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In this article, I examine how the fear of miscegenation developed as a raison d’être for the construction and maintenance of apartheid. I argue that despite its efficacy at reproducing racial-caste formations, miscegenation taboo ultimately undermined its own hegemonic mythology by constructing contradictory erotic desires and subjectivities which could neither be governed nor contained. I consider how miscegenation fears and fantasies were debated in public discourse, enacted into law, institutionalized through draconian policing and punishment practices, culturally entrenched, yet negotiated and resisted through everyday intimacies. While crime statistics show that most incidences of interracial sex involved White men and women of color, the perceived threat to “White purity” was generally represented through images of White women—volks-mothers and daughters—in the Afrikaner nationalist iconography. White women’s wombs symbolized the future of “Whiteness.” This article offers a critique of the prevailing South African “exceptionalism” paradigm in apartheid studies. Detailed analyses of government commission reports (1939, 1984, 1985) and parliamentary debate records (1949) reveal considerable American influence on South Africa’s “petty apartheid” laws, and especially the Prohibition of Mixed Marriages Act (1949) and Immorality Amendment Act (1950). While these “cornerstone” policies of apartheid developed from local socio-political conflicts and economic tensions, they were always entangled in global racial formations, rooted in trans-oceanic histories of slavery, dispossession, and segregation. This historical anthropological study of race/sex taboo builds on interdisciplinary literatures in colonial history, sociology, postcolonial studies, literary theory, art history, cultural studies, feminist theory, queer studies, and critical race theory.
Effective field theory (EFT) is a computationally powerful theoretical framework, finding application in many areas of physics. The framework, applied to the Standard Model of particle physics, is even more empirically successful than our theoretical understanding would lead us to expect. I argue that this is a problem for our understanding of how the Standard Model relates to some successor theory. The problem manifests as two theoretical anomalies involving relevant parameters: the cosmological constant and the Higgs mass. The persistent failure to fix these anomalies from within suggests that the way forward is to go beyond the EFT framework.
The aim of this study was to compare the levels of reactive oxygen species (ROS) in Bos taurus and Bos indicus in vitro embryos cryopreserved using either slow freezing or vitrification. Embryos were divided into four groups based on subspecies and freezing method: Bos indicus slow freezing (BiSF; n = 8), Bos indicus vitrification (BiVT; n = 10), Bos taurus slow freezing (BtSF; n = 9), and Bos taurus vitrification (BtVT; n = 6). After thawing, the embryos were incubated with CellRox Green and images were obtained using a confocal microscope. The fluorescence intensity of each cell was measured and expressed as arbitrary units of fluorescence (auf) and compared using a multiple regression and unpaired t-test with α = 0.05. Results showed that subspecies and the freezing method significantly affected auf (P < 0.001; R2 = 0.1213). Bos indicus embryos had higher auf than Bos taurus embryos, whether frozen by slow freezing (67.05 ± 23.18 vs 51.30 ± 16.84, P < 0.001) or vitrification (64.44 ± 23.32 vs 47.86 ± 17.53, P < 0.001). Slow freezing induced higher auf than vitrification in both Bos taurus (51.30 ± 16.84 vs 47.86 ± 17.53, P < 0.001) and Bos indicus (67.05 ± 23.18 vs 64.44 ± 23.32, P < 0.014). In conclusion, Bos taurus embryos had lower ROS levels when frozen using vitrification, while Bos indicus embryos had consistent ROS patterns regardless of the freezing method. However, Bos indicus embryos frozen by slow freezing tended to have a higher number of cells with elevated ROS levels.
A growing body of literature is challenging techno-fetishistic perspectives on digital capitalism, as well as claims of the start of a new era characterized by total automation. This article contributes to the ongoing debate on the implications of digital technology for the future of labour by reading Moritz Altenried's The Digital Factory (2022) through the lens of labour history. The use of digital factory and digital Taylorism as integrative tools significantly improves empirical evaluations of different digital labour environments. However, because of their high degree of abstraction, there are a number of limitations when applying these concepts to describe wildly disparate work environments. To illustrate these limits, I use examples from twentieth-century debates on technology and work autonomy, and (1) argue that a labour history perspective warns us against overgeneralizing the effects of technology on labour control and worker autonomy, and (2) broaden the discussion to larger issues of labour control before and during digitalization, incorporating new theoretical questions such as our understanding of classical Taylorism and, by extension, capitalism.
The structure of groups in which every element has prime power order (CP-groups) is extensively studied. We first investigate the properties of group $G$ such that each element of $G\setminus N$ has prime power order. It is proved that $N$ is solvable or every non-solvable chief factor $H/K$ of $G$ satisfying $H\leq N$ is isomorphic to $PSL_2(3^f)$ with $f$ a 2-power. This partially answers the question proposed by Lewis in 2023, asking whether $G\cong M_{10}$? Furthermore, we prove that if each element $x\in G\backslash N$ has prime power order and ${\bf C}_G(x)$ is maximal in $G$, then $N$ is solvable. Relying on this, we give the structure of group $G$ with normal subgroup $N$ such that ${\bf C}_G(x)$ is maximal in $G$ for any element $x\in G\setminus N$. Finally, we investigate the structure of a normal subgroup $N$ when the centralizer ${\bf C}_G(x)$ is maximal in $G$ for any element $x\in N\setminus {\bf Z}(N)$, which is a generalization of results of Zhao, Chen, and Guo in 2020, investigating a special case that $N=G$ for our main result. We also provide a new proof for Zhao, Chen, and Guo's results above.
Abrupt changes in aircraft attitude due to encountering terrain turbulence or wind shear at low altitudes can directly lead to serious accidents. Therefore, a highly responsive and reliable active attitude stabiliser on board is necessary to counteract low-level severe atmospheric disturbances. However, gust environments caused by local terrain and structures are difficult to represent with typical models, such as the Dryden continuous gust model in free space. As a result, an optimal model-based control design cannot be applied. To address this problem, this paper introduces an adaptive mechanism for updating motion equations based on atmospheric conditions using in-flight surface pressure-field sensing. Additionally, a dynamic wind tunnel experiment system, which can be constructed at universities at a low cost, is developed and described in detail. The effectiveness of the proposed scheme is evaluated through wind tunnel experiments and numerical simulations using a large number of gust samples.
Epigenetic mechanisms, such as DNA methylation, histone modifications and non-coding RNA molecules, play a critical role in gene expression and regulation in livestock species, influencing development, reproduction and disease resistance. DNA methylation patterns silence gene expression by blocking transcription factor binding, while histone modifications alter chromatin structure and affect DNA accessibility. Livestock-specific histone modifications contribute to gene expression and genome stability. Non-coding RNAs, including miRNAs, piRNAs, siRNAs, snoRNAs, lncRNAs and circRNAs, regulate gene expression post-transcriptionally. Transgenerational epigenetic inheritance occurs in livestock, with environmental factors impacting epigenetic modifications and phenotypic traits across generations. Epigenetic regulation revealed significant effect on gene expression profiling that can be exploited for various targeted traits like muscle hypertrophy, puberty onset, growth, metabolism, disease resistance and milk production in livestock and poultry breeds. Epigenetic regulation of imprinted genes affects cattle growth and metabolism while epigenetic modifications play a role in disease resistance and mastitis in dairy cattle, as well as milk protein gene regulation during lactation. Nutri-epigenomics research also reveals the influence of maternal nutrition on offspring’s epigenetic regulation of metabolic homeostasis in cattle, sheep, goat and poultry. Integrating cyto-genomics approaches enhances understanding of epigenetic mechanisms in livestock breeding, providing insights into chromosomal structure, rearrangements and their impact on gene regulation and phenotypic traits. This review presents potential research areas to enhance production potential and deepen our understanding of epigenetic changes in livestock, offering opportunities for genetic improvement, reproductive management, disease control and milk production in diverse livestock species.
Sleep apnoea is a known risk factor for cardiometabolic diseases (CMD), but it is unknown whether sleep apnoea or its symptoms contribute to increased CMD through an association with diet quality. This study assessed the association between sleep apnoea symptoms on future diet quality in the Bogalusa Heart Study (BHS). This prospective study included 445 participants who completed a sleep apnoea questionnaire in 2007–2010 and a FFQ in 2013–2016 (mean follow-up: 5·8 years; age 43·5 years; 34 % male; 71 % White/29 % Black persons). Diet quality was measured with the Alternate Healthy Eating Index (AHEI) 2010, the Healthy Eating Index (HEI) 2015 and the alternate Mediterranean diet score. Adjusted mean differences in dietary patterns by sleep apnoea risk, excessive snoring and daytime sleepiness were estimated with multivariable linear regression. Models included multi-level socio-economic factors, lifestyle and health characteristics including BMI, physical activity and depressive symptoms. Those with high sleep apnoea risk, compared with low, had lower diet quality 5·8 years later (percentage difference in AHEI (95 % CI −2·1 % (–3·5 %, −0·7 %)). Daytime sleepiness was associated with lower diet quality. After adjusting for dietary pattern scores from 2001 to 2002, having high sleep apnoea risk and excessive sleepiness were associated with 1·5 % (P < 0·05) and 3·1 % (P < 0·001) lower future AHEI scores, respectively. These findings suggest that individuals with sleep apnea or excessive sleepiness should be monitored for diet quality and targeted for dietary interventions to improve CMD risk.
We consider an internally heated fluid between parallel plates with fixed thermal fluxes. For a large class of heat sources that vary in the direction of gravity, we prove that $\smash { \smash {{\langle {\delta T} \rangle _h}} } \geq \sigma R^{-1/3} - \mu$, where $\smash { \smash {{\langle {\delta T} \rangle _h}} }$ is the average temperature difference between the bottom and top plates, $R$ is a ‘flux’ Rayleigh number and the constants $\sigma,\mu >0$ depend on the geometric properties of the internal heating. This result implies that mean downward conduction (for which $\smash { \smash {{\langle {\delta T} \rangle _h}} }< 0$) is impossible for a range of Rayleigh numbers smaller than a critical value $R_0:=(\sigma /\mu )^{3}$. The bound demonstrates that $R_0$ depends on the heating distribution and can be made arbitrarily large by concentrating the heating near the bottom plate. However, for any given fixed heating profile of the class we consider, the corresponding value of $R_0$ is always finite. This points to a fundamental difference between internally heated convection and its limiting case of Rayleigh–Bénard convection with fixed-flux boundary conditions, for which $\smash {{\langle {\delta T} \rangle _h}}$ is known to be positive for all $R$.
In Amilcar Cabral: The Life of a Reluctant Nationalist, a translation and revision of his earlier Portuguese edition, Antonio Tomas addresses what he sees as a gap between the reality of the armed struggle in Guinea and the ways in which it has been discussed by all previous writers on the subject. He claims to base his critique on newly released archival information and recent publications on Cabral, Portuguese colonialism, and its anti-colonial movements in Africa.
Two-dimensional free-surface flow over localised topography is examined, with the emphasis on the stability of hydraulic-fall solutions. A Gaussian topography profile is assumed with a positive or negative amplitude modelling a bump or a dip, respectively. Steady hydraulic-fall solutions to the full incompressible, irrotational Euler equations are computed, and their linear and nonlinear stability is analysed by computing eigenspectra of the pertinent linearised operator and by solving an initial value problem. The computations are carried out numerically using a specially developed computational framework based on the finite-element method. The Hamiltonian structure of the problem is demonstrated, and stability is determined by computing eigenspectra of the pertinent linearised operator. It is found that a hydraulic-fall flow over a bump is spectrally stable. The corresponding flow over a dip is found to be linearly unstable. In the latter case, time-dependent simulations show that ultimately, the flow settles into a time-periodic motion that corresponds to an invariant solution in an appropriately defined phase space. Physically, the solution consists of a localised large-amplitude wave that pulsates above the dip while simultaneously emitting nonlinear cnoidal waves in the upstream direction and multi-harmonic linear waves in the downstream direction.
Congenital heart disease is the most common birth defect in the United States, with many of the affected infants requiring surgical and/or interventional procedures within their first year of life. The parental impacts of a child’s diagnosis, subsequent hospitalization, and transition to home after discharge are numerous and burdensome, and many experience symptoms of traumatic stress along this trajectory. The purpose of this scoping review was to summarize current available literature related to the traumatic stress experienced by parents of children with heart disease to better understand the prevalence, related factors, and consequences. The Joanna Briggs Institute Scoping Review Framework was implemented to identify 31 relevant peer-reviewed articles published between 2000 and early 2024, including 25 quantitative studies, 3 qualitative studies, and 3 systematic reviews or meta-analyses. This scoping review provides an overview of parent traumatic stress for clinicians caring for children with heart disease at every stage of their clinical course.
MicroRNAs (miRNAs) are endogenous, non-coding RNAs, which are functional in a variety of biological processes through post-transcriptional regulation of gene expression. However, the role of miRNAs in the interaction between Bacillus thuringiensis and insects remains unclear. In this study, small RNA libraries were constructed for B. thuringiensis-infected (Bt) and uninfected (CK) Spodoptera exigua larvae (treated with double-distilled water) using Illumina sequencing. Utilising the miRDeep2 and Randfold, a total of 233 known and 726 novel miRNAs were identified, among which 16 up-regulated and 34 down-regulated differentially expressed (DE) miRNAs were identified compared to the CK. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that potential target genes of DE miRNAs were associated with ABC transporters, fatty acid metabolism and MAPK signalling pathway which are related to the development, reproduction and immunity. Moreover, two miRNA core genes, SeDicer1 and SeAgo1 were identified. The phylogenetic tree showed that lepidopteran Dicer1 clustered into one branch, with SeDicer1 in the position closest to Spodoptera litura Dicer1. A similar phylogenetic relationship was observed in the Ago1 protein. Expression of SeDicer1 increased at 72 h post infection (hpi) with B. thuringiensis; however, expression of SeDicer1 and SeAgo1 decreased at 96 hpi. The RNAi results showed that the knockdown of SeDicer1 directly caused the down-regulation of miRNAs and promoted the mortality of S. exigua infected by B. thuringiensis GS57. In conclusion, our study is crucial to understand the relationship between miRNAs and various biological processes caused by B. thuringiensis infection, and develop an integrated pest management strategy for S. exigua via miRNAs.
Optimal diet and nutrition is vital for military readiness, performance and recovery. Previous research on military diets has primarily focused on the nutritional composition of field/combat rations and dietary intake during deployment. There is accumulating research exploring the usual free-living dietary intake and nutritional status of defence members in garrison (i.e. military bases on which personnel are stationed). However, no comprehensive review has been conducted to assess the overall dietary quality of defence members internationally. Therefore, this review assessed the diets of military populations against national nutritional guidelines and Military Dietary Reference Intakes (MDRI). A systematic literature review of original research was conducted. CINAHL, Medline (EBSCO), Scopus (Elsevier), PubMed and AMED databases were searched up to the 20/02/2023. A total of thirty-six studies met the inclusion criteria. The overall quality of included studies was high, with a low risk of bias. The diet quality scores indicate poor to fair diet quality among defence members. Defence members display low intakes of fruits, vegetables, wholegrains, seafood, plant protein and nuts and high intakes of added sugars, trans fat and processed meat. Results also indicated suboptimal intake of fibre, essential fatty acids, vitamin A, vitamin E, folate, Mg, Zn and iodine. This may lead to reduced performance, increased risk of chronic diseases and mental health disorders. More research is needed to assess the long-term consequences of poor diet quality in defence members. These results require the attention of policymakers to ensure that military education and food environment is supportive of healthy eating.
Instructed second language acquisition (ISLA) is one of the fastest growing areas of applied linguistics. With this tremendous potential comes great responsibility for robust, ethical, and transparent research methods that are responsive to and tailored for the ISLA domain. This article highlights unique characteristics of ISLA research, provides a current landscape of methodological trends within ISLA, and makes specific recommendations for research methods in future ISLA studies. I begin by briefly operationalizing ISLA and articulating some of the main research questions and overarching goals within ISLA, as well as the nature and ultimate aims of ISLA research. Next, the most unique methodological challenges for ISLA research are reviewed, including the use of intact classes and heterogeneous small participant pools, cross-sectional studies, using one’s own students for research, and individual differences. This is followed by a discussion of several current trends in ISLA research methods, including examining the process of learning/development, conducting practice-based research, expanding our conceptualization of instructional contexts, replication studies, especially with bi/multilingual learners in diverse contexts, refining our methods with an eye for ethics and justice, equity, diversity, and inclusion, and conducting open, transparent research that has potential for real-world impact and which dialogues with multiple stakeholders at all stages. I conclude by highlighting that, as ISLA continues as an independent research domain, the development and implementation of strong research methods tailored for ISLA is critical for research integrity and to make the greatest strides in understanding language acquisition processes and effective pedagogical interventions in diverse instructional contexts.
This study examines the effects of the chemical composition of the clay fraction of various soil horizons on radiation shielding parameters. X-ray fluorescence (XRF) analysis did not reveal significant differences in the concentration of the most abundant oxides (Al2O3, SiO2, Fe2O3) among the various horizons. Consequently, the mass attenuation coefficient did not vary among the horizons in terms of the photon energies studied (15 keV–10 MeV). The mean free path (MFP), half-value layer (HVL) and tenth-value layer (TVL) did not differ for energies up to 100 keV. However, at higher energies, these parameters were mainly influenced by the differences in the densities of the soil horizons. The effective atomic number did not differ across the horizons for the various photon energies, nor did the mass attenuation coefficient. It is shown that slight differences in the chemical composition of the clay fraction of soil horizons do not affect radiation shielding parameters (MFL, HVL, TVL) for low photon energies (<500 keV). Density is more important for radiation shielding than the chemical composition of the various horizons of the same soil type for higher energies (>100 keV); hence, compacting the clay fraction might be more efficient for radiation shielding purposes at higher energies.
This study reports on the relationship between timing of initial hepatitis B virus (HBV) vaccine series and HBV antibody immunity in healthcare personnel (HCP) screened prior to employment. HCPs vaccinated as neonates were significantly more likely to have negative or indeterminate antibodies. An alternative screening approach is considered.
Attrition is monotonic when agents leaving multi-period studies do not return. Under a general missing at random (MAR) assumption, we study efficiency in estimation of parameters defined by moment restrictions on the distributions of the counterfactuals that were unrealized due to monotonic attrition. We discuss novel issues related to overidentification, usability of sample units, and the information content of various MAR assumptions for estimation of such parameters. We propose a standard doubly robust estimator for these parameters by equating to zero the sample analog of their respective efficient influence functions. Our proposed estimator performs well and vastly outperforms other estimators in our simulation experiment and empirical illustration.