• Waiting for Brexit: Crisis, conjuncture, method

      Hall, Sarah Marie; orcid: 0000-0002-6379-4544; email: sarah.m.hall@manchester.ac.uk (2021-10-20)
      Abstract: UK geopolitics for the last five years has been heavily dominated by Brexit. The lead up to the referendum, the result, negotiations, intervening general election, extensions, further negotiations, and impending exit from the European Union have captured both academic and public interest. This paper contributes to geographical and wider social science research on the everyday geographies of socio‐economic change, with a particular focus on Brexit and the temporal politics of waiting. Emerging analyses focus on Brexit as an event, as uncertainty, and a discrete period for and of research on public moods. I illustrate how exploring Brexit through the lens of waiting provides new ways of thinking through the time‐spaces of Brexit, by drawing on data collected during an ethnographic participatory project in Gorse Hill, Greater Manchester (2018–2020). Analysis of group discussions, peer‐led research projects, podcast recordings, vox pops, and ethnographic fieldnotes highlight the embodied, everyday, endured, and emplaced experience of waiting for Brexit. More specifically, findings make the case for this waiting as crisis, as conjuncture, and as method. The paper closes with a discussion of the pace and timeliness of research, and the implications of waiting for, in, and with Brexit and other forms of socio‐economic change.
    • A prospective cohort study providing insights for markers of adverse pregnancy outcome in older mothers

      Lean, Samantha C.; Jones, Rebecca L.; Roberts, Stephen A.; Heazell, Alexander E. P.; email: alexander.heazell@manchester.ac.uk (BioMed Central, 2021-10-20)
      Abstract: Background: Advanced maternal age (≥35 years) is associated with increased rates of adverse pregnancy outcome. Better understanding of underlying pathophysiological processes may improve identification of older mothers who are at greatest risk. This study aimed to investigate changes in oxidative stress and inflammation in older women and identify clinical and biochemical predictors of adverse pregnancy outcome in older women. Methods: The Manchester Advanced Maternal Age Study (MAMAS) was a multicentre, observational, prospective cohort study of 528 mothers. Participants were divided into three age groups for comparison 20–30 years (n = 154), 35–39 years (n = 222) and ≥ 40 years (n = 152). Demographic and medical data were collected along with maternal blood samples at 28 and 36 weeks’ gestation. Multivariable analysis was conducted to identify variables associated with adverse outcome, defined as one or more of: small for gestational age (< 10th centile), FGR (<5th centile), stillbirth, NICU admission, preterm birth < 37 weeks’ gestation or Apgar score < 7 at 5 min. Biomarkers of inflammation, oxidative stress and placental dysfunction were quantified in maternal serum. Univariate and multivariable logistic regression was used to identify associations with adverse fetal outcome. Results: Maternal smoking was associated with adverse outcome irrespective of maternal age (Adjusted Odds Ratio (AOR) 4.22, 95% Confidence Interval (95%CI) 1.83, 9.75), whereas multiparity reduced the odds (AOR 0.54, 95% CI 0.33, 0.89). In uncomplicated pregnancies in older women, lower circulating anti-inflammatory IL-10, IL-RA and increased antioxidant capacity (TAC) were seen. In older mothers with adverse outcome, TAC and oxidative stress markers were increased and levels of maternal circulating placental hormones (hPL, PlGF and sFlt-1) were reduced (p < 0.05). However, these biomarkers only had modest predictive accuracy, with the largest area under the receiver operator characteristic (AUROC) of 0.74 for placental growth factor followed by TAC (AUROC = 0.69). Conclusions: This study identified alterations in circulating inflammatory and oxidative stress markers in older women with adverse outcome providing preliminary evidence of mechanistic links. Further, larger studies are required to determine if these markers can be developed into a predictive model of an individual older woman’s risk of adverse pregnancy outcome, enabling a reduction in stillbirth rates whilst minimising unnecessary intervention.
    • Palladium-doped hierarchical ZSM-5 for catalytic selective oxidation of allylic and benzylic alcohols

      Ding, Shengzhe; orcid: 0000-0003-2822-3882; Ganesh, Muhammad; Jiao, Yilai; Ou, Xiaoxia; Isaacs, Mark A.; orcid: 0000-0002-0335-4272; S'ari, Mark; Torres Lopez, Antonio; orcid: 0000-0001-7378-1811; Fan, Xiaolei; orcid: 0000-0002-9039-6736; email: xiaolei.fan@manchester.ac.uk; Parlett, Christopher M. A.; orcid: 0000-0002-3651-7314; email: christopher.parlett@manchester.ac.uk (The Royal Society, 2021-10-20)
      Hierarchical zeolites have the potential to provide a breakthrough in transport limitation, which hinders pristine microporous zeolites and thus may broaden their range of applications. We have explored the use of Pd-doped hierarchical ZSM-5 zeolites for aerobic selective oxidation (selox) of cinnamyl alcohol and benzyl alcohol to their corresponding aldehydes. Hierarchical ZSM-5 with differing acidity (H-form and Na-form) were employed and compared with two microporous ZSM-5 equivalents. Characterization of the four catalysts by X-ray diffraction, nitrogen porosimetry, NH3 temperature-programmed desorption, CO chemisorption, high-resolution scanning transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy allowed investigation of their porosity, acidity, as well as Pd active sites. The incorporation of complementary mesoporosity, within the hierarchical zeolites, enhances both active site dispersion and PdO active site generation. Likewise, alcohol conversion was also improved with the presence of secondary mesoporosity, while strong Brønsted acidity, present solely within the H-form systems, negatively impacted overall selectivity through undesirable self-etherification. Therefore, tuning support porosity and acidity alongside active site dispersion is paramount for optimal aldehyde production.
    • The Wiener–Hopf technique, its generalizations and applications: constructive and approximate methods

      Kisil, Anastasia V.; orcid: 0000-0001-7652-5880; email: anastasia.kisil@manchester.ac.uk; Abrahams, I. David; Mishuris, Gennady; orcid: 0000-0003-2565-1961; Rogosin, Sergei V.; orcid: 0000-0002-7356-1656 (The Royal Society, 2021-10-20)
      This paper reviews the modern state of the Wiener–Hopf factorization method and its generalizations. The main constructive results for matrix Wiener–Hopf problems are presented, approximate methods are outlined and the main areas of applications are mentioned. The aim of the paper is to offer an overview of the development of this method, and demonstrate the importance of bringing together pure and applied analysis to effectively employ the Wiener–Hopf technique.
    • Prospects of Integrated Photovoltaic-Fuel Cell Systems in a Hydrogen Economy: A Comprehensive Review

      Ogbonnaya, Chukwuma; orcid: 0000-0003-4756-6485; email: chukwuma.ogbonnaya@manchester.ac.uk; Abeykoon, Chamil; orcid: 0000-0002-6797-776X; email: chamil.abeykoon@manchester.ac.uk; Nasser, Adel; orcid: 0000-0003-1609-1384; email: a.g.nasser@manchester.ac.uk; Turan, Ali; orcid: 0000-0001-9225-6668; email: a.turan@ntlworld.com; Ume, Cyril Sunday; email: cyril.ume@funai.edu.ng (MDPI, 2021-10-19)
      Integrated photovoltaic-fuel cell (IPVFC) systems, amongst other integrated energy generation methodologies are renewable and clean energy technologies that have received diverse research and development attentions over the last few decades due to their potential applications in a hydrogen economy. This article systematically updates the state-of-the-art of IPVFC systems and provides critical insights into the research and development gaps needed to be filled/addressed to advance these systems towards full commercialization. Design methodologies, renewable energy-based microgrid and off-grid applications, energy management strategies, optimizations and the prospects as self-sustaining power sources were covered. IPVFC systems could play an important role in the upcoming hydrogen economy since they depend on solar hydrogen which has almost zero emissions during operation. Highlighted herein are the advances as well as the technical challenges to be surmounted to realize numerous potential applications of IPVFC systems in unmanned aerial vehicles, hybrid electric vehicles, agricultural applications, telecommunications, desalination, synthesis of ammonia, boats, buildings, and distributed microgrid applications.
    • Altered protein O-GlcNAcylation in placentas from mothers with diabetes causes aberrant endocytosis in placental trophoblast cells

      Palin, Victoria; Russell, Matthew; Graham, Robert; Aplin, John D.; Westwood, Melissa; email: melissa.westwood@manchester.ac.uk (Nature Publishing Group UK, 2021-10-19)
      Abstract: Women with pre-existing diabetes have an increased risk of poor pregnancy outcomes, including disordered fetal growth, caused by changes to placental function. Here we investigate the possibility that the hexosamine biosynthetic pathway, which utilises cellular nutrients to regulate protein function via post-translationally modification with O-linked N-acetylglucosamine (GlcNAc), mediates the placental response to the maternal metabolic milieu. Mass spectrometry analysis revealed that the placental O-GlcNAcome is altered in women with type 1 (n = 6) or type 2 (n = 6) diabetes T2D (≥ twofold change in abundance in 162 and 165 GlcNAcylated proteins respectively compared to BMI-matched controls n = 11). Ingenuity pathway analysis indicated changes to clathrin-mediated endocytosis (CME) and CME-associated proteins, clathrin, Transferrin (TF), TF receptor and multiple Rabs, were identified as O-GlcNAcylation targets. Stimulating protein O-GlcNAcylation using glucosamine (2.5 mM) increased the rate of TF endocytosis by human placental cells (p = 0.02) and explants (p = 0.04). Differential GlcNAcylation of CME proteins suggests altered transfer of cargo by placentas of women with pre-gestational diabetes, which may contribute to alterations in fetal growth. The human placental O-GlcNAcome provides a resource to aid further investigation of molecular mechanisms governing placental nutrient sensing.
    • Correction to: Symptoms in first-degree relatives of patients with rheumatoid arthritis: evaluation of cross-sectional data from the symptoms in persons at risk of rheumatoid arthritis (SPARRA) questionnaire in the Preclinical EValuation of Novel Targets in RA (PREVeNT-RA) Cohort

      Costello, R. E.; Humphreys, J. H.; Sergeant, J. C.; Haris, M.; Stirling, F.; Raza, K.; van Schaardenburg, D.; Bruce, Ian N.; email: ian.bruce@manchester.ac.uk (BioMed Central, 2021-10-19)
      An amendment to this paper has been published and can be accessed via the original article.
    • Relationship between the Plasma Proteome and Changes in Inflammatory Markers after Bariatric Surgery

      Fachim; email: helene.fachim@manchester.ac.uk; Iqbal; email: zohaib@doctors.org.uk; Gibson; email: martin.gibson@manchester.ac.uk; Baricevic-Jones; email: ivona.baricevic-jones@manchester.ac.uk; Campbell; email: amy.campbell@manchester.ac.uk; Geary; orcid: 0000-0002-5592-5532; email: bethany.geary@manchester.ac.uk; Syed; orcid: 0000-0001-8696-7121; email: akheel.syed@manchester.ac.uk; Whetton; orcid: 0000-0002-1098-3878; email: tony.whetton@manchester.ac.uk; Soran; email: handrean.soran@mft.nhs.uk; Donn; orcid: 0000-0001-6976-9828; email: Rachelle.donn@manchester.ac.uk; et al. (MDPI, 2021-10-19)
      Severe obesity is a disease associated with multiple adverse effects on health. Metabolic bariatric surgery (MBS) can have significant effects on multiple body systems and was shown to improve inflammatory markers in previous short-term follow-up studies. We evaluated associations between changes in inflammatory markers (CRP, IL6 and TNFα) and circulating proteins after MBS. Methods: Sequential window acquisition of all theoretical mass spectra (SWATH-MS) proteomics was performed on plasma samples taken at baseline (pre-surgery) and 6 and 12 months after MBS, and concurrent analyses of inflammatory/metabolic parameters were carried out. The change in absolute abundances of those proteins, showing significant change at both 6 and 12 months, was tested for correlation with the absolute and percentage (%) change in inflammatory markers. Results: We found the following results: at 6 months, there was a correlation between %change in IL-6 and fold change in HSPA4 (rho = −0.659; p = 0.038) and in SERPINF1 (rho = 0.714, p = 0.020); at 12 months, there was a positive correlation between %change in IL-6 and fold change in the following proteins—LGALS3BP (rho = 0.700, p = 0.036), HSP90B1 (rho = 0.667; p = 0.05) and ACE (rho = 0.667, p = 0.05). We found significant inverse correlations at 12 months between %change in TNFα and the following proteins: EPHX2 and ACE (for both rho = −0.783, p = 0.013). We also found significant inverse correlations between %change in CRP at 12 months and SHBG (rho = −0.759, p = 0.029), L1CAM (rho = −0.904, p = 0.002) and AMBP (rho = −0.684, p = 0.042). Conclusion: Using SWATH-MS, we identified several proteins that are involved in the inflammatory response whose levels change in patients who achieve remission of T2DM after bariatric surgery in tandem with changes in IL6, TNFα and/or CRP. Future studies are needed to clarify the underlying mechanisms in how MBS decreases low-grade inflammation.
    • Comparison of in silico strategies to prioritize rare genomic variants impacting RNA splicing for the diagnosis of genomic disorders

      Rowlands, Charlie; Thomas, Huw B.; Lord, Jenny; Wai, Htoo A.; Arno, Gavin; Beaman, Glenda; Sergouniotis, Panagiotis; Gomes-Silva, Beatriz; Campbell, Christopher; Gossan, Nicole; et al. (Nature Publishing Group UK, 2021-10-18)
      Abstract: The development of computational methods to assess pathogenicity of pre-messenger RNA splicing variants is critical for diagnosis of human disease. We assessed the capability of eight algorithms, and a consensus approach, to prioritize 249 variants of uncertain significance (VUSs) that underwent splicing functional analyses. The capability of algorithms to differentiate VUSs away from the immediate splice site as being ‘pathogenic’ or ‘benign’ is likely to have substantial impact on diagnostic testing. We show that SpliceAI is the best single strategy in this regard, but that combined usage of tools using a weighted approach can increase accuracy further. We incorporated prioritization strategies alongside diagnostic testing for rare disorders. We show that 15% of 2783 referred individuals carry rare variants expected to impact splicing that were not initially identified as ‘pathogenic’ or ‘likely pathogenic’; one in five of these cases could lead to new or refined diagnoses.
    • Mutational Characterization of Cutaneous Melanoma Supports Divergent Pathways Model for Melanoma Development

      Millán-Esteban, David; orcid: 0000-0002-8066-1444; email: david.millan@ucv.es; Peña-Chilet, María; orcid: 0000-0002-6445-9617; email: maria.pena.chilet.ext@juntadeandalucia.es; García-Casado, Zaida; email: zgarcia@fivo.org; Manrique-Silva, Esperanza; email: emanrique@fivo.org; Requena, Celia; email: crequena@fivo.org; Bañuls, José; orcid: 0000-0002-0990-7608; email: banuls_jos@gva.es; López-Guerrero, Jose Antonio; orcid: 0000-0002-7369-8388; email: jalopez@fivo.org; Rodríguez-Hernández, Aranzazu; email: arodriguezh@fivo.org; Traves, Víctor; email: vtraves@fivo.org; Dopazo, Joaquín; orcid: 0000-0003-3318-120X; email: joaquin.dopazo@juntadeandalucia.es; et al. (MDPI, 2021-10-18)
      According to the divergent pathway model, cutaneous melanoma comprises a nevogenic group with a propensity to melanocyte proliferation and another one associated with cumulative solar damage (CSD). While characterized clinically and epidemiologically, the differences in the molecular profiles between the groups have remained primarily uninvestigated. This study has used a custom gene panel and bioinformatics tools to investigate the potential molecular differences in a thoroughly characterized cohort of 119 melanoma patients belonging to nevogenic and CSD groups. We found that the nevogenic melanomas had a restricted set of mutations, with the prominently mutated gene being BRAF. The CSD melanomas, in contrast, showed mutations in a diverse group of genes that included NF1, ROS1, GNA11, and RAC1. We thus provide evidence that nevogenic and CSD melanomas constitute different biological entities and highlight the need to explore new targeted therapies.
    • Replication catastrophe is responsible for intrinsic PAR glycohydrolase inhibitor-sensitivity in patient-derived ovarian cancer models

      Coulson-Gilmer, Camilla; Morgan, Robert D.; Nelson, Louisa; Barnes, Bethany M.; Tighe, Anthony; Wardenaar, René; Spierings, Diana C. J.; Schlecht, Helene; Burghel, George J.; Foijer, Floris; et al. (BioMed Central, 2021-10-16)
      Abstract: Background: Patients with ovarian cancer often present at advanced stage and, following initial treatment success, develop recurrent drug-resistant disease. PARP inhibitors (PARPi) are yielding unprecedented survival benefits for women with BRCA-deficient disease. However, options remain limited for disease that is platinum-resistant and/or has inherent or acquired PARPi-resistance. PARG, the PAR glycohydrolase that counterbalances PARP activity, is an emerging target with potential to selectively kill tumour cells harbouring oncogene-induced DNA replication and metabolic vulnerabilities. Clinical development of PARG inhibitors (PARGi) will however require predictive biomarkers, in turn requiring an understanding of their mode of action. Furthermore, differential sensitivity to PARPi is key for expanding treatment options available for patients. Methods: A panel of 10 ovarian cancer cell lines and a living biobank of patient-derived ovarian cancer models (OCMs) were screened for PARGi-sensitivity using short- and long-term growth assays. PARGi-sensitivity was characterized using established markers for DNA replication stress, namely replication fibre asymmetry, RPA foci, KAP1 and Chk1 phosphorylation, and pan-nuclear γH2AX, indicating DNA replication catastrophe. Finally, gene expression in sensitive and resistant cells was also examined using NanoString or RNAseq. Results: PARGi sensitivity was identified in both ovarian cancer cell lines and patient-derived OCMs, with sensitivity accompanied by markers of persistent replication stress, and a pre-mitotic cell cycle block. Moreover, DNA replication genes are down-regulated in PARGi-sensitive cell lines consistent with an inherent DNA replication vulnerability. However, DNA replication gene expression did not predict PARGi-sensitivity in OCMs. The subset of patient-derived OCMs that are sensitive to single-agent PARG inhibition, includes models that are PARPi- and/or platinum-resistant, indicating that PARG inhibitors may represent an alternative treatment strategy for women with otherwise limited therapeutic options. Conclusions: We discover that a subset of ovarian cancers are intrinsically sensitive to pharmacological PARG blockade, including drug-resistant disease, underpinned by a common mechanism of replication catastrophe. We explore the use of a transcript-based biomarker, and provide insight into the design of future clinical trials of PARGi in patients with ovarian cancer. However, our results highlight the complexity of developing a predictive biomarker for PARGi sensitivity.
    • The Effect of Authigenic Clays on Fault Zone Permeability

      Farrell, N. J. C.; orcid: 0000-0002-8491-9094; email: natalie.farrell@manchester.ac.uk; Debenham, N.; Wilson, L.; Wilson, M. J.; Healy, D.; orcid: 0000-0003-2685-1498; King, R. C.; Holford, S. P.; orcid: 0000-0002-4524-8822; Taylor, C. W. (2021-10-15)
      Abstract: Clays are understood to form the majority of fluid‐flow barriers in faulted reservoirs and numerous fault gouge and fault seal studies have quantified the volumes of smeared and abraded clays create fluid‐flow barriers along fault surfaces. However, clay‐related permeability adjacent to the fault surface, including in the fault damage zone, has largely been neglected. Previous studies have shown the morphology and distribution of unfaulted authigenic clays, and not just clay volume, exert a significant control on the magnitude of permeability. However, fault‐related studies have neither characterized deformed authigenic clays nor addressed their influence on fluid‐flow. In this study laboratory permeabilities of faulted, authigenic clay bearing sandstones sampled from the Otway basin (Australia) and the Orcadian basin (UK) present trends which; (a) do not correspond to expected patterns of fluid‐flow in faulted clay‐bearing sandstones and, (b) cannot be explained using published models of permeability related to changing clay volume. Microscopic analysis shows that faulting has disaggregated authigenic clays and, similarly to framework grain deformation, comminuted and sheared clay grains. However, instead of impeding fluid‐flow, analysis of pore networks (using mercury injection porosimetry) showed that faulting of authigenic clays has increased pore connectivity, contributing to increased magnitude of permeability and development of permeability anisotropy. Contrary to published results of faulting and fluid‐flow in impure sandstones, our results show that fault related processes involving the formation of clays in the fault zone can increase permeability and reduce the capillary threshold pressures of fault rocks relative to the unfaulted host rock.
    • The impact of COVID-19 on digital data practices in museums and art galleries in the UK and the US

      Noehrer, Lukas; orcid: 0000-0002-9167-0397; email: lukas.noehrer@manchester.ac.uk; Gilmore, Abigail; Jay, Caroline; Yehudi, Yo; orcid: 0000-0003-2705-1724 (Palgrave Macmillan UK, 2021-10-15)
      Abstract: The first quarter of 2020 heralded the beginning of an uncertain future for museums and galleries as the COVID-19 pandemic hit and the only means to stay ‘open’ was to turn towards the digital. In this paper, we investigate how the physical closure of museum buildings due to lockdown restrictions caused shockwaves within their digital strategies and changed their data practices potentially for good. We review the impact of COVID-19 on the museum sector, based on literature and desk research, with a focus on the implications for three museums and art galleries in the United Kingdom and the United States, and their mission, objectives, and digital data practices. We then present an analysis of ten qualitative interviews with expert witnesses working in the sector, representing different roles and types of institutions, undertaken between April and October 2020. Our research finds that digital engagement with museum content and practices around data in institutions have changed and that digital methods for organising and accessing collections for both staff and the general public have become more important. We present evidence that strategic preparedness influenced how well institutions were able to transition during closure and that metrics data became pivotal in understanding this novel situation. Increased engagement online changed traditional audience profiles, challenging museums to find ways of accommodating new forms of engagement in order to survive and thrive in the post-pandemic environment.
    • Stress Corrosion Cracking of Additively Manufactured Alloy 625

      Cabrini, Marina; orcid: 0000-0003-3901-8657; email: marina.cabrini@unibg.it; Lorenzi, Sergio; orcid: 0000-0002-1337-7590; email: sergio.lorenzi@unibg.it; Testa, Cristian; orcid: 0000-0002-6064-9851; email: cristian.testa@guest.unibg.it; Carugo, Francesco; email: francesco.carugo@unibg.it; Pastore, Tommaso; orcid: 0000-0002-1443-7786; email: tommaso.pastore@unibg.it; Manfredi, Diego; orcid: 0000-0002-2876-143X; email: diego.manfredi@polito.it; Biamino, Sara; orcid: 0000-0003-1840-7717; email: sara.biamino@polito.it; Marchese, Giulio; orcid: 0000-0002-4637-5532; email: giulio.marchese@polito.it; Parizia, Simone; orcid: 0000-0002-1616-2800; email: simone.parizia@polito.it; Scenini, Fabio; orcid: 0000-0002-8974-4860; email: fabio.scenini@manchester.ac.uk (MDPI, 2021-10-15)
      Laser bed powder fusion (LPBF) is an additive manufacturing technology for the fabrication of semi-finished components directly from computer-aided design modelling, through melting and consolidation, layer upon layer, of a metallic powder, with a laser source. This manufacturing technique is particularly indicated for poor machinable alloys, such as Alloy 625. However, the unique microstructure generated could modify the resistance of the alloy to environment assisted cracking. The aim of this work was to analyze the stress corrosion cracking (SCC) and hydrogen embrittlement resistance behavior of Alloy 625 obtained by LPBF, both in as-built condition and after a standard heat treatment (grade 1). U-bend testing performed in boiling magnesium chloride at 155 and 170 °C confirmed the immunity of the alloy to SCC. However, slow strain rate tests in simulated ocean water on cathodically polarized specimens highlighted the possibility of the occurrence of hydrogen embrittlement in a specific range of strain rate and cathodic polarization. The very fine grain size and dislocation density of the thermally untreated specimens appeared to increase the hydrogen diffusion and embrittlement effect on pre-charged specimens that were deformed at the high strain rate. Conversely, heat treatment appeared to mitigate hydrogen embrittlement at high strain rates, however at the slow strain rate all the specimens showed a similar behavior.
    • Genetic and process engineering strategies for enhanced recombinant N -glycoprotein production in bacteria

      Pratama, Fenryco; Linton, Dennis; Dixon, Neil; orcid: 0000-0001-9065-6764; email: neil.dixon@manchester.ac.uk (BioMed Central, 2021-10-14)
      Abstract: Background: The production of N-linked glycoproteins in genetically amenable bacterial hosts offers great potential for reduced cost, faster/simpler bioprocesses, greater customisation, and utility for distributed manufacturing of glycoconjugate vaccines and glycoprotein therapeutics. Efforts to optimize production hosts have included heterologous expression of glycosylation enzymes, metabolic engineering, use of alternative secretion pathways, and attenuation of gene expression. However, a major bottleneck to enhance glycosylation efficiency, which limits the utility of the other improvements, is the impact of target protein sequon accessibility during glycosylation. Results: Here, we explore a series of genetic and process engineering strategies to increase recombinant N-linked glycosylation, mediated by the Campylobacter-derived PglB oligosaccharyltransferase in Escherichia coli. Strategies include increasing membrane residency time of the target protein by modifying the cleavage site of its secretion signal, and modulating protein folding in the periplasm by use of oxygen limitation or strains with compromised oxidoreductase or disulphide-bond isomerase activity. These approaches achieve up to twofold improvement in glycosylation efficiency. Furthermore, we also demonstrate that supplementation with the chemical oxidant cystine enhances the titre of glycoprotein in an oxidoreductase knockout strain by improving total protein production and cell fitness, while at the same time maintaining higher levels of glycosylation efficiency. Conclusions: In this study, we demonstrate that improved protein glycosylation in the heterologous host could be achieved by mimicking the coordination between protein translocation, folding and glycosylation observed in native host such as Campylobacter jejuni and mammalian cells. Furthermore, it provides insight into strain engineering and bioprocess strategies, to improve glycoprotein yield and titre, and to avoid physiological burden of unfolded protein stress upon cell growth. The process and genetic strategies identified herein will inform further optimisation and scale-up of heterologous recombinant N-glycoprotein production.
    • Corneal nerve loss is related to the severity of painful diabetic neuropathy

      Kalteniece, Alise; Ferdousi, Maryam; Azmi, Shazli; Khan, Saif Ullah; Worthington, Anne; Marshall, Andrew; Faber, Catharina G.; Lauria, Giuseppe; orcid: 0000-0001-9773-020X; Boulton, Andrew J. M.; Soran, Handrean; et al. (2021-10-13)
      Abstract: Background and purpose: Previously it has been shown that patients with painful diabetic neuropathy (PDN) have greater corneal nerve loss compared to patients with painless diabetic neuropathy. This study investigated if the severity of corneal nerve loss was related to the severity of PDN. Methods: Participants with diabetic neuropathy (n = 118) and healthy controls (n = 38) underwent clinical and neurological evaluation, quantitative sensory testing, nerve conduction testing and corneal confocal microscopy and were categorized into those with no (n = 43), mild (n = 34) and moderate‐to‐severe (n = 41) neuropathic pain. Results: Corneal nerve fibre density (p = 0.003), corneal nerve fibre length (p < 0.0001) and cold perception threshold (p < 0.0001) were lower and warm perception threshold was higher (p = 0.002) in patients with more severe pain, but there was no significant difference in the neuropathy disability score (p = 0.5), vibration perception threshold (p = 0.5), sural nerve conduction velocity (p = 0.3) and amplitude (p = 0.7), corneal nerve branch density (p = 0.06) and deep breathing heart rate variability (p = 0.08) between patients with differing severity of PDN. The visual analogue scale correlated significantly with corneal nerve fibre density (r = −0.3, p = 0.0002), corneal nerve branch density (r = −0.3, p = 0.001) and corneal nerve fibre length (r = −0.4, p < 0.0001). Receiver operating curve analysis showed that corneal nerve fibre density had an area under the curve of 0.78 with a sensitivity of 0.73 and specificity of 0.72 for the diagnosis of PDN. Conclusions: Corneal confocal microscopy reveals increasing corneal nerve fibre loss with increasing severity of neuropathic pain and a good diagnostic outcome for identifying patients with PDN.
    • Nitric oxide mediates activity-dependent change to synaptic excitation during a critical period in Drosophila

      Giachello, Carlo N. G.; Fan, Yuen Ngan; Landgraf, Matthias; Baines, Richard A.; email: Richard.Baines@manchester.ac.uk (Nature Publishing Group UK, 2021-10-13)
      Abstract: The emergence of coordinated network function during nervous system development is often associated with critical periods. These phases are sensitive to activity perturbations during, but not outside, of the critical period, that can lead to permanently altered network function for reasons that are not well understood. In particular, the mechanisms that transduce neuronal activity to regulating changes in neuronal physiology or structure are not known. Here, we take advantage of a recently identified invertebrate model for studying critical periods, the Drosophila larval locomotor system. Manipulation of neuronal activity during this critical period is sufficient to increase synaptic excitation and to permanently leave the locomotor network prone to induced seizures. Using genetics and pharmacological manipulations, we identify nitric oxide (NO)-signaling as a key mediator of activity. Transiently increasing or decreasing NO-signaling during the critical period mimics the effects of activity manipulations, causing the same lasting changes in synaptic transmission and susceptibility to seizure induction. Moreover, the effects of increased activity on the developing network are suppressed by concomitant reduction in NO-signaling and enhanced by additional NO-signaling. These data identify NO signaling as a downstream effector, providing new mechanistic insight into how activity during a critical period tunes a developing network.
    • Environmental Assessment of Latent Heat Thermal Energy Storage Technology System with Phase Change Material for Domestic Heating Applications

      Chocontá Bernal, Daniel; email: Daniel.chocontabernal@postgrad.manchester.ac.uk; Muñoz, Edmundo; orcid: 0000-0002-7258-6069; email: edmundo.munoz@unab.cl; Manente, Giovanni; orcid: 0000-0001-7134-8731; email: G.Manente@bham.ac.uk; Sciacovelli, Adriano; orcid: 0000-0001-9684-3122; email: a.sciacovelli@bham.ac.uk; Ameli, Hossein; orcid: 0000-0003-4056-9819; email: h.ameli14@imperial.ac.uk; Gallego-Schmid, Alejandro; email: alejandro.gallegoschmid@manchester.ac.uk (MDPI, 2021-10-13)
      The emissions generated by the space and water heating of UK homes need to be reduced to meet the goal of becoming carbon neutral by 2050. The combination of solar (S) collectors with latent heat thermal energy storage (LHTES) technologies with phase change materials (PCM) can potentially help to achieve this goal. However, there is limited understanding of the environmental sustainability of LHTES technologies from a full life cycle perspective. This study assesses for the first time 18 environmental impacts of a full S-LHTES-PCM system from a cradle to grave perspective and compares the results with the most common sources of heat in UK homes. The results show that the system’s main environmental hotspots are the solar collector, the PCM, the PCM tank, and the heat exchanger. The main cause of most of the impacts is the extensive consumption of electricity and heat during the production of raw materials for these components. The comparison with other sources of household heat (biomass, heat pump, and natural gas) indicates that the S-LHTES-PCM system generates the highest environmental impact in 11 of 18 categories. However, a sensitivity analysis based on the lifetime of the S-LHTES-PCM systems shows that, when the lifetime increases to 40 years, almost all the impacts are significantly reduced. In fact, a 40-year S-LHTES-PCM system has a lower global warming potential than natural gas.
    • Investigating top tagging with Y m -Splitter and N-subjettiness

      Dasgupta, Mrinal; Helliwell, Jack; orcid: 0000-0002-8725-7794; email: jack.helliwell@manchester.ac.uk (Springer Berlin Heidelberg, 2021-10-12)
      Abstract: We study top-tagging from an analytical QCD perspective focussing on the role of two key steps therein: a step to find three-pronged substructure and a step that places constraints on radiation. For the former we use a recently introduced modification of Y-Splitter, known as Ym-Splitter, and for the latter we use the well-known N-subjettiness variable. We derive resummed results for this combination of variables for both signal jets and background jets, also including pre-grooming of the jet. Our results give new insight into the performance of top tagging tools in particular with regard to the role of the distinct steps involved.
    • Estimating stochastic survey response errors using the multitrait‐multierror model

      Cernat, Alexandru; orcid: 0000-0003-2176-1215; email: alexandru.cernat@manchester.ac.uk; Oberski, Daniel L.; orcid: 0000-0001-7467-2297 (2021-10-12)
      Abstract: Surveys are well known to contain response errors of different types, including acquiescence, social desirability, common method variance and random error simultaneously. Nevertheless, a single error source at a time is all that most methods developed to estimate and correct for such errors consider in practice. Consequently, estimation of response errors is inefficient, their relative importance is unknown and the optimal question format may not be discoverable. To remedy this situation, we demonstrate how multiple types of errors can be estimated concurrently with the recently introduced ‘multitrait‐multierror’ (MTME) approach. MTME combines the theory of design of experiments with latent variable modelling to estimate response error variances of different error types simultaneously. This allows researchers to evaluate which errors are most impactful, and aids in the discovery of optimal question formats. We apply this approach using representative data from the United Kingdom to six survey items measuring attitudes towards immigrants that are commonly used across public opinion studies.