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The accurate retrieval of Solar-Induced chlorophyll Fluorescence (SIF) is a pivotal target for Earth Observation since SIF can be easily monitored through optical remote sensing and provides unique information concerning the vegetation health status. Here, we propose i-φ-MaLe (metti il nome per esteso), a novel algorithm, which couples the Fourier analysis with a supervised machine learning-based procedure trained with the atmosphere-canopy radiative transfer (RT) SCOPE model. i-φ-MaLe is the first method able to simultaneously retrieve, from the vegetation reflectance spectra, the Top Of Canopy SIF spectrum, the SIF spectrum corrected for leaf/canopy reabsorption (i.e. at photosystem level), the quantum efficiency (Fqe) and three canopy-related biophysical parameters (Leaf Area Index - LAI, Chlorophyll content - Cab and APAR) in few milliseconds. Validation procedures, based on the analysis of RT simulations, demonstrated that i-φ-MaLe, in experimental conditions (signal to noise ratio – SNR >= 500), estimates each biophysical parameter and SIF spectrum with a relative root mean square error (RRMSE) lower than 5%. In order to investigate the seasonal and daily dynamics of SIF, LAI, Cab, Fqe and APAR, the method has been also applied to field experimental data collected in the context of the AtmoFLEX and FLEXSense ESA campaigns, both at top-of-canopy (TOC) and tower (~100 meters) levels. Concerning the TOC scenario, the retrieved annual dynamic for SIF spectra has been compared with the results obtained by inversion-based methods, showing a good consistency amongthe different approaches (RRMSE ~ 10%). Moreover, SIF daily and annual dynamics, retrieved by excluding the oxygen spectral bands affected by the atmospheric reabsorption, have been investigated for high tower measurements. . In this context, i-φ-MaLe provided promising results that can integrate and possibly overcome complex and computationally expensive atmospheric compensation techniques actually needed to retrieve fluorescence from oxygen absorptions bands. This study demonstrates a promising potential to exploit ground and tower spectral measurements with advanced processing algorithms, for improving our understanding on the link between canopy structure and physiological functioning of plants. Moreover, i-φ-MaLe can be straightforwardly employed to process reflectance spectra and open new perspectives in fluorescence retrieval at different scales.

The flap of bendable structures under continuous flow impacts a variety of fields, ranging from energy harvesting to active mixing in microfluidic devices. Similar physical principles determine the flapping dynamics in a variety of systems with different sizes, but a thorough investigation of the bending dynamics at the microscale is still lacking. We employ here two-photon laser polymerization to fabricate elongated proteinaceous flexible microstructures directly within a micro-capillary and we characterize their bending dynamics. The elastic properties of the microstructures with different (circular and square) cross-sections are tested by Atomic Force Microscopy and by studying the deflection-flow dependence in microfluidic experiments at intermediate Reynolds numbers (Rey ≲ 150). The retrieved Young's modulus of the fabricated matrix (100 kPa ≤ E ≤ 4 MPa) falls in the range of most typical biological tissues and solely depends on the laser fabrication intensity. The elastic constant of the microstructures falls in the range of 0.8 nN μm−1 ≤ k ≤ 50 nN μm−1, and fully agrees with the macroscopic Euler Bernoulli theory. For soft microstructures (0.8 nN μm−1 ≤ k ≤ 8 nN μm−1) we reveal undamped bending oscillations under continuous microfluidic flow, corresponding to ∼10% of the total structure deflection. This behavior is ascribed to the coupling of the viscoelasticity and non-linear elasticity of the polymer matrix with non-linear dynamics arising from the time-dependent friction coefficient of the bendable microstructures. We envision that similar instabilities may lead to the development of promising energy conversion nanoplatforms.

The Ras/cAMP/PKA pathway is one of the best studied signalling pathway in the budding yeast that regulates cellular responses to nutrients availability and stress. The cAMP levels and the PKA activity are also subjected to a strong negative feedback that operates either through the activity of the phosphodiesterase Pde1 and also on the amount of Ras2-GTP. We have previously made and simulated a dynamic model of the whole pathway and our results suggest the existence of stable oscillatory states that depend on the activity of the RasGEF (Cdc25) and RasGAP (Ira proteins) (Pescini et al. Biotechnol Adv 30, 99-107, 2012). Stochastic oscillations related to activity of the pathway were reported by looking at the nuclear localization of the trascription factors Msn2 and Msn4 (Gamedia-Torres et al. Curr Biol 17, 1044-9, 2007). In particular Medvedik et al. (PloS Biol 5, 2330-41, 2007) reported stable oscillations of the nuclear accumulation of Msn2 in condition of limited glucose availabiliy.We were able to reproduce the periodic accumulation of Msn2-GFP protein in yeast cells under condition of limiting glucose, and we tried to detect also in the same condition oscillations of cAMP levels in single yeast cells. We used a specific Fluorescence Resonance Energy Transfer (FRET) sensor based on a fusion protein between CFP-EPAC-YFP expressed in yeast cells. The FRET between CFP and YFP is controlled by cAMP concentration. This sensor allows us to monitor changes in cAMP concentrations in single yeast cell for a relative long time and a peak of cAMP was normally detected after addition of glucose to derepressed cells (Colombo et al. Biochem Biophys Res Commun 487, 594-99, 2017). Using this method we were able to detect noisy oscillations of cAMP levels in single yeast cells under condition of nutritional stress caused by limiting glucose availability (0.1%). We used Spectral analysis to discriminate between true oscillations and random noise. The oscillations were characterized by period of about 4-5 min, close to that observed for Msn2-GFP oscillations.

Cryptococcus neoformans is an opportunistic fungal pathogen known for its remarkable ability to infect and subvert phagocytes. This ability provides survival and persistence within the host and relies on phenotypic plasticity. The viable but nonculturable (VBNC) phenotype was recently described in C. neoformans, whose study is promising in understanding the pathophysiology of cryptococcosis. The use of fluorescent strains is improving host interaction research, but it is still underexploited. Here, we fused histone H3 or the poly(A) binding protein (Pab) to enhanced green fluorescent protein (eGFP) or mCherry, obtaining a set of C. neoformans transformants with different colors, patterns of fluorescence, and selective markers (hygromycin B resistance [Hyg

Cycloparaphenylenes, being the smallest segments of carbon nanotubes, have emerged as prototypes of the simplest carbon nanohoops. Their unique structure-dynamics-optical properties relationships have motivated a wide variety of synthesis of new related nanohoop species. Studies of how chemical changes, introduced in these new materials, lead to systems with new structural, dynamics and optical properties, expand their functionalities for optoelectronics applications. Herein, we study the effect that conjugation extension of a cycloparaphenylene through the introduction of a satellite tetraphenyl substitution has on its structural and dynamical properties. Our non-adiabatic excited state molecular dynamics simulations suggest that this substitution accelerates the electronic relaxation from the high-energy band to the lowest excited state. This is partially due to efficient conjugation achieved between specific phenyl units as introduced by the tetraphenyl substitution. We observe a particular exciton redistribution during relaxation, in which the tetraphenyl substitution plays a significant role. As a result, an efficient inter-band energy transfer takes place. Besides, the observed phonon-exciton interplay induces a significant exciton self-trapping. Our results encourage and guide the future studies of new phenyl substitutions in carbon nanorings with desired optoelectronic properties.

Accessory left atrial cords are fibroelastic structures found in the left atrium. Left atrial cords may be associated with mitral valve disease, atrial fibrillation, stroke, and other congenital left-side anomalies.We presented the case of a man with severe Mitral Regurgitation and two accessories left atrial cords attached to P2 scallop by a single tendon and performed a literature review using PUBMED/MEDLINE, Web of Science, and EMBASE databases on December 4, 2021.According to our review, accessory left atrial cords were found more frequently in women (36 patients, 62%), more frequently attached to the mitral valve (66% of reports) and mitral regurgitation was the most frequently reported pattern of mitral valve disease (64.2%). No other cases of double left atrial cords attached to P2 segment were found.Accessory left atrial chords may be related to mitral valve disease and other left-side congenital abnormalities. These structures were found more frequently in females and A2 insertion was the most frequently observed pattern in the review.

Polymer-based guest-host systems represent a promising class of materials for efficient light-emitting diodes. The energy transfer from the polymer host to the guest is the key process in light generation. Therefore, microscopic descriptions of the different mechanisms involved in the energy transfer can contribute to enlighten the basis of the highly efficient light harvesting observed in this kind of materials. Herein, the nature of intramolecular energy transfer in a dye-end-capped conjugated polymer is explored by using atomistic nonadiabatic excited-state molecular dynamics. Linear perylene end-capped (PEC) polyindenofluorenes (PIF), consisting of n (n = 2, 4, and 6) repeat units, i.e., PEC-PIFn oligomers, are considered as model systems. After photoexcitation at the oligomer absorption maximum, an initial exciton becomes self-trapped on one of the monomer units (donors). Thereafter, an efficient ultrafast through-space energy transfer from this unit to the perylene acceptor takes place. We observe that this energy transfer occurs equally well from any monomer unit on the chain. Effective specific vibronic couplings between each monomer and the acceptor are identified. These oligomer → end-cap energy transfer steps do not match with the rates predicted by Forster-type energy transfer. The through-space and through-bond mechanisms are two distinct channels of energy transfer. The former dominates the overall process, whereas the through-bond energy transfer between indenofluorene monomer units along the oligomer backbone only makes a minor contribution.

Background Previous research has shown that the inclusion of patient-reported outcomes measures in the patient’s visit to the oncologists might improve the quality of global health care. The aim of the study was to assess the feasibility, acceptance, and utility perceived by patients and oncologists of health-related quality of life (HRQL) assessments obtained prior to clinical visits, and to evaluate if this has an impact on patient’s well-being in a sample of Spanish-speaking patients from Uruguay. Methods Patients assisted regularly in the Oncology Clinic were randomized into two groups: an intervention group that completed a set of questionnaires (European Organisation for Research and Treatment of Cancer-Quality of Life Questionnaire-C30 (EORTC QLQ-C30) and Hospital Anxiety and Depression Scale using a touch screen device and a control group that did not respond to these questionnaires. At 2 months, the responses of all the participants to the Functional Assessment of Cancer Therapy-General (FACT-G) were collected over a telephone to determine whether there were differences in the HRQL between the intervention and control groups. The graphed scores of the intervention group were included in the clinical history of the patient during consultation. Patients and physicians completed the questionnaires on the usefulness of these measurements. Results In total, 58 patients participated in this study: 36 in the intervention group and 22 in the control group; 65% of the participants were female, and median age was 59 years (18–79). Regarding patients, 97% found the questionnaires easy to complete and thought that they included important questions. As for oncologists, 68.8% used the information and 87.5% found it useful for the consultation. There were no significant differences in the FACT-G scores between the intervention and control groups. Conclusions The routine HRQL assessments using an electronic device prior to the consultations were positively valued by almost all patients and physicians. This could significantly contribute to a better understanding of the patient's overall problems during consultation. These results confirm the benefits of integrating the patient’s self-reported quality of life outcomes into consultations.

Bacterial contamination is a severe issue that affects medical devices, hospital tools and surfaces. When microorganisms adhere to a surface (e.g., medical devices or implants) they can develop into a biofilm, thereby becoming more resistant to conventional biocides and disinfectants. Nanoparticles can be used as an antibacterial agent in medical instruments or as a protective coating in implantable devices. In particular, attention is being drawn to photothermally active nanoparticles that are capable of converting absorbed light into heat. These nanoparticles can efficiently eradicate bacteria and biofilms upon light activation (predominantly near the infrared to near-infrared spectral region) due a rapid and pronounced local temperature increase. By using this approach new, protective, antibacterial surfaces and materials can be developed that can be remotely activated on demand. In this review, we summarize the state-of-the art regarding the application of various photothermally active nanoparticles and their corresponding nanocomposites for the light-triggered eradication of bacteria and biofilms.

Youth mentoring is theorized as a relationship-based intervention in which a strong mentor-mentee bond functions as a mediator of positive outcomes. Given evidence for the importance of a positive relationship, the current study investigated whether differences in mentors' self-reported attachment tendencies (avoidance and ambivalence), Big Five personality traits, and self-efficacy predicted match quality after one academic semester. We also tested whether mentors' experience of conflict in the relationship moderated the relation between these characteristics and match quality. Participants were college student mentors (N = 190) paired with elementary school children identified via teacher and peer reports as highly aggressive. Separate regression analyses indicated that avoidance, openness, and self-efficacy significantly predicted mentor-rated (but not child-rated) match quality in expected directions. Moderator analyses revealed a mixed pattern of results: at low levels of conflict, ambivalence was a negative predictor of match quality, whereas extraversion and agreeableness were positive predictors. At high levels of conflict, openness and conscientiousness were positive predictors of match quality, whereas agreeableness was a negative predictor. The findings suggest it is important for mentoring programs to consider mentor characteristics when screening, training, and matching mentors, particularly in relationships with children identified as aggressive.

The current protocols for biocompatibility assessment of biomaterials, based on histopathology, require the sacrifice of a huge number of laboratory animals with an unsustainable ethical burden and remarkable cost. Intravital microscopy techniques can be used to study implantation outcomes in real time though with limited capabilities of quantification in longitudinal studies, mainly restricted by the light penetration and the spatial resolution in deep tissues. We present the outline and first tests of a novel chip which aims to enable longitudinal studies of the reaction to the biomaterial implant. The chip is composed of a regular reference microstructure fabricated via two-photon polymerization in the SZ2080 resist. The geometrical design and the planar raster spacing largely determine the mechanical and spectroscopic features of the microstructures. The development, in-vitro characterization and in vivo validation of the Microatlas is performed in living chicken embryos by fluorescence microscopy 3 and 4 days after the implant; the quantification of cell infiltration inside the Microatlas demonstrates its potential as novel scaffold for tissue regeneration.

Super-resolution image acquisition has turned photo-activated far-infrared thermal imaging into a promising tool for the characterization of biological tissues. By the sub-diffraction localization of sparse temperature increments primed by the sample absorption of modulated focused laser light, the distribution of (endogenous or exogenous) photo-thermal biomarkers can be reconstructed at tunable ∼10−50 μm resolution. We focus here on the theoretical modeling of laser-primed temperature variations and provide the guidelines to convert super-resolved temperature-based images into quantitative maps of the absolute molar concentration of photo-thermal probes. We start from camera-based temperature detection via Stefan–Boltzmann’s law, and elucidate the interplay of the camera point-spread-function and pixelated sensor size with the excitation beam waist in defining the amplitude of the measured temperature variations. This can be accomplished by the numerical solution of the three-dimensional heat equation in the presence of modulated laser illumination on the sample, which is characterized in terms of thermal diffusivity, conductivity, thickness, and concentration of photo-thermal species. We apply our data-analysis protocol to murine B16 melanoma biopsies, where melanin is mapped and quantified in label-free configuration at sub-diffraction 40 µm resolution. Our results, validated by an unsupervised machine-learning analysis of hematoxylin-and-eosin images of the same sections, suggest potential impact of super-resolved thermography in complementing standard histopathological analyses of melanocytic lesions.

This paper summarizes the main findings of research on education for sustainable development (ESD) at the international level. The context of the research regards educating cities, or local administrations committed to education through all their policies with the purpose of transforming their territories through a human rights approach. The research’s goal is to explore to what extent educating cities are capable of coping with the three ESD challenges faced today: the gap between policy and practice, the lack of a transformative approach and the hegemony of formal education. To do so, we selected three educating cities with an important background on ESD—Barcelona, Changwon and Rosario—and we implemented a case study method. A detailed analysis of all the data obtained reveals that educating cities are suitable frameworks to overcome the current ESD challenges. Their ESD initiatives count on a significant impact on citizenship, by promoting interdisciplinary, intersectorial and participatory processes mainly in informal education settings. Further research needs to be developed in order to draw a broader analysis.

RESUMEN Candida albicans es la levadura más aislada de la cavidad oral de personas con VIH. Sin embargo, el uso de antifúngicos ha incrementado el aislamiento de especies no C. albicans resistentes o con sensibilidad reducida. El objetivo del estudio fue determinar las especies de Candida y la sensibilidad a los antifúngicos de aislamientos de la cavidad bucal de pacientes con VIH, que acudieron al Instituto de Medicina Tropical entre julio a diciembre de 2019. Las levaduras se sembraron en Agar Cromogénico Candida (CONDA®, España) para la identificación presuntiva. Las colonias verdes se identificaron por PCR dúplex y las de coloración distinta o PCR negativa mediante el sistema comercial VITEK®2. La susceptibilidad antifúngica de C. albicans se determinó por VITEK®2, y las no albicans por el método de difusión de discos. De 278 levaduras, C. albicans se aisló en 70,9 %, seguido de C. tropicalis (8,3 %) y C. krusei (5 %). C. albicans presentó 93 % de sensibilidad y 2 % de sensibilidad dosis dependiente al fluconazol; 87 % sensibles y 3 % con sensibilidad intermedia frente a voriconazol; 97, 98 y 100 % sensibilidad a flucitosina, anfotericina B y equinocandinas, respectivamente. C. parapsilosis y C. tropicalis no registraron resistencias a fluconazol y voriconazol. Todos los aislamientos de C. glabrata fueron sensibles dosis dependientes a fluconazol y todos los aislamientos de C. krusei resultaron sensibles a voriconazol. La portación oral de Candida spp. resistentes a azoles podría llevar a fracasos terapéuticos en pacientes con VIH que desarrollen candidiasis orofaríngea. ABSTRACT Candida albicans is the most isolated yeast from the oral cavity of people with HIV. However, the use of antifungals has increased the isolation of non-C. albicans resistant species or those with reduced sensitivity. The objective of the study was to determine the Candida species and the sensitivity to antifungals of isolates from the oral cavity of patients with HIV who attended the Institute of Tropical Medicine between July and December 2019. The yeasts were plated in Candida Chromogenic Agar (CONDA®, Spain) for presumptive identification. Green colonies were identified by duplex PCR and those with different staining or negative PCR using the commercial VITEK®2 system. The antifungal susceptibility of C. albicans was determined by VITEK®2, and non albicans by the disk diffusion method. Of 278 yeasts, C. albicans was isolated in 70.9 %, followed by C. tropicalis (8.3 %) and C. krusei (5 %). C. albicans presented 93 % sensitivity and 2 % dose-dependent sensitivity to fluconazole; 87 % sensitive and 3 % intermediate sensitivity to voriconazole; 97, 98, and 100 % sensitive to flucytosine, amphotericin B, and echinocandins, respectively. C. parapsilosis and C. tropicalis did not register resistance to fluconazole and voriconazole. All C. glabrata isolates were dose-dependently sensitive to fluconazole and all C. krusei isolates were sensitive to voriconazole. The oral carriage of Candida spp. resistant to azoles may lead to therapeutic failures in HIV patients who develop oropharyngeal candidiasis.

The possibility to shape stimulus-responsive optical polymers, especially hydrogels, by means of laser 3D printing and ablation is fostering a new concept of “smart” micro-devices that can be used for imaging, thermal stimulation, energy transducing and sensing. The composition of these polymeric blends is an essential parameter to tune their properties as actuators and/or sensing platforms and to determine the elasto-mechanical characteristics of the printed hydrogel. In light of the increasing demand for micro-devices for nanomedicine and personalized medicine, interest is growing in the combination of composite and hybrid photo-responsive materials and digital micro-/nano-manufacturing. Existing works have exploited multiphoton laser photo-polymerization to obtain fine 3D microstructures in hydrogels in an additive manufacturing approach or exploited laser ablation of preformed hydrogels to carve 3D cavities. Less often, the two approaches have been combined and active nanomaterials have been embedded in the microstructures. The aim of this review is to give a short overview of the most recent and prominent results in the field of multiphoton laser direct writing of biocompatible hydrogels that embed active nanomaterials not interfering with the writing process and endowing the biocompatible microstructures with physically or chemically activable features such as photothermal activity, chemical swelling and chemical sensing.

Male breast cancer (MBC) is a rare condition which, while sharing some similarities with breast cancer in women, has a unique disease profile of its own. Aim: To understand the characteristics of MBC and its management in Uruguay. Patients & methods: Retrospective observational study that included patients diagnosed with MBC. Results: 22 cases of MBC were found. The median age at diagnosis was 62.5 years. Symptoms included self-detected lump in 17 patients (77.3%) and nipple retraction in seven (22.7%). Ductal carcinomas of histological grade 2–3 were found in 20 patients (90.9%) and stage I–II disease was most commonly encountered (15 patients, 68.1%). Neoadjuvant chemotherapy, adjuvant chemotherapy, adjuvant radiotherapy and tamoxifen were offered to 16 (73%), 12 (54.5%), 17 (65.4%) and 20 (90.9%) patients, respectively. Conclusion: MBC behaves and is treated in many aspects like postmenopausal breast cancer. Further multi-institutional, prospective studies are needed for better understanding and management of male breast cancers.

PVA films with embedded either silver nanoparticles (AgNP), NIR-absorbing photothermal gold nanostars (GNS), or mixed AgNP+GNS were prepared in this research. The optimal conditions to obtain stable AgNP+GNS films with intact, long lasting photothermal GNS were obtained. These require coating of GNS with a thiolated polyethylene glycol (PEG) terminated with a carboxylic acid function, acting as reticulant in the film formation. In the mixed AgNP+GNS films, the total noble metal content is &lt, 0.15% w/w and in the Ag films &lt, 0.025% w/w. The slow but prolonged Ag+ release from film-embedded AgNP (8–11% of total Ag released after 24 h, in the mixed films) results in a very strong microbicidal effect against planktonic Escherichia coli and Staphylococcus aureus bacterial strains (the release of Au from films is instead negligible). Beside this intrinsic effect, the mixed films also exert an on-demand, fast hyperthermal bactericidal action, switched on by NIR laser irradiation (800 nm, i.e., inside the biotransparent window) of the localized surface plasmon resonance (LSPR) absorption bands of GNS. Temperature increases of 30 °C are obtained using irradiances as low as 0.27 W/cm2. Moreover, 80–90% death on both strains was observed in bacteria in contact with the GNS-containing films, after 30 min of irradiation. Finally, the biocompatibility of all films was verified on human fibroblasts, finding negligible viability decrease in all cases.

Currently there is a strong demand for novel protective materials with efficient antibacterial properties. Nanocomposite materials loaded with photo-thermally active nanoparticles can offer promising opportunities due to the local increase of temperature upon near-infrared (NIR) light exposure capable of eradicating bacteria. In this work, we fabricated antibacterial films obtained by spraying on glass slides aqueous solutions of polymers, containing highly photo-thermally active gold nanostars (GNS) or Prussian Blue (PB) nanoparticles. Under NIR light irradiation with low intensities (0.35 W/cm2) these films demonstrated a pronounced photo-thermal effect: &Delta, Tmax up to 26.4 &deg, C for the GNS-containing films and &Delta, Tmax up to 45.8 &deg, C for the PB-containing films. In the latter case, such a local temperature increase demonstrated a remarkable effect on a Gram-negative strain (P. aeruginosa) killing (84% of dead bacteria), and a promising effect on a Gram-positive strain (S. aureus) eradication (69% of dead bacteria). The fabricated films are promising prototypes for further development of lightweight surfaces with efficient antibacterial action that can be remotely activated on demand.

We developed an easy and reproducible synthetic method to graft a monolayer of copper sulfide nanoparticles (CuS NP) on glass and exploited their particular antibacterial features. Samples were fully characterized showing a good stability, a neat photo-thermal effect when irradiated in the Near InfraRed (NIR) region (in the so called &ldquo, biological window&rdquo, ), and the ability to release controlled quantities of copper in water. The desired antibacterial activity is thus based on two different mechanisms: (i) slow and sustained copper release from CuS NP-glass samples, (ii) local temperature increase caused by a photo-thermal effect under NIR laser irradiation of CuS NP&ndash, glass samples. This behavior allows promising in vivo applications to be foreseen, ensuring a &ldquo, static&rdquo, antibacterial protection tailored to fight bacterial adhesion in the critical timescale of possible infection and biofilm formation. This can be reinforced, when needed, by a photo-thermal action switchable on demand by an NIR light.

Coherence, signifying concurrent electron-vibrational dynamics in complex natural and man-made systems, is currently a subject of intense study. Understanding this phenomenon is important when designing carrier transport in optoelectronic materials. Here, excited state dynamics simulations reveal a ubiquitous pattern in the evolution of photoexcitations for a broad range of molecular systems. Symmetries of the wavefunctions define a specific form of the non-adiabatic coupling that drives quantum transitions between excited states, leading to a collective asymmetric vibrational excitation coupled to the electronic system. This promotes periodic oscillatory evolution of the wavefunctions, preserving specific phase and amplitude relations across the ensemble of trajectories. The simple model proposed here explains the appearance of coherent exciton-vibrational dynamics due to non-adiabatic transitions, which is universal across multiple molecular systems. The observed relationships between electronic wavefunctions and the resulting functionalities allows us to understand, and potentially manipulate, excited state dynamics and energy transfer in molecular materials., Interference patterns in photoexcited dynamics of many materials have historically been attributed to electronic and vibrational coherences. Here, the authors demonstrate a simple model based on wavefunction symmetry suggesting these coherences originate from non-adiabatic transitions for optically active molecules.

Second Harmonic Generation (SHG) is a label-free imaging method used to monitor collagen organization in tissues. Due to its sensitivity to the incident polarization, it provides microstructural information otherwise unreachable by other intensity based imaging methods. We develop and test a Microscopic Multiparametric Analysis by Phasor projection of Polarization-dependent SHG (μMAPPS) that maps the features of the collagen architecture in tissues at the micrometer scale. μMAPPS retrieves pixel-by-pixel the collagen fibrils anisotropy and orientation by operating directly on two coupled phasor spaces, avoiding direct fitting of the polarization dependent SHG signal. We apply μMAPPS to fixed tissue sections and to the study of the collagen microscopic organization in tumors ex-vivo and in-vivo. We develop a clustering algorithm to automatically group pixels with similar microstructural features. μMAPPS can perform fast analyses of tissues and opens to future applications for in-situ diagnosis of pathologies and diseases that could assist histo-pathological evaluation.

In Saccharomyces cerevisiae the second messenger cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) play a central role in metabolism regulation, stress resistance and cell cycle progression. To monitor cAMP levels and PKA activity in vivo in single S. cerevisiae cells, we expressed an Epac-based FRET probe and a FRET-based A-kinase activity reporter, which were proven to be useful live-cell biosensors for cAMP levels and PKA activity in mammalian cells. Regarding detection of cAMP in single yeast cells, we show that in wild type strains the CFP/YFP fluorescence ratio increased immediately after glucose addition to derepressed cells, while no changes were observed when glucose was added to a strain that is not able to produce cAMP. In addition, we had evidence for damped oscillations in cAMP levels at least in SP1 strain. Regarding detection of PKA activity, we show that in wild type strains the FRET increased after glucose addition to derepressed cells, while no changes were observed when glucose was added to either a strain that is not able to produce cAMP or to a strain with absent PKA activity. Taken together these probes are useful to follow activation of the cAMP/PKA pathway in single yeast cells and for long times (up to one hour).

Second Harmonic Generation (SHG) microscopy has gained much interest in the histopathology field since it allows label-free imaging of tissues simultaneously providing information on their morphology and on the collagen microarchitecture, thereby highlighting the onset of pathologies and diseases. A wide request of image analysis tools is growing, with the aim to increase the reliability of the analysis of the huge amount of acquired data and to assist pathologists in a user-independent way during their diagnosis. In this light, we exploit here a set of phasor-parameters that, coupled to a 2-dimensional phasor-based approach (μMAPPS, Microscopic Multiparametric Analysis by Phasor projection of Polarization-dependent SHG signal) and a clustering algorithm, allow to automatically recover different collagen microarchitectures in the tissues extracellular matrix. The collagen fibrils microscopic parameters (orientation and anisotropy) are analyzed at a mesoscopic level by quantifying their local spatial heterogeneity in histopathology sections (few mm in size) from two cancer xenografts in mice, in order to maximally discriminate different collagen organizations, allowing in this case to identify the tumor area with respect to the surrounding skin tissue. We show that the “fibril entropy” parameter, which describes the tissue order on a selected spatial scale, is the most effective in enlightening the tumor edges, opening the possibility of their automatic segmentation. Our method, therefore, combined with tissue morphology information, has the potential to become a support to standard histopathology in diseases diagnosis.

Mapping flows in vivo is essential for the investigation of cardiovascular pathologies in animal models. The limitation of optical-based methods, such as space-time cross correlation, is the scattering of light by the connective and fat components and the direct wave front distortion by large inhomogeneities in the tissue. Nonlinear excitation of the sample fluorescence helps us by reducing light scattering in excitation. However, there is still a limitation on the signal-background due to the wave front distortion. We develop a diffractive optical microscope based on a single spatial light modulator (SLM) with no movable parts. We combine the correction of wave front distortions to the cross-correlation analysis of the flow dynamics. We use the SLM to shine arbitrary patterns of spots on the sample, to correct their optical aberrations, to shift the aberration corrected spot array on the sample for the collection of fluorescence images, and to measure flow velocities from the cross-correlation functions computed between couples of spots. The setup and the algorithms are tested on various microfluidic devices. By applying the adaptive optics correction algorithm, it is possible to increase up to 5 times the signal-to-background ratio and to reduce approximately of the same ratio the uncertainty of the flow speed measurement. By working on grids of spots, we can correct different aberrations in different portions of the field of view, a feature that allows for anisoplanatic aberrations correction. Finally, being more efficient in the excitation, we increase the accuracy of the speed measurement by employing a larger number of spots in the grid despite the fact that the two-photon excitation efficiency scales as the fourth power of this number: we achieve a twofold decrease of the uncertainty and a threefold increase of the accuracy in the evaluation of the flow speed.

Active thermal imaging is a valuable tool for the nondestructive characterization of the morphological properties and the functional state of biological tissues and synthetic materials. However, state-of-the-art techniques do not typically combine the required high spatial resolution over extended fields of view with the quantification of temperature variations. Here, we demonstrate quantitative far-infrared photo-thermal imaging at sub-diffraction resolution over millimeter-sized fields of view. Our approach combines the sample absorption of modulated raster-scanned laser light with the automated localization of the laser-induced temperature variations imaged by a thermal camera. With temperature increments ∼0.5–5 °C, we achieve a six-time gain with respect to our 350-μm diffraction-limited resolution with proof-of-principle experiments on synthetic samples. We finally demonstrate the biological relevance of sub-diffraction thermal imaging by retrieving temperature-based super-resolution maps of the distribution of Prussian blue nanocubes across explanted murine skin biopsies., Thermal characterization of biological tissues can traditionally provide either large fields of view or high resolution. By the development of super-resolution infrared photo-thermal imaging, the authors reconstruct temperature-based maps of absorptive centers in millimeter-sized biological samples.

Antibacterial treatment is an essential issue in many diverse fields, from medical device treatments (for example prostheses coating) to food preservation. However, there is a need of novel and light-weight materials with high antibacterial efficiency (preferably due to the physical activation). Utilization of photo-thermally active nanoparticles can lead to novel and re-usable materials that can be remotely activated on-demand to thermally eradicate bacteria and mitigate biofilm formation, therefore meeting the above challenge. In this study polyvinyl alcohol (PVA) hydrogel films containing non-toxic and highly photo-thermally active Prussian blue (PB) nanoparticles were fabricated. The confocal microscopy studies indicated a uniform nanoparticle distribution and a low degree of aggregation. Upon near-infrared (NIR; 700 and 800 nm) light irradiation of PVA-PB films, the local temperature increases rapidly and reaches a plateau (up to ΔT ≅ 78 °C), within ≈6-10 s under relatively low laser intensities, I ≅ 0.3 W cm-2. The high and localized increase of temperature on the fabricated films resulted in an efficient antibacterial effect on Pseudomonas aeruginosa (P. aeruginosa) bacteria. In addition, the localized photo-thermal effect was also sufficient to substantially mitigate biofilms growth.

Thermal conductivity measurements play a crucial role in most areas of the applied physical sciences, thereby constantly demanding for new non-invasive methods capable of providing high-resolution spatial mapping of absolute thermal conductivities on heterogeneous samples ranging from solid-state bulk materials to low-dimensionality structures. In this work, we lay the theoretical foundations and provide the experimental demonstration of a novel method for quantitative thermal conductivity mapping at tunable ∼10-μm resolution, by non-contact infrared photo-activated thermography. Starting from Fourier’s heat transfer law, we surmise a universal dependence of the thermal response of a laser-irradiated sample on its thermal conductivity, irrespectively of density and specific heat capacity. We demonstrate such a dependence over the three conductivity decades 0.1–100 W/mK by finite-element numerical simulations, and exploit it for proof-of-principle single-point thermal conductivity measurements on both thermally thick and thermally thin reference solid samples. We exemplify the feasibility of space-resolved measurements on eighteenth-century tin organ pipe fragments, where the product of the thermal conductivity times the sample thickness, imaged at 40-μm sub-diffraction resolution, is pointed out as a relevant parameter for the non-destructive characterization of the sample conservation state. By coupling temperature maps with the extraction of thermal properties at high spatial resolution, our approach significantly expands the capability of state-of-the-art infrared imaging technology in fully capturing the compositional heterogeneity and/or functional state of the imaged materials.

Two‐photon laser writing is used here to fabricate 3D proteinaceous microstructures with photothermal functionality in the near‐infrared spectral region and tunable elasticity. The photo‐cross‐linking is initiated in bovine serum albumin (BSA) by rose bengal or methylene blue and the photo‐thermal effect arises from gold non‐spherically symmetric nanoparticles dispersed in the ink. Massive energy transfer of the plasmonic resonances of the gold nanoparticles to methylene blue prevents effective photo‐crosslinking of BSA. However, stable microstructures with photo‐thermal functionality can be fabricated in the rose bengal proteinaceous inks. On these microstructures, with a gold atom concentration as low as 1% w/w, a highly localized temperature increase can be quickly (≅1 s) reached and maintained under continuous wave laser irradiation at 800 nm. The photothermal efficiency under continuous wave laser irradiation depends on the thickness of the microstructure and can reach 12.2 ± 0.4 °C W−1 These proteinaceous microstructures represent therefore a promising platform for future applications in the fields like physical stimulation of cells for regenerative nanomedicine.