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The worldwide demand for avocados has resulted in the planting of millions of young plants each year. However, global warming, resulting in high temperatures, sensed as heat stress, may severely damage these new plantings. The objective of this study was to assess the risks of heat stress on young avocado plants. We aimed to characterize different physiological parameters of young ‘Hass’ plant leaves following exposure to high temperatures under low light (LL) intensity and to pinpoint the temperature threshold for significant heat stress damage in these plants. To this end, young potted plants were subjected to different temperature gradients in a controlled-climate chamber. Minor and severe leaf damage was apparent in plants subjected to the 51 °C and 53 °C treatments, respectively. Minor and vast reductions in optimal quantum yield efficiency of photosystem II (Fv/Fm) values were observed in plants subjected to 51 °C and 53 °C, respectively. Heat stress treatments significantly reduced CO2 assimilation in plants subjected to 49 °C and higher temperatures. Stomatal conductance to water vapour and substomatal internal CO2 concentration were less sensitive to the heat treatments. These results imply that the heat damage threshold for young avocado plants under LL conditions is between 49 °C and 51 °C, whereas at 53 °C, severe and irreversible leaf damage occurs.

Here we describe preliminary results of a simulation-based study investigating the connection between tumor-treating fields (TTFields) distribution in the brain and glioblastoma patient outcomes. In order to perform this study, we developed a semiautomatic method for creating realistic head models from glioblastoma patient MRI using a deformable template and atlas-based registration. This method, which is described in detail in this chapter, is robust and fast, making it suitable for rapid creation of multiple realistic head models. Using this method, we created 119 head models of newly diagnosed glioblastoma patients that were treated with tumor-treating fields. Finite element simulations were used to simulate delivery of TTFields to these patients, and the connection between field intensity distribution at the tumor bed and patient outcome was analyzed. The result of this analysis support the hypothesis that increasing field intensity at the tumor bed improves patient outcome.

Green roofs provide important ecosystem services in urban areas. In Mediterranean and other semi-arid climate regions, most perennial plants on green roofs need to be irrigated during the dry season. However, the use of freshwater in such regions is scarce. Therefore, the possibility of using grey water should be examined. Coal ash, produced primarily from the burning of coal in power plants, constitutes an environmental contaminant that should be disposed. One option is to use ash as a growing substrate for plants. Here, we compare the effects of irrigating with grey- versus tap-water and using ash versus perlite as growing substrates in green roofs. The study was conducted in northern Israel in a Mediterranean climate. The design was full factorial with three factors: water-type (grey or tap-water)×substrate-type (coal ash vs perlite)×plant species (Phyla nodiflora, Convolvulus mauritanicus or no-plant). The development of plants and the quality of drainage water along the season, as well as quality of the used substrates were monitored. Both plant species developed well under all the experimental conditions with no effect of water type or substrate type. Under all treatments, both plant species enhanced electrical conductivity (EC) and chemical oxygen demand (COD) of the drainage water. In the summer, EC and COD reached levels that are unacceptable in water and are intended to be reused for irrigation. We conclude that irrigating with grey water and using coal ash as a growth substrate can both be implemented in green roofs. The drainage from tap water as well as from grey water can be further used for irrigating the roof, but for that, COD and EC levels must be lowered by adding a sufficient amount of tap water before reusing.

Green roof research is a multidisciplinary and new research area. We conducted a bibliometric quantification to assess the rate of publications in specific areas of research for this novel research area based on the scientific literature as available from the Web of Science. Bibliometric research can provide valuable information about changes in the trends within a particular area of research. For example, we found that the number of publications in this field increased in the last two decades at very similar pace to other pre-established academic disciplines. We also found that papers on green roofs were classified into 32 research areas. There was very little change in the frequency of most research areas through time. The percentages of plant sciences, forestry, marine and freshwater biology and biodiversity conservation of the total research areas classifications used each year increased significantly with time, while architecture decreased significantly with time signifying an increased interest in environmental issues and less focus on architectural issues. The distribution of publications between countries has been skewed, with the USA and the EU conducting 66% of the research, and thus allocation of research effort is focused in those continents and predominantly in temperate ecosystems. However, there has been a sharp increase in the number of countries that conduct green roof research. Our work provides a suite of indicators that can be combined to give a useful picture of the development of green roof research and identifies the challenges which lie ahead for this novel research area.

TTFields is an antimitotic cancer treatment that utilizes low intensity (1-3 V/cm) alternating electric fields in the intermediate frequency (100-300 kHz), approved by the Food and Drug Administration (FDA) for the treatment of Glioblastoma Multiforme (GBM) located in the supratentorial regions of the brain. A clinical trial testing the efficacy of TTFields for treating brain metastases is currently underway (METIS, NCT02831959). TTFields are delivered using two pairs of transducer arrays placed on the patient's skin in the proximity of the tumor. The electric field generated by the arrays is localized to a region located roughly between the arrays. The standard array layouts used to deliver TTFields involve placement of the arrays on the supratentorial regions of the head. With these array layouts,therapeutic field intensities above 1 V/cm are only achieved within the supratentorial brain. Therefore, treatment with TTFields has been limited to tumors located in the supratentorium. Although Tumors located in the infratentorial brain are rare in adult patients, they are common in the pediatric population. In addition, brain metastases commonly occur in the infratentorium. Hence, there is a need to identify array layouts that can effectively deliver TTFields to the infratentorial brain. Here we present computer simulations designed to identify new array layouts that deliver high field intensities to the infratentorial brain. To simulate delivery of TTFields to the brain, we used realistic computerized head models of an adult human female and an adult human male. Virtual transducer arrays were placed on the models, and boundary conditions were set to simulate delivery of TTFields at 200 kHz. Various array layouts were tested, and field distributions resulting from the layouts were evaluated. In both head models, the highest field intensities were delivered to the infratentorial brain by a layout, in which each array of one pair was laterally placed superficially to the lower region of the occipital lobe, and the two arrays of the second pair were placed on the calvarium and the superior aspect of the neck. In both models, the pair of arrays in which one array was placed on the calvarium and one array on the superior aspect of the neck delivered field intensities above 1.1 V/cm to over 95% of the volume of the infratentorial brain, and the pair of arrays placed on the lateral aspects of the occipital lobe delivered field intensities above 1 V/cm to over 95% of the infratentorial brain. Both pairs of arrays delivered field intensities above 1 V/cm to significant portions of the supratentorial brain. This work shows that TTFields at therapeutic intensities can be delivered to the cerebellum, stem and surrounding regions which are located inferior to the tentorium, suggesting that treatment of tumors within these with TTFields is feasible. Citation Format: Shay Levy, Ariel Naveh, Ze'ev Bomzon, Eilon Kirson, Uri Weinberg. Computational studies show that Tumor Treating Fields can be delivered to the infratentorial brain at therapeutic levels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3199.

This article surveys the ethnobotany ofZiziphus spina-christi(L.) Desf. in the Middle East from various aspects: historical, religious, philological, literary, linguistic, as well as pharmacological, among Muslims, Jews, and Christians. It is suggested that this is the only tree species considered "holy" by Muslims (all the individuals of the species are sanctified by religion) in addition to its status as "sacred tree " (particular trees which are venerated due to historical or magical events related to them, regardless of their botanical identity) in the Middle East. It has also a special status as "blessed tree" among the Druze.