Distribution Drivers of the Alien Butterfly Geranium Bronze (Cacyreus marshalli) in an Alpine Protected Area and Indications for an Effective Management

Cacyreus marshalli is the only alien butterfly in Europe. It has recently spread in the Gran Paradiso National Park (GPNP), where it could potentially compete with native geranium-consuming butterflies. Our study aimed to (1) assess the main drivers of its distribution, (2) evaluate the potential species distribution in GPNP and (3) predict different scenarios to understand the impact of climate warming and the effect of possible mitigations. Considering different sampling designs (opportunistic and standardised) and different statistical approaches (MaxEnt and N-mixture models), we built up models predicting habitat suitability and egg abundance for the alien species, testing covariates as bioclimatic variables, food plant (Pelargonium spp.) distribution and land cover. A standardised approach resulted in more informative data collection due to the survey design adopted. Opportunistic data could be potentially informative but a major investment in citizen science projects would be needed. Both approaches showed that C. marshalli is associated with its host plant distribution and therefore confined in urban areas. Its expansion is controlled by cold temperatures which, even if the host plant is abundant, constrain the number of eggs. Rising temperatures could lead to an increase in the number of eggs laid, but the halving of Pelargonium spp. populations would mostly mitigate the trend, with a slight countertrend at high elevations

Raman spectroscopy discriminates malignant follicular lymphoma from benign follicular hyperplasia and from tumour metastasis

Raman spectroscopy is a non-destructive label-free technique providing biochemical tissue fingerprint. The objective of the present work was to test if Raman spectroscopy is a suitable tool to differentiate lymph nodes affected by different conditions, such as reactive follicular hyperplasia (benign), follicular lymphoma (low grade primary tumour), diffuse large B cell lymphoma (high grade primary tumour) and tumour metastasis (secondary tumours). Moreover, we tested its ability to discriminate follicular lymphomas by the tumour grade and the BCL2 protein expression. Lymph nodes collected from 20 patients, who underwent surgery for suspected malignancy, were investigated. Imaging of tissue areas from about 400 µm2 up to 2 mm2 was performed collecting Raman maps containing thousands of spectra. Partial least squares discriminant analysis (PLS-DA) - a bilinear classification method - was used to calculate lymph node classification models, in order to discriminate at first between benign and malignant tissues and successively among cancer types, grades and the BCL2 protein expression. This proof-of-concept study paves the way for the development of clinical optical biopsy tools for lymph node cancer diagnosis, complementary to histopathological assessment

Realgar and Light

Abstract Light, necessary for viewing a work of art, as it involves the transmission of energy, it can damage the artwork. Nowadays, the most common methods for controlling light are based on the control of the overall lighting intensity. In particular, museum lighting guidelines recommend to limit the time of illumination or to remove wavelengths of light to which human eyes are insensitive. This research aims at determining how lighting systems can be standardized and developed, by studying the interaction between light and the materials constituting cultural heritage. An interesting case-study was considered as starting point: the arsenic sulphides photo-oxidation induced by visible light. In particular, among arsenic sulphides, realgar photo-degradation was studied, as this pigment was used since antiquity. Light transforms realgar (red mineral, As4S4) in arsenolite (white as powder, As2O3) and pararealgar (yellow, As4S4). The process is not completely clarified so far. This study deepens the comprehension of the realgar degradation process and determines the ability of different halogen lamps and a LED lamp, used in museum exhibitions, to induce photodegradation of pigments The study was carried out by means of FT-IR, micro-Raman spectroscopy, XRD and spectra colorimeter analysis.Light, necessary for viewing a work of art, as it involves the transmission of energy, it can damage the artwork. Nowadays, the most common methods for controlling light are based on the control of the overall lighting intensity. In particular, museum lighting guidelines recommend to limit the time of illumination or to remove wavelengths of light to which human eyes are insensitive. This research aims at determining how lighting systems can be standardized and developed, by studying the interaction between light and the materials constituting cultural heritage. An interesting case-study was considered as starting point: the arsenic sulphides photo-oxidation induced by visible light. In particular, among arsenic sulphides, realgar photo-degradation was studied, as this pigment was used since antiquity. Light transforms realgar (red mineral, As4S4) in arsenolite (white as powder, As2O3) and pararealgar (yellow, As4S4)

Optical Sensors for Vapors, Liquids, and Biological Molecules Based on Porous Silicon Technology

The sensing of chemicals and biochemical molecules using several porous silicon optical microsensors, based both on single-layer interferometers and resonant-cavity-enhanced microstructures, is reported. The operation of both families of sensors is based on the variation of the average refractive index of the porous silicon region, due to the interaction with chemical substances either in vapor or liquid state, which results in marked shifts of the device reflectivity spectra. The well established single-layer configuration has been used to test a new chemical approach based on Si-C bonds for covalent immobilization of biological molecules, as probe, in a stable way on the porous silicon surface. Preliminary results on complementary oligonucleotide recognition, based on this technique, are also presented and discussed. Porous silicon optical microcavities, based on multi- layered resonating structures, have been used to detect chemical substances and, in particular, flammable and toxic organic solvents, and some hydrocarbons. The results put in evidence the high sensitivity, the reusability, and the low response time of the resonant-cavity-enhanced sensing technique. The possibility of operating at room temperature, of remote interrogation, and the absence of electrical contacts are further advantages character- izing the sensing technique

From Thioxo Cluster to Dithio Cluster: Exploring the Chemistry of Polynuclear Zirconium Complexes with S,O and S,S Ligands

Three different zirconium thio and oxothio clusters, characterized by different coordination modes of dithioacetate and/or monothioacetate ligands, were obtained by the reaction of monothioacetic acid with zirconium <i>n</i>-butoxide, Zr(OⁿBu)₄, in different experimental conditions. In particular, we isolated the three polynuclear Zr₃(μ₃-SSSCCH₃)₂(SSCCH₃)₆·2ⁿBuOH (<b>Zr</b>_<b>3</b>), Zr₄(μ₃-O)₂(μ−η¹-SOCCH₃)₂(SOCCH₃)₈(OⁿBu)₂ (<b>Zr</b>_<b>4</b>), and Zr₆(μ₃-O)₅(μ-SOCCH₃)₂(μ-OOCCH₃)(SOCCH₃)₁₁(ⁿBuOH) (<b>Zr</b>_<b>6</b>) derivatives, presenting some peculiar characteristics. <b>Zr</b>_<b>6</b> has an unusual star-shaped structure. Only sulfur-based ligands, viz., chelating dithioacetate monoanions and an unusual ethane-1,1,1-trithiolate group μ₃ coordinating the Zr ions, were observed in the case of <b>Zr</b>_<b>3</b>. 1D and 2D NMR analyses confirmed the presence of differently coordinated ligands. Raman spectroscopy was further used to characterize the new polynuclear complexes. Time-resolved extended X-ray absorption fine structure measurements, devoted to unraveling the cluster formation mechanisms, evidenced a fast coordination of sulfur ligands and subsequent relatively rapid rearrangements

Raman Spectroscopy Applied to Parathyroid Tissues: A New Diagnostic Tool to Discriminate Normal Tissue from Adenoma

Primary hyperparathyroidism is an endocrine disorder characterized by autonomous production of parathyroid hormone. Patients with the symptomatic disease should be referred for parathyroidectomy. However, the distinction between the pathological condition and the benign one is very challenging in the surgical setting; therefore, accurate recognition is important to ensure success during minimally invasive surgery. At present, all intraoperative techniques significantly increase surgical time and, consequently, cost. In this proof-of-concept study, Raman microscopy was used to differentiate between healthy parathyroid tissue and parathyroid adenoma from 18 patients. The data showed different spectroscopic features for the two main tissue types of healthy and adenoma. Moreover, the parathyroid adenoma subtypes (chief cells and oxyphil cells) were characterized by their own Raman spectra. The partial least-squares discriminant analysis (PLS-DA) model built to discriminate healthy from adenomatous parathyroid tissue was able to correctly classify all samples in the calibration and validation data sets, providing 100% prediction accuracy. The PLS-DA model built to discriminate chief cell adenoma from oxyphil cell adenoma allowed us to correctly classify >99% of the spectra during calibration and cross-validation and to correctly predict 100% of oxyphil and 99.8% of chief cells in the external validation data set. The results clearly demonstrate the great potential of Raman spectroscopy. The final goal would be development of a Raman portable fiber probe device for intraoperative optical biopsy, both to improve the surgical success rate and reduce surgical cost