INFN muon tomography demonstrator: past and recent results with an eye to near-future activities.

A short description of the muon tomography demonstrator at the INFN Laboratori Nazionali di Legnaro near Padua, Italy, is given and the principal achievements owing to the data collected at that experimental facility are presented. In particular, the feasibility studies for several applications based on the muon-tomographic technology, within national and European projects, are discussed. The experimental problems and the procedures used to improve the performance are underlined. In addition, new activities and the related detector optimization are illustrated.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.

Relative DNA content in diploid, polyploid, and multiploid species of Paspalum (Poaceae) with relation to reproductive mode and taxonomy.

It is generally accepted that polyploids have downsized basic genomes rather than additive values with respect to their related diploids. Changes in genome size have been reported in correlation with several biological characteristics. About 75 % of around 350 species recognized for Paspalum (Poaceae) are polyploid and most polyploids are apomictic. Multiploid species are common with most of them bearing sexual diploid and apomictic tetraploid or other ploidy levels. DNA content in the embryo and the endosperm was measured by flow cytometry in a seed-by-seed analysis of 47 species including 77 different entities. The relative DNA content of the embryo informed the genome size of the accession while the embryo:endosperm ratio of DNA content revealed its reproductive mode. The genome sizes (2C-value) varied from 0.5 to 6.5 pg and for 29 species were measured for the first time. Flow cytometry provided new information on the reproductive mode for 12 species and one botanical variety and supplied new data for 10 species concerning cytotypes reported for the first time. There was no significant difference between the mean basic genome sizes (1Cx-values) of 32 sexual and 45 apomictic entities. Seventeen entities were diploid and 60 were polyploids with different degrees. There were no clear patterns of changes in 1Cx-values due to polyploidy or reproductive systems, and the existing variations are in concordance with subgeneric taxonomical grouping.

Overview of the negative ion based neutral beam injectors for ITER.

The ITER baseline foresees 2 Heating Neutral Beams (HNB's) based on 1 MeV 40 A D(-) negative ion accelerators, each capable of delivering 16.7 MW of deuterium atoms to the DT plasma, with an optional 3rd HNB injector foreseen as a possible upgrade. In addition, a dedicated diagnostic neutral beam will be injecting ≈22 A of H(0) at 100 keV as the probe beam for charge exchange recombination spectroscopy. The integration of the injectors into the ITER plant is nearly finished necessitating only refinements. A large number of components have passed the final design stage, manufacturing has started, and the essential test beds-for the prototype route chosen-will soon be ready to start.

Non-aggregated Zn(ii)octa(2,6-diphenylphenoxy) phthalocyanine as a hole transporting material for efficient perovskite solar cells.

A non-aggregated Zn(ii)octa(2,6-diphenylphenoxy) phthalocyanine (coded as TT80) has been used as a hole-transporting material for perovskite solar cells. The cells were fabricated under three different configurations by changing the uptake solvent (chlorobenzene or toluene) and incorporating additives (bis(trifluoromethane) sulfonimide lithium salt (LiTFSI) and 4-tert-butylpyridine (TBP). A power conversion efficiency of 6.7% (AM1.5G standard conditions) was achieved for the best cell under optimized configuration.

Branched and bulky substituted ruthenium sensitizers for dye-sensitized solar cells.

We report on the synthesis, and photovoltaic performances of four novel Ru(ii)-bipyridine heteroleptic complexes TT206-209, incorporating branched and bulkier alkyl chains compared to their linear analogues C106 and CYC-B11 previously reported. In both series, we found that dyes containing 2-methyl-hex-2-yl substitution gave better performances than 1,1-dipropylbutyl. The best overall performance over the four dyes was obtained for TT207 (CYC-B11 analogue), which contains 2-methylhex-2-yl type substitution, achieving an overall PCE of 8.5%. Furthermore, the optimization of TT207/DSSCs, with respect to the dye-uptake solvent and electrolyte composition, led to a maximum PCE of 9.1% under AM1.5 G standard conditions.

[Complications of thyroid surgery: cervical thoracic duct injuries]. / Complicanze chirurgiche della tiroidectomia: le lesioni del dotto toracico.

Thoracic duct injury is uncommon in surgery of the neck: relatively more common after laryngeal and esophageal surgery, rare in thyroid surgery. From January 1986 to June 2009 were treated 14 patients with lesions of the cervical thoracic duct undergo surgery for thyroid disease: 4 goitre cervico-mediastinal and 10 total thyroidectomy for cancer, 9 of which have laterocervical left lymphadenectomy. In 2 cases, the intraoperative detection has allowed immediate ligature. In 12 patients a cervical chylous fistula without chilothorax was found: 5 low-flow fistulas and 7 high-flow fistulas. Of the 5 cases of low-flow fistula, 4 were recovered after 1 month of conservative treatment, only 1 patient required surgical correction. The 7 patients with high-flow fistula were undergoing surgery: 4 in the first week post-operative and 3 after a period of more than 30 days of medical therapy. In patients with high-flow fistula prolonged medical treatment does not provide benefit and increase the risk of complications during and after surgery.

Role of magnetic resonance imaging in managing selected women with newly diagnosed breast cancer.

The purpose of this study is evaluation of therapeutic impact of magnetic resonance imaging (MRI) in breast cancer patients that cannot be imaged adequately with traditional radiology: dense breasts, microcalcifications suspicious for carcinoma in situ or discordance between mammography and ultrasound. A review was performed of 493 patients' records: determination of breast MRI effect on clinical management was made for the selected 70 cases by analysing pre-MRI and post-MRI therapeutic plans. Analysis of final pathology was useful to determine if the change in surgical plan prompted by MRI was appropriate. Breast MRI added clinical information in 52.9% of patients that resulted in 44.3% of management changes that were judged as appropriate in 83.9% of cases. Breast MRI provides additional useful information, but causes more extensive surgery (40%) with no proven prognostic benefit. MRI should be considered optional in the clinical staging of breast cancer and performed in selected cases.

[Surgical treatment of well differentiated neuroendocrine tumours of the lung]. / Terapia chirurgica dei tumori neuroendocrini ben differenziati del polmone.

The bronchial tree represents the most frequent site of origin of carcinoids (around 25% of the total). The spectrum of differentiation of lung neuroendocrine tumors ranges from low-malignancy (carcinoids) to highly aggressive forms (small cell lung carcinoma) Diagnostic and therapeutic strategies therefore vary greatly. In well differentiated tumors (carcinoids) signs and symptoms are related to the airways obstruction in central forms, while peripheral forms are mostly discovered accidentally if asymptomatic. Clinical or subclinical paraneoplastic syndromes are associated in a minority of cases. Diagnostic work-up includes CT multislice, bronchial endoscopy and Octreoscan with chest Single Photon Emission Computed Tomography (SPECT). Further contribute may be added by the (68), Ga-DOTA-D-Phe(1)-Tyr(3)-ocreotide (DOTATOC) and 5-hydroxytryptophan (5-HTP) PET-CT, at present available only in a few centres, and by endobronchial ultrasound (EBUS), fluorescence bronchoscopy and virtual bronchoscopy. Surgery is the treatment of choice, while medical therapy is useful to treat the hypersecretion in paraneoplastic syndromes and to control tumor proliferation in metastatic or/and inoperable disease.

[Use of the Dynamic Stent in the palliation of carinal and distal tracheal stenosis]. / Impiego del Dynamic Stent nella palliazione delle lesioni della carena e dell'estremo distale della trachea.

Satisfactory palliation of the lesions involving the carinal region is difficult to achieve because the stenting is conducted in an unsuitable anatomy, in highly symptomatic patients. During the period 1987-2000 we performed 785 operative rigid bronchoscopies in 524 patients, 184 of whom received a respiratory stent. The stenting of the carinal region was carried out in 27 patients with the use of the Frietag Dynamic stent. In this group of patients indication for stenting was as follows:--advanced lung cancer (22);--esophageal cancer invading the lower trachea (1);--severe tracheobronchomalacia (2);--postintubation stenosis of the lower trachea (2). No perioperative mortality was observed. All patients experienced symptomatic improvement. Follow-up ranged from 1 to 60 months: all neoplastic patients died for advanced disease without significant respiratory problems with a median survival of 5.6 months; three patients treated for benign diseases are still alive at 2, 31 and 65 months from stent deployment. No major complications were observed: in two patients the stent was removed after few days due to mucous retention; furthermore we observed symptomatic respiratory infections caused by a residual space between the tracheal wall and the prosthesis in other two patients with severe COPD. Dynamic stent is to be considered the stent of choice for palliation of the carinal region because it is effective and well tolerated with a low complications rate. The main limitations of such prosthesis are the shortness of the right bronchial branch and the size, sometimes inadequate.

Inheritance of apospory in bahiagrass, Paspalum notatum.

Previous studies on the inheritance of aposporous apomixis in bahiagrass showed a wide range of segregation ratios in crosses involving sexual and aposporous apomictic plants. The F1 progenies were classified through a visual progeny test carried out on few F2 plants. The number of sexual F1s highly exceeded the apomictics leading to the conclusion that apomixis was controlled by a few recessive genes. The present study examines the inheritance of apospory in bahiagrass. A sexual plant was self-pollinated and crossed with an aposporous apomictic plant as pollen donor. Backcross and F2 progenies were obtained in several combinations. All self-pollinated sexual plants or sexual x sexual crosses produced progenies free of apospory. All crosses involving a sexual and an apomictic plant produced approximately three times more apospory-free plants than plants with apospory. Bahiagrass is of autotetraploid origin and hence is expected to display tetrasomic inheritance. The most widely accepted genetic model for inheritance of apospory in tropical grasses is a single dominant gene with tetrasomic inheritance. In the present experiments none of the apospory-free F1s segregated for the apospory trait indicating that it is most likely a dominant character. However, the observed results fit better a modified model: tetrasomic inheritance of a single dominant gene with pleiotropic effect and incomplete penetrance. The excess of apospory-free plants in the F1 progeny could be ascribed to some distortion in the segregation pattern due to a pleiotropic lethal effect of the dominant A allele with incomplete penetrance. Alternatively, partial lethality of factors linked to aposporous gene may account for segregation distortion against apospory.

[The role of surgery in the treatment of small cell lung cancer]. / Ruolo della chirurgia nel trattamento del microcitoma polmonare.

Small cell lung cancer (SCLC) is a biologically aggressive tumor with a low long-term survival rate. SCLC is highly responsive to chemotherapy and surgery has a very limited role in its treatment because the disease is usually widely disseminated at the diagnosis. Good results from surgery have been reported in the small subgroup of T1-2 N0 M0 patients. In N1 peripheral SCLC, surgery in combination with other treatments, can obtain fair results. Surgical treatment does not influence the prognosis in SCLC as stage III and IV.

The role of silicone stents in the treatment of cicatricial tracheal stenoses.

OBJECTIVE: Tracheal stenting for cicatricial stenoses is reserved for patients whose lesions are deemed inoperable for local or general reasons. The aim of our study was to verify the long-term results of silicone tracheal stents in such a clinical setting. METHODS: Clinical data of 45 patients treated by tracheal silicone stents, between 1987 and 1999, were reviewed. All patients had highly symptomatic cicatricial stenoses; they were selected for stenting rather than for surgery because of local and general conditions. This series has been divided in two groups according to the purpose of stenting: bridge to surgery or definitive treatment. Follow-up ranged between 12 and 83 months. Twenty-seven patients received a Montgomery T tube (Hood Laboratories, Pembroke, Mass), 16 a Dumon stent (Novatech, Plan de Gras, France), and 2 a Dynamic stent (Rusch, Kernen, Germany). RESULTS: No procedure-related mortality was observed. Nine patients underwent curative resection and reconstruction after a variable stenting period; one had a recurrent stenosis and was treated for palliation with a T tube. Tracheal stenting was performed for palliation as a definitive treatment in 37 patients. Among this group, 11 patients died of unrelated causes at a median of 10 months after the endoscopic treatment. The stent was permanently removed in 10 after a median interval of 32 months (range 9-70 months); in 4 others, symptomatic recurrence of the stenosis was observed within 6 weeks of stent removal. None of the patients successfully decannulated had a completely normal tracheal lumen but all remained asymptomatic because the residual stenosis was mild or well tolerated for concomitant limitation of physical activity. CONCLUSIONS: Long-term treatment with a silicone stent was safe and well tolerated in cicatricial tracheal stenoses. This procedure can be considered as a bridge to curative surgery or as a definitive treatment. The latter, generally performed for palliation, may provide satisfactory therapeutic results in selected patients, even in the presence of severe circumferential stenoses.

Repair of esophageal perforation after treatment for achalasia.

Esophageal perforation after treatment for achalasia is a devastating complication. Successful closure of the perforation and relief of the obstruction from achalasia are paramount. This can be accomplished by careful closure of the mucosa. The mucosal closure is buttressed by a pedicled intercostal muscle carefully sewn to the edges of the muscular defect. This approach deals effectively with the perforation and maintains the myotomy for relief of esophageal obstruction from achalasia.

Long-term safety and tolerance of silicone and self-expandable airway stents: an experimental study.

BACKGROUND: A variety of respiratory stents are currently available, but the ideal airway prosthesis seems far from being recognized. The objective of this study was to verify safety and long-term effect on the bronchial wall of three different types of airway stents. METHODS: Twelve healthy adult sheep were divided in three groups, scheduled to receive: (1) bare self-expandable metallic stents (Gianturco); (2) silicone stents (Dumon); and (3) covered self-expandable synthetic stents (Polyflex). Insertions were performed through a rigid bronchoscope under general anesthesia. Chest roentgenogram was performed 1 and 6 months after surgery, and flexible bronchoscopy after 6 months. Twelve months postoperatively, the animals were killed and a postmortem examination was carried out. RESULTS: All Polyflex stents migrated during the observation period; one late migration was observed in the Dumon group. Microscopic study showed: (1) Gianturco stents: full-thickness perforation of the bronchial wall covered by a thick layer of a chronic inflammatory infiltrate. Infection by Candida at the bottom of some ulcerations; (2) Dumon stents: mild bronchial inflammation (squamous metaplasia, submucosal inflammatory infiltrates; granuloma-like infiltrates). In case of displacement, no significant changes of the previously stented bronchus occurred; and (3) Polyflex stents: no changes of the previously stented bronchi. CONCLUSIONS: Gianturco stents proved unsafe in the long term, owing to the risk of severe airway wall damage. The Polyflex stent is well tolerated but presents a high migration rate. Silicone stents show several limitations but appear to be well tolerated by the host mucosa.

Resection with curative intent after endoscopic treatment of airway obstruction.

BACKGROUND: Endoscopic treatment of malignant central airway obstructions usually is done for palliation. The exact role of such a procedure as preparatory to operation remains controversial. METHODS: From 1987 through 1996, 24 patients at our institution underwent tracheobronchial pulmonary resection after preliminary endoscopic treatment. During the same period, 304 patients underwent 449 operative rigid bronchoscopies for airway obstructions, most involving the use of a neodymium:yttrium-aluminum-garnet laser. The indications for operation were squamous cell carcinoma in 14 patients, bronchial gland tumors in 8 patients, and papillary thyroid cancer infiltrating the trachea in 2 patients. The total resection rate was 9.5% (5% for squamous cell carcinoma, 75% for low-grade malignant bronchial tumors, and 75% for papillary thyroid cancer). The median period between operative rigid bronchoscopy and operation was 18 days. RESULTS: No complications were observed after endoscopic treatment. There were two perioperative deaths (adult respiratory distress syndrome after carinal resection and pulmonary embolism after pneumonectomy) and one major complication (poor postoperative pulmonary function after pneumonectomy). No anastomotic complications were observed in the tracheobronchoplastic procedures. Follow-up was possible in every patient but 1: 6 patients died at a median of 30.5 months after operation (range, 3 to 46 months), 2 patients are alive with disease, and the rest are alive without evidence of disease at a median of 21 months (range, 2 to 61 months). CONCLUSIONS: Most patients who require endoscopic therapy for malignant airway obstructions are not candidates for operative resection. Preliminary endoscopic relief of obstruction can increase operability and improve surgical results in a highly selected group of patients.

In vivo ultrasonic parametric imaging of carotid atherosclerotic plaque by videodensitometric technique.

Extensive experimental and clinical data show that the ultrasonic image conveys information on the biochemical composition of the atherosclerotic plaque, ie, the relative content of lipids (hypoechoic), fibrous tissue (hyperechoic), and calcific deposits (very echogenic with shadowing). A more dishomogeneous echo structure of the plaque is also more often associated with clinically complicated carotid plaques. To date, however, the assessment of plaque density and homogeneity by transcutaneous B-mode imaging remains subjective and qualitative. The aim of this study was to assess whether plaque echodensity and homogeneity might be established on a more objective and quantitative basis by description of the spatial distribution of echo amplitude (referred to as tissue texture) applied to digitized images, obtained with commercially available B-mode transcutaneous imaging systems. A total of 47 B-mode images derived from echotomographic studies in 10 patients were digitized off line. For each region of interest, a set of first-order (mean gray level, standard deviation, skewness, kurtosis: mathematical descriptors of the shape of the frequency distribution of gray-level histogram) and of second-order (entropy, angular moment: mathematical descriptors of the spatial distribution of gray levels within the region of interest) textural parameters were evaluated. The visual, concordant reading by two independent, experienced observers assigned the plaques on the basis of qualitatively assessed echodensity to three groups: "soft" (n = 18), "fibrotic" (n = 20), "calcific" (n = 9). Regarding spatial gray-level distribution, 46 plaques would be separated into "homogenous" (n = 17) and "dishomogeneous" (n = 29). On digitized images, the normalized mean gray level was the most effective first-order textural parameter for distinguishing soft (24.2 +/- 12.4 arbitrary units in a zero to 255 scale) from fibrotic (64.5 +/- 16.4) and calcific plaques (125.3 +/- 24.5), P < 0.01 for all intergroup differences. "Homogeneous" plaques were separated from "heterogeneous" ones on the basis of entropy (5 +/- 1 vs 7.9 +/- 9.7; P < 0.01), whereas the values of angular second moment overlapped (1.542E-3 + 1.334E-3 vs 5.181E-4 +/- 2.5615E-4, P = ns). In conclusion, quantitative texture analysis of ultrasonic images derived from transcutaneous, high-resolution, commercially available B-scan systems is feasible in man and provides a quantitative operator-independent assessment of plaque echodensity and homogeneity.

In vivo radiofrequency-based ultrasonic tissue characterization of the atherosclerotic plaque.

BACKGROUND AND PURPOSE: The ultrasonic image can offer unique information on the composition of atherosclerotic plaque, ie, the relative content of lipids, fibrous tissue, and calcific deposits. To date, however, the echographic assessment of plaque structure is based on a subjective, qualitative evaluation of the bidimensional images. We evaluated the feasibility and accuracy of assessing, in vivo, the acoustic properties of arterial carotid plaques by means of a suitably modified echographic apparatus allowing direct access to the radiofrequency signal. METHODS: In 15 patients undergoing carotid thromboendarterectomy, the ultrasonic findings in 70 discrete sites (within the plaque, n = 54; normal sites, n = 11; or intraluminal thrombi, n = 5) were correlated with the histological analysis (hematoxylin-eosin and Mallory trichrome stains) independently performed on the arterial samples. The pathological examination was carried out at a similar level of the insonation; the sites analyzed within the plaque were chosen because of their uniform echoic characteristics. In each ultrasonic region of interest selected from the echographic image, the integrated amplitude of the rectified radiofrequency signal was measured as the integrated backscatter index. RESULTS: The intimal-medial layer of normal carotid wall (n = 11) exhibited values of -32.5 +/- 9.4 dB. The integrated backscatter index in fatty sites (n = 11, -40.3 +/- 5.4 dB) differed from that of fibrous (n = 12, -23.8 +/- 5.0 dB) and calcified (n = 26, -11.5 +/- 5.2 dB, P < .01 for all intergroup differences) sites. Intraluminal thrombotic sites (n = 5, -42 +/- 5.1 dB, P < .01) differed from fibrous and calcified subsets (P < .01) but overlapped (P = NS) with fatty sites. Histological sampling also showed two sites of intraplaque hemorrhage that exhibited very low backscatter values (-53 and -58 dB) and three fibrofatty sites showing backscatter values (-28, -28, and -32 dB) intermediate between the fibrous and the fatty subsets. CONCLUSIONS: Quantitative analysis of integrated backscatter of the arterial wall is feasible in humans and provides an operator-independent assessment of plaque echoic structure. In particular, integrated backscatter is effective in distinguishing lipidic, fibrotic, and calcific components in human atherosclerotic plaques.