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We investigate electron phonon coupling EPC in the charge density wave CDW phase of VSe2 by Raman spectroscopy, angle resolved photoemission spectroscopy ARPES , and ab initio calculations. Zone folding induced by the 4 4 in plane CDW phase promotes the appearance of a Raman peak at amp; 8764;170cm amp; 8722;1. The suppression of ARPES intensity in parts of the Fermi surface is also a result of CDW induced zone folding and anticrossing of the electron energy bands. The appearance of the new Raman peak is in line with the ARPES observation of a kink feature in the spectral function at the same energy. A self energy analysis yields an EPC constant of amp; 955; 0.3. Our calculations of the EPC are in excellent agreement and reveal that the kink is caused by several optical phonon branches close in energy. Our paper highlights the CDW phase as a means of inducing EPC pathways to optical phonons that directly affect its Raman spectrum

Quantum states of matter combining non-trivial topology and magnetism attract a lot of attention nowadays; the special focus is on magnetic topological insulators (MTIs) featuring quantum anomalous Hall and axion insulator phases. Feasibility of many novel phenomena that \emph{intrinsic} magnetic TIs may host depends crucially on our ability to engineer and efficiently tune their electronic and magnetic structures. Here, using angle- and spin-resolved photoemission spectroscopy along with \emph{ab initio} calculations we report on a large family of intrinsic magnetic TIs in the homologous series of the van der Waals compounds (MnBi$_2$Te$_4$)(Bi$_2$Te$_3$)$_m$ with $m=0, ..., 6$. Magnetic, electronic and, consequently, topological properties of these materials depend strongly on the $m$ value and are thus highly tunable. The antiferromagnetic (AFM) coupling between the neighboring Mn layers strongly weakens on moving from MnBi2Te4 (m=0) to MnBi4Te7 (m=1), changes to ferromagnetic (FM) one in MnBi6Te10 (m=2) and disappears with further increase in m. In this way, the AFM and FM TI states are respectively realized in the $m=0,1$ and $m=2$ cases, while for $m \ge 3$ a novel and hitherto-unknown topologically-nontrivial phase arises, in which below the corresponding critical temperature the magnetizations of the non-interacting 2D ferromagnets, formed by the \MBT\, building blocks, are disordered along the third direction. The variety of intrinsic magnetic TI phases in (MnBi$_2$Te$_4$)(Bi$_2$Te$_3$)$_m$ allows efficient engineering of functional van der Waals heterostructures for topological quantum computation, as well as antiferromagnetic and 2D spintronics.

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim We investigate the N = 9 atoms wide armchair-type graphene nanoribbons (9-AGNRs) by performing a comprehensive spectroscopic and microscopic characterization of this novel material. In particular, we use X-ray photoelectron, near edge X-ray absorption fine structure, scanning tunneling, polarized Raman and angle-resolved photoemission (ARPES) spectroscopies. The ARPES measurements are aided by calculations of the photoemission matrix elements which yield the position in k space having the strongest photoemission cross section. Comparison with well-studied narrow N = 7 AGNRs shows that the effective electron mass in 9-AGNRs is reduced by two times and the valence band maximum is shifted to lower binding energy by ∼0.6 eV. In polarized Raman measurements of the aligned 9-AGNR, we reveal anisotropic signal depending upon the phonon symmetry. Our results indicate the 9-AGNRs are a novel 1D semiconductor with a high potential in nanoelectronic applications.

Quantum mechanics postulates that any measurement influences the state of the investigated system. Here, by means of angle-, spin-, and time-resolved photoemission experiments and ab initio calculations we demonstrate how non-equal depopulation of the Dirac cone (DC) states with opposite momenta in V-doped and pristine topological insulators (TIs) created by a photoexcitation by linearly polarized synchrotron radiation (SR) is followed by the hole-generated uncompensated spin accumulation and the SR-induced magnetization via the spin-torque effect. We show that the photoexcitation of the DC is asymmetric, that it varies with the photon energy, and that it practically does not change during the relaxation. We find a relation between the photoexcitation asymmetry, the generated spin accumulation and the induced spin polarization of the DC and V 3d states. Experimentally the SR-generated in-plane and out-of-plane magnetization is confirmed by the $k_{\parallel}$-shift of the DC position and by the splitting of the states at the Dirac point even above the Curie temperature. Theoretical predictions and estimations of the measurable physical quantities substantiate the experimental results., Comment: 17 pages, 8 figures

Il contesto di riferimento in cui si inserisce il lavoro qui presentato, è quello delle reti di drenaggio urbano che, consentendo con continuità la raccolta e lo smaltimento dei reflui domestici, industriali e/o delle acque urbane di origine meteorica, rappresentano un elemento fondamentale nel benessere di una comunità urbana. Spesso accade che l'integrità e la corretta funzionalità dei sistemi fognari è compromessa da fenomeni di infiltrazione di acque nella rete e/o di fuoriuscite dalla stessa. Entrambi i suddetti fenomeni si ripercuotono non solo sui corpi idrici sotterranei e superficiali ma anche sulle prestazioni degli impianti di trattamento delle acque. La valutazione e il controllo delle reali prestazioni dei propri sistemi fognari costituisce, tra l'altro, un punto cardine della Gestione Integrata dei Sistemi Idrici che in Italia e, in particolar modo nell'Italia meridionale e insulare, è fortemente deficitaria soprattutto nell'impiego pratico di idonee metodologie di analisi e di strumenti tecnici e amministrativi. L'attività di ricerca posta in essere ha avuto lo scopo di mettere a punto strumenti di controllo e di gestione di reti fognarie, efficaci e di semplice impiego cercando anche di colmare il gap metodologico e strumentale. L'attività, pertanto, è stata indirizzata allo sviluppo di una metodologia per la valutazione della vulnerabilità e dell'efficienza di funzionamento delle reti di fognatura che, integrando dati provenienti da monitoraggi ambientali con sistemi GIS e modelli di simulazione idraulica, è in grado di descrivere l'efficienza di funzionamento delle reti di fognatura. Lo studio del GIS specifico per le reti di fognatura in ambito urbano ha condotto alla evidenza che, oltre a contenere informazioni di tipo fisico, doveva contenerne di tipo funzionale. Da qui la scelta, sfruttando gli studi analoghi presenti in letteratura tecnica sulle reti acquedottistiche, di costruire degli indicatori di criticità del sistema fognario in grado di fornire sinteticamente entrambe le informazioni. L'implementazione di ulteriori indici di criticità correlati ai fenomeni di infitrazione ed exfiltrazione ha consentito anche la caratterizzazione dell'interazione sistema fognario-ambiente. Tutte le informazioni raccolte, assieme ai risultati delle elaborazioni, sono confluite in un GIS ottenendo mappe tematiche distinte per ciascuno degli indicatori valutati. Queste ultime, successivamente combinate tra di loro, hanno consentito di ottenere una mappa rappresentativa della distribuzione spaziale delle criticità potenziali complessive. Punto di arrivo della metodologia, infatti, è la realizzazione di mappe di rischio attraverso le quali è possibile perimetrare le zone di rete "critiche" così da ottimizzare tutte le operazioni di pianificazione, manutenzione, riabilitazione, progettazione e ri-progettazione delle infrastrutture di drenaggio urbano. L'acquisizione dell'ampia base di dati di input, necessari all'implementazione del modello di controllo per la localizzazione delle criticità, è avvenuta per buona parte attraverso lo svolgimento di apposite attività. Tra queste, merita di essere annoverata per il suo spiccato carattere innovativo, l'esecuzione di test per la verifica della tenuta di alcuni tronchi della rete fognaria, con la metodologia denominata FELL-41(TM) (Focussed Electrode Leak Location). Nel complesso, il prodotto sviluppato costituisce una buona pratica di supporto nel perseguimento di obiettivi di competitività economica e di sostenibilità ambientale garantendo l'ottimizzazione degli interventi sulle fognature, di protezione delle falde dall'inquinamento e di migliore dell'impianti di depurazione.

The aims of this study were: 1) to perform brain single photon emission computed tomography (SPECT) in anesthetized rats with high resolution cameras (HRC) equipped with parallel hole collimation resolution of about 1 mm (HRC1) and 2 mm (HRC2); 2) to assess when and with which radio-tracer HRC1 SPECT shows advantages over HRC2. Methods. We used two multicrystal HRCs with parallel square hole collimators, whose pure tungsten septa closely fit the crystals, in turn matched with a 4 inch2 position sensitive photomultiplier. HRC1 showed 1.1 mm and HCR2 2.1 mm resolution at collimator contact. HRCs performed 180° semi-circular orbits around the head of rats: image reconstruction occurred with ordered subsets expectation maximization algorithms. Resolution of SPECT was measured with a Derenzo Phantom, resulting 1.4 mm for HRC1 and 2.3 mm for HRC2. Three rats were studied with [99mTc]HMPAO, 3 rats with [99mTc]bombesin (BN) and 48 h later with [123I]ioflupane (DaTSCAN). SPECT studies were reviewed by two experienced operators. Results. Technetium-99m-HMPAO SPECT showed similar images with HRC1 and HRC2. The uptake of BN by amygdale, hippocampus and olfactory tract was detected by both cameras. DaTSCAN SPECT with HRC1 showed detailed image of the tail of the caudatus: this image was not obtained with HRC2. DaTSCAN and BN SPECT showed amygdale with both HRCs. However, only the central nucleus of amygdale takes up DaTSCAN, whereas central, lateral and basolateral amygdaloid nuclei express BN receptors. Only HRC1 SPECT showed amygdale larger with BN than with DaTSCAN. Conclusion. Spatial resolution of 1.4 mm is appropriate to detect selected subcerebral structures.

Aim High resolution scintigraphy ( HRS) can be useful in radio-guided surgery (RGS) and small animal imaging. Devices are generally based on arrays of sensible elements: room temperature semiconductor arrays or scintillating crystals arrays that can be coupled with position sensitive photomultipliers (PSPMT). Here we describe a small Field Of View (FOV) portable cameras based on 1 and 4 inches2 PSPMT. Materials & Methods These cameras show a peculiar crystal- collimator- PSPMT matching that allows the exact positioning of all the scintillating elements inserted in the square holes of a parallel Tungsten collimator. This arrangement ensures no crosstalk of ? rays or light among crystals. The scintillation light emerging from each crystal is revealed by a PSPMT (H8500 or R8520-00-C12). The anodes allow event positioning through the reconstruction of the maximum of the multiplied charge distribution by the centroid algorithm. Data are then selected with an appropriate energy window and transferred to a workstation. We studied the spatial resolution and the homogeneity of two cameras both equipped with 2.4x2.4x5 mm3 CsI (Tl) crystals and a 25 mm long collimator. A thin Plexiglas container filled with 99mTc was used to check homogeneity and pixel identification. A Derenzo phantoms with the diameter of the holes ranging from 2 to 4 mm was positioned at contact, at 1, 2, 3 cm distance from the collimator and filled with 99mTc to assess the camera spatial resolution. Results The energy resolution was 19.1 % FWHM of the 99mTc peak over the whole FOV area. Both cameras showed homogeneity within ± 5% between max and min pixel counts. Pixel identification showed average peak to valley ratio of 20:1. Spatial resolution was 3.3 mm at 1 cm, 4.9 mm at 3 cm, 6.0 mm at 5 cm and 10.9 mm at 10 cm distance. Conclusion Measurement of resolution were performed to foresee the working conditions of HR cameras. Actually when nuclear physicians show to surgeons sentinel nodes or parathyroid glands, they are on contact with the source or at few cm distance. Both detectors were used for RGS and showed hot nodes less than 2 mm large and distant 2.5 mm each other. In several instances a spot detected as single node by Anger camera showed the presence of two near nodes.

Sentinel node (SN) biopsy is an established method for breast cancer staging. Many authors suggested lymphoscintigraphy (LS) in order to indicate the sentinel node; others adopted the vital dye method together with radiocolloids, but only with γ-probe detection during operation without preliminary Anger camera LS. The second method is more simple and fast when compared with LS plus radioguided surgery. The Imaging Probe (IP) is a portable, hand held, high-resolution mini γ-camera studied by our group since 1998. Initial studies on sentinel node biopsy were carried out by us with IP on small series of patients to validate and to demonstrate the effectiveness and usefulness of IP against conventional probes. The aim of the present study is to show that surgeon removes the mammary sentinel node quicker and safer when using IP and conventional γ-probe together than conventional probe only. The results of our study not only show that our device makes quicker and safer SN biopsy, but also that the number of detected nodes is larger with our method than with conventional diagnostic and surgical techniques.

High-resolution (HR) gamma-ray detector 99m Tc Bombesin (99m TcBN) and 99m Tc sestamibi (99m TcSM), have been used to drive Mammotome biopsy after fusion of scintigraphic with digital X-ray images. We studied eight patients with class V microcalcifications. An HR detector with spatial resolution of 3 mm was matched with Mammotome biopsy system provided with Fisher digital X-ray device: images were fused to use the pointer indifferently on X-ray, scintigraphic and fused images. Fusion between X-ray and HR image has previously been reported. The 12 Mammotome samples/patient were weighted and counted in a well counter. Tumour/bkg (T/B) ratio was measured on HR images as well as on biopsy samples. Axilla was also explored with the portable HR device in order to diagnose node invasion. Conventional histology assessment and immunohystochemical study with anti BN receptor antibody was blindly performed on samples. All the patients studied with 99m TcSM showed T1b cancer, 99m TcBN detected one T1a and two T1b cancers. HR scan of axilla detected node metastases in two patients, both studied with 99m TcBN. All the biopsies showed cancer on at least one of the 12 samples. Histology found node metastases in three patients: the two 99m TcBN positive and one studied with 99m TcSM whose axilla was negative at HR scan. Samples showed T/B ratio of 6.6±0.4 for 99m TcSM and 11.3±0.9 for 99m TcBN (p

Aim: Osteomyelitis is a heavy complication of diabetic foot and its diagnosis requires an integrate approach, both for the clinicians and for the specialist imaging. Leukocytes scan (WBCS) plays a key role in the diagnosis of osteomyelitis. It is performed to reduce the number of amputation, to improve wound healing and to reduce the mortality of patients. The suboptimal spatial resolution of Anger cameras (AC) represents a limitation to achieve these goals. Some studies suggested the role of High Resolution Scintigraphy (HRS) in the diagnosis, radioguided surgery and biopsy of different diseases. Aim of present study is to verify if WBCS is able to improve the diagnosis of osteomyelitis and to help surgery with the use of an hand held High Resolution Detector (HRD),.Materials and Methods: 10 patients, mean age 64 yrs, with forefoot ulcers, were enrolled. In all patients planar X-ray, MRI and conventional 99mTc-HMPAO-WBCs were performed. 24h after administration of radiolabelled WBC, each patient was studied by HRS with HRD. The hand held HRD showed four inch2 FOV, 2 mm spatial resolution, 18% energy resolution. The patients underwent surgery or bone biopsy using HRS.Results: Three patients showed negative scan with both devices. They showed an ulcer without infection, debridement of lesion was sufficient to obtain healing (Table). Seven patients showed positive scan at AC without bone infection. HRD showed hot spots of radioactivity in the same patients. In four of them, the hot spot was bar-shaped. This bar-shaped radioactivity was considered as sign of osteomyelitis. One patient, with positive WBCs, refused surgery. Two patients, with positive scan and no sign of osteomyelitis at AC as well as at HRD underwent complete curettage of purulent inflammation using HRD during the surgical treatment. Two of the 4 patients showing infection at HRD were treated by amputation of the two distal phalanges of the toe because of osteomyelitis. The other patients underwent to radio-guided bone biopsy. Bone infection was confirmed by culture exam.Conclusions: HRD seems to be able to guide surgical treatment opening a new way in the therapy of infected foot. It is possible to assess if surgical removal of purulent inflammation is complete and to precisely guide biopsy or removal of the bone with osteomyelitis.

Bombesin (BN) like peptides modulate some functions of central nervous system (CNS) such as feeding and sleep awake cycle. Other roles, including modulation of psychiatric disorders, have been hypothesised by some researchers. A CNS map of bombesin receptors ( BNR) would help understanding the complex cerebral functions of BN like peptides, but this is not available. 99mTc labelled BN-like peptide scan of CNS is the ideal method to obtain the above map. Our group previously reported synthesis, 99mTc labelling and usefulness for cancer diagnosis of BN-like peptides. We have also developed High Resolution (HR) gamma cameras: HR imaging is mandatory to study CNS of small animals. Methods: We performed HR Planar and SPECT images of rat brain with A) pertechnetate and 99mTc HMPAO to make comparison with labelled BN and B) a 99mTc BN- like peptide. Study A was performed on 3 , study B on 5 rats. Images were acquired under mild anaesthesia with a 2mm space resolution, high sensitivity, 25 cm2 FOV Imaging Probe ( Patented, 4 Patents US and EU). Study B was performed with the BN-like peptide 99mTc BN1.1 ( Patented), 37 MBq in the tail vein. HR Images were acquired at 10, 30 and 60 min after injection. Autopsy was performed at 60 min. Brains were removed, chilled, dissected and the per cent of brain dose was calculated for each brain region. Results: Labelling yield of 99mTc BN1.1 was 97± 0.3%. HR images of 99mTc BN1.1 were significantly different from those of pertechnetate and 99mTc HMPAO. 99mTc BN1.1 showed clear, well defined images of fronto-lateral, temporal cortex, cerebellum and brain stems. Hypothalamus, basal ganglia and amygdala were also detected, though with some difficulties. 10, 30 and 60 min images of 99mTc BN1.1 were very similar, confirming the already-reported-by-us very fast uptake of 99mTc BN. Biodistribution after autopsy showed that only 0.035 of the injected dose is taken up by CNS. Of the dose detected in brain, amygdala and hypothalamus took up 10% each, cerebellum 14%, hippocampus 7.5 %, basal ganglia 6.5% and frontal cortex 4.0 %. Comments: We obtained a map of BNR distribution in rat brain. HR camera images of BNR distribution inside rat brain were consistent with biodistribution after autopsy. Though this distribution is much more complex than prevision, it is consistent with known circuits for regulation of feeding and sleep. Cortical uptake is an intriguing finding that deserves further studies.

In human blood, breakdown of gastrin-releasing peptide and other bombesin-related peptides occurs in less than 15 min. This quick enzymatic cleavage might impair the diagnostic use of labelled bombesin (BN). 99mTc-labelled bombesin (99mTc BN1) was injected intravenously and dynamic uptake data were acquired for diagnosing 26 cancers of different origin: 15 breast, 3 prostate, 5 colo-rectal, 1 pancreas, 2 small cell lung cancers and 1 gastrinoma. Background subtracted tumour uptake data were plotted against time and fitted with known mathematical functions. Twenty-three out of 26 cancers showed rapid increase of radioactivity followed by a radioactivity plateau, with some oscillations around the average plateau value. The time to 80% of max activity (T80) was the reference parameter to measure and to compare the uptake speeds. The slowest T80 was 7 min in one T1b breast cancer, gastrinoma reached T80 in 5 min and node-positive prostate cancers in 2 min. N+ breast cancers showed T80 at 3.62 +/- 0.75 min, N- breast cancers at 5.5 +/- 0.88 min (p0.02). When all the tumours were considered, N+ tumours showed T80 at 2.68 +/- 1.03 min and N- cancers at 5.5 +/- 0.82 min. In all the cancer types, the uptake of 99mTc BN was faster than 10 min. This result shows the ability of 99mTc BN to image tumours. The faster uptake by N+ versus N- cancers probably depends on the higher blood flow in N+ cancers.

Molecular electroactive monolayers have been produced from vinylferrocene (VFC) via light-assisted surface anchoring to H-terminated n- and p-Si(100) wafers prepared via wet chemistry, in a controlled atmosphere. The resulting Si–C bound hybrids have been characterized by means of XPS and AFM. Their performance as semiconductor functionalized electrodes and their surface composition have been followed by combining electrochemical and XPS measurements on the same samples, before and after use in an electrochemical cell.

The chemical reactions and diffusion processe at the interference of a metal with oxides and nitrides are a critical issue in the production of metal-dielectric optical filters. The optical properties of these filters depend on the quality of the interfaces between the metal layer and the adjacent dielectric layers. The chemical and physical processes occuring at the silver-dielectric interface are studied by means of ellipsometry and XPS analysis and comprise the subject of the present work.

Physical review / B 104(23), 235137 (2021). doi:10.1103/PhysRevB.104.235137, We investigate electron-phonon coupling (EPC) in the charge density wave (CDW) phase of VSe$_2$ by Raman spectroscopy, angle-resolved photoemission spectroscopy (ARPES), and ab initio calculations. Zone folding induced by the 4��4 in-plane CDW phase promotes the appearance of a Raman peak at ���170cm$^{���1}$. The suppression of ARPES intensity in parts of the Fermi surface is also a result of CDW-induced zone folding and anticrossing of the electron energy bands. The appearance of the new Raman peak is in line with the ARPES observation of a kink feature in the spectral function at the same energy. A self-energy analysis yields an EPC constant of ��=0.3. Our calculations of the EPC are in excellent agreement and reveal that the kink is caused by several optical phonon branches close in energy. Our paper highlights the CDW phase as a means of inducing EPC pathways to optical phonons that directly affect its Raman spectrum., Published by Inst., Woodbury, NY

Introduction Medullary thyroid cancer (MTC) is a rare malignant tumour of the parafollicular C-cells with an unpredictable clinical course and currently suboptimal diagnostic and therapeutic options, in particular in advanced disease. Overexpression of cholecystokinin-2 receptors (CCK2R) represents a promising avenue to diagnostic imaging and targeted therapy, ideally through a theranostic approach. Materials and methods A translational study (GRAN-T-MTC) conducted through a Phase I multicentre clinical trial of the indium-111 labelled CP04 ([111In]In-CP04), a CCK2R-seeking ligand was initiated with the goal of developing a theranostic compound. Patients with proven advanced/metastatic MTC or short calcitonin doubling time were enrolled. A two-step concept was developed through the use of low- and high-peptide mass (10 and 50 μg, respectively) for safety assessment, with the higher peptide mass considered appropriate for therapeutic application. Gelofusine was co-infused in a randomized fashion in the second step for the evaluation of potential reduction of the absorbed dose to the kidneys. Imaging for the purpose of biodistribution, dosimetry evaluation, and diagnostic assessment were performed as well as pre-, peri-, and postprocedural clinical and biochemical assessment. Results Sixteen patients were enrolled. No serious adverse events after application of the compound at both peptide amounts were witnessed; transient tachycardia and flushing were observed in two patients. No changes in biochemistry and clinical status were observed on follow-up. Preliminary dosimetry assessment revealed the highest dose to urinary bladder, followed by the kidneys and stomach wall. The effective dose for 200 MBq of [111In]In-CP04 was estimated at 7±3 mSv and 7±1 mSv for 10 μg and 50 μg CP04, respectively. Administration of Gelofusine reduced the dose to the kidneys by 53%, resulting in the organ absorbed dose of 0.044±0.019 mSv/MBq. Projected absorbed dose to the kidneys with the use of [177Lu]Lu-CP04 was estimated at 0.9±0.4 Gy/7.4 GBq. [111In]In-CP04 scintigraphy was positive in 13 patients (detection rate of 81%) with superior diagnostic performance over conventional imaging. Conclusion In the present study, [111In]In-CP04 was shown to be a safe and effective radiopharmaceutical with promising theranostic characteristics for patients with advanced MTC.