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The anisotropy in semiconductor nanoplatelets (NPLs) is reflected in the anisotropy of their crystal structure and organic ligand shell, which can be used for creating new semiconductor heterostructures. This work demonstrates the synthesis of core/shell NPLs containing zero-dimensional (0D) CdxHg1−xSe domains embedded in CdSe NPLs via cation exchange. The strategy is based on the different accessibility of definite regions of the NPLs for incoming cations upon time-limited reaction conditions. The obtained heterostructures were successfully overcoated with a CdyZn1−yS shell preserving their two-dimensional (2D) morphology. The NPLs exhibit bright photoluminescence in the range of 700-1100 nm with quantum yields up to 55%, thus making them a prospective material for light-emitting applications in the near-infrared spectral range.

The Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) has been available in English since 2008. As part of this process, the MDS-UPDRS organizing team developed guidelines for development of official non- English translations. We present here the formal process for completing officially approved non-English versions of the MDS-UPDRS and specifically focus on the first of these versions in Italian. The MDS-UPDRS was translated into Italian and tested in 377 native-Italian speaking PD patients. Confirmatory and exploratory factor analyses determined whether the factor structure for the English- language MDS-UPDRS could be confirmed in data col- lected using the Italian translation. To be designated an 'Official MDS translation,' the Comparative Fit Index (CFI) had to be C0.90 relative to the English-language version. For all four parts of the Italian MDS-UPDRS, the CFI, in comparison with the English-language data, was C0.94. Exploratory factor analyses revealed some differ- ences between the two datasets, however these differences were considered to be within an acceptable range. The Italian version of the MDS-UPDRS reaches the criterion to be designated as an Official Translation and is now avail- able for use. This protocol will serve as outline for further validation of this in multiple languages.

Cognitive impairment (CI) is a frequent feature associated with both early and advanced stages of Parkinson's disease (PD). An evaluation of cognitive functions is relevant to identify those parkinsonians at risk of developing dementia. In the present study, the Italian version of Parkinson's Disease-Cognitive Rating Scale (PD-CRS) assessing fronto-subcortical and cortical cognitive functions in PD was validated in 387 parkinsonians and was used to test the empirical validity of the item 1.1 (cognitive impairment) of the Italian version of MDS-UPDRS as screening tool for CI in PD. PD-CRS was free from floor and ceiling effect. The mean PD-CRS score was 76.1 (mean cortical score, 24.5 ± 4.6; mean subcortical score, 51.5 ± 17.5). The internal consistency was satisfactory (α = 0.89); corrected item-total correlation was 0.570 (naming) to 0.696 (working memory). The correlation between PD-CRS and part I-IV of MDS-UPDRS was weak. The low agreement between classification of PD sample into patients with mild cognitive impairment (PD-MCI), dementia (PD-D) and normal cognition (PD-NC) according to scores of item 1.1 and classification according to cutoff scores of PD-CRS for PD-MCI, PD-D and PD-NC indicated a poor empirical validity of item 1.1 of MDS-UPDRS as cognitive screening tool for CI in PD (Κ = 0.114; weighted Κ = 0.17; SE of Κ = 0.038; 95 % confidence interval from 0.040 to 0.1895). The Italian version of PD-CRS is an easy, consistent and valid tool for assessment of the cognitive cortical and subcortical impairments in PD. © 2013 Springer-Verlag.

Resonance Raman (RR) spectroscopy is used to investigate the effect of β-cyclodextrin encapsulation on the structural and photophysical properties of poly(4,4′-diphenylenevinylene). We especially focus on the thermal stability of the polymer. We find that within the range of 10-55 C the uninsulated polymer exhibits decreased Raman intensity in all the vibrational bands with temperature, along with changes in the relative intensity of the C-C inter-ring stretch mode at 1270 cm-1 with respect to the ring C-H in-plane symmetric bend at 1187 cm-1, which provides evidence for conformational changes as a function of temperature. No changes are observed in the intensity of the in-phase CH out-of-plane wag of the vinylene group at 968 cm-1. Therefore, the conformational changes involve mainly dihedral angle modification between the adjacent phenyl rings toward planarization, and little or no change in the planarity of the trans-vinylene group. The decrease of the optical absorption at 55 C with respect to that at room temperature and the appearance of a new absorption band at lower energies explain the decrease in the RR intensities and the wavelength dependence of the relative intensities of the Raman band. We note that the conformational change into a more planar geometry, which affects a significant portion of the polymer population, is irreversible and consistent with thermally induced aggregation. Such a planarization is unexpected in view of the usually observed thermochromic behavior of conjugated polymers, which leads to an increase of the energy gap for increasing temperature, as the average dihedral angles are increased due to excitation of a larger number of vibrational modes. Interestingly, the higher threading ratio polymers are resistant to any conformational changes within this temperature range, as reflected by their unchanged RR spectra, due to the rotaxane's ability to suppress intermolecular interactions and aggregation. Interestingly, the conformation of the uninsulated polymer at room temperature appears to be the same as that in the threaded analogues, which suggests that the cyclodextrin cavity hosts the polymer without physically interacting with it. © 2013 American Chemical Society. 117 18 5737 5747 Cited By :7

BKG: Our group has built several prototypes of imaging probe (IP); IP is a small field of view (FOV), High resolution (HR) hand held gamma camera. All the prototypes we have built were used in radioguided surgery, giving noticeable experience to our team. Present IP shows 4 inch2 FOV, 2mm spatial resolution and can be handled by a single operator. AIM: To verify with a multicenter study if our last prototype of IP shows advantages on current lymphoscyntigraphy ( LYS) in detecting sentinel node (SN) in breast cancer (BC). Methods: (A) device: 4inch2 FOV, 2x2x5 mm CsI crystals coupled with position sensitive Photo- multiplier (PSPMT) and integrated with tungsten blade, square hole collimator. very fast home made electronics. IP provides on line images on a sterilizable computer screen. IP is battery operated for wireless use in operator hall. Five US and EU patents cover this IP ( B) Patients: 140 patients with T1 BC, who underwent Anger camera LYS after 99mTc nanocollTM intra-dermal injection, were divided in two age, body mass index, cancer size matched groups of 70 pts each: series A (SA) and series B (SB). During operation SN was detected with a common Gamma Probe (GP) in SA, with IP in SB. A sterile 57Co source signalled the node position to the surgeons. Surgeons removed radioactive nodes without exceeding four nodes. Results: 96 SN were taken off in SA, 124 in SB ( P

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.

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.

Simultaneously achieving both broad absorption and sharp emission in the near-infrared (NIR) is challenging. Coupling of an efficient absorber such as lead halide perovskites to lanthanide emissive species is a promising way to meet the demands for visible to NIR spectral conversion. However, lead based perovskite sensitizers suffer from relatively narrow absorption in the visible range, poor stability, and toxicity. Herein, we introduce a downshifting configuration based on lead-free cesium manganese bromide nanocrystals acting as broad visible absorbers coupled to sharp emission in the NIR-I and NIR-II spectral regions. To achieve this, we synthesized CsMnBr3 and Cs3MnBr5 nanocrystals and attempted to dope them with a series of lanthanides, achieving success only with CsMnBr3. The correlation of the lanthanide emission to the CsMnBr3 visible absorption was confirmed with steady-state excitation spectra and time-resolved photoluminescence measurements, whereas the mechanism of downconversion from the CsMnBr3 matrix to the lanthanides was understood by density functional theory (DFT) calculations. This study shows that lead-free metal halides with an appropriate phase are an effective sensitizer for lanthanides and a route to efficient downshifting applications.

Novel techniques such as mmWave transmission and massive MIMO have proven to present many attractive features able to support high data demand for 5G NR technologies. Towards the standardization of 5G networks, channel modeling has become an important step in order to test the reliability of theoretical studies. In this paper, we study the performance of a 5G network at mmWave range for the downlink. We consider a single trisectorized base station equipped with planar arrays, and we model users as a spatial Poisson process in a hexagonal grid. We adopt the latest 3GPP channel model described in TR 38.901 and we provide a thorough description and step-by-step tutorial of it along with our customizations and MATLAB scripts for channel generation in the presented scenario. Moreover, we evaluate the performance of Multi-User Multi-Layer MIMO techniques, such as Signal-to-Leakage-plus-Noise Ratio (SLNR) precoding and MMSE combined with different system configurations by means of achievable per-user rate.

We report the synthesis of colloidal CsPbX3-Pb4S3Br2 (X=Cl, Br, I) nanocrystal heterostructures, providing an example of a sharp and atomically resolved epitaxial interface between a metal halide perovskite and a non-perovskite lattice. The CsPbBr3-Pb4S3Br2 nanocrystals are prepared by a two-step direct synthesis, using pre-formed sub-nm CsPbBr3 clusters. Density functional theory calculations indicate the creation of a quasi-type II alignment at the heterointerface, as well as the formation of localized trap states, respectively promoting ultrafast separation of photogenerated excitons and carrier trapping, as confirmed by spectroscopic experiments. Post-synthesis reaction with either Cl- or I- ions delivers the corresponding CsPbCl3-Pb4S3Br2 and CsPbI3-Pb4S3Br2 heterostructures, thus enabling anion exchange only in the perovskite domain. An increased structural rigidity is conferred to the perovskite lattice when it is interfaced with the chalcohalide lattice. This is attested by the improved stability of the metastable g phase (or “black” phase) of CsPbI3 in the CsPbI3-Pb4S3Br2 heterostructure.

Background: Neuroinvasive properties of SARS-CoV-2 have allowed the hypothesis of several pathogenic mechanisms related to acute and chronic neurological sequelae. However, neuropathological correlates have been poorly systematically investigated, being retrieved from reports of single case or limited case series still. Methods: A PubMed search was carried out to review all publications on autopsy in subjects with “COronaVIrus Disease-19” (COVID-19). Among them, we focused on histological findings of the brain, which were compared with those from the authors’ autoptic studies performed in some COVID-19 patients. Results: Only seven studies reported histological evidence of brain pathology in patients deceased for COVID-19, including three with reverse transcription–quantitative polymerase chain reaction evidence of viral infection. All these studies, in line with our experience, showed vascular-related and infection-related secondary inflammatory tissue damage due to an abnormal immune response. It is still unclear, however, whether these findings are the effect of a direct viral pathology or rather reflect a non-specific consequence of cardiovascular and pulmonary disease on the brain. Conclusions: Notwithstanding the limited evidence available and the heterogeneity of the studies, we provide a preliminary description of the relationship between SARS-CoV-2 and brain sequelae. Systematic autoptic investigations are needed for accurate detection and adequate management of these patients.

In this paper, we study the performance of a 5G base station working in the mmWave range equipped with a cylindrical array. Conventional and Capon beamforming techniques are taken into account. We consider both isotropic and directive antenna elements and we evaluate the trade-off between antennas per ring and number of rings with fixed number of total antennas. Results are provided in terms of average achievable per-user rate with different system configurations, such as of network loading. We show that in the presented scenario, where users are randomly deployed in a hexagonal plane, the best performance occurs when the cylindrical array degenerates in a circular array.