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Nanoparticle assembly is a material synthesis strategy that enables precise control of nanoscale structural features. Concepts from traditional crystal growth research have been tremendously useful in predicting and programming the unit cell symmetries of these assemblies, as their thermodynamically favored structures are often identical to atomic crystal analogues. However, these analogies have not yielded similar levels of influence in programming crystallite shapes, which are a consequence of both the thermodynamics and kinetics of crystal growth. Here, we demonstrate kinetic control of the colloidal crystal shape using nanoparticle building blocks that rapidly assemble over a broad range of concentrations, thereby producing well-defined crystal habits with symmetrically oriented dendritic protrusions and providing insight into the crystals' morphological evolution. Counterintuitively, these nonequilibrium crystal shapes actually become more common for colloidal crystals synthesized closer to equilibrium growth conditions. This deviation from typical crystal growth processes observed in atomic or molecular crystals is shown to be a function of the drastically different time scales of atomic and colloidal mass transport. Moreover, the particles are spherical with isotropic ligand grafts, and these kinetic crystal habits are achieved without the need for specifically shaped particle building blocks or external templating or shape-directing agents. Thus, this work provides generalizable design principles to expand the morphological diversity of nanoparticle superlattice crystal habits beyond the anhedral or equilibrium polyhedral shapes synthesized to date. Finally, we use this insight to synthesize crystallite shapes that have never before been observed, demonstrating the ability to both predict and program kinetically controlled superlattice morphologies.

Purpose: Transrectal ultrasound-guided prostate biopsy (TRUS-Bx) is associated with a 1-8% risk of post-biopsy sepsis (PBS). A recent study described an isopropyl alcohol needle washing protocol that significantly decreased PBS rates. The current study examined the efficacy of this technique in our clinic population., Materials and Methods: Data were reviewed for 1250 consecutive patients undergoing TRUS-Bx at the Charlie Norwood VA Medical Center from January 2017 to January 2023. Needle washing was adopted in February 2021. Complications occurring within 30 days after TRUS-Bx were recorded., Results: There were 912 patients in group 1 (without needle washing) and 338 in group 2 (with needle washing). Groups had equivalent demographic features, and men of African descent comprised 70% of patients. Standard 12 core biopsies were done in 83% and 82% in groups 1 and 2, respectively (p = 0.788). Total complication rates were 4% and 2% in groups 1 and 2, respectively (p = 0.077). There were 13 sepsis events in group 1 (1.4%) and none in group 2 (p = 0.027). Clavien-Dindo Grade I-III complications occurred in 25 (2.7%) and 7 (2.1%) patients in groups 1 and 2, respectively (p = 0.505). Standard antibiotic prophylaxis (PO fluoroquinolone and IM gentamicin) was given in 80% and 86% of patients in groups 1 and 2, respectively (p = 0.030). Subset analysis limited to patients who received standard prophylaxis showed a significant difference in sepsis rates (1.5% vs 0%; p = 0.036)., Conclusions: Adoption of isopropyl alcohol needle washing was associated with a significant decrease in PBS events., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The need for higher energy density rechargeable batteries has generated interest in metallic electrodes paired with solid electrolytes. However, impedance growth at the Li metal-solid electrolyte interface due to void formation during cycling at practical current densities and areal capacities, e.g., greater than 0.5 mA cm -2 and 1.5 mAh cm -2 respectively, remains a significant barrier. Here, we show that introducing a wetting interfacial film of Na-K liquid between the Li metal and the Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) solid electrolyte permits reversible stripping and plating of up to 150 μm of Li (30 mAh cm -2 ), approximately 10 times the areal capacity of today's lithium-ion batteries, at current densities above 0.5 mA cm -2 and stack pressures below 75 kPa, all with minimal changes in cell impedance. We further show that this increase in the accessible areal capacity at high stripping current densities is due to the presence of Na-K liquid at the Li stripping interface; this performance improvement is not enabled in the absence of the Na-K liquid. This design approach holds promise for overcoming interfacial stability issues that have heretofore limited the performance of solid-state metal batteries.

The arrangement of nanoscale building blocks into patterns with microscale periodicity is challenging to achieve via self-assembly processes. Here, we report on the phase-transition-driven collective assembly of gold nanoparticles in a thermotropic liquid crystal. A temperature-induced transition from the isotropic to the nematic phase under anchoring-driven planar alignment leads to the assembly of individual nanometer-sized particles into arrays of micrometer-sized agglomerates, whose size and characteristic spacing can be tuned by varying the cooling rate. Phase field simulations coupling the conserved and nonconserved order parameters exhibit a similar evolution of the morphology as the experimental observations. This fully reversible process offers control over structural order on the microscopic level and is an interesting model system for the programmable and reconfigurable patterning of nanocomposites with access to micrometer-sized periodicities.

We present an analysis for metamaterial (MM) enhanced wireless power transfer (WPT) that includes new results revealing the impact of magnetostatic surface waves and their degradation of WPT efficiency. Our analysis shows that the commonly used fixed loss model used by previous works leads to the incorrect conclusion regarding the highest efficeincy MM configuration. Specifically, we show that the "perfect lens" configuration provides lower WPT efficiency enhancement in comparison to many other MM configurations and operating conditions. To understand why, we introduce a model for quantifying loss in MM-enhanced WPT and introduce a new figure of merit on efficiency enhancement, [Formula: see text]. Using both simulation and experimental prototypes, we show that while the "perfect-lens" MM achieves a field enhancement of four times the other configurations considered, its internal loss due to magnetostatic waves significantly reduces its efficiency-enhancement. Surprisingly, all the MM configurations analyzed other than the "perfect-lens" achieved higher efficiency enhancement in simulation and in experiment than the perfect lens., (© 2023. The Author(s).)

Single-crystal nanowires are of broad interest for applications in nanotechnology. However, such wires are subject to both the Rayleigh-Plateau instability and an ovulation process that are expected to lead to their break up into particle arrays. Single crystal Ru nanowires were fabricated with axes lying along different crystallographic orientations. Wires bound by equilibrium facets along their length did not break up through either a Rayleigh-Plateau or ovulation process, while wires with other orientations broke up through a combination of both. Mechanistic insight is provided using a level-set simulation that accounts for strongly anisotropic surface energies, providing a framework for design of morphologically stable nanostructures.

Purpose: Increasing diversity in nursing offers opportunities and challenges. This article addresses considerations for clinical and educational policies when working with Muslim nursing students and suggests changes to facilitate inclusive environments. Approach: This article describes the twofold response of a school of nursing where Muslim nursing students encountered potential limitations in clinical experiences. Faculty conducted a review of literature and examined policies to determine barriers to inclusivity for Muslim nursing students in clinical practice. Outcomes: Few research articles exist to guide construction of inclusive practices. The review of policies for the school of nursing and clinical agencies revealed problematic language and wording that could lead to exclusive practices. Clinical Relevance: For the nursing profession to embrace diversity, faculty must be aware of the discrimination and general lack of knowledge toward Muslim nurses/students in the United States and reasonable accommodation for cultural and religious beliefs.

Liquid droplets sitting on nanowire (NW) tips constitute the starting point of the vapor-liquid-solid method of NW growth. Shape and volume of the droplet have been linked to a variety of growth phenomena ranging from the modification of growth direction, NW orientation, crystal phase, and even polarity. In this work we focus on numerical and theoretical analysis of the stability of liquid droplets on NW tips, explaining the peculiarity of this condition with respect to the wetting of planar surfaces. We highlight the role of droplet pinning at the tip in engineering the contact angle. Experimental results on the characteristics of In droplets of variable volume sitting on the tips or side facets of InAs NWs are also provided. This work contributes to the fundamental understanding of the nature of droplets contact angle at the tip of NWs and to the improvement of the engineering of such nanostructures.

Here, we present a two-step annealing procedure to imprint nanofeatures on SiO 2 starting from metallic microfeatures. The first annealing transforms the microfeatures into gold nanoparticles and the second imprints these nanoparticles into the SiO 2 layer with nanometric control. The resulting nanohole arrays show a high ensemble uniformity. As a potential application, the nanohole mask is used as a selective mask for the Ga self-assisted growth of GaAs nanowires (NWs). Thus, for the first time, a successful implementation of nano-self-imprinting that links high-throughput microlithography with bottom-up NW growth is shown. The beneficial hole morphology of the SiO 2 mask promotes high Ga droplet contact angles with the silicon substrate and the formation of single droplets in the mask holes. This droplet predeposition configuration enables a high vertical yield of NWs. Thus, this article describes a new protocol to grow NW devices that combines simultaneously nanosized holes and parallel processing.

III-V semiconductor nanowires deterministically placed on top of silicon electronic platform would open many avenues in silicon-based photonics, quantum technologies and energy harvesting. For this to become a reality, gold-free site-selected growth is necessary. Here, we propose a mechanism which gives a clear route for maximizing the nanowire yield in the self-catalyzed growth fashion. It is widely accepted that growth of nanowires occurs on a layer-by-layer basis, starting at the triple-phase line. Contrary to common understanding, we find that vertical growth of nanowires starts at the oxide-substrate line interface, forming a ring-like structure several layers thick. This is granted by optimizing the diameter/height aspect ratio and cylindrical symmetry of holes, which impacts the diffusion flux of the group V element through the well-positioned group III droplet. This work provides clear grounds for realistic integration of III-Vs on silicon and for the organized growth of nanowires in other material systems.

Diffusion-induced phase transitions typically change the lattice symmetry of the host material. In battery electrodes, for example, Li ions (diffusing species) are inserted between layers in a crystalline electrode material (host). This diffusion induces lattice distortions and defect formations in the electrode. The structural changes to the lattice symmetry affect the host material's properties. Here, we propose a 2D theoretical framework that couples a Cahn-Hilliard (CH) model, which describes the composition field of a diffusing species, with a phase-field crystal (PFC) model, which describes the host-material lattice symmetry. We couple the two continuum models via coordinate transformation coefficients. We introduce the transformation coefficients in the PFC method to describe affine lattice deformations. These transformation coefficients are modeled as functions of the composition field. Using this coupled approach, we explore the effects of coarse-grained lattice symmetry and distortions on a diffusion-induced phase transition process. In this paper, we demonstrate the working of the CH-PFC model through three representative examples: First, we describe base cases with hexagonal and square symmetries for two composition fields. Next, we illustrate how the CH-PFC method interpolates lattice symmetry across a diffuse phase boundary. Finally, we compute a Cahn-Hilliard type of diffusion and model the accompanying changes to lattice symmetry during a phase transition process.

Most academic-clinical partnerships are described as formal agreements between schools of nursing at research-intensive universities and large teaching hospitals. This article demonstrates less formal versions of academic-clinical partnerships established between a small, private liberal arts university school of nursing and 2 regional clinical agencies. In both exemplars, students, faculty, and staff contributed to evidence-based practice projects. Schools of nursing in non-research-intensive environments can develop right-size academic-clinical partnerships that are beneficial for all parties involved.

The liberal arts and sciences serve as a core part of the educational discipline in nursing curriculum and are believed to undergird abilities for critical-thinking, creativity, and holistic care (Hermann, 2004; McKie, 2012). Over time, science has taken on a more central role in nursing education, despite the acknowledged importance and contributions of liberal arts. The humanities are an essential part of liberal arts education and generally include disciplines such as history, literature, religion, philosophy, architecture, or fine arts (e.g., music, painting, sculpture, drama, or film) (Hermann, 2004). Nursing students identify that liberal arts improve their skills to communicate, think globally, navigate diversity, make decisions, and improve their human selves (McKie, 2012), therefore the purposeful inclusion of liberal arts and humanities into nursing pedagogy should be assured. Schools of nursing seated within liberal arts universities are in a position to take advantage of campus environments that seek to improve student knowledge, skills, abilities, and values (Scott, 2014). When caring for patients with complex medical, psychosocial, spiritual, and economic concerns, the ability to differentiate between what is true among a myriad of competing issues, and to identify solutions to these problems, are critical skills (Scott, 2014). This manuscript describes one type of focused effort by school of nursing (SON) faculty to integrate the humanities on a small, liberal arts campus into the nursing curriculum. The desire to do this led to a large, interdisciplinary project intended to enhance campus, community, faculty, and student opportunities to understand and ponder the complexities involved in caring for patients with Alzheimer's disease (AD)., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Critical thinking is the foundation for nurses' decision making. One school of nursing used the California Critical Thinking Disposition Inventory (CCTDI) to document improvement in critical thinking dispositions., Method: A retrospective study of 96 nursing students' records examined the relationships between the CCTDI and learning outcomes. Correlational statistics assessed relationships between CCTDI scores and cumulative grade point averages (GPA) and scores on two Health Education Systems Incorporated (HESI) examinations. Ordinal regression assessed predictive relationships between CCTDI scores and science course grades and NCLEX-RN success., Results: First-year CCTDI scores did not predict first-year science grades. Senior-year CCTDI scores did not correlate with cumulative GPA or HESI RN Exit Exam scores, but were weakly correlated with HESI Pharmacology Exam scores. CCTDI scores did not predict NCLEX-RN success., Conclusion: This study did not identify meaningful relationships between critical thinking dispositions, as measured by the CCTDI, and important learning outcomes. The results do not support the efficacy of using the CCTDI in nursing education., (Copyright 2016, SLACK Incorporated.)

Methylation of the SKA2 (spindle and kinetochore-associated complex subunit 2) gene has recently been identified as a promising biomarker of suicide risk. Based on this finding, we examined associations between SKA2 methylation, cortical thickness and psychiatric phenotypes linked to suicide in trauma-exposed veterans. About 200 trauma-exposed white non-Hispanic veterans of the recent conflicts in Iraq and Afghanistan (91% male) underwent clinical assessment and had blood drawn for genotyping and methylation analysis. Of all, 145 participants also had neuroimaging data available. Based on previous research, we examined DNA methylation at the cytosine-guanine locus cg13989295 as well as DNA methylation adjusted for genotype at the methylation-associated single nucleotide polymorphism (rs7208505) in relationship to whole-brain cortical thickness, posttraumatic stress disorder symptoms (PTSD) and depression symptoms. Whole-brain vertex-wise analyses identified three clusters in prefrontal cortex that were associated with genotype-adjusted SKA2 DNA methylation (methylation(adj)). Specifically, DNA methylation(adj) was associated with bilateral reductions of cortical thickness in frontal pole and superior frontal gyrus, and similar effects were found in the right orbitofrontal cortex and right inferior frontal gyrus. PTSD symptom severity was positively correlated with SKA2 DNA methylation(adj) and negatively correlated with cortical thickness in these regions. Mediation analyses showed a significant indirect effect of PTSD on cortical thickness via SKA2 methylation status. Results suggest that DNA methylation(adj) of SKA2 in blood indexes stress-related psychiatric phenotypes and neurobiology, pointing to its potential value as a biomarker of stress exposure and susceptibility.

Oxidative stress has been implicated in many common age-related diseases and is hypothesized to play a role in posttraumatic stress disorder (PTSD)-related neurodegeneration (Miller and Sadeh, 2014). This study examined the influence of the oxidative stress-related genes ALOX 12 and ALOX 15 on the association between PTSD and cortical thickness. Factor analyses were used to identify and compare alternative models of the structure of cortical thickness in a sample of 218 veterans. The best-fitting model was then used for a genetic association analysis in White non-Hispanic participants (n=146) that examined relationships between 33 single nucleotide polymorphisms (SNPs) spanning the two genes, 8 cortical thickness factors, and each SNP×PTSD interaction. Results identified a novel ALOX12 locus (indicated by two SNPs in perfect linkage disequilibrium: rs1042357 and rs10852889) that moderated the association between PTSD and reduced thickness of the right prefrontal cortex. A whole-cortex vertex-wise analysis showed this effect to be localized to clusters spanning the rostral middle frontal gyrus, superior frontal gyrus, rostral anterior cingulate cortex, and medial orbitofrontal cortex. These findings illustrate a novel factor-analytic approach to neuroimaging-genetic analyses and provide new evidence for the possible involvement of oxidative stress in PTSD-related neurodegeneration., (Published by Elsevier Ltd.)

The kinetics of Li2 S electrodeposition onto carbon in lithium-sulfur batteries are characterized. Electrodeposition is found to be dominated by a 2D nucleation and growth process with rate constants that depend strongly on the electrolyte solvent. Nucleation is found to require a greater overpotential than growth, which results in a morphology that is dependent on the discharge rate., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Oncology nurses are responsible to be vigilant for patients to keep them safe from harm. Yet, nurse vigilance and its role in preventing error are not well understood. Increased knowledge of how oncology nurses practice vigilance may lead to interventions that enhance nurses' abilities to be vigilant, decrease error rates, and protect patients from harm., Objective: This article describes oncology nurses' lived experiences of vigilance while practicing in an acute care hospital setting., Methods: The study design was an adaptation of Colaizzi's empirical phenomenology. Data were obtained from a purposive sample of oncology registered nurses (n = 7) who were identified as being vigilant by patients and family members, following their own interviews about their experiences of vigilance., Results: Four theme categories indicated the following: (1) nurses use vigilance to keep patients safe; (2) vigilance is incorporated into expert practice over time; (3) barriers impede nurses' abilities to be effectively vigilant; and (4) nurses expect patients and families to participate in vigilance partnerships with them because it enhances the nurses' abilities to be vigilant., Conclusion: Nurse vigilance is a complex phenomenon that is not well understood but is used by nurses in daily practice to protect patients from harm., Implications for Practice: Ways in which nurses can enhance vigilance are identified, as well as barriers to vigilance, which if addressed may promote patient safety and well-being. A theory of vigilance and a measure of it could provide objective feedback, which will enhance nurses' abilities to be effectively vigilant.

In this study, we present atomistic simulations and theoretical analyses that reveal a capillary instability that is intrinsic to wetting geometries characteristic of the vapor-liquid-solid mechanism for nanowire growth. The analysis establishes a transition between axisymmetric and tilted wetting configurations that occurs when the triple line geometry satisfies Young's force-balance condition. The intrinsic nature of the instability is anticipated to be linked to the phenomenon of nanowire kinking in response to changes in environmental conditions, such that the current results may have broad implications for the design of experimental strategies for controlled growth of crystalline nanowires with complex geometries.

A new approach to flow battery design is demonstrated wherein diffusion-limited aggregation of nanoscale conductor particles at ∼1 vol % concentration is used to impart mixed electronic-ionic conductivity to redox solutions, forming flow electrodes with embedded current collector networks that self-heal after shear. Lithium polysulfide flow cathodes of this architecture exhibit electrochemical activity that is distributed throughout the volume of flow electrodes rather than being confined to surfaces of stationary current collectors. The nanoscale network architecture enables cycling of polysulfide solutions deep into precipitation regimes that historically have shown poor capacity utilization and reversibility and may thereby enable new flow battery designs of higher energy density and lower system cost. Lithium polysulfide half-flow cells operating in both continuous and intermittent flow mode are demonstrated for the first time.

An aqueous Li-ion flow cell using suspension-based flow electrodes based on the LiTi2(PO4)3-LiFePO4 couple is demonstrated. Unlike conventional flow batteries, the semi-solid approach utilizes fluid electrodes that are electronically conductive. A model of simultaneous advection and electrochemical transport is developed and used to separate flow-induced losses from those due to underlying side reactions. The importance of plug flow to achieving high energy efficiency in flow batteries utilizing highly non-Newtonian flow electrodes is emphasized.

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946-1975; 1976-2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th century climate change may have been sufficient to have a significant impact on wetland cover cycling. Modeled wetlands in the PPR's western Canadian prairies show the most dramatic effects: a recent trend toward shorter hydroperiods and less dynamic vegetation cycles, which already may have reduced the productivity of hundreds of wetland-dependent species.

We present a phase-field model to study the morphological transitions of surfactant micelles in supersaturated dilute solution. Simulations reveal that multiply connected micellar structure can be produced by interface branching instability of a growing micelle at relatively large supersaturation and intermediate spontaneous curvatures. Two branching mechanisms, i.e., a disk-to-cylinder shape transition and a tip bifurcation process, are identified for disklike and cylindrical micelles, respectively. We propose that dynamic branching at the micelle growth front provides an important kinetic pathway for the formation of branched wormlike micelles that are observed in many surfactant systems.

Evaluating patient-centered care (PCC) is crucial to its improvement. This pilot study tested the feasibility of an electronic format to assess PCC during hospitalization. Using a validated indicator of PCC embedded on a mobile device, 86 older adults evaluated its delivery by registered nurses. Patients older than 85 years rated PCC poorer than those who were younger (r = -0.22; P = .04). The electronic format was appraised as feasible; it performed well and took on average 30 minutes to complete.

Construction of six large dams and reservoirs on the Missouri River over the last 50-75 years has resulted in major landscape changes and alterations in flow patterns, with implications for riparian forests dominated by plains cottonwood (Populus deltoides). We quantified changes in land cover from 1892-1950s and the 1950s-2006 and the current extent and age structure of cottonwood forests on seven segments (two reservoir and five remnant floodplain) comprising 1127 km (53 %) of the unchannelized upper two-thirds of the Missouri River. Riparian forest area declined by 49 %; grassland 61 %; shrubland 52 %; and sandbar habitat 96 %; while agricultural cropland increased six-fold and river/reservoir surface area doubled from 1892 to 2006. Net rates of erosion and accretion declined between the 1892-1950s and 1950s-2006 periods. Accretion exceeded erosion on remnant floodplain segments, resulting in declines in active channel width, particularly in 1950s-2006. Across all study segments in 2006, most cottonwood stands (67 %) were >50 years old, 22 % were 25-50 years old, and only 10 % were <25 years old. Among stands <50 years old, the higher proportion of 25-50 year old stands represents recruitment that accompanied initial post-dam channel narrowing; while declines in sandbar and shrubland area and the low proportion of stands <25 years old suggest declines in geomorphic dynamism and limited recruitment under recent river management. Future conservation and restoration efforts should focus both on limiting further loss of remnant cottonwood stands and developing approaches to restore river dynamics and cottonwood recruitment processes.

Aim: This paper is a report of an analysis of the concept of connectedness., Background: Previous attempts to conceptualize patient-provider relationships were limited in explaining how such relationships are fostered and maintained, and how they influence patient outcomes. Connectedness is a concept that may provide insights into the advantages of patient-provider relationships; however, the usefulness of this concept in health care is limited by its conceptual ambiguity. Although connectedness is widely used to describe other social relationships, little consistency exists among its definitions and measures., Data Sources: Sources identified through CINAHL, OVID, PubMed and PsychINFO databases and references lists of selected articles between 1983 and 2010., Review Methods: A hybrid concept analysis approach was used, involving a combination of traditional concept analysis strategies that included: describing historical conceptualizations, identifying attributes, critiquing existing definitions, examining boundaries and identifying antecedents and consequences., Results: Using five distinct historical perspectives, seven attributes of connectedness were identified: intimacy, sense of belonging, caring, empathy, respect, trust and reciprocity. A broad definition of connectedness, which can be used in the context of patient-provider relationships, was developed. A preliminary theoretical framework of connectedness was derived from the identified antecedents, attributes and consequences., Conclusion: Research efforts to advance the concept of connectedness in patient-provider relationships have been hampered by a lack of conceptual clarity. This concept analysis offers a clearer understanding of connectedness, provides recommendations for future research and suggests practice implications., (© 2011 Blackwell Publishing Ltd.)

A diffuse-interface model for microstructure with an arbitrary number of components and phases was developed from basic thermodynamic and kinetic principles and formalized within a variational framework. The model includes a composition gradient energy to capture solute trapping and is therefore suited for studying phenomena where the width of the interface plays an important role. Derivation of the inhomogeneous free energy functional from a Taylor expansion of homogeneous free energy reveals how the interfacial properties of each component and phase may be specified under a mass constraint. A diffusion potential for components was defined away from the dilute solution limit, and a multi-obstacle barrier function was used to constrain phase fractions. The model was used to simulate solidification via nucleation, premelting at phase boundaries and triple junctions, the intrinsic instability of small particles, and solutal melting resulting from differing diffusivities in solid and liquid. The shape of metastable free energy surfaces is found to play an important role in microstructure evolution and may explain why some systems premelt at phase boundaries and phase triple junctions, whereas others do not.

Percolation thresholds and critical exponents for universal scaling laws are computed for microstructures that derive from phase-transformation processes in two dimensions. The computed percolation threshold for nucleation and growth processes, p(c)≈0.6612, is similar to those obtained by random placement of disks and greater than that of spinodal decomposition, p(c)≈0.4987. Three critical exponents for scaling behavior were computed and do not differ significantly from universal values. The time evolution of a characteristic microstructural length was also computed: For spinodal decomposition, this length grows according to a power law after a short incubation period; for nucleation and growth, there are several transitions in the nature of the growth law. We speculate that the transitions in nucleation and growth derive from competing effects of coalescence at short times and then subsequent coarsening. Short-range order is present, but different, for both classes of microstructural evolution.

Recent studies have linked expression of lectin-like ox-LDL receptor 1 (OLR1) to tumorigenesis. We analyzed microarray data from Olr1 knockout (KO) and wild type (WT) mice for genes involved in cellular transformation and evaluated effects of OLR1 over-expression in normal mammary epithelial cells (MCF10A) and breast cancer cells (HCC1143) in terms of gene expression, migration, adhesion and transendothelial migration. Twenty-six out of 238 genes were inhibited in tissues of OLR1 KO mice; the vast majority of OLR1 sensitive genes contained NF-κB binding sites in their promoters. Further studies revealed broad inhibition of NF-kB target genes outside of the transformation-associated gene pool, with enrichment themes of defense response, immune response, apoptosis, proliferation, and wound healing. Transcriptome of Olr1 KO mice also revealed inhibition of de novo lipogenesis, rate-limiting enzymes fatty acid synthase (Fasn), stearoyl-CoA desaturase (Scd1) and ELOVL family member 6 (Elovl6), as well as lipolytic phospholipase A2 group IVB (Pla2g4b). In studies comparing MCF10A and HCC1143, the latter displayed 60% higher OLR1 expression. Forced over-expression of OLR1 resulted in upregulation of NF-κB (p65) and its target pro-oncogenes involved in inhibition of apoptosis (BCL2, BCL2A1, TNFAIP3) and regulation of cell cycle (CCND2) in both cell lines. Basal expression of FASN, SCD1 and PLA2G4B, as well as lipogenesis transcription factors PPARA, SREBF2 and CREM, was higher in HCC1143 cells. Over-expression of OLR1 in HCC1143 cells also enhanced cell migration, without affecting their adherence to TNFα-activated endothelium or transendothelial migration. On the other hand, OLR1 neutralizing antibody inhibited both adhesion and transmigration of untreated HCC1143 cells. We conclude that OLR1 may act as an oncogene by activation of NF-kB target genes responsible for proliferation, migration and inhibition of apoptosis and de novo lipogenesis genes.

Nanometer length-scale holes (nanopores) are often formed in amorphous materials for fundamental studies of molecular mass transport. In the current study, electron beam irradiation in the transmission electron microscope was used to form nanopores in a crystalline material (Si). Analysis of the nanopores showed that they are formed by knock-on of atoms by the high energy incident electron beam, and surface diffusion is partially responsible for the hour-glass shapes that are found for some nanopores. Energetically favorable three-dimensional shapes of nanopores were simulated, and the nanopores simulated in the model crystalline material were found to be more stable than the nanopores simulated in the amorphous material. The nanopore shape was also found to depend on the nanopore diameter-to-length ratio. Based on the above, we demonstrate the advantage in using a crystalline material for nanopore formation and show that control of the three-dimensional shape of nanopores formed by electron beam irradiation is possible.

Oppositely charged colloidal particles in suspension undergo rapid coagulation in the absence of any repulsive component in the interaction potential. With an added steric component serving as the repulsive force it is possible to order oppositely charged particles, which are also weakly charged, in solution. However given the novel features obtainable for an ordered structure from strong oppositely charged particles it becomes imperative to gain a full understanding of methods that can order these particles. Here we report a simple and rapid layer-by-layer method to order strongly and oppositely charged particles. Although this method is in principle scalable to order multiple layers of oppositely charged particles, herein we report ordering of one layer of positively charged particles onto a substrate made of negatively charged particles. This method utilizes a non-ionic surfactant to induce a steric repulsive force between particles and involves spin-coating to disperse and order particles on a very short time scale. The ordered structure obtained through this process is verified as the structure with one of the lowest interaction energies.

Despite the extremely broad technical applications of the Si/SiO2 structure, the equilibrium wetting properties of silicon oxide on silicon are poorly understood. Here, we produce new results in which a solid-state buffer method is used to systematically titrate oxygen activity about the Si/SiO2 coexistence value. The equilibrium morphology at the Si(001) surface over >8 decades of PO2 about coexistence is revealed to be a uniform sub-stoichiometric SiOx film of sub-nanometer thickness, coexisting with secondary island structures which coarsen with annealing time. A new thermodynamic method using chemical potential to stabilize and control surficial oxides in nanoscale devices is suggested.

This article describes common experiences of African American women breast cancer survivors through poetic analysis. Group-as-a-whole theory and empirical and interpretive phenomenology guided analysis of transcripts from three focus groups (n = 21) of African American breast cancer survivors. Familiarity with transcripts and themes led to awareness of poetic ways in which African American women described experiences. Black feminist literature and African American historical references contextualized survivors' experiences. Poetic interpretations of African American women's breast cancer experiences, from diagnosis to survivorship, were created from transcript dialogues. Verbatim words were used to construct the poems, as often as possible. Eleven poems describe the journey from diagnosis to survivorship as experienced by African American women. The poetry may raise levels of awareness of African American women's breast cancer survivorship experiences. Attention to subtleties that underpin culture within the context of health care environments may help health care providers to improve cultural competence.

Wetlands of the Prairie Pothole Region exist in a matrix of grassland dominated by intensive pastoral and cultivation agriculture. Recent conservation management has emphasized the conversion of cultivated farmland and degraded pastures to intact grassland to improve upland nesting habitat. The consequences of changes in land-use cover that alter watershed processes have not been evaluated relative to their effect on the water budgets and vegetation dynamics of associated wetlands. We simulated the effect of upland agricultural practices on the water budget and vegetation of a semipermanent prairie wetland by modifying a previously published mathematical model (WETSIM). Watershed cover/land-use practices were categorized as unmanaged grassland (native grass, smooth brome), managed grassland (moderately heavily grazed, prescribed burned), cultivated crops (row crop, small grain), and alfalfa hayland. Model simulations showed that differing rates of evapotranspiration and runoff associated with different upland plant-cover categories in the surrounding catchment produced differences in wetland water budgets and linked ecological dynamics. Wetland water levels were highest and vegetation the most dynamic under the managed-grassland simulations, while water levels were the lowest and vegetation the least dynamic under the unmanaged-grassland simulations. The modeling results suggest that unmanaged grassland, often planted for waterfowl nesting, may produce the least favorable wetland conditions for birds, especially in drier regions of the Prairie Pothole Region. These results stand as hypotheses that urgently need to be verified with empirical data.

A thermodynamic diffuse interface analysis predicts that grain boundary transitions in solute absorption are coupled to localized structural order-disorder transitions. An example calculation of a planar grain boundary using a symmetric binary alloy shows that first-order boundary transitions can be predicted as a function of the crystallographic grain boundary misorientation and empirical gradient coefficients. The predictions are compared to published experimental observations.

The shapes and energies of drops on substrates patterned with either holes or posts are computed using Surface Evolver software. The holes and posts are cylindrical in shape and distributed in a 6-fold symmetric pattern. The wetting conditions are such that the liquid does not fill the holes and the interface between the drop and the substrate is composite, i.e., partly solid/liquid and partly liquid/vapor. The sequence of stable drop configurations with increasing volume is analyzed and provides, in part, an explanation for superhydrophobic drop spreading.

We propose a new type of ordered colloid, the "ionic colloidal crystal" (ICC), which is stabilized by attractive electrostatic interactions analogous to those in atomic ionic materials. The rapid self-organization of colloids via this method should result in a diversity of orderings that are analogous to ionic compounds. Most of these complex structures would be difficult to produce by other methods. We use a Madelung summation approach to evaluate the conditions where ICC's are thermodynamically stable. Using this model, we compare the relative electrostatic energies of various structures showing that the regions of ICC stability are determined by two dimensionless parameters representing charge balance and the spatial extent of the electrostatic interactions. Parallels and distinctions between ICC's and classical ionic crystals are discussed. Monte Carlo simulations are utilized to examine the glass transition and melting temperatures, between which crystallization can occur, of a model system having the rocksalt structure. These tools allow us to make a first-order prediction of the experimentally accessible regions of surface charge, particle size, ionic strength, and temperature where ICC formation is probable.

Fragmentation of substance abuse treatment represents a major barrier to effective treatment for individuals with cooccurring substance abuse and mental and physical health disorders. Linkages of substance abuse treatment organizations with primary care and mental health agencies are widely considered to be a feasible way to integrate services. In this study, we analyzed information collected from a national sample of 62 outpatient substance abuse treatment units (OSATs) to understand the extent of services linkages in these organizations and to identify facilitators and barriers to service linkages. Results showed that OSATs had limited service linkages with primary care and mental health providers. The cited barriers to linkages included clients' financial problems, managed care restrictions, and limited organizational capacity. Onsite service provision was implemented in some OSATs. The pattern of service linkages in OSATs appeared to reflect the health needs of substance abuse clients.

: Although treatment of co-occurring behavioral and physical health problems could be facilitated by the linkages between health care providers, it is uncertain how such inter-agency linkages are affected by managed care. We used a sample of 167 service linkages to examine the effects of managed care arrangements on inter-agency communication, coordination, and perceived effectiveness. These linkages were identified based on interviews with 62 outpatient substance abuse treatment units in 2000. Results indicate that frequency of communication and inter-agency coordination are positively related to several managed care arrangements and may moderate the relationships between managed care arrangements and perceived effectiveness.

As previously reported [Opt. Lett. 29, 2791 (2004)], one-dimensional photonic crystals exhibit a decrease in their normal reflectivity if their interfaces are not flat. We show that the homogenization approximation accurately predicts this diminished optical response by comparing results with finite-difference time-domain (FDTD) simulations applied to the same roughened structures. Within the parameter range tested (rms roughness < 20% and rms wavelengths < 100% of the photonic crystal periodicity), the homogenization approximation accurately reproduces the reflectivities obtained by the FDTD simulations, which are much more computationally expensive.

Traditional methods of teaching intracellular biological processes and pathways use figures or flowcharts with the names of molecules linked with arrows. Many veterinary students, presented with such material, simply memorize the names or chemical structures of the molecules and are then likely to forget the material once the examination is completed. To address this problem, the authors designed, created, and field-tested new teaching media that incorporate realistic three-dimensional (3D) animations depicting the dynamic changes that occur in intracellular molecules during cellular activation. Testing found that veterinary students taught using traditional teaching media (e.g., lectures, handouts, textbooks) are proficient in memorizing the names and order of intracellular molecules but unable to appreciate the interactions between these elements or their spatial relationships within cells. In contrast, more than 90% of veterinary students taught using 3D animations not only recall the facts about the intracellular elements but also develop accurate mental images of the interactions among these molecules and their spatial relationships. These findings strongly suggest that the comprehension of complex biological processes by veterinary students can be enhanced by the use of dynamic 3D depictions of these processes in the classroom.

Dielectric reflectors that are periodic in one dimension, also known as one-dimensional photonic crystals (1DPCs), have become extremely useful tools in the optics industry due to the presence of wavelength-tunable photonic bandgaps. However, little is known about the practical effects of manufacturing defects, such as interfacial roughness, on this technologically useful property of 1DPCs. We employ a finite-difference time-domain code to gain further insight into the effect of interfacial roughness on the reflectivity of quarter-wave-tuned 1DPCs in the center of the bandgap at normal incidence. This provides an estimate of the magnitude of the effect of the roughness for even the most-robust incidence conditions.