This paper uses Public Choice analysis to examine the case for and experience with Public-Private Partnerships (PPPs). A PPP is a contractual platform which connects a governmental body and a private entity. The goal is to provide a public sector program, service, or asset that would normally be provided exclusively by a public sector entity. This paper focuses on PPPs in developed countries, but it also draws on studies of PPPs in developing countries. The economics literature generally defines PPPs as long-term contractual arrangements between a public authority (local or central government) and a private supplier for the delivery of services. The private sector supplier takes responsibility for building infrastructure components, securing financing of the investment, and then managing and maintaining this facility.

However, in addition to those formed through contracts, PPPs may take other forms such as those developed in response to tax subvention or coercion, as in the case of regulatory mandates. A key element of PPP is that the private partner takes on a significant portion of the risk through a schedule of specified remuneration, contingency payments, and provision for dispute resolution. PPPs typically are long-term arrangements and involve large corporations on the private side, but may also be limited to specific phases of a project.

The types of PPPs discussed in this paper exclude arrangements which may result from government mandates such as the statutory emission mandates imposed on automobile manufacturers and industrial facilities (e.g., power plants). It also excludes PPP-like organizations resulting from US section 501(c)(3) of the Internal Revenue Code, which provides tax subsidies for certain public charities, scientific research organizations, and organizations whose goals are to prevent cruelty to animals or erect public monuments at no expense to the government. This paper concludes that an array of Public Choice tools are applicable to understanding the emergence, success, or failure of PPPs. Several short case studies are provided to illustrate the practicalities of PPPs. 

Salicylaldehyde imine transition metal catalyst is a kind of olefin polymerization catalyst that is widely used in the coordination of salicylaldehyde imine ligand and pre-transition metal. Salicylaldehyde imine ligands have the characteristic of easily inserting different substituents via organic synthesis. Therefore, the regulation of the polymerization activity, polymerization product, and product distribution can be achieved by changing the steric hindrance effect, the electronic effect, and the number of metal active sites near the catalytic active center. The development status of the transition metal catalyst of salicylaldehyde imide was summarized in this paper. The influence of the ligand structure of the salicylaldehyde imide transition metal catalyst on the catalytic performance, which involved the high selectivity of ethylene trimerization, ethylene/α-olefin, polar monomer copolymerization, ethylene polymerization production, ultra-high molecular weight polyethylene, and many other areas of olefin polymerization, was elaborated, providing references for further study and industrial applications of this catalyst.

This study uses the opening of the new Mass Rapid Transit (MRT) in stages between 2010 and 2012 in Singapore as the exogenous event to empirically test the impact of the new Circle Line (CL) on housing wealth. Applying a "differences-in-differences" approach to the non-landed private housing transaction data covering the period from 2009 to 2013, we find that the average housing prices increase by 1.6% in the post-opening of the CL. We find significant capitalization of the new CL into housing prices, especially households living within a 400-meter radius (the treatment zone) from the closest MRT stations on the CL. The treatment effects that are measured by the "marginal willingness to pay" for houses located within the treatment zone is 13.2% relative to houses located outside the treatment zone. The new CL opening creates an estimated S$1.23 billion housing wealth effects for households living in close proximity to the CL MRT stations. However, we do not find significant "anticipative" effects on house prices in the six-month window prior to the opening of CL. The strongest treatment effect is found after the opening of the phase 1 of CL, and the treatment intensity declines in phases 2 and 3 of the CL opening.

The whole world is in a fuel crisis nearly approaching exhaustion, with climate change knocking at our doorsteps. In the fight against global warming, one of the principle components that demands technocratic attention is Transportation, not just as a significant contributor to atmospheric emissions but from a much broader perspective of environmental sustainability. 

From the traditional technocratic aspect of transport planning, our epiphany comes in the form of Land Use integrated sustainable transport policy in which Singapore has been a pioneer, and has led the way for both developed and developing nations in terms of mobility management. We intend to investigate Singapore’s Transport policy timeline delving into the past, present and future, with a case by case analysis for varying dimensions in the present scenario through selective benchmarking against contemporary cities like Hong Kong, London and New York. The discussions will include themes of modal split, land use policy, vehicular ownership, emission policy, parking policy, safety and road traffic management to name a few. A visualization of Singapore’s future in transportation particularly from the perspective of automated vehicles in conjunction with last mile solutions is also detailed. 

Clinical/methodological problem: The identification of clinically significant prostate carcinomas while avoiding overdiagnosis of low-malignant tumors is a challenge in routine clinical practice. Standard radiologic procedures: Multiparametric magnetic resonance imaging (MRI) of the prostate acquired and interpreted according to PI-RADS (Prostate Imaging Reporting and Data System Guidelines) is accepted as a clinical standard among urologists and radiologists. Methodological innovations: The PI-RADS guidelines have been newly updated to version 2.1 and, in addition to more precise technical requirements, include individual changes in lesion assessment. Performance: The PI-RADS guidelines have become crucial in the standardization of multiparametric MRI of the prostate and provide templates for structured reporting, facilitating communication with the referring physician. Evaluation: The guidelines, now updated to version 2.1, represent a refinement of the widely used version 2.0. Many aspects of reporting have been clarified, but some previously known limitations remain and require further improvement of the guidelines in future versions.