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Artificial intelligence (AI) solutions that automatically extract information from digital histology images have shown great promise for improving pathological diagnosis. Prior to routine use, it is important to evaluate their predictive performance and obtain regulatory approval. This assessment requires appropriate test datasets. However, compiling such datasets is challenging and specific recommendations are missing. A committee of various stakeholders, including commercial AI developers, pathologists, and researchers, discussed key aspects and conducted extensive literature reviews on test datasets in pathology. Here, we summarize the results and derive general recommendations for the collection of test datasets. We address several questions: Which and how many images are needed? How to deal with low-prevalence subsets? How can potential bias be detected? How should datasets be reported? What are the regulatory requirements in different countries? The recommendations are intended to help AI developers demonstrate the utility of their products and to help regulatory agencies and end users verify reported performance measures. Further research is needed to formulate criteria for sufficiently representative test datasets so that AI solutions can operate with less user intervention and better support diagnostic workflows in the future.

Funder: Sime Darby Foundation, Funder: Sir Philip Reckitt Educational Trust, Funder: Czech Science Foundation; Id: http://dx.doi.org/10.13039/501100001824, Logging and habitat conversion create hotter microclimates in tropical forest landscapes, representing a powerful form of localised anthropogenic climate change. It is widely believed that these emergent conditions are responsible for driving changes in communities of organisms found in modified tropical forests, although the empirical evidence base for this is lacking. Here we investigated how interactions between the physiological traits of genera and the environmental temperatures they experience lead to functional and compositional changes in communities of ants, a key organism in tropical forest ecosystems. We found that the abundance and activity of ant genera along a gradient of forest disturbance in Sabah, Malaysian Borneo, was defined by an interaction between their thermal tolerance (CTmax) and environmental temperature. In more disturbed, warmer habitats, genera with high CTmax had increased relative abundance and functional activity, and those with low CTmax had decreased relative abundance and functional activity. This interaction determined abundance changes between primary and logged forest that differed in daily maximum temperature by a modest 1.1°C, and strengthened as the change in microclimate increased with disturbance. Between habitats that differed by 5.6°C (primary forest to oil palm) and 4.5°C (logged forest to oil palm), a 1°C difference in CTmax among genera led to a 23% and 16% change in relative abundance, and a 22% and 17% difference in functional activity. CTmax was negatively correlated with body size and trophic position, with ants becoming significantly smaller and less predatory as microclimate temperatures increased. Our results provide evidence to support the widely held, but never directly tested, assumption that physiological tolerances underpin the influence of disturbance‐induced microclimate change on the abundance and function of invertebrates in tropical landscapes. A free Plain Language Summary can be found within the Supporting Information of this article.

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The Tea Bag Index (TBI) is a standardised and cheap method to quantify microbial-driven decomposition by measuring the mass loss of tea within tea bags. Termites are known to damage the bags to access the content, rendering the method less suitable for termite-rich ecosystems. Extension of the TBI to accommodate and incorporate the influence of termites would broaden its applicability to include termite-rich ecosystems, such as tropical forests. We extended the original TBI by applying physical and chemical termite-exclusion methods. Tea mass loss and the proportion of tea bags detected by termites in the original TBI were also recorded to infer the role of termites in litter decomposition. TBI estimates derived from the original and extended TBI were compared, benchmarked against global estimates, and validated with time-series mass loss data. Using the original TBI, we found that termites damaged up to 80 % of tea bags and consumed the recalcitrant fraction of tea in several of them, leaving only 20 % of tea bags from which TBI estimates could be retrieved. The physical termite-exclusion treatment completely eliminated termite-infringement, thus preserving the full sample size for estimating TBI parameters. The chemical termite-exclusion treatment also successfully excluded termites, but potentially inhibited microbial decomposition and made TBI estimates unreliable. In the absence of termite-infringement, both the TBI estimates and time-series analysis revealed a low decomposition rate compared to other measurements in tropical and temperate regions. We propose an extended TBI, in which the physical termite-exclusion treatment is used to preserve the retrieval rate of TBI parameters and reliably measure microbial-driven decomposition, while the original TBI is used to incorporate the contribution of termites in driving litter mass loss. By characterising both termite- and microbial-driven decomposition, the extended TBI will provide a comprehensive understanding of decomposition and its drivers in termite-rich ecosystems, and permit global comparisons.

A - C absolute weight-increase in g and D - F weight-increase relative to dryweight for beam geometry; humidification (relative humidity in air) and moistening (water dipping) of Po. alba, P. radiata and E. regnans over time. Average values are marked by a solid thick line. Period I describes the process of saturation at 80% RH (28 ºC), period II is the increase in weight owing to the wood being dipped in water and in period III the wood is oven-dried again

Animals use cues to find their food, in microhabitats within their physiological tolerances. Termites build and modify their microhabitat, to transform hostile environments into benign ones, which raises questions about the relative importance of cues. Termites are desiccation intolerant and foraging termites are attracted to water, so most research has considered moisture to be a cue. However, termites can also transport water to food, and so moisture may play other roles than previously considered. To examine the role of moisture, we compared Coptotermes acinaciformis termite foraging decisions in laboratory experiments when they were offered dry and moist wood, with and without load. Without load, termites preferred moist wood and ate it without any building, whereas they moistened dry wood after wrapping it in a layer of clay. For the ‘With load’ units, termites substituted some of the wood for load-bearing clay walls, and kept the wood drier than on the unloaded units. As drier wood has higher compressive strength and higher rigidity, it allows more of the wood to be consumed. These results suggest that moisture plays a more important role in termite ecology than previously thought. Termites manipulate the moisture content according to the situational context and use it for multiple purposes: increased moisture levels soften the fibre, which facilitates foraging, yet keeping the wood dry provides higher structural stability against buckling which is especially important when foraging on wood under load.

The ‘No load’ units showed on average far less clay per volume than the ‘With load’ units. The notches of the boxes indicate 95% confidence intervals which are non-overlapping hence differences between the ‘No load’ and the ‘With load’ units are significant at the 5% level; results here are qualitatively the same as in Oberst, Lai & Evans [10].

Animals use cues to find their food, in microhabitats within their physiological tolerances. Termites build and modify their microhabitat, to transform hostile environments into benign ones, which raises questions about the relative importance of cues. Termites are desiccation intolerant and foraging termites are attracted to water, so most research has considered moisture to be a cue. However, termites can also transport water to food, and so moisture may play other roles than previously considered. To examine the role of moisture, we compared Coptotermes acinaciformis termite foraging decisions in laboratory experiments when they were offered dry and moist wood, with and without load. Without load, termites preferred moist wood and ate it without any building, whereas they moistened dry wood after wrapping it in a layer of clay. For the ‘With load’ units, termites substituted some of the wood for load-bearing clay walls, and kept the wood drier than on the unloaded units. As drier wood has higher compressive strength and higher rigidity, it allows more of the wood to be consumed. These results suggest that moisture plays a more important role in termite ecology than previously thought. Termites manipulate the moisture content according to the situational context and use it for multiple purposes: increased moisture levels soften the fibre, which facilitates foraging, yet keeping the wood dry provides higher structural stability against buckling which is especially important when foraging on wood under load.

(a), wood block after 2 days; clay layer is scraped off; (b), wooden block after 6 days: the arrows indicate nibbling activity (grazing) of the termites; (c) after about 18 days the termites removed significant amounts of wood, leaving trenches at all sides (d) as well as starting to eat along the grain (e); (f), after 22 days the wood was reduced already significantly jointing the trenches and holes.

Quasi-static compression test, A, experimental setup, B, close-up of sample after the point of yielding strength being crushed with clearly visible slip plane.

Mudding and foraging related weight changes. Weight change over time for three different kinds of wood using 20x20mm2 and 30mm length. Thin grey lines indicate failed experiments (rot fungus, no/little contact). Thick lines highlight successful experiments; peak values are marked as thick dots while μ and σ mark their standard deviation.

Setup of pressure trial with wood of different tree species under compression using 5×5mm2 cross section. (a), Schematic diagram, (b), top view of one setup and (c), side view of the same setup loaded with water drums

Termite mounds built by representatives of the family Termitidae are among the most spectacular constructions in the animal kingdom, reaching 6–8 m in height and housing millions of individuals. Although functional aspects of these structures are well studied, their evolutionary origins remain poorly understood. Australian representatives of the termitid subfamily Nasutitermitinae display a wide variety of nesting habits, making them an ideal group for investigating the evolution of mound building. Because they feed on a variety of substrates, they also provide an opportunity to illuminate the evolution of termite diets. Here, we investigate the evolution of termitid mound building and diet, through a comprehensive molecular phylogenetic analysis of Australian Nasutitermitinae. Molecular dating analysis indicates that the subfamily has colonized Australia on three occasions over the last approximately 20 Myr. Ancestral-state reconstruction showed that mound building arose on multiple occasions and from diverse ancestral nesting habits, including arboreal and wood or soil nesting. Grass feeding appears to have evolved from wood feeding via ancestors that fed on both wood and leaf litter. Our results underscore the adaptability of termites to ancient environmental change, and provide novel examples of parallel evolution of extended phenotypes.

Termite mounds built by representatives of the family Termitidae are among the most spectacular constructions in the animal kingdom, reaching 6–8 m in height and housing millions of individuals. Although functional aspects of these structures are well studied, their evolutionary origins remain poorly understood. Australian representatives of the termitid subfamily Nasutitermitinae display a wide variety of nesting habits, making them an ideal group for investigating the evolution of mound building. Because they feed on a variety of substrates, they also provide an opportunity to illuminate the evolution of termite diets. Here, we investigate the evolution of termitid mound building and diet, through a comprehensive molecular phylogenetic analysis of Australian Nasutitermitinae. Molecular dating analysis indicates that the subfamily has colonized Australia on three occasions over the last approximately 20 Myr. Ancestral-state reconstruction showed that mound building arose on multiple occasions and from diverse ancestral nesting habits, including arboreal and wood or soil nesting. Grass feeding appears to have evolved from wood feeding via ancestors that fed on both wood and leaf litter. Our results underscore the adaptability of termites to ancient environmental change, and provide novel examples of parallel evolution of extended phenotypes.

This dissertation is divided into three freestanding chapters. Chapter I describes the total synthesis of the cytotoxic marine natural product trans-2,5-bis(6'-bromo-3'­ indolyl)piperazine (1), as well as racemic cis-2,5-bis(6'-bromo-3'-indolyl)piperazine (78). Also described are the syntheses of two additional analogs of the natural product 1; trans-2,5-bis(5'-bromo-3'-indolyl)piperazine (79) and racemic cis-2,5-bis(5'-bromo-3'­ indolyl)piperazine (80). These piperazines were prepared by electophillic addition of the indole to cis-3,6-dibromo-1 ,4-bis(tert-butoxycarbonyl)-2,5-piperazinedione, followed by isomerization and reduction of the resulting 3,6-bis(indolyl)-2,5-piperazinediones with borane-tetrahydrofuran. The piperazine products 1 and 78-80 were all found to be cytotoxic. In collaboration with the National Cancer Institute (NCI), in vivo testing was performed. The piperazine compounds 78, 80 and 1 have been identified as selectively cytotoxic to colon tumors. NCI has detetmined that the maximally tolerated doses in mice of 1 and 78 are 400 and 450 mg/kg, respectively. Efforts are underway to provide more of 1, 78 and 80 for further in vivo testing by the NCI. In addition the piperazine products were found to inhibit phorbol-induced inflammation in the Mouse Ear Edema Assay at levels ranging from 44% for 78, 69% for 80 and 71% for 1 to a maximum of 80% for 79. Chapter 2 describes the isolation and stucture elucidation of the marine natural product (2R, 3R, 10R)-(Z)-2-amino-1,3,10-trihydroxy-11-octadecene (81). The stucture was determined by a combination of spectral analyses and derivatizations. The Modified Mosher Method was used to determine the absolute configurations of C-3 and C-l 0. The compound was determined to possess broad spectrum anti-microbial properties, and was also found to inhibit phorbol-induced inflammation in the Mouse Ear Edema Assay at a level of 43%. Chapter 3 describes the isolation and synthesis of a glycine derivative of the cytotoxic marine natural product ilimaquinone. The structure of the new compound, called glycinylilimaquinone (91) was determined by spectral methods and by partial synthesis. Compound 91 was also found to be cytotoxic (eg. HCT-116, IC50 = 7.8)µg/mL) and evaluated against the P388 murine lukemia model in vivo, but at a maximally tolerated dose showed no anti-tumor activity. Also described are stucture-activity relationships for some ilimaquinone analogs tested for Golgi vessiculation and microtubule depolymerization in rat kidney cells.

The first International Peat Congress (IPC) held in the tropics - in Kuching (Malaysia) - brought together over 1000 international peatland scientists and industrial partners from across the world ("International Peat Congress with over 1000 participants!," 2016). The congress covered all aspects of peatland ecosystems and their management, with a strong focus on the environmental, societal and economic challenges associated with contemporary large-scale agricultural conversion of tropical peat.

As eusocial and wood-dwelling insects, termites have been shown to use vibrations to assess their food, to eavesdrop on competitors and predators and to warn nest-mates. Bioassay choice experiments used to determine food preferences in animals often consider single factors only but foraging decisions can be influenced by multiple factors such as the quantity and quality of the food and the wood as a medium for communication. A statistical analysis framework is developed here to design a single bioassay experiment to study multifactorial foraging choice (Pinus radiata) in the basal Australian termite species Coptotermes (C.) acinaciformis (Isoptera: Rhinotermitidae). By employing a correlation analysis, 17 measured physical properties of 1417 Pinus radiata veneer discs were reduced to five key material properties: density, moisture absorption, early wood content, first resonance frequency and damping. By applying a fuzzy c-means clustering technique, these veneer discs were optimally paired for treatment and control trials to study food preference by termites based on these five key material properties. A multifactorial analysis of variance was compared to a permutation analysis of the results indicating for the first time that C. acinaciformis takes into account multiple factors when making foraging decisions. C. acinaciformis prefer denser wood with large early wood content, preferably humid and highly damped. Results presented here have practical implications for food choice experiments and for studies concerned with communication in termites as well as their ecology and coevolution with trees as their major food source.