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We describe a versatile and facile route for the preparation of Janus microbeads using single emulsion droplet-based microfluidics, in which water droplets that contain a mixture of branched poly(N-isopropylacrylamide)-co-(poly(ethylene glycol)diacrylate)-co-(methacrylic acid) and colloidal particles form the basis of our approach. The colloidal particles, poly(methyl methacrylate) microspheres or titanium dioxide particles, and iron oxide nanoparticles are spatially positioned within the water droplets through gravity and an externally applied magnetic force, respectively. Evaporation of water leads to gel formation of the branched copolymer matrix as a result of physical cross-linking through hydrogen bond interactions, fixing the spatial position of the colloidal particles. The thermo- and pH-responsive nature of the branched poly(N-isopropylacrylamide) (PNIPAm)-based copolymer allows for the disintegration of the polymer network of the Janus microbeads and a triggered release of the colloidal content at temperatures below the lower critical solution temperature (LCST) and at increased pH values.

High Internal Phase Emulsion hydrogels are prepared from waterborne poly(N-isopropylacrylamide) nanogel dispersions which are non-covalently crosslinked through 2-ureido-4[1H] pyrimidinone (UPy) quadruple hydrogen bond groups. The reversible UPy crosslinks allow for the HIPE-hydrogels to be molded into objects which are thermo-responsive in nature.

We investigate the self-assembly behavior of Janus particles with different geometries at a liquid-liquid interface. The Janus particles we focus on are characterized by a phase separation along their major axis into two hemicylinders of different wettability. We present a combination of experimental and simulation data together with detailed studies elucidating the mechanisms governing the adsorption process of Janus spheres, Janus cylinders, and Janus discs. Using the pendant drop technique, we monitor the assembly kinetics following changes in the interfacial tension of nanoparticle adsorption. According to the evolution of the interfacial tension and simulation data, we will specify the characteristics of early to late stages of the Janus particle adsorption and discuss the effect of Janus particle shape and geometry. The adsorption is characterized by three adsorption stages which are based on the different assembly kinetics and different adsorption mechanisms depending on the particle shape.

A convenient route to organogels templated by high internal phase emulsions has been developed. Key is the use of a waterborne polymer latex loaded with a multiple hydrogen bond (MHB) functionality that becomes disentangled and transfers across the oil-water interface forming a gel network in the oil phase via hydrogen bond interactions.

Introduction: Acute myocardial infarction (AMI) continues to contribute to both death and disability in both men and women. The first step in early intervention is an ECG. Atypically presenting patients, especially those who present by self-transport, are more likely to experience delays. The purpose of this study was to evaluate the effect of a new chest pain mnemonic (CPM) as a teaching tool for rapid recognition of AMI patients arriving by self-transport in ED triage in an effort to improve door-to-ECG (DTE) time., Methods: This study is a longitudinal, quasi-experimental quantitative study. Instruction and evaluation of nurses' knowledge related to identification of AMI before and after instruction on the CPM education (intervention) were coordinated by the emergency clinical nurse specialist. The study sample for the educational intervention included 26 nurses (15% of total population) from 4 emergency departments. Ad hoc queries of the National Registry for Myocardial Infarction database for patients arriving by self-transport to the emergency department were done to examine DTE before and after intervention. The pretests and post-tests of the nurses were analyzed with a paired t test, and the pre- and post-intervention DTE times were analyzed by log-linear modeling., Results: Evaluation of nurses' knowledge before and after CPM education indicated an improvement in DTE time, although it was not statistically significant. There was a significant improvement in DTE time for 2 hospitals that was somewhat negated in the aggregate data. There was a noted trend that showed an advantage in DTE time associated with male patients., Discussion: Inclusion of tools such as the CPM in education programs for emergency nurses improved rapid recognition of AMI patients presenting via self-transport to the emergency department. Attention to gender differences in patient presentation should be included in future CPM education, and tools to assist nurses in the early recognition of AMI need to be developed. Investigation regarding intra-hospital differences is warranted., (Copyright © 2011 Emergency Nurses Association. Published by Mosby, Inc. All rights reserved.)

Shared governance (SG), a process for empowering nurses in practice settings, has been widely used for decades. However, despite enthusiasm for the concept, the process is not always successful or falters after successful initiation. To assist nursing leaders trying to implement or maintain SG processes, the author summarizes literature on both human and structural factors that contribute to the success or breakdown of SG practice models. Barriers to implementation and strategies to support implementation, as well as enculturation of SG, are discussed.

A 1 cm long, low-finesse fiber-optic cavity was used as a transducer for the vibrations of the soundboard of an acoustic guitar and of a violin. The reflected light is detected and then amplified and recorded using conventional audio instrumentation. The fiber-optic pickup is found to have a high response range in both amplitude (up to 100 microm displacement) and audio frequency (DC to 20 kHz) and good linearity up to a displacement of 225 microm. The audio noise is found to arise from the fiber-optic cables and, to a lesser extent, from the laser and laser driver.

An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs) and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

Introduction: This article reports on a descriptive study conducted in a Medical Special Needs Shelter with evacuees from Hurricane Gustav in 2008. This shelter was operated by the faculty, students and staff of the University of Texas at Tyler in Tyler, TX., Methods: A descriptive survey approach was used to determine the perception of the shelter experience of evacuees with special medical needs. Evacuees were interviewed by baccalaureate nursing students to assess experiences with the admission process, rest and sleep, food activities, medications and treatments and feelings of safety., Results: Most evacuees were ambulatory, but 48% required human or mechanical assistance. Most had chronic health problems. Overall, the evacuees were pleased with the shelter experience., Discussion: The admission process was expedient and the evacuees felt welcomed and safe in the shelter. Most slept without difficulty, and boredom was not a problem. Assistance with medications or management of medical conditions was provided for 63%. Areas of dissatisfaction were toilet and shower facilities and quality/quantity of food.

A colloid cyst, also called a neuroepithelial cyst, is a slow-growing, benign tumor that occurs in the anterior third ventricle. The cyst typically blocks the foramen of Monro, causing obstructive hydrocephalus involving only the lateral ventricles. The most common presenting sign and symptom of a colloid cyst is headache. Less common presenting signs and symptoms include nausea, vomiting, memory loss, mental status changes, gait disorder, and visual disturbances. Surgical resection is the recommended treatment. Meticulous baseline and ongoing neurological assessments are of paramount importance in the care of a patient with a colloid cyst to promote optimal patient outcomes.

Background: Angiotensin II (Ang II) is associated with a variety of cardiovascular diseases including aneurysm formation. The aim of this study was to evaluate the temporal changes in MT1-matrix metalloproteinase (MMP) and MMP-2 and -9 expression and activity during the course of Ang II induced experimental aneurysm formation., Methods: Apolipoprotein E knockout mice (ApoE null) were infused with either 1000 ng/kg/min of Ang II (n = 20) or saline (n = 20) and then sacrificed at 7, 14, 21, and 28 days of infusion (n = 5/group/strain). Aortic diameters were measured by digital microscopy. Systolic blood pressure (SBP) was measured in the rodent tail. Suprarenal abdominal aortas had MT1-MMP mRNA levels and MMP-2 and MMP-9 mRNA levels and activity quantitated using reverse transcriptase-polymerase chain reaction (rt-PCR) and gelatin zymography, respectively. Statistical analyses included nonpaired t-test, Fisher's exact test, and analysis of variance (ANOVA)., Results: Aneurysms occurred in 40, 40, 20, and 80% of ApoE null-Ang II mice at 7, 14, 21, and 28 days, respectively. An early and significant rise in MT1-MMP mRNA occurred in ApoE null mice infused with Ang II mice, while there was no significant change in MMP-2 or MMP-9 mRNA levels. Total MMP-2 and MMP-9 activity increased over time in ApoE null mice infused with Ang II, peaking at 28 days (ANOVA, P < 0.01). SBP was significantly elevated by 7 days in ApoE null mice infused with Ang II compared to ApoE null mice infused with saline (123 +/- 16 versus 102 +/- 6 mm Hg, P < 0.05)., Conclusions: Angiotensin II induces an early increase in aortic MT1-MMP expression with a subsequent increase in MMP-2 and MMP-9 activity. The process by which these changes cause aneurysm formation warrants further investigation.

Background: Neuromuscular blocking agents used for therapeutic purposes, such as facilitating mechanical ventilation and relieving life-threatening agitation, paralyze patients but leave them fully conscious. Aggressive sedation or analgesia is necessary to reduce awareness, relieve fear, produce comfort, decrease anxiety, induce unconsciousness, and minimize possible complications such as posttraumatic stress syndrome. Little information is available on the extent to which patients experience awareness during therapeutic paralysis., Objectives: To determine and describe the remembered experiences of critical care patients who were given neuromuscular blocking agents and sedatives and/or analgesics to facilitate mechanical ventilation, improve hemodynamic stability, and improve oxygenation., Methods: A phenomenological approach with in-depth interviews with 11 patients was used. Data were analyzed by using the constant comparative approach., Results: A total of 4 themes and 3 subthemes were identified. The first theme was back and forth between reality and the unreal, between life and death; the subtheme was having weird dreams. The second theme was loss of control; the 2 subthemes were (1) fighting or being tied down and (2) being scared. The third theme was almost dying, and the fourth theme was feeling cared for., Conclusions: Patients can remember having both negative and positive experiences during neuromuscular blockade. Steps to improve the experiences of patients receiving neuromuscular blockers include improving assessment parameters, developing and using sedation/analgesia guidelines, and investing in quality improvement programs to provide assessment of awareness during therapeutic paralysis and follow-up and referral as necessary. Ways to decrease the use of neuromuscular blockers would also be useful.

Objective: Our goal was to determine the utility of clinical clues, white blood cell (WBC) and differential counts, and a rapid antigen test for differentiating influenza from coexistent infectious diseases during influenza epidemics., Study Design: Data were collected during 3 consecutive influenza outbreaks over a 2-year period. The information collected included date of onset, symptoms, vaccine status, WBC and differential counts, ZstatFlu test (ZymeTx, Oklahoma City, Ok), and influenza culture. Using culture positivity as the criterion for influenza diagnosis, we compared cases with noncases on each variable independently and by logistic regression. Receiver operating characteristic curves were plotted for WBC count, ZstatFlu, and their combination in an effort to determine the most useful diagnostic strategy., Population: We included consecutive patients presenting to a family practice office with fever, cough, sore throat, myalgia, and/or headache during flu season., Outcomes Measured: The outcomes were sensitivity, specificity, and other measures of test accuracy., Results: Culture-positive cases could not be reliably distinguished from those that were culture negative using symptoms or vaccination status. Both WBC count and ZstatFlu results discriminated fairly well, and their combination did somewhat better. Differential counts were not helpful. WBC counts above 8000 were associated with a low probability of influenza. The sensitivity and specificity of the ZstatFlu were 65% and 83%, respectively., Conclusions: Our data suggest that symptoms and vaccine status do not reliably identify patients with influenza. Use of WBC counts and the ZstatFlu test can be helpful. The sequence, combination, and criteria for use of these tests depend on tradeoffs between undertreatment of influenza cases and the overtreatment of noninfluenza cases, and the cost and benefit projections for individual patients.