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Metal–organic frameworks (MOFs) have unique potential in the field of gas sensing due to their ultra-high specific surface area and abundant mesoporous structure. In this paper, a mesoporous Co3O4 hollow polyhedron structure with high specific surface area (141.6 m2 g−1) was synthesized by annealing at the optimum temperature. The gas response of the mesoporous Co3O4 hollow polyhedron structure to volatile organic compounds such as xylene, ethanol, methanol and acetone was systematically tested. The experimental results show that the mesoporous Co3O4 hollow polyhedron structure has the highest sensitivity (21.33) and excellent stability for xylene gas, and the detection limit is low (1 ppm). The excellent sensing performance benefits from large surface area, high oxygen defect concentration and mesoporous structure. [ABSTRACT FROM AUTHOR]

Oxygen vacancies on the surface of the electron transport layer (ETL) can distort the perovskite structure near the interface, inducing unfavorable phases, and, the surface chemical modification of the ETL plays a key role for the efficiency and stability of perovskite solar cells (PSCs). In this study, C6H5K3O7 was introduced as a conductive adhesive to modify the SnO2/perovskite interface. The polar molecule group (–C6H5O7) could react with the perovskite to trigger heterogeneous nucleation over the perovskite precursor film for a high-quality perovskite, which not only decreases the bulk defects, but also interacts with excess PbI2 to passivate the interface defect. Meanwhile, interstitial K+ could modulate the perovskite growth and upshift the energy barrier of ion migration, which significantly suppresses non-radiative recombination. Moreover, –C6H5O7 could react with SnO2 to reduce its surface oxygen vacancies and optimize the band alignment of SnO2, which matches with that of perovskite. These are beneficial for the better interfacial contact of the ETL with the perovskite, forming more channels for electron transfer and achieving self-encapsulation at the buried interface. Therefore, the C6H5K3O7-based PSC achieved a champion efficiency of 24.12% with negligible J–V hysteresis. In addition, its initial power conversion efficiency can remain over 90% after 2400 h storage in dry air with good stability. [ABSTRACT FROM AUTHOR]

Core–shell nanomaterials have led to their fascinating properties in optical applications due to the localized surface plasmon resonance (LSPR). Herein, a mesoporous core–shell Au@Cu2−xS nanomaterial with dual LSPR characteristics is introduced to stabilize and passivate the perovskite/spiro‐OMeTAD interface of perovskite solar cells (PSCs). Thanks to the LSPR, Au@Cu2−xS nanoparticles (NPs) have the potential to enhance the infrared absorption and intensify the local electric field at the perovskite/spiro‐OMeTAD interface. The embedding of the mesoporous Au@Cu2−xS in the spiro‐OMeTAD layer can improve the contact and form "bridges" between perovskite grains and spiro‐OMeTAD. With the help of cationic surfactant cetyltrimethylammonium bromide, these mesoporous Au@Cu2−xS NPs can passivate surface traps and smooth the valence‐band offset at the perovskite/spiro‐OMeTAD interface for hole transferring. Furthermore, the improved hole mobility can offer balanced charge transport and prevent the carrier accumulation at interfaces. As a result, the Au@Cu2−xS(20:10)‐based PSCs achieves a champion efficiency over 22%, higher than that of the Au@Cu2−xS‐based device. [ABSTRACT FROM AUTHOR]

* Context.--Cervical screening in the United States increasingly involves newer US Food and Drug Administration-approved cytologic methods and adjunctive high-risk human papillomavirus (hrHPV) DNA testing. Objective.--To document cervical screening test performance preceding histopathologic cervical intraepithelial neoplasia (CIN) 2/3 diagnoses. Design.--Preceding screening test results with computer-imaged, liquid-based cytology (LBC) and hrHPV results were analyzed for 2827 patients with histopathologic CIN 2/3 diagnoses. Results.--Of 2827 patients with CIN 2/3 diagnoses, 2074 (73.4%) had system LBC findings within 4 months of CIN 2/3 diagnoses: high-grade squamous intraepithelial lesion (n = 862; 41.6%), low-grade squamous intraepithelial lesion (n = 464; 22.4%), atypical squamous cells of undetermined significance (n = 445; 21.5%), atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (n = 288; 13.9%), and atypical glandular cells/adenocarcinoma in situ (n = 15; 0.7%). Of the 2827 patients, 1488 (52.6%) also had earlier system LBC results at more than 4 months to 3 years before CIN 2/3 diagnoses: one or more abnormal LBC results (n = 978; 65.7%), one or more negative LBC results (n = 911; 61.2%), both abnormal and negative LBC (n = 401; 26.9%). Of 807 patients with hrHPV cotest results within 4 months of CIN 2/3 diagnoses, 786 (97.4%) had hrHPV+ results. Of 454 patients who also had earlier hrHPV results at more than 4 months to 3 years before CIN 2/3 diagnoses: 377 (83.0%) had one or more [hrHPV.sup.+] result, 110 (24.2%) had one or more hrHPV' result, and 33 (7.3%) had both positive and negative HPV results. Conclusion.--Patients with histopathologic CIN 2/3 had recent abnormal LBC results, most often, high-grade squamous intraepithelial lesions. Among cotested patients, 97.4% (786 of 807) tested hrHP[V.sup.+}]. However, a significant number of patients tested during an extended period of several years had earlier negative Papanicolaou or negative HPV test results, suggesting the recent development of some CIN 2/3 lesions and supporting the value of cotesting for enhanced detection of other developing, small, inaccessible, or nondiagnostic precursor lesions. (Arch Pathol Lab Med. 2013;137:942-947; doi:10.5858/arpa.2012-0307-OA), The primary goal of cervical screening is the identification and removal of intraepithelial precancerous lesions, which, if left untreated, would, at some future time, become invasive cervical cancer. (1) The [...]