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C2 photosynthesis is a photosynthetic pathway in which photorespiratory CO2 release and refixation are enhanced in leaf bundle sheath (BS) tissues. The evolution of C2 photosynthesis has been hypothesized to be a major step in the origin of C4 photosynthesis, highlighting the importance of studying C2 evolution. In this study, physiological, anatomical, ultrastructural, and immunohistochemical properties of leaf photosynthetic tissues were investigated in six non‐C4Tribulus species and four C4Tribulus species. At 42°C, T. cristatus exhibited a photosynthetic CO2 compensation point in the absence of respiration (C*) of 21 µmol mol−1, below the C3 mean C* of 73 µmol mol−1. Tribulus astrocarpus had a C* value at 42°C of 55 µmol mol−1, intermediate between the C3 species and the C2T. cristatus. Glycine decarboxylase (GDC) allocation to BS tissues was associated with lower C*. Tribulus cristatus and T. astrocarpus allocated 86% and 30% of their GDC to the BS tissues, respectively, well above the C3 mean of 11%. Tribulus astrocarpus thus exhibits a weaker C2 (termed sub‐C2) phenotype. Increased allocation of mitochondria to the BS and decreased length‐to‐width ratios of BS cells, were present in non‐C4 species, indicating a potential role in C2 and C4 evolution. Summary statement: Physiological, structural, and immunohistochemical analyses of leaf tissues indicate sub‐C2 and C2 character states occurring in Tribulus (Zygophyllaceae). These data reveal novel insights into the mechanisms by which photorespiratory CO2 refixation facilitates the evolution of C4 photosynthesis. [ABSTRACT FROM AUTHOR]

Site layout planning can affect productivity and is crucial to project success. However, as construction is heterogeneous in the nature of its organizations, project designs, time constraints, environmental effects, etc., site layout planning for each project becomes unique. Affected by many uncertainties (variables) and variations, site layout planning is a typical multiobjective problem. To facilitate the decision-making process for these problems, a nonstructural fuzzy decision support system (NSFDSS) is proposed. NSFDSS integrates both experts' judgment and computer decision modeling, making it suitable for the appraisal of complicated construction problems. The system allows assessments based on pairwise comparisons of alternatives using semantic operators that can provide a reliable assessment result even under the condition of insufficient precise information. DOI: 10.1061/(ASCE)0733-9364(2002)128:3(220) CE Database keywords: Decision support systems; Fuzzy sets; Site preparation, construction.

Accuracy in estimating activity duration is one of the key prerequisites for successful construction planning. Efficient material transportation plays an important role in reducing costs and time. Time measurement and work-study techniques can provide good estimation of activity duration, but forming the databank for various conditions is expensive. The use of empirical models has been developed as an alternative to overcome the deficiency while maintaining a reasonable accuracy. In this research traditional linear regression models and nonlinear neural network models have been developed for predicting hoisting times of a tower crane. It is found that nonlinear neural network models can achieve higher accuracy. However, planners may find that the regression models, which describe the relationship between the variables in more simplistic terms, could allow them to shorten the hoisting times by manipulating the input variables. The results and the merits of the models are discussed. DOI: 10.1061/(ASCE)0887-3801(2002)16:1(76) CE Database keywords: Neural networks; Cranes; Time studies; Construction management; Multiple regression models; Nonlinear analysis.

Accurate assessment of hoisting times is crucial for planning construction activities. The objective of this paper is to develop reasonably accurate prediction models to assess hoisting times of tower cranes. Twenty variables considered attributable to the hoisting time are evaluated. In modeling the hoisting movements, the upward hoisting and downward hoisting of a hoisting cycle are classified as the supply hoisting and the return hoisting. Multiple regression techniques are used for analyzing and building up the models. The hoisting of precast concrete facades and concrete skips are studied. The significance of the variables are discussed and compared. Finally, the paper presents an example of applying the models.

Will climate change lead to invasive species evolving faster than native or naturalized species? Gianoli and Molina‐Montenegro showed that, under warming and drought, the evolution of photosynthetic capacity does not always favor invasive species. These data raise interesting questions for the study of evolution of invasive species under climate change. [ABSTRACT FROM AUTHOR]

Will climate change lead to invasive species evolving faster than native or naturalized species? Gianoli and Molina‐Montenegro showed that, under warming and drought, the evolution of photosynthetic capacity does not always favor invasive species. These data raise interesting questions for the study of evolution of invasive species under climate change. [ABSTRACT FROM AUTHOR]

This article examines the relationship between biographical characteristics of top executives and the level of corporate environmental information disclosure (EID) for Chinese-listed companies based on the upper echelons theory. Some interesting findings appear. Using a sample of 871 manufacturing companies having data of EID, we find that under the current situations such as the lack of external pressures on environmental protection, especially from the government, top executives may have the same attitude toward EID, focusing companies on economic goals rather than taking environmental responsibility seriously. This suggests that strengthening environmental supervision and stricter and more specific environmental controls for disclosure are in urgent need in China. [ABSTRACT FROM PUBLISHER]

Planning is a major determinant of project success in the construction industry. There are many planning techniques, each with its strengths and weaknesses. However, the accuracy of determining the activity duration is the prime requisite for effective planning tools. High-rise building construction prevails in the building industry of Hong Kong. Hence, tower cranes are used extensively on building sites and are particularly useful in vertical and horizontal transportation in one single process. However, the number of tower cranes allowed on a site is restricted by site area and location, including closeness to adjacent properties or to buildings under construction. In a densely populated urban area like Hong Kong, the required number of tower cranes may not be permissible. Therefore planners have to overcome this problem by formulating a balanced crane usage schedule or crane allocation schedule to avoid conflicts between users. However, imbalance in crane usage is so common on site that the estimation of hoisting time may not be realistic. Therefore the prediction of hoisting time is worthy of study and is critical in formulating a realistic crane schedule.

C 2 photosynthesis is a photosynthetic pathway in which photorespiratory CO 2 release and refixation are enhanced in leaf bundle sheath (BS) tissues. The evolution of C 2 photosynthesis has been hypothesized to be a major step in the origin of C 4 photosynthesis, highlighting the importance of studying C 2 evolution. In this study, physiological, anatomical, ultrastructural, and immunohistochemical properties of leaf photosynthetic tissues were investigated in six non-C 4 Tribulus species and four C 4 Tribulus species. At 42°C, T. cristatus exhibited a photosynthetic CO 2 compensation point in the absence of respiration (C * ) of 21 µmol mol -1 , below the C 3 mean C * of 73 µmol mol -1 . Tribulus astrocarpus had a C * value at 42°C of 55 µmol mol -1 , intermediate between the C 3 species and the C 2 T. cristatus. Glycine decarboxylase (GDC) allocation to BS tissues was associated with lower C * . Tribulus cristatus and T. astrocarpus allocated 86% and 30% of their GDC to the BS tissues, respectively, well above the C 3 mean of 11%. Tribulus astrocarpus thus exhibits a weaker C 2 (termed sub-C 2 ) phenotype. Increased allocation of mitochondria to the BS and decreased length-to-width ratios of BS cells, were present in non-C 4 species, indicating a potential role in C 2 and C 4 evolution., (© 2024 The Author(s). Plant, Cell & Environment published by John Wiley & Sons Ltd.)