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Solutions to nonlinear boundary value problems modelling physical phenomena in engineering applications have traditionally been approximated using numerical methods. More recently, several semi-analytical methods have been developed and used extensively in diverse engineering applications. This work compares the method of variation of parameters to semi-analytical methods for solving nonlinear boundary value problems arising in engineering. The accuracy and efficiency of the method of variation of parameters are compared to those of two widely used semi-analytical methods, the Adomian decomposition method and the differential transformation method, for three practical engineering boundary value problems: (1) the deflection of a cantilevered beam with a concentrated load, (2) an adiabatic tubular chemical reactor which processes an irreversible exothermal reaction, and (3) the electrohydrodynamic flow of a fluid in an ion drag configuration in a circular cylinder conduit. The accuracy and convergence of each method is investigated using the error remainder function. The method of variation of parameters is significantly more efficient than both the semi-analytical methods and traditional numerical methods while maintaining comparable accuracy. Unlike the semi-analytical methods, the efficiency of variation of parameters is independent of the nonlinearity. Variation of parameters is shown to be an attractive alternative to semi-analytical methods and traditional numerical methods for solving boundary value problems encountered in engineering applications in which solution efficiency is important.

There is an increase in the use of hygrothermal models to complete the performance evaluation of walls assemblies, either in respect to design of new assembles or the retrofit of existing wall assemblies. To this end there are guides available in which is provided information on moisture loads to wall assemblies. This includes, for example, Criteria for Moisture-Control Design Analysis in Buildings given in ASHRAE 160, Assessment of moisture transfer by numerical simulation provided in EN 15026, and NRC’s “Guidelines for Design for Durability of the Building Envelope”. The designer of a new assembly or evaluator of an existing wall is tasked with having to determine what moisture loads to apply to the wall and where to apply this load within the assembly. Typically there is little or no information that is readily available regarding moisture loads to walls and thus the suggested hourly moisture load, as given in ASHRAE 160, is 1% by weight of the total driving rain load to the wall (i.e. kg/m2-hr). In this paper, a brief compendium of water entry test results derived from laboratory tests of various types of wall assemblies is provided from which estimates of moisture loads to different types of wall can be developed. Water entry test results are given of wood frame walls typically used in housing, but also metal-glass curtain walls and other commercial wall assemblies, where possible, in terms of driving loads to the wall.

Abstract Background Studies show that when the Baby Friendly Hospital Initiative (BFHI) is implemented breastfeeding rates increase. However, there are likely to be various barriers to BFHI implementation. This article reports on an empirical study of government-directed BFHI implementation in the New Zealand public hospital system. It focuses primarily on the barriers encountered through implementing the first Two Steps of the BFHI: developing BFHI policy and communicating it to staff; and providing necessary staff training. Methods Qualitative interview data were collected from six lactation consultants. These interviewees emerged via a purposive sample of public hospitals that represent the full range of New Zealand public hospitals. Using a content analysis technique, key themes were drawn from the transcribed interview data. Results Analysis revealed eight themes: the hospitals were in varying stages of BFHI policy development; hospital policy was not necessarily based on government policy; hospital policies were communicated in differing ways and dependent on resources; factors outside of hospital control impacted on capacity to improve breastfeeding rates; and complex organisational matters pose a barrier to educating personnel involved in the birthing process. Conclusion The findings of this study provide empirical support for prior articles about the process of BFHI policy development and implementation. The study also shows that implementation is multi-faceted and complex.

OBJECTIVE: The objective of the study was to compare outcomes between patients who did and did not receive preoperative uterine artery balloon catheters in the setting placenta accreta. STUDY DESIGN: This was a retrospective case-control study of patients with placenta accreta from 1990 to 2011. RESULTS: Records from 117 patients with pathology-proven accreta were reviewed. Fifty-nine patients (50.4%) had uterine artery balloons (UABs) placed preoperatively. The mean estimated blood loss (EBL) was lower (2165 mL vs 2837 mL; P = .02) for the group that had UABs compared with the group that did not. There were more cases with an EBL greater than 2500 mL and massive transfusions of packed red blood cells (>6 units) in the group that did not have UABs. Percreta was diagnosed more often on final pathology in the group with UABs. Surgical times did not differ between the 2 groups. Two patients (3.3%) had complications related to the UABs. CONCLUSION: Preoperative placement of UABs is relatively safe and is associated with a reduced EBL and fewer massive transfusions compared with a group without UABs. [ABSTRACT FROM AUTHOR]

Background: Child health equity is influenced by complex systemic factors, including structural racism, socioeconomic disparities, and access to resources. Traditional public health interventions often target individual behaviors, but there is a growing need for systems approaches that address these root causes. This study examines coalition members' perspectives on promoting child health equity in Milwaukee as a result of participating in an intervention that includes Community-based System Dynamics (CBSD)., Methods: In this case study, we used a mixed-methods approach to describe 10 coalition members' perspective shifts over 6 months, after participating in CBSD activities. These activities generated a causal-loop diagram to map the systemic factors influencing child health. Data collection included pre-post interviews and surveys. The data analysis involved thematic analysis of the qualitative data from interviews, which was then integrated with the open-ended survey responses. The themes identified were cross-referenced with the causal-loop diagram factors to validate and refine the understanding of systemic influences on child health., Results: Post-intervention, coalition members shifted their focus from individual health behaviors to systemic drivers, particularly structural racism and socioeconomic disparities. The causal-loop diagram helped identify leverage points and fostered a readiness for local collective action and policy advocacy., Conclusion: Integrating CBSD into public health coalitions can shift focus from individual behaviors to systemic causes, enabling more effective interventions. This approach offers valuable insights for promoting child health equity through holistic, community-driven strategies and public policy reforms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Greer, Nevels, Meinen, Korth, Moore, Appel, Werner, Calancie, Ellis, Espy, Hendricks, Johnson, Johnson, Nabak, Rembert, Simenz, Weeks, Wilks-Tate and Economos.)

Anthropogenically elevated inputs of nitrogen (N), phosphorus (P), and potassium (K) can affect the carbon (C) budget of nutrient-poor peatlands. Fungi are intimately tied to peatland C budgets due to their roles in organic matter decomposition and symbioses with primary producers; however, the influence of fertilization on peatland fungal composition and diversity remains unclear. Here, we examined the effect of fertilization over 10 years on fungal diversity, composition, and functional guilds along an acrotelm (10-20 cm), mesotelm (30-40 cm), and catotelm (60-70 cm) depth gradient at the Mer Bleue bog, Canada. Simultaneous N and PK additions decreased the relative abundance of ericoid mycorrhizal fungi and increased ectomycorrhizal fungi and lignocellulose-degrading fungi. Fertilization effects were not more pronounced in the acrotelm relative to the catotelm, nor was there a shift toward nitrophilic taxa after N addition. The direct effect of fertilization significantly decreased the abundance of Sphagnum-associated fungi, primarily owing to the overarching role of limiting nutrients rather than a decline in Sphagnum cover. Increased nutrient loading may threaten peatland C stocks if lignocellulose-degrading fungi become abundant and accelerate decomposition of recalcitrant organic matter. Additionally, future changes in plant communities, strong water table fluctuations, and peat subsidence after long-term nutrient loading may also influence fungal functional guilds and depth-dependencies of fungal community structure., (© 2024 John Wiley & Sons Ltd.)

Objective: Developing a better mechanistic and multilevel understanding of sexual violence on college campuses can help us evaluate and implement existing interventions, as well as develop new ones. We brought together scientists, practitioners, and college students to collaboratively characterize the systems surrounding alcohol-involved sexual violence on college campuses. Using collaborative model-building, they created models that highlight interconnected and multilevel influences and consequences of sexual violence., Method: Collaborative model-building activities involved two collaborator groups (twelve students and eight practitioners) and a core modeling team (seven scientists). Each collaborator group met for four two-hour sessions to develop systems models of alcohol use and sexual violence on college campuses. The core modeling team facilitated each session and worked between sessions to ensure the successful development of the model. Specific activities included identifying and prioritizing the causes and consequences of alcohol-involved sexual violence, characterizing the causal relationships between these factors, and developing and modifying causal loop diagrams to illustrate these relationships., Results: Both students and practitioners identified key causes and consequences, including both individual-level (e.g., drinking to intoxication) and campus-level (e.g., institutional support for survivors) constructs. Both groups identified the causal relationships between these variables and identified salient, modifiable mechanisms for reducing alcohol-involved sexual violence., Conclusions: The collaborative model-building process successfully included diverse collaborator voices, integrating influential factors across multiple social-ecological levels. This iterative and capability-building approach can bridge intensive modeling efforts with the implementation and development of more effective sexual violence interventions.

Childhood obesity is a persistent public health concern, and community-based interventions have become crucial for addressing it by engaging local communities and implementing comprehensive evidence-based strategies. The Catalyzing Communities intervention takes a "whole-of-community"approach to involve leaders from diverse sectors in thinking systematically about child healthy weights and implementing evidence-based solutions. Using systems thinking and the Getting to Equity framework to guide interview analysis, this study examines changes in participants' use of systems thinking concepts and health equity in 43 participants across four U.S. communities involved in the Catalyzing Communities intervention. Our findings reveal significant shifts in systems thinking concepts, as participants develop a deeper understanding of childhood obesity as a complex adaptive system, and system insights, as participants increasingly recognize the interconnections and leverage points within the system driving childhood obesity. Participants also experienced increases in health equity thinking and action, particularly when discussing social and structural determinants of health, commitment to targeted actions, and a focus on addressing barriers and enhancing resources. The intersection between systems insights and health equity action, such as explaining leverage points and interventions to reduce deterrents to health behaviors, suggests the need for systems thinking activities to be integrated into health equity planning. Future research is needed to develop measures to connect systems thinking concepts to health equity, and the impact of these to community-level policy, systems, and environmental changes in public health., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Moore et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Overweight and obesity affect 71.2% of adults in the United States, with cancer survivors not far behind at 70.3%. Subgroups such as those diagnosed with acute lymphoblastic leukemia (ALL) face even greater challenges. The Exercise and Quality Diet after Leukemia (EQUAL) trial sought to address weight management issues among ALL survivors by implementing a remotely delivered weight loss intervention, leveraging the previously proven Practice-based Opportunities for Weight Reduction (POWER) program. Despite a strong foundation and design, the EQUAL trial yielded null results. Key differences in study populations and intervention contexts between the EQUAL and POWER trials, such as the lack of primary care physician involvement in EQUAL, contributed to these outcomes. EQUAL's failure to meet its accrual target and poor adherence among participants highlighted challenges in engaging this unique population. Contrary to EQUAL's conclusions, evidence from other studies supports the efficacy of remote interventions for weight loss among cancer survivors. The lack of qualitative assessment among ALL survivors and key integration to inform intervention adaptations undermined EQUAL's impact. However, EQUAL's impressive retention rate offers valuable insights. Lessons from EQUAL underscore the need for well-fitted, remotely delivered interventions and the importance of thoughtfully adapted and tailored approaches to specific survivor populations. See related article by Fiedmann et al., p. 1158., (©2024 American Association for Cancer Research.)

Self-injurious behavior (SIB) among children and youth with developmental disabilities has not diminished in prevalence despite the availability of effective interventions, and the impact on quality of life for people and their families is devastating. The current meta-analysis reviews SIB intervention research between 2011 and 2021 using single-case experimental designs with children and youth up to 21 years old and provides a quantitative synthesis of data from high-quality studies including moderator analyses to determine effects of participant and study characteristics on intervention outcomes. Encouraging findings include a high level of effectiveness across studies in the decrease of SIB (Tau- U  = -0.90) and increase of positive behavior (Tau- U  = 0.73), as well as an increase in studies (relative to prior reviews) reporting intervention fidelity, generalization, maintenance, and social validity. However, our findings shed limited light on potential moderating variables in the development of interventions for children and youth who exhibit SIB. Of the potential moderators of intervention effects, only implementer (researcher/therapist vs. parent/caregiver) and setting (clinic vs. home) were significantly associated with improved outcomes. We discuss the need for more robust involvement of natural communities of implementers in SIB intervention research to better equip them to effectively and sustainably meet the needs of people they care for. We also discuss the importance of creating systems enabling broad access for children with SIB to effective interventions in service of reducing burden for people, families, and society over time., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

There has been a steady increase in people with symptoms of depression over the past several years (since 2011). The further increase in stress and depression in the early part of the COVID-19 pandemic was accompanied by an increase in unmet mental health needs. Many have turned to complementary and alternative medicine (CAM) therapies such as bright-light therapy, yoga, meditation, and dietary supplements like St. John's wort or folic acid. The reliability of evidence for use of CAM therapies for depression has remained low. There are few randomized controlled trials (RCTs) in the current literature and poor methodology in many of the trials that are available. This state of the science review examines current published guidelines, meta-analyses, systematic reviews, and RCTs regarding use of CAM therapies in the management of depression., (© 2023 by the American College of Nurse-Midwives.)

This case study describes the application of a theory-informed, stakeholder-driven intervention with a group of 19 multi-sector stakeholders from an existing coalition to promote whole-of-community change that supports childhood obesity prevention. The intervention applied community-based system dynamics to design and implement activities that promoted insights into the systems driving childhood obesity prevalence and helped participants prioritize actions to influence those systems. This led to three new priority areas for the coalition: addressing food insecurity; building power among historically marginalized voices within the community; and supporting advocacy efforts to promote community-wide change beyond the coalition's previous focus on organizational-level policy, systems and environment change. The intervention spurred the application of community-based system dynamics to other health issues and in partner organizations, which demonstrates paradigm shifts about how to address complex public health issues in the community., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Calancie, Fair, Wills, Werner, Appel, Moore, Hennessy and Economos.)

The acoustic standing wave near the end of an open pipe is investigated using spectrally analyzed high-speed transmission electronic speckle pattern interferometry. It is shown that the standing wave extends beyond the open end of the pipe and the amplitude decays exponentially with distance from the end. Additionally, a pressure node is observed near the end of the pipe in a position that is not spatially periodic with the other nodes in the standing wave. A sinusoidal fit to the amplitude of the standing wave inside the pipe indicates that the end correction is well predicted by current theory., (© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

Ericaceous shrubs adapt to the nutrient-poor conditions in ombrotrophic peatlands by forming symbiotic associations with ericoid mycorrhizal (ERM) fungi. Increased nutrient availability may diminish the role of ERM pathways in shrub nutrient uptake, consequently altering the biogeochemical cycling within bogs. To explore the significance of ERM fungi in ombrotrophic peatlands, we developed the model MWMmic (a peat cohort-based biogeochemical model) into MWMmic-NP by explicitly incorporating plant-soil nitrogen (N) and phosphorus (P) cycling and ERM fungi processes. The new model was applied to simulate the biogeochemical cycles in the Mer Bleue (MB) bog in Ontario, Canada, and their responses to fertilization. MWMmic_NP reproduced the carbon(C)-N-P cycles and vegetation dynamics observed in the MB bog, and their responses to fertilization. Our simulations showed that fertilization increased shrub biomass by reducing the C allocation to ERM fungi, subsequently suppressing the growth of underlying Sphagnum mosses, and decreasing the peatland C sequestration. Our species removal simulation further demonstrated that ERM fungi were key to maintaining the shrub-moss coexistence and C sink function of bogs. Our results suggest that ERM fungi play a significant role in the biogeochemical cycles in ombrotrophic peatlands and should be considered in future modeling efforts., (© 2022 The Authors. New Phytologist © 2022 New Phytologist Foundation.)

A method for imaging an acoustic standing wave in the presence of flowing gas is described. The optical power at the acoustic frequency in each pixel of a series of high-speed transmission electronic speckle pattern interferograms is used to map the steady-state pressure variations of an acoustic standing wave. The utility of the process is demonstrated by imaging the standing wave inside a transparent organ pipe.

Peatlands account for 15 to 30% of the world's soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are known to vary among peatlands contributing to the uncertainty of global C inventories, but there are few global studies that relate peatland classification to peat chemistry. We analyzed 436 peat cores sampled in 24 countries across six continents and measured C, N, and organic matter (OM) content at three depths down to 70 cm. Sites were distinguished between northern (387) and tropical (49) peatlands and assigned to one of six distinct broadly recognized peatland categories that vary primarily along a pH gradient. Peat C and N concentrations, OM content, and C:N ratios differed significantly among peatland categories, but few differences in chemistry with depth were found within each category. Across all peatlands C and N concentrations in the 10-20 cm layer, were 440 ± 85.1 g kg-1 and 13.9 ± 7.4 g kg-1, with an average C:N ratio of 30.1 ± 20.8. Among peatland categories, median C concentrations were highest in bogs, poor fens and tropical swamps (446-532 g kg-1) and lowest in intermediate and extremely rich fens (375-414 g kg-1). The C:OM ratio in peat was similar across most peatland categories, except in deeper samples from ombrotrophic tropical peat swamps that were higher than other peatlands categories. Peat N concentrations and C:N ratios varied approximately two-fold among peatland categories and N concentrations tended to be higher (and C:N lower) in intermediate fens compared with other peatland types. This study reports on a unique data set and demonstrates that differences in peat C and OM concentrations among broadly classified peatland categories are predictable, which can aid future studies that use land cover assessments to refine global peatland C and N stocks., Competing Interests: There are no competing interests, (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Background: A strong body of evidence links young children's intake of sugar-sweetened beverages (SSBs) with myriad negative outcomes., Objectives: Our research provides insight into whether and to what extent potential intervention strategies can reduce young children's consumption of SSBs., Methods: We built an agent-based model (ABM) of SSB consumption representing participants in the Project Viva longitudinal study between ages 2 and 7 y. In addition to extensive data from Project Viva, our model used nationally representative data as well as recent, high-quality literature. We tested the explanatory power of the model through comparison to consumption patterns observed in the Project Viva cohort. Then, we applied the model to simulate the potential impact of interventions that would reduce SSB availability in 1 or more settings or affect how families receive and respond to pediatrician advice., Results: Our model produced age-stratified trends in beverage consumption that closely match those observed in Project Viva cohort data. Among the potential interventions we simulated, reducing availability in the home-where young children spend the greatest amount of time-resulted in the largest consumption decrease. Removing access to all SSBs in the home resulted in them consuming 1.23 (95% CI: 1.21, 1.24) fewer servings of SSBs per week on average between the ages of 2 and 7 y, a reduction of ∼60%. By comparison, removing all SSB availability outside of the home (i.e., in schools and childcare) had a smaller impact (0.77; CI: 0.75, 0.78), a reduction of ∼40%., Conclusions: These results suggest that interventions reducing SSB availability in the home would have the strongest effects on SSB consumption., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Background: While most coalition research focuses on studying the effects of peer relationship structure, this study examines the coevolution of coalition structure and behavior across three communities in the U.S. with the goal of identifying coalition dynamics that impact a childhood obesity prevention intervention.  METHODS: Over two years (2018-2020), three communities within the U.S. participated in a childhood obesity prevention intervention at different times. This intervention was guided by the Stakeholder-Driven Community Diffusion theory, which describes an empirically testable mechanism for promoting community change. Measures are part of the Stakeholder-driven Community Diffusion (SDCD) survey with demonstrated reliability, which include knowledge of and engagement with childhood obesity prevention and social networks. Data from three coalition-committees and their respective networks were used to build three different stochastic actor-oriented models. These models were used to examine the coevolution of coalition structure with coalition behavior (defined a priori as knowledge of and engagement with obesity prevention) among coalition-committee members and their nominated alters (Network A) and coalition-committee members only (Network B).  RESULTS: Overall, coalitions decrease in size and their structure becomes less dense over time. Both Network A and B show a consistent preference to form and sustain ties with those who have more ties. In Network B, there was a trend for those who have higher knowledge scores to increase their number of ties over time. The same trend appeared in Network A but varied based on their peers' knowledge in and engagement with childhood obesity prevention. Across models, engagement with childhood obesity prevention research was not a significant driver of changes in either coalition network structure or knowledge., Conclusions: The trends in coalition Network A and B's coevolution models may point to context-specific features (e.g., ties among stakeholders) that can be leveraged for better intervention implementation. To that end, examining tie density, average path length, network diameter, and the dynamics of each behavior outcome (i.e., knowledge in and engagement with childhood obesity prevention) may help tailor whole-of-community interventions. Future research should attend to additional behavioral variables (e.g., group efficacy) that can capture other aspects of coalition development and that influence implementation, and to testing the efficacy of network interventions after trends have been identified., (© 2022. The Author(s).)

Over the past two decades, sexual and gender minority (SGM) youth health inequities have remained the same or widened, highlighting the need for new approaches to foster health equity. Complex systems science (CSS) techniques must be added to our armamentarium because of the following: CSS techniques can model cyclical feedback loops inherent in the relationships between SGM youth health outcomes and their multilevel causes, thereby enhancing the integration of real-world complexity in scientific models; and CSS can simulate multiple hypothetical interventions, thereby identifying future interventions with great potential impact. We describe four promising CSS techniques for advancing SGM youth health equity.

A method for visualizing the air flow from the mouths of vocalists and wind musical instruments is presented. The method is based on a modification of electronic speckle pattern interferometry that incorporates the interference of a transmitted object beam rather than the standard method using a reflected object beam. The resulting whole-field real-time images are a valuable resource for both scientific and pedagogical use.

Brass wind instruments with long sections of cylindrical pipe, such as trumpets and trombones, sound "brassy" when played at a fortissimo level due to the generation of a shock front in the instrument. It has been suggested that these shock fronts may increase the spread of COVID-19 by propelling respiratory particles containing the SARS-CoV-2 virus several meters due to particle entrainment in the low pressure area behind the shocks. To determine the likelihood of this occurring, fluorescent particles, ranging in size from 10-50 μm, were dropped into the shock regions produced by a trombone, a trumpet, and a shock tube. Preliminary results indicate that propagation of small airborne particles by the shock fronts radiating from brass wind instruments is unlikely.

Recent perspectives on Indigenous health have recognized language, culture, and values as central to well-being and recovery from historical trauma. Health coalitions, which identify community health concerns and mobilize members to implement strategies for change, have begun to shift their focus from programs to policy, systems, and environmental change but have been slower to recognize the possibilities of centering Indigenous ways of being in their work. This article details a case study of the Menominee Wellness Initiative, an Indigenous health coalition that has increasingly made language, culture, and collective values the focus of their health promotion work, and often due to the participation and influence of community organizers in the coalition. The study is presented as a collaborative writing effort between coalition members and academic partners. Qualitative data were gathered through observations of coalition meetings; in-depth, semistructured interviews with coalition members; and interactive data analysis discussions within the collaborative writing team. In the results, we describe how the shift in the coalition's framework came to be and the influence this shift has had on the coalition, its activities, and its community impacts. These findings illustrate and extend understanding of several principles of Collaborating for Equity and Justice and supports literature and practice related to health promotion through the centering of Indigenous ways.

Background: Treating women with gestational diabetes mellitus in the third trimester improves perinatal outcomes. It is unknown whether treating women with mild glucose intolerance earlier in pregnancy would be beneficial in the reduction of maternal and neonatal morbidities., Objective: In women with hyperglycemia (hemoglobin A1c ≥5.7% and/or fasting glucose ≥92 mg/dL) in early pregnancy, we sought to determine whether immediate treatment improved maternal and neonatal outcomes., Study Design: This unblinded randomized controlled trial enrolled women with hyperglycemia at ≤15+0 weeks gestation between 2013 and 2015. Participants were assigned randomly to early pregnancy or third-trimester treatment of hyperglycemia that included nutrition counseling, glucose monitoring, and medications as needed. Participants underwent a blinded 2-hour glucose tolerance test at 24-28 weeks gestation. Exclusion criteria were pregestational diabetes mellitus and multiple gestations. The primary outcome was the proportion of infants with neonatal umbilical cord C-peptide >1.77 nmoL (90th percentile). Secondary outcomes were neonatal fat mass, infant World Health Organization weight-for-length percentile at birth, maternal gestational weight gain, and diagnosis of gestational diabetes mellitus on glucose tolerance test. Mann-Whitney-Wilcoxon test and Fisher's exact test were used, as appropriate., Results: A total of 202 women were assigned randomly; 45 women dropped out before delivery, which left cases 157 for analysis (82 with early pregnancy and 75 with third-trimester treatment). The trial was terminated early because of low enrollment. Baseline characteristics were similar between groups. There was no difference in C-peptide >90th percentile between groups (1 [1.5%] vs 4 [6.7%]; P=.19) in the early pregnancy and third-trimester groups, respectively). There was also no difference in fat mass (0.37±0.16 vs 0.36±0.17 kg; P=.91), weight-for-length percentile at birth (25% vs 25%; P=.46), or macrosomia (1.5 vs 5.0%; P=.84). Maternal gestational weight gain was 22.6±12.9 lb and 23.9±11.2 lb in the early pregnancy and third-trimester groups, respectively (P=.88). Gestational diabetes mellitus was diagnosed in 19.0% of the cohort and did not differ between groups (14.2% vs 25.8%; P=.17)., Conclusion: In this population of women with hyperglycemia, treatment in early pregnancy did not appear to improve maternal or neonatal outcomes significantly. Given comparable results in both groups, caution should be used in the initiation of an intensive diabetes mellitus treatment protocol for women with the diagnosis of hyperglycemia in early gestation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 °C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.

The results of experiments designed to determine the origin of the anomalous frequency components in the sound of the piano commonly referred to as phantom partials are reported. It is shown that these overtones, which occur at the sum and difference frequencies associated with the transverse string motion, are produced by nonlinearities in both the string and the wooden components of the piano. However, the contribution from the string is significantly smaller than the contributions from other components.

Pools are common in northern peatlands but studies have seldom focused on their nutrient biogeochemistry, especially in relation to their morphological characteristics and through seasons. We determined the environmental characteristics controlling carbon (C), nitrogen (N) and phosphorus (P) biogeochemistry in pools and assessed their evolution over the course of the 2016 growing season in a subboreal ombrotrophic peatland of eastern Canada. We showed that water chemistry variations in 62 pools were significantly explained by depth (81.9%) and the surrounding vegetation type (14.8%), but not by pool area or shape. Shallow pools had larger dissolved organic carbon (DOC) and total nitrogen (TN) concentrations and lower pH than deep pools, while pools surrounded by coniferous trees had more recalcitrant DOC than pools where vegetation was dominated by mosses. The influence of depth on pool biogeochemistry was confirmed by the seasonal survey of pools of different sizes with 47.1% of the variation in pool water chemistry over time significantly explained. Of this, 67.3% was explained by the interaction between time and pool size and 32.7% by pool size alone. P concentrations were small in all pools all summer long and combined with high N:P ratios, are indicative of P-limitation. Our results show that pool biogeochemistry is influenced by internal processes and highlight the spatial and temporal heterogeneity of nutrient biogeochemistry in ombrotrophic peatlands., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Nutrient availability is an important control on the vegetation distribution, productivity and functioning of peatland ecosystems and we examined spatial and temporal patterns of nutrient availability through ion exchange at Mer Bleue bog, southeast Ontario, Canada. We installed ion exchange probes at 5-15cm for 4weeks and determined nutrient sorption at undisturbed sites as well as those affected by nitrogen (N), phosphorus (P), potassium (K) fertilization and drainage. Under undisturbed conditions, the bog had very small amount of available nutrients, especially N (ammonium>nitrate) and P, and exhibited small variations in nutrient availability during the growing season (May to October). The increase in NPK availability upon fertilization was short-lived over the season and the stoichiometry of available NPK captured by the probes was mismatched with the vegetation. The increase in nutrient availability with drainage was confounded by substantial changes in vegetation. We compare these results with data from other Canadian bogs and fens to provide baseline data on nutrient availability in peatlands., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Hypertensive disorders of pregnancy are among the leading causes of maternal morbidity and mortality. Studies suggest that the use of folic acid may lower the risk of hypertensive disorders in pregnant women., Aim: The aim of this study was to assess the effects of timing and duration of folic acid-containing supplement use on the risk for gestational hypertension and preeclampsia., Methods: Exposures and outcomes data were obtained through interviews and review of participant's medical records from the MotherToBaby cohort studies across the United States and Canada. Demographics, medical history, lifestyle factors, substance use, and fetal sex were assessed as potential confounders. Unadjusted and adjusted risks for gestational hypertension and preeclampsia were examined using odds ratios and 95% confidence intervals., Findings: 3247 women were included in the study. Compared to non-supplement use, early and late supplement use were not significantly associated with the development of gestational hypertension or preeclampsia. The odds of developing gestational hypertension and preeclampsia were significantly reduced as the duration of folic acid-containing supplement use increased., Conclusion: Findings from this study suggest that the use of folic acid-containing supplements may mitigate the risk for gestational hypertension and preeclampsia., (Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.)

Peatlands are globally significant sources of atmospheric methane (CH 4 ). While several studies have examined the effects of nutrient addition on CH 4 dynamics, there are few long-term peatland fertilization experiments, which are needed to understand the aggregated effects of nutrient deposition on ecosystem functioning. We investigated responses of CH 4 flux and production to long-term field treatments with three levels of N (1.6-6.4 g m -2 yr -1 as NH 4 NO 3 ), potassium and phosphorus (PK, 5.0 g P and 6.3 g K m -2 yr -1 as KH 2 PO 4 ), and NPK in a temperate bog. Methane fluxes were measured in the field from May to August in 2005 and 2015. In 2015 CH 4 flux was higher in the NPK treatment with 16 years of 6.4 g N m -2 yr -1 than in the control (50.5 vs. 8.6 mg CH 4 m -2 d -1 ). The increase in CH 4 flux was associated with wetter conditions derived from peat subsidence. Incubation of peat samples, with and without short-term PK amendment, showed that potential CH 4 production was enhanced in the PK treatments, both from field application and by amending the incubation. We suggest that changes in this bog ecosystem originate from long-term vegetation change, increased decomposition and direct nutrient effects on microbial dynamics.

While considerable attention has been given to the measurement of mercury (Hg) and lead (Pb) concentrations and accumulation in detailed peat cores in central Canada, the geographic distribution and density of sampling are generally limited. Here, we use the Ontario Peatland Inventory to examine broad patterns of Hg and Pb concentration with depth, based on 338 peat cores (containing >1500 analyzed samples) from 127 bogs, fens and swamps located in southeastern, northeastern and northwestern sections of Ontario. Overall, Hg concentrations averaged 0.05 μg g -1 and that of Pb averaged 10.8 μg g -1 . Maximum values in the top 50 cm of the profiles are 0.08 μg g -1 and 26.2 μg g -1 for Hg and Pb, respectively. The ratio between these values (surface) and the values from below 100 cm (background), where peat likely accumulated before 1850 and industrial activities were limited, are 2.3 and 6.6 for Hg and Pb, respectively. The highest surface:background concentration ratios are generally found in the westernmost part of the province and in the southeast for Hg and around areas that are more heavily populated for Pb. Our results show that a vast amount of Hg and Pb are stored in Ontarian peatlands, although the spatial distribution of these stores varies. The rapid decomposition of peat in a changing climate could release these pollutants to the atmosphere., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Phantom partials are anomalous overtones in the spectrum of the piano sound that occur at sum and difference frequencies of the natural overtones of the string. Although they are commonly assumed to be produced by forced longitudinal waves in the string, analysis of the sound of a piano produced by mechanically vibrating the soundboard while all the strings are damped indicates that phantom partials can occur in the absence of string motion. The magnitude of the effect leads to the conclusion that nonlinearity in the non-string components may be responsible for some of the power in the phantom partials.

The objective of the three-year study was to examine spatial and temporal patterns of fluxes and soil pore air concentrations of methane (CH 4 ), carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) from an experimental mass grave located in a temperate environment. The mass grave (5×10m) contained twenty pig carcasses at a depth of approximately 1m was compared to a plot of the same dimensions containing only disturbed soil, as well as an undisturbed plot. Soil pore air CH 4 concentrations were sub-ambient (<1.8ppm) except at 75 and 100cm depths at the mass grave in years 1 and 2 but decreased in year 3. The consumption of CH 4 within the aerobic soil resulted in small negative fluxes at the soil surface. Soil pore air CO 2 concentration showed an increase with depth in all three plots, with the largest increase (>100,000ppm at 1m) in the mass grave, though there was a marked decrease from years 1 to 3. Surface fluxes of CO 2 showed strong seasonal variations, peaking in summer. Soil pore air N 2 O concentration showed major increases in the mass grave, compared to the other two plots with the pattern maintained over the three years, resulting in larger surface fluxes of N 2 O. To establish the role of the carcasses in N 2 O dynamics, we incubated a soil sample containing carcass material which resulted in fast rates of N 2 O production and consumption. The maintenance of elevated pore air concentration and surface flux of N 2 O throughout the 3 years suggests that this is a long-term pattern and likely the best of the three gases to use to detect graves. Thus, we suggest that measurement of soil pore air concentrations, especially of N 2 O, could be a simple and effective approach to help determine the location of clandestine graves., (Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.)

Complementary and alternative medicine (CAM) treatments have been used for thousands of years around the world. There has been increased interest in utilizing CAM for menopausal symptoms since the release of results of the Women's Health Initiative elucidated long-term adverse effects associated with hormone therapy. Women looking for more natural or safer means to treat hot flushes, night sweats, and other menopausal symptoms often turn to CAM such as yoga, phytoestrogens, or black cohosh. Yet there have been few well-conducted studies looking at the efficacy of these treatments. This review examines randomized clinical trials, systematic reviews, and meta-analyses evaluating the effectiveness of commonly used CAM for the treatment of menopausal symptoms., (© 2017 by the American College of Nurse-Midwives.)

Purpose: This study aimed to examine the association between discontinued and continued use of antidepressants and risk for gestational hypertension (GH) and preeclampsia (PE)., Methods: Data from the MotherToBaby pregnancy studies from 2004 to 2014 were analyzed to compare women who discontinued antidepressant use ˂20 weeks of gestation (discontinuers) and women who continued antidepressant use ≥20 weeks of gestation (continuers) to non-users for risk of GH (blood pressure ≥140/90 mmHg on two or more occasions at ≥20 weeks of gestation) and PE (GH with proteinuria). Maternal data, including exposures and study outcomes, were collected through multiple phone interviews. Medical records were used to validate outcomes. Odds ratios (ORs) and 95 % confidence intervals were estimated using logistic regression. Risk for GH and PE were also assessed within antidepressant drug classes., Results: Data from 3471 women were analyzed. Continuers were significantly at risk for GH (adjusted odds ratios (aOR) 1.83; 95 % CI 1.05, 3.21) after adjustment. Analyses by drug class showed that continued use of serotonin-norepinephrine reuptake inhibitors (SNRI) increased risk for GH; however, of the 21 women who continued to use SNRI, only 3 developed GH. Continuers who used two or more antidepressant drug classes had increased risk for PE. Selective serotonin reuptake inhibitors or other antidepressant use was not associated with increased risk for GH or PE. No significant associations with PE or GH were found for discontinuers., Conclusions: Results suggest that women who continued to use antidepressants in the second half of pregnancy are at risk for GH and PE. No significant association was found among discontinuers.

Objective To compare postpartum with preconception insulin doses in well-controlled (HbA1c ≤ 7.4%) type 1 diabetes mellitus (T1DM) and to characterize differences in postpartum insulin dosing based on infant feeding. Study Design The primary outcome in this retrospective cohort was the change in total daily insulin (TDI) from preconception to postpartum. Insulin administration (continuous subcutaneous insulin infusion [CSII] vs. multiple daily injections [MDI]), HbA1c, body mass index (BMI), and infant feeding were abstracted. Results We identified 44 women with T1DM and HbA1c ≤ 7.4%. Preconception mean BMI was 24.6 ± 3.6 kg/m(2) and median (interquartile range [IQR]) HbA1c was 6.4 (6.0-6.9)%. Of these, 73% used CSII and 27% used MDI. Additionally, 80% of patients reported exclusive breastfeeding, 7% were exclusively formula feeding, and 13% used both breast milk and formula. Median (IQR) preconception TDI was 0.64 (0.49-0.69) U/kg/day, and postpartum: 0.39 (0.30-0.50) U/kg/day. Postpartum TDI was 34% lower than preconception TDI (p = 0.02). There was no difference in the postpartum TDI in patients who were breast versus formula feeding or when comparing CSII with MDI. Conclusion There was a significant decrease in the TDI required postpartum when compared with preconception. Dosages do not seem to be impacted by administration route or breastfeeding. These findings warrant consideration when dosing postpartum insulin in patients with T1DM., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Objective: To determine if an excessive rate of gestational weight gain (GWG) in twin pregnancies is associated with adverse obstetric outcomes., Methods: Retrospective cohort study of twin pregnancies delivered at the University of California, San Diego 2001-2014. Women were included if they had adequate or excessive rates of GWG as determined by Institute of Medicine guidelines. Demographic and outcome variables were collected by chart review., Results: Four hundred and eighty-nine twin pregnancies met inclusion criteria. Of which, 40.5% had adequate rates of GWG and 41.5% had excessive rates of GWG. The rates of preterm birth and gestational diabetes were similar between the two groups. Gestational hypertension and preeclampsia were more common in women with excessive GWG (37.9% versus 19.7%; p < 0.01). This finding persisted in multivariate analysis. The mean birth weight percentiles were higher in the excessive GWG group and these women were also less likely to have an infant with a birth weight <10th percentile (21.4% versus 35.9%, p < 0.01)., Conclusions: Excessive GWG is associated with a higher risk for gestational hypertension and preeclampsia, but no other adverse perinatal outcomes. Infants born to mothers with excessive GWG are less likely to be small for gestational age than those born to women with adequate GWG.

Objective: We hypothesized that patients with type 1 diabetes mellitus (T1DM) who were managed during their pregnancy with a continuous subcutaneous insulin infusion (CSII) would have a lower incidence of neonatal hypoglycemia (NH) than patients managed with multiple daily injections (MDI) of insulin., Study Design: This was a retrospective cohort of 95 women with T1DM who delivered singleton, term neonates between 2007 and 2014. The primary outcome was incidence of NH (capillary plasma glucose ≤ 45 mg/dL) in the first 24 hours after birth., Results: The incidence of NH was 66.0% (62/95). The NH rate was significantly higher in women managed with CSII versus MDI (62 vs. 38%, p = 0.024). Neonates with NH had a higher birth weight (3,867 ± 658 vs. 3,414 ± 619 g, p = 0.002). When analyzing intrapartum glucose management, mothers of neonates with NH had significantly less time managed on an insulin infusion (median interquartile range 7 [3.5-30.5] vs. 17.5 [2.0-17.5] hours, p = 0.014). In multivariable analysis, only maternal body mass index (BMI) (p = 0.035) and time on an insulin infusion (p = 0.043) were significantly associated with NH., Conclusion: In our population of patients with T1DM, CSII was more prevalent in the NH group; however, when controlling for other factors, intrapartum glucose management and early maternal BMI were the only variables associated with NH., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Objective: To assess gestational weight gain (GWG) in obese women to determine an inflection point that identifies women at risk for excessive weight gain., Study Design: This is an observational prospective cohort study of pregnancies managed through the UC San Diego Maternal Weight and Wellness Program from 2011 to 2014. The primary outcome was total gestational weight gain. GWG was categorized as inadequate (<11 pounds), adequate (11-20 pounds), and excessive (>20 pounds) based on Institute of Medicine (IOM) recommendations. Other outcomes were GWG by trimester and postpartum weight retention. Bivariate and multivariate analyses were used to assess factors associated with GWG., Results: Ninety-five patients had a mean prepregnancy body mass index (BMI) of 41.9 ± 8.9 kg/m(2) and a net weight gain of 21.9 ± 19 pounds. First trimester GWG was -0.3 ± 4.9 pounds, second trimester was 10.4 ± 10.8 pounds, and third trimester was 11.4 ± 8.5 pounds for all participants. Women who exceeded IOM recommendations accelerated weight gain at 12-14 weeks and gained a majority of weight during the second trimester. Weight gain of more than two pounds at 12-14 weeks had a 96 % positive predictive value (95 % CI 79-99) for excessive GWG. Postpartum women with excessive GWG retained more weight than those with inadequate GWG (10.7 ± 15.6 pounds compared with -13.6 ± 10.9 pounds, P < 0.001). On multiple linear regression GWG by trimester was predictive of total GWG with second and third trimester GWG having the greatest effect on total GWG. Prepregnancy BMI and gestational diabetes were not predictors of total GWG., Conclusions: Obese women at risk for excessive GWG may be identified as early as 12-14 weeks and gain most weight during the second trimester. GWG less than 11 pounds resulted in significant postpartum weight loss among obese women.