A Critique of Quasiexperimental and Statistical Controls for Measuring Program Effects: Application to Urban Growth Control

In this paper we wish to discuss some aspects of a particular system approach in urban planning. An attempt has been made to explain the meaning of the first principal factor (Hotelling, 1933) in the verification of a set of supposed urban characteristics. The same factor model has been used in the subsequent measurement of the degree of urbanity in each municipal territory in Flanders. In mapping the results we have also attempted to verify some growth and communication theories for the Flanders case. Finally, the basic point of the paper is the detection of time-lag effects which create gaps between the slower development of more rigid environment elements, with which the planner is concerned, and the more quickly adapting elements—a time lag which could indicate urgent planning areas.

Download Full-text

Analysis of an Urban Development Boundary Policy in China Based on the IAD Framework

Land ◽

10.3390/land10080855 ◽

2021 ◽

Vol 10 (8) ◽

pp. 855

Author(s):

Jiaojiao Luo ◽

Wei Wang ◽

Yuzhe Wu ◽

Yi Peng ◽

Linlin Zhang

Keyword(s):

Urban Development ◽

Urban Sprawl ◽

Central Government ◽

Growth Control ◽

Industrial Land ◽

Land Transfer ◽

Institutional Analysis And Development ◽

Urban Growth Control ◽

Policy Problems ◽

Iad Framework

Although urban growth control policies are widely adopted to help sustainable development in various countries, including China, few studies have been conducted to investigate the effectiveness and optimization of such policies in Chinese cities. Hangzhou, China, was chosen for this study as the research object, where the local authorities manage the urban sprawl via an urban development boundary policy. The institutional analysis and development (IAD) framework was employed to identify the conflicts between the central government and the local government as well as the developers and homebuyers in the formal/informal stage. The analysis shows that, with the implementation of the policy, problems such as fiscal crises, property inflation, and illegal construction will appear as a result of actors’ interactions. The study also highlights that industrial land transfer inside the boundary should be controlled in a reasonable range and that a land value tax should be introduced during the implementation of the urban development boundary policy.

Download Full-text

Quantitative EM of gap junction distribution in mutant drosophila wing discs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077177 ◽

1983 ◽

Vol 41 ◽

pp. 720-721

Author(s):

J.S. Ryerse

Keyword(s):

Gap Junctions ◽

Growth Control ◽

Intercellular Junctions ◽

Wing Disc ◽

En Bloc ◽

Metabolic Cooperation ◽

Drosophila Wing ◽

Adult Wing ◽

Wing Discs ◽

Wing Pouch

Gap junctions are intercellular junctions found in both vertebrates and invertebrates through which ions and small molecules can pass. Their distribution in tissues could be of critical importance for ionic coupling or metabolic cooperation between cells or for regulating the intracellular movement of growth control and pattern formation factors. Studies of the distribution of gap junctions in mutants which develop abnormally may shed light upon their role in normal development. I report here the distribution of gap junctions in the wing pouch of 3 Drosophila wing disc mutants, vg (vestigial) a cell death mutant, 1(2)gd (lethal giant disc) a pattern abnormality mutant and 1(2)gl (lethal giant larva) a neoplastic mutant and compare these with wildtype wing discs.The wing pouch (the anlagen of the adult wing blade) of a wild-type wing disc is shown in Fig. 1 and consists of columnar cells (Fig. 5) joined by gap junctions (Fig. 6). 14000x EMs of conventionally processed, UA en bloc stained, longitudinally sectioned wing pouches were enlarged to 45000x with a projector and tracings were made on which the lateral plasma membrane (LPM) and gap junctions were marked.

Download Full-text