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Titanium nitride (TiN) has recently gained considerable interest because of its remarkable plasmonic properties and for its strong electron–phonon (e–ph) coupling, leading to extremely fast (<100 fs) electron‐lattice cooling. Here, the generation of coherent phonons in TiN films is reported, along with their real‐time detection by means of broadband transient reflection spectroscopy with sub‐15‐fs temporal resolution. The measurements show damped oscillations, superimposed to excited state electronic decay. A coherent vibrational mode is revealed, with ≈10 THz frequency ascribed to defect‐activated normal modes, consistent with spontaneous Raman scattering data, and a dephasing time of ≈250 fs. Two π‐phase flips are also observed located at photon energies corresponding to interband optical transitions (at 3.2 and 2.5 eV), ascribed to selective coupling of the vibrational mode to these transitions; the energy modulation induced by the vibrational coherence is evaluated. It is shown that the displacive excitation of coherent phonons model describes the coherent response in terms of temporal behavior and of spectral amplitude profile. Overall, a comprehensive and detailed analysis of coherent phonons in TiN films, so far undected, is provided and relevant information on TiN photo‐physical properties, potentially useful for its applications, is given. [ABSTRACT FROM AUTHOR]

Ultrafast plasmonics is driving growing interest for the search of novel plasmonic materials, overcoming the main limitations of noble metals. In this framework, titanium nitride (TiN) is brought in the spotlight for its refractory properties combined with an extremely fast electron‐lattice cooling time (<100 fs) compared to gold (≈ 1 ps). Despite the results reported in literature, a clear‐cut explanation of the origin of the ultrafast and giant optical response of TiN‐based materials upon excitation with femtosecond laser pulses is still missing. To address this issue, an original model is introduced, capable of unfolding the modulation of TiN optical properties on a broad bandwidth, starting from the variations of electronic and lattice temperatures following ultrafast photoexcitation. The numerical analysis is validated on ultrafast pump–probe spectroscopy experiments on a simple structure, a TiN film on glass. This approach enables a complete disentanglement of the interband and intraband contributions to the permittivity modulation. Moreover, it is also shown that, varying the synthesis conditions of the TiN film, not only the static, but also the dynamical optical response can be efficiently tuned. These findings pave the way for a breakthrough in the field: the design of TiN‐based ultrafast nanodevices for all‐optical modulation of light. [ABSTRACT FROM AUTHOR]

Plasmonic metasurfaces enable unprecedented manipulation of light by using periodic arrangement of resonant unit cells or nanoantennas. Here, multimetallic metasurfaces made of self‐standing Ni/Au‐Pt nanostructured films are shown to significantly enhance an electrocatalytic oxidation reaction employed in direct alcohol fuel cells. The Ni/Au metasurfaces support photonic and plasmonic modes, which are leveraged for the site‐selective deposition of Pt electrocatalysts within the electromagnetic hot spots, where their reactivity can be strongly increased. The enhanced electrocatalytic activity for the methanol oxidation reaction (MOR) is primarily attributed to electronic effects due to the excitation of hot charge carriers and plasmonic near fields, as supported by electromagnetic simulations and kinetic isotopic experiments. Wavelength‐dependent photoelectrochemical investigations suggest that Ni/Au‐Pt metasurfaces enhances MOR over a broad spectral range and favors different light‐induced reaction mechanisms depending on the selected energy window. [ABSTRACT FROM AUTHOR]

In the present work, we report a preparation strategy for hematite phase‐pure photoanodes consisting of Sn‐doped hematite nanoflakes/hematite thin film bilayer nanostructure (Sn‐HB). This approach is based on a two‐step annealing process of pure iron films deposited on fluorine doped tin oxide (FTO) substrates by advanced magnetron sputtering. While the high density hematite ultrathin nanoflakes (HNs) with detrimental iron oxide layers (Fe3O4 and/or FeO) are generated during the first annealing step at 400 °C for two hours, the second thermal treatment at 800 °C for 15 minutes oxidises all the undesired iron oxide phases to a photoactive hematite layer as well as is providing efficient Sn doping of a drop‐casted SnCl4 in order to increase the conductivity. The optimized Sn‐HB shows an around 11 times higher photocurrent density (0.71 mA cm−2 at 1.23 VRHE) compared with a reference hematite photoanode produced from iron foil under the same conditions. [ABSTRACT FROM AUTHOR]

The photocatalytic activity for H2 production from water, without presence of hole scavengers, of thermally reduced TiO2 nanoparticles (H‐500, H‐700) and neat anatase were followed by in‐situ continuous‐wave light‐induced electron paramagnetic resonance technique (CW‐LEPR), in order to correlate the H2 evolution rates with the electronic fingerprints of the photoexcited systems. Under UV irradiation, photoexcited electrons moved from the deep lattice towards the superficially exposed Ti sites. These photogenerated redox sites mediated (e−+h+) recombination and were the crucial electronic factor affecting catalysis. In the best‐performant system (H‐500), a synergic combination of mobile electrons was observed, which dynamically created diverse types of Ti3+ sites, including interstitial Ti3+, and singly ionized electrons trapped in oxygen vacancies (VO.). The interplay of these species fed successfully surface exposed Ti4+ sites, which became a catalytically active, fast reacting Ti4+⇄Ti3+ state that was key for the H2 evolution process. [ABSTRACT FROM AUTHOR]

Practical‐scale on‐site production of hydrogen peroxide (H2O2) via two‐electron (2e−) oxygen reduction reaction (ORR) relies on efficient, robust, and selective electrocatalysts. Among them, carbon‐based materials are cheap, abundant, durable, and their surface properties can be tuned to favor the 2e− ORR pathways, resulting in higher efficiency and facilitating possible scale‐up towards commercially appealing levels. Here, we demonstrate that the selective installment of carboxyl groups on the surface of N‐doped graphene yielding a material named graphene acid (N‐GA) promotes the catalytic 2e− ORR, achieving a H2O2 faradaic efficiency (FE) as high as 70 % in acidic media (pH=0.96) and a H2O2 productivity in long term bulk electrolysis that could reach 107.8 mmol gcatalyst−1 h−1 under optimized conditions. Extended XPS analysis and density functional theory (DFT) calculations revealed that surface carboxylic acid functional groups play a significant role in achieving the high activity of N‐GA for 2e− ORR. [ABSTRACT FROM AUTHOR]

Abstract: Over the past years, α‐Fe2O3 (hematite) has re‐emerged as a promising photoanode material in photoelectrochemical (PEC) water splitting. In spite of considerable success in obtaining relatively high solar conversion efficiency, the main drawbacks hindering practical application of hematite are its intrinsically hampered charge transport and sluggish oxygen evolution reaction (OER) kinetics on the photoelectrode surface. In the present work, we report a strategy that synergistically addresses both of these critical limitations. Our approach is based on three key features that are applied simultaneously: i) a careful nanostructuring of the hematite photoanode in the form of nanorods, ii) doping of hematite by Sn4+ ions using a controlled gradient, and iii) surface decoration of hematite by a new class of layered double hydroxide (LDH) OER co‐catalysts based on Zn–Co LDH. All three interconnected forms of functionalization result in an extraordinary cathodic shift of the photocurrent onset potential by more than 300 mV and a PEC performance that reaches a photocurrent density of 2.00 mA cm−2 at 1.50 V vs. the reversible hydrogen electrode. [ABSTRACT FROM AUTHOR]

There is a lack of agreement about which routine invitation strategy should be adopted in colorectal cancer screening. We conducted an observational study to assess the impact of three invitation strategies on participation. Invitation records for the years 2005–2009 were evaluated. There were 2,234,276 invitations from 1,230,683 individuals. Among first invitations, participation associated with direct mailing of the faecal occult blood test kits was slightly lower (relative risk, RR 0.985; 95% confidence interval 0.979–0.990) than that of the reference invitation strategy, that is, the distribution of the test kits by pharmacies. In repeated invitations/previous non‐responders, the participation associated with the direct mailing of the test kits was even lower (RR 0.914; 95% confidence interval 0.895–0.933) and this was also the case for the distribution of the test kits by primary care centres (RR 0.983; 95% confidence interval 0.971–0.995). In contrast, in repeated invitations/previous responders, the impact of primary care centres and direct mailing of the test kits was greater than the use of pharmacies, showing only modest RRs: 1.021 (95% confidence interval 1.019‐1.023) and 1.029 (95% confidence interval 1.025–1.033) respectively. The faecal occult blood test mailing strategy modestly increased participation in previous responders. [ABSTRACT FROM AUTHOR]

Three-dimensional printed multi-purpose electrochemical devices for X-ray absorption spectroscopy are presented in this paper. The aim of this work is to show how three-dimensional printing can be a strategy for the creation of electrochemical cells for in situ and in operando experiments by means of synchrotron radiation. As a case study, the description of two cells which have been employed in experiments on photoanodes for photoelectrochemical water splitting are presented. The main advantages of these electrochemical devices are associated with their compactness and with the precision of the three-dimensional printing systems which allows details to be obtained that would otherwise be difficult. Thanks to these systems it was possible to combine synchrotron-based methods with complementary techniques in order to study the mechanism of the photoelectrocatalytic process. [ABSTRACT FROM AUTHOR]

Purpose. To report the accuracy of colposcopically directed biopsy in an internet-based colposcopy quality assurance programme in northern Italy. Methods. A web application was made accessible on the website of the regional Administration. Fifty-nine colposcopists out of the registered 65 logged in, viewed a posted set of 50 digital colpophotographs, classified them for colposcopic impression and need for biopsy, and indicated the most appropriate site for biopsy with a left-button mouse click on the image. Results. Total biopsy failure rate, comprising both nonbiopsy and incorrect selection of biopsy site, was 0.20 in CIN1, 0.11 in CIN2, 0.09 in CIN3, and 0.02 in carcinoma. Errors in the selection of biopsy site were stable between 0.08 and 0.09 in the three grades of CIN while decreasing to 0.01 in carcinoma. In multivariate analysis, the risk of incorrect selection of biopsy site was 1.97 for CIN2, 2.52 for CIN3, and 0.29 for carcinoma versus CIN1. Conclusions. Although total biopsy failure rate decreased regularly with increasing severity of histological diagnosis, the rate of incorrect selection of biopsy site was stable up to CIN3. In multivariate analysis, CIN2 and CIN3 had an independently increased risk of incorrect selection of biopsy site. [ABSTRACT FROM AUTHOR]

Exploiting plasmonic Au nanoparticles to sensitize TiO2 to visible light is a widely employed route to produce efficient photocatalysts. However, a description of the atomic and electronic structure of the semiconductor sites in which charges are injected is still not available. Such a description is of great importance in understanding the underlying physical mechanisms and to improve the design of catalysts with enhanced photoactivity. We investigated changes in the local electronic structure of Ti in pure and N-doped nanostructured TiO2 loaded with Au nanoparticles during continuous selective excitation of the Au localized surface plasmon resonance with X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). Spectral variations strongly support the presence of long-lived charges localized on Ti states at the semiconductor surface, giving rise to new laser-induced low-coordinated Ti sites. [ABSTRACT FROM AUTHOR]

Exploiting plasmonic Au nanoparticles to sensitize TiO2 to visible light is a widely employed route to produce efficient photocatalysts. However, a description of the atomic and electronic structure of the semiconductor sites in which charges are injected is still not available. Such a description is of great importance in understanding the underlying physical mechanisms and to improve the design of catalysts with enhanced photoactivity. We investigated changes in the local electronic structure of Ti in pure and N-doped nanostructured TiO2 loaded with Au nanoparticles during continuous selective excitation of the Au localized surface plasmon resonance with X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). Spectral variations strongly support the presence of long-lived charges localized on Ti states at the semiconductor surface, giving rise to new laser-induced low-coordinated Ti sites. [ABSTRACT FROM AUTHOR]

The article presents a national survey of post-treatment follow-up (FU) practices of screen-detected breast cancer patients in Italy, conducted by the Italian Group for Mammography Screening. Key emphasis of the study include the secondary role of screening radiologists in multidisciplinary teams, the use of intensive protocols in FU services, and exclusion of screen-detected breast cancer patients from Italian screening programs.

Objectives To assess whether maternal blood pressure ( BP) and heart rate ( HR) change significantly in response to pelvic floor muscle training during pregnancy. Design Longitudinal exploratory study with repeated measurements. Sample Twenty-seven nulliparous healthy women of mean age 23.3 years (range 18-36) and mean body mass index 23.4 (range 23.1-29.5). Methods Individual supervised pelvic floor muscle training from gestational week 20 till 36 with assessment of BP and HR at gestational weeks 20, 24, 28, 32 and 36. Main outcome measures Systolic and diastolic BP was measured before and after each training session and HR was monitored during each session. Results Pelvic floor muscle training did not change BP. 77% ( n = 21) of participants exceeded 70% of estimated maximum HR during at least one session. The time for exceeding 70% of estimated maximum HR was between 2.2 and 3.2 % of the total exercise session. Increases in BP and HR from gestational weeks 20 till 36 were within normal limits for pregnant women. Conclusions Pelvic floor muscle training in nulliparous sedentary pregnant women does not increase BP. It significantly increases HR during the exercise sessions, but only for a limited period of time and with no negative long-term effect on BP or HR. [ABSTRACT FROM AUTHOR]

BACKGROUND After the introduction of a mammography screening program, the incidence of late-stage breast cancer is expected to decrease. The objective of the current study was to evaluate variations in the total incidence of breast cancer and in the incidence of breast cancers with a pathologic tumor (pT) classification of pT2 through pT4 after the introduction of mammography screening in 6 Italian administrative regions. METHODS The study area included 700 municipalities, with a total population of 692,824 women ages 55 to 74 years, that were targeted by organized mammography screening between 1991 and 2005. The year screening started at the municipal level (year 1) was identified. The years of screening were numbered from 1 to 8. The ratio of the observed 2-year, age-standardized (Europe) incidence rate to the expected rate (the incidence rate ratio [IRR]) was calculated. Expected rates were estimated assuming that the incidence of breast cancer was stable and was equivalent to that in the last 3 years before year 1. RESULTS The study was based on a total of 14,447 incident breast cancers, including 4036 pT2 through pT4 breast cancers. The total IRR was 1.35 (95% confidence interval, 1.03-1.41) in years 1 and 2, 1.16 (95% confidence interval, 1.10-1.21) in years 3 and 4, 1.14 (95% confidence interval, 1.08-1.20) in years 5 and 6, and 1.14 (95% confidence interval, 1.08-1.21) in years 7 and 8. The IRR for pT2 through pT4 breast cancers was 0.97 (95% confidence interval, 0.90-1.04) in years 1 and 2, 0.81 (95% confidence interval, 0.75-0.88) in years 3 and 4, 0.79 (95% confidence interval, 0.73-0.87) in years 5 and 6, and 0.71 (95% confidence interval, 0.64-0.79) in years 7 and 8. CONCLUSIONS A significant and stable decrease in the incidence of late-stage breast cancer was observed from the third year of screening onward, when the IRR varied between 0.81 and 0.71. Cancer 2013;119:2022-2028. © 2013 American Cancer Society. [ABSTRACT FROM AUTHOR]

The article presents the study "Solar-Powered Plasmon-Enhanced Heterogeneous Catalysis" by A. Naldoni and colleagues published in the "Nanophotonics" journal.