Gold nanoparticles decorated with oligo(ethylene glycol) thiols:protein resistance and colloidal stability

The interactions between proteins and gold colloids functionalized with protein-resistant oligo(ethylene glycol) (OEG) thiol, HS(CH(2))(11) (OCH(2)CH(2))(6)OMe (EG(6)OMe), in aqueous solution have been studied by small-angle X-ray scattering (SAXS) and UV-vis spectroscopy. The mean size, 2R, and the size distribution of the decorated gold colloids have been characterized by SAXS. The monolayer-protected gold colloids have no correlations due to the low volume fraction in solution and are stable in a wide range of temperatures (5-70 degrees C, pH (1.3-12.4), and ionic strength (0-1.0 M). In contrast, protein (bovine serum albumin) solutions with concentrations in the range of 60-200 mg/mL (4.6-14.5 vol show a pronounced correlation peak in SAXS, which results from the repulsive electrostatic interaction between charged proteins. These protein interactions show significant dependence on ionic strength, as would be expected for an electrostatic interaction (Zhang et al. J. Phys. Chem. B 2007, 111, 251). For a mixture of proteins and gold colloids, the protein-protein interaction changes little upon mixing with OEG-decorated gold colloids. In contrast, the colloid-colloid interaction is found to be strongly dependent on the protein concentration and the size of the colloid itself. Adding protein to a colloidal solution results in an attractive depletion interaction between functionalized gold colloids, and above a critical protein concentration, c*, the colloids form aggregates and flocculate. Adding salt to such mixtures enhances the depletion effect and decreases the critical protein concentration. The aggregation is a reversible process (i.e., diluting the solution leads to dissolution of aggregates). The results also indicate that the charge of the OEG self-assembled monolayer at a curved interface has a rather limited effect on the colloidal stabilization and the repulsive interaction with proteins.

Magnetite-doped polydimethylsiloxane (PDMS) for phosphopeptide enrichment

Reversible phosphorylation plays a key role in numerous biological processes. Mass spectrometry-based approaches are commonly used to analyze protein phosphorylation, but such analysis is challenging, largely due to the low phosphorylation stoichiometry. Hence, a number of phosphopeptide enrichment strategies have been developed, including metal oxide affinity chromatography (MOAC). Here, we describe a new material for performing MOAC that employs a magnetite-doped polydimethylsiloxane (PDMS), that is suitable for the creation of microwell array and microfluidic systems to enable low volume, high throughput analysis. Incubation time and sample loading were explored and optimized and demonstrate that the embedded magnetite is able to enrich phosphopeptides. This substrate-based approach is rapid, straightforward and suitable for simultaneously performing multiple, low volume enrichments. © the Partner Organisations 2014.

Monitoring changes in thioredoxin and over-oxidised peroxiredoxin in response to exercise in humans

Introduction. Peroxiredoxin (PRDX) and thioredoxin (TRX) are antioxidant proteins that control cellular signalling and redox balance, although their response to exercise is unknown. This study aimed to assess key aspects of the PRDX-TRX redox cycle in response to three different modes of exercise. Methods. Healthy males (n = 10, mean ± SD: 22 ± 3 yrs) undertook three exercise trials on separate days: two steady-state cycling trials at moderate (60% VO2MAX; 27 min, MOD) and high (80% VO2MAX; 20 min, HIGH) intensities, and a low-volume high-intensity interval training trial (10 × 1 min 90% VO2MAX, LV-HIIT). Peripheral blood mononuclear cells were assessed for TRX-1 and over-oxidised PRDX (isoforms I-IV) protein expression before, during, and 30 min following exercise (post + 30). The activities of TRX reductase (TRX-R) and the nuclear factor kappa B (NF-κB) p65 subunit were also assessed. Results. TRX-1 increased during exercise in all trials (MOD, + 84.5%; HIGH, + 64.1%; LV-HIIT, + 205.7%; p < 05), whereas over-oxidised PRDX increased during HIGH only (MOD, - 28.7%; HIGH, + 202.9%; LV-HIIT, - 22.7%; p < .05). TRX-R and NF-κB p65 activity increased during exercise in all trials, with the greatest response in TRX-R activity seen in HIGH (p < 0.05). Discussion. All trials stimulated a transient increase in TRX-1 protein expression during exercise. Only HIGH induced a transient over-oxidation of PRDX, alongside the greatest change in TRX-R activity. Future studies are needed to clarify the significance of heightened peroxide exposure during continuous high-intensity exercise and the mechanisms of PRDX-regulatory control.

Green operations strategy of a luxury car manufacturer

This paper investigates the strategic environmental decisions of a luxury car manufacturer. Through case study research, the investigation sheds light on why and how the company is adopting green technologies. Being pressured by different stakeholders to become greener, luxury car manufacturers carry significant opportunities for environmental improvement given the nature of their manufacturing processes and products. Because of their low-volume production, manufacturers may be able to increase output and still reduce overall emissions when compared to high-volume manufacturers. In the case study company this was found to be possible only because of new ideas brought by a change in ownership. Luxury manufacturers may also be a test-bed for the development and experimentation of green technologies as part of a strategic approach to environmental initiatives. This paper contributes to the fields of green technology adoption and operations strategy in automotive manufacturing groups.

The discrimination and association of float glass and the quantitative analysis of liquids from aerosols and microdrops using laser induced breakdown spectroscopy

Glass is a common form of trace evidence found at many scenes of crimes in the form of small fragments. These glass fragments can transfer to surrounding objects and/or persons and may provide forensic investigators valuable information to link a suspect to the scene of a crime. Since the elemental composition of different glass sources can be very similar, a highly discriminating technique is required to distinguish between fragments that have originated from different sources. ^ The research presented here demonstrates that Laser Induced Breakdown Spectroscopy (LIBS) is a viable analytical technique for the association and discrimination of glass fragments. The first part of this research describes the optimization of the LIBS experiments including the use of different laser wavelengths to investigate laser-material interaction. The use of a 266 nm excitation laser provided the best analytical figures of merit with minimal damage to the sample. The resulting analytical figures of merit are presented. The second part of this research evaluated the sensitivity of LIBS to associate or discriminate float glass samples originating from the same manufacturing plants and produced at approximately the same time period. Two different sample sets were analyzed ranging in manufacturing dates from days to years apart. Eighteen (18) atomic emission lines corresponding to the elements Sr, K, Fe, Ca, Al, Ba, Na, Mg and Ti, were chosen because of their detection above the method detection limits and for presenting differences between the samples. Ten elemental ratios producing the most discrimination were selected for each set. When all the ratios are combined in a comparison, 99% of the possible pairs were discriminated using the optimized LIBS method generating typical analytical precisions of ∼5% RSD. ^ The final study consisted of the development of a new approach for the use of LIBS as a quantitative analysis of ultra-low volume solution analysis using aerosols and microdrops. Laser induced breakdown spectroscopy demonstrated to be an effective technique for the analysis of as low as 90 pL for microdrop LIBS with 1 pg absolute LOD and 20 µL for aerosol LIBS with an absolute LOD of ∼100 fg.^

Quality of experience evaluation of voice communication: an affect-based approach

Voice communication systems such as Voice-over IP (VoIP), Public Switched Telephone Networks, and Mobile Telephone Networks, are an integral means of human tele-interaction. These systems pose distinctive challenges due to their unique characteristics such as low volume, burstiness and stringent delay/loss requirements across heterogeneous underlying network technologies. Effective quality evaluation methodologies are important for system development and refinement, particularly by adopting user feedback based measurement. Presently, most of the evaluation models are system-centric (Quality of Service or QoS-based), which questioned us to explore a user-centric (Quality of Experience or QoE-based) approach as a step towards the human-centric paradigm of system design. We research an affect-based QoE evaluation framework which attempts to capture users' perception while they are engaged in voice communication. Our modular approach consists of feature extraction from multiple information sources including various affective cues and different classification procedures such as Support Vector Machines (SVM) and k-Nearest Neighbor (kNN). The experimental study is illustrated in depth with detailed analysis of results. The evidences collected provide the potential feasibility of our approach for QoE evaluation and suggest the consideration of human affective attributes in modeling user experience.

Alteração do estado trófico durante um evento de seca prolongada e seus impactos na biomassa algal de um manancial tropical da região semiárida

The main consequence of eutrophication is an increase in algal biomass, mainly cyanobacterial blooms. The high evaporation and low precipitation, characteristics of semiarid regions, contribute to the nutrients availability increase in drought periods and consequent aggravation of eutrophic condition in reservoirs. Climate changes tend to intensify eutrophication symptoms, mostly in a semiarid region. Therefore, the aim of this study was to evaluate the impact of an extended drought in algal biomass in Parelhas’s Boqueirão, a mesotrophic reservoir located in a semiarid tropical region. The low volume was associated to water quality degradation and to the high nutrients concentrations and low water transparency. The increase in nutrients availability in the water column, consequence of reduced precipitation and low reservoir’s volume, provided the necessary resources for algal growth and allowed a change in trophic state in Boqueirão reservoir. This study showed how an extended drought decreases water quality. The effect of drought in Boqueirão was late detected due to the reservoir´s low initial nutrients concentration. The reservoir´s volume reduction increased the nutrient availability along with the algal biomass increase and the reservoir´s trophic state change of mesotrophic to eutrophic.

Circumarctic wetland dataset based on ENVISAT ASAR Global Monitoring Mode with links to geotiff image and NetCDF files (2005-01 to 2011-12)

A circumpolar representative and consistent wetland map is required for a range of applications ranging from upscaling of carbon fluxes and pools to climate modelling and wildlife habitat assessment. Currently available data sets lack sufficient accuracy and/or thematic detail in many regions of the Arctic. Synthetic aperture radar (SAR) data from satellites have already been shown to be suitable for wetland mapping. Envisat Advanced SAR (ASAR) provides global medium-resolution data which are examined with particular focus on spatial wetness patterns in this study. It was found that winter minimum backscatter values as well as their differences to summer minimum values reflect vegetation physiognomy units of certain wetness regimes. Low winter backscatter values are mostly found in areas vegetated by plant communities typically for wet regions in the tundra biome, due to low roughness and low volume scattering caused by the predominant vegetation. Summer to winter difference backscatter values, which in contrast to the winter values depend almost solely on soil moisture content, show expected higher values for wet regions. While the approach using difference values would seem more reasonable in order to delineate wetness patterns considering its direct link to soil moisture, it was found that a classification of winter minimum backscatter values is more applicable in tundra regions due to its better separability into wetness classes. Previous approaches for wetland detection have investigated the impact of liquid water in the soil on backscatter conditions. In this study the absence of liquid water is utilized. Owing to a lack of comparable regional to circumpolar data with respect to thematic detail, a potential wetland map cannot directly be validated; however, one might claim the validity of such a product by comparison with vegetation maps, which hold some information on the wetness status of certain classes. It was shown that the Envisat ASAR-derived classes are related to wetland classes of conventional vegetation maps, indicating its applicability; 30% of the land area north of the treeline was identified as wetland while conventional maps recorded 1-7%.

Skapa förutsättningar för att implementera Lean production i en tillverkningsprocess som kännetecknas av HVLV : - En fallstudie på Tibrokök Sverige AB

Idag är det vanligt att företagen konkurrerar med produkter som innefattar en fysisk vara som har utvidgats med olika tjänster för att kunna tillfredsställa kundens behov. I takt med detta ökar produkternas komplexitet och högre krav ställs på leverantörerna. Denna utveckling har lett till att många företag som tillverkar produkter med hög variation måste arbeta helt kundorderstyrt för att kunna tillgodose kundernas ökande krav. Företagen som tillverkar dessa komplexa produkter har en tillverkning som karaktäriseras av hög variation och låg volym vilket benämns med förkortningen HVLV. Utmaningen för dessa HVLV-företag ligger i att ha en hög produktmixflexibilitet med så låg resursanvändning som möjligt. För att effektivisera verksamheten har många företag därför intresserat sig för Lean production som har visat sig vara ett framgångsrikt koncept för tillverkande företag runt om i världen som effektiviserat sin produktion. Ett flertal artiklar har uppmärksammat begränsningar vid implementeringen av Lean production i HVLV-miljöer. Artiklar pekar vidare på behovet av ytterligare forskning kring Lean productions applicerbarhet i HVLV-miljöer och detta var uppkomsten till examensarbetets bakgrund och syfte. En fallstudie har genomförts på Tibrokök som är ett företag med en helt kundorderstyrd produktion som kännetecknas av HVLV. Med hjälp av fallstudien syftar examensarbetet till att undersöka om verktygen processkartläggning inkl. tidsstudier och layoutflödesdiagram kan bidra till att skapa förutsättningar för implementering av Lean production i en enskild tillverkningsprocess i en HVLV-miljö. Trots att verktygen har behövt anpassas något så anses de ha varit användbara och bidragande till skapandet av förutsättningar för implementering av Lean production i denna HVLV-miljö. Detta eftersom vi kunde identifiera många orsaker till slöseri samt ta fram ett förslag som skapar effektiviseringar av Tibroköks ytbehandlingsprocess i det framtida läget.

Exploring Forensic Nursing Ethics and Practice: Roles, Loyalties and Photodocumentation Practices

Thesis (Ph.D.)--University of Washington, 2016-08

Automatic Incident Detection and Driver Warning in PORTICO.

This paper focuses on the low-volume incident detection and subsequent driver warning objectives of the PORTICO project. It proposes Automatic Incident Detection (AID) which uses a multimodel approach comprised of a number of different algorithms. A set of thresholds and conditions are defined which determine which algorithm(s) need to indicate an incident under different traffic conditions in order to trigger an alarm

Shape and chemically anisotropic colloidal particles: A theoretical study of their structure, phase behavior, and slow dynamics

A detailed non-equilibrium state diagram of shape-anisotropic particle fluids is constructed. The effects of particle shape are explored using Naive Mode Coupling Theory (NMCT), and a single particle Non-linear Langevin Equation (NLE) theory. The dynamical behavior of non-ergodic fluids are discussed. We employ a rotationally frozen approach to NMCT in order to determine a transition to center of mass (translational) localization. Both ideal and kinetic glass transitions are found to be highly shape dependent, and uniformly increase with particle dimensionality. The glass transition volume fraction of quasi 1- and 2- dimensional particles fall monotonically with the number of sites (aspect ratio), while 3-dimensional particles display a non-monotonic dependence of glassy vitrification on the number of sites. Introducing interparticle attractions results in a far more complex state diagram. The ideal non-ergodic boundary shows a glass-fluid-gel re-entrance previously predicted for spherical particle fluids. The non-ergodic region of the state diagram presents qualitatively different dynamics in different regimes. They are qualified by the different behaviors of the NLE dynamic free energy. The caging dominated, repulsive glass regime is characterized by long localization lengths and barrier locations, dictated by repulsive hard core interactions, while the bonding dominated gel region has short localization lengths (commensurate with the attraction range), and barrier locations. There exists a small region of the state diagram which is qualified by both glassy and gel localization lengths in the dynamic free energy. A much larger (high volume fraction, and high attraction strength) region of phase space is characterized by short gel-like localization lengths, and long barrier locations. The region is called the attractive glass and represents a 2-step relaxation process whereby a particle first breaks attractive physical bonds, and then escapes its topological cage. The dynamic fragility of fluids are highly particle shape dependent. It increases with particle dimensionality and falls with aspect ratio for quasi 1- and 2- dimentional particles. An ultralocal limit analysis of the NLE theory predicts universalities in the behavior of relaxation times, and elastic moduli. The equlibrium phase diagram of chemically anisotropic Janus spheres and Janus rods are calculated employing a mean field Random Phase Approximation. The calculations for Janus rods are corroborated by the full liquid state Reference Interaction Site Model theory. The Janus particles consist of attractive and repulsive regions. Both rods and spheres display rich phase behavior. The phase diagrams of these systems display fluid, macrophase separated, attraction driven microphase separated, repulsion driven microphase separated and crystalline regimes. Macrophase separation is predicted in highly attractive low volume fraction systems. Attraction driven microphase separation is charaterized by long length scale divergences, where the ordering length scale determines the microphase ordered structures. The ordering length scale of repulsion driven microphase separation is determined by the repulsive range. At the high volume fractions, particles forgo the enthalpic considerations of attractions and repulsions to satisfy hard core constraints and maximize vibrational entropy. This results in site length scale ordering in rods, and the sphere length scale ordering in Janus spheres, i.e., crystallization. A change in the Janus balance of both rods and spheres results in quantitative changes in spinodal temperatures and the position of phase boundaries. However, a change in the block sequence of Janus rods causes qualitative changes in the type of microphase ordered state, and induces prominent features (such as the Lifshitz point) in the phase diagrams of these systems. A detailed study of the number of nearest neighbors in Janus rod systems reflect a deep connection between this local measure of structure, and the structure factor which represents the most global measure of order.

Anticorpos anti-trypanosoma cruzi como preditivos de infecção por leishmania infantum

Leishmania infantum and Trypanosoma cruzi are trypanosomatids of medical importance and are, respectively, the etiologic agents of visceral leishmaniasis (VL) and Chagas disease (CD) in Brazil. People infected with L. infantum or T. cruzi may develop asymptomatically, enabling the transmission of pathogens through blood transfusion and / or organs. The assessment of the infection by T. cruzi is included among the tests performed for screening blood donors in Brazil, however, there is no availability of tests for Leishmania. Serological tests for T. cruzi are very sensitive, but not specific, and may have cross-reactions with other microorganisms. Thus, the aim of this study was to determine the prevalence of Leishmania infection in blood donors and assess whether the serological test for T. cruzi detect L. infantum. Among the 300 blood samples from donors, discarded in 2011, 61 were T. cruzi positive, 203 were from donors with other infections and 36 were from handbags with low blood volume, but without infection. We also assessed 144 samples from donors without infections and able to donate blood, totaling 444 subjects. DNA was extracted from blood samples of all to perform quantitative PCR (qPCR) to detect Leishmania DNA. The buffy coat obtained from all samples was grown in Schneider medium supplemented and NNN. All samples were evaluated for the presence of anti-Leishmania antibody. The serological results indicate a percentage of 22% of Leishmania infection in blood samples obtained from discarded bags. A total of 60% of samples positive in ELISA for T. cruzi were negative by IFI, used as confirmatory test, ie 60% false positive for Chagas. Among these samples false positive for Chagas, 72% were positive by ELISA for Leishmania characterizing the occurrence of cross reaction between serologic assays. Of the 300 cultures performed, 18 grew parasites that were typed by qPCR and specific isoenzymes, found the species Leishmania infantum crops. Among the 18 cultures, 4 were purged from scholarships for low volume and all negative serology blood bank, thus demonstrating that there is a real risk of Leishmania transmission via transfusion. It is concluded that in an area endemic for leishmaniasis in Brazil, serological diagnosis performed to detect infection by T. cruzi among blood donors can identify infection by L. infantum and although cause false positive for Chagas, this cross-reactivity reduces the risk of Leishmania infection via blood transfusion, since tests are not applied specific detection of the parasite. In this way, there remains the need to discuss the implementation of a specific serological screening test for Leishmania in endemic countries such as Brazil

Dysprosium transport in Nd-Fe-B pellets

The addition of heavy rare earth (RE) elements to Nd2Fe14B based magnets to form (Nd,Dy)2Fe14B is known to increase the coercivity and high temperature performance required for hybrid vehicle electric motors and other extreme temperature applications. Attempts to conserve heavy rare earth elements for high temperature (RE)2Fe14B based magnets have led to the development of a grain boundary diffusion process for bulk magnets. This process relies on transport of a heavy rare earth, such as Dy, into a bulk Nd2Fe14B magnet along pores, a low volume fraction of eutectic liquid along grain boundary grain triple junctions and grain boundaries. This enriches the grain surfaces in Dy through the thickness of the bulk magnet, leading to larger increases coercivity with a smaller Dy concentration than can be achieved with homogeneous alloys. Attempts to carry out the same process during sintering require significant control of Dy transport efficiency. The macroscopic transport of Dy in Nd2.7Fe14B1.4 based powder packs is studied using a 'layered' pellet, where Nd2.7Fe14B1.4powder is an interlayer and Dy source as a center layer. The sintering of this layered pellet provided evidence for very large effective diffusion lengths aided by Dy rich liquid flow through connected porosity. Approaches to controlling Dy transportation include decreasing the liquid phase transport capability of the powder pack by increasing the melting point of the Dy source and the decreasing amount of RE rich liquid in the powder packs. The solid-liquid reaction is studied in which melt spun Nd2.7Fe14B1.4 ribbons are PVD coated with Dy-Fe eutectic composition and then thermally treated. The resulting microstructure from the reaction between Dy-Fe eutectic coating and Nd2.7Fe14B1.4 ribbon is interpreted as support for a proposed dissolution/reprecipitation process between solid and liquid phases. The estimate the diffusion coefficient and the effective diffusion length of Dy sources in Nd2.7Fe14B1.4 layered pellets and melt spun ribbons were obtained from the calculation of Fick's second law combined with EDS results from the experiment. The results indicate that the effective diffusion coefficient of Dy in the layered pellets is higher than the diffusion in ribbons due to its higher porosity than ribbons.

Functional outcomes in the Cleft Care UK study - Part 3:oral health and audiology

OBJECTIVES: To compare oral health and hearing outcomes from the Clinical Standards Advisory Group (CSAG, 1998) and the Cleft Care UK (CCUK, 2013) studies. SETTING AND SAMPLE POPULATION: Two UK-based cross-sectional studies of 5-year-olds born with non-syndromic unilateral cleft lip and palate undertaken 15 years apart. CSAG children were treated in a dispersed model of care with low-volume operators. CCUK children were treated in a centralized, high volume operator system. MATERIALS AND METHODS: Oral health data were collected using a standardized proforma. Hearing was assessed using pure tone audiometry and middle ear status by otoscopy and tympanometry. ENT and hearing history were collected from medical notes and parental report. RESULTS: Oral health was assessed in 264 of 268 children (98.5%). The mean dmft was 2.3, 48% were caries free, and 44.7% had untreated caries. There was no evidence this had changed since the CSAG survey. Oral hygiene was generally good, 96% were enrolled with a dentist. Audiology was assessed in 227 of 268 children (84.7%). Forty-three per cent of children received at least one set of grommets--a 17.6% reduction compared to CSAG. Abnormal middle ear status was apparent in 50.7% of children. There was no change in hearing levels, but more children with hearing loss were managed with hearing aids. CONCLUSIONS: Outcomes for dental caries and hearing were no better in CCUK than in CSAG, although there was reduced use of grommets and increased use of hearing aids. The service specifications and recommendations should be scrutinized and implemented.