Chemical Fingerprints in an Underwater Archaeological Shipwreck using a Remote Laser-Induced Breakdown Spectroscopy System

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography [1]. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multipulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variefy of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remole LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Remote Laser-Induced Breakdown Spectroscopy in Underwater Archaeology: Identification of Chemical Fingerprints in Shipwrecks

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remote LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Libs in cultural heritage: recognition and identification of objects in an underwater archaeological shipwreck

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Nevertheless, sometimes it is not possible to extract the archaeological material from the marine environment due to size of the sample, the legislation or preservation purposes. In these cases, the in-situ analysis turns into the only alternative for obtaining information. In spite of this demand, no analytical techniques are available for the in-situ chemical characterization of underwater materials. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. To further exploit the inherent advantages of the technology, a mobile fiber-based LIBS platform capable of performing remote measurements up to 50 meters range has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS) 2. The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In the present work, the design and construction considerations of the instrument are reported and its performance is discussed on the basis of the spectral response, the remote irradiance achieved upon the range of analysis and its influence on plasma properties, as well as the effect of the laser pulse duration and purge gas to the LIBS signal. Also, to check the reliability and reproducibility of the instrument for field analysis several robustness tests were performed outside the lab. Finally, the capability of this instrument was successfully demonstrated in an underwater archaeological shipwreck (San Pedro de Alcántara, Malaga).Universidad de Málaga. Campus de Excelencia Internacional Andalucí

Characterization of Laser-Induced Plasmas Of Organic Compounds by spatially- and temporally resolved optical emission spectrometry

The large majority of laser-induced plasmas experiments are performed on metals in air at atmospheric pressure, where recombination mechanisms do not play a significant role, as the primary emission lines of interest are significantly more intense than those derived from recombination with air, particularly those yielding oxides. Due to the large number of electronic transitions commonly attainable on metals, many intense emission lines are recorded and different regions of interest useful for identification and quantification purposes may be assigned. The main difficulties in the interpretation of the molecular emission of species containing C, N, O or H relies on the questions concerning their origin: direct release from native bonds or recombination with ambient constituents. In other words: does the resultant spectrum mimic the structure of a molecule or the molecular information gets lost in the course of the secondary reactions? Considering that the spectrum observed is always a convolution of primary and secondary processes, experiments in vacuum or in controlled atmospheres may help to address such questions. The present work shows detailed experiments where spatially- and temporally-resolved optical emission spectroscopy of laser-produced plasmas on organic compounds has been performed. The experiments cover a pressure range from 1000 mbar to 10-3 mbar that allows a precise observation of the effect of the surrounding atmosphere in the formation of species by recombination.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Differential laser-matter interaction in the ablation of solid samples with laser pulses in the interval between 35 fs – 4 ps.

Our communication is focused on the influence of the pulse width in the laser-matter interaction during laser ablation of solid materials. The experiments were performed with an 80 MHz, 100 nJ, 400 fs Ti-Saphire oscillator, amplified to produce an output of 3,5 mJ at 35 fs and a maximum repletion rate of 1 KHz. Modifications in the stretcher-compressor have allowed the continuous selection of amplified pulses in the range between 35 fs to 4 ps. The pulses are subjected to measurements in the autocorrelation, spectral bandwidth and energy per pulse. A 0.5 m focal-length spectrograph fitted with an intensified CCD or fast single-channel detectors is used to determine the time constants, to establish the fluence threshold, and to record multi-channel spectra from the generated plasmas. Additionally, morphological characterization making use of optical and electron microscopy were performed. The effect of the longer laser pulses in the laser-matter interaction - particularly in the extension of the heat-affected zone - and its implication in depth-profiling studies was also checked. For such purpose, a layered sample with a defined structure was analyzed by laser-induced breakdown spectroscopy under different pulse widths conditions. The effect on the averaged ablation rate, depth resolution and layer mixing will be commented.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Determination of plasmas formation thresholds using femtosecond laser pulses

Our current research line focuses on studying and understanding processes of laser-material interaction in condensed phase using femtosecond lasers in an attempt to improve the analytical performance of laser-based optical emission spectroscopy. An aspect that attracts great interest is the establishment of the energetic demand for both ion and photons formation process after the beam femtosecond laser arrives. The thermoionic emission requires warming the material until its melting point, whereas that the formation of visible plasma need that energy density put into play forms a liquid heated above its critical temperature, that comes out to the surface explosively. Each element in pure form has a particular threshold, which is modified by the matrix effect and the experimental conditions. We are carrying out a systematic study of wide range of metallic samples as well as binary samples, alloys, complex matrices and others, in order to provide a complete view of the process of interesting analytical samples. The core of the experiment is a 80 Mhz, 100 nJ, 400 fs Ti-Saphire oscillator that is additionally subjected to chirped pulse amplification to produce an output of 3,5 mJ at 35 fs and a maximum repletion rate of 1 KHz. Different wavelengths (800, 400 and 266 nm) are achievable. An intensified CCD and a dual-state reflectron equipped with a cassegrain reflective optics are used for the analysis of the photons and ion generated after laser irradiation

Service-learning educational approach for undergraduate students: development of an outreach workshop for high school students

In the last decade, research institutes and universities have strengthened the development of outreach activities in the biomedical field, involving researchers and professors as well as graduate students, but with little or no implication of undergraduate students. However, the development of this type of activities, using the Service-Learning educational approach, could be a valuable tool that would manage the acquisition of learning competencies by undergraduate students of Health Science Degrees and would put science at the service of society. In this project, we present the development of the workshop entitled “Exploring the human body”, in which 205 students in their first and second year of a Degree in Nursing or Medicine (University of Málaga, Spain) acted as mentors of 753 high school students (15 to 16 years old) in several school years (since 2016-2017, excluding 2019-2020 and 2020-2021 due to the COVID-19 pandemic). The workshop consisted of five work stations. Each station featured a set of different experiments and activities that were designed to teach the multiple levels by which the human body, and particularly the nervous system, can be studied: biomolecules, cells, tissues, organs and systems. Both high school and undergraduate students gave an evaluation of the workshop via questionnaires (Likert scale-based and short-answer questions) and a debriefing with the university professors. Data showed an overall score of 4.6 out of 5 points for the workshop by both high school and undergraduate students. In addition, undergraduate students pointed out that their participation had a positive impact on their academic background (4.8 out of 5 points), mainly due to the improvement of their oral communication skills (78 students) and self-confidence (58 students).Universidad de Málaga. Servicio de Publicaciones y Divulgación Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Table1_Teaching the physiology of the human body in non-formal spaces: pilot experience of a Service-Learning methodology and the interaction between students of different educational levels.DOCX

Research institutes and universities have strengthened the development of biomedicine outreach activities, constituing a non-formal education system of science literacy, although with little commitment from undergraduate students. However, as a Service-Learning methodology, these outreach activities could work as a tool for the acquisition of skills by students of Health Science Degrees. Described here is the development of the workshop entitled “Exploring the human body” at the Biodonostia Health Research Institute and the pilot experience of its implementation as a Service-Learning activity at the University of Málaga. Firstly, 359 secondary education students were mentored by Ph.D. students through a 5-station workshop with experiments and activities related to the physiology of the human body. Then, 301 undergraduate students of Medicine and Nursing Degrees advised 965 secondary education students. Both groups of students assessed the workshop via questionnaires and a debriefing. The data showed an overall score of 4.6 out of 5 for the workshop. Undergraduate students reported a positive impact on their academic background (4.8 out of 5), mainly due to the improvement of oral communication skills (34%). Therefore, this methodology could be a valid and applicable tool to develop the cross-disciplinary competences of undergraduate students.</p

NCAPH drives breast cancer progression and identifies a gene signature that predicts luminal a tumour recurrence.

BACKGROUND: Luminal A tumours generally have a favourable prognosis but possess the highest 10-year recurrence risk among breast cancers. Additionally, a quarter of the recurrence cases occur within 5 years post-diagnosis. Identifying such patients is crucial as long-term relapsers could benefit from extended hormone therapy, while early relapsers might require more aggressive treatment. METHODS: We conducted a study to explore non-structural chromosome maintenance condensin I complex subunit Hs (NCAPH) role in luminal A breast cancer pathogenesis, both in vitro and in vivo, aiming to identify an intratumoural gene expression signature, with a focus on elevated NCAPH levels, as a potential marker for unfavourable progression. Our analysis included transgenic mouse models overexpressing NCAPH and a genetically diverse mouse cohort generated by backcrossing. A least absolute shrinkage and selection operator (LASSO) multivariate regression analysis was performed on transcripts associated with elevated intratumoural NCAPH levels. RESULTS: We found that NCAPH contributes to adverse luminal A breast cancer progression. The intratumoural gene expression signature associated with elevated NCAPH levels emerged as a potential risk identifier. Transgenic mice overexpressing NCAPH developed breast tumours with extended latency, and in Mouse Mammary Tumor Virus (MMTV)-NCAPHErbB2 double-transgenic mice, luminal tumours showed increased aggressiveness. High intratumoural Ncaph levels correlated with worse breast cancer outcome and subpar chemotherapy response. A 10-gene risk score, termed Gene Signature for Luminal A 10 (GSLA10), was derived from the LASSO analysis, correlating with adverse luminal A breast cancer progression. CONCLUSIONS: The GSLA10 signature outperformed the Oncotype DX signature in discerning tumours with unfavourable outcomes, previously categorised as luminal A by Prediction Analysis of Microarray 50 (PAM50) across three independent human cohorts. This new signature holds promise for identifying luminal A tumour patients with adverse prognosis, aiding in the development of personalised treatment strategies to significantly improve patient outcomes