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The measurement of the area density of zinc coatings on steel by X-ray fluorescence is considered from an instalment design point of view. Each of the two general approaches, i.e., measurement of the attenuation of the iron emission line by the zinc coating and measurement of the sine emission line has limitations. Calculations indicate that contrast requirements are best satisfied by the iron attenuation technique in the coating weight interval 0.2-1.2 oz/ft2 per side. Experimental data collected on galvanised and zinc foil samples are presented in support of this contention. Conversely, advantages in the application of the zinc emission method to very thin zinc coatings are pointed out. Spectral resolution is discussed in terms of the ultimate precision and range of coating weight measurements. For the iron attenuation method, it is concluded that a black plate to infinite zinc intensity ratio of approximately 500 permits reasonably precise measurement of zinc foil coating weights in the vicinity of 1.2 oz/ft2 per side. This requirement can be met through the use of a LiF monochroraator crystal and 5 in. of effective 0.020-in. flat plate collimation.
A new X-ray probe attachment for the standard Norelco Vacuum Spectrograph has been developed. The X-ray optical design is essentially the same as that of the Norelco/AMR Microprobe goniometer, being an Ogilvie-type varying curvature Johann focusing device. A light optical system which allows the examination of the specimen during analysis is incorporated in a prealigned module along with the X-ray beam defining aperture. This arrangement assures a constant relationship between beam and optical field centers. Apertures ranging in diameter from 50–500 μ are provided. Data are presented giving the effective size of the specimen area analyzed using each of these apertures. A detailed description of the component parts of the instrument is given.
The smr and qacA/B genes in Staphylococcus aureus confer tolerance to antiseptics and are associated with nosocomial acquisition of infection and underlying medical conditions. Such antiseptic tolerance (AT) genes have also been reported in coagulase-negative staphylococci (CoNS) and enterococci, however, few data are available regarding their prevalence. We sought to describe the frequency of AT genes among bloodstream isolates of S. aureus, CoNS and enterococci at Texas Children’s Hospital (TCH).
Banked CoNS, S. aureus and enterococci isolated from blood cultures collected bewteen October 1, 2016, and October 1, 2017, were obtained from the TCH clinical microbiology laboratory. All isolates underwent polymerase chain reaction (PCR) assay for the qacA/B and smr genes. Medical records were reviewed for all cases.
In total, 103 CoNS, 19 Enterococcus spp, and 119 S. aureus isolates were included in the study, and 80.6% of the CoNS possessed at least 1 AT gene compared to 37% of S. aureus and 43.8% of E. faecalis isolates (P < .001). Among CoNS bloodstream isolates, the presence of either AT gene was strongly associated with nosocomial infection (P < .001). The AT genes in S. aureus were associated with nosocomial infection (P = .025) as well as the diagnosis of central-line–associated bloodstream infection (CLABSI; P = .04) and recent hospitalizations (P < .001). We found no correlation with genotypic AT in E. faecalis and any clinical variable we examined.
Antiseptic tolerance is common among bloodstream staphylococci and E. faecalis isolates at TCH. Among CoNS, the presence of AT genes is strongly correlated with nosocomial acquisition of infection, consistent with previous studies in S. aureus. These data suggest that the healthcare environment contributes to AT among staphylococci.
The use of hedging with commodity futures markets to reduce the price risk in corn production is examined. Both intra-year and inter-year risk are evaluated with different hedging strategies. Strategies involve no hedge, hedge and hold, controlled hedge placement and hold, and in and out hedging. Both technical and forecasting criteria are used to place hedges in the more active strategies. Substantial risk reduction is possible, often without a reduction in price received. Considerable basis risk diminishes the risk reducing properties of a hedge and hold strategy.
Since World War II U.S. Agriculture has seen regional shifts and greater concentration in the production of certain commodities. Technological and infrastructural developments in irrigation, plant varieties, cultivation techniques, transportation, storage, and processing have lowered the barriers of time and space, thus allowing remote regions to compete with and even dominate the traditional production areas. The U.S. potato industry offers an excellent example of this. Processed potatoes have become the dominant food use form and production has shifted westward and become more concentrated both with respect to time and location. In 1947, 44 percent of U.S. potato production was in the seven largest potato states for the fall crop, 35 percent was produced in the nonfall crops, and eight percent was processed. By 1978, 75 percent was produced by the seven leading states for the fall crop, 14 percent in the early nonfall crops, and 59 percent was processed. Because many of these changes involved the adoption of relatively energy intensive techniques, the existence of low and fairly stable energy prices until 1973 aided this change. The increases in energy costs since 1973 raise questions about the long-run stability of recent patterns of production and consumption.
To investigate an outbreak of Burkholderia cepacia complex and describe the measures that revealed the source.
A 629-bed, tertiary-care, pediatric hospital in Houston, Texas.
Pediatric patients without cystic fibrosis (CF) hospitalized in the pediatric and cardiovascular intensive care units.
We investigated an outbreak of B. cepacia complex from February through July 2016. Isolates were evaluated for molecular relatedness with repetitive extragenic palindromic polymerase chain reaction (rep-PCR); specific species identification and genotyping were performed at an independent laboratory. The investigation included a detailed review of all cases, direct observation of clinical practices, and respiratory surveillance cultures. Environmental and product cultures were performed at an accredited reference environmental microbiology laboratory.
Overall, 18 respiratory tract cultures, 5 blood cultures, 4 urine cultures, and 3 stool cultures were positive in 24 patients. Among the 24 patients, 17 had symptomatic infections and 7 were colonized. The median age of the patients was 22.5 months (range, 2–148 months). Rep-PCR typing showed that 21 of 24 cases represented the same strain, which was identified as a novel species within the B. cepacia complex. Product cultures of liquid docusate were positive with an identical strain of B. cepacia complex. Local and state health departments, as well as the CDC and FDA, were notified, prompting a multistate investigation.
Our investigation revealed an outbreak of a unique strain of B. cepacia complex isolated in clinical specimens from non-CF pediatric patients and from liquid docusate. This resulted in a national alert and voluntary recall by the manufacturer.
The role of dynamics in modifying the response of the Arctic ice pack to
inter-annually varying forcings and to climate perturbations is investigated
using simulations from a two-dimensional ice model and a global climate
model (GCM). Inter-annual variability in ice-covered area for 1985-93 is
dominated by ice transport, and different transport regimes affect
substantially the response of the ice pack to climate perturbations. The
thermodynamic-only simulations are more sensitive to initial ice conditions,
and respond less than the dynamk-thermodynamic model to small perturbations,
but with a greater response to larger perturbations. Comparisons of GCM
simulations that use different ice treatments highlights the importance of
considering the distribution of ice thickness and extent in assessing
Delirium is a common neuropsychiatric syndrome that includes clinical subtypes identified by the Delirium Motor Subtyping Scale (DMSS). We explored the concordance between the DMSS and an abbreviated 4-item version in elderly medical inpatients.
Elderly general medical admissions (n = 145) were assessed for delirium using the Revised Delirium Rating scale (DRS-R98). Clinical subtype was assessed with the DMSS (which includes the four items included in the DMSS-4). Motor subtypes were generated for all patient assessments using both versions of the scale. The concordance of the original and abbreviated DMSS was examined.
The agreement between the DMSS and DMSS-4 was high, both at initial and subsequent assessments (κ range 0.75–0.91). Intraclass Correlation Coefficient (ICC) for all three raters for the DMSS was high (0.70) and for DMSS-4 was moderate (0.59). Analysis of the agreement between raters for individual DMSS items found higher concordance in respect of hypoactive features compared to hyperactive.
The DMSS-4 allows for rapid assessment of clinical subtype in delirium and has high concordance with the longer and well-validated DMSS, including over longitudinal assessment. There is good inter-rater reliability between medical and nursing staff. More consistent clinical subtyping can facilitate better delirium management and more focused research effort.
Down through the years the Constitution has not always included all Americans — especially Blacks and women. No such charges have been leveled against the Religious Liberty clauses, though there have been occasions when their protections have been overridden or imperfectly applied. To remind us — as the Framers knew well — that “nothing human can be perfect,” we hear remarks from a distinguished Baptist pastor, an accomplished lawyer, and an eminent civil rights leader, Dr. Benjamin Hooks.
Despite evidence for the effectiveness of structured psychological
therapies for bipolar disorder no psychological interventions have been
specifically designed to enhance personal recovery for individuals with
recent-onset bipolar disorder.
A pilot study to assess the feasibility and effectiveness of a new
intervention, recovery-focused cognitive–behavioural therapy (CBT),
designed in collaboration with individuals with recent-onset bipolar
disorder intended to improve clinical and personal recovery outcomes.
A single, blind randomised controlled trial compared treatment as usual
(TAU) with recovery-focused CBT plus TAU (n = 67).
Recruitment and follow-up rates within 10% of pre-planned targets to
12-month follow-up were achieved. An average of 14.15 h (s.d. = 4.21) of
recovery-focused CBT were attended out of a potential maximum of 18 h.
Compared with TAU, recovery-focused CBT significantly improved personal
recovery up to 12-month follow-up (Bipolar Recovery Questionnaire mean
score 310.87, 95% CI 75.00–546.74 (s.e. = 120.34), P =
0.010, d=0.62) and increased time to any mood relapse
during up to 15 months follow-up (χ2 = 7.64,
P<0.006, estimated hazard ratio (HR) = 0.38, 95%
CI 0.18–0.78). Groups did not differ with respect to medication
Recovery-focused CBT seems promising with respect to feasibility and
potential clinical effectiveness. Clinical- and cost-effectiveness now
need to be reliably estimated in a definitive trial.
Recent developments on the use of the piezoelectric effect in ZnO nanorod-based p-n junctions for energy harvesting applications are presented. Two types of junctions are used. The first is a hybrid p-n device combining the semiconducting polymer poly(3,4-ethylene-dioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) with ZnO nanorods. The second type of junction is an all-inorganic junction between n-type ZnO nanorods and p-type CuSCN. It is shown that both these diodes can be produced on flexible plastic substrates, which generate a voltage output when bent. The voltage output of the ZnO/PEDOT:PSS diodes are measured across a range of resistive loads while bending to find a maximum power point of 12 μWcm-2 at 4 kΩ. It is shown that a voltage output is also generated when this structure is vibrated acoustically. The ZnO/CuSCN diode is sensitized to sunlight with a Ru-based dye to form a photovoltaic device. It is shown that the device efficiency can be increased by application of acoustic vibrations. This is attributed to the electric field generated by the piezoelectric effect in ZnO affecting the charge-carrier recombination at the ZnO surface.
To say that one's home is a significant contributor to social resilience may seem self-evident. Indeed, housing is fundamental to so many areas of social life as to make its importance nearly tautological. Housing and home are a site for and constitutive of crucial social phenomena that include gender, family, child development, health, social relationships, wealth, identity, ethnicity, culture, aging, and many other indicators and determinants of resilience. Indeed, its embeddedness within so many spheres of social life makes its importance challenging to distinguish, leaving it to be taken for granted.
The housing sector has arguably been a critical sector for the unfolding of neoliberalism, although relatively few aspects of this relationship have been examined in the mainstream literature on neoliberalism. Notable neoliberal transformations in the housing sector include the selling off of nearly one-third of Council housing stock in the United Kingdom in the late 1980s and early 1990s under the Right to Buy policy (Ginsburg 2005; Mullins and Murie 2006), the effective elimination of new investments in public housing in Canada in the name of deficit reduction starting in 1993 (Wolfe 1998; Hulchanski 2004), and the stealthy retrenchment from its role as a public landlord by U.S Department of Housing and Urban Development in the United States in favor of a voucher-based system with delivery of housing units by the private rental sector (Schwartz 2010). These represent an important means by which neoliberal governments shrank the state in the 1980s and 1990s consistent with neoliberal doctrine. Although some of these changes could be viewed as part of a continuous evolution of liberal doctrine (especially the Right to Buy policy as a continuation of a historical thrust toward more home ownership), changes in public housing provision to market delivery mechanisms in many countries, including the United States and Germany, signal a neoliberal shift. Most importantly, the establishment and growth of large, publicly funded and publicly managed physical housing stocks and related programs in the early part of the twentieth century has been progressively reversed in the neoliberal era.
Over the last two decades decision makers have sought to address problems with large concentrations of poverty and minority ethnoracial groups in the cities of Western Europe and the Anglo-American world that are the direct result of the manner in which public housing was built in the early postwar era. The United States, Canada, the United Kingdom, and Australia have developed programs that introduce “social mix” into such public housing developments. These initiatives are designed to alter the social dynamics of places with high levels of concentrated poverty and ethnoracial minority groups that are believed to magnify the disadvantages of poverty and marginalization. In this paper, I argue that this is a destigmatization strategy, but not the same kind of destigmatization strategy that has been described in the literature. Using the example of Toronto's Regent Park, a large public housing development near downtown, I develop a research agenda for understanding the gap between a quasi-state agency's efforts to destigmatize public housing sites (“place destigmatization”) and the everyday destigmatization practices and experiences of residents (“personal destigmatization”). The paper begins with a review of the putative mechanisms linking socially mixed public housing redevelopment and outcomes for residents, including social capital, social control, role modelling, and changes to the political economy of place. This review finds little evidence of these effects in the literature. Consequently, I argue for an inductive approach to the study of the outcomes of social mix, rather than the common practice of judging such outcomes against the benchmark of close, intimate relationships between new, middle-class residents and existing public housing residents. I further argue that the “normalization” of the built form that is a major part of socially mixed redevelopment is a form of place destigmatization, and may alter both material practices and representational practices related to stigma, which have very real effects on the everyday experience of residents.
A mineralogical and geochemical study of soils developed from the unmined Coles Hill uranium deposit (Virginia) was undertaken to determine how phosphorous influences the speciation of uranium in an oxidizing soil/saprolite system typical of the eastern US. This paper presents mineralogical and geochemical results that identify and quantify the processes by which uranium has been sequestered in these soils. It was found that uranium is not leached from the saturated soil zone (saprolites) overlying the deposit due to the formation of a sparingly soluble uranyl phosphate mineral of the meta-autunite group. The concentration of uranium in the saprolites is approximately 1000 mg uranium per kg of saprolite. It was also found that a significant amount of uranium was retained in the unsaturated soil zone overlying uranium-rich saprolites. The uranium concentration in the unsaturated soils is approximately 200 mg uranium per kg of soil (20 times higher than uranium concentrations in similar soils adjacent to the deposit). Mineralogical evidence indicates that uranium in this zone is sequestered by a barium-strontium-calcium aluminum phosphate mineral of the crandallite group (gorceixite). This mineral is intimately inter-grown with iron and manganese oxides that also contain uranium. The amount of uranium associated with both the aluminum phosphates (as much as 1.4 weight percent) has been measured by electron microprobe microanalyses and the geochemical conditions under which these minerals formed has been studied using thermodynamic reaction path modeling. The geochemical data and modeling results suggests the meta-autunite group minerals present in the saprolites overlying the deposit are unstable in the unsaturated zone soils overlying the deposit due to a decrease in soil pH (down to a pH of 4.5) at depths less than 5 meters below the surface. Mineralogical observations suggest that, once exposed to the unsaturated environment, the meta-autunite group minerals react to form U(VI)-bearing aluminum phosphates.
In the January 2006 State of the Union address, President Bush announced a new Advanced Energy Initiative, a significant part of which is the Global Nuclear Energy Initiative. Its details were described on February 6, 2006 by the U.S. Secretary of Energy. In summary, it has three parts: (1) a program to expand nuclear energy use domestically and in foreign countries to support economic growth while reducing the release of greenhouse gases such as carbon dioxide. (2) an expansion of the U.S. nuclear infrastructure that will lead to the recycling of spent fuel and a closed fuel cycle and, through transmutation, a reduction in the quantity and radiotoxicity of nuclear waste and its proliferation concerns, and (3) a partnership with other fuel cycle nations to support nuclear power in additional nations by providing small nuclear power plants and leased fuel with the provision that the resulting spent fuel would be returned by the lessee to the lessor. The final part would have the effect of stabilizing the number of fuel cycle countries with attendant non-proliferation value. Details will be given later in the paper.
Performance assessment models of the U. S. repository at Yucca Mountain, Nevada suggest that neptunium from spent nuclear fuel is a potentially important dose contributor. A scientific understanding of how the UO2 matrix of spent nuclear fuel impacts the oxidative dissolution and reductive precipitation of Np is needed to predict the behavior of Np at the fuel surface during aqueous corrosion. Neptunium would most likely be transported as aqueous Np(V) species, but for this to occur it must first be oxidized from the Np(IV) state found within the parent spent nuclear fuel. In this paper we present synchrotron x-ray absorption spectroscopy and microscopy findings that illuminate the resultant local chemistry of neptunium and plutonium within uranium oxide spent nuclear fuel before and after corrosive alteration in an air-saturated aqueous environment. We find the Pu and Np in unaltered spent fuel to have a +4 oxidation state and an environment consistent with solid-solution in the UO2 matrix. During corrosion in an air-saturated aqueous environment, the uranium matrix is converted to uranyl (UO22+) mineral assemblage that is depleted in Np and Pu relative to the parent fuel. The transition from U(IV) in the fuel to a fully U(VI) character across the corrosion front is not sharp, but occurs over a transition zone of ∼ 50 micrometers. We find evidence of a thin (∼ 20 micrometer) layer that is enriched in Pu and Np within a predominantly U(IV) environment on the fuel side of the transition zone. These experimental observations are consistent with available data for the standard reduction potentials for NpO2+/Np4+ and UO22+/U4+ couples, which indicate that Np(IV) may not be effectively oxidized to Np(V) at the corrosion potential of uranium dioxide spent nuclear fuel in air-saturated aqueous solutions.