scholarly journals Conservation and restoration of some icons from the collection of church objects of Agapia Monastery, Neamţ, Romania

2021 ◽  
Author(s):  
Mina Adriana Mosneagu ◽  

Agapia Monastery – the remarkable Moldavian monastery painted by Nicolae Grigorescu – has a precious heritage of icons, books and documents, liturgical textiles, goldsmithing. Among these, the main place is occupied by the icons painted in the XV-XIX centuries, either in post-Byzantine style, in tempera technique, or in realistic style, in oil technique. Some icons from the XVIII-XIX centuries have been preserved and restored in the Icon Restoration laboratory of the Faculty of Theology in Iaşi. In time, the icons kept in the storage of the Monastery Museum have suffered of degradation caused both by the deficient author’s technique and by the exogenous, biotic and abiotic factors. The wooden supports of some icons were severely degraded by the attack of xylophagous insects, being affected both the mechanical resistance and the appearance of the wood. The numerous galleries immediately below the pictorial layer determined its deformation. The pictorial layer of some icons was degraded mainly due to the errors of the painters’ work technique: very thin and fragile preparation layer or excessive binder, which led to the formation of accentuated early cracks. The appearance of the icons was affected either by the chromatic alteration of the protective varnish, or by the deposits of dust and soot in the atmosphere. The interventions for the conservation of the icons consisted in biociding the painting support and in consolidating the pictorial layer detached from the wooden support. The restoration of the icons aimed at removing the dirt deposits from the painting by physico-chemical means, filling the gaps in the icons and their chromatic integration, with easily reversible materials. After conservation and restoration, the icons returned to the Agapia Monastery for use.

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Omri Nahor ◽  
Cristina F. Morales-Reyes ◽  
Gianmaria Califano ◽  
Thomas Wichard ◽  
Alexander Golberg ◽  
...  

Abstract Controlling the life cycle of the green macroalga Ulva (Chlorophyta) is essential to maintain its efficient aquaculture. A fundamental shift in cultivation occurs by transforming the thallus cells into gametangia and sporangia (sporulation), with the subsequent release of gametes and zoids. Sporulation occurrence depends on algal age and abiotic stimuli and is controlled by sporulation inhibitors. Thus, quantification of sporulation intensity is critical for identifying the biotic and abiotic factors that influence the transition to reproductive growth. Here, we propose to determine the sporulation index by measuring the number of released gametes using flow cytometry, in proportion to the total number of thallus cells present before the occurrence of the sporulation event. The flow cytometric measurements were validated by manually counting the number of released gametes. We observed a variation in the autofluorescence levels of the gametes which were released from the gametangia. High autofluorescence level correlated to phototactically active behaviour of the gametes. As autofluorescence levels varied between different groups of gametes related to their mobility, flow cytometry can also determine the physiological status of the gametes used as feedstock in seaweed cultivation.


2001 ◽  
Vol 22 (1) ◽  
pp. 21-32 ◽  
Author(s):  
Sylvie Thurnheer ◽  
Heinz-Ulrich Reyer

AbstractPredictions about population and community dynamics are usually based on lab experiments. Because the results are difficult to transfer to natural conditions, the major purpose of this study was to test the effects of biotic and abiotic factors on tadpole populations in a natural environment. We stocked six ponds, created the previous year, with known numbers of Rana esculenta and R. lessonae tadpoles and followed their development over several months. When compared among ponds, tadpole density correlated positively with the nitrate:phosphate ratio. This suggests that water chemistry may have affected survival, either directly or indirectly via productivity. Within ponds, both species showed a clear preference for the shallow zone. This behavior probably reflects a preference for warm water close to the surface, rather than avoidance of predators, because relative densities of odonates also increased from deep to shallow zones. This study is one of few that not only considers the distribution of the anuran tadpoles but the distribution of their predators as well.


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