The Positive and Negative Affect Schedule for Children (PANAS-C/P; child and parent versions) yield positive affect (PA) and negative affect (NA) scales that are clinically useful for identifying youth with anxiety and mood problems. Despite the advantages that item response theory (IRT) offers relative to classical test theory with respect to shortening test instruments, no studies to date have applied IRT methodology to the PANAS-C/P scales. In the present study, we thus applied IRT methodology using a school-based development sample (child sample: N0799; parent sample: N0553) and developed a shortened 5-item PA scale (joyful, cheerful, happy, lively, proud) and a 5-item NA scale (miserable, mad, afraid, scared, sad) for the sake of simultaneously increasing the assessment efficiency of the PANAS-C/P scales while improving the psychometric properties of the scales. The reduced PA and NA child scales classified relevant diagnostic groups in a separate clinicreferred validation sample (N0662) just as well as the original PANAS-C child scales and may be used to help identify youth with internalizing disorders in need of mental health services.

Numerous trials demonstrate that monitoring client progress and using feedback for clinical decision-making enhances treatment outcomes, but available data suggest these practices are rare in clinical settings and no psychometrically validated measures exist for assessing attitudinal barriers to these practices. This national survey of 504 clinicians collected data on attitudes toward and use of monitoring and feedback. Two new measures were developed and subjected to factor analysis: The monitoring and feedback attitudes scale (MFA), measuring general attitudes toward monitoring and feedback, and the attitudes toward standardized assessment scales-monitoring and feedback (ASA-MF), measuring attitudes toward standardized progress tools. Both measures showed good fit to their final factor solutions, with excellent internal consistency for all subscales. Scores on the MFA subscales (Benefit, Harm) indicated that clinicians hold generally positive attitudes toward monitoring and feedback, but scores on the ASA-MF subscales (Clinical Utility, Treatment Planning, Practicality) were relatively neutral. Providers with cognitive-behavioral theoretical orientations held more positive attitudes. Only 13.9 % of clinicians reported using standardized progress measures at least monthly and 61.5 % never used them. Providers with more positive attitudes reported higher use, providing initial support for the predictive validity of the ASA-MF and MFA. Thus, while clinicians report generally positive attitudes toward monitoring and feedback, routine collection of standardized progress measures remains uncommon. Implications for the dissemination and implementation of monitoring and feedback systems are discussed.

We use nuclear magnetic resonance spectroscopy methods to quantify the extent of ligand exchange between different types of thiolated molecules on the surface of gold nanoparticles. Specifically, we determine ligand density values for single-moiety ligand shells and then use these data to describe ligand exchange behavior with a second, thiolated molecule. Using these techniques, we identify trends in gold nanoparticle functionalization efficiency with respect to ligand type, concentration, and reaction time as well as distinguish between functionalization pathways where the new ligand may either replace the existing ligand shell (exchange) or add to it ("backfilling"). Specifically, we find that gold nanoparticles functionalized with thiolated macromolecules, such as poly(ethylene glycol) (1 kDa), exhibit ligand exchange efficiencies ranging from 70% to 95% depending on the structure of the incoming ligand. Conversely, gold nanoparticles functionalized with small-molecule thiolated ligands exhibit exchange efficiencies as low as 2% when exposed to thiolated molecules under identical exchange conditions. Taken together, the reported results provide advances in the fundamental understanding of mixed ligand shell formation and will be important for the preparation of gold nanoparticles in a variety of biomedical, optoelectronic, and catalytic applications.

Micron-sized particles of poorly soluble nickel compounds, but not metallic nickel, are established human and rodent carcinogens. In contrast, little is known about the toxic effects of a growing number of Ni-containing materials in the nano-sized range. Here, we performed physicochemical characterization of NiO and metallic Ni nanoparticles and examined their metal ion bioavailability and toxicological properties in human lung epithelial cells. Cellular uptake of metallic Ni and NiO nanoparticles, but not metallic Ni microparticles, was associated with the release of Ni(II) ions after 24-48 h as determined by Newport Green fluorescence. Similar to soluble NiCl₂, NiO nanoparticles induced stabilization and nuclear translocation of hypoxia-inducible factor 1α (HIF-1α) transcription factor followed by upregulation of its target NRDG1 (Cap43). In contrast to no response to metallic Ni microparticles, nickel nanoparticles caused a rapid and prolonged activation of the HIF-1α pathway that was stronger than that induced by soluble Ni(II). Soluble NiCl₂ and NiO nanoparticles were equally toxic to H460 human lung epithelial cells and primary human bronchial epithelial cells; metallic Ni nanoparticles showed lower toxicity and Ni microparticles were nontoxic. Cytotoxicity induced by all forms of Ni occurred concomitant with activation of an apoptotic response, as determined by dose- and time-dependent cleavage of caspases and poly (ADP-ribose) polymerase. Our results show that metallic Ni nanoparticles, in contrast to micron-sized Ni particles, activate a toxicity pathway characteristic of carcinogenic Ni compounds. Moderate cytotoxicity and sustained activation of the HIF-1α pathway by metallic Ni nanoparticles could promote cell transformation and tumor progression.

Discrete gold nanoparticles with diameters between 2 and 3 nm show remarkable properties including enhanced catalytic behavior and photoluminescence. However, tunability of these properties is limited by the tight size range within which they are observed. Here, we report the synthesis of discrete, bimetallic gold-copper nanoparticle alloys (diameter ≅ 2-3 nm) which display photoluminescent properties that can be tuned by changing the alloy composition. Electron microscopy, X-ray photoelectron spectroscopy, inductively coupled plasma mass spectrometry, and pulsed-field gradient stimulated echo (1)H NMR measurements show that the nanoparticles are homogeneous, discrete, and crystalline. Upon varying the composition of the nanoparticles from 0% to 100% molar ratio copper, the photoluminescence maxima shift from 947 to 1067 nm, with excitation at 360 nm. The resulting particles exhibit brightness values (molar extinction coefficient (ε) × quantum yield (Φ)) that are more than an order of magnitude larger than the brightest near-infrared-emitting lanthanide complexes and small-molecule probes evaluated under similar conditions.