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This paper studies the impacts of Madrid-Seville High-Speed Rail (HSR) on land-cover change in the five HSR connected cities – Madrid, Ciudad Real, Puertollano, Cordoba, and Seville. The analysis period ranges from 1991 to 2006. The study finds that, in the Madrid-Seville region, the land development process concentrates mostly toward the two largest cities, Madrid and Seville, while other smaller HSR served cities are also benefited. The process of land development in each city varies largely. HSR contributes more to Ciudad Real and Cordoba than to Puertollano, with booming urban development in the former two cities. To study the accessibility impacts of HSR, binary discrete choice models are adopted. The results suggest that, the land development in smaller cities can be mainly explained by the improvement of regional accessibility and population growth. However, to model the urban development process in Madrid and Seville, the inputs with only accessibility and population are not sufficient. [ABSTRACT FROM PUBLISHER]

We evaluated the predictive value of [18F]fluoro-2-deoxy- d-glucose positron emission tomography (FDG-PET) for clinical outcome such as progression-free survival (PFS) and overall survival (OS) in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) prior to and after autologous stem cell transplant (ASCT). FDG-PET/computed tomography (CT) was performed in 39 consecutive patients with relapsed/refractory DLBCL scheduled for ASCT. The median follow-up of surviving patients was 3 years (range 19-66 months). Both pre- and post-ASCT, FDG-PET findings were strongly correlated with PFS and OS ( p < 0.005). The 2-year PFS estimates for FDG-negative versus -positive patients were 84.8% vs. 36.8% (pre-) and 81.1% vs. 13.3% (post-). The 2-year OS estimates in these groups were 95.5% vs. 68.3% (pre-) and 92.7% vs. 57.1% (post-). Patients were classified into three groups according to FDG-PET results before and after ASCT. The median PFS was significantly lower in the +/+ group (13.0 months) as compared with the +/− group (31.0 months, p = 0.021) and the −/− group ( p = 0.000). The regression model showed that the predictive value of FDG-PET before ASCT owed its significance to a very high hazard ratio between patients with positive and negative imaging ( p < 0.01). FDG-PET prior to and following ASCT in patients with relapsed or refractory DLBCL contains prognostic information on long-term clinical outcome. [ABSTRACT FROM AUTHOR]

Facing rapid motorization, many Chinese municipalities are implementing policies that restrict car ownership or use. However, there is significant variation in terms of which cities adopt these policies and when. This research systematically investigates what factors prompt local governments in China to adopt these car restriction policies. We collect a database of car restriction policies as well as economic, demographic, land use, and transportation indicators for 287 Chinese municipalities from 2001 to 2014. We adopt a mixed methods approach that combines a qualitative investigation of stated objectives and legislative precedent within policy documents with a quantitative duration model of policy adoption. We find that the adoption of comprehensive car ownership and use restriction policies across Chinese cities primarily responds to local air pollution and secondarily to car ownership and congestion. Policy adoption additionally responds to local subway line constructions. Local economic power and population size do not effectively explain policy adoption. Idiosyncratic effects at provincial or city levels are important, although the underlying mechanisms by which these network effects manifest remain unclear. Broadly, our findings suggest that problem solving and network effects both contribute to the adoption of car restriction policies across China's cities and that the legal policy documents reliably illustrate the motivations of these policies. [ABSTRACT FROM AUTHOR]

One of the main features in mobility sharing applications is the exposure of personal data provided to the system. Transportation and location data can reveal personal habits, preferences, and behaviors, and riders could be keen not to share the exact location of their origin and/or destination. But what is the price of privacy in terms of decreased efficiency of a mobility sharing system? In this paper we address the privacy issues under this point of view, and show how location privacy-preserving techniques could affect the performance of mobility-sharing applications, in terms of both system efficiency and quality of service. To this extent, we first apply different data-masking techniques to anonymize geographical information, and then compare the performance of shareability network-based trip-matching algorithms for ride-sharing, applied to real data and to privacy-preserving data. The goal of the paper is to evaluate the performance of mobility-sharing, privacy-preserving systems, and to shed light on the trade-off between data privacy and its costs. The results show that the total traveled distance increase due to the introduction of data privacy could be bounded if users are willing to spend (or "pay") for more time in order to share a trip, meaning that data location privacy affects both efficiency and quality of service. [ABSTRACT FROM AUTHOR]

Problem, research strategy, and findings: Local government policies could affect how autonomous vehicle (AV) technology is deployed. In this study we examine how municipalities are planning for AVs, identify local characteristics that are associated with preparation, and describe what effects bureaucrats expect from the vehicles. We review existing plans of the 25 largest U.S. cities and survey transportation and planning officials from 120 cities, representative of all municipalities with populations larger than 100,000. First, we find that few local governments have begun planning for AVs. Second, cities with larger populations and higher population growth are more likely to be prepared. Third, although local officials are optimistic about the technology and its potential to increase safety while reducing congestion, costs, and pollution, more than a third of respondents worried about AVs increasing vehicle miles traveled and sprawl while reducing transit ridership and local revenues. Those concerns are associated with greater willingness to implement AV regulations, but there is variation among responses depending on political ideology, per capita government expenditures, and population density. Takeaway for practice: Municipal governments' future approaches to AV preparation will likely depend on the characteristics of city residents and local resources. Planners can maximize policy advancement if they work with officials in other cities to develop best practices and articulate strategies that overlap with existing priorities, such as reducing pollution and single-occupancy commuting. [ABSTRACT FROM AUTHOR]

A new generation of bike-sharing services without docking stations is currently revolutionizing the traditional bike-sharing market as it dramatically expands around the world. This study aims at understanding the usage of new dockless bike-sharing services through the lens of Singapore's prevalent service. We collected the GPS data of all dockless bikes from one of the largest bike sharing operators in Singapore for nine consecutive days, for a total of over 14 million records. We adopted spatial autoregressive models to analyze the spatiotemporal patterns of bike usage during the study period. The models explored the impact of bike fleet size, surrounding built environment, access to public transportation, bicycle infrastructure, and weather conditions on the usage of dockless bikes. Larger bike fleet is associated with higher usage but with diminishing marginal impact. In addition, high land use mixtures, easy access to public transportation, more supportive cycling facilities, and free-ride promotions positively impact the usage of dockless bikes. The negative influence of rainfall and high temperatures on bike utilization is also exhibited. The study also offered some guidance to urban planners, policy makers, and transportation practitioners who wish to promote bike-sharing service while ensuring its sustainability. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) imaging offers physiological and biological information through thein vivodistribution of PET agents for disease diagnosis, therapy monitoring and prognosis evaluation. Due to the unique structural characteristics allowing for facile modification of targeting ligands and radionuclides, dendrimers can be served as a versatile scaffold to build up various PET imaging agents, and significant breakthroughs have been made in this field over the past decades. This review focuses on the recent advances in dendrimer-based contrast agents for PET imaging of cancer, cardiovascular and other diseases. In particular, radiolabeling strategies for different PET isotopes are described in detail. Several challenges involved in clinical translation of radiolabeled dendrimers are also discussed. [ABSTRACT FROM AUTHOR]

This research investigates the usage of smart devices and time at bus stops and on buses in Vancouver, Canada. Using passive observations and self-reported surveys mainly from college students, the majority of passengers were found to use their travel time actively. Most of the observed active activities are associated with the usage of smart devices. However, while the possession of smart devices is prevalent, less than one-third of passengers used them during travel. A variety of environmental and trip factors, personal attributes, and past experiences influence the usage of smart devices. Research also found that smart devices encourage multitasking. [ABSTRACT FROM AUTHOR]

Fucosylated glycosaminoglycan (FG) from sea cucumbers has been reported to have anticoagulant effects via targeting intrinsic tenase. However, FG from natural source also potentially poses risks due to its FXIIa activation and platelet aggregating effects. Here, we found that the effect of FG on human platelet aggregation depended on both the sulfation pattern and chain length. FGs with higher content of Fuc2S4S and larger molecular weight (≥14 kD) had stronger activity. Both platelet aggregation and P-selectin expression induced by TaFG (an FG from Thelenota ananas) were decreased as the molecular weight reduced. Ticagrelor, aspirin and wortmannin completely blocked the secretion (ADP) but only partially blocked the aggregation induced by TaFG. Tirofiban an αIIbβ3 antagonist however potently inhibited both the secretion and aggregation, with IC50 of 6.01 ± 1.1.97 nM. Furthermore, TaFG could bind to human αIIbβ3 with high affinity, and the affinities of two FGs were paralleled with their activity in platelet aggregation or activation. These results indicated that αIIbβ3 played an important role in TaFG-induced platelet aggregation which was mediated by PI3K, and that platelet secretion was required for the amplification of aggregation. [ABSTRACT FROM AUTHOR]

The identification of markers expressed by pathological cells or their microenvironment would help to distinguish such cells from the normal tissues. The strategies derived from this theory can be a promising modality for imaging and treating diseases. LyP-1, a tumor homing peptide, can selectively bind to its receptor p32 protein overexpressed in various tumor-associated cells and atherosclerotic plaque macrophages. During recent decades, multiple types of LyP-1-based imaging probes and drug delivery systems have been designed and developed for diagnostic and therapeutic applications. This review first introduces LyP-1 and its receptor p32, as well as its homing, internalization and proapoptotic properties. Next, we highlight recent studies focusing on the applications of LyP-1-based strategies in the diagnosis and treatment of tumors, metastatic lesions, and atherosclerotic plaques. Finally, several limitations in the clinical translation of LyP-1-based bioconjugates are summarized. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis, characterization and utilization of 99mTc-labelled polyethylenimine-entrapped gold nanoparticles (99mTc-Au-PENPs) for dual mode single-photon emission computed tomography/computed tomography (SPECT/CT) imaging applications. Polyethylenimine (PEI) was selected as a platform to conjugate with diethylene triamine pentacetate acid (DTPA) and polyethylene glycol monomethyl ether to synthesize Au PENPs, followed by acetylation or hydroxylation modification of the remaining PEI surface amine groups and radiolabelling of 99mTc. The generated multifunctional 99mTc-Au-PENPs with different surface groups (acetyl or hydroxyl) were characterized via different methods. The Au PENPs before 99mTc labelling are colloidally stable, haemocompatibility and noncytotoxic at an Au concentration up to 100 μM. The 99mTc-labelled Au PENPs exhibit high radiochemical purity, good stability and SPECT/CT imaging performance of different organs and lymph node. The designed strategy to use the radionuclide labelling technique and PEI-facilitated versatile nanoplatform may be extended to develop various novel nanoprobes for precision imaging applications. [ABSTRACT FROM AUTHOR]

Non-invasive imaging of apoptosis in tumors induced by chemotherapy is of great value in the evaluation of therapeutic efficiency. In this study, we report the synthesis, characterization, and utilization of radionuclide technetium-99m (99mTc)-labeled dendrimer-entrapped gold nanoparticles (Au DENPs) for targeted SPECT/CT imaging of chemotherapy-induced tumor apoptosis. Generation five poly(amidoamine) (PAMAM) dendrimers (G5.NH2) were sequentially conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), polyethylene glycol (PEG) modified duramycin, PEG monomethyl ether, and fluorescein isothiocyanate (FI) to form the multifunctional dendrimers, which were then utilized as templates to entrap gold nanoparticles. Followed by acetylation of the remaining dendrimer surface amines and radiolabeling of 99mTc, the SPECT/CT dual mode nanoprobe of tumor apoptosis was constructed. The developed multifunctional Au DENPs before and after 99mTc radiolabeling were well characterized. The results demonstrate that the multifunctional Au DENPs display favorable colloidal stability under different conditions, own good cytocompatibility in the given concentration range, and can be effectively labeled by 99mTc with high radiochemical stability. Furthermore, the multifunctional nanoprobe enables the targeted SPECT/CT imaging of apoptotic cancer cells in vitro and tumor apoptosis after doxorubicin (DOX) treatment in the established subcutaneous tumor model in vivo. The designed duramycin-functionalized Au DENPs might have the potential to be employed as a nanoplatform for the detection of apoptosis and early tumor response to chemotherapy. [ABSTRACT FROM AUTHOR]

Non-invasive imaging of apoptosis in tumors induced by chemotherapy is of great value in the evaluation of therapeutic efficiency. In this study, we report the synthesis, characterization, and utilization of radionuclide technetium-99m (99mTc)-labeled dendrimer-entrapped gold nanoparticles (Au DENPs) for targeted SPECT/CT imaging of chemotherapy-induced tumor apoptosis. Generation five poly(amidoamine) (PAMAM) dendrimers (G5.NH2) were sequentially conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), polyethylene glycol (PEG) modified duramycin, PEG monomethyl ether, and fluorescein isothiocyanate (FI) to form the multifunctional dendrimers, which were then utilized as templates to entrap gold nanoparticles. Followed by acetylation of the remaining dendrimer surface amines and radiolabeling of 99mTc, the SPECT/CT dual mode nanoprobe of tumor apoptosis was constructed. The developed multifunctional Au DENPs before and after 99mTc radiolabeling were well characterized. The results demonstrate that the multifunctional Au DENPs display favorable colloidal stability under different conditions, own good cytocompatibility in the given concentration range, and can be effectively labeled by 99mTc with high radiochemical stability. Furthermore, the multifunctional nanoprobe enables the targeted SPECT/CT imaging of apoptotic cancer cells in vitro and tumor apoptosis after doxorubicin (DOX) treatment in the established subcutaneous tumor model in vivo. The designed duramycin-functionalized Au DENPs might have the potential to be employed as a nanoplatform for the detection of apoptosis and early tumor response to chemotherapy. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis, characterization and utilization of 99mTc-labelled polyethylenimine-entrapped gold nanoparticles (99mTc-Au-PENPs) for dual mode single-photon emission computed tomography/computed tomography (SPECT/CT) imaging applications. Polyethylenimine (PEI) was selected as a platform to conjugate with diethylene triamine pentacetate acid (DTPA) and polyethylene glycol monomethyl ether to synthesize Au PENPs, followed by acetylation or hydroxylation modification of the remaining PEI surface amine groups and radiolabelling of 99mTc. The generated multifunctional 99mTc-Au-PENPs with different surface groups (acetyl or hydroxyl) were characterized via different methods. The Au PENPs before 99mTc labelling are colloidally stable, haemocompatibility and noncytotoxic at an Au concentration up to 100 μM. The 99mTc-labelled Au PENPs exhibit high radiochemical purity, good stability and SPECT/CT imaging performance of different organs and lymph node. The designed strategy to use the radionuclide labelling technique and PEI-facilitated versatile nanoplatform may be extended to develop various novel nanoprobes for precision imaging applications. [ABSTRACT FROM AUTHOR]