Aantastingen door hout- en bastkevers bij jonge eiken : Literatuuronderzoek en inventarisatie op bedrijven en openbaar groen

In een aantal laanboomsoorten ondervindt de boomkwekerijsector in toenemende mate problemen met stamschade door hout- en bastboorders. Vooral het geslacht Quercus wordt in dit verband vaak genoemd. Bomen met duidelijke symptomen (gaatjes) zijn grotendeels onverkoopbaar en dit leidt dus tot aanzienlijke financiële schade in de laanboomsector. Mogelijke oplossingen (insectenvallen, bestrijdingsprotocollen, preventietechnieken) zijn niet of beperkt ontwikkeld

A review of the dodo and its ecosystem: insights from a vertebrate concentration Lagerstätte in Mauritius

The dodo Raphus cucullatus Linnaeus, an extinct and flightless, giant pigeon endemic to Mauritius, has fascinated people since its discovery, yet has remained surprisingly poorly known. Until the mid-19th century, almost all that was known about the dodo was based on illustrations and written accounts by 17th century mariners, often of questionable accuracy. Furthermore, only a few fragmentary remains of dodos collected prior to the bird's extinction exist. Our understanding of the dodo's anatomy was substantially enhanced by the discovery in 1865 of subfossil bones in a marsh called the Mare aux Songes, situated in southeastern Mauritius. However, no contextual information was recorded during early excavation efforts, and the majority of excavated material comprised larger dodo bones, almost all of which were unassociated. Here we present a modern interdisciplinary analysis of the Mare aux Songes, a 4200-year-old multitaxic vertebrate concentration Lagerstätte. Our analysis of the deposits at this site provides the first detailed overview of the ecosystem inhabited by the dodo. The interplay of climatic and geological conditions led to the exceptional preservation of the animal and associated plant remains at the Mare aux Songes and provides a window into the past ecosystem of Mauritius. This interdisciplinary research approach provides an ecological framework for the dodo, complementing insights on its anatomy derived from the only associated dodo skeletons known, both of which were collected by Etienne Thirioux and are the primary subject of this memoir.publishedVersio

Aantastingen door hout- en bastkevers bij jonge eiken : Literatuuronderzoek en inventarisatie op bedrijven en openbaar groen

In een aantal laanboomsoorten ondervindt de boomkwekerijsector in toenemende mate problemen met stamschade door hout- en bastboorders. Vooral het geslacht Quercus wordt in dit verband vaak genoemd. Bomen met duidelijke symptomen (gaatjes) zijn grotendeels onverkoopbaar en dit leidt dus tot aanzienlijke financiële schade in de laanboomsector. Mogelijke oplossingen (insectenvallen, bestrijdingsprotocollen, preventietechnieken) zijn niet of beperkt ontwikkeld

Combining histology, stable isotope analysis and ZooMS collagen fingerprinting to investigate the taphonomic history and dietary behaviour of extinct giant tortoises from the Mare aux Songes deposit on Mauritius

Taphonomic research of bones can provide additional insight into a site's formation and development, the burial environment and ongoing post-mortem processes. A total of 30 tortoise (Cylindraspis) femur bone samples from the Mare aux Songes site (Mauritius) were studied histologically, assessing parameters such as presence and type of microbial alteration, inclusions, staining/infiltrations, the degree of microcracking and birefringence. The absence of microbial attack in the 4200 year old Mare aux Songes bones suggests the animals rapidly entered the soil whole-bodied and were sealed anoxically, although they suffered from biological and chemical degradation (i.e. pyrite formation/oxidation, mineral dissolution and staining) related to changes in the site's hydrology. Additionally, carbon and nitrogen stable isotopes were analysed to obtain information on the animals' feeding behaviour. The results show narrowly distributed δ13C ratios, indicating a terrestrial C3 plant-based diet, combined with a wide range in δ15N ratios. This is most likely related to the tortoises' drought-adaptive ability to change their metabolic processes, which can affect the δ15N ratios. Furthermore, ZooMS collagen fingerprinting analysis successfully identified two tortoise species (C. triserrata and C. inepta) in the bone assemblage, which, when combined with stable isotope data, revealed significantly different δ15N ratios between the two tortoise species. As climatic changes around this period resulted in increased aridity in the Mascarene Islands, this could explain the extremely elevated δ15N ratio in our dataset. The endemic fauna was able to endure the climatic changes 4200 years ago, although human arrival in the 17th century changed the original habitat to such an extent that it resulted in the extinction of several species. Fortunately we are still able to study these extinct tortoises due to the beneficial conditions of their burial environment, resulting in excellent bone preservation

The Influence of CT Reconstruction Methods on the Accuracy of Monitoring Lung Nodule Diameters at Different Dose Levels

Purpose: This study aims to investigate the effect of filtered back projection (FBP) and sinogram-affirmed iterative reconstruction (SAFIRE) on the accuracy of lung nodule diameter measurements at different dose levels. Method: 48 CT images were acquired (at tube-current time product of 10, 20, 30 and 40 mAs) using an anthropomorphic phantom Lungman N1 ©, containing simulated spherical lung nodules of +100 Hounsfield Units of 5, 8 and 12mm diameter. Images were reconstructed with FBP and SAFIRE strengths 1, 3, and 5. Twelve participants, with radiographic experience, performed nodule diameter measurements for all images. Nodule edge sharpness was calculated for all images by measuring the angle of profile edge slope.Contrast to Noise Ratio (CNR) values were obtained from pixel values in regions of interest (ROIs) in the lung nodule and background air. Measurement accuracy was assessed by calculating the absolute error percentage (AEP) between participant’s measurements and actual nodule size.Results: There is no significant difference in nodule diameter measurement between mAs values and reconstruction algorithms (p-value 0,009 - 0,969). AEP showed no significant difference (p-value 0,041-0,969) for any of the reconstruction algorithms. Discussion: Previous research using SAFIRE suggests a decrease of mAs while maintaining image quality. Furthermore, SAFIRE has the ability to increase CNR and decrease image artefacts. However, the findings in this study suggest that accuracy of lung nodule measurement does not improve with an increase of CNR values nor the line profiles of edge sharpness. Conclusion: Our study suggests that image dose levels can be reduced without compromising nodule diameter measurement accuracy, regardless of reconstruction method

Thin Film Interface Fracture Properties at Scales Relevant to Microelectronics

Mechanical Maritime and Materials Engineerin

Reply to “Marine abundance and its prehistoric past in the Baltic”

In response to the comment by Hausmann et al.1 we highlight here that a number of the key criticisms of Lewis et al.2 are either misinterpretations of our paper or are speculative, requiring rigorous testing via empirical data (and subsequently are topics for further research). We would, therefore, like to take the opportunity to clarify these points, so that others do not misinterpret our study2 in the same way. Hausmann et al.1 provide no physical evidence or data that rebuke our hypothesis, and therefore in the spirit of critical scientific discussion and endeavour, we challenge them (or others) to disprove our hypothesis through high-quality data, and hope that our original paper2 and this further discussion stimulate such work. The criticisms expressed by Hausmann et al. largely focus on the use of a summed probability distribution 14C curve based on oysters as a proxy for shell midden abundance, yet this is only a supportive dataset within the broader theme of this study, and we certainly welcome future research into improving how we quantify shell midden abundance and marine resource intensification in past cultures and societies. However, we highlight that the criticisms of this 14C oyster-derived dataset by Hausmann et al.1 does not detract from the key point of this study, that population increased during periods of increased marine productivity (demonstrated by sediment pigment and other proxy data) and hence increased marine resource availability, when humans predominately consumed a marine-based diet3. Below we respond to the specific points raised by Hausmann et al.1. </p