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Chondritic meteorites (chondrites) contain evidence for the interaction of liquid water with the interiors of small bodies early in Solar System history. Here we review the processes, products and timings of the low-temperature aqueous alteration reactions in CR, CM, CI and ungrouped carbonaceous chondrites, the asteroids Ryugu and Bennu, and hydrated dark clasts in different types of meteorites. We first consider the nature of chondritic lithologies and the insights that they provide into alteration conditions, subdivided by the mineralogy and petrology of hydrated chondrites, the mineralogy of hydrated dark clasts, the effects of alteration on presolar grains, and the evolution of organic matter. We then describe the properties of the aqueous fluids and how they reacted with accreted material as revealed by physicochemical modelling and hydrothermal experiments, the analysis of fluid inclusions in aqueously formed minerals, and isotope tracers. Lastly, we outline the chronology of aqueous alteration reactions as determined using the 53Mn-53Cr and 129I-129Xe systems. [ABSTRACT FROM AUTHOR]

The effects of post-hydration heating over a broad range of temperatures are evident in many Mighei-like carbonaceous (CM) chondrites as a variety of mineral transitions. To better understand these processes and how a CM chondrite's starting composition may have affected them, we experimentally heated two meteorites with different degrees of aqueous alteration, Allan Hills 83100 and Murchison, at 25 °C temperature steps from 200 °C to 950 °C and 300 °C to 750 °C, respectively. During heating, synchrotron in situ X-ray diffraction patterns were collected. With the exception of calcite decomposition and its products, most mineral transitions were unaffected by starting composition. Key observations include: (1) partial decomposition of tochilinite at 200 °C, which indicates that tochilinite breakdown might be a two-stage process due to its intergrown layers of brucite/amakinite and mackinawite; (2) the breakdown of serpentine occurring at 300 °C with transitional phases appearing at 525 °C and 575–600 °C, while secondary olivine formed at 600 °C; (3) cronstedtite decomposing faster than lizardite, (4) the formation of secondary enstatite at 750 °C, and (5) calcite decomposition temperature differing significantly between meteorites, occurring at 725 °C and 575 °C in ALH 83100 and Murchison, respectively. The results for calcite are likely controlled by differences in its microstructure and chemical composition, related to the meteorite's impact history and degree of aqueous alteration. The difference in calcite decomposition temperature also explains the contrasts in the observed breakdown products, with clinopyroxene occurring in both meteorites, and oldhamite only in ALH 83100. Mineral transitions due to post-hydration heating have been characterized with a high resolution XRD method, enabling a better understanding of processes occurring on the parent asteroids of CM chondrites. [ABSTRACT FROM AUTHOR]

The temperature dependent order parameter provides important information on the nature of magnetism. Using traditional methods to study this parameter in two-dimensional (2D) magnets remains difficult, however, particularly for insulating antiferromagnetic (AF) compounds. Here, we show that its temperature dependence in AF MPS3 (M(II) = Fe, Co, Ni) can be probed via the anisotropy in the resonance frequency of rectangular membranes, mediated by a combination of anisotropic magnetostriction and spontaneous staggered magnetization. Density functional calculations followed by a derived orbital-resolved magnetic exchange analysis confirm and unravel the microscopic origin of this magnetization-induced anisotropic strain. We further show that the temperature and thickness dependent order parameter allows to deduce the material's critical exponents characterising magnetic order. Nanomechanical sensing of magnetic order thus provides a future platform to investigate 2D magnetism down to the single-layer limit. Van der Waals antiferromagnets offer a unique platform for studying magnetism in reduced dimensions, however, the low dimensionality, combined with lack of net magnetization, renders investigation challenging with conventional experimental probes. Here, Houmes et al show how van der Waals antiferromagnets can be investigated via the resonances of a vibrating rectangular membranes of this material. [ABSTRACT FROM AUTHOR]

Human milk contains over 200 distinct oligosaccharides, which are critical to shaping the developing neonatal gut microbiome. To investigate whether a complex mixture of human milk oligosaccharides (HMOs) would similarly modulate the adult gut microbiome, HMO-Concentrate derived from pooled donor breast milk was administered orally to 32 healthy adults for 7 days followed by 21 days of monitoring. Fecal samples were collected for 16S rRNA gene sequencing, shotgun metagenomics, and metabolomics analyses. HMO-Concentrate induced dose-dependent Bifidobacterium expansion, reduced microbial diversity, and altered microbial gene content. Following HMO cessation, a microbial succession occurred with diverse taxonomic changes—including Bacteroides expansion—that persisted through day 28. This was associated with altered microbial gene content, shifts in serum metabolite levels, and increased circulating TGFβ and IL-10. Incubation of cultured adult microbiota with HMO-Concentrate induced dose-dependent compositional shifts that were not recapitulated by individual HMOs or defined mixtures of the 10 most abundant HMOs in HMO-Concentrate at their measured concentrations. These findings support that pooled donor HMOs can exert direct effects on adult gut microbiota and that complex mixtures including low abundance HMOs present in donor milk may be required for maximum effect. Registration: ClinicalTrials.gov NCT05516225 [ABSTRACT FROM AUTHOR]

Background: Preventive screening at the point of care can increase desired clinical outcomes. However, the impact of repeated screening for tobacco use on receiving smoking cessation treatment among women Veteran population has not been documented. Objective: To examine screening for tobacco use using clinical reminders and the association between the number of screenings and prescription for cessation treatment. Design: A retrospective analysis using data from a 5-year implementation trial for cardiovascular risk identification conducted between December 2016 and March 2020. Subjects: Women patients who had at least one primary care visit with a women's health provider during the study period at five primary care clinics in the Veterans Affairs (VA) Healthcare System. Measures: The outcome is prescription of pharmacotherapy or referral to behavioral counseling for smoking cessation on or after the screening date. The exposure is the number of screenings for tobacco use from the trial and the annual VA national clinical reminders during the study period. Results: Of 6009 eligible patients, 5788 (96.3%) were screened at least once for tobacco use over five calendar years, and 2784 of those screened (48.1%) were reported as current and former smokers. Among current and former smokers, 709 (25.5%) received a prescription and/or referral for smoking cessation. In the adjusted model, the average predicted probability of prescription and/or referral for smoking cessation was 13.7% among current and former smokers screened once over 5 years, 18.6% among screened twice, 26.5% among screened thrice, 32.9% among screened four times, and 41.7% among screened five or six times. Conclusions: Repeated screening was associated with higher predicted probabilities of being prescribed smoking cessation treatment. [ABSTRACT FROM AUTHOR]

Introduction: Different strategies were proposed to stratify cardiovascular risk and assess the appropriate use of statins in patients with chronic kidney disease (CKD). Aim: (1) To apply two strategies on the management of lipids in patients with CKD, analyzing what proportion of patients received lipid-lowering treatment and how many patients without statin therapy would be candidates for receiving them; (2) to identify how many patients achieve the lipid goals. Methods: A cross-sectional study was performed. Patients aged between 18 to 70 years and CKD with an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 (without hemodialysis) were included. The indications for statin therapy according to 2019 ESC/EAS and 2013 KDIGO guidelines were analyzed as well as the achievement of LDL-C goals. Results: A total of 300 patients were included. According to ESC/EAS guidelines, 62.3 and 37.7% of the population was classified at high or very high cardiovascular risk. In total, 52% of patients received statins. Applying the 2013 KDIGO and the 2019 ESC/EAS guidelines, 92.4 and 95.8% of the population without lipid-lowering treatment were eligible for statin therapy, respectively. Globally, only 9.1 and 10.6% of the patients with high or very high risk achieved the suggested lipid goals. Conclusion: A large proportion of patients with CKD showed considerable cardiovascular risk and were eligible for statin therapy according to the two strategies evaluated. However, observed statin use was deficient and current lipid goals were not achieved in most cases. [ABSTRACT FROM AUTHOR]

Two-dimensional magnetic materials with strong magnetostriction are attractive systems for realizing strain-tuning of the magnetization in spintronic and nanomagnetic devices. This requires an understanding of the magneto-mechanical coupling in these materials. In this work, we suspend thin Cr2Ge2Te6 layers and their heterostructures, creating ferromagnetic nanomechanical membrane resonators. We probe their mechanical and magnetic properties as a function of temperature and strain by observing magneto-elastic signatures in the temperature-dependent resonance frequency near the Curie temperature, TC. We compensate for the negative thermal expansion coefficient of Cr2Ge2Te6 by fabricating heterostructures with thin layers of WSe2 and antiferromagnetic FePS3, which have positive thermal expansion coefficients. Thus we demonstrate the possibility of probing multiple magnetic phase transitions in a single heterostructure. Finally, we demonstrate a strain-induced enhancement of TC in a suspended Cr2Ge2Te6-based heterostructure by 2.5 ± 0.6 K by applying a strain of 0.026% via electrostatic force. [ABSTRACT FROM AUTHOR]

Telemedicine (TM) is a useful tool to extend medical care during a pandemic. TM was extensively utilized in Singapore during the COVID-19 pandemic as part of the Nation's COVID-19 healthcare strategy. Patients were risk stratified to prioritize limited healthcare resources and the Telemedicine Allocation Reconciliation System (TMARS) was adapted to monitor and manage limited TM resources. High-Risk patients (Protocol 1) had an escalation rate of 4.87%, compared to the non-High-Risk patients' 0.002% and TM doctors spent an average of six hours to complete one tele-consultation. In order to optimize the efficiency of the TM system, an enhanced monitoring system was implemented in March 2022. The intent was to focus monitoring efforts on the High-Risk patients. High-Risk patients reporting sick for the first time were prioritized to receive tele-consultations through this system. With the aid of a data-driven dashboard, the Operations Control and Monitoring team (OCM) was able to closely monitor the performance of the various TM providers (TMPs), sent them timely reminders and re-assigned patients to other TMPs when the requisite turnaround time was not met. Implementing the enhanced monitoring system resulted in a significant reduction in the average time taken to provide tele-consultations. After 3 months of implementation, the percentages of consultations completed within two hours were raised from 75.7% (February 2022) to 96.8% (May 2022), greatly increasing productivity and efficiency. [ABSTRACT FROM AUTHOR]

Black men who have sex with men and women (BMSMW) experience pressure to fill hypermasculine ideals and may not identify with "gay" cultural norms. Existing measures of gender role expectations and internalized homophobia are not culturally appropriate for BMSMW. Researchers generally measure categorical identification with race, gender, and sexual orientation groups separately, whereas BMSMW may identify with multiple categories. We modified the Gender Role Conflict Scale to create the M-GRCS and the Internalized Homophobia Scale to include biphobia (Internalized Bi/Homophobia Scale, IBHS). To examine identification at the intersection of race, gender, and sexual orientation, we created 11 Integrated Race and Sexuality Scale (IRSS) items. With data from 429 BMSMW, we conducted exploratory factor analysis of the 59 items using categorical principal axis factoring with unweighted least squares extraction and Promax factor rotation. We created simple-summated multi-item scales and evaluated their construct validity. The rotated solution yielded four factors with 47 items and a simple factor structure: M-GRCS defined two factors (α =.93 for restricted emotionality/affection;.87 for success/power/competition); the IBHS (α =.89) and IRSS (α =.74) each defined a single factor. The IRSS factor was positively correlated with the Lukwago Racial Pride Scale, r(417) =.40. The IBHS factor was negatively correlated with the IRSS factor, r(414) = −.22. The two M-GRCS factors suggest that the construct of hypermasculinity impacts BMSMW. The high IBHS reliability indicates that homophobia and biphobia were positively correlated in this sample. These three scales have potential for future studies with BMSMW. [ABSTRACT FROM AUTHOR]

Background: Given persistent gaps in coordination of care for medically complex primary care patients, efficient strategies are needed to promote better care coordination. Objective: The Coordination Toolkit and Coaching project compared two toolkit-based strategies of differing intensity to improve care coordination at VA primary care clinics. Design: Multi-site, cluster-randomized QI initiative. Participants: Twelve VA primary care clinics matched in 6 pairs. Interventions: We used a computer-generated allocation sequence to randomize clinics within each pair to two implementation strategies. Active control clinics received an online toolkit with evidence-based tools and QI coaching manual. Intervention clinics received the online toolkit plus weekly assistance from a distance coach for 12 months. Main Measures: We quantified patient experience of general care coordination using the Health Care System Hassles Scale (primary outcome) mailed at baseline and 12-month follow-up to serial cross-sectional patient samples. We measured the difference-in-difference (DiD) in clinic-level-predicted mean counts of hassles between coached and non-coached clinics, adjusting for clustering and patient characteristics using zero-inflated negative binomial regression and bootstrapping to obtain 95% confidence intervals. Other measures included care coordination QI projects attempted, tools adopted, and patient-reported exposure to projects. Key Results: N = 2,484 (49%) patients completed baseline surveys and 2,481 (48%) completed follow-ups. Six coached clinics versus five non-coached clinics attempted QI projects. All coached clinics versus two non-coached clinics attempted more than one project or projects that were multifaceted (i.e., involving multiple components addressing a common goal). Five coached versus three non-coached clinics used 1–2 toolkit tools. Both the coached and non-coached clinics experienced pre-post reductions in hassle counts over the study period (− 0.42 (− 0.76, − 0.08) non-coached; − 0.40 (− 0.75, − 0.06) coached). However, the DiD (0.02 (− 0.47, 0.50)) was not statistically significant; coaching did not improve patient experience of care coordination relative to the toolkit alone. Conclusion: Although coached clinics attempted more or more complex QI projects and used more tools than non-coached clinics, coaching provided no additional benefit versus the online toolkit alone in patient-reported outcomes. Trial Registration: ClinicalTrials.gov identifier: NCT03063294 [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate-co-acrylic acid) [P(MMA-co-AA)] incorporated with 0–9 wt% of trimethoxyvinylsilane (TMVS) has been studied to investigate the effect of TMVS on the adhesion properties of P(MMA-co-AA) nanospheres coated on silicon substrate as well as on the power conversion efficiency (PCE) of silicon solar module coated with the polymer nanospheres. The incorporation of 7 and 9 wt% of TMVS into the copolymer has been found to render the copolymer stronger adhesion to glass substrate than the samples with lower amount of TMVS in them. The coating of the P(MMA-co-AA) nanospheres on the glass surface of solar module increases the light harvesting efficiency by serving as an anti-reflective layer. Solar module coated with an array of P(MMA-co-AA) nanospheres with 7 wt% of TMVS yielded the highest PCE enhancement of 98% under the illumination of an AM1.5 solar simulator. The natural weathering results indicate that the copolymer with 7% of TMVS was able to withstand prolonged natural weathering exposure and remained reasonably effective in PCE enhancement up to 130 days of outdoor exposure. This study demonstrates a cost-effective technique to bind [P(MMA-co-AA)] nanospheres onto the silicon surface of solar module via siloxane linkages and thus increases the PCE of the solar module effectively. The Tg of the copolymer increased linearly from 110.31 to 118.42 °C when 0–9 wt% of TMVS was added into it. Thermogravimetry results indicate that the incorporation of TMVS does not give any significant effect on the Td of the copolymer, which occurs at about 390 °C. [ABSTRACT FROM AUTHOR]

Mechanical sources of nonlinear damping play a central role in modern physics, from solid-state physics to thermodynamics. The microscopic theory of mechanical dissipation suggests that nonlinear damping of a resonant mode can be strongly enhanced when it is coupled to a vibration mode that is close to twice its resonance frequency. To date, no experimental evidence of this enhancement has been realized. In this letter, we experimentally show that nanoresonators driven into parametric-direct internal resonance provide supporting evidence for the microscopic theory of nonlinear dissipation. By regulating the drive level, we tune the parametric resonance of a graphene nanodrum over a range of 40–70 MHz to reach successive two-to-one internal resonances, leading to a nearly two-fold increase of the nonlinear damping. Our study opens up a route towards utilizing modal interactions and parametric resonance to realize resonators with engineered nonlinear dissipation over wide frequency range. Nonlinear dissipation is frequently observed in nanomechanical resonators, but its microscopic origin remains unclear. Here, nonlinear damping is found to be enhanced in graphene nanodrums close to internal resonance conditions, providing insights on the mechanisms at the basis of this phenomenon. [ABSTRACT FROM AUTHOR]

The high flexibility, impermeability and strength of graphene membranes are key properties that can enable the next generation of nanomechanical sensors. However, for capacitive pressure sensors, the sensitivity offered by a single suspended graphene membrane is too small to compete with commercial sensors. Here, we realize highly sensitive capacitive pressure sensors consisting of arrays of nearly ten thousand small, freestanding double-layer graphene membranes. We fabricate large arrays of small-diameter membranes using a procedure that maintains the superior material and mechanical properties of graphene, even after high-temperature annealing. These sensors are readout using a low-cost battery-powered circuit board, with a responsivity of up to 47.8 aF Pa−1 mm−2, thereby outperforming the commercial sensors. Sensors that perform well under pressure: Arrays of tiny graphene membranes exhibit excellent performance as pressure sensors, offering a competitive, low-cost alternative to commercially available systems. Graphene offers a durable and resilient material for sensors that generate a capacitive readout to pressure changes, but individual membranes are not sufficiently sensitive. Researchers led by Makars Šiškins and Peter Steeneken of the Delft University of Technology in the Netherlands have devised a strategy for fabricating graphene sensor arrays that overcome this limitation. Their method yields millimeter-scale assemblies of 10,000 double-layered graphene membranes, which can in turn be connected to an inexpensive battery-powered circuit board. The authors demonstrate that this system can outperform a state-of-the-art commercial pressure sensor, and propose that further improvements to the design and fabrication of these arrays could improve their responsiveness by a full order of magnitude. [ABSTRACT FROM AUTHOR]

Background/Aims: We examined the quality of palliative care received by patients with decompensated cirrhosis using an explicit set of palliative care quality indicators (QIs) for patients with end-stage liver disease (PC-ESLD). Methods: We identified patients newly diagnosed with decompensated cirrhosis at a single veterans health center and followed up them for 2 years or until death. We piloted measurement of PC-ESLD QIs in all patients confirmed to have ESLD using a chart abstraction tool. Results: Out of 167 patients identified using at least one sampling strategy, 62 were confirmed to meet ESLD criteria with chart abstraction. Ninety-eight percent of veterans in the cohort were male, mean age at diagnosis was 61 years, and 74% were White. The overall QI pass rate was 68% (64% for information care planning QIs and 76% for supportive care QIs). Patients receiving specialty palliative care consultation were more likely to receive information care planning QIs (67% vs. 37%, p = 0.02). The best performing sampling strategy had a sensitivity of 62% and specificity of 60%. Conclusion: Measuring the quality of palliative care for patients with ESLD is feasible in the veteran population. Our single-center data suggest that the quality of palliative care is inadequate in the veteran population with ESLD, though patients offered specialty palliative care consultation and those affected by homelessness, drug, and alcohol abuse may receive better care. Our combination of ICD-9 codes can be used to identify a cohort of patients with ESLD, though better sensitivity and specificity may be needed. [ABSTRACT FROM AUTHOR]

The reduced dimensionality of two-dimensional (2D) materials results in characteristic types of magnetically and electronically ordered phases. However, only few methods are available to study this order, in particular in ultrathin insulating antiferromagnets that couple weakly to magnetic and electronic probes. Here, we demonstrate that phase transitions in thin membranes of 2D antiferromagnetic FePS3, MnPS3 and NiPS3 can be probed mechanically via the temperature-dependent resonance frequency and quality factor. The observed relation between mechanical motion and antiferromagnetic order is shown to be mediated by the specific heat and reveals a strong dependence of the Néel temperature of FePS3 on electrostatically induced strain. The methodology is not restricted to magnetic order, as we demonstrate by probing an electronic charge-density-wave phase in 2H-TaS2. It thus offers the potential to characterize phase transitions in a wide variety of materials, including those that are antiferromagnetic, insulating or so thin that conventional bulk characterization methods become unsuitable. Electronics and magnetic phase transitions typically do not involve mechanical degrees of freedom directly, but their impact on thermodynamic properties affects the mechanical response of a material. Here the authors show that resonators made from 2D materials exhibit anomalies at phase transitions. [ABSTRACT FROM AUTHOR]

From all primary care patients at these sites, a trained chart abstractor identified women who received a PCP request for specialty consultation for UI care and/or UI medication prescription (oxybutynin or tolterodine, since other UI medications were restricted to specialists). Trial Registration ClinicalTrials.gov NCT01918072; VA Greater Los Angeles Healthcare System IRB approved protocol number PCC#2012-111579. Our resultant sample included 130 new UI patients (40% of all UI patients) (Table 1). [Extracted from the article]

Background: The Veterans Health Administration (VA) has invested substantially in evidence-based mental health care. Yet no electronic performance measures for assessing the level at which the population of Veterans with depression receive appropriate care have proven robust enough to support rigorous evaluation of the VA's depression initiatives.Objective: Our objectives were to develop prototype longitudinal electronic population-based measures of depression care quality, validate the measures using expert panel judgment by VA and non-VA experts, and examine detection, follow-up and treatment rates over a decade (2000-2010). We describe our development methodology and the challenges to creating measures that capture the longitudinal course of clinical care from detection to treatment.Design and Participants: Data come from the National Patient Care Database and Pharmacy Benefits Management Database for primary care patients from 1999 to 2011, from nine Veteran Integrated Service Networks.Measures: We developed four population-based quality metrics for depression care that incorporate a 6-month look back and 1-year follow-up: detection of a new episode of depression, 84 and 180 day follow-up, and minimum appropriate treatment 1-year post detection. Expert panel techniques were used to evaluate the measure development methodology and results. Key challenges to creating valid longitudinal measures are discussed.Key Results: Over the decade, the rates for detection of new episodes of depression remained stable at 7-8 %. Follow-up at 84 and 180 days were 37 % and 45 % in 2000 and increased to 56 % and 63 % by 2010. Minimum appropriate treatment remained relatively stable over the decade (82-84 %).Conclusions: The development of valid longitudinal, population-based quality measures for depression care is a complex process with numerous challenges. If the full spectrum of care from detection to follow-up and treatment is not captured, performance measures could actually mask the clinical areas in need of quality improvement efforts. [ABSTRACT FROM AUTHOR]

Background: Lower extremity arterial disease (LEAD) occurs more common in patients with diabetes than without diabetes. Microvascular complications of diabetes contribute to higher rates of adverse limb events in patients with LEAD. Blood flow in the macrocirculation and microcirculation is reduced with increasing low-shear and high-shear blood viscosity. We hypothesize that the adenosine enhancing properties of ticagrelor will reduce low-shear blood viscosity and improve microcirculatory flow in the dorsum of the feet of patients with type 2 diabetes. Ticagrelor is a P2Y12 receptor antagonist with evidence of cardiovascular event reduction in patients with acute coronary syndromes and those with a previous myocardial infarction. In a large multicenter trial of patients with symptomatic LEAD and a history of limb revascularization, ticagrelor was no more effective than clopidogrel in reducing cardiovascular disease events; however, this trial was not designed to investigate microvascular complications of diabetes.Design: Hema-kinesis will evaluate whether ticagrelor monotherapy or ticagrelor combined with aspirin as compared with aspirin monotherapy can reduce blood viscosity-dependent blood flow in the feet of type 2 diabetes patients with LEAD. Eligible study participants will be randomized into a three-arm double-dummy crossover trial design. All subjects will have baseline blood viscosity measurements and determinations of microvascular flow using laser Doppler flowmetry.Summary: If the results of Hema-kinesis are positive, ticagrelor should be considered as treatment to reduce microvascular complications of LEAD in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The advent of immune checkpoint targeted immunotherapy has seen a spectrum of immune-related phenomena in both tumor responses and toxicities. We describe a case of pseudoprogression that pushes the limits of immune-related response criteria and challenges the boundaries and definitions set by trial protocols. A middle-aged man with conventional clear cell renal cell carcinoma (RCC) had received multiple prior systemic treatments including vascular endothelial growth factor receptor tyrosine kinase inhibitors, as well as multiple surgeries and radiotherapy treatments. He was eventually started on nivolumab—the anti-programmed death receptor-1 monoclonal antibody approved for the treatment of advanced RCC. Clinical deterioration was observed soon after a 100 mg dose of nivolumab, with onset of acute renal failure and declining performance status. Radiologic progression was documented in multiple sites including worsening tumor infiltration of his residual kidney. The patient was on palliative treatment and visited by the home hospice team in an end-of-life situation. The patient unexpectedly improved and went on to achieve a durable tumor response. The case is illustrative of an extreme manifestation of pseudoprogression, and impels us to probe the assumptions and controversies surrounding this phenomenon. [ABSTRACT FROM AUTHOR]

Mars hosts the solar system's largest volcanoes. Although their size and impact crater density indicate continued activity over billions of years, their formation rates are poorly understood. Here we quantify the growth rate of a Martian volcano by 40Ar/39Ar and cosmogenic exposure dating of six nakhlites, meteorites that were ejected from Mars by a single impact event at 10.7 ± 0.8 Ma (2σ). We find that the nakhlites sample a layered volcanic sequence with at least four discrete eruptive events spanning 93 ± 12 Ma (1416 ± 7Ma to 1322 ± 10 Ma (2σ)). A non-radiogenic trapped 40Ar/36Ar value of 1511 ± 74 (2σ) provides a precise and robust constraint for the mid-Amazonian Martian atmosphere. Our data show that the nakhlite-source volcano grew at a rate of ca. 0.4-0.7mMa-1-three orders of magnitude slower than comparable volcanoes on Earth, and necessitating that Mars was far more volcanically active earlier in its history. [ABSTRACT FROM AUTHOR]

Owing to its diagenetic instability, aragonite is rare in the geological record and almost entirely absent from pre-carboniferous sedimentary rocks. The former presence of this mineral in older deposits has to be inferred from petrographic, chemical or isotopic proxies. Crystals of aragonite that formed around 4563 million years ago occur in carbonaceous chondrite meteorites, showing that under certain conditions, the orthorhombic polymorph of Ca-carbonate can survive essentially indefinitely. Together with other carbonate minerals, phyllosilicates and sulphides, this aragonite formed by low-temperature water-mediated alteration of anhydrous minerals and glass in the interior of the meteorite's parent asteroid(s). The survival of aragonite for such a long time can be attributed to the loss of free water by its incorporation into phyllosilicates, and to the very low permeability of the fine-grained and organic-rich rock matrix that prevented the ingress of fresh solutions via intergranular flow. By analogy with these meteorites, terrestrial aragonite is likely to survive where it has been similarly isolated from liquid water, particularly in organic-rich mudrocks, and such deposits may provide important new evidence for deducing the original mineralogy of skeletal and non-skeletal carbonates in deep-time. [ABSTRACT FROM AUTHOR]

Background: Patients with gastroesophageal reflux disease (GERD) often seek alternative therapy for inadequate symptom control, with over 40 % not responding to medical treatment. We evaluated the long-term safety, efficacy, and durability of response to radiofrequency treatment of the lower esophageal sphincter (Stretta). Methods: Using an intent-to-treat analysis, we prospectively assessed 217 patients with medically refractory GERD before and after Stretta. There was no concurrent control group in the study. Primary outcome measure was normalization of GERD-health-related quality of life (GERD-HRQL) in 70 % or greater of patients at 10 years. Secondary outcomes were 50 % reduction or elimination of proton pump inhibitors (PPIs) and 60 % or greater improvement in satisfaction at 10 years. Successful treatment was defined as achievement of secondary outcomes in a minimum of 50 % of patients. Complications and effect on existing comorbidities were evaluated. The results of a 10-year study are reported. Results: The primary outcome was achieved in 72 % of patients (95 % confidence interval 65-79). For secondary outcomes, a 50 % or greater reduction in PPI use occurred in 64 % of patients, (41 % eliminating PPIs entirely), and a 60 % or greater increase in satisfaction occurred in 54 % of patients. Both secondary endpoints were achieved. The most common side effect was short-term chest pain (50 %). Pre-existing Barrett's metaplasia regressed in 85 % of biopsied patients. No cases of esophageal cancer occurred. Conclusions: In this single-group evaluation of 217 patients before and after Stretta, GERD-HRQL scores, satisfaction, and PPI use significantly improved and results were immediate and durable at 10 years. [ABSTRACT FROM AUTHOR]

Fuelled by the obesity epidemic, there is considerable interest in the developmental origins of white adipose tissue (WAT) and the stem and progenitor cells from which it arises. Whereas increased visceral fat mass is associated with metabolic dysfunction, increased subcutaneous WAT is protective. There are six visceral fat depots: perirenal, gonadal, epicardial, retroperitoneal, omental and mesenteric, and it is a subject of much debate whether these have a common developmental origin and whether this differs from that for subcutaneous WAT. Here we show that all six visceral WAT depots receive a significant contribution from cells expressing Wt1 late in gestation. Conversely, no subcutaneous WAT or brown adipose tissue arises from Wt1-expressing cells. Postnatally, a subset of visceral WAT continues to arise from Wt1-expressing cells, consistent with the finding that Wt1 marks a proportion of cell populations enriched in WAT progenitors. We show that all visceral fat depots have a mesothelial layer like the visceral organs with which they are associated, and provide several lines of evidence that Wt1-expressing mesothelium can produce adipocytes. These results reveal a major ontogenetic difference between visceral and subcutaneous WAT, and pinpoint the lateral plate mesoderm as a major source of visceral WAT. They also support the notion that visceral WAT progenitors are heterogeneous, and suggest that mesothelium is a source of adipocytes. [ABSTRACT FROM AUTHOR]

Cathodoluminescence (CL) spectra of unirradiated, He ion-implanted and electron-irradiated plagioclase minerals contain the following emission bands: (1) below 300 nm due to Pb, (2) at ~320 and ~350 nm to Ce, (3) at 380-420 nm to Eu, Ti and/or Al-O-Al/Ti defects, (4) at 560-580 nm to Mn and (5) at 720-760 nm to Fe. During the implantation of He ion, much of their energy may be dissipated by partial destruction and strain of the feldspar framework, resulting in quenching of CL. Deconvolution of CL spectra acquired from albite and oligoclase reveals an emission component at 1.86 eV (666 nm) assigned to a radiation-induced defect center associated with Na atoms. As its intensity increases with radiation dose, this emission component has potential for geodosimetry and geochronometry. Electron irradiation causes Na migration in plagioclase, and then a considerable reduction in intensity of emissions assigned to impurity centers, which is responsible for an alteration in the energy state or a decrease in luminescence efficiency following the change of activation energy. Emission intensity at 1.86 eV positively correlates with electron irradiation time for unimplanted and He ion-implanted albite and oligoclase, but negatively for the implanted albite above 1.07 × 10 C/cm. It implies that radiation halo produced by α-particles should not be measured using CL spectroscopy to estimate β radiation dose on albite in the high radiation level. [ABSTRACT FROM AUTHOR]

Eight feldspar phases have been distinguished within individual alkali feldspar primocrysts in laminated syenite members of the layered syenite series of the Klokken intrusion. The processes leading to the formation of the first four phases have been described previously. The feldspars crystallized as homogeneous sodian sanidine and exsolved by spinodal decomposition, between 750 and 600 °C, depending on bulk composition, to give fully coherent, strain-controlled braid cryptoperthites with sub-μm periodicities. Below ~500 °C, in the microcline field, these underwent a process of partial mutual replacement in a deuteric fluid, producing coarse (up to mm scale), turbid, incoherent patch perthites. We here describe exsolution and replacement processes that occurred after patch perthite formation. Both Or- and Ab-rich patches underwent a new phase of coherent exsolution by volume diffusion. Or-rich patches began to exsolve albite lamellae by coherent nucleation in the range 460-340 °C, depending on patch composition, leading to film perthite with ≤1 μm periodicities. Below ~300 °C, misfit dislocation loops formed, which were subsequently enlarged to nanotunnels. Ab-rich patches (bulk composition ~AbOrAn), in one sample, exsolved giving peristerite, with one strong modulation with a periodicity of ~17 nm and a pervasive tweed microtexture. The Ab-rich patches formed with metastable disorder below the peristerite solvus and intersected the peristerite conditional spinodal at ~450 °C. This is the first time peristerite has been imaged using TEM within any perthite, and the first time peristerite has been found in a relatively rapidly cooled geological environment. The lamellar periodicities of film perthite and peristerite are consistent with experimentally determined diffusion coefficients and a calculated cooling history of the intrusion. All the preceding textures were in places affected by a phase of replacement correlating with regions of extreme optical turbidity. We term this material ultra porous late feldspar (UPLF). It is composed predominantly of regions of microporous very Or-rich feldspar (mean AbOrAn) associated with very pure porous albite (AbOrAn) implying replacement below 170-90 °C, depending on degree of order. In TEM, UPLF has complex, irregular diffraction contrast similar to that previously associated with low-temperature albitization and diagenetic overgrowths. Replacement by UPLF seems to have been piecemeal in character. Ghost-like textural pseudomorphs of both braid and film parents occur. Formation of patch perthite, film perthite and peristerite occurred 10-10 year after emplacement, but there are no microtextural constraints on the age of UPLF formation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Depression management can be challenging for primary care (PC) settings. While several evidence-based models exist for depression care, little is known about the relationships between PC practice characteristics, model characteristics, and the practice's choices regarding model adoption. OBJECTIVE: We examined three Veterans Affairs (VA)-endorsed depression care models and tested the relationships between theoretically-anchored measures of organizational readiness and implementation of the models in VA PC clinics. DESIGN: 1) Qualitative assessment of the three VA-endorsed depression care models, 2) Cross-sectional survey of leaders from 225 VA medium-to-large PC practices, both in 2007. MAIN MEASURES: We assessed PC readiness factors related to resource adequacy, motivation for change, staff attributes, and organizational climate. As outcomes, we measured implementation of one of the VA-endorsed models: collocation, Translating Initiatives in Depression into Effective Solutions (TIDES), and Behavioral Health Lab (BHL). We performed bivariate and, when possible, multivariate analyses of readiness factors for each model. KEY RESULTS: Collocation is a relatively simple arrangement with a mental health specialist physically located in PC. TIDES and BHL are more complex; they use standardized assessments and care management based on evidence-based collaborative care principles, but with different organizational requirements. By 2007, 107 (47.5 %) clinics had implemented collocation, 39 (17.3 %) TIDES, and 17 (7.6 %) BHL. Having established quality improvement processes (OR 2.30, [1.36, 3.87], p = 0.002) or a depression clinician champion (OR 2.36, [1.14, 4.88], p = 0.02) was associated with collocation. Being located in a VA regional network that endorsed TIDES (OR 8.42, [3.69, 19.26], p < 0.001) was associated with TIDES implementation. The presence of psychologists or psychiatrists on PC staff, greater financial sufficiency, or greater spatial sufficiency was associated with BHL implementation. CONCLUSIONS: Both readiness factors and characteristics of depression care models influence model adoption. Greater model simplicity may make collocation attractive within local quality improvement efforts. Dissemination through regional networks may be effective for more complex models such as TIDES. [ABSTRACT FROM AUTHOR]

Energetic particles constitute an important component of the heliospheric plasma environment. They range from solar energetic particles in the inner heliosphere to the anomalous cosmic rays accelerated at the interface of the heliosphere with the local interstellar medium. Although stochastic acceleration by fluctuating electric fields and processes associated with magnetic reconnection may account for some of the particle populations, the majority are accelerated by the variety of shock waves present in the solar wind. This review focuses on 'gradual' solar energetic particle (SEP) events including their energetic storm particle (ESP) phase, which is observed if and when an associated shock wave passes Earth. Gradual SEP events are the intense long-duration events responsible for most space weather disturbances of Earth's magnetosphere and upper atmosphere. The major characteristics of gradual SEP events are first described including their association with shocks and coronal mass ejections (CMEs), their ion composition, and their energy spectra. In the context of acceleration mechanisms in general, the acceleration mechanism responsible for SEP events, diffusive shock acceleration, is then described in some detail including its predictions for a planar stationary shock, shock modification by the energetic particles, and wave excitation by the accelerating ions. Finally, some complexities of shock acceleration are addressed, which affect the predictive ability of the theory. These include the role of temporal and spatial variations, the distinction between the plasma and wave compression ratios at the shock, the injection of thermal plasma at the shock into the process of shock acceleration, and the nonlinear evolution of ion-excited waves in the vicinity of the shock. [ABSTRACT FROM AUTHOR]

Charge contrast imaging in the scanning electron microscope can provide new insights into the scale and composition of alkali feldspar microtextures, and such information helps considerably with the interpretation of their geological histories and results of argon isotope thermochronological analyses. The effectiveness of this technique has been illustrated using potassium-rich alkali feldspars from the Dartmoor granite (UK). These feldspars contain strain-controlled lamellar crypto- and microperthites that are cross-cut by strain-free deuteric microperthites. The constituent albite- and orthoclase-rich phases of both microperthite generations can be readily distinguished by atomic number contrast imaging. The charge contrast results additionally show that sub-micrometre-sized albite 'platelets' are commonplace between coarser exsolution lamellae and occur together to make cryptoperthites. Furthermore, charge contrast imaging reveals that the orthoclase-rich feldspar is an intergrowth of two phases, one that is featureless with uniform contrast and another that occurs as cross-cutting veins and grains with the {110} adularia habit. Transmission electron microscopy shows that the featureless feldspar is tweed orthoclase, whereas the veins and euhedral grains are composed of irregular microcline that has formed from orthoclase by 'unzipping' during deuteric or hydrothermal alteration. The charge contrast imaging results are especially important in demonstrating that deuteric perthites are far more abundant in alkali feldspars than would be concluded from investigations using conventional microscopy techniques. The unexpected presence of such a high volume of replacement products has significant implications for understanding the origins and geological histories of crustal rocks and the use of alkali feldspars in geo- and thermochronology. Whilst the precise properties of feldspars that generate contrast remain unclear, the similarity between charge contrast images and corresponding cathodoluminescence images of deuteric microperthites indicates that trace element chemistry and possibly also elastic strain within the crystal play a major role. [ABSTRACT FROM AUTHOR]

Limited research has examined the role that social support, stress, stigma and HIV disclosure play in retention in HIV care for African Americans and Latinos. Among 398 Latino and African American men who have sex with men (MSM) and women, the major predictor of retention in HIV care was disclosure of HIV status to more social network members (OR = 1.5; 95% CI: 1.1, 1.9). Among those who had disclosed ( n = 334), female gender (OR = 1.8, 95% CI: 1.1, 3.1) and disclosure of HIV status to more network members (OR = 1.5, 95% CI: 1.1, 1.9) was associated with retention in HIV care. General stress was associated with retention in care (OR = 1.2; 95% CI: 1.1, 1.3) for African American MSM who had disclosed. More MSM-stigma was associated with poorer retention (OR = 0.9; 95% CI: 0.8, 0.9) for Latino MSM. Interventions that help patients safely disclose their HIV status to more social network members may improve HIV care retention as would social network counseling for Latino MSM to reduce MSM-stigma. [ABSTRACT FROM AUTHOR]

ute pseudogout of the neck, also known as the crowned dens syndrome, is a rare cause of neck pain characterised by crystalline deposition in periodontoid articular tissues. It is typified clinically by severe cervical pain and stiffness, often in conjunction with pyrexia and raised inflammatory markers. As such, it is often misdiagnosed. We report 2 cases of crowned dens syndrome masquerading respectively as meningitis and polymyalgia rheumatica, and review the literature with particular attention to the clinical and radiological aspects of this under-recognised condition. [ABSTRACT FROM AUTHOR]

Outgrowths of zircon and xenotime are abundant on detrital zircon in a greenschist facies regional metamorphic slate from the Scottish Highlands. Back-scattered electron images reveal that ca. 3-μm wide zircon outgrowths are porous, inclusion-rich and contain fine-grained intergrowths with xenotime. Focused ion beam milling, transmission electron microscopy and low-voltage scanning transmission electron microscopy show that the outgrowth microstructure is complex, composed of mis-orientated nano-crystalline zircon and a poorly crystalline zircon–xenotime complex. Well-defined micron-sized xenotime is also present within the outgrowth. Micro-textures show that the outgrowth developed in a polyphase history during cooling and exhumation. Accommodation space for the outgrowth is probably generated by a combination of thermal decompaction and the migration of defects in adjacent quartz driven by the force of crystallisation. Zircon may be unique in its ability to record textural evidence of events during uplift and exhumation that are not recorded in major silicate phases. [ABSTRACT FROM AUTHOR]

Intracrystal microtextures formed by a process of mutual replacement in alkali feldspars record fluid–rock reactions that have affected large volumes of the Earth’s crust. Regular, ≤1 μm-scale ‘strain-controlled’ perthitic microtextures coarsen, by up to 103, by a dissolution–reprecipitation process, producing microporous patch or vein perthites on scales >100 μm. We have developed earlier studies of such reactions in alkali feldspar cm-scale primocrysts in layered syenites from the Klokken intrusion, South Greenland. We present new hyperspectral CL, SEM images, and laser ICPMS analytical data, and discuss the mechanism of such replacement reactions. The feldspars grew as homogeneous sodic sanidines which unmixed and ordered by volume diffusion during cooling into the microcline field at ~450°C, giving regular, fully coherent ‘braid’ cryptoperthite. At ≤450°C the crystals reacted with a circulating post-magmatic aqueous fluid. The braid perthite behaved as a single reactant ‘phase’ which was replaced by two product phases, incoherent subgrains of low albite and microcline, with micropores at their boundaries. The driving force for the reactions was coherency strain energy, which was greater than the surface energy in the subgrain mosaic. The external euhedral crystal shapes and bulk major element composition of the primocrysts were unchanged but they became largely pseudomorphs composed of subgrains usually with the ‘pericline’ and ‘adularia’ habits (dominant {110} and subordinate {010} morphology) characteristic of low T growth. The subgrains have an epitactic relationship with parent braid perthite. Individual subgrains show oscillatory zoning in CL intensity, mainly at blue wavelengths, which correlates with tetrahedral Ti. Regular zoning is sometimes truncated by irregular, discordant surfaces suggesting dissolution, followed by resumption of growth giving regular zoning. Zones can be traced through touching subgrains, of both albite and microcline, for distances up to ~500 μm. At ≤340°C, the microcline subgrains underwent a third stage of unmixing to give straight lamellar film perthites with periodicities of ~1 μm, which with further cooling became semicoherent by the development of spaced misfit dislocations. Sub-grain growth occurred in fluid films that advanced through the elastically strained braid perthite crystals, which dissolved irreversibly. Braid perthite was more soluble than the strain-free subgrain mosaics which precipitated from the supersaturated solution. Some volumes of braid texture have sharp surfaces that suggest rapid dissolution along planes with low surface energies. Others have complex, diffuse boundaries that indicate a phase of coherent lamellar straightening by volume diffusion in response to strain relief close to a slowly advancing interface. Nucleation of strain-free subgrains was the overall rate-limiting step. To minimise surface energy subgrains grew with low energy morphologies and coarsened by grain growth, in fluid films whose trace element load (reflected in the oscillatory zoning) was dictated by the competitive advance of subgrains over a range of a few tens of mm. The cross-cutting dissolution surfaces suggest influxes of fresh fluid. Removal of feldspar to give 2 vol% porosity would require a feldspar:fluid ratio of ~1:26 (by wt). The late reversion to strain-controlled exsolution in microcline subgrains is consistent with loss of fluid above 340°C following depressurization of the intrusion. A second paper (Part II) describes trace element partitioning between the albite and microcline subgrains, and discusses the potential of trace elements as a low- T geothermometer. [ABSTRACT FROM AUTHOR]

Perthitic alkali feldspar primocrysts in layered syenites in the Klokken intrusion in South Greenland, underwent dissolution–reprecipitation reactions in a circulating post-magmatic aqueous fluid at ~450°C, and are to a large degree pseudomorphs... [ABSTRACT FROM AUTHOR]

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Background: Reduction in cervical cancer incidence and mortality is not only dependant on promoting cervical cancer screening but also on providing appropriate follow-up and treatment of abnormal cervical cytology.Objectives: The objective of this study was to determine variations in guideline adherence for women requiring abnormal cervical cytology follow-up.Subjects: Subjects of the study are women 18 years or older with an abnormal Pap test in 2000 within a large county healthcare system (n = 8,571).Measurements: Guideline adherence was determined by the presence or absence of the appropriate follow-up procedure within an acceptable time interval for each degree of cytological abnormality. Patients with no follow-up studies were deemed to be lost to follow-up.Results: Of study subjects, 18.5% were lost to follow-up care. Of the remaining 6,987 women, 60.3% received optimal care, 9.4% received suboptimal care, and 30.3% received poor care. Follow-up rates were higher for patients with higher degree of cytological abnormality (OR, 1.29, 95% CI, 1.17-1.42), older patients (OR, 1.03, 95% CI, 1.02-1.030) and those receiving the index Pap test at a larger healthcare facility (OR, 1.13; 95% CI, 1.01-1.27). Receiving optimal care was positively correlated with higher degree of cytological abnormality (p < .0001) and larger facility size (p = .002). Regional variations in care demonstrated the largest cluster having the lowest lost to follow-up rate and the most optimal care.Conclusions: A significant number of women with abnormal cervical cytology are receiving less than optimal care. Further studies are required to determine the specific healthcare delivery practices that need to be targeted to improve guideline adherence for follow-up of abnormal cytology. [ABSTRACT FROM AUTHOR]

Gradual solar energetic particle (SEP) events are evidently accelerated by coronal/interplanetary shocks driven by coronal mass ejections. This talk addresses the different factors which determine the composition of the accelerated ions. The first factor is the set of available seed populations including the solar wind core and suprathermal tail, remnant impulsive events from preceding solar flares, and remnant gradual events. The second factor is the fractionation of the seed ions by the injection process, that is, what fraction of the ions are extracted by the shock to participate in diffusive shock acceleration. Injection is a controversial topic since it depends on the detailed electromagnetic structure of the shock transition and the transport of ions in these structured fields, both of which are not well understood or determined theoretically. The third factor is fractionation during the acceleration process, due to the dependence of ion transport in the turbulent electromagnetic fields adjacent to the shock on the mass/charge ratio. Of crucial importance in the last two factors is the magnetic obliquity of the shock. The form of the proton-excited hydromagnetic wave spectrum is also important. Finally, more subtle effects on ion composition arise from the superposition of ion contributions over the time history of the shock along the observer’s magnetic flux tube, and the sequence of flux tubes sampled by the observer. [ABSTRACT FROM AUTHOR]

Context: Previous studies testing continuous quality improvement (CQI) for depression showed no effects. Methods for practices to self-improve depression care performance are needed. We assessed the impacts of evidence-based quality improvement (EBQI), a modification of CQI, as carried out by 2 different health care systems, and collected qualitative data on the design and implementation process.Objective: Evaluate impacts of EBQI on practice-wide depression care and outcomes.Design: Practice-level randomized experiment comparing EBQI with usual care.Setting: Six Kaiser Permanente of Northern California and 3 Veterans Administration primary care practices randomly assigned to EBQI teams (6 practices) or usual care (3 practices). Practices included 245 primary care clinicians and 250,000 patients.Intervention: Researchers assisted system senior leaders to identify priorities for EBQI teams; initiated the manual-based EBQI process; and provided references and tools. EVALUATION PARTICIPANTS: Five hundred and sixty-seven representative patients with major depression.Main Outcome Measures: Appropriate treatment, depression, functional status, and satisfaction.Results: Depressed patients in EBQI practices showed a trend toward more appropriate treatment compared with those in usual care (46.0% vs 39.9% at 6 months, P = .07), but no significant improvement in 12-month depression symptom outcomes (27.0% vs 36.1% poor depression outcome, P = .18). Social functioning improved significantly (mean score 65.0 vs 56.8 at 12 months, P = .02); physical functioning did not.Conclusion: Evidence-based quality improvement had perceptible, but modest, effects on practice performance for patients with depression. The modest improvements, along with qualitative data, identify potential future directions for improving CQI research and practice. [ABSTRACT FROM AUTHOR]

Objective: To describe the variation in provision of hormonal and intrauterine contraception among Veterans Affairs (VA) facilities.Design: Key informant, cross-sectional survey of 166 VA medical facilities. Data from public use data sets and VA administrative databases were linked to facility data to further characterize their contextual environments.Participants: All VA hospital-based and affiliated community-based outpatient clinics delivering services to at least 400 unique women during fiscal year 2000.Measurements: Onsite availability of hormonal contraceptive prescription and intrauterine device (IUD) placement.Results: Ninety-seven percent of facilities offered onsite prescription and management of hormonal contraception whereas 63% offered placement of IUDs. After adjusting for facility caseload of reproductive-aged women, 3 organizational factors were independently associated with onsite IUD placement: (1) onsite gynecologist (adjusted odds ratio [OR], 20.35; 95% confidence interval [CI], 7.02 to 58.74; P<.001); (2) hospital-based in contrast to community-based practice (adjusted OR, 5.49; 95% CI, 1.16 to 26.10; P=.03); and (3) availability of a clinician providing women's health training to other clinicians (adjusted OR, 3.40; 95% CI 1.19 to 9.76; P=.02).Conclusions: VA's provision of hormonal and intrauterine contraception is in accordance with community standards, although onsite availability is not universal. Although contraception is a crucial component of a woman's health maintenance, her ability to obtain certain contraceptives from the facility where she obtains her primary care is largely influenced by the availability of a gynecologist. Further research is needed to determine how fragmentation of women's care into reproductive and nonreproductive services impacts access to contraception and the incidence of unintended pregnancy. [ABSTRACT FROM AUTHOR]