Photoluminescence properties of C60 films deposited on silicon substrate

Photoluminescence (PL) spectra of C-60 films deposited on Si substrates have been measured from 10 to 300 K and as a function of laser excitation intensity. Recombination of self-trapped excitons and their phonon replicas, as well as X-trap-related emissions, are the main features of the PL spectra. The influence of the deposition parameters, namely deposition rate and substrate temperature, on the luminescence efficiency of the C-60 films have been investigated. Low substrate temperature produces a lowering of the PL efficiency, whereas an increase of the deposition rate causes an increase of the X-trap emission

Occurrence of grapevine virus A (GVA) and other closteroviruses in Tunisian grapevines affected by leafroll disease

Vorkommen von Grapevine-Virus A (GVA) und anderen Closteroviren in blattrollkranken tunesischen RebenReben, die aus den Hauptweinbaugebieten Tunesiens stammten, wurden auf die Anwesenheit von Closteroviren hin überprüft. Während in keiner der symptomfreien Reben Viruspartikel entdeckt wurden, enthielten alle Reben mit Blattrollsymptomen - außer zweien - Closteroviruspartikel, die durch IEM (immune electron microscopy) in konzentrierten Blattextrakten oder unmittelbar in Rohsaft durch ISEM (immunosorbent electron microscopy) identifiziert wurden. Alle vier derzeit bekannten Closteroviren (GClV-1, GClV-2, GClV-3 und GVA) waren, meistens im Gemisch, in Reben mit Blattrollsymptomen vorhanden. GClV-3 und GVA wurden in 77 bzw. 50 % der geprüften Reben entdeckt. Ein tunesisches Isolat von GVA, das durch Planococcus citri auf krautige Testpflanzen übertragen wurde, unterschied sich in biologischer Hinsicht, aber nicht in den charakteristischen physikalisch-chemischen und serologischen Eigenschaften von zwei italienischen Isolaten desselben Virus

Next-generation sequencing and metagenomic analysis advances plant virus diagnosis and discovery

The advent of next generation sequencing (NGS) technologies dramatically advanced our ability to comprehensively investigate diseases of unknown etiology and expedited the entire process of virus discovery, identification, viral genome sequencing and, subsequently, the development of routine assays for new viral pathogens. Unlike traditional techniques, these novel approaches require no preliminary knowledge of the suspected virus(es). Currently, the RNA-Seq approach has been widely used to identify new viruses in infected plants, by analyzing virus-derived small interfering RNA populations, single- and double-stranded RNA (dsRNA) molecules extracted from infected plants. The method generates sequence in an unbiased fashion, likely allowing to detect all viruses that are present in a sample. We applied the Illumina NGS, coupled with metagenomic analysis, to generate large sequence dataset in different woody crops affected by diseases of unknown origin or infected with uncharacterized viruses or new strains. This approach allowed the identification of five novel viral species and, in addition, the sequencing of the whole genome of several viruses and viroids infecting Citrus spp., Prunus spp., grapes, fig, hazelnut, olive, persimmon and mulberry. Combined analysis of the datasets generated by using either siRNA fractions and dsRNA templates, enhanced the characterization of the whole virus-derived sequences in the infected tissues. Furthermore, profiling small RNAs from virus-infected plants led to a better understanding of host-plant response to virus and viroid infections in perennial plants. A general bioinformatic pipeline and an experimental validation strategy were developed and its application illustrated

Disturbances in groundwater chemical parameters related to seismic and volcanic activity in Kamchatka (Russia)

International audienceStarting from 1992 geochemical data are being collected with a mean sampling frequency of three days in the form of the pH value and of the most common ions and gases in the groundwater in one deep well located in Petropavlovsk, the capital city of Kamchatka (Russia). On 1 January 1996 a strong eruption started from the Karymsky volcano, that is located about 100km far from the well, in the north-northeastern direction. At the same time, a large earthquake (M=6.9) occurred in the Karymsky area. On 5 December 1997 a very large earthquake (M=7.7) occurred offshore, at a distance of 350km from the well and towards the same direction. The analysis of the geochemical data shows clear variations in the raw temporal trends on both cases. For the first event, a clear premonitory phase appeared; for the second one, some pre-seismic variations could be revealed but permanent modifications of the chemistry of the water subsequent to the earthquake are very clear. In both cases the feature of the geochemical variations is consistent with an afflux of new water in the aquifer connected with the well and with an escape of the Carbon dioxide gas from the ground in different directions. A schematic model able to justify such a phenomenology and the connections of the geochemical variations with the previous tectonic activities is proposed

Differential occurrence of S100A7 in breast cancer tissues: A proteomic-based investigation

PURPOSE: The present study reports for the first time a large-scale proteomic screening of the occurrence, subcellular localization and relative quantification of the S100A7 protein among a group of 100 patients, clinically grouped for the diagnosis of infiltrating ductal carcinoma (IDC). EXPERIMENTAL DESIGN: To this purpose, the methods of differential proteomics, Western blotting, and immunohistochemistry were used. RESULTS: The identity of two isoforms of the protein was assessed by mass spectrometry and immunologically confirmed. Moreover, we proved by immunocytochemical applications the exclusive localization of the protein within the neoplastic cells. The correlation of S100A7 expression levels with the collective profile of cancer patients' proteomics predicted functional interactions, distinct for the two isoforms. The S100A7b isoform was significantly correlated with specific protein clusters (calcium binding, signaling and cell motion, heat shock and folding) and intercrossing pathways (antioxidant, metabolic and apoptotic pathways), while the more acidic isoform was correlated with a narrow number of proteins mainly unrelated to the b isoform. CONCLUSIONS AND CLINICAL RELEVANCE: This study is the first proteomic-based report on S100A7 in a large series of IDC patients. The correlation with in silico data may significantly contribute the knowledge of possible pathways for S100A7, providing novel insights into the mechanism of action of this protein. We suggest that each S100A7 isoform is involved in critical phases of the breast cancer growth and progression, probably through interaction with different partner proteins

A possible preseismic anomaly in the ground wave of a radio broadcasting (216 kHz) during July-August 1998 (Italy)

International audienceOn February 1996, a receiver able to measure the electric field strength of LF radio broadcastings, with a sampling frequency of ten minutes, was put into operation in a site (AS) located in central Italy. One of the broadcasting stations selected is MCO (f=216 kHz), located in southeast France, 518 km far from the receiver. The MCO data collected since February 1996 up to September 2004 were examined and, at first, the night time data and the day time data (in winter and summer) were separated. Then, the wavelet analysis on the night and day time data was applied. The main result of the analysis was the appearance of a very clear anomaly during summer (July?August) 1998, at day time and at night time. The anomaly is a strong exaltation of the signal components with period in the 25?40 days range. Theoretical calculations of electric field strength were made and the only way to justify this anomaly seems to be the occurrence of an increase of the ground wave propagation mode of the radio signal. Such an increase could have been produced by an increase of the ground conductivity and by modifications of some parameter of the troposphere, mainly the refractive index. On 15 August 1998 a seismic sequence started with 17 earthquakes (M=2.2?4.6) on the Reatini mountains, a seismogenic zone located 30 km far from the AS receiver along the path MCO-AS. In this paper, the possibility that the previous radio anomaly can be a precursor of this seismic sequence is proposed. </p

Inferior Alveolar Canal Automatic Detection with Deep Learning CNNs on CBCTs: Development of a Novel Model and Release of Open-Source Dataset and Algorithm

Featured Application Convolutional neural networks can accurately identify the Inferior Alveolar Canal, rapidly generating precise 3D data. The datasets and source code used in this paper are publicly available, allowing the reproducibility of the experiments performed. Introduction: The need of accurate three-dimensional data of anatomical structures is increasing in the surgical field. The development of convolutional neural networks (CNNs) has been helping to fill this gap by trying to provide efficient tools to clinicians. Nonetheless, the lack of a fully accessible datasets and open-source algorithms is slowing the improvements in this field. In this paper, we focus on the fully automatic segmentation of the Inferior Alveolar Canal (IAC), which is of immense interest in the dental and maxillo-facial surgeries. Conventionally, only a bidimensional annotation of the IAC is used in common clinical practice. A reliable convolutional neural network (CNNs) might be timesaving in daily practice and improve the quality of assistance. Materials and methods: Cone Beam Computed Tomography (CBCT) volumes obtained from a single radiological center using the same machine were gathered and annotated. The course of the IAC was annotated on the CBCT volumes. A secondary dataset with sparse annotations and a primary dataset with both dense and sparse annotations were generated. Three separate experiments were conducted in order to evaluate the CNN. The IoU and Dice scores of every experiment were recorded as the primary endpoint, while the time needed to achieve the annotation was assessed as the secondary end-point. Results: A total of 347 CBCT volumes were collected, then divided into primary and secondary datasets. Among the three experiments, an IoU score of 0.64 and a Dice score of 0.79 were obtained thanks to the pre-training of the CNN on the secondary dataset and the creation of a novel deep label propagation model, followed by proper training on the primary dataset. To the best of our knowledge, these results are the best ever published in the segmentation of the IAC. The datasets is publicly available and algorithm is published as open-source software. On average, the CNN could produce a 3D annotation of the IAC in 6.33 s, compared to 87.3 s needed by the radiology technician to produce a bidimensional annotation. Conclusions: To resume, the following achievements have been reached. A new state of the art in terms of Dice score was achieved, overcoming the threshold commonly considered of 0.75 for the use in clinical practice. The CNN could fully automatically produce accurate three-dimensional segmentation of the IAC in a rapid setting, compared to the bidimensional annotations commonly used in the clinical practice and generated in a time-consuming manner. We introduced our innovative deep label propagation method to optimize the performance of the CNN in the segmentation of the IAC. For the first time in this field, the datasets and the source codes used were publicly released, granting reproducibility of the experiments and helping in the improvement of IAC segmentation

Substantia Nigra Volumetry with 3-T MRI in De Novo and Advanced Parkinson Disease

Background: Magnetization transfer–prepared T1-weighted MRI can depict a hyperintense subregion of the substantia nigra involved in the degeneration process of Parkinson disease. / Purpose: To evaluate quantitative measurement of substantia nigra volume by using MRI to support clinical diagnosis and staging of Parkinson disease. / Materials and Methods: In this prospective study, a high-spatial-resolution magnetization transfer–prepared T1-weighted volumetric sequence was performed with a 3-T MRI machine between January 2014 and October 2015 for participants with de novo Parkinson disease, advanced Parkinson disease, and healthy control participants. A reproducible semiautomatic quantification analysis method that entailed mesencephalic intensity as an internal reference was used for hyperintense substantia nigra volumetry normalized to intracranial volume. A general linear model with age and sex as covariates was used to compare the three groups. / Results: Eighty participants were evaluated: 20 healthy control participants (mean age ± standard deviation, 56 years ± 11; 11 women), 29 participants with de novo Parkinson disease (64 years ± 10; 19 men), and 31 participants with advanced Parkinson disease (60 years ± 9; 16 women). Volumetric measurement of hyperintense substantia nigra from magnetization transfer–prepared T1-weighted MRI helped differentiate healthy control participants from participants with advanced Parkinson disease (mean difference for ipsilateral side, 64 mm3 ± 14, P < .001; mean difference for contralateral side, 109 mm3 ± 14, P < .001) and helped distinguish healthy control participants from participants with de novo Parkinson disease (mean difference for ipsilateral side, 45 mm3 ± 15, P < .01; mean difference for contralateral side, 66 mm3 ± 15, P < .001) and participants with de novo Parkinson disease from those with advanced Parkinson disease (mean difference for ipsilateral side, 20 mm3 ± 13, P = .40; mean difference for contralateral side, 43 mm3 ± 13, P = .004). / Conclusion: Magnetization transfer–prepared T1-weighted MRI volumetry of the substantia nigra helped differentiate the stages of Parkinson disease