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Near-infrared (NIR) luminescence thermometry has been brought to the fore as a reliable approach for remote thermal sensing and imaging. Lanthanide (Ln3+)-based nanophosphors are often proposed as NIR nanothermometers of choice. However, the combination of Ln3+ with transition metal (TM) ions has recently emerged as a strategy to introduce additional emission bands and/or TM ↔ Ln3+ energy transfer pathways whose temperature dependence can be harnessed to increase the sensitivity of the thermometric approach. Yet, the examples of the combination of luminescence nanothermometers working in the NIR and hosting simultaneously TM and Ln3+ are scarce, leaving plenty of space for the exploration of these systems. Herein, we report on the preparation and optimization of the thermometric performance of Ba3(VO4)2:Mn5+,Nd3+ nanophosphors. The different temperature dependences of the emission intensity of the two doped luminescent centers allow using the ratio between Mn5+ and Nd3+ as a reliable thermometric parameter with a relative thermal sensitivity of 1% K−1 close to room temperature. We then showcase the suitability of this nanophosphor for employment in 2D NIR luminescence thermal imaging. Lastly, we critically evaluate the possibility of using this thermal imaging approach through opaque media with the help of phantoms with tissue-like optical properties. As expected, a loss of reliability of the thermometric method is observed due to tissue-induced photon scattering and absorption that differentially affect the emission of Mn5+ and Nd3+. Overall, the reported results underscore the good performance of the newly developed nanothermometer, while consolidating the call for the use of luminescence nanothermometers working in the time-domain (rather than in the spectral domain) for deep-tissue thermal readout/imaging.

This work examines the possible behaviour of Neanderthal groups at the Cueva Des-Cubierta (central Spain) via the analysis of the latter’s archaeological assemblage. Alongside evidence of Mousterian lithic industry, Level 3 of the cave infll was found to contain an assemblage of mammalian bone remains dominated by the crania of large ungulates, some associated with small hearths. The scarcity of post-cranial elements, teeth, mandibles and maxillae, along with evidence of anthropogenic modifcation of the crania (cut and percussion marks), indicates that the carcasses of the corresponding animals were initially processed outside the cave, and the crania were later brought inside. A second round of processing then took place, possibly related to the removal of the brain. The continued presence of crania throughout Level 3 indicates that this behaviour was recurrent during this level’s formation. This behaviour seems to have no subsistence-related purpose but to be more symbolic in its intent.

We introduce the new vertebrate site of La Piquera (Duero Basin, central Iberian Peninsula), provide a detailed description of the lithostratigraphy and present a preliminary faunal list. The fossil vertebrate association includes amphibians (with representatives of the families Salamandridae, Alytidae, Pelodytidae, and Bufonidae), squamate reptiles (with members of the families Agamidae, Lacertidae, Anguidae, Scincidae, Blanidae, ?Erycidae, and Colubridae/Psammophiidae), and mammals (with representatives of the families Soricidae, Erinaceidae, Muridae, Cricetidae, Gerbillidae, Gliridae, Sciuridae, Vespertilionidae, Rhinolophidae, Miniopteridae, Megadermatidae, Leporidae, Prolagidae, and Bovidae). The association indicates an intermediate biostratigraphic position between the southern Iberian sites of Sifón-413 (at about 5.33–5.23 Ma) and Botardo-D (between 4.79 and 4.63 Ma), the new locality being correlated with the earliest Ruscinian (lower part of the MN14 unit). The ecological affinities of the identified small vertebrates suggest the presence of a landscape dominated by open herbaceous meadows in the surroundings of the fossil-site during the earliest Pliocene, with the occasional presence of woodland patches and stable water bodies under relatively dry and warm environmental conditions. La Piquera therefore enhances our knowledge on the vertebrate community recorded in central Iberian Peninsula during the earliest Pliocene. With more than 1200 remains, La Piquera becomes a key locality for the Early Pliocene of southwestern Europe, central Spain, where this time-span is poorly represented.

Lifetime-based luminescence thermometry has been shown to enable accurate deep-tissue monitoring of temperature changes – even at the in vivo level – in a minimally invasive way. However, major limiting factors to the performance of this approach are short lifetimes and poor brightness. These are characteristics, respectively, of semiconductor nanocrystals and lanthanide-doped nanoparticles, of which most luminescent nanothermometers are made. To address these limitations, the composition of luminescent nanothermometers co-doped with transition metal (Mn5+) and Er3+ ions are designed and optimized. The salient features of these nanothermometers are strong, near-infrared emission and long, temperature-dependent photoluminescence lifetime. The potential of these luminescent nanophosphors for thermal sensing is then showcased by monitoring a thermal gradient using a one-of-a-kind piece of equipment designed for lifetime-based luminescence thermometry measurements. The combination of the newly developed nanothermometers and the custom-made instrument allows for obtaining 2D thermal maps both in the absence and presence of tissue phantoms mimicking the optical properties of the skin. The results presented in this study thus provide credible foundations for the deployment of lifetime-based thermometry for accurate deep-tissue thermal mapping at the preclinical level.

Neanderthals have been claimed to have had a selective adaptation to rugged, wooded landscapes that would have partially compensate their high basal metabolic rate and locomotor energetic costs through reducing search time and increasing diet breadth. The archaeological site of the Navalmaíllo rockshelter (Pinilla del Valle, Madrid), located in a mountain environment in central Iberian Peninsula, has been interpreted as a repeated short-term occupation hunting camp by Neanderthal groups, mainly focused on primary access to large bovids and cervids. Navalmaíllo rockshelter has also furnished fish, toads, frogs, tortoises, lizards and snakes remains. This association of amphibians and reptiles suggests a much warmer climate (þ 2.8ºC) for layer F than at present, with similar temperatures during the summer but higher temperatures throughout the remaining months. Rainfall was slightly more abundant (þ180.6 mm) than today, with a more contrasted regime during the year, with rainier winters and drier summers. A two-month period of aridity is observed during summer, representing a similar duration to present-day climatic conditions. Reconstructed landscapes are mainly constituted by open areas with dry grassland and rocky or stony areas, evolving laterally to humid meadows, probably close to the aquatic and peri-aquatic areas, such as rivers or ponds with riverside vegetation. Woodland environments are lso well represented around the site, with medium scrublands to forest formations. Fish complete this reconstruction by documenting the presence of a pre-mountain well-developed river system characterized by relatively cold, permanent, oxygen-rich, and running waters. Such reconstruction is in disagreement with previous pollen interpretation for Layer F that suggested a very open and cold environment. Our new interpretation suggests that the Neanderthal occupation of the Navalmaíllo rockshelter occurred during a somewhat temperate and humid period, probably within the later

Here we report the preliminary results from the 2015–19 s prospecting explorations, excavations, and research from Juan Labranz Cave, a new Quaternary palaeontological deposit rich in mammals that offers information on the faunal context of the southern sub-plateau. This cave is located on the border of the Iberian range, at the Sierra de Valdecabras, Cuenca, at 1.279 metres above sea level. This study includes the first georeferenced digital map of the cave and a preliminary analysis of its chronology, palynology, macro- and microvertebrate palaeontology, and taphonomy. The cave is interpreted as a hyena den, and this would represent one of the highest elevation cavities where the activity of this taxon is recorded. Moreover, we consider this site important and unique because it constitutes one of the very few Pleistocene cave sites in the southern sub-plateau. It is strategically located on the border between the Iberian range and the Tajo Tertiary Basin, at the Júcar River valley, which represents the only great natural corridor that covers hundreds of kilometres and connects two very important palaeoecological areas, the interior of the Iberian Peninsula and the Mediterranean basin.

With the identification of the Jaramillo geomagnetic subchron, the late Early Pleistocene vertebrate succession of the Quibas-Sima section (Quibas karstic complex, southern Spain) represents a time span scarcely recorded in Europe. To complete the existing chronostratigraphic framework published earlier by Piñero et al. (2020), we provide here additional new information about the lithostratigraphy and micromammal succession along the sedimentary sequence. Seven lithostratigraphic units have been differentiated (QS-1 to QS-7) at Quibas-Sima, documenting an almost continuous small mammal record, including representatives of the families Soricidae, Erinaceidae, Rhinolophidae, Vespertilionidae, Arvicolidae, Muridae, Gliridae, Sciuridae, Leporidae and Ochotonidae. The small mammal association indicates that units QS-1 to QS-4 have an intermediate biostratigraphic position between the sites of Fuente Nueva 3 (ca. 1.2 Ma) and Cueva Victoria (ca. 0.9 Ma). New numerical age result from the combined U-series/ESR dating of one equid tooth from QS-3 consistently support the general chronostratigraphic framework based on magnetostratigraphy and biostratigraphic inferences by confirming a post-Olduvai age. Based on an estimation of the sedimentation rate during the Jaramillo subchron, these broad chronological constraints may be confidently refined to approx. 1.1–0.9 Ma for the whole sequence. While we acknowledge the existing uncertainty associated to this age range, it is nevertheless consistent with biostratigraphic evidence indicating that all stratigraphic units most likely do not significantly differ from a chronological point of view. Both independent proxies (biostratigraphy and the sedimentation rate) strongly suggest that the sedimentary sequence covers a relatively short time interval (<200 kyr). These results place the Quibas-Sima sequence as one of the longest and most complete pre-Jaramillo (QS-1) to Jaramillo (QS-2 to QS-5) continental vertebrate succession in Euro