• Sarcopenia during COVID-19 lockdown restrictions: long-term health effects of short-term muscle loss

      Kirwan, Richard; orcid: 0000-0003-4645-0077; email: r.p.kirwan@2018.ljmu.ac.uk; McCullough, Deaglan; orcid: 0000-0002-9882-9639; Butler, Tom; orcid: 0000-0003-0818-1566; email: t.butler@chester.ac.uk; Perez de Heredia, Fatima; orcid: 0000-0002-2537-3327; Davies, Ian G.; orcid: 0000-0003-3722-8466; Stewart, Claire; orcid: 0000-0002-8104-4819 (Springer International Publishing, 2020-10-01)
      Abstract: The COVID-19 pandemic is an extraordinary global emergency that has led to the implementation of unprecedented measures in order to stem the spread of the infection. Internationally, governments are enforcing measures such as travel bans, quarantine, isolation, and social distancing leading to an extended period of time at home. This has resulted in reductions in physical activity and changes in dietary intakes that have the potential to accelerate sarcopenia, a deterioration of muscle mass and function (more likely in older populations), as well as increases in body fat. These changes in body composition are associated with a number of chronic, lifestyle diseases including cardiovascular disease (CVD), diabetes, osteoporosis, frailty, cognitive decline, and depression. Furthermore, CVD, diabetes, and elevated body fat are associated with greater risk of COVID-19 infection and more severe symptomology, underscoring the importance of avoiding the development of such morbidities. Here we review mechanisms of sarcopenia and their relation to the current data on the effects of COVID-19 confinement on physical activity, dietary habits, sleep, and stress as well as extended bed rest due to COVID-19 hospitalization. The potential of these factors to lead to an increased likelihood of muscle loss and chronic disease will be discussed. By offering a number of home-based strategies including resistance exercise, higher protein intakes and supplementation, we can potentially guide public health authorities to avoid a lifestyle disease and rehabilitation crisis post-COVID-19. Such strategies may also serve as useful preventative measures for reducing the likelihood of sarcopenia in general and in the event of future periods of isolation.
    • Sarcopenia estimation using psoas major enhances P-POSSUM mortality prediction in older patients undergoing emergency laparotomy: cross-sectional study.

      Simpson, Gregory; orcid: 0000-0002-9779-1747; email: gregorysimpson@doctors.org.uk; Wilson, Jeremy; Vimalachandran, Dale; McNicol, Frances; Magee, Conor (2021-04-21)
      Emergency laparotomy is a considerable component of a colorectal surgeon's workload and conveys substantial morbidity and mortality, particularly in older patients. Frailty is associated with poorer surgical outcomes. Frailty and sarcopenia assessment using Computed Tomography (CT) calculation of psoas major area predicts outcomes in elective and emergency surgery. Current risk predictors do not incorporate frailty metrics. We investigated whether sarcopenia measurement enhanced mortality prediction in over-65 s who underwent emergency laparotomy and emergency colorectal resection. An analysis of data collected prospectively during the National Emergency Laparotomy Audit (NELA) was conducted. Psoas major (PM) cross-sectional area was measured at the L3 level and a ratio of PM to L3 vertebral body area (PML3) was calculated. Outcome measures included inpatient, 30-day and 90-day mortality. Statistical analysis was conducted using Mann-Whitney, Chi-squared and receiver operating characteristics (ROC). Logistic regression was conducted using P-POSSUM variables with and without the addition of PML3. Nine-hundred and forty-four over-65 s underwent emergency laparotomy from three United Kingdom hospitals were included. Median age was 76 years (IQR 70-82 years). Inpatient mortality was 21.9%, 30-day mortality was 16.3% and 90-day mortality was 20.7%. PML3 less than 0.39 for males and 0.31 for females indicated significantly worse outcomes (inpatient mortality 68% vs 5.6%, 30-day mortality 50.6% vs 4.0%,90-day mortality 64% vs 5.2%, p < 0.0001). PML3 was independently associated with mortality in multivariate analysis (p < 0.0001). Addition of PML3 to P-POSSUM variables improved area under the curve (AUC) on ROC analysis for inpatient mortality (P-POSSUM:0.78 vs P-POSSUM + PML3:0.917), 30-day mortality(P-POSSUM:0.802 vs P-POSSUM + PML3: 0.91) and 90-day mortality (P-POSSUM:0.79 vs P-POSSUM + PML3: 0.91). PML3 is an accurate predictor of mortality in over-65 s undergoing emergency laparotomy. Addition of PML3 to POSSUM appears to improve mortality risk prediction.
    • Sc3.0: revamping and minimizing the yeast genome

      Dai, Junbiao; email: junbiao.dai@siat.ac.cn; Boeke, Jef D.; Luo, Zhouqing; Jiang, Shuangying; Cai, Yizhi; email: yizhi.cai@manchester.ac.uk (BioMed Central, 2020-08-13)
    • Scalability of resonant motor-driven flapping wing propulsion systems

      Nabawy, Mostafa R. A.; orcid: 0000-0002-4252-1635; email: mostafa.ahmednabawy@manchester.ac.uk; Marcinkeviciute, Ruta (The Royal Society, 2021-09-22)
      This work aims to develop an integrated conceptual design process to assess the scalability and performance of propulsion systems of resonant motor-driven flapping wing vehicles. The developed process allows designers to explore the interaction between electrical, mechanical and aerodynamic domains in a single transparent design environment. Wings are modelled based on a quasi-steady treatment that evaluates aerodynamics from geometry and kinematic information. System mechanics is modelled as a damped second-order dynamic system operating at resonance with nonlinear aerodynamic damping. Motors are modelled using standard equations that relate operational parameters and AC voltage input. Design scaling laws are developed using available data based on current levels of technology. The design method provides insights into the effects of changing core design variables such as the actuator size, actuator mass fraction and pitching kinematics on the overall design solution. It is shown that system efficiency achieves peak values of 30–36% at motor masses of 0.5–1 g when a constant angle of attack kinematics is employed. While sinusoidal angle of attack kinematics demands more aerodynamic and electric powers compared with the constant angle of attack case, sinusoidal angle of attack kinematics can lead to a maximum difference of around 15% in peak system efficiency.
    • Scaling of axial muscle architecture in juvenile Alligator mississippiensis reveals an enhanced performance capacity of accessory breathing mechanisms

      Rose, Kayleigh A. R.; Tickle, Peter G.; Elsey, Ruth M.; Sellers, William I.; orcid: 0000-0002-2913-5406; Crossley, Dane A., II; Codd, Jonathan R.; orcid: 0000-0003-0211-1786; email: jonathan.codd@manchester.ac.uk (2021-07-23)
      Abstract: Quantitative functional anatomy of amniote thoracic and abdominal regions is crucial to understanding constraints on and adaptations for facilitating simultaneous breathing and locomotion. Crocodilians have diverse locomotor modes and variable breathing mechanics facilitated by basal and derived (accessory) muscles. However, the inherent flexibility of these systems is not well studied, and the functional specialisation of the crocodilian trunk is yet to be investigated. Increases in body size and trunk stiffness would be expected to cause a disproportionate increase in muscle force demands and therefore constrain the basal costal aspiration mechanism, necessitating changes in respiratory mechanics. Here, we describe the anatomy of the trunk muscles, their properties that determine muscle performance (mass, length and physiological cross‐sectional area [PCSA]) and investigate their scaling in juvenile Alligator mississippiensis spanning an order of magnitude in body mass (359 g–5.5 kg). Comparatively, the expiratory muscles (transversus abdominis, rectus abdominis, iliocostalis), which compress the trunk, have greater relative PCSA being specialised for greater force‐generating capacity, while the inspiratory muscles (diaphragmaticus, truncocaudalis ischiotruncus, ischiopubis), which create negative internal pressure, have greater relative fascicle lengths, being adapted for greater working range and contraction velocity. Fascicle lengths of the accessory diaphragmaticus scaled with positive allometry in the alligators examined, enhancing contractile capacity, in line with this muscle's ability to modulate both tidal volume and breathing frequency in response to energetic demand during terrestrial locomotion. The iliocostalis, an accessory expiratory muscle, also demonstrated positive allometry in fascicle lengths and mass. All accessory muscles of the infrapubic abdominal wall demonstrated positive allometry in PCSA, which would enhance their force‐generating capacity. Conversely, the basal tetrapod expiratory pump (transversus abdominis) scaled isometrically, which may indicate a decreased reliance on this muscle with ontogeny. Collectively, these findings would support existing anecdotal evidence that crocodilians shift their breathing mechanics as they increase in size. Furthermore, the functional specialisation of the diaphragmaticus and compliance of the body wall in the lumbar region against which it works may contribute to low‐cost breathing in crocodilians.
    • Scholar in the SEPR spotlight: Ian Douglas

      Douglas, Ian; email: ian.douglas@manchester.ac.uk (Springer Singapore, 2020-06-05)
      Abstract: In this reflective essay of intellectual autobiography, I respond to a series of questions the journal editor Wei-Ning Xiang asked about my 55-year journey from applied geography to socio-ecological practice research. These are (1) what and/or who had inspired your career most in geography and socio-ecological practice research? (2) Throughout your 55-year academic journey, did you ever reorient your ambitions in scholarly pursuit, or even reinvent yourself in your academic life? What motivated you in each of these instances? (3) How do you measure success in your work? Among many accomplishments, what are the top three that you are most proud of? (4) From your personal experience, what would be the most important attributes for a well-lived, fully realised, and meaningful life? Do you have any tips for maintaining work-life balance? (5) Do you have any specific advice for younger scholars in geography and socio-ecological practice research? (6) What are the three most interesting images reflecting turning points in your career? I hope that my experiences and insights showcased in this essay are helpful to the younger generations of geographers and socio-ecological practice researchers.
    • Scholar, gentleman and player: a tribute to Eric Dunning

      Malcolm, Dominic; orcid: 0000-0002-5898-2911; Waddington, Ivan; orcid: 0000-0002-5311-9967 (Informa UK Limited, 2020-09-14)
    • Scots pine ( Pinus sylvestris ) dynamics in the Welsh Marches during the mid to late-Holocene

      Sassoon, Dael; orcid: 0000-0003-3992-2320; email: dael.sassoon@manchester.ac.uk; Fletcher, William J; Hotchkiss, Alastair; Owen, Fern; Feng, Liting (SAGE Publications, 2021-02-19)
      Around 4000 cal yr BP, Scots pine (Pinus sylvestris) suffered a widespread demise across the British Isles. This paper presents new information about P. sylvestris populations found in the Welsh Marches (western central Britain), for which the long-term history and origins are poorly known. Two new pollen records were produced from the Lin Can Moss ombrotrophic bog (LM18) and the Breidden Hill pond (BH18). The LM18 peat core is supported by loss-on-ignition, humification analysis and radiocarbon dating. Lead concentrations were used to provide an estimated timeframe for the recent BH18 record. In contrast to many other Holocene pollen records from the British Isles, analysis of LM18 reveals that Scots pine grains were deposited continuously between c. 6900–300 cal yr BP, at frequencies of 0.3–5.4%. It is possible that individual Scots pine trees persisted through the wider demise on thin soils of steep drought-prone crags of hills or the fringes of lowland bogs in the Welsh Marches. At BH18, the record indicates a transition from broadleaved to mixed woodland, including conifer species introduced around AD 1850 including Picea and Pinus. The insights from BH18 suggest that the current populations may largely be the result of planting. Comparison of the LM18 findings with other regional pollen records highlights consistent patterns, including a Mid-Holocene maximum (ca. 7000 cal yr BP), long-term persistence at low pollen percentages and a Late-Holocene minimum (ca. 3000 cal yr BP). These distinctive trends encourage further studies on refugial areas for Scots pine in this region and elsewhere.
    • Screening, Diagnostic and Prognostic Tests for COVID-19: A Comprehensive Review

      Ulinici, Mariana; orcid: 0000-0002-9292-0124; email: mariana.ulinici@usmf.md; Covantev, Serghei; orcid: 0000-0001-7236-5699; email: kovantsev.s.d@gmail.com; Wingfield-Digby, James; email: James.Digby@mft.nhs.uk; Beloukas, Apostolos; orcid: 0000-0001-5639-0528; email: abeloukas@uniwa.gr; Mathioudakis, Alexander G.; orcid: 0000-0002-4675-9616; email: alexander.mathioudakis@manchester.ac.uk; Corlateanu, Alexandru; orcid: 0000-0002-3278-436X; email: alexandru.corlateanu@usmf.md (MDPI, 2021-06-14)
      While molecular testing with real-time polymerase chain reaction (RT-PCR) remains the gold-standard test for COVID-19 diagnosis and screening, more rapid or affordable molecular and antigen testing options have been developed. More affordable, point-of-care antigen testing, despite being less sensitive compared to molecular assays, might be preferable for wider screening initiatives. Simple laboratory, imaging and clinical parameters could facilitate prognostication and triage. This comprehensive review summarises current evidence on the diagnostic, screening and prognostic tests for COVID-19.
    • SDP-Based Robust Formation-Containment Coordination of Swarm Robotic Systems with Input Saturation

      Wu, Kefan; Hu, Junyan; orcid: 0000-0001-7409-3885; email: junyan.hu@manchester.ac.uk; Lennox, Barry; Arvin, Farshad; email: farshad.arvin@manchester.ac.uk (Springer Netherlands, 2021-04-19)
      Abstract: There are many potential applications of swarm robotic systems in real-world scenarios. In this paper, formation-containment controller design for single-integrator and double-integrator swarm robotic systems with input saturation is investigated. The swarm system contains two types of robots—leaders and followers. A novel control protocol and an implementation algorithm are proposed that enable the leaders to achieve the desired formation via semidefinite programming (SDP) techniques. The followers then converge into the convex hull formed by the leaders simultaneously. In contrast to conventional consensus-based formation control methods, the relative formation reference signal is not required in the real-time data transmission, which provides greater feasibility for implementation on hardware platforms. The effectiveness of the proposed formation-containment control algorithm is demonstrated with both numerical simulations and experiments using real robots that utilize the miniature mobile robot, Mona.
    • Seascape genomics reveals population isolation in the reef-building honeycomb worm, Sabellaria alveolata (L.)

      Muir, Anna P.; orcid: 0000-0002-6896-6915; email: a.muir@chester.ac.uk; Dubois, Stanislas F.; Ross, Rebecca E.; Firth, Louise B.; Knights, Antony M.; Lima, Fernando P.; Seabra, Rui; Corre, Erwan; Le Corguillé, Gildas; Nunes, Flavia L. D. (BioMed Central, 2020-08-10)
      Abstract: Background: Under the threat of climate change populations can disperse, acclimatise or evolve in order to avoid fitness loss. In light of this, it is important to understand neutral gene flow patterns as a measure of dispersal potential, but also adaptive genetic variation as a measure of evolutionary potential. In order to assess genetic variation and how this relates to environment in the honeycomb worm (Sabellaria alveolata (L.)), a reef-building polychaete that supports high biodiversity, we carried out RAD sequencing using individuals from along its complete latitudinal range. Patterns of neutral population genetic structure were compared to larval dispersal as predicted by ocean circulation modelling, and outlier analyses and genotype-environment association tests were used to attempt to identify loci under selection in relation to local temperature data. Results: We genotyped 482 filtered SNPs, from 68 individuals across nine sites, 27 of which were identified as outliers using BAYESCAN and ARLEQUIN. All outlier loci were potentially under balancing selection, despite previous evidence of local adaptation in the system. Limited gene flow was observed among reef-sites (FST = 0.28 ± 0.10), in line with the low dispersal potential identified by the larval dispersal models. The North Atlantic reef emerged as a distinct population and this was linked to high local larval retention and the effect of the North Atlantic Current on dispersal. Conclusions: As an isolated population, with limited potential for natural genetic or demographic augmentation from other reefs, the North Atlantic site warrants conservation attention in order to preserve not only this species, but above all the crucial functional ecological roles that are associated with their bioconstructions. Our study highlights the utility of using seascape genomics to identify populations of conservation concern.
    • Seasonal patterns of malaria, genital infection, nutritional and iron status in non-pregnant and pregnant adolescents in Burkina Faso: a secondary analysis of trial data

      Roberts, Stephen A.; orcid: 0000-0002-7477-7731; Brabin, Loretta; orcid: 0000-0003-4478-6503; email: loretta.brabin@manchester.ac.uk; Tinto, Halidou; orcid: 0000-0002-0472-3586; Gies, Sabine; Diallo, Salou; orcid: 0000-0002-1253-4726; Brabin, Bernard; orcid: 0000-0001-6860-2508 (BioMed Central, 2021-09-27)
      Abstract: Background: Adolescents are considered at high risk of developing iron deficiency. Studies in children indicate that the prevalence of iron deficiency increased with malaria transmission, suggesting malaria seasonally may drive iron deficiency. This paper examines monthly seasonal infection patterns of malaria, abnormal vaginal flora, chorioamnionitis, antibiotic and antimalarial prescriptions, in relation to changes in iron biomarkers and nutritional indices in adolescents living in a rural area of Burkina Faso, in order to assess the requirement for seasonal infection control and nutrition interventions. Methods: Data collected between April 2011 and January 2014 were available for an observational seasonal analysis, comprising scheduled visits for 1949 non-pregnant adolescents (≤19 years), (315 of whom subsequently became pregnant), enrolled in a randomised trial of periconceptional iron supplementation. Data from trial arms were combined. Body Iron Stores (BIS) were calculated using an internal regression for ferritin to allow for inflammation. At recruitment 11% had low BIS (< 0 mg/kg). Continuous outcomes were fitted to a mixed-effects linear model with month, age and pregnancy status as fixed effect covariates and woman as a random effect. Dichotomous infection outcomes were fitted with analogous logistic regression models. Results: Seasonal variation in malaria parasitaemia prevalence ranged between 18 and 70% in non-pregnant adolescents (P < 0.001), peaking at 81% in those who became pregnant. Seasonal variation occurred in antibiotic prescription rates (0.7–1.8 prescriptions/100 weekly visits, P < 0.001) and chorioamnionitis prevalence (range 15–68%, P = 0.026). Mucosal vaginal lactoferrin concentration was lower at the end of the wet season (range 2–22 μg/ml, P < 0.016), when chorioamnionitis was least frequent. BIS fluctuated annually by up to 53.2% per year around the mean BIS (5.1 mg/kg2, range 4.1–6.8 mg/kg), with low BIS (< 0 mg/kg) of 8.7% in the dry and 9.8% in the wet seasons (P = 0.36). Median serum transferrin receptor increased during the wet season (P < 0.001). Higher hepcidin concentration in the wet season corresponded with rising malaria prevalence and use of prescriptions, but with no change in BIS. Mean Body Mass Index and Mid-Upper-Arm-Circumference values peaked mid-dry season (both P < 0.001). Conclusions: Our analysis supports preventive treatment of malaria among adolescents 15–19 years to decrease their disease burden, especially asymptomatic malaria. As BIS were adequate in most adolescents despite seasonal malaria, a requirement for programmatic iron supplementation was not substantiated.
    • Seasonal patterns of malaria, genital infection, nutritional and iron status in non-pregnant and pregnant adolescents in Burkina Faso: a secondary analysis of trial data.

      Roberts, Stephen A; orcid: 0000-0002-7477-7731; Brabin, Loretta; orcid: 0000-0003-4478-6503; email: loretta.brabin@manchester.ac.uk; Tinto, Halidou; orcid: 0000-0002-0472-3586; Gies, Sabine; Diallo, Salou; orcid: 0000-0002-1253-4726; Brabin, Bernard; orcid: 0000-0001-6860-2508 (2021-09-27)
      <h4>Background</h4>Adolescents are considered at high risk of developing iron deficiency. Studies in children indicate that the prevalence of iron deficiency increased with malaria transmission, suggesting malaria seasonally may drive iron deficiency. This paper examines monthly seasonal infection patterns of malaria, abnormal vaginal flora, chorioamnionitis, antibiotic and antimalarial prescriptions, in relation to changes in iron biomarkers and nutritional indices in adolescents living in a rural area of Burkina Faso, in order to assess the requirement for seasonal infection control and nutrition interventions.<h4>Methods</h4>Data collected between April 2011 and January 2014 were available for an observational seasonal analysis, comprising scheduled visits for 1949 non-pregnant adolescents (≤19 years), (315 of whom subsequently became pregnant), enrolled in a randomised trial of periconceptional iron supplementation. Data from trial arms were combined. Body Iron Stores (BIS) were calculated using an internal regression for ferritin to allow for inflammation. At recruitment 11% had low BIS (< 0 mg/kg). Continuous outcomes were fitted to a mixed-effects linear model with month, age and pregnancy status as fixed effect covariates and woman as a random effect. Dichotomous infection outcomes were fitted with analogous logistic regression models.<h4>Results</h4>Seasonal variation in malaria parasitaemia prevalence ranged between 18 and 70% in non-pregnant adolescents (P < 0.001), peaking at 81% in those who became pregnant. Seasonal variation occurred in antibiotic prescription rates (0.7-1.8 prescriptions/100 weekly visits, P < 0.001) and chorioamnionitis prevalence (range 15-68%, P = 0.026). Mucosal vaginal lactoferrin concentration was lower at the end of the wet season (range 2-22 μg/ml, P < 0.016), when chorioamnionitis was least frequent. BIS fluctuated annually by up to 53.2% per year around the mean BIS (5.1 mg/kg<sup>2</sup>, range 4.1-6.8 mg/kg), with low BIS (< 0 mg/kg) of 8.7% in the dry and 9.8% in the wet seasons (P = 0.36). Median serum transferrin receptor increased during the wet season (P < 0.001). Higher hepcidin concentration in the wet season corresponded with rising malaria prevalence and use of prescriptions, but with no change in BIS. Mean Body Mass Index and Mid-Upper-Arm-Circumference values peaked mid-dry season (both P < 0.001).<h4>Conclusions</h4>Our analysis supports preventive treatment of malaria among adolescents 15-19 years to decrease their disease burden, especially asymptomatic malaria. As BIS were adequate in most adolescents despite seasonal malaria, a requirement for programmatic iron supplementation was not substantiated.
    • Second-line FOLFOX chemotherapy for advanced biliary tract cancer - Authors' reply.

      Lamarca, Angela; Palmer, Daniel H; Wasan, Harpreet Singh; Ross, Paul J; Ma, Yuk Ting; Arora, Arvind; Falk, Stephen; Gillmore, Roopinder; Wadsley, Jonathan; Patel, Kinnari; et al. (2021-07)
    • Secret Hunger: The Case of Anorexia Nervosa

      Giordano, Simona; orcid: 0000-0002-3608-0263; email: Simona.giordano@manchester.ac.uk (Springer Netherlands, 2020-09-28)
      Abstract: Anorexia nervosa is currently classed as a mental disorder. It is considered as a puzzling condition, scarcely understood and recalcitrant to treatment. This paper reviews the main hypotheses relating to the aetiology of anorexia nervosa. In particular, it focuses on family and sociological studies of anorexia. By reflecting on the hypotheses provided within these domains, and on the questions that these studies leave unanswered, this paper suggests that anorexic behaviour is understandable and rational, if seen in light of ordinary moral values.
    • Secret Hunger: The Case of Anorexia Nervosa

      Giordano, Simona; orcid: 0000-0002-3608-0263; email: Simona.giordano@manchester.ac.uk (Springer Netherlands, 2020-09-28)
      Abstract: Anorexia nervosa is currently classed as a mental disorder. It is considered as a puzzling condition, scarcely understood and recalcitrant to treatment. This paper reviews the main hypotheses relating to the aetiology of anorexia nervosa. In particular, it focuses on family and sociological studies of anorexia. By reflecting on the hypotheses provided within these domains, and on the questions that these studies leave unanswered, this paper suggests that anorexic behaviour is understandable and rational, if seen in light of ordinary moral values.