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. 

This article explored mineral resources and their relation to structural settings in the Central Eastern Desert (CED) of Egypt. Integration of remote sensing (RS) with aeromagnetic (AMG) data was conducted to generate a mineral predictive map. Several image transformation and enhancement techniques were performed to Landsat Operational Land Imager (OLI) and Shuttle Radar Topography Mission (SRTM) data. Using band ratios and oriented principal component analysis (PCA) on OLI data allowed delineating hydrothermal alteration zones (HAZs) and highlighted structural discontinuity. Moreover, processing of the AMG using Standard Euler deconvolution and residual magnetic anomalies successfully revealed the subsurface structural features. Zones of hydrothermal alteration and surface/subsurface geologic structural density maps were combined through GIS technique. The results showed a mineral predictive map that ranked from very low to very high probability. Field validation allowed verifying the prepared map and revealed several mineralized sites including talc, talc-schist, gold mines and quartz veins associated with hematite. Overall, integration of RS and AMG data is a powerful technique in revealing areas of potential mineralization involved with hydrothermal processes.

The need for global energy conservation has become more urgent because of the negative effects of excessive energy use, such as higher fuel consumption, greater environmental pollution, and depletion of the ozone layer. There has been a significant increase in the demand for central and high-capacity household air conditioning systems in Muscat in recent years. The need for this is influenced by factors such as arid climate, increasing temperatures, air pollution, and population increase. As a result, there has been a significant increase in electricity use, putting a strain on power resources. To tackle this difficulty, the incorporation of solar collectors as supplementary thermal compressors in air conditioning systems offers a chance to utilise renewable energy sources. The objective of this hybrid technique is to enhance the effectiveness of cooling systems, hence minimising the need for electricity and lowering the release of environmental pollutants.

The developmental dilemma of infant and toddler care is examined from a family perspective, and in-depth analyses of infant and toddler care are conducted using Family Systems Theory and Cultural Capital Theory,which are essential to the holistic development of children, the balance between family and work, and the sustainable development of society and the economy.The developmental dilemmas of infant and toddler care are discussed in depth from the family perspective, and solutions are proposed accordingly. By applying family systems theory and cultural capital theory to analyze the root causes and influencing factors of the problem, it provides useful thoughts and suggestions for improving infant and toddler care practices.

A topic of current interest in forestry science concerns the regeneration of degraded forests and areas. Within this topic, an important aspect refers to the time that different forests take to recover their original levels of diversity and other characteristics that are key to resume their functioning as ecosystems. The present work focuses on the premontane rainforests of the central Peruvian rainforest, in the Chanchamayo valley, Junín, between 1,000 and 1,500 masl. A total of 19 Gentry Transects of 2 × 500 m, including all woody plants ≥2.5 cm diameter at breast height were established in areas of mature forests, and forests of different ages after clear-cutting without burning. Five forest ages were considered, 5-10, 20, 30, 40 and ≥50 years. The alpha-diversity and composition of the tree flora under each of these conditions was compared and analyzed. It was observed that, from 40 years of age, Fisher’s alpha-diversity index becomes quite similar to that characterizing mature forests; from 30 years of age, the taxonomic composition by species reached a similarity of 69–73%, like those occurring in mature forests. The characteristic botanical families, genera and species at each of the ages were compared, specifying that as the age of the forest increases, there are fewer shared species with a high number of individuals. Early forests, up to 20 years of age, are characterized by the presence of Piperaceae; after 30 years of age, they are characterized by the Moraceae family.

Physical sampling of water on site is necessary for various applications like drinking water quality checking in lakes and checking for contaminants in freshwater systems. The use of water surface vehicles is a promising technology for monitoring and sampling water bodies, and they offer several advantages over traditional monitoring methods. This project involved designing and integrating a drone controller, water collection sampling contraption unit, and a surveillance camera system into a water surface vehicle (WSV). The drone controller unit is used to operate the boat from the starting location until the location of interest and then back to the starting location. The drone controller has an autopilot system where the operator can set a course and be able to travel following the path set, whereas the WSV will fight the external forces to keep itself in the right position. The water collection sampling unit is mounted onto WSV so when it travels to the location, it can start collecting and holding water samples until it returns to the start location. The field of view (FOV) surveillance camera helps the operator to observe the surrounding location during the operation. Experiments were conducted to determine the operational capabilities of the robot boat at the Ayer Keroh Lake. The water collection sampling contraption unit collected samples from 44 targeted areas of the lake. The comprehensive examination of 14 different water quality parameters were tested from the collected water samples provides insights into the factors influencing the pollution and observation of water bodies. The successful design and development of a water surface surveillance and pollution tracking vehicle marks the key achievements of this study. The developed collection and surveillance unit holds the potential for further refinement and integration onto various other platforms. They are offering valuable assistance in water body management, coastal surveillance, and pollution tracking. This system opens up new possibilities for comprehensive water body assessments, contributing to the advancement of sustainable and efficient water testing. Through careful sampling efforts, a thorough overview of the substances presents in the water collected from Ayer Keroh Lake has been compiled. This in-depth analysis provides important insights into the lake’s current condition, offering valuable information about its ecological health.