Conditions Of Coverage Research Articles

Polyoxazoline adsorption on silica nanoparticles mediated by host–guest interactions

The objective of this work is to develop an original method of polyoxazoline brush generation based on supramolecular chemistry onto silica nanoparticles. A first layer is realized by adsorption of a polymer bearing β-cyclodextrin units (PβCD). This allows the anchoring of a second layer made of alkyl end-capped poly(2-methyl-2-oxazoline) (POXZ–C n ) via host–guest interactions between the alkyl end groups and the β-cyclodextrin units. The characteristics of the surface layers were studied by dynamic light scattering. A first study of PβCD adsorption allowed to define the conditions of homogeneous PβCD coverage onto the silica surfaces. Then the adsorption of the second polymer onto the PβCD coated nanoparticles was studied as a function of the POXZ–C n solution concentration. Brush layers with chains in extended conformation could be obtained above a critical POXZ–C n concentration. The large thickness sensitivity to the feeding POXZ–C n concentrations allowed to show that the POXZ–C n grafting ratio can be controlled by the POXZ–C n concentrations. In a limited concentration range, the nature of the anchoring end-group (C 12 or C 18) does not influence the shape of the POXZ layer.

The D&T Report

The D&T Report

Constraining the minute amount of audible energy radiated from binary collisions of light plastic spheres in conditions of incomplete angular coverage of the measured pressure

Usually, the energy released as air-coupled sound following a collision is dismissed as negligible. The goal of this Letter is to quantify the value of this small but measurable quantity, since it can be useful to impact studies. Measurements of sound radiation from binary collisions of polypropylene balls were performed in order to constrain the fraction of incident energy radiated as sound in air. In the experiments, one ball is released from rest, directly above a stationary target ball. The transient acoustic waveforms are detected by a microphone rotated about the impact point at a radius of 10 cm. The sound pressure was measured as a function of the polar angle θ (the azimuthal symmetry of the problem was verified by rotating the microphone in the horizontal plane). The angular pattern has two main lobes that are asymmetric with respect to the impact plane. This asymmetry is ascribable to interference and/or scattering effects. Gaps in the acoustic measurements at the "poles" (i.e., around 0° and 180°) pose a challenge similar to that of extrapolating the cosmic microwave background in the galactic "cut." The data was continued in the gaps by polynomial interpolation rather than least-squares fitting, a choice dictated by the accuracy of the reconstructed pattern. The acoustic energy radiated during the impact, estimated by multiplying the collision time by the sound intensity integrated over a spherical surface centered at the impact point, is calculated as four orders of magnitude smaller than the incident energy (0.23 μJ versus 1.6 mJ).

Some thoughts on the future of home hemodialysis

Some thoughts on the future of home hemodialysis

On the phase formation of sputtered hafnium oxide and oxynitride films

Hafnium oxynitride films are deposited from a Hf target employing direct current magnetron sputtering in an Ar–O2–N2 atmosphere. It is shown that the presence of N2 allows for the stabilization of the transition zone between the metallic and the compound sputtering mode enabling deposition of films at well defined conditions of target coverage by varying the O2 partial pressure. Plasma analysis reveals that this experimental strategy facilitates control over the flux of the O− ions which are generated on the oxidized target surface and accelerated by the negative target potential toward the growing film. An arrangement that enables film growth without O− ion bombardment is also implemented. Moreover, stabilization of the transition sputtering zone and control of the O− ion flux without N2 addition is achieved employing high power pulsed magnetron sputtering. Structural characterization of the deposited films unambiguously proves that the phase formation of hafnium oxide and hafnium oxynitride films with the crystal structure of HfO2 is independent from the O− bombardment conditions. Experimental and theoretical data indicate that the presence of vacancies and/or the substitution of O by N atoms in the nonmetal sublattice favor the formation of the cubic and/or the tetragonal HfO2 crystal structure at the expense of the monoclinic HfO2 one.

Lanthanide doped silica nanoparticles applied to multiplexed immunoassays

Luminescent samarium (Sm) and europium (Eu) doped silica nanoparticles (SiO(2) NPs) were investigated for use in multiple target immunoassays. Particles with a diameter of 40 +/- 10 nm were synthesized and applied to multiplexed immunoassays in a single well of an assay plate. The luminescent behavior of the lanthanide doped NPs was compared to conventional dyes in solution and in surface confined model immunoassays against two analytes. Luminescence from the dyes and NPs was detected with an imaging spectroscopic system and this could be processed with a simple least squares procedure. In solution, NPs exhibited linear mixing behaviour while conventional fluorescent dyes required careful control to solution conditions, particularly pH. A conventional dye system consisting of FITC and Cy3 applied to a two analyte model system resulted in up to 70% energy transfer from FITC to Cy3 under conditions of high surface coverage. This made quantitative analysis intractable for unknown samples. The lanthanide doped silica nanoparticles responded well to both analytes (<5% relative std. dev.). The results demonstrate that NPs provide alternatives to conventional dyes due to low susceptibility to pH and related solution conditions, absence of energy transfer, single excitation wavelength range, and high stokes shift. These properties allowed quantitative analysis of multiple analytes in the same well.

Estimating crop coefficients from fraction of ground cover and height

The FAO-56 procedure for estimating the crop coefficient K c as a function of fraction of ground cover and crop height has been formalized in this study using a density coefficient K d. The density coefficient is multiplied by a basal K c representing full cover conditions, K cb full, to produce a basal crop coefficient that represents actual conditions of ET and vegetation coverage when the soil surface is dry. K cb full is estimated primarily as a function of crop height. K cb full can be adjusted for tree crops by multiplying by a reduction factor (F r) estimated using a mean leaf stomatal resistance term. The estimate for basal crop coefficient, K cb, is further modified for tree crops if some type of ground-cover exists understory or between trees. The single (mean) crop coefficient is similarly estimated and is adjusted using a K soil coefficient that represents background evaporation from wet soil. The K c estimation procedure was applied to the development periods for seven vegetable crops grown in California. The average root mean square error between estimated and measured K c was 0.13. The K c estimation procedure was also used to estimate K c during midseason periods of horticultural crops (trees and vines) reported in the literature. Values for mean leaf stomatal resistance and the F r reduction factor were derived that explain the literature K c values and that provide a consistent means to estimate K c over a broad range of fraction of ground cover.

Advanced colloidal techniques for characterization of the effect of electrosteric dispersant on the colloidal stability of nanocrystalline ZrO2 suspension

The adsorption state and dispersion effect of an anionic polyelectrolyte (Dolapix CE64) dispersant on the stability of nanocrystalline ZrO2 suspensions are studied by using adsorption isotherms, sedimentation, TGA, electrokinetic sonic amplitude (ESA) and Auger electron spectroscopy (AES) techniques. It was found that colloidal stability and surface properties of aqueous ZrO2 suspension are closely related to coverage distribution of polyelectrolyte as a function of pH on nanocrystalline ZrO2 particle surface. The amount of polyelectrolyte adsorbed on nanocrystalline ZrO2 particle surface increases greatly with decreasing pHiep (pH 3.72) and increasing the polymer concentration. The results obtained from electroacoustic (ESA) technique and AES spectra of polyelectrolyte adsorbed on nanocrystalline ZrO2 surface proved that both techniques are very effective ways to measure the distribution state of polyelectrolyte on nanocrystalline ceramic powder and reveal how the distribution affect the stability of the suspension. It was found that stabilization can be achieved only when conditions of both Dolapix CE64 ionization and ZrO2 surface coverage are satisfied, suggesting an electrosteric stabilization mechanism. In conclusion, we hypothesized a stabilization model according to the model of two particles approaching to describe the influence of the adsorbed anionic polyelectrolyte configuration on particle surface and the stability of nanocrystalline ZrO2 suspensions.

Estimating the Causal Effects of Media Coverage on Policy‐Specific Knowledge

Policy facts are among the most relevant forms of knowledge in a democracy. Although the mass media seem like an obvious source of policy‐specific information, past research in this area has been plagued by design and methodological problems that have hindered causal inferences. Moreover, few studies include measures of media content, preventing researchers from being able to say what it is about media coverage that influences learning. We advance the literature by employing a simple but underutilized approach for estimating the causal effects of news coverage. Drawing upon a unique collection of cross‐sectional survey data, we make within‐survey/within‐subjects comparisons under conditions of high and low media coverage. We show how the volume, breadth, and prominence of news media coverage increase policy‐specific knowledge above and beyond common demographic factors.

Evaluation of motion correction effect and image quality with the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) (BLADE) and parallel imaging acquisition technique in the upper abdomen

To evaluate motion correction effect and image quality in the upper abdomen with the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) (BLADE) and parallel imaging acquisition technique. A total of 50 consecutive patients underwent abdominal MR imaging. Fat-saturated T2-weighted turbo spin-echo sequences were obtained by respiratory triggering. The subjects were examined with three different conditions of echo train length (ETL), blade width, and percent k-space coverage in the same scanning time: 19/30/100%, 30/30/100%, and 30/52/175%, which were designated as L/C(1), L/C(2), and L/C(3), respectively. The parallel imaging acquisition technique was used to either reduce ETL from 30 to 19 in L/C(1) or increase k-space coverage from 100% to 175% in L/C(3) compared with L/C(2). Motion and streak artifacts, and overall image quality were evaluated visually by two radiologists, independently. Motion and streak artifacts were mostly reduced in L/C(3) condition. The L/C(3) image also gave the best overall image quality compared with other conditions (P < 0.001). The inter-rater reliability for each evaluation agreed well. In upper abdominal BLADE MRI, it was possible to reduce image artifacts and obtain better image quality by increasing the k-space coverage with parallel imaging in the same scanning time.

CMS Finalizes Revisions to Conditions to Participation

CMS Finalizes Revisions to Conditions to Participation

Model of minimum cost heterogeneous sensor network

This paper proposed a minimum cost model for the base station to gather data from local area in the heterogeneous sensor network within a square unit.The amount and energy parameters of two node types were acquired under the conditions of coverage and connectivity and sharp cutoff.It was proved that the energy consumption per unit period of cluster nodes in the annular region increased as the width of the annular region increased when the width of the annular region was not longer than the radius of the center circle.At the same time,the quantity of additional nodes needed in the center circle was also calculated.In experiments,the parameters of approximate and exact solutions were compared,and they tallied well.

The Role of Medical Directors in Dialysis Facilities Series Editor: Robert A. Gutman: Medical Director Responsibilities Regarding Disruptive Behavior in the Dialysis Center—Leading Effective Conflict Resolution

AbstractMedical directors are directly or indirectly responsible for everything that occurs in a dialysis facility. The proposed Conditions of Coverage require medical directors to oversee the process resulting in involuntary discharges from the facility. Involuntary discharges result in high costs to the patient, family, facility and payers. Consequently, End Stage Renal Disease (ESRD) Networks oversee individual facility involuntary discharge rates. A large national survey found that involuntary discharges were due to disruptive behaviors, most commonly nonadherence to medical advice. Medical directors should create an environment designed to assure that disruptive behavior and conflict can be resolved. This is best done by using positive interventions before involuntary discharge, by developing policies and procedures that are implemented continuously and by continually teaching these principles. There are two excellent references about dialysis‐related disruptive behavior and conflict resolution: (1) the Renal Physician Association’s second guideline, “Shared Decision Making in the Appropriate Initiation and Withdrawal from Dialysis,” and (2) The Dialysis Patient Provider Conflict Project. Both will aid medical directors meet their conflict‐resolving responsibilities under the proposed, federal regulations.

D&amp;T Report

D&amp;T Report

The variation of soil temperature and water content of seasonal frozen soil with different vegetation coverage in the headwater region of the Yellow River, China

The variation and distribution of temperature and water moisture in the seasonal frozen soil is an important factor in the study of both the soil water cycle and heat balance within the source region of the Yellow River, especially under the different conditions of vegetation coverage. In this study, the impact of various degrees of vegetation coverage on soil water content and temperature was assessed. Soil moisture (θ v) and soil temperature (T s) were monitored on a daily basis. Measurements were made under different vegetation coverage (95, 70–80, 40–50 and 10%) and on both thawed and frozen soils. Contour charts of T s and θ v as well as a θ v–T s coupling model were developed in order to account for the influence of vegetation cover and the interaction between T s and θ v. It was observed that soil water content affected both the overall range and trend in the soil temperature. The regression analysis of θ v versus T s plots indicated that the soil freezing and thawing processes were significantly affected by vegetation cover changes. Vegetation coverage changes also caused variations in the θ v–T s interaction. The effect of soil water content on soil temperature during the freezing period was larger than during the thawing period. Moreover, the soil with higher vegetation coverage retained more water than that with lower coverage. In the process of freezing, the higher vegetation coverage reduced the rate of the reduction in the soil temperature because the thermal capacity of water is higher than that of soil. Areas with higher vegetation coverage also functioned better for the purpose of heat-insulating. This phenomenon may thus play an important role in the environmental protection and effective uses of frozen soil.

Production of cumulative protons in high-energy hadron-nucleus and nucleus-nucleus interactions

Under conditions of 4π coverage, the production of cumulative protons in π −C, pC, 4HeC, and CC collisions at high energies is studied on the basis of a large statistical sample. The behavior of inclusive cross sections for cumulative-proton production versus the cumulative number β is found to be universal in the sense that it is independent of the type projectile and primary energy. It is established that the mean number of cumulative protons is also independent of the projectile type and primary energy.

Mapeamento da temperatura da superfície terrestre com uso do sensor AVHRR/NOAA

O objetivo deste trabalho foi avaliar a adequação do uso do sensor AVHRR/NOAA (Advanced Very High Resolution Radiometer/National Oceanic and Atmospheric Administration) para mapeamento da temperatura da superfície terrestre (TST) no Estado do Rio Grande do Sul, por meio da comparação entre três algoritmos clássicos. Foram comparados os métodos de Becker &amp; Li, Sobrino et al. e Kerr et al. para estimativa das TST mínimas, utilizando imagens noturnas e logo após o amanhecer. Os dados de emissividade e TST foram obtidos por meio de combinações matemáticas da radiação detectada nas faixas do visível, infravermelho próximo e termal do sensor AVHRR/NOAA. O sensor AVHRR é adequado para o mapeamento de TST para as condições do tipo de cobertura do solo que predominam no Rio Grande do Sul, visto que a TST estimada pelos três métodos testados foi próxima à temperatura do ar medida nos locais selecionados. O método de Sobrino et al. foi o mais adequado.

Surface characterization of polymers by inverse gas chromatography

An inverse gas chromatographic (IGC) study of the sorption properties of macroporous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate), PGME, and PGME modified with ethylene diamine, PGME-en, was presented. At infinite dilution, the thermodynamic parameters of adsorption, the dispersive components of the surface free energies, the acid/base constants and the interaction parameters for the initial and modified copolymer samples were investigated. The adsorption isotherms determined by IGC under conditions of finite surface coverage were used to estimate the surface area, the isosteric heat of adsorption and the adsorption energy distribution on the surface of the initial and modified copolymer samples. .

Predictors of the degree of drug treatment coverage for injection drug users in 94 metropolitan areas in the United States of America

Aims A prior study concluded that drug treatment coverage, defined as the percentage of injection drug users in drug treatment, varied from 1 percent to 39 percent (median 9 percent) in 96 metropolitan statistical areas (MSAs) in the United States. Here, we determine which metropolitan area characteristics are associated with drug treatment coverage. Methods We conducted secondary analysis of official data, including the number of injection drug users in treatment and other variables, for 94 large US MSAs. We estimated the number of injection drug users in these metropolitan areas using previously described methods. We used lagged cross-sectional analyses where the independent variables, chosen on the basis of a Theory of Community Action, preceded the dependent variable (drug treatment coverage) in time. Predictors were determined using ordinary least squares multiple regression and confirmed with robust regression. Results Independent predictors of higher drug treatment coverage for injectors were: presence of organisations that support treatment (unstandardized beta = 1.64; 95 percent CI .59 to 2.69); education expenditures per capita in the MSA (unstandardized beta = .12; 95 percent CI −.34 to 2.69); lower percentage of drug users in treatment who are non-injection drug users (unstandardized beta = −0.18; 95 percent CI −0.24 to −0.12); higher percentage of the population who are non-Hispanic White (unstandardized beta = .14; 95 percent CI .08 to .20); lower per capita long-term debt of governments in the metropolitan area (unstandardized beta = −0.93; 95 percent CI −1.51 to −0.35). Conclusions In conditions of scarce treatment coverage for drug injectors, an indicator of epidemiologic need (the per capita extent of AIDS among injection drug users) does not predict treatment coverage, and competition for treatment slots by non-injectors may reduce injectors’ access to treatment. Metropolitan finances limit treatment coverage. Political variables (racial structures, the presence of organisations that support drug treatment, and budget priorities) may be important determinants of treatment coverage for injectors. Although confidence in these results would be higher if we had used a longitudinal design, these results suggest that further research and action that address structural, political, and other barriers to treatment expansion are sorely needed.

CMS proposed revisions to conditions to participation: Part II—patient care

AbstractIn February 2005 the Centers for Medicare and Medicaid Services (CMS) released proposed conditions of coverage that must be met by all dialysis facilities in order to be reimbursed by the CMS for services provided to federally insured patients. If adopted, these proposed regulations would replace entirely the conditions of coverage as promulgated by CMS in 1976. Part I of this article, which appeared in the March issue of D&amp;T, discussed the (less controversial) patient safety provisions of these proposed regulations. This, the second installment of this three‐part discussion, addresses the far‐reaching provisions of the proposed conditions relative to patient care. Next month, the final installment of this series will address the administrative provisions of the proposed regulations.