Contrasting strategies for tree species to cope with heat and dry conditions at urban sites

Street trees planted at tree pits with impermeable pavements are exposed to a high level of both, atmospheric and edaphic stress. For many species tree physiology, optimal growth, and consequently long-term vitality may be hampered under these harsh conditions. Therefore, maintaining the vitality and promoting the ecosystem services provided by urban trees, for example aesthetic values and microclimatic benefits, it is important to establish trees with a high tolerance to stressful urban environments. Measurements of leaf gas exchange, leaf water potential, leaf surface temperature and chlorophyll-fluorescence were used for identification of specific response of Corylus corluna L., Ginkgo biloba L., Liriodendron tulipifera L., and Tilia cordata Mill. ‘Greenspire’. The summer months in 2013 with a period of heat and drought over eight weeks only interrupted by two rainy days were appropriate to access tree’s strategies to cope with low water availability. During the measurement period, the influence of high temperatures, high values of vapor pressure deficit (VPD) and low soil water availability on stomatal conductance, water-use efficiency (WUE) and leaf water potential (Ψmin, Ψmax ) was highest for Liriodendron followed by Ginkgo. These species showed high reductions in WUE in case of higher air temperatures and high values of VPD. Results indicate an avoidance strategy under increasing heat and VPD. In contrast, Corylus and Tilia followed a tolerance strategy indicated by decreasing values of Ψmin and lower reductions of WUE. In conclusion, wide species-specific variation in response to high temperatures and high VPD indicates that substantial potential exists in the selection for dry and hot urban places.     

Using Epidemiological Studies to Check the Consistency of the Cancer Risks Predicted by High-Dose Animal Experiments: A Methodological Review

Epidemiological studies have been cited in the literature as evidence both for and against the human cancer risks predicted by high-exposure rodent studies. However, there has been little overall consistency in the ways that these animal-to-human comparisons have been made. This review examines some examples of these types of comparisons and describes the methods and techniques used by different investigators. Eleven "key decision areas" that need to be addressed are identified and recommendations for consistent, logical, and statistically appropriate approaches that might be taken to standardize the process are provided. In general, it is suggested that investigators provide the most useful information when they use logical, transparent, and statistically valid comparisons to pursue limited and focused objectives, such as directly testing the validity of an existing regulatory guidance value. Other recommendations include selecting biologically plausible extrapolative models that fit the data and drawing conclusions that are consistent with the study results and objectives.     

The Ranges of Limiting Values of Some Partial Correlations under Conditional Independence

Pearson's partial correlation, Kendall's partial tau, and a partial correlation based on Spearman's rho need not be consistent estimators of zero under conditional independence. The ranges of possible limiting values of these correlations are computed under multivariate normality and lognormality. Students should exercise caution when interpreting these partial correlations as a measure of conditional independence.     

Between the military government and the minority affairs ministry: The construction of the Palestinian minority as a security threat during the first years of the existence of Israel

This study examines correspondence and documents on various matters handled by Israel's Ministry of Minority Affairs during its brief period of operation. The extensive correspondence illuminates aspects relating to the distress faced by Palestinian citizens as a result of the 1948 War and the restrictions imposed on them by the military government, as well as the nature of the emerging relationship between the State and the minority population during the crucial first year following the establishment of Israel. We argue that the construction of the Palestinian minority as a security threat was not a product of the war circumstances, but rather an outcome of interests and political considerations. This construction grew gradually, along with the developing of practices of supervision and means of control, peaking with the subjugation of the Arab population to military government.     

Data-randomized confidence intervals for discrete distributions

In practice non-randomized conservative confidence intervals for the parameter of a discrete distribution are used instead of the randomized uniformly most accurate intervals. We suggest in this paper that a part of the data be used as the random mechanism to create “data-randomized” confidence intervals. A thoughtful utilization of the data leads to intervals that are shorter than the usual conservative intervals but avoids the arbitrariness of the randomized uniformly most accurate intervals. Examples are given using the binomial, Poisson, and extended hypergeometric distributions, as well as applications to a metched case-control study and a randomized clinical trial.     

New directions for management accounting

Using a general systems rationale, this paper develops a theoretical structure for approaching the problem of management accounting. The management control problem is explicated in terms of maintaining a relationship between the enterprise's structure and its environment. An enterprise's structure is composed of three elements (and their inter-relations): a decision and control subsystem; a financial funds subsystem and an operating (physical transforms) subsystem. Portrayed in these terms, the problem of management accounting is shown to require a methodology which is able to take cognizance of economic, sociological, psychological and other aspects of the enterprise system. The model described here provides a general intellectual frame of reference for ordering the problem.