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Layered Security Guidance for Data Asset Management in Additive Manufacturing.

Manufacturing industries are increasingly adopting additive manufacturing (AM) technologies to produce functional parts in critical systems. However, the inherent complexity of both AM designs and AM processes render them attractive targets for cyber-attacks. Risk-based Information Technology (IT) and Operational Technology (OT) security guidance standards are useful resources for AM security practitioners, but the guidelines they provide are insufficient without additional AM-specific revisions. Therefore, a structured layering approach is needed to efficiently integrate these revisions with preexisting IT and OT security guidance standards. To implement such an approach, this paper proposes leveraging the National Institute of Standards and Technology's Cybersecurity Framework (CSF) to develop layered, risk-based guidance for fulfilling specific security outcomes. It begins with an in-depth literature review that reveals the importance of AM data and asset management to risk-based security. Next, this paper adopts the CSF asset identification and management security outcomes as an example for providing AM-specific guidance and identifies the AM geometry and process definitions to aid manufacturers in mapping data flows and documenting processes. Finally, this paper uses the Open Security Controls Assessment Language to integrate the AM-specific guidance together with existing IT and OT security guidance in a rigorous and traceable manner. This paper's contribution is to show how a risk-based layered approach enables the authoring, publishing, and management of AM-specific security guidance that is currently lacking. The authors believe implementation of the layered approach would result in value-added, non-redundant security guidance for AM that is consistent with the preexisting guidance.

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Open Access
The Effects of Channel Supplies on Overall Film-Cooling Effectiveness

Abstract Cooling components in the hot section of a gas turbine are essential to component durability. Common methods of cooling include rib turbulators in internal passages and film cooling on external surfaces. The holes that produce the film cooling are fed from the internal channels often containing ribs. Consequently, there is an interdependence of internal heat transfer and external film cooling. The purpose of this study was to obtain a better understanding of the interaction of ribs and film cooling. To quantify the cooling performance, the surface temperatures were measured, from which overall effectiveness was calculated. For the experiments, additively manufactured test coupons were made of Inconel 718 to match engine Biot numbers. These test coupons had internal feed channels with and without ribs and had both cylindrical holes and meter-diffuser-shaped holes with 15 deg lateral expansion angles and a 1 deg forward expansion angle. A single rectangular channel was one type of feed channel. The other type of feed channel was individual circular channels, with each circular channel supplying an individual film-cooling hole. The experimental results showed that the circular individual channels have 80% higher baseline overall effectiveness than the single rectangular channels without any film cooling. Ribbed turbulators without film cooling also increased the overall effectiveness by 21% for single rectangular channels and by 29% for the circular individual channels compared to the respective non-ribbed channels. While the film cooling increased the overall effectiveness of all geometries, the single rectangular channels had increased overall effectiveness levels by up to twice that of the no film-cooling case. On average, the single rectangular channels had an 80% improvement from film cooling, whereas the individual channel feeds, on average, had only a 50% improvement, given their high baseline effectiveness levels.

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Reproductive outcomes following contraceptive discontinuation for method-related reasons: An analysis of 49 Demographic and Health Surveys.

Contraceptive discontinuation for method-related reasons is a common experience in low- and middle-income countries (LMICs) and may heighten women's risk of unintended pregnancy. Few studies have provided a comprehensive assessment of reproductive outcomes following contraceptive discontinuation in LMICs over the last decade. Using cross-sectional data from 49 Demographic and Health Surveys, we applied competing risks estimation to calculate monthly probabilities of contraceptive resumption and pregnancy over a 12-month period among pooled, regional, and country-specific samples of women who discontinued contraception for method-related reasons (corresponding to 174,726 episodes of discontinuation). We also examined the pregnancy intention status of births/current pregnancies among those who became pregnant in the 12 months following contraceptive discontinuation for method-related reasons. In the pooled sample, the three-month probability of pregnancy and resumption of contraceptive use was 12% and 47%, respectively; by 12 months these probabilities increased to 22% and 55%, respectively. Country-specific analyses show that the probabilities of resuming contraception by three months ranged from 15% in Liberia, Mali, and Sierra Leone to 85% in Bangladesh. On average, the majority of pregnancies/births that occured following discontinuation for method-related reasons were subsequently reported as unintended. However, reports varied depending on when women became pregnant within the 12 months following discontinuation. Our findings suggest the need for more nuanced measures of contraceptive use dynamics-including measures that distinguish between women who resume use of contraception from women who remain at risk of pregnancy in the short period after discontinuation-to better inform specific policies and interventions, particularly aimed at those who remain at risk of pregnancy.

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Open Access
One Hundred Priority Questions for the Development of Sustainable Food Systems in Sub-Saharan Africa

Sub-Saharan Africa is facing an expected doubling of human population and tripling of food demand over the next quarter century, posing a range of severe environmental, political, and socio-economic challenges. In some cases, key Sustainable Development Goals (SDGs) are in direct conflict, raising difficult policy and funding decisions, particularly in relation to trade-offs between food production, social inequality, and ecosystem health. In this study, we used a horizon-scanning approach to identify 100 practical or research-focused questions that, if answered, would have the greatest positive impact on addressing these trade-offs and ensuring future productivity and resilience of food-production systems across sub-Saharan Africa. Through direct canvassing of opinions, we obtained 1339 questions from 331 experts based in 55 countries. We then used online voting and participatory workshops to produce a final list of 100 questions divided into 12 thematic sections spanning topics from gender inequality to technological adoption and climate change. Using data on the background of respondents, we show that perspectives and priorities can vary, but they are largely consistent across different professional and geographical contexts. We hope these questions provide a template for establishing new research directions and prioritising funding decisions in sub-Saharan Africa.

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Open Access
Stop or Switch: Correlates of Stopping Use or Switching Contraceptive Methods While Wanting to Avoid Pregnancy in 48 Low- and Middle-Income Countries.

Contraceptive discontinuation for method-related reasons, while presumably wanting to avoid pregnancy, is a common phenomenon and can contribute to high levels of unmet need and unplanned pregnancies. Some women discontinue contraceptive use and do not quickly resume a method ("stopping"), while others are able to quickly switch to another method to achieve their reproductive goal of avoiding pregnancy ("switching"). We use Demographic and Health Survey data from 48 countries to examine what differentiates women who were able to switch to another method versus those who ultimately stopped entirely, among women who discontinued contraception for method-related reasons. Results show that wanting to limit births, having ever been married, and recent prior use are all associated with switching versus stopping. In addition, we find that women in West and Middle Africa were more likely to stop use compared to women in other regions. Addressing obstacles to contraceptive continuation, including effective method switching, among women who wish to delay or avoid pregnancy should be a priority for global and country initiatives aiming to deliver client-centered care that supports women and couples to make their best family planning choices.

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Sexual health indicators for the United States: Measuring progress and documenting public health needs.

Today, we are facing increased and continued adverse sexual health outcomes in the United States, including high post-COVID-19 pandemic rates of sexually transmitted infections (STIs). For the past 20 years, there have been calls for a national health strategy and a more comprehensive sexual health approach to address the myriad of persistent sexual health problems in this country. Employing a sexual health approach requires shifting from a longstanding, stigmatizing focus on morbidity toward a holistic and integrated focus on health rather than disease. While strategies are being implemented by multisectoral stakeholders, it is also important to establish a core set of indicators that broadly describe the state of sexual health in the U.S. and allow for measurement across time. The development of a comprehensive scorecard with key sexual health indicators has been proposed by other entities (e.g., Public Health England, World Health Organization), but such an attempt has not been made in the U.S. A review of national U.S. surveys and surveillance systems with items related to sexual health was conducted for years 2010-2022 to develop an inventory of existing data that yield national estimates for potential indicators of sexual health. We selected 23 sexual health indicators in four broad domains including: (1) knowledge; communication and attitudes (five indicators); (2) behaviors and relationships (four indicators); (3) service access and utilization (seven indicators); and (4) adverse health outcomes (seven indicators). Recent data for each indicator are provided. A growing body of evidence shows the positive effects of moving away from a morbidity focus toward an integrated, health-promoting approach to sexual health. Yet, not much has been done in terms of how we implement this national shift. We argue that measurement and monitoring are key to future change. We envision these core sexual health indicators would be published in the form of an index that is publicly available and updated frequently. These sexual health indicators could be used for ongoing monitoring, and to guide related research, programming, and policy development to help promote sexual health in coming years.

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Open Access