Efficient photosynthesis of carbon monoxide from CO2 using perovskite photovoltaics

Artificial photosynthesis, mimicking nature in its efforts to store solar energy, has received considerable attention from the research community. Most of these attempts target the production of H2 as a fuel and our group recently demonstrated solar-to-hydrogen conversion at 12.3% efficiency. Here, in an effort to take this approach closer to real photosynthesis, which is based on the conversion of CO2, we demonstrate the efficient reduction of CO2 to carbon monoxide driven solely by simulated sunlight using water as the electron source. Employing series-connected perovskite photovoltaics and high-performance catalyst electrodes, we reach a solar-to-CO efficiency exceeding 6.5%, which represents a new benchmark in sunlight-driven CO2 conversion. Considering hydrogen as a secondary product, an efficiency exceeding 7% is observed. Furthermore, this study represents one of the first demonstrations of extended, stable operation of perovskite photovoltaics, whose large open-circuit voltage is shown to be particularly suited for this process

Toolkit for simulated commissioning of storage-ring light sources and application to the advanced light source upgrade accumulator

We present a new accelerator toolbox (AT)-based toolkit for simulating the commissioning of light-source storage rings. The toolkit provides a framework for supporting high-level scripts to represent with realism the various procedures (e.g., orbit and optics correction, beam-based alignment, etc.) encountered during commissioning and is designed to mirror as closely as possible the reality as seen from the control room. Emphasis is placed on the inclusion of a comprehensive set of error sources and faithful modeling of beam diagnostics. The toolkit capabilities are demonstrated in an application to the recent design and commissioning studies of the Advanced Light Source Upgrade (ALS-U) Accumulator Ring, a short-time successful commissioning of which will be critical to the overall ALS-U project success

Assessment of the radiological impact of a decommissioning nuclear power plant in Italy

The assessment of the radiological impact of a decommissioning Nuclear Power Plant is presented here through the results of an environmental monitoring survey carried out in the area surrounding the Garigliano Power Plant. The levels of radioactivity in soil, water, air and other environmental matrices are shown, in which {\alpha}, {\beta} and {\gamma} activity and {\gamma} equivalent dose rate are measured. Radioactivity levels of the samples from the Garigliano area are analyzed and then compared to those from a control zone situated more than 100 km away. Moreover, a comparison is made with a previous survey held in 2001. The analyses and comparisons show no significant alteration in the radiological characteristics of the area surroundings the plant, with an overall radioactivity depending mainly from the global fallout and natural sources.Comment: 13 pages, 6 figures, 2 table

Assessment of the radiological impact of a decommissioning nuclear power plant in Italy

The assessment of the radiological impact of a decommissioning Nuclear Power Plant is presented here through the results of an environmental monitoring survey carried out in the area surrounding the Garigliano Power Plant. The levels of radioactivity in soil, water, air and other environmental matrices are shown, in which {\alpha}, {\beta} and {\gamma} activity and {\gamma} equivalent dose rate are measured. Radioactivity levels of the samples from the Garigliano area are analyzed and then compared to those from a control zone situated more than 100 km away. Moreover, a comparison is made with a previous survey held in 2001. The analyses and comparisons show no significant alteration in the radiological characteristics of the area surroundings the plant, with an overall radioactivity depending mainly from the global fallout and natural sources

Effectiveness of photodynamic therapy and sodium hypochlorite on root canal system infected with Enterococcus faecalis - an in vitro study

Portuguese title: Eficácia da terapia fotodinâmica e do hipoclorito de sódio sobre o sistema de canais radiculares infectado com Enterococcus faecalis - um estudo in vitro Abstract and Keywords also in Portuguese. Journal title in English: Journal of Dental Science.Objective: The purpose of this study was to evaluate, in vitro , the effectiveness of photodynamic therapy and sodium hypochlorite over root canal system infected with Enterococcus faecalis . Methods: The root canals of 45 single-rooted human extracted teeth were enlarged up to a file 60, autoclaved, inoculated with Enterococcus faecalis and incubated for 30 days. The samples were divided into five groups (G1 – n=5; G2-G5 – n=10) according to the protocol of decontamination: G1 (negative control) – no procedure was performed; G2 – distilled water; G3 – photodynamic therapy (PDT); G4 – 2.5% sodium hypochlorite (NaOCl); and G5 – 2.5% NaOCl+PDT. Scanning electron microscopy (SEM) were performed to evaluate the effectiveness of proposed treatments. The assessment was made by images of each third at 5000x magnification for the canal wall and 10000x for the exposed tubule area. The presence of bacteria was scored by position ranks from 1 to 45, where the higher the value, the cleanliness of the sample. Data were subjected to one-way ANOVA followed by post-hoc Tukey test ( α =0.05). Results: Group 4 (2.5% NaOCl) and 5 (2.5% NaOCl + PDT) had the highest mean of position ranks for all thirds of the root canal in the canal wall, which was statistically different from groups 1, 2 and 3 ( p <0.05). Group 3 (PDT), group 4 (2.5% NaOCl) and 5 (2.5% NaOCl+PDT) had the highest mean of position ranks in the exposed tubule area, which was statistically different from groups 1 and 2 ( p <0.05). Conclusion: the association of 2.5% sodium hypochlorite + photodynamic therapy can be considered an effective protocol for the elimination of Enterococcus faecalis. = Objetivo: o propósito deste estudo foi avaliar, in vitro, a eficácia da terapia fotodinâmica e do hipoclorito de sódio sobre o sistema de canais radiculares infectados com Enterococcus faecalis. Metodologia: Os canais radiculares de 45 dentes humanos extraídos unirradiculares foram ampliados até a lima 60, autoclavados, inoculados com Enterococcus faecalis e incubados por 30 dias. As amostras foram divididas em cinco grupos (G1 – n=5; G2-G5 – n=10) de acordo com o protocolo de descontaminação: G1 (controle negativo) – não foi realizado procedimento; G2 – água destilada; G3 – terapia fotodinâmica; G4 – hipoclorito de sódio 2,5%; G5 – hipoclorito de sódio 2,5%+terapia fotodinâmica. Microscopia eletrônica de varredura foi realizada para avaliar a eficácia dos tratamentos propostos. A avaliação foi feita através de imagens de cada terço a 5000x de magnificação nas paredes do canal e 10000x na profundidade dos túbulos dentinários. A presença de bacterias foi determinada por intermédio de rank de posições a partir de 1 até 45, onde quanto maior o valor, maior a limpeza da amostra. Os dados foram submetidos a one-way ANOVA seguido por post-hoc de Tukey (α=0.05). Resultados: Grupo 4 (NaOCl 2,5%) e 5 (NaOCl 2,5%+PDT) obtiveram a maior media de posição de ranks para todos os terços do canal radicular na parede do canal, o que foi estatisticamente diferente dos grupos 1, 2 e 3 (p<0.05). Grupo 3 (PDT), grupo 4 (NaOCl 2,5%) e 5 (NaOCl 2,5%+PDT) obtiveram a maior méida de posição de ranks para todos os terços do canal radicular na profundidade dos túbulos dentinários, o que foi estatisticamente diferente dos grupos 1 e 2 (p<0,05). Conclusão: A associação de hipoclorito de sódio.Matheus Albino Souza, Liviu Steier, Giampiero Rossi-Fedele, Valdir Barth Júnior, Silvia Dias de Oliveira, José Antônio Poli de Figueired

Pego do Diabo (Loures, Portugal): Dating the Emergence of Anatomical Modernity in Westernmost Eurasia

Neandertals and the Middle Paleolithic persisted in the Iberian Peninsula south of the Ebro drainage system for several millennia beyond their assimilation/replacement elsewhere in Europe. As only modern humans are associated with the later stages of the Aurignacian, the duration of this persistence pattern can be assessed via the dating of diagnostic occurrences of such stages

Acute ischaemic hemispheric stroke is associated with impairment of reflex in addition to voluntary cough

Cough function is impaired after stroke; this may be important for protection against chest infection. Reflex cough (RC) intensity indices have not been described after stroke. RC, voluntary cough (VC) and respiratory muscle strength were studied in patients within 2 weeks of hemispheric infarct. The null hypotheses were that patients with cortical hemisphere stroke would show the same results as healthy controls on: 1) objective indices of RC and VC intensity; and 2) respiratory muscle strength tests.Peak cough flow rate (PCFR) and gastric pressure (Pga) were measured during maximum VC and RC. Participants also underwent volitional and nonvolitional respiratory muscle testing. Nonvolitional expiratory muscle strength was assessed by measuring Pga increase after magnetic stimulation over the T10 nerve roots (twitch T10 Pga). Stroke severity was scored using the National Institutes of Health Stroke Scale (NIHSS; maximum = 31).18 patients (mean±SD age 62±15 yrs and NIHSS score 14±8) and 20 controls (56±16 yrs) participated. VC intensity was impaired in patients (PCFR 287±171 versus 497±122 L·min−1) as was VC Pga (98.5±61.6 versus 208.5±61.3 cmH2O; p&lt;0.001 for both). RC PCFR was reduced in patients (204±111 versus 379±110 L·min−1; p&lt;0.001), but RC Pga was not significantly different from that of controls (179.0±78.0 versus 208.0±77.4 cmH2O; p = 0.266). Patients exhibited impaired volitional respiratory muscle tests, but twitch T10 Pga was normal.VC and RC are both impaired in hemispheric stroke patients, despite preserved expiratory muscle strength. Cough coordination is probably cortically modulated and affected by hemispheric stroke

In situ observation of picosecond polaron self-localisation in α-Fe2O3 photoelectrochemical cells

Hematite (α-Fe2O3) is the most studied artificial oxygen-evolving photo-anode and yet its efficiency limitations and their origin remain unknown. A sub-picosecond reorganisation of the hematite structure has been proposed as the mechanism which dictates carrier lifetimes, energetics and the ultimate conversion yields. However, the importance of this reorganisation for actual device performance is unclear. Here we report an in situ observation of charge carrier self-localisation in a hematite device, and demonstrate that this process affects recombination losses in photoelectrochemical cells. We apply an ultrafast, device-based optical-control method to resolve the subpicosecond formation of small polarons and estimate their reorganisation energy to be ~0.5 eV. Coherent oscillations in the photocurrent signals indicate that polaron formation may be coupled to specific phonon modes (<100 cm-1). Our results bring together spectroscopic and device characterisation approaches to reveal new photophysics of broadly-studied hematite devices