furthermore, we attempt to provide a working model that may be compatible for both forms of meiosis., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Several neurodegenerative brain proteinopathies, including Alzheimer's disease (AD), are associated with cerebral deposition of insoluble aggregates of α-synuclein. Previous studies reported a trend toward increased cerebrospinal fluid (CSF) α-synuclein (α-syn) concentrations in AD compared with other neurodegenerative diseases and healthy controls., Methods: The pathophysiological role of CSF α-syn in asymptomatic subjects at risk of AD has not been explored. We performed a large-scale cross-sectional observational monocentric study of preclinical individuals at risk for AD (INSIGHT-preAD)., Results: We found a positive association between CSF α-syn concentrations and brain β-amyloid deposition measures as mean cortical standard uptake value ratios. We demonstrate positive correlations between CSF α-syn and both CSF t-tau and p-tau 181 concentrations., Discussion: Animal models presented evidence, indicating that α-syn may synergistically and directly induce fibrillization of both tau and β-amyloid. Our data indicate an association of CSF α-syn with AD-related pathophysiological mechanisms, during the preclinical phase of the disease., (Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.)