Formation of Methane Hydrate in the Presence of Natural and Synthetic Nanoparticles.

Natural gas hydrates occur widely on the ocean-bed and in permafrost regions, and have potential as an untapped energy resource. Their formation and growth, however, poses major problems for the energy sector due to their tendency to block oil and gas pipelines, whereas their melting is viewed as a potential contributor to climate change. Although recent advances have been made in understanding bulk methane hydrate formation, the effect of impurity particles, which are always present under conditions relevant to industry and the environment, remains an open question. Here we present results from neutron scattering experiments and molecular dynamics simulations that show that the formation of methane hydrate is insensitive to the addition of a wide range of impurity particles. Our analysis shows that this is due to the different chemical natures of methane and water, with methane generally excluded from the volume surrounding the nanoparticles. This has important consequences for our understanding of the mechanism of hydrate nucleation and the design of new inhibitor molecules.

Genetic Evidence for Modifying Oceanic Boundaries Relative to Fiji.

We present the most comprehensive genetic characterization to date of five Fijian island populations: Viti Levu, Vanua Levu, Kadavu, the Lau Islands, and Rotuma, including nonrecombinant Y (NRY) chromosome and mitochondrial DNA (mtDNA) haplotypes and haplogroups. As a whole, Fijians are genetically intermediate between Melanesians and Polynesians, but the individual Fijian island populations exhibit significant genetic structure reflecting different settlement experiences in which the Rotumans and the Lau Islanders were more influenced by Polynesians, and the other Fijian island populations were more influenced by Melanesians. In particular, Rotuman and Lau Islander NRY chromosomal and mtDNA haplogroup frequencies and Rotuman mtDNA hypervariable segment 1 region haplotypes more closely resemble those of Polynesians, while genetic markers of the other populations more closely resemble those of the Near Oceanic Melanesians. Our findings provide genetic evidence supportive of modifying regional boundaries relative to Fiji, as has been suggested by others based on a variety of nongenetic evidence. Specifically, for the traditional Melanesia/Polynesia/Micronesia scheme, our findings support moving the Melanesia-Polynesia boundary to include Rotuma and the Lau Islands in Polynesia. For the newer Near/Remote Oceania scheme, our findings support keeping Rotuma and the Lau Islands in Remote Oceania and locating the other Fijian island populations in an intermediate or "Central Oceania" region to better reflect the great diversity of Oceania.

Genetic structure among Fijian island populations.

We examined nine Y chromosome short tandem repeats (Y-STRs) and the mitochondrial DNA (mtDNA) hypervariable segment 1 region in the Fijian island populations of Viti Levu, Vanua Levu, Kadavu, the Lau islands and Rotuma. We found significant genetic structure among these populations for the Y-STRs, both with and without the Rotumans, but not for the mtDNA. We also found that all five populations exhibited the sex-biased admixture associated with areas settled by Austronesian-speaking people, with paternal lineages more strongly associated with Melanesian populations and maternal lineages more strongly associated with Polynesian populations. We also found that the Rotumans in the north and the Lau Islanders in the east were genetically more similar to Polynesian populations than were the other Fijians, but only for the mtDNA. For the Y-STRs, the Rotumans and the Lau Islanders were genetically as similar to Melanesian populations as were the other three populations. Of the five populations, the Rotumans were the most different in almost every regard. Although past genetic studies treated the Fijians as being genetically homogenous despite known geographic, phenotypic, cultural and linguistic variation, our findings show significant genetic variation and a need for a closer examination of individual island populations within Fiji, particularly the Rotumans, in order to better understand the process of the peopling of Fiji and of the surrounding regions.

Safety of aspiration abortion performed by nurse practitioners, certified nurse midwives, and physician assistants under a California legal waiver.

OBJECTIVES: We examined the impact on patient safety if nurse practitioners (NPs), certified nurse midwives (CNMs), and physician assistants (PAs) were permitted to provide aspiration abortions in California. METHODS: In a prospective, observational study, we evaluated the outcomes of 11 487 early aspiration abortions completed by physicians (n = 5812) and newly trained NPs, CNMs, and PAs (n = 5675) from 4 Planned Parenthood affiliates and Kaiser Permanente of Northern California, by using a noninferiority design with a predetermined acceptable risk difference of 2%. All complications up to 4 weeks after the abortion were included. RESULTS: Of the 11 487 aspiration abortions analyzed, 1.3% (n = 152) resulted in a complication: 1.8% for NP-, CNM-, and PA-performed aspirations and 0.9% for physician-performed aspirations. The unadjusted risk difference for total complications between NP-CNM-PA and physician groups was 0.87 (95% confidence interval [CI] = 0.45, 1.29) and 0.83 (95% CI = 0.33, 1.33) in a propensity score-matched sample. CONCLUSIONS: Abortion complications were clinically equivalent between newly trained NPs, CNMs, and PAs and physicians, supporting the adoption of policies to allow these providers to perform early aspirations to expand access to abortion care.

Where we are today: prioritizing women's health services and health policy. A report by the Women's Health Expert Panel of the American Academy of Nursing.

There has been a recent resurgence of interest in women's health as evidenced by several federal and international policy-shaping reports that will impact women's health services. These reports include the 2010 Affordable Care Act, the formation of the National Prevention Council and Strategy, the 2011 IOM report on clinical preventives services for women, and the World Health Organization strategic plan for 2010-2015. In this paper, we summarize and discuss these reports and discuss implications of enacting the suggested health policies. We highlight policy strategies and recommendations that will extend national and global recommendations to improve women's health and wellness across the lifespan and emphasize the urgent need for preventive services. We conclude this paper by detailing our broad recommendations for putting prevention into practice illustrated by specific recommendations related to unintended pregnancy prevention and management.

Modifying the adsorption properties of anionic surfactants onto hydrophilic silica using the pH dependence of the polyelectrolytes PEI, ethoxylated PEI, and polyamines.

The manipulation of the adsorption of the anionic surfactant, sodium dodecyl sulfate, SDS, onto hydrophilic silica by the polyelectrolytes, polyethyleneimine, PEI, ethoxylated PEI, and the polyamine, pentaethylenehexamine, has been studied using neutron reflectometry. The adsorption of a thin PEI layer onto hydrophilic silica promotes a strong reversible adsorption of the SDS through surface charge reversal induced by the PEI at pH 7. At pH 2.4, a much thicker adsorbed PEI layer is partially swelled by the SDS, and the SDS adsorption is now no longer completely reversible. At pH 10, there is some penetration of SDS and solvent into a thin PEI layer, and the SDS adsorption is again not fully reversible. Ethoxylation of the PEI (PEI-EO(1) and PEI-EO(7)) results in a much weaker and fragile PEI and SDS adsorption at both pH 3 and pH 10, and both polymer and surfactant desorb at higher surfactant concentrations (>critical micellar concentration, cmc). For the polyamine, pentaethylenehexamine, adsorption of a layer of intermediate thickness is observed at pH 10, but at pH 3, no polyamine adsorption is evident; and at both pH 3 and pH 10, no SDS adsorption is observed. The results presented here show that, for the amine-based polyelectrolytes, polymer architecture, molecular weight, and pH can be used to manipulate the surface affinity for anionic surfactant (SDS) adsorption onto polyelectrolyte-coated hydrophilic silica surfaces.

The relationship of two types of trauma exposure to current physical and psychological symptom distress in a community sample of Colombian women: why interpersonal violence deserves more attention.

Our purpose in this study was to examine the relationship between interpersonal violence and background traumas and symptom distress in a community sample of Colombian women (N = 217). We utilized the Life Stressor Checklist-Revised (LSC-R) to measure lifetime interpersonal violence (IPV) and background trauma exposure and the Brief Symptom Inventory (BSI) to measure current symptom distress. Although both exposures were common in this sample, IPV was strongly correlated with current symptom distress; background traumas made no unique contribution to the variance in current symptom distress. Based on our findings, it is suggested that interpersonal events may be particularly distressing.

Training in aspiration abortion care: An observational cohort study of achieving procedural competence.

BACKGROUND: Studies in multiple countries have found that the provision of aspiration abortion care by trained nurses, midwives, and other front-line health care workers is safe and acceptable to women. In the United States, most state abortion laws restrict the provision of abortion to physicians; nurse practitioners, nurse-midwives, and physician assistants, can legally perform medication abortion in only twelve states and aspiration abortion in five. Expansion of abortion care by these providers, consistent with their scopes of practice, could help alleviate the increasing difficulty of accessing abortion care in many states. OBJECTIVES: This study used a competency-based training model to teach advanced practice clinicians to perform vacuum aspiration for the abortion care. Previous research reporting on the training of providers other than physicians primarily focused on numbers of procedures performed, without assessment of skill competency or clinician confidence. DESIGN: In this prospective, observational cohort study, advanced practice clinician trainees were recruited from 23 clinical sites across six partner organizations. Trainees participated in a standardized, competency-based didactic and clinical training program in uterine aspiration for first-trimester abortion. SETTINGS: Trainee clinicians needed to be employed by one of the six partner organizations and have an intention to remain in clinical practice following training. PARTICIPANTS: California-licensed advanced practice clinicians were eligible to participate in the training if they had at least 12 months of clinical experience, including at least three months of medication abortion provision, and certification in Basic Life Support. METHODS: A standardized, competency-based training program consisting of both didactic and clinical training in uterine aspiration for first-trimester abortion was completed by 46 advanced practice clinician participants. Outcomes related to procedural safety and to the learning process were measured between August 2007 and December 2013, and compared to those of resident physician trainees. RESULTS: Essentially identical odds of complications occurring from advanced practice clinician-performed procedures were not significantly different than the odds of complications occurring from resident-performed procedures (OR: 0.99; CI: 0.46-2.02; p > 0.05) after controlling for patient sociodemographic and medical history. The number of training days to foundational competence ranged from six to 10, and the number of procedures to competence for those who completed training ranged from 40 to 56 (median = 42.5). CONCLUSIONS: A standardized, competency-based trainingprogram can prepare advanced practice clinicians to safely provide first-trimester aspiration abortions. Access to safe abortion care can be enhanced by increasing the number of providers from cadres of clinicians other than physicians.

Multiple Unintended Pregnancies in U.S. Women: A Systematic Review.

BACKGROUND: Each year, nearly one-half of all pregnancies in the United States are unintended. Risk factors of unintended pregnancy have been studied without attention to whether the pregnancy was the woman's first unintended pregnancy or whether she had had more than one. Little is known about the prevalence, incidence, and risk factors for multiple unintended pregnancies. The purpose of this paper is to present a systematic review of the extant literature on the risk factors for multiple unintended pregnancies in women in the United States, and whether these factors are specific to multiple unintended pregnancies. METHODS: PubMed, PsychInfo, CINAHL, Web of Science, and JSTOR databases were searched for empirical research studies performed after 1979, in the United States, with a primary outcome of multiple unintended pregnancies. Articles that did not establish the intendedness of the studied pregnancies were excluded. RESULTS: Seven studies were identified. For multiple unintended pregnancies, incidence rates ranged from 7.4 to 30.9 per 100 person-years and prevalence rates ranged from 17% to 31.6%. Greater age; identifying as Black or Hispanic; nonvoluntary first intercourse, particularly at a young age; sex trade involvement; and previous abortion were found to be associated with multiple unintended pregnancies. Use of intrauterine devices or combined oral contraceptives were found to decrease the risk of multiple unintended pregnancies. CONCLUSIONS: This review suggests a small number of modifiable factors that may be used to better predict and manage multiple unintended pregnancies.

Role of Insurance Coverage in Contraceptive Use After Abortion.

OBJECTIVE: To assess postaspiration abortion contraceptive use and the role of insurance coverage for abortion in a state that covers abortion and contraception for low-income women. METHODS: This is a secondary analysis of a previously published prospective study to assess the safety of abortion provision. From 2007 through 2013, women seeking first-trimester aspiration abortion were recruited at 25 clinical facilities within four Planned Parenthood affiliates and Kaiser Permanente of Northern California. Patients' medical charts were reviewed to assess the contraceptive methods received on the day of the abortion. A 4-week follow-up survey assessed contraceptive use and contraceptive-related incidents. Primary outcomes included leaving with any method on the day of the abortion and use of any method at the 4-week assessment. Secondary outcomes included intrauterine device or implant use on the day of the procedure and at 4 weeks and switching to a less effective method at 4 weeks. RESULTS: A total of 19,673 women agreed to participate, and 13,904 (71%) completed the 4-week follow-up survey. Ninety-four percent (18,486/19,673) left their abortion visit with a contraceptive method: 21% (4,111/19,673) with an intrauterine device, implant, or permanent method. By the 4-week survey, 8% (1,135/13,904) switched from a high- or medium-efficacy method to a low-efficacy or no method; 0.4% (60/13,904) experienced a contraceptive incident. In adjusted regression analyses, women who paid for the abortion with Medicaid were significantly more likely to use any method (adjusted odds ratio [OR] 3.70, 95% CI 3.09-4.42) or an intrauterine device or implant (adjusted OR 2.14, 95% CI 1.92-2.38) on the day of the abortion than those who did not pay with insurance. Experiencing a contraceptive-related incident was associated with switching to a low-efficacy or no method by the 4-week survey (adjusted OR 3.98, 95% CI 2.20-7.22). CONCLUSION: Insurance coverage for abortion is associated with postabortion contraceptive provision and use, even in settings that cover abortions and contraception for low-income women.

Unintended pregnancy: a framework for prevention and options for midlife women in the US.

Recently unintended pregnancies have been described as "a new kind of mid-life crisis." Given the high prevalence of unwanted or mistimed pregnancy in the US, we examined the sexual and reproductive health patterns of sexually active midlife women. An examination of the prevalence of unintended pregnancy among midlife women revealed a gap in data indicating unmet sexual and reproductive health needs of midlife women. The application of a framework for primary, secondary and tertiary prevention for unintended pregnancy may assist with guiding care for women and identifying implications for reproductive health policy and potential political interference as they relate to sexual and reproductive health in midlife women.

Standardizing the classification of abortion incidents: the Procedural Abortion Incident Reporting and Surveillance (PAIRS) Framework.

OBJECTIVES: To develop and validate standardized criteria for assessing abortion-related incidents (adverse events, morbidities, near misses) for first-trimester aspiration abortion procedures and to demonstrate the utility of a standardized framework [the Procedural Abortion Incident Reporting & Surveillance (PAIRS) Framework] for estimating serious abortion-related adverse events. STUDY DESIGN: As part of a California-based study of early aspiration abortion provision conducted between 2007 and 2013, we developed and validated a standardized framework for defining and monitoring first-trimester (≤14weeks) aspiration abortion morbidity and adverse events using multiple methods: a literature review, framework criteria testing with empirical data, repeated expert reviews and data-based revisions to the framework. RESULTS: The final framework distinguishes incidents resulting from procedural abortion care (adverse events) from morbidity related to pregnancy, the abortion process and other nonabortion related conditions. It further classifies incidents by diagnosis (confirmatory data, etiology, risk factors), management (treatment type and location), timing (immediate or delayed), seriousness (minor or major) and outcome. Empirical validation of the framework using data from 19,673 women receiving aspiration abortions revealed almost an equal proportion of total adverse events (n=205, 1.04%) and total abortion- or pregnancy-related morbidity (n=194, 0.99%). The majority of adverse events were due to retained products of conception (0.37%), failed attempted abortion (0.15%) and postabortion infection (0.17%). Serious or major adverse events were rare (n=11, 0.06%). CONCLUSIONS: Distinguishing morbidity diagnoses from adverse events using a standardized, empirically tested framework confirms the very low frequency of serious adverse events related to clinic-based abortion care. IMPLICATIONS: The PAIRS Framework provides a useful set of tools to systematically classify and monitor abortion-related incidents for first-trimester aspiration abortion procedures. Standardization will assist healthcare providers, researchers and policymakers to anticipate morbidity and prevent abortion adverse events, improve care metrics and enhance abortion quality.

Advanced practice clinicians' interest in providing medical abortion: results of a California survey.

CONTEXT: California's Reproductive Health Privacy Act, which became law in January 2003, clarified that advanced practice clinicians could legally provide medical abortion. Little is known about the characteristics associated with nonphysician clinicians' interest in receiving medical abortion training or their perceptions of barriers to medical abortion provision. METHODS: In early 2003, a total of 1,176 licensed advanced practice clinicians in California-nurse practitioners, physician assistants and certified nurse-midwives-completed a mail-in survey assessing their personal characteristics, beliefs and clinical practices. Weighted univariate and bivariate analyses were conducted to describe the respondents, their interest in receiving medical abortion training and their perceptions of barriers to providing such care. RESULTS: One-quarter of respondents desired training in medical abortion. A higher proportion of nurse-midwives than of nurse practitioners or physician assistants desired training (42% vs. 24% and 23%, respectively). The proportion of respondents desiring training also was elevated among clinicians who have prochoice attitudes, those who are familiar with medical abortion and those who spend at least one-third of their time providing care to women of reproductive age. Lack of training opportunities, legal uncertainties and clinical facility constraints were the most frequently reported perceived barriers to provision of medical abortion. CONCLUSIONS: Considerable proportions of advanced practice clinicians-especially of nurse-midwives-may be interested in receiving medical abortion training. Perceived barriers to providing medical abortion are amenable to change. Policies and programs are needed to ensure that interested, committed clinicians can overcome barriers to providing medical abortion for their patients.