Cambridge University Research Outputs

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The mission of the University of Cambridge is to contribute to society through the pursuit of education, learning, and research at the highest international levels of excellence. This collection contains the latest research outputs of the University's academic staff and students.

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Hesiod's holistic authority in Neoplatonist exegesis
(Cambridge University Press, ) Wood, Connor
The Neoplatonist scholarch Proclus defined three categories of poetry. Traditionally it has been thought that he considered only Homer to have excelled in all three, while other poets could fulfil one or at most two functions. It will be shown that Proclus also conceived of Hesiod as excelling in all three types and thereby assimilated Hesiodic authority to Homeric. He also considered Orpheus but assigned his poetry to just one category, not all three. In doing this he increased his own authority as a teacher-hierophant, contributing to the dialogue between pagan Platonism and Christianity over the inspiration of texts.
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Prevalence of neoplasia and concurrent diseases in dogs and cats with hypercobalaminemia: a retrospective case control study
(Wiley, ) Henry, Perrine; Williams, Timothy; Williams, Timothy [0000-0002-9775-8285]
Background: Hypercobalaminemia is infrequently reported in companion animals and considered of low clinical significance. Recent studies have described its association with inflammatory, immune mediated, endocrine and neoplastic conditions in dogs and cats. Objectives: We aimed to investigate the association between hypercobalaminemia and neoplasia in companion animals, and to identify other concurrent diseases or clinicopathological changes. Methods: Retrospective, case control study. Medical records of patients with measured serum cobalamin concentration (2015-2020) and no history of prior supplementation were reviewed. Hypocobalaminemic animals were excluded. Variables were compared between groups (hypercobalaminemic vs normocobalaminemic) using non-parametric statistics. Data are presented as median (range). Results: Thirty-five dogs and 8 cats were hypercobalaminemic. At baseline, neoplasia was confirmed in 4/35 hypercobalaminemic dogs vs. 11/70 control dogs (p=0.77), and 0/8 hypercobalaminemic cats vs. 3/16 control cats (p=0.53). Cases without neoplasia at baseline were followed for 409 (13-1854) days (dogs, n=78) and 395 (28-1670) days (cats, n=21). During follow up, neoplasia was diagnosed in 4/27 hypercobalaminemic dogs vs. 3/51 control dogs (p=0.23), and 1/8 hypercobalaminemic cats vs. 0/13 control cats (p=0.38). Pancreatitis was more frequent in hypercobalaminemic dogs (p=0.006). Hypercobalaminemic dogs had higher serum total protein (p=0.014), globulin (p=0.001) and CRP (p=0.032) concentrations, and lower serum sodium (p=0.012) and chloride (p=0.033) concentrations than controls. Hypercobalaminemic cats had higher serum total protein concentrations than controls (p=0.008). Conclusion: Our results suggest that hypercobalaminemia is not associated with presence or development of neoplasia in dogs and cats, but may be associated with systemic inflammatory conditions, including pancreatitis, in dogs.
Open Access
Existential insecurity and deference to authority: the pandemic as a natural experiment
(Frontiers Media SA, ) Foa, Roberto Stefan; Welzel, Christian; Foa, Roberto Stefan [0000-0001-8867-7566]
IntroductionThe global coronavirus pandemic offers a quasi-experimental setting for understanding the impact of sudden exposure to heightened existential risk upon both individual and societal values.MethodsWe examined the effect of the pandemic on political attitudes by comparing data from eight countries surveyed before and after the worldwide spread of COVID-19 in March 2020 with continuous weekly polling tracker data from the United Kingdom from 2019 to 2021. Multilevel models were used to explore the drivers of change, and the results indicated that reported emotions of fear and stress were positively associated with institutional approval during periods of greater pathogen risk.ResultsOur findings revealed that support for political and technocratic authority, as well as satisfaction with political institutions, rose significantly above long-term historical baselines during the pandemic.DiscussionThe results support the hypothesis that exposure to existential risk results in greater support for authority and that individual feelings of insecurity may be linked to less critical citizen orientations.
Open Access
The Coronavirus Pandemic and Religious Freedom: Judicial Decisions in the United States and United Kingdom
(Informa UK Limited, 2021-10-02) Baldwin, Guy; Baldwin, Guy [0000-0003-2765-4437]
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Same-Sex Marriage in Japan and the Role of Courts in a Dominant Party System
(Edward Elgar Publishing, ) Baldwin, Guy
Japan is increasingly isolated among advanced economies in not having made provision for same-sex marriage or same-sex civil unions at the national level. The main political obstacle to legal recognition of same-sex couples is the Liberal Democratic Party (LDP), Japan’s dominant party, which has ruled the country with only two interruptions since 1955; many other parties support legalizing same-sex marriage, while the LDP does not. The literature suggests that the LDP secured its dominant position due to opposition fragmentation and ineffectiveness, and its own clientelist practices. Against this backdrop, cases are progressing through the Japanese judicial system seeking a finding that same-sex marriage is required under the 1947 Constitution. So far, the results of these cases have been mixed, with one case finding the current marriage law unconstitutional and two finding it constitutional. This article contends that Japanese courts should find in favour of these claims and hold that same-sex marriage is constitutionally required. That is so not merely because it is the better position under existing legal doctrine relating to equality and non-discrimination under Article 14(1) of the Constitution, but also because the dominant party status of the LDP means that there is less reason in constitutional theory for courts to show deference to the legislature. In a dominant party system, there is less reason to expect that the government will pay sufficient heed to rights, while ‘counter-majoritarian’ difficulties with judicial review are less credible given the more ambiguous nature of the democratic mandate of the legislature in a dominant party system. This undercuts a significant justification given for judicial deference.
Open Access
Cardiometabolic Health: Key in Reducing Adverse COVID-19 Outcomes.
(Ubiquity Press, Ltd., 2020-08-19) Chowdhury, Rajiv; van Daalen, Kim R; Franco, Oscar H
Whilst current public health measures focused on good hygiene practices and limiting person-to-person transmission contribute effectively in managing the COVID-19 pandemic, they will not prevent all individuals from becoming infected. Thus, it is of importance to explore what individuals could do to mitigate adverse outcomes. The value of beneficial health behaviours and a healthy lifestyle to improve immune functioning and lower adverse consequences of COVID-19 are increasingly being emphasized. Here we discuss seven key health behaviours and corresponding recommendations that may assist in reducing unfavourable COVID-19 outcomes.
Open Access
Nutritional Intake after Liver Transplant: Systematic Review and Meta-Analysis
(MDPI AG, ) Spillman, Lynsey N; Madden, Angela M; Richardson, Holly; Imamura, Fumiaki; Jones, Danielle; Nash, Marilyn; Lim, Hong Kai; Hellawell, Holly N; Rennie, Kirsten L; Oude Griep, Linda M; Allison, Michael; Griffin, Simon J; Spillman, Lynsey N [0000-0003-1409-0273]; Madden, Angela M [0000-0001-6353-6492]; Jones, Danielle [0000-0003-0372-5579]; Lim, Hong Kai [0000-0002-7266-7790]; Oude Griep, Linda M [0000-0001-7697-7473]; Allison, Michael [0000-0003-3677-3294]
Cardiovascular disease and its concurrent risk factors are prevalent after liver transplant (LT). Most of these risk factors are modifiable by diet. We aimed to synthesise the literature reporting the nutritional intake of liver transplant recipients (LTR) and the potential determinants of intake. We performed a systematic review and meta-analyses of studies published up until July 2021 reporting the nutritional intake of LTR. The pooled daily mean intakes were recorded as 1998 (95% CI 1889, 2108) kcal, 17 (17, 18)% energy from protein, 49 (48, 51)% energy from carbohydrates, 34 (33, 35)% energy from total fat, 10 (7, 13)% energy from saturated fat, and 20 (18, 21) g of fibre. The average fruit and vegetable intake ranged from 105 to 418 g/day. The length of time post-LT and the age and sex of the cohorts, as well as the continent and year of publication of each study, were sources of heterogeneity. Nine studies investigated the potential determinants of intake, time post-LT, gender and immunosuppression medication, with inconclusive results. Energy and protein requirements were not met in the first month post-transplant. After this point, energy intake was significantly higher and remained stable over time, with a high fat intake and low intake of fibre, fruits and vegetables. This suggests that LTR consume a high-energy, low-quality diet in the long term and do not adhere to the dietary guidelines for cardiovascular disease prevention.
Open Access
High-throughput phenotyping reveals expansive genetic and structural underpinnings of immune variation.
(Springer Science and Business Media LLC, 2020-01) Abeler-Dörner, Lucie; Laing, Adam G; Lorenc, Anna; Ushakov, Dmitry S; Clare, Simon; Speak, Anneliese O; Duque-Correa, Maria A; White, Jacqueline K; Ramirez-Solis, Ramiro; Saran, Namita; Bull, Katherine R; Morón, Belén; Iwasaki, Jua; Barton, Philippa R; Caetano, Susana; Hng, Keng I; Cambridge, Emma; Forman, Simon; Crockford, Tanya L; Griffiths, Mark; Kane, Leanne; Harcourt, Katherine; Brandt, Cordelia; Notley, George; Babalola, Kolawole O; Warren, Jonathan; Mason, Jeremy C; Meeniga, Amrutha; Karp, Natasha A; Melvin, David; Cawthorne, Eleanor; Weinrick, Brian; Rahim, Albina; Drissler, Sibyl; Meskas, Justin; Yue, Alice; Lux, Markus; Song-Zhao, George X; Chan, Anna; Ballesteros Reviriego, Carmen; Abeler, Johannes; Wilson, Heather; Przemska-Kosicka, Agnieszka; Edmans, Matthew; Strevens, Natasha; Pasztorek, Markus; Meehan, Terrence F; Powrie, Fiona; Brinkman, Ryan; Dougan, Gordon; Jacobs, William; Lloyd, Clare M; Cornall, Richard J; Maloy, Kevin J; Grencis, Richard K; Griffiths, Gillian M; Adams, David J; Hayday, Adrian C; Lorenc, Anna [0000-0002-1406-7607]; Speak, Anneliese O [0000-0003-4890-4685]; Morón, Belén [0000-0003-4815-7536]; Weinrick, Brian [0000-0003-0880-4487]; Powrie, Fiona [0000-0003-3312-5929]; Lloyd, Clare M [0000-0001-8977-6726]; Cornall, Richard J [0000-0002-6213-3269]; Grencis, Richard K [0000-0002-7592-0085]; Griffiths, Gillian M [0000-0003-0434-5842]; Adams, David J [0000-0001-9490-0306]; Hayday, Adrian C [0000-0002-9495-5793]
By developing a high-density murine immunophenotyping platform compatible with high-throughput genetic screening, we have established profound contributions of genetics and structure to immune variation (http://www.immunophenotype.org). Specifically, high-throughput phenotyping of 530 unique mouse gene knockouts identified 140 monogenic 'hits', of which most had no previous immunologic association. Furthermore, hits were collectively enriched in genes for which humans show poor tolerance to loss of function. The immunophenotyping platform also exposed dense correlation networks linking immune parameters with each other and with specific physiologic traits. Such linkages limit freedom of movement for individual immune parameters, thereby imposing genetically regulated 'immunologic structures', the integrity of which was associated with immunocompetence. Hence, we provide an expanded genetic resource and structural perspective for understanding and monitoring immune variation in health and disease.
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Downregulation of Extraembryonic Tension Controls Body Axis Formation in Avian Embryos
(Nature Portfolio, ) Xiong, Fengzhu; Xiong, Fengzhu [0000-0002-6153-0254]
Embryonic tissues undergoing shape change draw mechanical input from extraembryonic substrates. In avian eggs, the early blastoderm disk is under the tension of the vitelline membrane (VM). Here we report that the chicken VM characteristically downregulates tension and stiffness to facilitate stage-specific embryo morphogenesis. Experimental relaxation of the VM early in development impairs blastoderm expansion, while maintaining VM tension in later stages resists the convergence of the posterior body causing stalled elongation, failure of neural tube closure, and axis rupture. Biochemical and structural analysis shows that VM weakening is associated with the reduction of outer-layer glycoprotein fibers, which is caused by an increasing albumen pH due to CO2 release from the egg. Our results identify a previously unrecognized potential cause of body axis defects through mis-regulation of extraembryonic tissue tension.
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Genomics of cold adaptations in the Antarctic notothenioid fish radiation
(Nature Portfolio, ) Durbin, Richard; Miska, Eric; McCarthy, Shane; Durbin, Richard [0000-0002-9130-1006]
Numerous novel adaptations characterise the radiation of notothenioids, the dominant fish group in the freezing seas of the Southern Ocean. To improve understanding of the evolution of this iconic fish group, here we generate and analyse new genome assemblies for 24 species covering all major subgroups of the radiation, including five long-read assemblies. We present a new estimate for the onset of the radiation at 10.7 million years ago, based on a time-calibrated phylogeny derived from genome-wide sequence data. We identify a two-fold variation in genome size, driven by expansion of multiple transposable element families, and use the long-read data to reconstruct two evolutionarily important, highly repetitive gene family loci. First, we present the most complete reconstruction to date of the antifreeze glycoprotein gene family, whose emergence enabled survival in sub-zero temperatures, showing the expansion of the antifreeze gene locus from the ancestral to the derived state. Second, we trace the loss of haemoglobin genes in icefishes, the only vertebrates lacking functional haemoglobins, through complete reconstruction of the two haemoglobin gene clusters across notothenioid families. Both the haemoglobin and antifreeze genomic loci are characterised by multiple transposon expansions that may have driven the evolutionary history of these genes.
Open Access
Progressive cities: Urban–rural polarisation of social values and economic development around the world
(SAGE Publications, 2023) Luca, D; Terrero-Davila, J; Stein, J; Lee, N; Stein, J [0000-0003-2902-042X]
In contrast to the conservative values of rural populations, cities are often seen as bulwarks of more tolerant, liberal and progressive values. This urban–rural divide in values has become one of the major fault lines in Western democracies, underpinning major political events of the last decade, not least the election of Donald Trump. Yet, beyond a small number of countries, there is little evidence that cities really are more liberal than rural areas. Evolutionary modernisation theory suggests that socio-economic development may lead to the spread of progressive, self-expression values but provides little guidance on the role of cities in this process. Has an urban–rural split in values developed across the world? And does this gap depend on the economic development of a country? We answer these questions using a large cross-sectional dataset covering 66 countries. Despite the inherent challenges in identifying and operationalising a globally-consistent definition of what is ‘urban’, we show that there are marked and significant urban–rural differences in progressive values, defined as tolerant attitudes to immigration, gender rights and family life. These differences exist even when controlling for observable compositional effects, suggesting that cities do play a role in the spread of progressive values. Yet, these results only apply at higher levels of economic development suggesting that, for cities to leave behind rural areas in terms of liberal values, the satisfying of certain material needs is a prerequisite.
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Analysis of nonlinear vibration transmission through a vehicle suspension damper at low audio frequencies
(Elsevier BV, 2023-05) de Brett, M; Butlin, T; Nielsen, OM; de Brett, M [0000-0003-3715-7143]; Butlin, T [0000-0002-7814-8107]
Active control is an attractive solution to the problem of structure-borne interior road noise in cars. However, nonlinear suspension dynamics could limit the cancellation that can be achieved with a linear feedforward road noise control system. The hydraulic dampers in a vehicle suspension have previously been found to be a source of nonlinear vibration transmission at low audio frequencies. This paper presents experimental measurements and modelling of the front and rear suspension dampers in a test vehicle aimed at understanding the physical processes causing their nonlinear dynamics. Experiments are shown that highlight the different nonlinear effects present in the dampers, including friction and the mechanics of the piston valves. A suitable model was then selected from the literature, fitted to the measurements and validated. Analysis of the models revealed that, in the front damper, both friction and the valve mechanics contribute significantly to the damper's nonlinear dynamics between 50–300 Hz. Friction in the rear damper is much less significant, meaning that its nonlinear dynamics are almost entirely caused by the piston valves. Although the front damper's friction behaviour proved challenging to model, the effect of the piston valves was captured very accurately in both damper models.
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An atlas of rabbit development as a model for single-cell comparative genomics
(Nature Research, ) Gottgens, Berthold; Gottgens, Berthold [0000-0001-6302-5705]
Traditionally, the mouse has been the favored vertebrate model for biomedical research, due to its experimental and genetic tractability. However, non-rodent embryological studies highlight that many aspects of early mouse development, such as its egg-cylinder gastrulation and method of implantation, diverge from other mammals, thus complicating inferences about human development. Like the human embryo, rabbits develop as a flat-bilaminar disc. In this study, we constructed a morphological and molecular atlas of rabbit development. We report transcriptional and chromatin accessibility profiles for over 180,000 single cells and high resolution histology sections from embryos spanning gastrulation, implantation, amniogenesis, and early organogenesis. Using a neighborhood comparison pipeline, we compare the transcriptional landscape of rabbit and mouse at the scale of the entire organism. We characterize the gene regulatory programs underlying trophoblast differentiation and identify signaling interactions involving the yolk sac mesothelium during hematopoiesis. We demonstrate how the combination of both rabbit and mouse atlases can be leveraged to extract new biological insights from sparse macaque and human data. The datasets and computational pipelines reported here set a framework for a broader cross-species approach to decipher early mammalian development, and are readily adaptable to deploy single cell comparative genomics more broadly across biomedical research.
Open Access
Topological invariance in whiteness optimisation
(Nature Portfolio, 2021-07-02) Haataja, Johannes S; Jacucci, Gianni; Schertel, Lukas; Vignolini, Silvia; Haataja, Johannes [0000-0002-4523-4199]; Jacucci, Gianni [0000-0002-9156-0876]; Schertel, Lukas [0000-0003-0977-0389]; Vignolini, Silvia [0000-0003-0664-1418]
Increasing the light scattering efficiency of nanostructured materials is becoming an active field of research both in fundamental science and commercial applications. In this context, the challenge is to use inexpensive organic materials that come with a lower refractive index than currently used mineral nanoparticles, which are under increased scrutiny for their toxicity. Although several recent investigations have reported different disordered systems to optimise light scattering by morphological design, no systematic studies comparing and explaining how different topological features contribute to optical properties have been reported yet. Using in silico synthesis and numerical simulations, we demonstrate that the reflectance is primarily determined by second order statistics. While remaining differences are explained by surface area and integrated mean curvature, an equal reflectance can be obtained by further tuning the structural anisotropy. Our results suggest a topological invariance for light scattering, demonstrating that any disordered system can be optimised for whiteness.
Open Access
WHO simulations for youth engagement in global governance in a post-COVID world: Opportunities and challenges of moving conferences online.
(International Global Health Society, 2021-05-22) Li, Jiaqi; John, Abinayah; Tasos, Emmanouil; Koerling, Anna-Lucia; Rendina, Charlotte; Elshaer, Ahmed; Brunet, Constance; Magdy, Ahmed; Lyszkowski, Alexander; van Daalen, Kim
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Judicial review in the tax field: not a spent force
(Routledge, ) de Cogan, Dominic; de Cogan, Dominic [0000-0003-1037-4770]
Concern about the width of tax authority powers and their effects on taxpayers is hardly confined to the UK or to modern times. Indeed, the relationship between the public imperatives of taxation (including revenue-raising, regulation and redistribution) and the private interests of taxpayers has long been deeply contentious not only in practical tax administration but also in constitutional and philosophical debates about taxation. Nevertheless, there is something distinctively worrying about the recent UK practice in which new statutory powers are conferred on HM Revenue & Customs (HMRC) in each annual Finance Bill, possibly as a way of demonstrating the government’s seriousness of purpose in tackling tax avoidance rather than because the powers are genuinely needed, and certainly without a consistent vision of what powers ought and ought not to be possessed by a tax authority. A number of investigations have been carried out by Parliamentary committees, research institutions and HMRC itself with a view to rationalising or at least reorganising HMRC’s powers, but these are typically overtaken by the conferral of even more powers. They have, in any case, not fully succeeded in fostering a culture of greater deliberation about how best to equip HMRC in carrying out its statutory functions of raising and managing taxes.
Open Access
Equivalent linearisation in a hybrid FE-SEA approach for nonlinear vibro-acoustic modelling
(Elsevier BV, 2022) Andrade, L; Langley, RS; Butlin, T; Andrade, L [0000-0003-0679-9354]; Langley, RS [0000-0001-9978-9790]; Butlin, T [0000-0002-7814-8107]
Hybrid techniques, such as a Finite Element-Statistical Energy Analysis (FE-SEA), have been widely employed to model vibro-acoustic systems in order to estimate the ensemble averaged response due to external inputs, assuming that the governing equations of motion of the comprising structures and connections are linear. However, nonlinear behaviour can be found in the interfaces between the point where the input is applied and the system itself, resulting in the force being transmitted through a nonlinear path, that might affect the structural or acoustic response of the system depending on the amplitude of the input. With the aim of improving the estimation of the mean squared response of the system subjected to random inputs through a nonlinear interface, an equivalent linearisation approach has been adopted to linearise the equations of an existing FE-SEA method that supports prescribed displacements as inputs rather than forces. Results from numerical simulations of a nonlinear single degree of freedom system demonstrate the ability of the equivalent linearisation approach to estimate the mean square response with a minimum error, even for systems with strong nonlinearities. The method here developed has been validated against experimental data collected from a vibro-acoustic system excited through a nonlinear massless and undamped spring.
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Changes in Perceptions of Teaching Quality in Secondary Schools in Rwanda During the COVID-19 Global Pandemic and the Subsequent Closing and Reopening of Schools
(Elsevier, ) Carter, Emma; Leonard, Phil; Onwuegbuzie, anthony; Rose, Pauline; Sabates Aysa, Ricardo; Sabates Aysa, Ricardo [0000-0002-1433-5667]
The stability of measures of teaching quality is essential for making generalizations of results stemming from these measures to other teaching situations. However, no research has examined the effects of unexpected situational factors on the stability of these measures. Therefore, the purpose of this two-phase quantitative research study was to examine the following aspects among secondary school teachers in Rwanda, using a score-validated, multiple-dimension measure: (a) perceptions of teaching quality (PTQ) prior to the onset of the COVID-19 context (Phase 1; descriptive and correlational design); and (b) the extent to which COVID-19 and the subsequent closing and reopening of secondary schools affected PTQ among STEM teachers in Rwanda, and the associations between these changes in PTQ and selected socio-demographic/locational variables (Phase 2; descriptive and correlational research design). Phase 1 findings revealed that two measures of cultural values (i.e., Attitudes Towards Cultural Values Scale, Inculcating Cultural Values Scale, respectively) generated the most positive attitudes, whereas the Satisfaction with Resources and Material Subscale yielded the least positive attitudes. Phase 2 findings revealed that for four of the nine PTQ scales/subscales, the COVID-19 context negatively affected PTQ. These findings provide compelling evidence of the importance of monitoring PTQ, especially during times of crises. Moreover, these findings have implications for Rwandan educational policymakers, Rwandan administrators, teacher training administrators, and, above all, the teachers themselves, as they all seek to maximize teaching quality in Rwandan secondary schools.
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Human soluble CD39 displays substrate inhibition in a substrate-specific manner
(Nature Portfolio, ) Harper, Matthew; Vadlamani, Venkat; Rahman, Taufiq; Chee, Xavier; Gunasinge, Kavinda; Harper, Matthew [0000-0002-4740-637X]
CD39 (ectonucleoside triphosphate diphosphohydrolase-1; ENTPD1) metabolizes extracellular ATP and ADP to AMP. AMP is subsequently metabolized by CD79 to adenosine. CD39 activity is therefore a key regulator of purinergic signalling in cancer, thrombosis, and autoimmune diseases. In this study we demonstrate that soluble, recombinant CD39 shows substrate inhibition with ADP or ATP as the substrate. Although CD39 activity initially increased with increasing substrate concentration, at high concentrations of ATP or ADP, CD39 activity was markedly reduced. Although the reaction product, AMP, inhibits CD39 activity, insufficient AMP was generated under our conditions to account for the substrate inhibition seen. In contrast, inhibition was not seen with UDP or UTP as substrates. 2-methylthio-ADP also showed no substrate inhibition, indicating the nucleotide base is an important determinant of substrate inhibition. Molecular dynamics simulations revealed that ADP can undergo conformational rearrangements within the CD39 active site that were not seen with UDP or 2-methylthio-ADP. Appreciating the existence of substrate inhibition of CD39 will help the interpretation of studies of CD39 activity, including investigations into drugs that modulate CD39 activity.
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Extension of a hybrid FE-SEA approach for vibro-acoustic analysis with prescribed displacements
(Elsevier BV, 2022) Andrade, L; Langley, RS; Butlin, T; Andrade, L [0000-0003-0679-9354]; Langley, RS [0000-0001-9978-9790]; Butlin, T [0000-0002-7814-8107]
A hybrid Finite Element-Statistical Energy Analysis (FE-SEA) method has been developed and improved over the past fifteen years to analyse complex vibro-acoustic built-up systems, comprised by both deterministic and statistical components, and the FE-SEA equations have been derived considering that the power input to the structure is due to prescribed forces applied to the degrees of freedom of either the deterministic and/or the statistical components. In this paper, it is presented a generalised set of FE-SEA equations to estimate the response of a system when prescribed displacements contribute to the power input to the complex system. It was found that the equations are not necessarily reversible, meaning that if a set of displacements estimated from the hybrid approach with prescribed forces are used as input to the same randomised structure, the response will be altered due to its statistical nature. The generalised set of FE-SEA equations is validated against numerical data of FE Monte Carlo simulations of two complex built-up structures, where the input is given to the statistical system and to a deterministic resonant structure, respectively.

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