Enhanced photogeneration of polaron pairs in neat semicrystalline donor-acceptor copolymer films via direct excitation of interchain aggregates

We investigate the photogeneration of polaron pairs (PPs) in neat films of the semicrystalline donor–acceptor semiconducting copolymer PCPDTBT. Carefully selecting the solution-processing procedures, we obtain films with different amounts of crystallinity and interchain aggregation. We compare the photogeneration of PPs between the films by monitoring their photoinduced absorption in ultrafast pump–probe experiments, selectively exciting nonaggregated or aggregated polymer chains. The direct photoexcitation of interchain π-aggregates results in prompt (<100 fs) charge generation. Compared to the case where nonaggregated chains are excited, we find an 8-fold increase in the prompt PP to singlet-exciton ratio. We also show that highly crystalline lamellar nanostructures not containing π-stacked or any light-absorbing aggregates do not improve the efficiency of PP photogeneration. Our results show that light absorption from interchain aggregates is highly beneficial for charge photogeneration in semiconducting polymers and should be taken into account when optimizing film morphologies for photovoltaic devices

The use of a new automatic device for patients' assessment at Triage in Emergency Department

Objectives: To assess time saving in an Emergency Department arising out of the introduction of automatic devices (Carescape™ V100) to measure vital signs compared to the manual devices. Methods: We performed a prospective, observational study of eligible patients referring to Sant'Andrea Hospital Emergency Department during the entire month of October 2009, randomly assigned into two groups. In the first group of 476 patients vital signs measurements were detected with manual devices, while in the second group of 477 patients with automatic device Carescape™ V100. Results: Data indicated that the comparison of the total time between the two groups gave a significant difference (1993 vs 1518 min, p < 0.001). No differences were found with respect to age, sex and priority codes. Significant differences were also found when comparing the subgroups of the same acuity categories: white codes 4.33 vs 2.27 (min), p < 0.05; green codes 4.28 vs 3.37 (min), p < 0.001; yellow codes 3.92 vs 2.72 (min), p < 0.001. Conclusions: Our data demonstrated a statistical significance between the two groups with a difference of 475 minutes spent in Triage procedures including vital signs measurements. In conclusion time saved by vital signs automatic device could allow ED physicians to make a qualified approach with an earlier diagnosis and a more rapid and effective therapy, possibly improving patients' outcomes. ABSTRACT of data concerning vital signs quality assessment, because we did not compare the two methods in the same patient and we did not correlate Triage priority evaluation with patients' outcomes. In the future further studies should be specifically aimed to address this issue. In conclusion time saved by vital signs automatic device could allow ED physicians to make a qualified approach to patient with an earlier diagnosis and a more rapid and effective therapy, possibly improving patients' outcomes

(Perylene)3-(TCNQF1)2: Yet Another Member in the Series of Perylene–TCNQFx Polymorphic Charge Transfer Crystals

The 3:2 Charge Transfer (CT) co-crystal (Perylene)3(TCNQF1)2 is grown by the Physical Vapor Transport (PVT) method, and characterized structurally and spectroscopically. Infrared analysis of the charge sensitive modes reveals a low degree of charge transfer (less than 0.1) between donor and acceptor molecules. The crystal is isostructural to the other 3:2 CT crystals formed by Perylene with TCNQF2 and TCNQF4, whereas such stoichiometry and packing is not known for the CT crystals with non-fluorinated TCNQ. The analysis of the isostructural family of 3:2 Perylene–TCNQFx (x = 1,2,4) co-crystal put in evidence the role of weak F…HC bonding in stabilizing this type of structure</jats:p

High Circular Polarization of Electroluminescence Achieved via Self-Assembly of a Light-Emitting Chiral Conjugated Polymer into Multidomain Cholesteric Films.

We demonstrate a facile route to obtain high and broad-band circular polarization of electroluminescence in single-layer polymer OLEDs. As a light-emitting material we use a donor-acceptor polyfluorene with enantiomerically pure chiral side-chains. We show that upon thermal annealing the polymer self-assembles into a multidomain cholesteric film. By varying the thickness of the polymer emitting layer, we achieve high levels of circular polarization of electroluminescence (up to 40% excess of right-handed polarization), which are the highest reported for polymer OLEDs not using chiral dopants or alignment layers. Mueller matrix ellipsometry shows strong optical anisotropies in the film, indicating that the circular polarization of luminescence arises mainly after the photon has been generated, through selective scattering and birefringence correlated in the direction of the initial linear polarization of the photon. Our work demonstrates that chirally substituted conjugated polymers can combine photonic and semiconducting properties in advanced optoelectronic devices

Osteoporosis and cardiovascular diseases’ cosegregation: epidemiological features

Life expectancy in Italy is estimated to rise to 77.9 and 84.4 years in next years. Increased life expectancy is associated with a greater frailty of elderly people and an increased prevalence of chronic and degenerative illnesses such as cardiovascular diseases and osteoporosis. The impact of osteoporotic hip fractures in Italy is very similar to that of acute myocardial infarction (AMI), and there is a need for further epidemiological investigations concerning both the pathologies, as well as for a better understanding of possible mechanisms of their cosegregation. Actually, calcium metabolism is involved both in the development of osteoporosis and in the raise of cardiovascular risk. We have reviewed the most recent publications concerning epidemiological trends of both osteoporosis and acute myocardial infarction (AMI), and also the trials addressing cosegregation of these pathologies. According to the publications examined, in the Italian population (both ³ 45 and > 65 years old), the number of hospitalizations following hip fracture and AMI are comparable. Both hip fractures and cardiovascular diseases represent in Italy a serious medical problem and a leading health cost driver, according to what has already been reported for many other Countries in the industrialized world, thus requiring a global clinical approach. Low calcium intake could represent one of the possible pathogenic paths underlining the association between hypertension and osteoporosis. Low calcium serum levels has been proved to enhance PTH and vitamin D3 production, which result in a remarkable lypogenesis performed by adypocites and switch on mechanisms leading to the raise of blood systolic pressure, the development of atherosclerotic plaques and cardiovascular events. Although many trials have suggested that bone mineral density may be included in the list of cardiovascular risk factors, more studies are needed in order to deeply investigate the causal relationships between calcium metabolism and cardiovascular diseases

How intermolecular geometrical disorder affects the molecular doping of donor-acceptor copolymers

Molecular doping of conjugated polymers represents an important strategy for improving organic electronic devices. However, the widely reported low efficiency of doping remains a crucial limitation to obtain high performance. Here we investigate how charge transfer between dopant and donor\u2013acceptor copolymers is affected by the spatial arrangement of the dopant molecule with respect to the copolymer repeat unit. We p-dope a donor\u2013acceptor copolymer and probe its charge-sensitive molecular vibrations in films by infrared spectroscopy. We find that, compared with a related homopolymer, a four times higher dopant/polymer molar ratio is needed to observe signatures of charges. By DFT methods, we simulate the vibrational spectra, moving the dopant along the copolymer backbone and finding that efficient charge transfer occurs only when the dopant is close to the donor moiety. Our results show that the donor\u2013acceptor structure poses an obstacle to efficient doping, with the acceptor moiety being inactive for p-type doping

Improving the Stability and Performance of Perovskite Light-Emitting Diodes by Thermal Annealing Treatment

$\textbf{A perovskite LED with a perovskite film}$ treated under optimum thermal annealing conditions exhibits a significantly enhanced long-term stability with full coverage of the green electroluminescence emission due to the highly uniform morphology of the perovskite film.This study was supported by the Mid-Career Researcher Program (2015R1A2A2A01003263). This work was fi nancially supported by the KIST-UNIST partnership program (1.150091.01/2.150464.01). This work was also supported by the Human Resource Training Program for Regional Innovation and Creativity through the Ministry of Education and National Research Foundation of Korea (NRF-2014H1C1A1073051). We thank the EPSRC (UK) for support

The association of financial difficulties with clinical outcomes in cancer patients: secondary analysis of 16 academic prospective clinical trials conducted in Italy

Background: Cancer may cause financial difficulties, but its impact in countries with public health systems is unknown. We evaluated the association of financial difficulties with clinical outcomes of cancer patients enrolled in academic clinical trials performed within the Italian public health system. Patients and methods: Data were pooled from 16 prospective multicentre trials in lung, breast or ovarian cancer, using the EORTC quality of life (QOL) C30 questionnaire. Question 28 scores financial difficulties related to disease or treatment in four categories from 'not at all' to 'very much'. We defined financial burden (FB) as any financial difficulty reported at baseline questionnaire, and financial toxicity (FT) as score worsening in a subsequent questionnaire. We investigated (i) the association of FB with clinical outcomes (survival, global QOL response [questions 29/30] and severe toxicity), and (ii) the association of FT with survival. Multivariable analyses were performed using logistic regression models or the Cox model adjusting for trial, gender, age, region and period of enrolment, baseline global QOL and, where appropriate, FB and global QOL response. Results are reported as odds ratio (OR) or hazard ratio (HR) with 95% confidence intervals (CI). Results: At baseline 26% of the 3670 study patients reported FB, significantly correlated with worse baseline global QOL. FB was not associated with risks of death (HR 0.94, 95% CI 0.85-1.04, P = 0.23) and severe toxicity (OR 0.90, 95% CI 0.76-1.06, P = 0.19) but was predictive of a higher chance of worse global QOL response (OR 1.35, 95% CI 1.08-1.70, P = 0.009). During treatment, 2735 (74.5%) patients filled in subsequent questionnaires and 616 (22.5%) developed FT that was significantly associated with an increased risk of death (HR 1.20, 95% CI 1.05-1.37, P = 0.007). Several sensitivity analyses confirmed these findings. Conclusion: Even in a public health system, financial difficulties are associated with relevant cancer patients outcomes like QOL and survival

The HAC Trial (Harmonic for Acute Cholecystitis) Study. Randomized, double-blind, controlled trial of Harmonic(H) versus Monopolar Diathermy (M) for laparoscopic cholecystectomy (LC) for acute cholecystitis (AC) in adults

<p>Abstract</p> <p>Background</p> <p>In the developmental stage of laparoscopic cholecystectomy (LC) it was considered 'unsafe' or 'technically difficult' to perform laparoscopic cholecystectomy for acute cholecystitis (AC). With increasing experience in laparoscopic surgery, a number of centers have reported on the use of laparoscopic cholecystectomy for acute cholecystitis, suggesting that it is technically feasible but at the expense of a high conversion rate, which can be up to 35 per cent and common bile duct lesions.</p> <p>The HARMONIC SCALPEL(R) (H) is the leading ultrasonic cutting and coagulating surgical device, offering surgeons important benefits including: minimal lateral thermal tissue damage, minimal charring and desiccation.</p> <p>Harmonic Scalpel technology reduces the need for ligatures with simultaneous cutting and coagulation: moreover there is not electricity to or through the patient Harmonic Scalpel has a greater precision near vital structures and it produces minimal smoke with improved visibility in the surgical field.</p> <p>In retrospective series LC performed with H was demonstrated feasible and effective with minimal operating time and blood loss: it was reported also a low conversion rate (3.9%).</p> <p>However there are not prospective randomized controlled trials showing the advantages of H compared to MD (the commonly used electrical scalpel) in LC.</p> <p>Methods/Design</p> <p>Aim of this RCT is to demonstrate that H can decrease the conversion rate compared to MD in LC for AC, without a significant increase of morbidity.</p> <p>The patients will be allocated in two groups: in the first group the patient will be submitted to early LC within 72 hours after the diagnosis with H while in the second group will be submitted to early LC within 72 hours with MD.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: NCT00746850</p