379 research outputs found
Acetylene-linked conjugated polymers for sacrificial photocatalytic hydrogen evolution from water
Conjugated organic polymers have shown potential as photocatalysts for hydrogen production by water splitting. Taking advantage of a high throughput screening workflow, two series of acetylene-linked co-polymers were prepared and studied for their potential as photocatalysts for sacrificial hydrogen production from water. It was found that a triethynylbenzene-based polymer with a dibenzo[b,d]thiophene sulfone linker (TE11) had the highest performance in terms of hydrogen evolution rate under visible illumination in the presence of a sacrificial hole-scavenger. Synthetically elaborating the triethynylbenzene linker in TE11 by changing the core and by introducing nitrogen, the resulting hydrogen evolution rate was further increased by a factor of nearly two
Observability and nonlinear filtering
This paper develops a connection between the asymptotic stability of
nonlinear filters and a notion of observability. We consider a general class of
hidden Markov models in continuous time with compact signal state space, and
call such a model observable if no two initial measures of the signal process
give rise to the same law of the observation process. We demonstrate that
observability implies stability of the filter, i.e., the filtered estimates
become insensitive to the initial measure at large times. For the special case
where the signal is a finite-state Markov process and the observations are of
the white noise type, a complete (necessary and sufficient) characterization of
filter stability is obtained in terms of a slightly weaker detectability
condition. In addition to observability, the role of controllability in filter
stability is explored. Finally, the results are partially extended to
non-compact signal state spaces
Cancer Incidence in World Trade Center Rescue and Recovery Workers, 2001–2008
Background: World Trade Center (WTC) rescue and recovery workers were exposed to a complex mix of pollutants and carcinogens. Objective: The purpose of this investigation was to evaluate cancer incidence in responders during the first 7 years after 11 September 2001. Methods: Cancers among 20,984 consented participants in the WTC Health Program were identified through linkage to state tumor registries in New York, New Jersey, Connecticut, and Pennsylvania. Standardized incidence ratios (SIRs) were calculated to compare cancers diagnosed in responders to predicted numbers for the general population. Multivariate regression models were used to estimate associations with degree of exposure. Results: A total of 575 cancers were diagnosed in 552 individuals. Increases above registry-based expectations were noted for all cancer sites combined (SIR = 1.15; 95% CI: 1.06, 1.25), thyroid cancer (SIR = 2.39; 95% CI: 1.70, 3.27), prostate cancer (SIR = 1.21; 95% CI: 1.01, 1.44), combined hematopoietic and lymphoid cancers (SIR = 1.36; 95% CI: 1.07, 1.71), and soft tissue cancers (SIR = 2.26; 95% CI: 1.13, 4.05). When restricted to 302 cancers diagnosed ≥ 6 months after enrollment, the SIR for all cancers decreased to 1.06 (95% CI: 0.94, 1.18), but thyroid and prostate cancer diagnoses remained greater than expected. All cancers combined were increased in very highly exposed responders and among those exposed to significant amounts of dust, compared with responders who reported lower levels of exposure. Conclusion: Estimates should be interpreted with caution given the short follow-up and long latency period for most cancers, the intensive medical surveillance of this cohort, and the small numbers of cancers at specific sites. However, our findings highlight the need for continued follow-up and surveillance of WTC responders
The “One-Person Choir”: A Multidisciplinary Approach to the Development of an Embodied Human–Computer Interface
Relationship between Type-D personality, physical activity behaviour and climacteric symptoms.
A number of factors have been identified which might influence the variation observed in climacteric symptoms in peri- and post-menopausal women. We examined the role of the distressed or Type-D personality and mode of physical activity or exercise on the climacteric symptoms experienced by peri- or post-menopausal women
Hybrid QM/QM Simulations of Excited-State Intramolecular Proton Transfer in the Molecular Crystal 7-(2-Pyridyl)-indole
Phase I study of cisplatin, irinotecan, and epirubicin administered every 3 weeks in patients with advanced solid tumours
The driver mutational landscape of ovarian squamous cell carcinomas arising in mature cystic teratoma
Purpose. We sought to identify the genomic abnormalities in squamous cell carcinomas (SCC) arising in ovarian mature cystic teratoma (MCT), a rare gynaecological malignancy of poor prognosis. Experimental design. We performed copy number, mutational state and zygosity analysis of 151 genes in SCC arising in MCT (n=25) using next-generation sequencing. The presence of high/intermediate risk HPV genotypes was assessed by quantitative PCR. Genomic events were correlated with clinical features and outcome Results. MCT had a low mutation burden with a mean of only 1 mutation per case. Zygosity analyses of MCT indicated four separate patterns, suggesting that MCT can arise from errors at various stages of oogenesis. A total of 244 abnormalities were identified in 79 genes in MCT-associated SCC, and the overall mutational burden was high (mean 10.2 mutations per megabase). No SCC was positive for HPV. The most frequently altered genes in SCC were TP53 (20/25 cases, 80%), PIK3CA (13/25 cases, 52%) and CDKN2A (11/25 cases, 44%). Mutation in TP53 was associated with improved overall survival. In 8/20 cases with TP53 mutations, two or more variants were identified, which were bi-allelic. Conclusions. Ovarian SCC arising in MCT has a high mutational burden with TP53 mutation the most common abnormality. The presence TP53 mutation is a good prognostic factor. SCC arising in MCT share similar mutation profiles to other SCC. Given their rarity, they should be included in basket studies that recruit patients with SCC of other organs
- …