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Purpose: To evaluate pre- and post-operative resonance, surgical technique, revision rate, and revision indication among syndromic and non-syndromic children with velopharyngeal insufficiency (VPI)., Materials and Methods: A systematic review was conducted through July 2022. Children surgically treated for VPI were included. A meta-analysis of single means, proportions, comparison of proportions, and mean differences with 95 % confidence interval [CI] was conducted., Results: Twenty-three articles (n = 1437) were included in the analysis. The most common surgery was Sphincter Pharyngoplasty (SP), 62.6 % [31.3-88.9] for syndromic and 76.3 % [37.5-98.9] for non-syndromic children. Among all surgical techniques, for syndromic and non-syndromic children, 54.8 % [30.9-77.5] and 73.9 % [61.3-84.6] obtained normal resonance post-operatively, respectively. Syndromic patients obtained normal resonance post-operatively in 83.3 % [57.7-96.6] of Combined Furlow Palatoplasty and Sphincter Pharyngoplasty (CPSP), 72.6 % [54.5-87.5] of Pharyngeal Flap (PF), and 45.1 % [13.2-79.8] of Sphincter Pharyngoplasty (SP) surgeries. Non-syndromic patients obtained normal resonance post-operatively in 79.2 % [66.4-88.8] of PF and 75.2 % [61.8-86.5] of SP surgeries. The revision rate for syndromic and non-syndromic patients was 19.9 % [15.0-25.6] and 11.3 % [5.8-18.3], respectively. The difference was statistically significant, 8.6 % [2.9-15.0, p = 0.003]. Syndromic patients who underwent PF were least likely to undergo revision surgery as compared to SP and CPSP, 7.7 % [2.3-17.9] vs. 23.7 % [15.5-33.1] and 15.3 % [2.8-40.7], respectively., Conclusions: Syndromic children had higher revision rates and were significantly less likely to obtain normal resonance following primary surgery than non-syndromic patients. Among syndromic children, PF and CPSP have been shown to improve resonance and reduce revision rates more so than SP alone., Competing Interests: Declaration of competing interest The authors have no conflict of interest to disclose., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: Meniere's Disease is a condition known for its recurrent vertigo, fluctuating sensorineural hearing loss, aural fullness, and tinnitus. Previous studies have demonstrated significant influence of placebo treatments. Our objective was to quantify the magnitude of the placebo effect in randomized controlled trials for Meniere's Disease., Materials and Methods: A systematic review was performed by searching PubMed, SCOPUS, CINAHL, and Cochrane databases from inception through September 27, 2022. Data extraction, quality rating, and risk of bias assessment were performed by two independent reviewers. A meta-analysis of mean differences with 95 % confidence interval, weighted summary proportions, and proportion differences were calculated using random and fixed effects models., Results: A total of 15 studies (N = 892) were included in the review. Significant improvement was seen in the functional level scores of the pooled placebo groups, with a mean difference of -0.6 points, (95%CI: -1.2 to -0.1). There was no difference in pure tone audiometry, speech discrimination score, or vertigo frequency at 1 and 3 months for the placebo group. Patient-reported vertigo episodes were improved in 52.5 % (95%CI: 39.2 to 65.5) of the placebo group and was significantly less than the pooled experimental group (90.1 %, 95%CI: 39.2 to 65.5, p < 0.001)., Conclusions: The placebo effect in Meniere's Disease trials is associated with some symptomatic improvement in subjective outcomes, such as patient reported vertigo episodes. However, the clinical significance is questionable across other outcomes measures, especially when analyzing objective data. The extent and strength of the placebo effect continues to be a hurdle in the search for better treatment options., Competing Interests: Declaration of competing interest The authors have no conflict of interest to disclose., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Key Points: The pandemic caused an increase in computed tomography imaging in patients with sinusitis, which persisted post-COVID. Nasal endoscopies significantly decreased during COVID but returned to pre-COVID levels in 2022. The management of cerebrospinal fluid leaks, tumors, and orbital pathology was not impacted by the pandemic., (© 2023 ARS-AAOA, LLC.)

Although HPV status is known to provide an improved prognosis in initial treatments of HPV-positive oropharyngeal squamous cell carcinoma (OPSCC), it is unclear how it affects patients who receive salvage surgery (SS), which has historically poor survival rates. The purpose of this study was to evaluate the role of SS for patients with locoregional recurrence (LRR) of HPV-positive OPSCC and its impact survival rates. We conducted a scoping review of literature through October 2022 and included 995 individuals. Survival endpoints, such as overall survival (OS), Kaplan-Meier curves, and median post-recurrence survival, were analyzed in addition to demographics. Of all studies, 18.8% (6/32) reported any survival data for SS patients, with the most prevalent reporting 2- and 5-year OS in two studies. Median post-recurrence survival was not reported for SS. These findings reveal the limited and unpredictable reporting of survival-specific data on SS for HPV-positive OPSCC. With limited survival assessment, it is difficult to assess the potential advantages and disadvantages of this therapy to guide clinical decision-making.

In patients receiving treatment for head and neck cancer (HNC), there is a correlation between quality of life (QoL) scores and treatment outcomes. Higher QoL scores have been associated with improved survival. Despite this, the assessment of QoL in clinical trials varies considerably. Three databases (Scopus, PubMed, and Cinahl) were queried for articles published in English between 2006 and 2022. Two reviewers (SRS and ANT) performed study screening, data extraction, and risk of bias assessment. The authors identified 21 articles that met the inclusion criteria. A total of 5961 patients were evaluated. QoL was reported as average scores for specific variables across five different surveys in 12 included articles. Supplemental QoL data were available in 10 included studies. Critical appraisal of studies indicated a high risk of bias due to the inclusion of trials. There is no standard method for reporting QoL data in clinical trials for HNC patients undergoing treatment with anti-EGFR inhibitors. Future clinical trials should standardize their method for assessing and reporting quality-of-life data to increase patient-centered care and refine treatment choices to optimize survival.

Importance: Whole-brain radiation therapy (WBRT) delivers a substantial radiation dose to the parotid glands, but the parotid glands are not delineated for avoidance and xerostomia has never been reported as an adverse effect. Minimizing the toxic effects in patients receiving palliative treatments, such as WBRT, is crucial., Objective: To assess whether xerostomia is a toxic effect of WBRT., Design, Setting, and Participants: This observational cohort study enrolled patients from November 2, 2015, to March 20, 2018, at 1 academic center (University of North Carolina Hospitals) and 2 affiliated community hospitals (High Point Regional Hospital and University of North Carolina Rex Hospital). Adult patients (n = 100) receiving WBRT for the treatment or prophylaxis of brain metastases were enrolled. Patients who had substantial baseline xerostomia or did not complete WBRT or at least 1 postbaseline questionnaire were prospectively excluded from analysis and follow-up. Patients received 3-dimensional WBRT using opposed lateral fields covering the skull and the C1 or C2 vertebra. Per standard practice, the parotid glands were not prospectively delineated., Main Outcomes and Measures: Patients completed the University of Michigan Xerostomia Questionnaire and a 4-point bother score at baseline, immediately after WBRT, at 1 month, at 3 months, and at 6 months. The primary end point was the 1-month xerostomia score, with a hypothesized worsening score of 10 points from baseline., Results: Of the 100 patients enrolled, 73 (73%) were eligible for analysis and 55 (55%) were evaluable at 1 month. The 73 patients included 43 women (59%) and 30 men (41%) with a median (range) age of 61 (23-88) years. The median volume of parotid receiving at least 20 Gy (V20Gy) was 47%. The mean xerostomia score was 7 points at baseline and was statistically significantly higher at each assessment period, including 21 points immediately after WBRT (95% CI, 16-26; P < .001), 23 points (95% CI, 16-30; P < .001) at 1 month, 21 points (95% CI, 13-28; P < .001) at 3 months, and 14 points (95% CI, 7-21; P = .03) at 6 months. At 1 month, the xerostomia score increased by 20 points or more in 19 patients (35%). The xerostomia score at 1 month was associated with parotid dose as a continuous variable and was 35 points in patients with parotid V20Gy of 47% or greater, compared with only 9 points in patients with parotid V20Gy less than 47% (P < .001). The proportion of patients who self-reported to be bothered quite a bit or bothered very much by xerostomia at 1 month was 50% in those with parotid V20Gy of 47% or greater, compared with only 4% in those with parotid V20Gy less than 47% (P < .001). At 3 months, this difference was 50% vs 0% (P = .001). Xerostomia was not associated with medication use., Conclusions and Relevance: Clinically significant xerostomia occurred by the end of WBRT, appeared to be persistent, and appeared to be associated with parotid dose. The findings from this study suggest that the parotid glands should be delineated for avoidance to minimize these toxic effects in patients who undergo WBRT and often do not survive long enough for salivary recovery.

X-ray microprobes (XRM) coupled with high-brightness synchrotron X-ray facilities are powerful tools for environmental biogeochemistry research. One such instrument, the XRM at the Geo Soil Enviro Center for Advanced Radiation Sources Sector 13 at the Advanced Photon Source (APS; Argonne National Laboratory, Lemont, IL) was recently improved as part of a canted undulator geometry upgrade of the insertion device port, effectively doubling the available undulator beam time and extending the operating energy of the branch supporting the XRM down to the sulfur K edge (2.3 keV). Capabilities include rapid, high-resolution, elemental imaging including fluorescence microtomography, microscale X-ray absorption fine structure spectroscopy including sulfur K edge capability, and microscale X-ray diffraction. These capabilities are advantageous for (i) two-dimensional elemental mapping of relatively large samples at high resolution, with the dwell times typically limited only by the count times needed to obtain usable counting statistics for low concentration elements, (ii) three-dimensional imaging of internal elemental distributions in fragile hydrated specimens, such as biological tissues, avoiding the need for physical slicing, (iii) spatially resolved speciation determinations of contaminants in environmental materials, and (iv) identification of contaminant host phases. In this paper, we describe the XRM instrumentation, techniques, applications demonstrating these capabilities, and prospects for further improvements associated with the proposed upgrade of the APS., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Miller Range (MIL) 090340 and MIL 090206 are olivine-rich achondrites originally classified as ureilites. We investigate their petrography, mineral compositions, olivine Cr valences, equilibration temperatures, and (for MIL 090340) oxygen isotope compositions, and compare them with ureilites and other olivine-rich achondrites. We conclude that they are brachinite-like achondrites that provide new insights into the petrogenesis of brachinite clan meteorites. MIL 090340,6 has a granoblastic texture and consists of ~97 modal % by area olivine (Fo = molar Mg/[Mg+Fe] = 71.3±0.6). It also contains minor to trace augite, chromite, chlorapatite, orthopyroxene, metal, troilite, and terrestrial Fe-oxides. Approximately 80% by area of MIL 090206,5 has a granoblastic texture of olivine (Fo 72.3±0.1) plus minor augite and chromite, similar to MIL 090340 but also containing minor plagioclase. The rest of the section consists of a single crystal of orthopyroxene (~11×3 mm), poikilitically enclosing rounded grains of olivine (Fo = 76.1±0.6), augite, chromite, metal and sulfide. Equilibration temperatures for MIL 090340 and MIL 090206, calculated from olivine-spinel, olivine-augite, and two-pyroxene thermometry range from ~800-930°C. In both samples, symplectic intergrowths of Ca-poor orthopyroxene + opaque phases (Fe-oxides, sulfide, metal) occur as rims on and veins/patches within olivine. Before terrestrial weathering, the opaques were probably mostly sulfide, with minor metal. All petrologic properties of MIL 090340 and MIL 090206 are consistent with those of brachinite clan meteorites, and largely distinct from those of ureilites. Oxygen isotope compositions of olivine in MIL 090340 (δ 18 O = 5.08±0.30‰, δ 17 O = 2.44±0.21‰, and Δ 17 O = -0.20±0.12‰) are also within the range of brachinite clan meteorites, and well distinguished from ureilites. Olivine Cr valences in MIL 090340 and the granoblastic area of MIL 090206 are 2.57±0.06 and 2.59±0.07, respectively, similar to those of three brachinites also analyzed here (Brachina, Hughes 026, Nova 003). They are higher than those of olivine in ureilites, even those containing chromite. The valence systematics of MIL 090340, MIL 090206, and the three analyzed brachinites (lower Fo = more oxidized Cr) are consistent with previous evidence that brachinite-like parent bodies were inherently more oxidized than the ureilite parent body. The symplectic orthopyroxene + sulfide/metal assemblages in MIL 090340, MIL 090206, and many brachinite clan meteorites have superficial similarities to characteristic "reduction rims" in ureilites. However, they differ significantly in detail. They likely formed by reaction of olivine with S-rich fluids, with only minor reduction. MIL 090340 and the granoblastic area of MIL 090206 are similar in modal mineralogy and texture to most brachinites, but have higher Fo values typical of brachinite-like achondrites. The poiklitic pyroxene area of MIL 090206 is more typical of brachinite-like achondrites. The majority of their properties suggest that MIL 090340 and MIL 090206 are residues of low-degree partial melting. The poikilitic area of MIL 090206 could be a result of limited melt migration, with trapping and recrystallization of a small volume of melt in the residual matrix. These two samples are so similar in mineral compositions, Cr valence, and cosmic ray exposure ages that they could be derived from the same lithologic unit on a common parent body.

Pollutants in acid mine drainage (AMD) are usually sequestered in neoformed nano- and micro-scale particles (nNP) through precipitation, co-precipitation, and sorption. Subsequent biogeochemical processes may control nNP stability and thus long-term contaminant immobilization. Mineralogical, chemical, and microbiological data collected from sediments accumulated over a six-year period in a coal-mine AMD treatment system were used to identify the pathways of contaminant dynamics. We present evidence that detrital nano- and micron-scale particles (dNP), composed mostly of clay minerals originating from the partial weathering of coal-mine waste, mediated biogeochemical processes that catalyzed AMD contaminant (1) immobilization by facilitating heterogeneous nucleation and growth of nNP in oxic zones, and (2) remobilization by promoting phase transformation and reductive dissolution of nNP in anoxic zones. We found that dNP were relatively stable under acidic conditions and estimated a dNP content of ~0.1g/L in the influent AMD. In the AMD sediments, the initial nNP precipitates were schwertmannite and poorly crystalline goethite, which transformed to well-crystallized goethite, the primary nNP repository. Subsequent reductive dissolution of nNP resulted in the remobilization of up to 98% of S and 95% of Fe accompanied by the formation of a compact dNP layer. Effective treatment of pollutants could be enhanced by better understanding the complex, dynamic role dNP play in mediating biogeochemical processes and contaminant dynamics at coal-mine impacted sites., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Heating a mixture of uranyl(vi) nitrate and tantalum(v) oxide in the molar ratio of 2 : 3 to 1400 °C resulted in the formation of a new compound, UTa 3 O 10 . The honey colored to yellow brown crystals of UTa 3 O 10 crystallize in an orthorhombic structure with the space group Fddd (no. 70), lattice parameters a = 7.3947(1), b = 12.7599(2), c = 15.8156(2) Å, and Z = 8. Vertex sharing [TaO 6 ] 7- octahedra of two crystallographically distinct Ta cations form a three dimensional tantalate framework. Within this framework, six membered rings of [TaO 6 ] 7- octahedra are formed within the (001) plane. The center of these rings is occupied by the uranyl cations [UO 2 ] + , with an oxidation state of +5 for uranium. The pentavalence of U and Ta was confirmed by X-ray photoelectron spectroscopy and X-ray adsorption spectroscopy. The enthalpy of formation of UTa 3 O 10 from Ta 2 O 5 , β-U 3 O 7 , and U 3 O 8 has been determined to be 13.1 ± 18.1 kJ mol -1 using high temperature oxide melt solution calorimetry with sodium molybdate as the solvent at 700 °C. The close to zero enthalpy of formation of UTa 3 O 10 can be explained by closely balanced structural stabilizing and destabilizing factors, which may also apply to other UM 3 O 10 compounds.

Supereruptions catastrophically eject 100s-1000s of km3 of magma to the surface in a matter of days to a few months. In this study, we use zoning in quartz crystals from the Bishop Tuff (California) to assess the timescales over which a giant magma body transitions from relatively quiescent, pre-eruptive crystallization to rapid decompression and eruption. Quartz crystals in the Bishop Tuff have distinctive rims (<200 μm thick), which are Ti-rich and bright in cathodoluminescence (CL) images, and which can be used to calculate Ti diffusional relaxation times. We use synchrotron-based x-ray microfluorescence to obtain quantitative Ti maps and profiles along rim-interior contacts in quartz at resolutions of 1-5 μm in each linear dimension. We perform CL imaging on a scanning electron microscope (SEM) using a low-energy (5 kV) incident beam to characterize these contacts in high resolution (<1 μm in linear dimensions). Quartz growth times were determined using a 1D model for Ti diffusion, assuming initial step functions. Minimum quartz growth rates were calculated using these calculated growth times and measured rim thicknesses. Maximum rim growth times span from ~1 min to 35 years, with a median of ~4 days. More than 70% of rim growth times are less than 1 year, showing that quartz rims have mostly grown in the days to months prior to eruption. Minimum growth rates show distinct modes between 10-8 and 10-10 m/s (depending on sample), revealing very fast crystal growth rates (100s of nm to 10s of μm per day). Our data show that quartz rims grew well within a year of eruption, with most of the growth happening in the weeks or days preceding eruption. Growth took place under conditions of high supersaturation, suggesting that rim growth marks the onset of decompression and the transition from pre-eruptive to syn-eruptive conditions.

Although pentavalent uranium can exist in aqueous solution, its presence in the solid state is uncommon. Metal monouranates, MgUO4, CrUO4 and FeUO4 were synthesized for detailed structural and energetic investigations. Structural characteristics of these uranates used powder X-ray diffraction, synchrotron X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and (57)Fe-Mössbauer spectroscopy. Enthalpies of formation were measured by high temperature oxide melt solution calorimetry. Density functional theory (DFT) calculations provided both structural and energetic information. The measured structural and thermodynamic properties show good consistency with those predicted from DFT. The presence of U(5+) has been solidly confirmed in CrUO4 and FeUO4, which are thermodynamically stable compounds, and the origin and stability of U(5+) in the system was elaborated by DFT. The structural and thermodynamic behaviour of U(5+) elucidated in this work is relevant to fundamental actinide redox chemistry and to applications in the nuclear industry and radioactive waste disposal.

The garnet structure has been proposed as a potential crystalline nuclear waste form for accommodation of actinide elements, especially uranium (U). In this study, yttrium iron garnet (YIG) as a model garnet host was studied for the incorporation of U analogs, cerium (Ce) and thorium (Th), incorporated by a charge-coupled substitution with calcium (Ca) for yttrium (Y) in YIG, namely, 2Y(3+) = Ca(2+) + M(4+), where M(4+) = Ce(4+) or Th(4+). Single-phase garnets Y3-xCa0.5xM0.5xFe5O12 (x = 0.1-0.7) were synthesized by the citrate-nitrate combustion method. Ce was confirmed to be tetravalent by X-ray absorption spectroscopy and X-ray photoelectron spectroscopy. X-ray diffraction and (57)Fe-Mössbauer spectroscopy indicated that M(4+) and Ca(2+) cations are restricted to the c site, and the local environments of both the tetrahedral and the octahedral Fe(3+) are systematically affected by the extent of substitution. The charge-coupled substitution has advantages in incorporating Ce/Th and in stabilizing the substituted phases compared to a single substitution strategy. Enthalpies of formation of garnets were obtained by high temperature oxide melt solution calorimetry, and the enthalpies of substitution of Ce and Th were determined. The thermodynamic analysis demonstrates that the substituted garnets are entropically rather than energetically stabilized. This suggests that such garnets may form and persist in repositories at high temperature but might decompose near room temperature.

Background: A nationwide outbreak of fungal infections was traced to injection of Exserohilum-contaminated methylprednisolone. We describe our experience with patients who developed spinal or paraspinal infection after injection of contaminated methylprednisolone., Methods: Data were assembled from the Michigan Department of Community Health, electronic medical records, and magnetic resonance imaging (MRI) reports., Results: Of 544 patients who received an epidural injection from a contaminated lot of methylprednisolone at a pain clinic in southeastern Michigan, 153 (28%) were diagnosed at our institution with probable or confirmed spinal or paraspinal fungal infection at the injection site. Forty-one patients had both meningitis and spinal or paraspinal infection, and 112 had only spinal or paraspinal infection. Magnetic resonance imaging abnormalities included abscess, phlegmon, arachnoiditis, and osteomyelitis. Surgical debridement in 116 patients revealed epidural phlegmon and epidural abscess most often. Among 26 patients with an abnormal MRI but with no increase or change in chronic pain, 19 (73%) had infection identified at surgery. Fungal infection was confirmed in 78 patients (51%) by finding hyphae in tissues, positive polymerase chain reaction, or culture. Initial therapy was voriconazole plus liposomal amphotericin B in 115 patients (75%) and voriconazole alone in 38 patients (25%). As of January 31, 2014, 20 patients remained on an azole agent. Five patients died of infection., Conclusions: We report on 153 patients who had spinal or paraspinal fungal infection at the site of epidural injection of contaminated methylprednisolone. One hundred sixteen (76%) underwent operative debridement in addition to treatment with antifungal agents.

The structural behavior of GeO2 glass has been investigated up to 64 GPa using results from x-ray absorption spectroscopy in a diamond anvil cell combined with previously reported density measurements. The difference between the nearest Ge-O distances of glassy and rutile-type GeO2 disappears at the Ge-O distance maximum at 20 GPa, indicating completion of the tetrahedral-octahedral transition in GeO2 glass. The mean-square displacement σ(2) of the Ge-O distance in the first Ge-O shell increases progressively to a maximum at 10 GPa, followed by a substantial reduction at higher pressures. The octahedral glass is, as expected, less dense and has a higher compressibility than the corresponding crystalline phase, but the differences in Ge-O distance and density between the glass and the crystals are gradually eliminated over the 20-40 GPa pressure range. Above 40 GPa, GeO2 forms a dense octahedral glass with a compressibility similar to that of the corresponding crystalline phase (α-PbO2 type). The EXAFS and XANES spectra show evidence for subtle changes in the dense glass continuing to occur at these high pressures. The Ge-O bond distance shows little change between 45-64 GPa, and this may reflect a balance between bond shortening and a gradual coordination number increase with compression. The density of the glass is similar to that of the α-PbO2-type phase, but the Ge-O distance is longer and is close to that in the higher-coordination pyrite-type phase which is stable above ∼60 GPa. The density data provide evidence for a possible discontinuity and change in compressibility at 40-45 GPa, but there are no major changes in the corresponding EXAFS spectra. A pyrite-type local structural model for the glass can provide a reasonable fitting to the XAFS spectra at 64 GPa.

A defining characteristic of silicate melts is the degree of polymerization (tetrahedral connectivity), which dictates viscosity and affects compressibility. While viscosity of depolymerized silicate melts increases with pressure consistent with the free-volume theory, isothermal viscosity of polymerized melts decreases with pressure up to ~3-5 GPa, above which it turns over to normal (positive) pressure dependence. Here we show that the viscosity turnover in polymerized liquids corresponds to the tetrahedral packing limit, below which the structure is compressed through tightening of the inter-tetrahedral bond angle, resulting in high compressibility, continual breakup of tetrahedral connectivity and viscosity decrease with increasing pressure. Above the turnover pressure, silicon and aluminium coordination increases to allow further packing, with increasing viscosity and density. These structural responses prescribe the distribution of melt viscosity and density with depth and play an important role in magma transport in terrestrial planetary interiors.

Objectives: This report presents new data from birth certificates on the principal source of payment for the delivery in 2010 for the following groups: private insurance, Medicaid, self-pay (uninsured), and other payment sources. These data are for the 33 states and District of Columbia that adopted the 2003 U.S. Standard Certificate of Live Birth by January 2010, representing 76% of all 2010 U.S. births. Trend data for the United States for 1990-2010 are also presented from the Centers for Disease Control and Prevention's National Center for Health Statistics, National Hospital Discharge Survey (NHDS), to provide a national comparison and historical context., Methods: Tabular and graphical data on deliveries by the principal source of payment for 2010 from the birth certificate are compared with NHDS estimates. Trend data for 1990-2010 from NHDS are also presented. Detailed data from the birth certificate on maternal characteristics, prenatal care receipt, and cesarean delivery are provided., Results: Private insurance was the most frequent payment source for deliveries in the birth certificate-revised reporting area in 2010 (45.8% of births), followed closely by Medicaid (44.9%), ''other'' payment sources (5.0%), and self-pay (4.4%). Similarly, NHDS data show that private insurance was the most common payment source for deliveries nationally in 2010, followed by Medicaid. Privately insured deliveries declined over the last decade, while the use of Medicaid insurance increased. Medicaid insurance of deliveries was highest for births to teenagers and for non-Hispanic black and Hispanic mothers, according to the birth certificate data. Privately insured mothers were most likely of all payment groups to receive early prenatal care and to have cesarean deliveries., (All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.)

Objectives: A primary goal of the 2003 revision of the U.S. Standard Certificate of Live Birth was to improve data quality, in part by improving data sources, definitions, and instructions. This report evaluates the quality of selected medical and health data from the 2003 revision of the birth certificate by comparing birth certificate data with information abstracted from hospital medical records., Methods: A random sample of records for 600 births that occurred in 2010-2011 in State A, and a convenience sample of 495 births that occurred in State B in 2009 were reviewed. Birth certificate and hospital medical record data were compared for these categories: pregnancy history, prenatal care, gestational age, birthweight, pregnancy risk factors, obstetric procedures, onset of labor, source of payment, characteristics of labor and delivery, fetal presentation, method of delivery, abnormal conditions of the newborn, infant living, and infant breastfed. Levels of missing data, exact agreement, kappa scores, sensitivity, and false discovery rates are presented, where applicable., Results: Exact agreement or sensitivity, was high for a number of items for both states (e.g., number of cesarean deliveries, cephalic presentation, cesarean delivery, and birthweight within 500 grams), but exact agreement or sensitivity was low or extremely low for both states for several items (e.g., total number of prenatal visits, previous preterm birth, meconium staining, and fetal intolerance of labor) (Figure 1). Levels of agreement or sensitivity for most items (e.g., prenatal care beginning in first trimester and source of payment-private insurance) were substantial or moderate. Data quality varied by state, and often, varied widely by hospital.

Objectives: When a health problem is perceived as having a genetic cause, this appears to increase the perceived effectiveness of pharmacological treatments and reduce perceived effectiveness of non-pharmacological treatments. Potential mediators of this effect include causal attributions, perceived severity, and perceived control over the health problem. This study aimed to use experimental methods to establish which beliefs mediate the effect of genetic causal information on perceived effectiveness of treatments., Design: A 4(cause: environmental, family history, genetic test, family history & genetic test)×2(severity: higher or low) between-subjects design using vignettes about heart disease risk, obesity or depression., Methods: A total of 647 adults, randomly assigned to read one of the experimental vignettes, were interviewed. Key outcomes were perceived effectiveness of medication and of non-pharmacological treatments. Potential mediators of perceived severity, perceived controllability, and causal attributions were also assessed., Results: For heart disease risk, genetic causes reduced perceived effectiveness of non-pharmacological treatments (an effect mediated by causal attributions and perceived control) but did not influence perceived medication effectiveness. For obesity, neither severity nor cause influenced the perceived effectiveness of either treatment. For depression, genetic causes only increased perceived effectiveness of medication for more severe depression, an effect mediated by perceived control., Conclusions: The impact of genetic causal information on perceived effectiveness of treatments varies with type of health problem. When genetic causal information influences perceived treatment effectiveness, it does so by altering causal attributions and perceived controllability. However, these effects are small and unlikely to translate into clinically meaningful differences in health-enhancing behaviours., (©2011 The British Psychological Society.)

Objectives: To describe the characteristics of a sample of smokers recruited proactively into a smoking cessation trial, and to compare these characteristics with the wider population using data from the General Household Survey (GHS) and National Statistics Omnibus Survey., Study Design: Sample recruited for a randomized controlled trial., Methods: Between August 2007 and October 2008, 123 general practices mailed questionnaires to smokers in the U.K. identified from computer records. Smokers willing to participate in a trial of personalized computer-tailored feedback returned the questionnaires to the research team. The characteristics of the sample were compared with the wider population using data from the GHS and National Statistics Omnibus Survey, and Index of Material Deprivation scores., Results: A response rate of 11.4% (n = 6697) was achieved. The sample was demographically similar to the population sample, with an even distribution of participants from areas of both high and low deprivation. The sample was more dependent than the GHS sample, but less dependent than clinic samples. Distribution by motivation and readiness to quit was similar to population estimates., Conclusions: Public health strategies targeting the entire population of smokers are needed to counter the low recruitment rates resulting from the traditional reactive methods of recruitment to smoking cessation studies. Using computerized records to identify and contact patients who are smokers is a simple method of recruiting a larger, more representative sample of smokers., (Copyright © 2011 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)

Supereruptions violently transfer huge amounts (100 s-1000 s km(3)) of magma to the surface in a matter of days and testify to the existence of giant pools of magma at depth. The longevity of these giant magma bodies is of significant scientific and societal interest. Radiometric data on whole rocks, glasses, feldspar and zircon crystals have been used to suggest that the Bishop Tuff giant magma body, which erupted ~760,000 years ago and created the Long Valley caldera (California), was long-lived (>100,000 years) and evolved rather slowly. In this work, we present four lines of evidence to constrain the timescales of crystallization of the Bishop magma body: (1) quartz residence times based on diffusional relaxation of Ti profiles, (2) quartz residence times based on the kinetics of faceting of melt inclusions, (3) quartz and feldspar crystallization times derived using quartz+feldspar crystal size distributions, and (4) timescales of cooling and crystallization based on thermodynamic and heat flow modeling. All of our estimates suggest quartz crystallization on timescales of <10,000 years, more typically within 500-3,000 years before eruption. We conclude that large-volume, crystal-poor magma bodies are ephemeral features that, once established, evolve on millennial timescales. We also suggest that zircon crystals, rather than recording the timescales of crystallization of a large pool of crystal-poor magma, record the extended periods of time necessary for maturation of the crust and establishment of these giant magma bodies.

Phases of the iron-oxygen binary system are significant to most scientific disciplines, directly affecting planetary evolution, life, and technology. Iron oxides have unique electronic properties and strongly interact with the environment, particularly through redox reactions. The iron-oxygen phase diagram therefore has been among the most thoroughly investigated, yet it still holds striking findings. Here, we report the discovery of an iron oxide with formula Fe(4)O(5), synthesized at high pressure and temperature. The previously undescribed phase, stable from 5 to at least 30 GPa, is recoverable to ambient conditions. First-principles calculations confirm that the iron oxide here described is energetically more stable than FeO + Fe(3)O(4) at pressure greater than 10 GPa. The calculated lattice constants, equation of states, and atomic coordinates are in excellent agreement with experimental data, confirming the synthesis of Fe(4)O(5). Given the conditions of stability and its composition, Fe(4)O(5) is a plausible accessory mineral of the Earth's upper mantle. The phase has strong ferrimagnetic character comparable to magnetite. The ability to synthesize the material at accessible conditions and recover it at ambient conditions, along with its physical properties, suggests a potential interest in Fe(4)O(5) for technological applications.

Arsenic is naturally associated with gold mineralisation and elevated in some soils and mine waste around historical gold mining activity in Victoria, Australia. To explore uptake, arsenic concentrations in children's toenail clippings and household soils were measured, and the microdistribution and speciation of arsenic in situ in toenail clipping thin sections investigated using synchrotron-based X-ray microprobe techniques. The ability to differentiate exogenous arsenic was explored by investigating surface contamination on cleaned clippings using depth profiling, and direct diffusion of arsenic into incubated clippings. Total arsenic concentrations ranged from 0.15 to 2.1 microg/g (n=29) in clipping samples and from 3.3 to 130 microg/g (n=22) in household soils, with significant correlation between transformed arsenic concentrations (Pearson's r=0.42, P=0.023) when household soil was treated as independent. In clipping thin sections (n=2), X-ray fluorescence (XRF) mapping showed discrete layering of arsenic consistent with nail structure, and irregular arsenic incorporation along the nail growth axis. Arsenic concentrations were heterogeneous at 10x10 microm microprobe spot locations investigated (<0.1 to 13.3 microg/g). X-ray absorption near-edge structure (XANES) spectra suggested the presence of two distinct arsenic species: a lower oxidation state species, possibly with mixed sulphur and methyl coordination (denoted As(approximately III)(-S, -CH3)); and a higher oxidation state species (denoted As(approximately V)(-O)). Depth profiling suggested that surface contamination was unlikely (n=4), and XRF and XANES analyses of thin sections of clippings incubated in dry or wet mine waste, or untreated, suggested direct diffusion of arsenic occurred under moist conditions. These findings suggest that arsenic in soil contributes to some systemic absorption associated with periodic exposures among children resident in areas of historic gold mining activity in Victoria, Australia. Future studies are required to ascertain if adverse health effects are associated with current levels of arsenic uptake., (Copyright 2010 Elsevier B.V. All rights reserved.)

A modified Drickamer anvil apparatus has been developed to combine with monochromatic synchrotron radiation for high-pressure X-ray diffraction and radiography in the GSECARS bending-magnet station, 13-BM-D, at the Advanced Photon Source, Argonne, USA. Using this experimental set-up, deformation experiments can be carried out at pressures in excess of 30 GPa at high temperatures. Differential stresses and total axial strains of polycrystalline platinum and Mg(2)SiO(4) ringwoodite have been measured up to 32 GPa at room temperature using tungsten carbide anvils. The total axial strain of the platinum increases with pressure and reaches about 55% at the highest pressure. A test run using a composite sintered diamond anvil system was performed. The use of X-ray-tranparent anvils enables the entire Debye rings to be observed up to 10 degrees 2theta. With high-energy photons (65-70 keV), this allows a coverage in Q (= 2pi sintheta/lambda) to about 3 A(-1), thus making it possible to evaluate hydrostatic pressure and differential stress in crystalline minerals using diffraction. This, coupled with the ability to determine axial strain, allows deformation studies to be performed to pressures above 30 GPa.

We describe an approach for acquiring high quality x-ray absorption fine structure (XAFS) spectroscopy spectra with wide energy range at high pressure using diamond anvil cell (DAC). Overcoming the serious interference of diamond Bragg peaks is essential for combining XAFS and DAC techniques in high pressure research, yet an effective method to obtain accurate XAFS spectrum free from DAC induced glitches has been lacking. It was found that these glitches, whose energy positions are very sensitive to the relative orientation between DAC and incident x-ray beam, can be effectively eliminated using an iterative algorithm based on repeated measurements over a small angular range of DAC orientation, e.g., within +/-3 degrees relative to the x-ray beam direction. Demonstration XAFS spectra are reported for rutile-type GeO2 recorded by traditional ambient pressure and high pressure DAC methods, showing similar quality at 440 eV above the absorption edge. Accurate XAFS spectra of GeO2 glass were obtained at high pressure up to 53 GPa, providing important insight into the structural polymorphism of GeO2 glass at high pressure. This method is expected be applicable for in situ XAFS measurements using a diamond anvil cell up to ultrahigh pressures.

The oxidation status of uranium in sediments is important because the solubility of this toxic and radioactive element is much greater for U(VI) than for U(IV) species. Thus, redox manipulation to promote precipitation of UO2 is receiving interest as a method to remediate U-contaminated sediments. Presence of Fe and Mn oxides in sediments at much higher concentrations than U requires an understanding of their redox status as well. This study was conducted to determine changes in oxidation states of U, Fe, and Mn in U-contaminated sediments from Oak Ridge National Laboratory. Oxidation states of these elements were measured in real-time and nondestructively using X-ray absorption spectroscopy on sediment columns supplied with synthetic groundwater containing organic carbon (OC, 0, 3, 10, 30, and 100 mM OC as lactate) for over 400 days. In sediments supplied with OC > or = 30 mM, 80% of the U was reduced to U(IV), with transient reoxidation at about 150 days. Mn(III,IV) oxides were completely reduced to Mn(II) in sediments infused with OC > or = 3 mM. However, Fe remained largely unreduced in all sediment columns, showing that Fe(III) can persist as an electron acceptor in reducing sediments over long times. This result in combination with the complete reduction of all other potential electron acceptors supports the hypothesis that the reactive Fe(III) fraction was responsible for reoxidizing U(IV).

US births increased 3% between 2005 and 2006 to 4,265,996, the largest number since 1961. The crude birth rate rose 1%, to 14.2 per 1000 population, and the general fertility rate increased 3%, to 68.5 per 1000 women 15 to 44 years. Births and birth rates increased among all race and Hispanic-origin groups. Teen childbearing rose 3% in 2006, to 41.9 per 1000 females aged 15 to 19 years, the first increase after 14 years of steady decline. Birth rates rose 2% to 4% for women aged 20 to 44; rates for the youngest (10-14 years) and oldest (45-49) women were unchanged. Childbearing by unmarried women increased steeply in 2006 and set new historic highs. The cesarean-delivery rate rose by 3% in 2006 to 31.1% of all births; this figure has been up 50% over the last decade. Preterm and low birth weight rates also increased for 2006 to 12.8% and 8.3%, respectively. The 2005 infant mortality rate was 6.89 infant deaths per 1000 live births, not statistically higher than the 2004 level. Non-Hispanic black newborns continued to be more than twice as likely as non-Hispanic white and Hispanic infants to die in the first year of life in 2004. For all gender and race groups combined, expectation of life at birth reached a record high of 77.9 years in 2005. Age-adjusted death rates in the United States continue to decline. The crude death rate for children aged 1 to 19 years decreased significantly between 2000 and 2005. Of the 10 leading causes of death for children in 2005, only the death rate for cerebrovascular disease was up slightly from 2000, whereas accident and chronic lower respiratory disease death rates decreased. A large proportion of childhood deaths, however, continue to occur as a result of preventable injuries.

We describe an x-ray absorption method for in situ density measurement of non-crystalline materials in the diamond anvil cell using a monochromatic synchrotron x-ray microbeam. Sample thickness, which is indispensable in the absorption method, can be determined precisely by extrapolating the thickness profile of the gasket obtained by x-ray absorption and diffraction measurements. Diamond deformation across the sample chamber becomes noticeable at high pressures above 10 GPa, which can be monitored with a precision better than 1%, as demonstrated by measurements on crystalline Ag. We have applied the developed method to measure densities of the classic network-forming GeO(2) glass in octahedral form at pressures up to 56 GPa. The fit to the pressure-volume data with the Birch-Murnaghan equation from 13 to 56 GPa gives parameters of V(0)=23.2+/-0.4 cm(3)mol and K=35.8+/-3.0 GPa, assuming that K(')=4. This method could be applicable for in situ determination of the density of liquids and other noncrystalline materials using a diamond anvil cell up to ultrahigh pressures.

In situ reduction of toxic Cr(VI) to less hazardous Cr(III) is becoming a popular strategy for remediating contaminated soils. However, the long-term stability of reduced Cr remains to be understood, especially given the common presence of Mn(III, IV) oxides that re-oxidize Cr(III). This 4.6 year laboratory study tracked Cr and Mn redox transformations in soils contaminated with Cr(VI), which were then treated with different amounts of organic carbon (OC). Changes in Cr and Mn oxidation states within soils were directly and nondestructively measured using micro-X-ray absorption near-edge structure spectroscopy. Chromate reduction was roughly first-order, and the extent of reduction was enhanced with higher OC additions. However, significant Cr(III) re-oxidation occurred in soils exposed to the highest Cr(VI) concentrations (2560 mg kg(-1)). Transient Cr(Ill) re-oxidation up to 420 mg kg(-1) was measured at 1.1 years after OC treatment, followed by further reduction. Chromate concentrations increased by 220 mg kg(-1) at the end of the study (4.6 years) in one soil. The causal role that the Mn oxidation state had in re-oxidizing Cr was supported by trends in Mn K-edge energies. These results provide strong evidence for long-term dependence of soil Cr oxidation states on balances between OC availability and Mn redox status.

We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.

The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.

Plutonium oxidation state distribution on Yucca Mountain tuff and synthetic pyrolusite (beta-MnO2) suspensions was measured using synchrotron X-ray micro-spectroscopy and microimaging techniques as well as ultrafiltration/solventextraction techniques. Plutonium sorbed to the tuff was preferentially associated with manganese oxides. For both Yucca Mountain tuff and synthetic pyrolusite, Pu(IV) or Pu(V) was initially oxidized to more mobile Pu(V/VI), but over time, the less mobile Pu(IV) became the predominant oxidation state of the sorbed Pu. The observed stability of Pu(IV) on oxidizing surfaces (e.g., pyrolusite), is proposed to be due to the formation of a stable hydrolyzed Pu(IV) surface species. These findings have important implications in estimating the risk associated with the geological burial of radiological waste in areas containing Mn-bearing minerals, such as at the Yucca Mountain or the Hanford Sites, because plutonium will be predominantly in a much less mobile oxidation state (i.e., Pu(IV)) than previously suggested (i.e., Pu(V/VI).

Research has shown that cancer patients in general benefit from support group participation. However, few patients attend such groups. This study investigated differences between participants of a community cancer support group and a random selection of non-participants from the Cancer Registry. Data were collected through mail survey, and included variables identified through past research and variables derived from Leventhal's self-regulatory model of illness representations and the theory of planned behaviour. Sixty-three support group participants and 44 comparison sample respondents were recruited. Support group participants were more likely to be female, without a partner, younger, and to have more education and formal support than non-participants. They held more favourable views of support groups, believed that significant others were favourable towards participation, and perceived less difficulty in joining a group. They furthermore used more active, adaptive coping strategies and felt more control over their cancer, but were more distressed and anxious. Non-participants reported more support from a special person. A multivariate logistic regression analysis showed only psychosocial variables to be independent predictors of participation. As psychological variables are amenable to change, increase of appropriate support group participation should be possible, for instance by addressing patients' beliefs about support groups., ((c) 2005 John Wiley & Sons, Ltd.)

The arsenic (As) solid-state speciation (i.e., oxidation state, precipitates, and adsorption complexes) is one of the most important factors controlling dissolved As concentrations at As contaminated sites. In this case study, two representative subsurface samples (i.e., oxidized and semi-reduced sites) from former lead arsenate contaminated soils in the northeastern United States were chosen to investigate the effects of aging on As retention mechanisms using multiscale spectroscopic techniques. X-ray powder diffraction (XRD), synchrotron based microfocused (micro) XRD, in situ micro-synchrotron based X-ray fluorescence spectroscopy (SXRF), and micro-X-ray absorption near edge structure (XANES) spectroscopy were used to compliment the final bulk X-ray absorption spectroscopy (XAS) analyses. In the sample from an oxic area, As is predominantly (approximately 71%) present as As(V) adsorbed onto amorphous iron oxyhydroxides with a residue (approximately 29%) of an original contaminant, schultenite (PbHAsO4). Contrarily, there is no trace of schultenite in the sample from a semi-reduced area. Approximately 25% of the total As is present as adsorbed phases on amorphous iron oxyhydroxide and amorphous orpiment (As2S3). The rest of the fractions (approximately 46%) were identified as As(V)-Ca coprecipitates. This study shows that aging effects can significantly alter the original chemical constituent (schultenite) in soils, resulting in multi and site-specific As solid-state speciation. The variability in spatial and temporal scale may be important in assessing the environmental risk and in developing in situ remediation technologies.

Micro-X-ray fluorescence (micro-XRF) microprobe analysis and micro-X-ray absorption near-edge structure (micro-XANES) spectroscopy were employed to identify Fe and Mn phases and their association with selected metals in two biosolids (limed composted [LC] and Nu-Earth) before and after treatment to remove organic carbon (OC). Spatial correlations derived from elemental mapping of XRF images showed strong correlations between Fe and Cd, Cr, Pb, or Zn (r2= 0.65-0.92) before and after removal of most of the OC. The strong correlation between Fe and Cu that was present in intact samples disappeared after OC removal, suggesting that Cu was associated with OC coatings that may have been present on Fe compounds. Except for Fe and Cr, the spatial correlations of metals with Mn were improved after treatment to remove OC, indicating that the treatment may have altered more than the OC in the system. The Fe micro-XANES spectra of the intact biosolids sample showed that every point had varying mixtures of Fe(II and III) species and no two points were identical. The lack of uniformity in Fe species in the biosolids sample illustrates the complexity of the materials and the difficulty of studying biosolids using conventional analytical tools or chemical extraction techniques. Still, these microscopic observations provide independent information supporting the previous laboratory and field hypothesis that Fe compounds play a major role in retention of environmentally important trace elements in biosolids. This could be due to co-precipitation of the metals with Fe, adsorption of metals by Fe compounds, or a combination of both mechanisms.

Arsenic is a contaminant in the groundwater of Holocene aquifers in Bangladesh, where approximately 57 million people drink water with arsenic levels exceeding the limits set by the World Health Organization. Although arsenic is native to the sediments, the means by which it is released to groundwater remains unresolved. Contrary to the current paradigm, ferric (hydr)oxides appear to dominate the partitioning of arsenic in the near surface but have a limited impact at aquifer depths where wells extract groundwater with high arsenic concentrations. We present a sequence of evidence that, taken together, suggest that arsenic may be released in the near surface and then transported to depth. We establish that (i) the only portion of the sediment profile with conditions destabilizing to arsenic in our analysis is in the surface or near-surface environment; (ii) a consistent input of arsenic via sediment deposition exists; (iii) retardation of arsenic transport is limited in the aquifers; and (iv) groundwater recharge occurs at a rate sufficient to necessitate continued input of arsenic to maintain observed concentrations. Our analyses thus lead to the premise that arsenic is liberated in surface and near-surface sediments through cyclic redox conditions and is subsequently transported to well depth. Influx of sediment and redox cycling provide a long-term source of arsenic that when liberated in the near surface is only weakly partitioned onto sediments deeper in the profile and is transported through aquifers by groundwater recharge.

Costly disposal of uranium (U) contaminated sediments is motivating research on in situ U(VI) reduction to insoluble U(IV) via directly or indirectly microbially mediated pathways. Delivery of organic carbon (OC) into sediments for stimulating U bioreduction is diffusion-limited in less permeable regions of the subsurface. To study OC-based U reduction in diffusion-limited regions, one slightly acidic and another calcareous sediment were treated with uranyl nitrate, packed into columns, then hydrostatically contacted with tryptic soy broth solutions. Redox potentials, U oxidation state, and microbial communities were well correlated. At average supply rates of 0.9 micromol OC (g sediment)(-1) day(-1), the U reduction zone extended to only about35-45 mm into sediments. The underlying unreduced U(VI) zone persisted over 600 days because the supply of OC was diffusion-limited and metabolized within a short distance. These results also suggestthat low U concentrations in groundwater samples from OC-treated sediments are not necessarily indicative of pervasive U reduction because interior and exterior regions of such sediment blocks can contain primarily U(VI) and U(IV), respectively.

An overview of facilities for high-pressure research with the diamond anvil cell (DAC) at the GeoSoilEnviroCARS (GSECARS) sector at the Advanced Photon Source (Argonne, Illinois) is presented. There are three operational experimental stations (13-ID-C, 13-ID-D and 13-BM-D) where DAC instrumentation is installed for various types of experiments at high pressure and extreme temperature conditions. A fourth station (13-BM-C) is under construction and will be operational in 2006. While most X-ray diffraction experiments have been undertaken with powder samples so far, there is a growing demand for single-crystal diffraction (SCD) at high pressure. As one of the principal components at GSECARS, SCD is currently under rapid development. Other relevant techniques have also been developed for obtaining complementary information from powder or single-crystal samples at high pressure. For example, an on-line Brillouin system is installed and operational at 13-BM-D for acoustic velocity and single-crystal elasticity determinations. In addition, various X-ray spectroscopy techniques (e.g. X-ray emission and X-ray Raman) are employed for measuring electronic and magnetic properties. Future developments are discussed with the DAC program at GSECARS.

The grain-size distribution and the character of individual grain boundaries in microcrystalline networks play a significant role in material properties, such as melting temperature, diffusion coefficients, resistivity, optical absorption, elastic constants, phase transformation pressure, and so on. In this study, the grain size of NaCl, SiO2 and FeC3 is controlled in situ at high pressures over the entire range of the length scale of crystallinity: single-crystal, micro-/nanocrystalline and amorphous materials within a volume commensurate with the size of the probing X-ray beam. The structure refinement of high-pressure samples from X-ray diffraction data can be significantly improved by controlling grain size by selecting the structure of starting materials and following certain high pressure-temperature-time paths.

Nuclear weapons and fuel production have left many soils and sediments contaminated with toxic levels of uranium (U). Although previous short-term experiments on microbially mediated U(VI) reduction have supported the prospect of immobilizing the toxic metal through formation of insoluble U(IV) minerals, our longer-term (17 months) laboratory study showed that microbial reduction of U can be transient, even under sustained reducing conditions. Uranium was reduced during the first 80 days, but later (100-500 days) reoxidized and solubilized, even though a microbial community capable of reducing U(VI) was sustained. Microbial respiration caused increases in (bi)-carbonate concentrations and formation of very stable uranyl carbonate complexes, thereby increasing the thermodynamic favorability of U(IV) oxidation. We propose that kinetic limitations including restricted mass transfer allowed Fe-(III) and possibly Mn(IV) to persist as terminal electron acceptors (TEAs) for U reoxidation. These results show that in-situ U remediation by organic carbon-based reductive precipitation can be problematic in sediments and groundwaters with neutral to alkaline pH, where uranyl carbonates are most stable.

Typha latifolia (cattail) sequesters arsenic within predominantlyferric iron root coatings, thus decreasing mobility of this toxic element in wetland sediments. Element-specific XRF microtomographic imaging illustrated a high spatial correlation between iron and arsenic in root plaques, with little arsenic in the interior of the roots. XANES analyses demonstrated that the plaque was predominantly ferric iron and contained approximately 20% As(III) and 80% As(V), which is significant because the two oxidation states form species that differ in toxicity and mobility. For the first time, spatial distribution maps of As oxidation states were developed, indicating that As(III) and As(V) are both fairly heterogeneous throughoutthe plaque. Chemical extractions showed that As was strongly adsorbed in the plaque rather than coprecipitated. Iron and arsenic concentrations ranged from 0.03 to 0.8 g Fe g(-1) wet plaque and 30 to 1200 microg As g(-1) wet plaque, consistent with a mechanism of As adsorption onto Fe(III) oxyhydroxide plaque. Because this mechanism decreases the concentrations of both As(III) and As(V) in groundwater, we propose that disruption of vegetation could increase the concentrations of mobile arsenic.

Uranium contamination of soils and sediments often originates from acidic or alkaline waste sources, with diffusion being a major transport mechanism. Measurements of U(VI) diffusion from initially pH 2 and pH 11 solutions into a slightly alkaline Altamont soil and a neutral Oak Ridge soil were obtained through monitoring uptake from boundary reservoirs and from U concentration profiles within soil columns. The soils provided pH buffering, resulting in diffusion at nearly constant pH. Micro X-ray absorption near edge structure spectra confirmed that U remained in U(VI) forms in all soils. Time trends of U(VI) depletion from reservoirs and U(VI) concentration profiles within soil columns yielded Kdvalues consistent with those determined in batch tests at similar concentrations (approximately 1 mM) and much lower than values for sorption at much lower concentrations (nM to microM). These results show that U(VI) transport at high concentrations can be relatively fast at non-neutral pH, with negligible surface diffusion, because of weak sorption.

We report structural data on liquid iron at pressures up to 58 GPa measured by x-ray scattering in a laser heated diamond anvil cell. The determined structure factor preserves essentially the same shape along the melting curve. Our data demonstrate that liquid iron at high pressures is a close-packed hard-sphere liquid. The results place important constraints on the thermodynamic and transport properties of liquid iron and the melting curve of iron.

Objectives: To examine the emotional and cognitive impact of personal and social comparison information about health risk., Methods: A total of 970 adults responded to vignettes describing risk presentation scenarios that varied in terms of having (a) a 'real world' analogue (cardiac event) versus no such analogue (a fictitious pancreatic disease) condition, (b) high versus low levels of personal risk, and (c) no comparison group information given, comparison group risk higher or lower than own risk., Results: For both the cardiac and pancreatic disease vignettes, respondents' emotional responses and estimates of their own risk were influenced by both personal and social comparison risk information. The cardiac event vignettes produced larger effects than the pancreatic disease vignettes. Unfavourable social comparison information had no discernible impact, relative to not providing any social comparison information. Favourable social comparison information resulted in greater reassurance, less worry, and perceptions of lower susceptibility. Lower personal risk generally produced similar effects, relative to higher personal risk., Conclusions: In contrast to previous theory and research in this area, we found that both personal and (favourable) social comparison risk information have emotional and cognitive consequences. We hypothesize that the perceived clarity of the information may account for the different patterns of findings in the literature.

Individual 1-3 mm biotite and muscovite clasts from Hanford sediment were contacted with 0.08 M CsNO3. They were examined using electron or X-ray microprobe methods, as intact specimens or sectioned perpendicular to their basal planes. Cs+ was observed to preferentially sorb to mica edges, steps on mica surfaces, or fractured regions. The localization of Cs conformed to hypothesized strong binding to frayed edge sites in preference to sites on basal planes. In section, Cs+ was found to penetrate the mica interior, forming discrete zones of concentration, particularly in muscovite. In biotite, Cs was more abundant, permeating the clasts, but also forming discrete zones of higher concentration. Concentrated Cs on both clast edges and within clast interiors corresponded to microscopic but relatively extensive zones where K was depleted. The localization of sorbed Cs in areas where K was depleted suggested that weathering reactions had caused the formation of frayed edge sites within the micas. Cs+ accessed crystal interiors by diffusion along channels following crystal defects, cracks, or partings where pore fluids had previously migrated to form the interior alteration zones. On the nanometer scale, areas with localized Cs were disrupted, confirming that frayed edge sites were developed in clast interiors.

Chromium has become an important soil contaminant at many sites, and facilitating in situ reduction of toxic Cr(VI) to nontoxic Cr(III) is becoming an attractive remediation strategy. Acceleration of Cr(VI) reduction in soils by addition of organic carbon was tested in columns pretreated with solutions containing 1000 and 10 000 mg L(-1) Cr(VI) to evaluate potential in situ remediation of highly contaminated soils. Solutions containing 0,800, or 4000 mg L(-1) organic carbon in the form of tryptic soy broth or lactate were diffused into the Cr(VI)-contaminated soils. Changes in Cr oxidation state were monitored through periodic micro-XANES analyses of soil columns. Effective first-order reduction rate constants ranged from 1.4 x 10(-8) to 1.5 x 10(-7) s(-1), with higher values obtained for lower levels of initial Cr(VI) and higher levels of organic carbon. Comparisons with sterile soils showed that microbially dependent processes were largely responsible for Cr(VI) reduction, except in the soils initially exposed to 10 000 mg L(-1) Cr(VI) solutions that receive little (800 mg L(-1)) or no organic carbon. However, the microbial populations (< or = 2.1 x 10(5) g(-1)) in the viable soils are probably too low for direct enzymatic Cr(VI) reduction to be important. Thus, synergistic effects sustained in whole soil systems may have accounted for most of the observed reduction. These results show that acceleration of in situ Cr(VI) reduction with addition of organic carbon is possible in even heavily contaminated soils and suggest that microbially dependent reduction pathways can be dominant.

This prospective study examined whether the psychological impact of organized mammography screening is influenced by women's pre-existing experience with breast cancer and perceived susceptibility (PS) to the disease. From a target population of 16,886, a random sample of women with a normal screening finding and all women with a false positive or a benign biopsy finding were included (N=1942). Data were collected with postal questionnaires 1-month before screening invitation and 2 and 12 months after screening. Response rate was 63% at baseline; 86, and 80% of the baseline participants responded to the follow-ups. Psychological impact was measured as anxiety (STAI-S), depression (BDI), health-related concerns (IAS), and breast cancer-specific beliefs and concerns. Data was analyzed with repeated measures analyses of variance, with estimates of effect size based on Eta-squared. Women with breast cancer experience had higher risk perception already before screening invitation; after screening they were also more distressed. Women with high PS were more distressed than women with low PS also at pre-invitation. The distress was not alleviated by screening, but instead remained even after normal mammograms. Experience and PS did not influence responses to different screening findings. Of the finding groups, false positives experienced most adverse effects: their risk perception increased and they reported most post-screening breast cancer-specific concerns. Furthermore, they became more frequent in breast self-examination (BSE) despite a simultaneous decrease in BSE self-efficacy. Our findings suggest that women with high PS and women with false positive screening finding may need individualized counseling and follow-up as much as women with a family history of breast cancer. Besides medical risk factors, women's own perceptions of susceptibility should be discussed during the screening process., (Copyright 2003 John Wiley & Sons, Ltd.)