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It is important to understand how ballistic materials respond to impact from projectiles such that informed decisions can be made in the design process of protective armour systems. Ballistic testing is a standards-based process where materials are tested to determine whether they meet protection, safety and performance criteria. For the V50 ballistic test, projectiles are fired at different velocities to determine a key design parameter known as the ballistic limit velocity (BLV), the velocity above which projectiles perforate the target. These tests, however, are destructive by nature and as such there can be considerable associated costs, especially when studying complex armour materials and systems. This study proposes a unique solution to the problem using a recent class of machine learning system known as the Generative Adversarial Network (GAN). The GAN can be used to generate new ballistic samples as opposed to performing additional destructive experiments. A GAN network architecture is tested and trained on three different ballistic data sets, and their performance is compared. The trained networks were able to successfully produce ballistic curves with an overall RMSE of between 10 and 20 % and predicted the V50 BLV in each case with an error of less than 5 %. The results demonstrate that it is possible to train generative networks on a limited number of ballistic samples and use the trained network to generate many new samples representative of the data that it was trained on. The paper spotlights the benefits that generative networks can bring to ballistic applications and provides an alternative to expensive testing during the early stages of the design process.

Whole genome sequencing (WGS), despite its advantages, is yet to replace alternative methods for genotyping single nucleotide variants (SNVs). Structural variants (SVs) have larger effects on traits than SNVs, but are more challenging to accurately genotype. Using low-coverage WGS with genotype imputation offers a cost-effective strategy to achieve genome-wide variant coverage, but is yet to be tested for SVs. Here, we investigate combined SNV and SV imputation with low-coverage WGS data in Atlantic salmon (Salmo salar). As the reference panel, we used genotypes for high-confidence SVs and SNVs for n=445 wild individuals sampled from diverse populations. We also generated 15x WGS data (n=20 samples) for a commercial population out-with the reference panel, and called SVs and SNVs with gold-standard approaches. An imputation method (GLIMPSE) was tested at WGS depths of 1x, 2x, 3x and 4x for samples within and out-with the reference panel. SNVs were imputed with high accuracy and recall across all WGS depths, including for samples out-with the reference panel. For SVs, we compared imputation based purely on linkage disequilibrium (LD) with SNVs, to that supplemented with SV genotype likelihoods (GLs) from low-coverage WGS. Including SV GLs increased imputation accuracy, but as a trade-off with recall, requiring 3-4x coverage for best performance. Combining strategies allowed us to capture 84% of the reference panel deletions with 87% accuracy at 1x WGS. This study highlights the promise of reference panel imputation using low-coverage WGS, including novel opportunities to enhance the resolution of genome-wide association studies by capturing SVs.

A commercial breeding programme in Atlantic salmon utilises a four-year generation interval with four parallel breeding populations. In this study, we develop a computer simulation of a salmon breeding programme and explore the impact of gene flow between the parallel year groups on the accuracy of genomic prediction within and between breeding lines. We simulated four parallel lines for 10 discrete generations with random selection and different mixing rates between parallel year groups. The genetic distance between fish (as a measure of diversity) and the accuracy of estimated genomic breeding values were used as criteria of comparison. With no mixing the genetic distance increased between populations, the genetic variation within populations decreased and there was no increase in accuracy when combining data across populations. Even a low percentage of mixing decreased the genetic distance between populations and increased the genetic variation within populations. The higher the percentage of mixing the faster the lines became more similar. The accuracy of prediction climbed as the percentage of mixing increased. The increase in accuracy from the combined evaluation approach compared to the within evaluation approach was greater with an increased percentage of mixing. In conclusion, if there is no gene flow between populations the lines drift apart and there is no value in combining information across populations for genomic breeding value prediction. Only a low amount of mixing between lines brings the lines closer together and facilitates the use of information across lines to improve breeding value prediction. Optimising gene flow between lines should be an integral part of salmon breeding programme design.

Commonly we see large within-age-group variations in physique, including body mass, stature, and percentages of predicted adult height, which suggests that age-specified training loads are flawed. Aims were to investigate how maturation impacts training load and neuromuscular response within academy soccer and, to provide recommendations for practitioners. Fifty-five male soccer players (age 14.5 ± 1.2 years; stature 172 ± 10 cm; body mass 59.8 ± 10 kg; 94.1 ± 1.8 % predicted adult height) reported differential ratings of perceived exertion (AU) across a season. Neuromuscular performance (countermovement jump, reactive strength index, absolute and relative leg stiffness) was measured using at three timepoints across the season. Perceived exertion and neuromuscular performance were examined using linear mixed modelling, supplemented with non-clinical magnitude-based decisions. Analysis indicates every 5% increase in maturity status results in players perceiving overall session intensity 6.9 AU lower and 13.9 AU lower for a 10% maturity shift. Both 5% and 10% changes in maturity most likely resulted in higher countermovement jump, with likely to very likely differences observed for RSI and ABS. Maturity substantially influences neuromuscular performance over the season. Therefore, maturity-specific load prescription may prevent significant within age-group differences in accumulated load, possibly reducing injury risk and/or burnout.

Genetic resistance to infectious pancreatic necrosis virus (IPNV) in Atlantic salmon is a rare example of a trait where a single locus (QTL) explains almost all of the genetic variation. Genetic marker tests based on this QTL on salmon chromosome 26 have been widely applied in selective breeding to markedly reduce the incidence of the disease. In the current study, whole genome sequencing and functional annotation approaches were applied to characterise genes and variants in the QTL region. This was complemented by an analysis of differential expression between salmon fry of homozygous resistant and homozygous susceptible genotypes challenged with IPNV. These analyses pointed to the NEDD-8 activating enzyme 1 (nae1) gene as a putative functional candidate underlying the QTL effect. The role of nae1 in IPN resistance was further assessed via CRISPR-Cas9 knockout of the nae1 gene and chemical inhibition of the nae1 protein activity in Atlantic salmon cell lines, both of which resulted in highly significant reduction in productive IPNV replication. In contrast, CRISPR-Cas9 knockout of a candidate gene previously purported to be a cellular receptor for the virus (cdh1) did not have a major impact on productive IPNV replication. These results suggest that nae1 is the causative gene underlying the major QTL affecting resistance to IPNV in salmon, provide further evidence for the critical role of neddylation in host-pathogen interactions, and highlight the value in combining high-throughput genomics approaches with targeted genome editing to understand the genetic basis of disease resistance., Highlights • Whole genome sequencing and functional annotation were used to characterise the major IPNV resistance QTL in Atlantic salmon. • Gene expression analyses pointed to NEDD-8 activating enzyme 1 (nae1) as a putative functional candidate underlying the QTL. • CRISPR-Cas9 knockout and chemical inhibition of nae1 in cell lines resulted in significant reduction in IPNV replication. • CRISPR-Cas9 knockout of a previously suggested candidate gene (cdh1) did not have an impact on productive IPNV replication. • These results suggest that nae1 is the causative gene underlying the major QTL affecting resistance to IPNV in salmon.

This article discusses three aspects of Arabic studies at Oxford – the actual teaching of the language, the use of the Bodleian library, and the publications of the university press. At a time when fewer and fewer prospective Arabists endeavoured to learn the language at a university, the teaching of Arabic at Oxford was directed at a decreasing number of students and made no progress with respect to the achievements of the seventeenth century. Although a number of the Oxford professors of Oriental languages were esteemed members of the Republic of Letters, the greatest contributions to the teaching was made by scholars such as the Hungarian Joannes Uri who was employed by the Bodleian and was never part of the university staff. With one of the finest collections of Arabic manuscripts in the West, the Bodleian offered scholars immense possibilities, drawing Arabists from all over Protestant Europe and leading to major publications of Arabic texts and works on Islam and the Arab world. Many of these publications appeared thanks to the university press. Clearly in decline in the first half of the eighteenth century, it experienced a revival which allowed it to retrieve much of its former importance in the second.

This chapter analyses William Guise’s use of Arabic in his notes to his partial translation of Zera´im. His main sources were the monolingual Arabic dictionaries—al-Jawharī’s Ṣiḥāḥ, Fīrūzābādī’s Qāmūs, the Asās al-balāgha by al-Zamakhsharī, al-Fayyūmī’s Miṣbāḥ al-munīr, and al-Muṭarrizī’s Mughrib—and the medical and botanical ‘dictionaries’ of Ibn Jazla, Ibn al-Bayṭar, and Serapion the Younger. From these sources he derived quotations from other, far earlier, writers. His principal objective was to confirm, or, more often, to contradict, interpretations by other commentators, and to give the Arabic equivalents of certain Hebrew words. His ability to translate some of the more difficult texts proves that, despite the arrogance for which he was so frequently reproached, Guise was one of the most accomplished Arabists of his generation

Manuscripts, Politics and Oriental Studies: Life and Collections of Johann Gottfried Wetzstein (1815– 1905) in Context. Edited by Boris Liebrenz and Christoph Rauch. Islamic Manuscripts and Books, vol. 19. Leiden: Brill, 2019. Pp. xxiii + 437, illus. $130, €108.

Un principe nel deserto: Leone Caetani nel Sinai e nel Sahara. I diari, le lettere, le fotografie (1888– 1890). By Valentina Sagaria Rossi. Accademia nazionale dei Lincei, Fondazione Leone Caeta- ni, vol. 28. Rome: Bardi ediZioni, 2018. Pp. 561, illus. €68.

We offer a new approach to large $N$ limits using the Batalin-Vilkovisky formalism, both commutative and noncommutative, and we exhibit how the Loday-Quillen-Tsygan Theorem admits BV quantizations in that setting. Matrix integrals offer a key example: we demonstrate how this formalism leads to a recurrence relation that in principle allows us to compute all multi-point correlation functions. We also explain how the Harer-Zagier relations may be expressed in terms of this noncommutative geometry derived from the BV formalism. As another application, we consider the problem of quantization in the large $N$ limit and demonstrate how the Loday-Quillen-Tsygan Theorem leads us to a solution in terms of noncommutative geometry. These constructions are relevant to open topological field theories and string field theory, providing a mechanism that relates moduli of categories of branes to moduli of brane gauge theories., Comment: 45 pages