High Photovoltaic Quantum Efficiency in Ultrathin van der Waals Heterostructures

We report experimental measurements for ultrathin (< 15 nm) van der Waals heterostructures exhibiting external quantum efficiencies exceeding 50%, and show that these structures can achieve experimental absorbance > 90%. By coupling electromagnetic simulations and experimental measurements, we show that pn WSe2/MoS2 heterojunctions with vertical carrier collection can have internal photocarrier collection efficiencies exceeding 70%.Comment: ACS Nano, 2017. Manuscript (25 pages, 7 figures) plus supporting information (7 pages, 4 figures

Neoadjuvant therapy for breast cancer

Objective: To evaluate the frequency of neoadjuvant therapy (NT) in women with stage I–III breast cancer in Italy and whether it is influenced by biological characteristics, screening history, and geographic area. Methods: Data from the High Resolution Study conducted in 7 Italian cancer registries were used; they are a representative sample of incident cancers in the study period (2009–2013). Included were 3546 women aged &lt;85 years (groups &lt;50, 50–69, 70–64, and 75+) with stage I–III breast cancer at diagnosis who underwent surgery. Women were classified as receiving NT if they received chemotherapy, target therapy, and/or hormone therapy before the first surgical treatment. Logistic models were built to test the association with biological and contextual variables. Results: Only 8.2% of women (290 cases) underwent NT; the treatment decreases with increasing age (14.5% in age &lt;50 and 2.2% in age 75+), is more frequent in women with negative receptors (14.8%), HER2-positive (15.7%), and triple-negative (15.6%). The multivariable analysis showed the probability of receiving NT is higher in stage III (odds ratio [OR] 3.83; 95% confidence interval [CI] 2.83–5.18), luminal B (OR 1.87; 95% CI 1.27–2.76), triple-negatives (OR 1.88; 95% CI 1.15–3.08), and in symptomatic cancers (OR 1.98; 95% CI 1.13–3.48). Use of NT varied among geographic areas: Reggio Emilia had the highest rates (OR 2.29; 95% CI 1.37–3.82) while Palermo had the lowest (OR 0.41; 95% CI 0.24–0.68). Conclusions: The use of NT in Italy is limited and variable. There are no signs of greater use in hospitals with more advanced care

Behavioural Differences in Sensorimotor Profiles: A Comparison of Preschool-Aged Children with Sensory Processing Disorder and Autism Spectrum Disorders

Sensory Processing Disorders (SPDs) define dysfunctions in modulating, organising, and using information from several sensory channels for regulating motor, behavioural, emotional and attention responses. Although SPD can be identified also as an isolated condition in young children, its presence in Autism Spectrum Disorder (ASD) population is really frequent. The study purpose is to explore the SPD clinical expression and the putative correlation with several behavioural aspects both in children with ASD and in those with isolated SPD. Therefore, 43 preschool-aged children (25 ASD vs. 18 SPD) were recruited, and their parents completed three questionnaires (Developmental Profile-3, Sensory Processing Measure–Preschool, Repetitive Behaviour Scale-Revised) to evaluate behavioural alterations and developmental levels. The main result is that both ASD and SPD groups had significantly sensory-related behavioural symptoms, although ASD children seem to be more impaired in all areas. Several significant correlations were found between sensory processing difficulties and repetitive behaviours, but in the SPD group a specific relationship between Body Awareness and Ritualistic/Sameness Behaviour was found. Conversely, in the ASD group, more diffuse interlinks between sensory processing difficulties and motor behaviours were significant. In conclusion, the present study confirms the key role of sensory–motor skills in early diagnosis and intervention among children at risk for neurodevelopmental disorders

Application of biological growth risk models to the management of built heritage

La qualità degli spazi interni è fortemente legata alle condizioni igrotermiche che influenzano il comfort degli utenti e i rischi di conservazione del patrimonio edilizio. Inoltre, una gestione incurante di spazi espositivi con numerosi accessi può causare carichi eccessivi di umidità, e conseguenti fenomeni di degrado. In questo lavoro, è stata considerata una sala espositiva rappresentativa del patrimonio costruito. Il rischio di proliferazione biologica è indagato nelle condizioni climatiche di Milano e Barcellona, con diversi ratei di ventilazione e numero di visitatori. I risultati delineano la necessità di politiche informate da analisi avanzate per prevenire il rischio igrotermico, in assenza di impianti, che non è sempre possibile integrare nel patrimonio edilizio storico.The quality of the interior spaces is strongly related to the hygro-thermal conditions which affect the users’ comfort, and may yield to preservation risk for the built heritage. Moreover, careless management of exposition spaces with excessive occupancy may result in moisture loads that promote degradation. In this paper, as a case study, an exposition hall representative of the built heritage is considered. The microbiological growth risk is investigated at two different climate conditions, namely Milan and Barcelona, considering varying ventilation rates and number of visitors. The results outline the need of policies informed by advanced analyses to prevent hygro-thermal risk in the absence of dedicated building services, that cannot always be integrated in built heritage

Virulence-associated genes in Avian Pathogenic Escherichia coli of turkey

50 Escherichia coli (APEC-Avian Pathogenic Escherichia coli) strains and 15 E. coli (AFEC-Avian Faecal Escherichia coli) from turkeys affected by colibacillosis and from healthy turkeys were tested for the presence of eight different virulence-associated genes. Besides, APEC were serotyped. O78 has been the most detected serotyped. The presence of the tested virulence genes was prevalently related to the APEC isolates. With reference to serogroup, all the tested O78 resulted iss and irp2 positive. Besides, tsh e cva/cvi were respectively present in 88.9 and 83.3% of O78. Nevertheless, the finding of a not typeable strains equipped with all the eight tested virulence genes among the APEC isolates suggest the importance of a careful and complete characterisation of the isolate to evaluate the real potential pathogenic attitude of the bacterium

Interfacial Hot Carrier Collection Controls Plasmonic Chemistry

Harnessing non-equilibrium hot carriers from plasmonic metal nanostructures constitutes a vibrant research field. It promises to enable control of activity and selectivity of photochemical reactions, especially for solar fuel generation. However, a comprehensive understanding of the interplay of plasmonic hot carrier-driven processes in metal/semiconducting heterostructures has remained elusive. In this work, we reveal the complex interdependence between plasmon excitation, hot carrier generation, transport and interfacial collection in plasmonic photocatalytic devices, uniquely determining the charge injection efficiencies at the solid/solid and solid/liquid interfaces. Interestingly, by measuring the internal quantum efficiency of ultrathin (14 to 33 nm) single-crystalline plasmonic gold (Au) nanoantenna arrays on titanium dioxide substrates, we find that the performance of the device is governed by hot hole collection at the metal/electrolyte interface. In particular, by combining a solid- and liquid-state experimental approach with ab initio simulations, we show a more efficient collection of high-energy d-band holes traveling in [111] orientation, resulting in a stronger oxidation reaction at the {111} surfaces of the nanoantenna. These results thus establish new guidelines for the design and optimization of plasmonic photocatalytic systems and optoelectronic devices

Near-Unity Absorption in van der Waals Semiconductors for Ultrathin Optoelectronics

We demonstrate near-unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (<15 nm) van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We further fabricate Schottky junction devices using these highly absorbing heterostructures and characterize their optoelectronic performance. Our work addresses one of the key criteria to enable TMDCs as potential candidates to achieve high optoelectronic efficiency

Origine delle tensioni residue: deformazioni plastiche e lavorazioni meccaniche

I processi di produzione dei componenti meccanici spesso comportano l’insorgere di sforzi residuinel materiale. La causa di questi sforzi è da ricercarsi in una deformazione plastica non omogeneache può essere indotta da fenomeni meccanici, termici o chimici prodotti nel materiale durante le fasidi lavorazione sia per deformazione plastica sia per asportazione di truciolo.La geometria del componente, il rapporto di riduzione, il tipo di lubrificazione e le proprietàdel materiale determinano l’entità e la distribuzione degli sforzi residui prodotti nel caso delle operazioniper deformazione plastica. Nelle lavorazioni meccaniche per asportazione di truciolo, invece, gli effettimeccanici e termici sono influenzati dai parametri di processo e dal tipo di materiale.In entrambi i casi la conoscenza dei meccanismi e delle cause che generano gli sforzi residuiè importante per una buona progettazione del componente e del suo ciclo produttivo