358 research outputs found
A Novel Mutation in Lamin A/C Gene: Phenotype and Consequences on the Protein Structure and Flexibility
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Population Saturation in Trivalent Erbium Sensitized by Organic Molecular Antennae
We investigate sensitization efficiency of near-infrared emission and population saturation of trivalent erbium in erbium quincilinolato complexes photoexcited into the absorption band of the organic sensitizer. At low excitation levels, we find high (similar to 80%) sensitization efficiencies. We observe excited state population saturation at inversion threshold under subnanosecond pumping at the level of one injected photoexcitation per complex
Light-Induced Charged and Trap States in Colloidal Nanocrystals Detected by Variable Pulse Rate Photoluminescence Spectroscopy
<p>Intensity instabilities are a common trademark of the photoluminescence of nanoemitters. This general behavior is commonly attributed to random fluctuations of free charges and activation of charge traps reducing the emission yield intermittently. However, the actual physical origin of this phenomenon is actively debated. Here we devise an experiment, variable pulse rate photoluminescence, to control the accumulation of charges and the activation of charge traps. The dynamics of these states is studied, with pulse repetition frequencies from the single-pulse to the megahertz regime, by monitoring photoluminescence spectrograms with picosecond temporal resolution. We find that both photocharging and charge trapping contribute to photoluminescence quenching, and both processes can be reversibly induced by light. Our spectroscopic technique demonstrates that charge accumulation and trap formation are strongly sensitive to the environment, showing different dynamics when nanocrystals are dispersed in solution or deposited as a film.</p>
Genotype of Melatonin Receptor MT1 (MTNR1A) and Puberty in Mediterranean Italian Buffalo
In adult buffaloes, polymorphism of the MT1 receptor gene has shown to influence the reproductive seasonality. The aim of study was to assess whether the polymorphism of the MTNR1A gene may influence puberty in Mediterranean Italian buffalo.
The study was conducted using 50 prepubertal buffalo cows that at the age of 15 months were placed into the group where there was the male. Estrus detection was performed by observing estrous-behaviour and pregnancy checking by palpation per rectum and/or ultrasound between days 40 and 60 post-mating. Also of each animal dates of calving was recorded. From each buffalos a blood sample was collected and used for DNA extraction. PCR analysis was performed using 100-150 ng of DNA to amplify the second exon of the MTNRA1 gene. All PCR products were digested with 2U of enzyme HpaI to highlight the polymorphism at position 82 (characterized by a C to a T substitution) of the MTNR1A gene. Frequency of C and T alleles was respectively 0.42 and 0.58 in the analyzed population which resulted in Hardy Weinberg equilibrium. The genotypic frequency was 28% for genotype C/C, 38% for C/T and 34% for T/T. The registration of reproductive data showed that the first heat is around the age of 20 months and the first calving around 32 months. Our data show that the genotype of the MTNR1A does not influence the onset of reproductive activity in prepubertal buffalo cows
Effects of the diphenyl ether additive in halogen-free processed non-fullerene acceptor organic solar cells
The development of an environmentally friendly fabrication process for non-fullerene acceptor organic solar cells is an essential condition for their commercialization. However, devices fabricated by processing the active layer with green solvents still struggle to reach, in terms of efficiency, the same performance as those fabricated with halogenated solvents. The reason behind this is the non-optimal nanostructure of the active layer obtained with green solvents. Additives in solution have been used to fine-tune the nanostructure and improve the performance of organic solar cells. Therefore, the identification of non-halogenated additives and the study of their effects on the device performance and stability are of primary importance. In this work, we propose the use of diphenyl ether (DPE) as additive, in combination with the non-halogenated solvent o-xylene, to fabricate organic solar cells with a completely halogen-free process. Thanks to the addition of DPE, a best efficiency of 11.7% have been obtained for the system TPD-3F:IT-4F, an increase over 15% with respect to the efficiency of devices fabricated without additive. Remarkably, the stability under illumination of the solar cells is also improved when DPE is used. The addition of DPE has effects on the molecular organization in the active layer, with an enhancement in the donor polymer ordering, showing a higher domain purity. The resulting structure improves the charge carrier collection, leading to a superior short-circuit current and fill factor. Furthermore, a reduction of the non-radiative recombination losses and an improved exciton diffusion, are the results of the superior molecular ordering. With a comprehensive insight of the effects of DPE when used in combination with a non-halogenated solvent, our study provides an approach to make the fabrication of organic solar cell environmentally friendlier and more suitable for large scale production
Tuning the energy transfer in RuddlesdenâPopper perovskites phases through isopropylammonium addition â towards efficient blue emitters
Here we demonstrate blue LEDs with a peak wavelength of 481 nm, with outstanding colour purity of up to 88% (CIE coordinates (0.1092, 0.1738)), an external quantum yield of 5.2% and a luminance of 8260 cd mâ2. These devices are based on quasi-2D PEA2(Cs0.75MA0.25)Pb2Br7, which is cast from solutions containing isopropylammonium (iPAm). iPAm as additive assist in supressing the formation of bulk-like phases, as pointed out by both photophysical and structural characterization. Additionally, the study of the excitation dynamics demonstrates a hindering of the energy transfer to domains of lower energy that generally undermines the performance and emission characteristics of blue-emitting LEDs based on quasi-2D perovskites. The achieved narrow distribution of quantum well sizes and the hindered energy transfer result in a thin film photoluminescence quantum yield exceeding 60%. Our work demonstrates the great potential to tailor the composition and the structure of thin films based on Ruddlesden-Popper phases to boost performance of optoelectronic devices - specifically blue perovskite LEDs
Evidence for preferences of Italian patients for physician attire
BACKGROUND: The relationship between patient and physician is a complex interaction that includes multiple factors. The objective of this study was to explore Italian patients' preferences regarding physician appearance.
METHODS: A questionnaire was developed to survey patients in different medical and surgical settings; each subject was asked to choose one picture of either a male or female physician from a selection of different attires (professional, casual, surgical scrubs, trendy, and careless). Patients were also surveyed about issues such as the presence of a name tag, hair length, trousers on women, amount of makeup, presence of tattoos, and body piercing. Statistical analysis was performed using a Chi-square test.
RESULTS: A total of 765 questionnaires (534 completed from patients waiting for an internal medicine visit and 231 for other subspecialties) were completed. The majority (45%) of patients preferred the gastroenterologist to wear a surgical scrub with a white coat. For the other specialists, patients accepted either scrubs or formal dress under a white coat (P †0.05), with a name tag. Trendy attire was preferred by nine patients (1.1%). The entire sample judged it inappropriate for clinicians to have long hair, visible tattoos, body piercing, and, for women, to wear trousers and use excessive makeup.
CONCLUSION: This is the first study conducted in Italy regarding physician attire. As in other Western countries, Italian patients favor physicians in professional attire with a white coat. Wearing professional dress is part of "etiquette based medicine" and may favorably influence clinician-patient relationships and patient compliance.</br
Presence of Bacillus cereus, Escherichia coli and Enterobacteriaceae in fresh and salted Ricotta cheese: official controls in Sardinia during the period 2009 â 2012.
Results of microbiological official analysis carried out during 2009-2012 for detection of Bacillus cereus, Escherichia coli and Enterobacteriaceae in fresh and salted Ricotta cheese marketed in Sardinia, are re-ported. The aim of this research was to evaluate the presence of contaminants indicators of process hy-giene, and the presence of B. cereus, which while not covered in the EC Regulation 2073/05 for this product, it may represent a risk as a potential producer of toxins harmful to the consumer health. Were analyzed a total of 157 samples according to ISO reference. The results indicate a widespread presence of the three types of microorganisms sought: prevalence of B. cereus 53%, 23% Enterobacteriaceae, E. coli 12%. In conclusion, it is desirable the introduction, in the production process, keeping the cold chain to prevent the risk from B. cereus, and improved hygiene of processing plant, equipment and personnel, to reduce recontamination of the product by the Enterobacteriaceae and E. coli
Optical Frequency Link between Torino and Firenze for remote comparison between Yb and Sr optical clocks
Efficacy of 1998 <i>vs</i> 2006 first-line antiretroviral regimens for HIV infection: an ordinary clinics retrospective investigation
Purpose: The evidence suggesting increased HAART efficacy over time comes from randomized trials or cohort
studies. This retrospective multicenter survey aimed to assess the variation over time in the efficacy and tolerability of first-line HAART regimens in unselected patients treated in ordinary clinical settings.
Methods: Retrospective analysis of data of all patients starting first-line HAART regimens in 1998 and 2006 at adhering centers in the Italian CISAI group.
Results: For the 543 patients included, mean age was 39.1 ± 9.8y in 1998 and 41.0 ± 10.7y in 2006 (p=0.03),
with a similar proportion of males. Baseline mean log10 HIV-RNA was 4.56 ± 0.97 copies/mL in 1998 vs 4.91 ± 0.96
copies/mL in 2006 (p<0.001); baseline mean CD4 T-cell counts were 343 ± 314/mm3 in 1998 vs 244 ± 174/mm3 in
2006 (p<0.001). The following outcomes were significantly improved at 48w in 2006: proportion with undetectable HIV-RNA (86.3% vs 58.0%; p<0.001); mean increase in CD4 T-cells count (252 ± 225 vs 173 ± 246; p<0.001); HAART modification (20.1% vs 29.2%; p=0.02); HAART interruption (7.3% vs 14.6%; p=0.01); proportion reporting optimal adherence (92.2% vs 82.7%, p=0.03). No differences were observed in the prevalence of grade 3-4 WHO toxicities (26.4% vs 26.6%; p=0.9). Multivariate logistic regression showed that being treated in 1998 remained an independent predictor of virological failure after several adjustments, including adherence.
Conclusions: Our data from patients not included in clinical trials or cohort studies provide an additional
line of evidence that the effectiveness of HAART significantly improved in 2006. Treated patients, however, were significantly older and more frequently late HIV presenters in 2006 than in 1998.</br
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