Molecular recognition of small-cell lung cancer cells using aptamers

Early diagnosis is the way to improve the rate of lung cancer survival, but is almost impossible today due to the lack of molecular probes that recognize lung cancer cells sensitively and selectively. We developed a new aptamer approach for the recognition of specific small-cell lung cancer (SCLC) cell-surface molecular markers. Our approach relies on cell-based systematic evolution of ligands by exponential enrichment (cell-SELEX) to evolve aptamers for whole live cells that express a variety of surface markers representing molecular differences among cancer cells. When applied to different lung cancer cells including those from patient samples, these aptamers bind to SCLC cells with high affinity and specificity in various assay formats. When conjugated with magnetic and fluorescent nanoparticles, the aptamer nanoconjugates could effectively extract SCLC cells from mixed cell media for isolation, enrichment, and sensitive detection. These studies demonstrate the potential of the aptamer approach for early lung cancer detection.     

Three‐State Ferroelastic Switching and Large Electromechanical Responses in PbTiO3 Thin Films

Leveraging competition between energetically degenerate states to achieve large field‐driven responses is a hallmark of functional materials, but routes to such competition are limited. Here, a new route to such effects involving domain‐structure competition is demonstrated, which arises from strain‐induced spontaneous partitioning of PbTiO₃ thin films into nearly energetically degenerate, hierarchical domain architectures of coexisting c/a and a₁ /a₂ domain structures. Using band‐excitation piezoresponse force microscopy, this study manipulates and acoustically detects a facile interconversion of different ferroelastic variants via a two‐step, three‐state ferroelastic switching process (out‐of‐plane polarized c ⁺ → in‐plane polarized a → out‐of‐plane polarized c ^? state), which is concomitant with large nonvolatile electromechanical strains (≈1.25%) and tunability of the local piezoresponse and elastic modulus (>23%). It is further demonstrated that deterministic, nonvolatile writing/erasure of large‐area patterns of this electromechanical response is possible, thus showing a new pathway to improved function and properties.     

Integrating Low-Cost Earth-Abundant Co-Catalysts with Encapsulated Perovskite Solar Cells for Efficient and Stable Overall Solar Water Splitting

Metal halide perovskite solar cells have an appropriate bandgap (1.5–1.6 eV), and thus output voltage (>1 V), to directly drive solar water splitting. Despite significant progress, their moisture sensitivity still hampers their application for integrated monolithic devices. Furthermore, the prevalence of the use of noble metals as co-catalysts for existing perovskite-based devices undermines their use for low-cost H₂ production. Here, a monolithic architecture for stable perovskite-based devices with earth-abundant co-catalysts is reported, demonstrating an unassisted overall solar-to-hydrogen efficiency of 8.54%. The device layout consists of two monolithically encapsulated perovskite (FA_0.80MA_0.15Cs_0.05PbI_2.55Br_0.45) solar cells with low-cost earth-abundant CoP and FeNi(OH)_x co-catalysts as the photocathode and photoanode, respectively. The CoP-based photocathode demonstrates more than 17 h of continuous operation, with a photocurrent density of 12.4 mA cm⁻² at 0 V and an onset potential as positive as ≈1 V versus reversible hydrogen electrode (RHE). The FeNi(OH)_x-based photoanode achieves a photocurrent of 11 mA cm⁻² at 1.23 V versus RHE for more than 13 h continuous operation. These excellent stability and performance demonstrate the potential for monolithic integration of perovskite solar cells and low-cost earth-abundant co-catalysts for efficient direct solar H₂ production.     

热塑性屋面卷材固定系统新选择

屋面行业如同当代生活一样日新月异,新产品、新系统层出不穷.过去10余年间,这一行业经历了非凡的变革,特别是在单层材料领域. 除了全新一代的TPO材料外,热塑性材料家庭还不断迎来新成员:更宽幅的屋面材料,新的自粘技术以及许多新的更大风载的卷材固定方法和产品.     

Participation in counseling programs: High-risk participants are reluctant to accept HIV-prevention counseling.

HIV-prevention intervention effectiveness depends on understanding whether clients with highest need for HIV-prevention counseling accept it. With this objective, a field study with a high-risk community sample from the southeastern United States (N = 350) investigated whether initial knowledge about HIV, motivation to use condoms, condom-use-relevant behavioral skills, and prior condom use correlate with subsequent acceptance of an HIV-prevention counseling session. Ironically, participants with high (vs. low) motivation to use condoms, high (vs. low) condom-use-relevant behavioral skills, and high (vs. low) prior condom use were more likely to accept the HIV-prevention counseling. Moreover, the influence of motivation to use condoms, condom-use-relevant behavioral skills, and prior condom use on acceptance of the counseling was mediated by expectations that the counseling session would be useful. Methods to reduce barriers to recruitment of clients for counseling programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

3D Imaging of Lithium Protrusions in Solid-State Lithium Batteries using X-Ray Computed Tomography

Solid-state lithium batteries will revolutionize the lithium-ion battery and energy storage applications if certain key challenges can be resolved. The formation of lithium-protrusions (dendrites) that can cause catastrophic short-circuiting is one of the main obstacles, and progresses by a mechanism that is not yet fully understood. By utilizing X-ray computed tomography with nanoscale resolution, the 3D morphology of lithium protrusions inside short-circuited solid electrolytes has been obtained for the first time. Distinguishable from adjacent voids, lithium protrusions partially filled cracks that tended to propagate intergranularly through the solid electrolyte, forming a large waved plane in the shape of the grain boundaries. Occasionally, the lithium protrusions bifurcate into flat planes in a transgranular mode. Within the cracks themselves, lithium protrusions are preferentially located in regions of relatively low curvature. The crack volume filled with lithium in two samples is 82.0% and 83.1%, even though they have distinctly different relative densities. Pre-existing pores in the solid electrolyte, as a consequence of fabrication, can also be part-filled with lithium, but do not have a significant influence on the crack path. The crack/lithium-protrusion behavior qualitatively supports a model of propagation combining electrochemical and mechanical effects.     

The team identification–social psychological health model: Sport fans gaining connections to others via sport team identification.

Previous work has consistently found positive relationships between levels of sport team identification and social psychological well-being. According to the Team Identification–Social Psychological Health Model, these effects result from the increased social connections fans generate through their interest in the team. The current pair of investigations was designed to test the hypotheses that (1) team identification is positively related to social well-being and (2) team identification is positively related to social connections. In addition, the interrelationships among the variables were investigated (i.e., tests for mediation and moderation). In Study 1, a sample of 161 college students completed a questionnaire assessing demographics, identification with a local team, connections gained by following the team, and social well-being. Results indicated that, as expected, team identification was positively related to both well-being and social connections. Subsequent analyses failed to find evidence that social connections mediated or moderated the relationship between team identification and social psychological health. Study 2 (N = 199 students from the same university as Study 1) replicated the results of the initial study using a more general measure of social connections (i.e., the Campus Connectedness Scale). Discussion includes the implications for the Team Identification–Social Psychological Health Model and the directionality between identification and social connections. (PsycINFO Database Record (c) 2011 APA, all rights reserved)