A Creative Model for an Interdisciplinary Approach to Service-Learning.

The biological sciences are inherently interdisciplinary and important advances in biology cannot be made without collaboration. Despite the increasing emphasis on interdisciplinarity in higher education, science courses only rarely extend to content outside of the STEM discipline. Classes are typically taught by one faculty member in one discipline.

Post-Traumatic Stress, Trauma-Informed Care, and Compassion Fatigue in Psychiatric Hospital Staff: A Correlational Study.

Assault of staff in psychiatric hospitals is a frequent occurrence, and studies indicate that hospital staff are at risk of developing post-traumatic stress disorder (PTSD). We performed a correlational study with a convenience sample of 172 staff in a psychiatric hospital and compared the rate of traumatic events (TEs), resilience, confidence, and compassion fatigue to PTSD symptoms (PTSS). Regression analyses identified two variables that were unique predictors of PTSS: (1) trauma-informed care (TIC) meeting attendance and (2) burnout symptoms.

Generation of electrospun nanofibers with controllable degrees of crimping through a simple, plasticizer-based treatment.

Electrospun nanofibers with controllable degrees of crimping are fabricated by simply exposing the samples to a plasticizer at preset shrinkage ratios. Compared with their straight counterparts, the crimped nanofibers are able to mechanically mimic native tendon tissue and better protect tendon fibroblasts under uniaxial strains.

Difficulties accepting the loss of a spouse: a precursor for intensified grieving among widowed older adults.

Previous research has identified three distinct factors that make up the Texas Revised Inventory of Grief-Present (TRIG-Present) scale, which tap into grief related thoughts, emotional response, and nonacceptance regarding a loss. In the present study, the authors sought to identify which of these core grief experiences in the early aftermath of loss are predictive of subsequent intensified grieving. Information was collected from 169 conjugally bereaved older adults at 2- and 12-months following the loss of their spouse.

Using well-defined Ag nanocubes as substrates to quantify the spatial resolution and penetration depth of surface-enhanced Raman scattering imaging.

The multiplexing capability and high sensitivity of surface-enhanced Raman scattering (SERS) make this new imaging modality particularly attractive for rapid diagnosis. With 100 nm Ag nanocubes serving as the substrate, this work quantitatively evaluated, for the first time, some of the fundamental parameters of SERS imaging such as blur, spatial resolution and penetration depth. Our results imply that SERS is a high-resolution imaging technique with a blur value of 0.

Improving correlated SERS measurements with scanning electron microscopy: an assessment of the problem arising from the deposition of amorphous carbon.

For surface-enhanced Raman scattering (SERS) substrates with nonspherical symmetry, it is critical to correlate spectroscopy measurements with imaging by scanning electron microscopy (SEM). However, the deposition of carbon resulting from e-beam exposure during SEM imaging contaminates the surface of nanoparticles, potentially preventing their further functionalization with Raman probe molecules. In addition, the deposited carbon leads to unwanted background SERS signals.

Recent Developments in Shape-Controlled Synthesis of Silver Nanocrystals.

This feature article introduces our recent work on understanding the roles played by citrate and poly(vinyl pyrrolidone) (PVP) as capping agents in seed-mediated syntheses of Ag nanocrystals with controlled shapes. We have demonstrated that citrate and PVP selectively bind to Ag(111) and Ag(100) surfaces, respectively, and thus favor the formation of Ag nanocrystals enclosed preferentially by {111} or {100} facets. In addition, we have quantified the coverage density of PVP adsorbed on the surface of Ag nanocubes.

Synthesis of Ag nanobars in the presence of single-crystal seeds and a bromide compound, and their surface-enhanced Raman scattering (SERS) properties.

This Article describes the synthesis of Ag nanobars with different aspect ratios using a seed-mediated method and evaluation of their use for surface-enhanced Raman scattering (SERS). The formation of Ag nanobars was found to critically depend on the introduction of a bromide compound into the reaction system, with ionic salts being more effective than covalent molecules. We examined single-crystal seeds with both spherical and cubic shapes and found that Ag nanobars grown from spherical seeds had much higher aspect ratios than those grown from cubic seeds.

A Facile and General Method for the Encapsulation of Different Types of Imaging Contrast Agents Within Micrometer-Sized Polymer Beads.

Polystyrene (PS) hollow beads with holes on the surfaces are employed as containers for quick loading and encapsulation of a variety of contrast enhancement agents: saline solutions for thermoacoustic tomography, iodinated organic compounds for micro-computed tomography, and perfluorooctane for magnetic resonance. Because of the hole on the surface of the PS hollow bead, the contrast agent to be encapsulated could quickly enter the hollow interior via direct flow rather than slow diffusion through the wall. After loading, the hole on the surface is conveniently sealed by annealing the sample at a temperature (e.

Replacement of Poly(vinyl pyrrolidone) by Thiols: A Systematic Study of Ag Nanocube Functionalization by Surface-Enhanced Raman Scattering.

In this work, we used surface-enhanced Raman scattering (SERS) to monitor the replacement of poly(vinyl pyrrolidone) (PVP) on Ag nanocubes by cysteamine, thiol-terminated PEG, and benzenedithiol. PVP is widely used as a colloidal stabilizer and capping agent to control the shape of Ag (as well as many other noble metals) nanocrystals during synthesis, and to stabilize the final colloidal suspension. However, the surface chemistry of Ag nanocrystals often needs to be tailored for specific applications, so the PVP coating must be removed and/or replaced by other ligands.

Facile synthesis of gold nanorice enclosed by high-index facets and its application for CO oxidation.

A facile method for generating Au nanorice enclosed by high-index facets in high purity. The nanorice shows much higher catalytic activity for CO oxidation than multiply twinned particles of Au enclosed by {111} facets at temperatures below 300 °C.

Generation of hot spots with silver nanocubes for single-molecule detection by surface-enhanced Raman scattering.

This paper presents a simple strategy for the formation of surface-enhanced Raman scattering (SERS) hot spots, or regions with extraordinary large electric-field enhancements, by depositing a silver nanocube on a metal substrate. Our experimental and theoretical results show that hot spots form at the corners of a nanocube in contact with the substrate and the hot spots derived from a single silver nanocube are capable of detecting SERS from a single molecule. By varying the electrical property of the substrate, and the distance between the nanoparticle and the substrate, we show that the substrate can dramatically affect the SERS from a supported nanoparticle.

Seed-mediated synthesis of Ag nanocubes with controllable edge lengths in the range of 30-200 nm and comparison of their optical properties.

Silver nanocubes with edge lengths controllable in the range of 30-200 nm were synthesized using an approach based on seeded growth. The keys to the success of this synthesis are the use of single-crystal Ag seeds to direct the growth and the use of AgNO(3) as a precursor to elemental Ag, where the byproduct HNO(3) can block both the homogeneous nucleation and evolution of single-crystal seeds into twinned nanoparticles. Either spherical (in the shape of a cuboctahedron) or cubic seeds could be employed for this growth process.

Wide-field four-channel fluorescence imager for biological applications.

A wide-field four-channel fluorescence imager has been developed. The instrument uses four expanded laser beams to image a large section (6 mm x 9 mm). An object can be sequentially illuminated with any combination of 408-, 532-, 658-, and 784-nm lasers for arbitrary (down to 1 ms) exposure times for each laser.

Understanding the SERS Effects of Single Silver Nanoparticles and Their Dimers, One at a Time.

This perspective article highlights recent developments in a class of surface-enhanced Raman scattering (SERS) experiments that aim to correlate SERS enhancement factors with the physical parameters of metal nanostructures. In a typical study, the SERS substrate is fabricated by depositing colloidal nanoparticles on a silicon wafer to obtain individual particles isolated from each other, or small aggregates such as dimeric units. With the help of registration marks, the same nanoparticle, or dimer of nanoparticles, can be quickly located under a Raman microscope (for SERS spectra) and a scanning electron microscope (for structural characterization).

Chirality-resolved length analysis of single-walled carbon nanotube samples through shear-aligned photoluminescence anisotropy.

An efficient new method is demonstrated for measuring length distributions of semiconducting single-walled carbon nanotubes (SWCNTs) through analysis of their highly polarized photoluminescence when aligned by shear flows. Instrumentation and procedures are developed to characterize nanotube lengths in bulk suspensions with rapid data acquisition and interpretation. Applying the method with spectrally resolved SWCNT emission provides the first measurements of (n,m)-specific length distributions.