To explore factors associated with occupational sex segregation in the United States over the past four decades, we analyzed U.S. Bureau of Labor Statistics data for the percent of women employed in ...60 varied occupations from 1972 to 2010. Occupations were assessed on status, people-things orientation, and data-ideas orientation. Multilevel linear modeling (MLM) analyses showed that women increasingly entered high-status occupations from 1972 to 2010, but women's participation in things-oriented occupations (e.g., STEM fields and mechanical and construction trades) remained low and relatively stable. Occupations' data-ideas orientation was not consistently related to sex segregation. Because of women's increased participation in high-status occupations, occupational status became an increasingly weak predictor of women's participation rates in occupations, whereas occupations' people-things orientation became an increasingly strong predictor over time. These findings are discussed in relation to theories of occupational sex segregation and social policies to reduce occupational sex segregation.
Metrological traceability to common references supports the comparability of chemical measurement results produced by different analysts, at various times, and at separate places. Ideally, these ...references are realizations of base units of the International System of Units (SI). ISO/IEC 17025 (Clause 6.5) states that traceability of measurement results is a necessary attribute of analytical laboratory competence, and as such, has become compulsory in many industries, especially clinical diagnostics and healthcare. Historically, claims of traceability for organic chemical measurements have relied on calibration chains anchored on unique reference materials with linkage to the SI that is tenuous at best. A first-of-its-kind National Institute of Standards and Technology (NIST) reference material, ultrapure and extensively characterized PS1 Benzoic Acid Primary Standard for quantitative NMR (qNMR), serves as a definitive, primary reference (calibrant) that assuredly links the qNMR spectroscopy technique to SI units. As qNMR itself is a favorable method for accurate, direct characterization of chemical reference materials, PS1 is a standard for developing other traceable standards and is intended to establish traceability for the measurement of thousands of organic chemical species. NIST PS1 will play a critical role in directly promoting accuracy and worldwide comparability of measurement results produced by the chemical measurement community, supporting the soundness of clinical diagnostics, food safety and labeling, forensic investigation, drug development, biomedical research, and chemical manufacturing. Confidence in this link to the SI was established through (i) unambiguous identification of chemical structure; (ii) determinations of isotopic composition and molecular weight; (iii) evaluation of the respective molecular amount by multiple primary measurement procedures, including qNMR and coulometry; and (iv) rigorous evaluation of measurement uncertainty using state-of-the-art statistical methods and measurement models.
BBC Internet survey participants (119,733 men and 98,462 women) chose from a list of 23 traits those they considered first, second, and third most important in a relationship partner. Across all ...participants, the traits ranked most important were: intelligence, humor, honesty, kindness, overall good looks, face attractiveness, values, communication skills, and dependability. On average, men ranked good looks and facial attractiveness more important than women did (d = 0.55 and 0.36, respectively), whereas women ranked honesty, humor, kindness, and dependability more important than men did (ds = 0.23, 0.22, 0.18, and 0.15). Sexual orientation differences were smaller than sex differences in trait rankings, but some were meaningful; for example, heterosexual more than homosexual participants assigned importance to religion, fondness for children, and parenting abilities. Multidimensional scaling analyses showed that trait preference profiles clustered by participant sex, not by sexual orientation, and by sex more than by nationality. Sex-by-nation ANOVAs of individuals' trait rankings showed that sex differences in rankings of attractiveness, but not of character traits, were extremely consistent across 53 nations and that nation main effects and sex-by-nation interactions were stronger for character traits than for physical attractiveness. United Nations indices of gender equality correlated, across nations, with men's and women's rankings of character traits but not with their rankings of physical attractiveness. These results suggest that cultural factors had a relatively greater impact on men's and women's rankings of character traits, whereas biological factors had a relatively greater impact on men's and women's rankings of physical attractiveness.
The unavailability of appropriate quality assurance/quality control materials in many lipidomics applications poses a significant challenge for lipidomics research. It is recommended that samples ...with certified values and/or consensus estimates, such as NIST SRM 1950–Metabolites in Frozen Human Plasma, be implemented in routine analyses to enable community-wide comparisons of lipidomics results and analytical workflows. Herein, we applied a nontargeted lipidomics method for the analysis of a new human plasma reference material suite developed by NIST (hypertriglyceridemic, diabetic, and African-American plasma pools), in addition to SRM 1950. We identified specific lipidomics fingerprints associated with each sample type, including lauric acid–containing lipids and elevated triacylglycerol levels in hypertriglyceridemic plasma, palmitoleic acid–containing lipids in diabetic plasma, and oxidized fatty acid–containing phospholipids in African-American plasma. This work highlights the importance of developing and profiling application-specific reference materials, while establishing reference data that may be used for system suitability and/or quality control metrics.
Graphical abstract
Introduction
The metabolomics quality assurance and quality control consortium (mQACC) is enabling the identification, development, prioritization, and promotion of suitable reference materials (RMs) ...to be used in quality assurance (QA) and quality control (QC) for untargeted metabolomics research.
Objectives
This review aims to highlight current RMs, and methodologies used within untargeted metabolomics and lipidomics communities to ensure standardization of results obtained from data analysis, interpretation and cross-study, and cross-laboratory comparisons. The essence of the aims is also applicable to other ‘omics areas that generate high dimensional data.
Results
The potential for game-changing biochemical discoveries through mass spectrometry-based (MS) untargeted metabolomics and lipidomics are predicated on the evolution of more confident qualitative (and eventually quantitative) results from research laboratories. RMs are thus critical QC tools to be able to assure standardization, comparability, repeatability and reproducibility for untargeted data analysis, interpretation, to compare data within and across studies and across multiple laboratories. Standard operating procedures (SOPs) that promote, describe and exemplify the use of RMs will also improve QC for the metabolomics and lipidomics communities.
Conclusions
The application of RMs described in this review may significantly improve data quality to support metabolomics and lipidomics research. The continued development and deployment of new RMs, together with interlaboratory studies and educational outreach and training, will further promote sound QA practices in the community.
As feedstocks transition from conventional oil to unconventional petroleum sources and biomass, it will be necessary to determine whether a particular fuel or fuel blend is suitable for use in ...engines. Certifying a fuel as safe for use is time-consuming and expensive and must be performed for each new fuel. In principle, suitability of a fuel should be completely determined by its chemical composition. This composition can be probed through use of detailed analytical techniques such as gas chromatography–mass spectroscopy (GC–MS). In traditional analysis, chromatograms would be used to determine the details of the composition. In the approach taken in this paper, the chromatogram is assumed to be entirely representative of the composition of a fuel, and is used directly as the input to an algorithm in order to develop a model that is predictive of a fuel’s suitability. When a new fuel is proposed for service, its suitability for any application could then be ascertained by using this model to compare its chromatogram with those of the fuels already known to be suitable for that application.
In this paper, we lay the mathematical and informatics groundwork for a predictive model of hydrocarbon properties. The objective of this work was to develop a reliable model for unsupervised classification of the hydrocarbons as a prelude to developing a predictive model of their engine-relevant physical and chemical properties. A set of hydrocarbons including biodiesel fuels, gasoline, highway and marine diesel fuels, and crude oils was collected and GC–MS profiles obtained. These profiles were then analyzed using multi-way principal components analysis (MPCA), principal factors analysis (PARAFAC), and a self-organizing map (SOM), which is a kind of artificial neural network. It was found that, while MPCA and PARAFAC were able to recover descriptive models of the fuels, their linear nature obscured some of the finer physical details due to the widely varying composition of the fuels. The SOM was able to find a descriptive classification model which has the potential for practical recognition and perhaps prediction of fuel properties.
A diverse U.S. sample comprising 1437 men and 1474 women was assessed on sexual orientation, masculinity–femininity of occupational preferences (MF-Occ), self-ascribed masculinity–femininity ...(Self-MF), Big Five personality traits, sex drive, and sociosexuality (positive attitudes toward uncommitted sex). Discriminant analyses explored which traits best distinguished self-identified heterosexual, bisexual, and homosexual individuals within each sex. These analyses correctly classified the sexual orientation of 55% of men and 60% of women, which was substantially better than a chance rate (33%) of assigning participants to one of three groups. For men, MF-Occ and Self-MF distinguished heterosexual, bisexual, and gay men, with heterosexual men most gender typical, gay men most gender atypical, and bisexual men intermediate. Independently, higher sex drive, sociosexuality, and neuroticism and lower conscientiousness distinguished bisexual men from other groups. For women, gender-related interests and Self-MF distinguished lesbians from other groups, with lesbians most gender atypical. Independently, higher sociosexuality, sex drive, and Self-MF distinguished non-heterosexual from heterosexual women. These findings suggest that variations in self-reported sexual orientation may be conceptualized in terms of two broad underlying individual difference dimensions, which differ somewhat for men and women: one linked to gender typicality versus gender atypicality and the other linked to sex drive, sociosexuality, and various personality traits.
Introduction
To date, there has been little effort to develop standards for metabolome-based gut microbiome measurements despite the significant efforts toward standard development for DNA-based ...microbiome measurements.
Objectives
The National Institute of Standards and Technology (NIST), The BioCollective (TBC), and the North America Branch of the International Life Sciences Institute (ILSI North America) are collaborating to extend NIST’s efforts to develop a Human Whole Stool Reference Material for the purpose of method harmonization and eventual quality control.
Methods
The reference material will be rationally designed for adequate quality assurance and quality control (QA/QC) for underlying measurements in the study of the impact of diet and nutrition on functional aspects of the host gut microbiome and relationships of those functions to health. To identify which metabolites deserve priority in their value assignment, NIST, TBC, and ILSI North America jointly conducted a workshop on September 12, 2019 at the NIST campus in Gaithersburg, Maryland. The objective of the workshop was to identify metabolites for which evidence indicates relevance to health and disease and to decide on the appropriate course of action to develop a fit-for-purpose reference material.
Results
This document represents the consensus opinions of workshop participants and co-authors of this manuscript, and provides additional supporting information. In addition to developing general criteria for metabolite selection and a preliminary list of proposed metabolites, this paper describes some of the strengths and limitations of this initiative given the current state of microbiome research.
Conclusions
Given the rapidly evolving nature of gut microbiome science and the current state of knowledge, an RM (as opposed to a CRM) measured for multiple metabolites is appropriate at this stage. As the science evolves, the RM can evolve to match the needs of the research community. Ultimately, the stool RM may exist in sequential versions. Beneficial to this evolution will be a clear line of communication between NIST and the stakeholder community to ensure alignment with current scientific understanding and community needs.
The ratio of index and ring finger lengths (2D:4D) is thought to be a marker of prenatal androgen exposure. In a sample of over 2,000 participants, men had significantly lower 2D:4D ratios than women ...(
d
=.36 and.23 for right and left hands, respectively), and these results were consistent across ethnic groups. Heterosexual men had significantly lower (more male typical) 2D:4D ratios than gay men (
d
=.32 and.31 for right and left hands, respectively), and these results tended to be consistent across ethnic groups. Heterosexual and lesbian women showed no significant differences in 2D:4D ratios, after ethnicity was taken into account. The current findings add to evidence that prenatal hormonal factors may be linked to men's sexual orientation.