Abstract. Endolithic microhabitats have been described as the last
refuge for life in arid and hyper-arid deserts where life has to deal with
harsh environmental conditions. A number of rock substrates from the
hyper-arid Atacama Desert, colonized by endolithic microbial communities
such as halite, gypsum crusts, gypcrete, calcite, granite and ignimbrite,
have been characterized and compared using different approaches. In this
work, three different endolithic microhabitats are described, each one with
a particular origin and architecture, found within a lithic substrate known
as gypcrete. Gypcrete, an evaporitic rock mainly composed of gypsum
(CaSO4 ⋅ 2H2O) and collected in the Cordón de Lila
area of the desert (Preandean Atacama Desert), was found to harbour
cryptoendolithic (within pore spaces in the rock), chasmoendolithic (within
cracks and fissures) and hypoendolithic (within microcave-like pores in the
bottom layer of rock) microhabitats. A combination of microscopy investigation
and high-throughput sequencing approaches were used to characterize the
endolithic communities and their habitats at the microscale within the same
piece of gypcrete. Microscopy techniques revealed differences in the
architecture of the endolithic microhabitats and the distribution of the
microorganisms within those microhabitats. Cyanobacteria and Proteobacteria
were dominant in the endolithic communities, of which the hypoendolithic
community was the least diverse and hosted unique taxa, as a result of less
access to sun radiation. These results show, for the first time, that the
differences in the architecture of a microhabitat, even within the same
piece of a lithic substrate, play an essential role in shaping the
diversity and composition of endolithic microbial communities.
The paper presents the automated on-line system for wood logs 3D geometry scanning. The system consists of 6 laser triangulation scanners and is able to scan full wood logs which can have the diameter ranging from 250 mm to 500 mm and the length up to 4000 mm. The system was developed as a part of the BIOSTRATEG project aiming to optimize the cutting of logs in the process of wood planks manufacturing by intelligent positioning in sawmill operation. This paper illustrates the detailed description of scanner construction, full measurement process, system calibration and data processing schemes. The full 3D surface geometry of products and their applied portion of selected wood logs formed after cutting out the cant is also demonstrated.
Comparison studies of different measurement methods using a Coordinate Measuring Arm are presented. Studies were divided into two parts. The first was point measurements of contact and pseudo-scanning contact measurements. The second part consisted of point measurements of contact and non-contact scanning measurements. Contact research (point measurements and the pseudo-scanning) were accomplished with the use of PowerINSPECT software, whereas non-contact with use of Focus Handheld and Focus Inspection software. Handheld Focus was used to collect a point cloud and its processing, while the detection of set elements was made using the second software from the group of Focus. According to the developed procedure for both parts sample elements with known nominal values were measured (available CAD model of object of research). It became the basis for examining whether there are statistically significant differences between results of different methods in both parts. Statistical comparison of measurement methods was carried out using four tests: Comparison of Means, Comparison of Standard Deviations, Comparison of Medians and a Kolmogorov-Smirnov Test.
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