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I laboratori CNR-ICVBC-FI e CNR-IAS-GE (ex ISMAR-GE) sono stati coinvolti in una prima proposta di indagini a supporto del restauro in oggetto, nell'ambito delle convenzioni in essere con IRES SpA Costruzioni e Restauro. Alla luce delle evoluzioni del cantiere e delle tempistiche in essere è stato formulato un piano operativo finalizzato ad attività di ricerca e diagnostica a supporto delle operazioni di restauro. Sono state effettuate: - consulenza scientifica per la scelta del sistema protettivo da adottare e sua valutazione in campo - definizione di un numero significativo di aree sui diversi bronzi per caratterizzare la diversità di superfici presenti e il comportamento del trattamento protettivo in funzione della superficie sottostante - caratterizzazione delle proprietà chimico-fisiche nelle aree di test individuate e valutazione dei risultati in funzione della successiva manutenzione. In stretta collaborazione con il responsabile del restauro dei bronzi, sono state selezionate 8 zone (indicativamente di circa 18x10cm) di valutazione e monitoraggio distribuite su 4 diverse statue, dove - attraverso un approccio totalmente non invasivo con strumentazione portatile - è stata eseguita un'approfondita caratterizzazione delle superfici nelle diverse fasi d'avanzamento delle operazioni di restauro. Le zone scelte per le indagini sono state identificate attraverso apposite maschere, riposizionabili nel tempo, che potranno essere utilizzate anche per un eventuale monitoraggio non contemplato nella presente attività. Nello specifico come attività CNR-ICVBC, sono state valutate l'omogeneità di applicazione, la resa estetica, la presenza di prodotti di alterazione residui e/o di neoformazione.

Presentazioni delle analisi preliminari sulla lastra egizia del Museo Nazionale Archeologico di Firenze

Analyses on pigments and plasters from archaeological site of Utica (Tunisia)

Indagini petrografiche ed isotopiche su marmi del museo dell'Opera del Duomo (Firenze)

Fired bricks have been used for construction purposes in China for at least two thousand years. Since the mid-19th century the manufacture of bricks has shifted from an old to a new system. The unique Chinese blue brick has been gradually replaced by the European red brick and other modern products. This study focuses on Shanghai as a representative city in that transitional period, aims at addressing the true condition of the modern changes in China's brick history and the heritage today. The paper presents the first results of an interdisciplinary investigation. Fourteen brick samples and one sample of raw material were studied with regard to the mineralogical, petrographic, chemical, physical, mechanical characteristics, and the maximum firing temperature. It also makes measurements of the presented soluble salts in the altered brick samples. Preliminary conclusions are drawn with regard to three critical issues: the provenance of the bricks, the hitherto undocumented changes in the manufacturing technology, and the condition of the brick material in terms of conservation.

The Cathedral of Santa Maria del Fiore in Florence (XII-XV centuries) plays a fundamental role in the historic architecture of the city; it was decorated by using three stones of the different colour: white marble, red limestones (so-called "red marble") and green serpentine (so-called "green marble"). White and green marbles have been widely studied, whereas not sufficient data are available on the red marbles; different types of this latter have been used as a cladding of the Cathedral, and it is difficult to distinguish them and consequently to obtain information on their provenance. A research carried out at the Archive of the Florence Cathedral, made it possible to know that since the XV century, stones of different provenance were used both for the original decoration and for the following restoration works until today. As a matter of fact, many of these stones come from three geological formations of the Central Apennine: Scaglia Toscana and Rosso Ammonitico (Tuscan Sequence), Scaglia Rossa (Umbrian Sequence). It is easy to differentiate at naked eye the claddings belonging to Rosso Ammonitico showing nodular aspect from those belonging to the groups Scaglia Toscana and Scaglia Rossa which instead show massive appearance. Furthermore, different supply quarries were used for each of the three formations and macroscopically it is not possible to recognize the single quarry of provenance. To this regard the chemical composition and, in particular, the trace element abundances could help in the identification but, due to the architectural and historical importance of the Cathedral, it was not possible to collect samples. Therefore XRF analyses with the portable instrument (model TRACER III SD by Bruker) have been carried out in situ on the red claddings; the traditional XRF technique (model WD-XRF Rigaku Primus II) was, in addition, used to determine the composition of the stones coming from the different quarries sites. The results permitted to obtain a chemical database of the different quarries; these data have been compared with those acquired through the portable X-ray Fluorescence. The comparison permitted to achieve an important result: the different typologies of red marbles can be distinguished through the abundances of some trace elements (e.g. Sr and Ba) which are thus discriminant of the various typologies of red stones.

L'Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC) del Consiglio Nazionale delle Ricerche, nel corso delle campagne 2013-2015, ha condotto lo studio dello stato di conservazione dei materiali costitutivi dell'Edificio A e ha proceduto all'individuazione dei meccanismi chimico-fisici responsabili delle fenomenologie di degrado in atto. Per perseguire questi obiettivi sono state utilizzate sia metodologie diagnostiche applicate direttamente in situ, sia metodologie che prevedono il prelievo di campioni, da analizzare successivamente in laboratorio. La valutazione analitica dell'entità del degrado del materiale, come anche la definizione dei processi chimico-fisici che lo regolano, sono parametri imprescindibili di cui tener conto per la definizione di qualsiasi futuro protocollo per la conservazione del monumento.

The tomb of Seti I (KV17) is a magnificent example of New Kingdom' funerary architecture. With its ten rooms and seven corridors with polychrome reliefs of excellent quality, it is among the longest and most spectacular tombs in the Valley of the Kings. Gian Battista Belzoni discovered it in 1817, and he immediately realized the importance of his discovery, describing it "the principal, the most perfect and splendid monument in that country". The opening began a long degenerative process, since the following year, when a flood caused the fall of fragments from walls and ceilings. The Franco-Tuscan expedition 1828-29, led by Jean François Champollion and Ippolito Rosellini studied the tomb. The scholars remarked the freshness of paintings but also their increasing decay. Champollion wrote: "[...] Mais cette belle catacombe dépérit chaque jour. Les piliers se fendent et se délitent; les plafonds tombent en éclats, et la peinture s'enlève en écailles". They decided to remove some reliefs portions that, with thousands of other artifacts, were sent to France (Louvre) and Tuscany, converging in the collections of the future (1855) Egyptian Museum in Florence. Since then the hypogeum has been investigated, documented and restored (Howard Carter, 1903). Decorations removed from Lepsius (1842-45) are now in the Neues Museum of Berlin. The tomb suffers many forms of deterioration: damage of attempts made to remove paintings or track down hidden doors, color deterioration due to natural discoloration, to smoke of candles and torches, but also to wet casts performed by the first scholars (Belzoni, Wilkinson), loss of material. Despite recent conservation works (American Research Center, 1996-2000) mechanical and humidity stress due to tourist flows have accelerated the decay of the tomb, which is currently closed. As part of a collaboration between the Egyptian Museum in Florence, the University of Florence and CNR, a survey project was launched, with non-invasive methods, on the fragments from the Seti I tomb, in Florence. The primary goal is to achieve the best level of documentation, knowledge of the material history and conservation assessment of these artifacts. The approach was tested on a case study to define an integrated protocol of investigation and to verify its potential application to any other pharaonic architectural fragments. We present the results of investigations on the fragment exhibited in Room V (inv. n. 2468), coming from a passage connecting the chamber with four pillars (F) to the corridor G. Here the rock was shaped so as to create a door (height 2.70 m, width 2.09 m, length 1,05 m). Two identical rectangular scenes were carved on the jambs, in which the goddess Hathor welcomes the King handing him the Menat necklace, both removed by Champollion and Rosellini. The fragment of Florence is from the left jamb (SE), its opposite, now in the Louvre (inv. No. B.7) from the right one (NW). The width of both (1.05 m) corresponding to the depth of jambs, indicates that they were completely removed. The rectangles were cut at different heights (Florence: 2,60 m, Paris: 2.26 m), leaving out the remaining surface between it and the sloped ceiling and floor. The current arrangement of the piece, walled and placed on a stand 70 cm high, dates back to the reorganization of Ernesto Schiaparelli (1880). The relief has typical characteristics of the New Kingdom architectural decoration. On the cut and smoothed limestone surface the outlines of the drawing were sketched (visible in the unfinished room "Fa"). Sculptors performed then the relief by lowering the background area between the figures. After finishing, they layed a preparatory layer which could receive the painting mixture. The state of preservation appears mediocre: the painting layers rise in flakes, missing in more points and on the entire surface there are traces of surface deposits. The overall tone is darker compared to the restored piece of Louvre. The survey campaign was based on a first phase of morphological knowledge of the object. A 3D survey was performed with photogrammetric processing software of HD images. The model obtained was the basis for investigation and it is a potential support to interactive implementable further mappings. The surface was divided into squares (10x10 cm) to select the sample areas on which to focus targeted insights. The parameters choosen for selection are: color palette, amount of cutting traces, surface deposits, possible repaintings, decay phenomena, loss of parts and exposure of underlying layers. A detailed survey was carried out on the samples with micro-photogrammetry. A next step was the observation and documentation in raking light surface, to investigate barely visible traces, faults and morphological characters. The stratigraphic readings identified some of the relations between portions visually homogeneous. The characterization of materials was made by punctual or mapping macroanalysis, using the IS techniques (imaging spectroscopy). Investigations were carried out with photographic infrared (IR), false color infrared, UV fluorescence, visible induced luminescence (VIL), portable digital microscope and single spots techniques, X-ray fluorescence (XRF), spectroscopy reflectance with optical fiber (FORS), multi-spectral imaging. The results focus some steps of the history of the object: standard methods and punctual solutions in the realization of the reliefs, tools and processing of carving and finishing limestone. Surveys identified the binder of the preparatory layers and the pigments of the original tempera and subsequent interventions. The micro-mapping of brush marks allowed us to clarify some aspects of the painting technique. Another phase of the study involved the analysis of the transformation traces (additions and subtractions): nature and dynamics of the formation of deposits (carbon black, surface treatments) but also the loss and removal of material. The chronological sequences of the material traces summarize some phases of the life cycle of the relief in and out of the tomb. At last, the degenerative phenomena and their status were identified, distinguishing the ongoing ones from the previous. The study done opens up many research directions: on the one hand the systematic completion of the survey and insights needed on the object itself; on the other the possibility of complementary surveys, such as the use of geophysical methods to clarify the technological articulation of the current arrangement and the presence of internal faults or the monitoring of environmental parameters, that may provide useful data on the nature and stability of the decay phenomena. So as to contribute to the knowledge of the original building, the study could be developed in comparison with the Louvre relief, identifying similarities and differences between formal and technological aspects, groped to understand the role of various teams of decorators and successive transformations (the inscriptions on the Hathor's vest in the relief of Louvre are not visible in the Florence one). We could extend the results by developing scientific cooperation projects with institutions involved in the custody of other fragments from the tomb of Seti I.

Pittura Ostiense di I sec. a.C e d.C - Frammenti di intonaco dipinto. Parte I analisi non invasive

Pittura Ostiense di I sec. a.C e d.C - Frammenti di intonaco dipinto. Parte II analisi petrografica degli intonaci

Vaso Medici-Galleria degli Uffizi. Indagini archeometriche sui marmi, osservazione delle superfici ed identificazione dei trattamenti conservative passati

Villino Ximenes, Roma. Indagini per la caratterizzazione dei materiali e dello stato di conservazione

The study of fragments of Byzantine wall paintings regarding the Sanctuary of the Apostle Philip, in Hierapolis of Phrygia, one of the great Hellenistic, Roman and Byzantine cities of south-western Turkey (Pamukkale, Denizli Province), was carried out in the framework of the Marmora Phrygiae project financed by the Italian Ministry of University and Research (MIUR). The plasters decorated the Byzantine church with three naves built over the tomb of the Apostle. The archaeological investigations have recovered the fragments of plaster of the apses and the narthex. This study was firstly performed using a series of non-invasive techniques such as Ultraviolet (UV) fluorescence and Visible Induced Luminescence (VIL) belonging to the multispectral photographic techniques, Fiber Optic Reflectance Spectroscopy (FORS) and portable X-Ray Fluorescence (XRF) spectrometry applied on the fragments of mural paintings. This first set of measurements was conducted in situ at the storage of the Italian Archaeological Mission in Hierapolis where all the excavated materials were stocked. In this way it was possible to have a first characterization and to group by type all investigated fragments. Then, the most representative and interesting samples were sampled for further studies with laboratory techniques such as optical and electronic microscopy, FTIR and X-ray diffraction. The sampled fragments are made with a plaster mainly constituted by lime with straw without aggregate or lime with sand river aggregate. Moreover, it was possible, to observe one or more (up to three) layers of plaster. The pigments used were red ochres and, in few cases, minium for the red, lapislazuli or Egyptian blue for the blue, for the green a mixing of Egyptian blue and green earth, ochres for the yellow and carbon for the black.

analisi ed interpretazione dei risultati ottenuti dalla campagna diagnostica

Il drappo di Arrigo VII - campagna diagnostica dopo la pulitura Indagini in-situ e campionamento

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Analisi dei prelievi effettuati nella Grotta degli Animali della Villa Medicea di Castello Report Tecnico 04/2015/ICVBC/SB, ottobre 2015

Drappo Arrigo VII - Indagini in-situ, campionamento e analisi di laboratorio prima della pulitura Report Tecnico 02/2015/ICVBC/SB, maggio 2015

Biodeterioration processes are correlated with the chemical and geological composition of the material in itself, with the exposure to environmental factors (temperature, humidity, rain, wind, and solar irradiation), and with the frequency and quality of maintaining procedures applied. These factors influence the growth of biological organisms that can determine not only aesthetical alterations (e.g. colored patches, patinas, crusts) of the surface of stone material, but may erode the material by means of both physical and/or chemical processes, leading to alteration of the material integrity. When the material is part of a structural element the consequences of the degradation can affect even the stability of the architecture, a fact particularly evident on the wood beams heavily infested by insects or caries. The control of biodeterioration on Cultural Heritage artifacts includes all the activities used to eliminate degradation/alteration forms induced by the biological activity of colonizers (microorganisms and/or macro-organisms), and, whenever possible, the necessary activities to be implemented to delay/avoid the recolonization. For disinfection of biological colonizations that may induce progressive biodeterioration and associated damages, the chemical methods are available and widely used, sometimes with detrimental effects on the environment. Chemical treatments include liquid biocides and fumigation with gases. The choice of the biocide is regulated by the European Union's Biocidal Products Directive (BPD) (http://ec.europa.eu/environment/biocides/index.htm). The authors' research activity is oriented to propose physical methods as alternatives to classical biocides, in order to avoid the drawbacks correlated with the toxicity of sole biocides which can pose risks to the environment. In this perspective, the idea of using localized microwave heating treatments can be an effective alternative for controlling the biodeteriogens development to the chemical biocides. The use of microwave heating to control biotic agents was already applied in several fields, in particular in the agri-food industry for disinfestation of grain and other seeds from insects, and for sterilization of soil. In this research, the authors present some of the results on the application of a localized microwave heating to treat the biotic agents which infest the surface of stone artifacts. The microwave heating approach has some important advantages over conventional techniques (chemical biocides and mechanical removal) and other physical methods (thermal radiation, UV, gamma rays, laser cleaning), such as: it respects the operator safety, it is environmentally friendly, and has a low-interaction with the substrate thanks to its selective action- with reference to the conventional techniques - treatment extension, colorindependence, and penetration depth - with respect to other physical methods. The evaluation of the efficiency of the method against infesting agents growing on surfaces of monumental stone was studied with relation to the characteristics of the microwave system (as operative conditions, frequency, power, time and temperature of exposure), the type of infestant organism (lichens, fungi, biofilms-associated microorganisms), and the type of stone support (sandstone, marble).

Questo contributo presenta gli studi preliminari e le scelte metodologiche finalizzate all'intervento di restauro dell'impianto decorativo polimaterico della Sala da Pranzo del Villino Ximenes, casa e studio dello scultore Ettore Ximenes (1855-1926), esempio significativo di architettura Liberty a Roma. Questa sala, uno degli ambienti più suggestivi di tutta l'abitazione, è ricca di raffinati particolari e ricercate tecniche esecutive in linea con le correnti moderniste che rispondono al concetto di funzionalità dell'opera d'arte. L'intero ambiente mostrava differenti problematiche conservative, era dunque necessario procedere con una campagna diagnostica preliminare per conoscere le tecniche esecutive e accertare le cause dei differenti stati di degrado. Alle indagini eseguite hanno collaborato esperti in differenti discipline. Come già previsto in fase progettuale, per l'intervento conservativo ci si è orientati verso scelte ecosostenibili con metodologie e prodotti innovativi a minor impatto ambientale nel rispetto dell'opera, dell'operatore e dell'ambiente. L'unità stilistica dell'ambiente, è stata il filo conduttore di questo lavoro che ha avuto come obiettivo la conservazione e il rispetto dell'intera sala affrontando le problematiche inserite nella loro complessità contestuale oltre che dei singoli manufatti.

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The Garden of Villa Guicciardini Corsi Salviati ranks prominently among Italy's historical gardens. Its importance lies chiefly in the presence of various layers that testify to the successive transformations that took place over more than three hundred years from the Renaissance onwards. Earliest records of the villa and garden date back to the early 16th century: in 1502 Simone di Iacopo Corsi purchased from Luca di Andrea Carnesecchi "an estate in the village of San Martino a Sesto, with Master's Abode and Worker's House". The first changes to the villa and garden were made in the mid-17th century, when Giovanni and Lorenzo Corsi commissioned Gherardo Silvani and Baccio del Bianco to redesign the property. Substantial changes were made in particular to the garden, which became much larger and more refined: attention was lavished on the water displays and the architecture was meticulously remodelled. The greatest transformation to the complex as a whole, however, came in the 18th century. From 1708 to around 1750, the villa and garden took on the appearance they retain (in restored form) to this day. The fronts were decorated and embellished with stuccowork; four terraced towers with loggias were added to the corners of the building, complete with balustrades adorned with statues, pinnacles and urns. Two bird houses were created to the west of the main villa building, one known as the loggia del bacchino after the small bronze statue of Bacchus, depicted pouring water into a small pool. The two are connected by a grand wall with, at the centre, a large arch closed by a wooden door with scrolls and urns flanked by two large serena stone statues depicting mythological characters. The geometric flower-bed in front of the villa was laid out in the form it now displays. The restraint of the rectangular layout of the Italian-style garden was replaced by a series of beds that are triangular at the sides nearest the boundary wall, and trapezoid around the central circular pool and bordered by box hedges; the two oval pools near the entrance to the villa were surrounded by concentric flower-beds. The fishpond became rectangular, with a wrought-iron railing spaced by stone blocks supporting flower vases and four impressive, beautifully crafted statues of the seasons at the corners. The rabbit hutch was eliminated to make way for a large circular pool with various water jets at its centre and surrounded by areas of box-lined lawn. The new lemon grove was also positioned to the west, with, in front of it, a small garden with geometrical flower-beds around a circular pool. An imposing iron railing, surmounted by mythological statues, separated the lemon house area from the large circular pool area. Wrought-iron gates were added to the southern wall that closed off the new garden, and a 300-metre-long ragnaia (a wooded area in which nets were laid out to snare birds), comprising a holm-oak wood crossed by paths. Around 1750, when more water was brought to the garden by marquis Antonio, the ragnaia was extended with a brick-built canal to a waterway (featuring thirteen falls) to a hemicyclical pool with two stone dolphins and another small pool with two niches and mosaic decorations in different materials. In the 19th century as the new English taste began to spread in Italy, the garden underwent other major transformations. An artificial lake was built with an island on it containing a rustic hut and ornamental stone bridge. Other changes include those made by marquis Francesco Antonio Corsi Salviati, who dug up the old 18th-century flower-beds to make way for a large collection of palm trees. He introduced and cultivated various exotic plants and became famous throughout Europe for the successful scientific studies he carried out on them; he also built two hothouses for the plants, heated by powerful steam stoves. The botanical focus given by marquis Francesco was continued and developed after his death in 1878 by his son Bardo (1844-1907), who cultivated particular collections of ornamental plants, including citrus trees, rare orchids, palms and miniature Florentine roses. On Bardo's death in 1907 the villa passed to his grandson, count Giulio Guicciardini Corsi Salviati (1887-1958), who abandoned the cultivation of exotic species and restored the garden to its 18th-century appearance, on the basis of archive material in his possession, but without completely destroying the additions and alterations that had been made over the various cultural periods, displaying respect for art in all its forms and re-organising and improving the ornamentation present in the garden. In 1962 the ragnaia was divided into two parts to allow the passage of a road that was being built to facilitate the flow of traffic heading into the town of Sesto Fiorentino. The lemon house, restored in the second half of the 1980s, is now used as a theatre of the avant-garde run by the municipality of Sesto Fiorentino.

The provenance of the marbles used for the five ancient sculptures on display in the Tribune of the Uffizi--the Venere Medici, the Apollo Medici, the Satiro danzante, the Arrotino and the Lottatori--has been determined using a well-established multi-method approach that includes isotopic, petrographic and EPR data. The Arrotino was found to be made of Docimium marble from the Phrygian quarries of Iscehisar, whereas Parian lychnites was used for the other four sculptures. Restorations, including the restoration of the Satiro ascribed to Michelangelo or his school, primarily used Pentelicon marble. The Lottatori, however, underwent multiple restorations that used a lychnites analytically different from the original stock, as well as Docimium, Carrara and Göktepe marbles. The right arm of the winner, which was considered to be a later addition, turned out to be made using the original marble--lychnites marble. The marble data provide support for the chronology of the sculptures and give insight into the complex sequence of restorations that they underwent.

The scientific research project HYPOGEA started in 2012 by the Pontifical Commission for Sacred Archaeology (PCAS), Vatican, and ICVBC-CNR, Florence, aims to understand the processes of calcium carbonate crystallisations that commonly cover the painted and rock naked surfaces in Roman catacombs, and assess the influence exerted by the environmental conditions and their trend changes. Microclimate monitoring of the Cubicle of the Twelve Apostles in the catacombs of Saints Mark, Marcellian and Damasus by means of a sensor network is coupled with periodic surface pattern change detection. The latter is carried out by combining non-invasive techniques (e.g., colorimetric measurements and digital micro- photogrammetry) and laboratory investigations (e.g., thin and cross-section, FT-IR, XRD and ESEM analyses) on samples taken from both ancient surfaces and newly applied frescoes. The first outcomes are providing interesting insights into the operational issues involved in the monitoring of such unusual environments, including for instance the choice of the parameters to take into account, as well as the materials to use for in-situ experimentations (e.g., pigments and methods and time of application). Monitoring is assumed here as a mean towards a long-term preservation plan, with the perspective of a feasible balance between the aspects of conservation and those of promotion of this hypogeum painted heritage.

The purpose of this paper is the classification of the main conservation issues characterizing the Dazu Rock Carvings, in particular the Baodingshan (Baoding Moutain) Rock Carvings. The prior analysis starts by applying conservation techniques oriented towards managing and mitigating of changes on the basis of knowledge of the history of the site (by documentation, also of previous restoration), of the state of conservation (by diagnostic analysis), and of results of monitoring risks. The results of the recognition can aid in the assessment of risks faced by World Heritage properties and threats to the integrity of the Outstanding Universal Values.Dazu Rock Carvings are situated in the hinterland of Southwest China in the Dazu district of the Chongqing Municipality, and the Baodingshan rock carvings is situated 20 km northeast from Dazu. They are relatively in good situation, because of the natural and anthropogenic factors in recent years they are suffering from accelerating damage. The main conservation issues are the following: unstable rock mass, water damage, weathering damage, anthropogenic damage. The study provides insight into how a multi-disciplinary approach can aid in heritage documentation and conservation, including stakeholder involvement and training. Moreover, by means of this case study it can be shown that a combination of multi-disciplinary diagnostic approach with digital technologies and the participation of stakeholders in heritage conservation and documentation allows an efficient mapping of buffer zones and risks when dealing withcomplexWorldHeritageproperties.

The decay of mosaics in archaeological sites depends on different causes (physical, chemical and mechanical), however a relevant role in the conservation of mosaics is related to the composition and structure of the mortars where the tesserae are embedded. These mortars, in fact, may contribute to the release and transport of soluble salts, transport of water and detachment of the tesserae themselves. In this work, on the basis of the problems related to the conservation of mosaics in the archaeological site of villa romana delle Paduline, I-II sec. B.C. (Castiglione della Pescaia - Grosseto - Italy), three different repair mortars useful to embed the tesserae were prepared and their performances tested. In particular the behaviour of these mortars during their preparation, hardening and artificial ageing has been checked. The colour changes of the mortars during hardening and ageing (determined by chromatic test), the water vapour permeability, the cohesion properties (by Drilling Resistance Measurement System) and durability to artificial ageing (thermo-hygrometric changes in presence of water or salt solution uptake) were determined.