On the crystal forms of NDI-C6: annealing and deposition procedures to access elusive polymorphs

NDI-C6 has been extensively studied for its semiconducting properties and its processability. It is known to have several polymorphs and a high thermal expansion. Here we report the full thermal characterization of NDI-C6 by combining differential scanning calorimetry, variable temperature X-ray powder diffraction, and hot stage microscopy, which revealed two different thermal behaviours depending on the annealing process. The ranking of stability was determined by the temperature and energy involved in the transitions: Form alpha is stable from RT up to 175 degrees C, Form beta is metastable at all temperatures, Form gamma is stable in the range 175-178 degrees C, and Form delta in the range 178-207 degrees C followed by the melt at 207 degrees C. We determined the crystal structure of Form gamma at 54 degrees C from powder. The analysis of the thermal expansion principal axis shows that Form alpha and Form gamma possess negative thermal expansion (X1) and massive positive thermal expansion (X3) which are correlated to the thermal behaviour observed. We were able to isolate pure Form alpha, Form beta, and Form gamma in thin films and we found a new metastable form, called Form epsilon, by spin coating deposition of a toluene solution of NDI-C6 on Si/SiO2 substrates

Left atrial size is a potent predictor of mortality in mitral regurgitation due to flail leaflets results from a large international multicenter study

Background-Left atrium (LA) enlargement is common in organic mitral regurgitation (MR) and is an emerging prognostic indicator. However, outcome implications of LA enlargement have not been analyzed in the context of routine clinical practice and in a multicenter study. Methods and Results-The Mitral Regurgitation International DAtabase (MIDA) registry enrolls patients with organic MR due to flail leaflets, diagnosed in routine clinical practice, in 5 US and European centers. We investigated the relation between LA diameter and mortality under medical treatment and after mitral surgery in 788 patients in sinus rhythm (64±12 years; median LA, 48 [43 to 52] mm). LA diameter was independently associated with survival after diagnosis (hazard ratio, 1.08 [1.04 to 1.12] per 1 mm increment). Compared with patients with LA<55 mm, those with LA â¥55 mm had lower 8-year overall survival (P<0.001). LA â¥55 mm independently predicted overall mortality (hazard ratio, 3.67 [1.95 to 6.88]) and cardiac mortality (hazard ratio, 3.74 [1.72 to 8.13]) under medical treatment. The association of LA â¥55 mm and mortality was consistent in subgroups. Similar excess mortality associated with LA â¥55 mm was observed in asymptomatic and symptomatic patients (P for interaction, 0.77). In patients who underwent mitral surgery, LA â¥55 mm had no impact on postoperative outcome (P<0.20). Mitral surgery was associated with greater survival benefit in patients with LA â¥55 mm compared with LA <55 mm (P for interaction, 0.008). Conclusions-In MR caused by flail leaflets, LA diameter â¥55 mm is associated with increased mortality under medical treatment, independent of the presence of symptoms or left ventricular dysfunction. © 2011 American Heart Association, Inc

The liquidity of dual-listed corporate bonds: empirical evidence from Italian markets

We compute some indicators (zero-trade, turnover ratio, Amihud price impact, and Roll bid-ask spread) to examine the liquidity conditions of corporate bonds traded on the main Italian retail bond markets from January 2010 to June 2013. In order to compare market liquidity for identical securities, our analysis focuses on fragmented bonds, i.e. bonds traded concurrently on two different venues: either DomesticMOT and EuroTLX, or ExtraMOT and EuroTLX. As for bonds traded on DomesticMOT and EuroTLX, the Amihud and the Roll statistics suggest EuroTLX being more liquid. Moreover, irrespective of the trading venue, on average bank bonds are less liquid than bonds issued by non-financial companies, especially from 2011 due to the impact of the sovereign debt crisis. With regard to bonds traded across ExtraMOT and EuroTLX, the latter is characterized by better liquidity conditions, with bank bonds being more liquid than non-financial ones. Furthermore, we find evidence of better liquidity figures for Italian bonds (nationality), structured bonds (complexity), and securities with greater minimum trading size (MTS). We also find that bonds’ features (issuers’ nationality and industry; bonds’ residual maturity, complexity, rating, etc…) affect liquidity differently depending upon the trading venue, thus supporting the view that market microstructure may play a relevant role. Finally, we investigate the effect of fragmentation by comparing the liquidity of dual-listed bank bonds fragmented across DomesticMOT and EuroTLX with otherwise similar bank bonds traded exclusively on DomesticMOT. Italian fragmented bank bonds turn out to be slightly more liquid than similar Italian bonds traded exclusively on DomesticMOT; whereas, the opposite holds for foreign bank bonds. However, overall there is not a clear-cut evidence on the effect of fragmentation on bond liquidity, probably because it is intertwined with bonds’ attributes, such as the issue size (in our sample, higher for the Italian bank bonds)

Prognostic implications of functional mitral regurgitation according to the severity of the underlying chronic heart failure: A long-term outcome study

AimsTo examine the independent prognostic role of functional mitral regurgitation (FMR) and its impact across the severity of chronic heart failure (CHF) in a large population of outpatients with systolic CHF followed at two multidisciplinary clinics.Methods and resultsEchocardiography was performed upon enrolment in 469 CHF patients. Follow-up for death and heart transplant was updated on January 2007. Five-year transplant-free survival was 82.7 in patients with no or Grade I FMR, 64.4 in Grade II, 58.5 in Grade III, and 46.5 in Grade IV (P < 0.0001). There was a strong graded association between FMR and the long-term risk of death and heart transplant, which remained significant after multivariable adjustment (P = 0.0003). The association between FMR and events was strong and independent in patients with less severe symptoms and in those at lower overall risk based on a propensity score analysis, while it was not significant in patients with more advanced CHF or in the high-risk subgroup (P < 0.0001 for interactions).ConclusionThis study clarifies previous apparently discrepant results by demonstrating that FMR is an independent determinant of death and heart transplantation only in less severe CHF and in patients with a lower risk profile. This finding indicates that FMR plays a major role in the early phase of CHF, suggesting that this should be the focus of strategies attempting to reduce it. \uc2\ua9 The Author 2010

The liquidity of dual-listed corporate bonds: empirical evidence from Italian markets

We compute some indicators (zero-trade, turnover ratio, Amihud price impact, and Roll bid-ask spread) to examine the liquidity conditions of corporate bonds traded on the main Italian retail bond markets from January 2010 to June 2013. In order to compare market liquidity for identical securities, our analysis focuses on fragmented bonds, i.e. bonds traded concurrently on two different venues: either DomesticMOT and EuroTLX, or ExtraMOT and EuroTLX. As for bonds traded on DomesticMOT and EuroTLX, the Amihud and the Roll statistics suggest EuroTLX being more liquid. Moreover, irrespective of the trading venue, on average bank bonds are less liquid than bonds issued by non-financial companies, especially from 2011 due to the impact of the sovereign debt crisis. With regard to bonds traded across ExtraMOT and EuroTLX, the latter is characterized by better liquidity conditions, with bank bonds being more liquid than non-financial ones. Furthermore, we find evidence of better liquidity figures for Italian bonds (nationality), structured bonds (complexity), and securities with greater minimum trading size (MTS). We also find that bonds’ features (issuers’ nationality and industry; bonds’ residual maturity, complexity, rating, etc…) affect liquidity differently depending upon the trading venue, thus supporting the view that market microstructure may play a relevant role. Finally, we investigate the effect of fragmentation by comparing the liquidity of dual-listed bank bonds fragmented across DomesticMOT and EuroTLX with otherwise similar bank bonds traded exclusively on DomesticMOT. Italian fragmented bank bonds turn out to be slightly more liquid than similar Italian bonds traded exclusively on DomesticMOT; whereas, the opposite holds for foreign bank bonds. However, overall there is not a clear-cut evidence on the effect of fragmentation on bond liquidity, probably because it is intertwined with bonds’ attributes, such as the issue size (in our sample, higher for the Italian bank bonds)

Tuning direct-written terahertz metadevices with organic mixed ion-electron conductors

In the past decade, organic mixed ion-electron conductors have been successfully adopted in innovative bioelectronic, neuromorphic, and electro-optical technologies, as well as in multiple energy harvesting and printed electronics applications. However, despite the intense research efforts devoted to these materials, organic mixed conductors have not yet found application in electronic/photonic devices operating in key regions of the electromagnetic spectrum, such as the microwave (>5 GHz) and terahertz (0.1-10 THz) ranges. A possible reason for this technological gap is the widespread notion that organic electronic materials are unsuitable for high-frequency applications. In this work, we demonstrate for the first time the utility of high-performance polymer mixed conductors as electro-active tuning layers in reconfigurable terahertz metasurfaces, achieving modulation performances comparable with state-of-the-art inorganic and 2D semiconductors. Through time-domain terahertz spectroscopy, we show that the large conductivity modulations of these polymers, until now probed only at very low frequencies, are effectively preserved in the terahertz range, leading to optimal metadevice reconfigurability. Finally, we leverage the unique processability of organic materials to develop fully direct-written electrically tuneable metasurfaces onto both rigid and flexible substrates, opening new opportunities for the mass-scale realization of flexible and light-weight terahertz optics with unique mechanical characteristics and environmental footprint

Multiregional sequencing of IDH-WT glioblastoma reveals high genetic heterogeneity and a dynamic evolutionary history

Glioblastoma is one of the most common and lethal primary neoplasms of the brain. Patient survival has not improved significantly over the past three decades and the patient median survival is just over one year. Tumor heterogeneity is thought to be a major determinant of therapeutic failure and a major reason for poor overall survival. This work aims to comprehensively define intra- and inter-tumor heterogeneity by mapping the genomic and mutational landscape of multiple areas of three primary IDH wild-type (IDH-WT) glioblastomas. Using whole exome sequencing, we explored how copy number variation, chromosomal and single loci amplifications/deletions, and mutational burden are spatially distributed across nine different tumor regions. The results show that all tumors exhibit a different signature despite the same diagnosis. Above all, a high inter-tumor heterogeneity emerges. The evolutionary dynamics of all identified mutations within each region underline the questionable value of a single biopsy and thus the therapeutic approach for the patient. Multiregional collection and subsequent sequencing are essential to try to address the clinical challenge of precision medicine. Especially in glioblastoma, this approach could provide powerful support to pathologists and oncologists in evaluating the diagnosis and defining the best treatment option

Chitosan gated organic transistors printed on ethyl cellulose as a versatile platform for edible electronics and bioelectronics

Edible electronics is an emerging research field targeting electronic devices that can be safely ingested and directly digested or metabolized by the human body. As such, it paves the way to a whole new family of applications, ranging from ingestible medical devices and biosensors, to smart labelling for food quality monitoring and anti-counterfeiting. Being a newborn research field, many challenges need to be addressed to realize fully edible electronic components. In particular, an extended library of edible electronic materials is required, with suitable electronic properties depending on the target device and compatible with large-area printing processes, to allow scalable and cost-effective manufacturing. In this work, we propose a platform for future low-voltage edible transistors and circuits that comprises an edible chitosan gating medium and inkjet printed inert gold electrodes, compatible with low thermal budget edible substrates, such as ethylcellulose. We report the compatibility of the platform, characterized by critical channel features as low as 10 µm, with different inkjet printed carbon-based semiconductors, including biocompatible polymers present in the picograms range per device. A complementary organic inverter is also demonstrated with the same platform as a proof-of-principle logic gate. The presented results offer a promising approach to future low-voltage edible active circuitry, as well as a testbed for non-toxic printable semiconductors

A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p