The SARS-CoV-2 Alpha variant is associated with increased clinical severity of disease

Background The Alpha (B.1.1.7) SARS-CoV-2 variant of concern has been associated with increased transmission and increased 28-day mortality. We aimed to investigate the impact of infection on clinical severity of illness, including the need for oxygen or ventilation in a national cohort study. Methods In this prospective clinical cohort study, 1475 SARS-CoV-2 sequences were obtained from patients infected in Scotland, UK between the 1st November 2020 and 30th January 2021 and matched to clinical outcomes as the lineage became dominant in Scotland. We modelled the association between B.1.1.7 infection and severe disease using a cumulative generalised linear mixed model employing a 4-point scale of maximum severity based on requirement of respiratory support at 28 days. We also estimated the growth rate of B.1.1.7-associated infections as it emerged in Scotland using a phylogenetic exponential growth rate population model. Results The B.1.1.7 lineage was responsible for a third wave of SARS-CoV-2 infection in Scotland in association with a transmission rate 5-fold higher than the preceding second wave B.1.177 lineage. Of 1475 patients, 364 were infected with B.1.1.7, 1030 with B.1.177 and 81 with other lineages. Our analysis found a positive association between increased clinical severity and lineage (B.1.1.7 versus non-B.1.1.7; cumulative odds ratio: 1.40, 95% CI: 1.02, 1.93). Viral load was higher in B.1.1.7 samples than in non-B.1.1.7 samples, as measured by cycle threshold (Ct) value (mean Ct change: -2.46, 95% CI: -4.22, -0.70). Conclusions The B.1.1.7 lineage was associated with more severe clinical disease in Scottish patients than co-circulating lineages.

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Predictors of virus prevalence and diversity across a wild bumblebee community

10.1101/2021.01.06.425554 ◽

2021 ◽

Author(s):

David J. Pascall ◽

Matthew C. Tinsley ◽

Bethany L. Clark ◽

Darren J. Obbard ◽

Lena Wilfert

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Natural Populations ◽

Ecological Factors ◽

Positive Association ◽

Population Declines ◽

Fitness Effects ◽

Wild Host ◽

Generalised Linear Mixed Model ◽

Paralysis Virus

AbstractViruses are a key regulator of natural populations. Despite this, we have limited knowledge of the diversity and ecology of viruses that lack obvious fitness effects on their host. This is even the case in wild host populations that provide ecosystem services, where small fitness effects may have major ecological and financial impacts in aggregate. One such group of hosts are the bumblebees, which have a major role in the pollination of food crops and have suffered population declines and range contractions in recent decades. In this study, we used a multivariate generalised linear mixed model to investigate the ecological factors that determine the prevalence of four recently discovered bumblebee viruses (Mayfield virus 1, Mayfield virus 2, River Liunaeg virus and Loch Morlich virus), and two previously known viruses that infect both wild bumblebees and managed honeybees (Acute bee paralysis virus and Slow bee paralysis virus). We show that the recently discovered bumblebee viruses were more genetically diverse than the viruses shared with honeybees, potentially due to spillover dynamics of shared viruses. We found evidence for ecological drivers of prevalence in our samples, with relatively weak evidence for a positive effect of precipitation on the prevalence of River Luinaeg virus. Coinfection is potentially important in shaping prevalence: we found a strong positive association between River Liunaeg virus and Loch Morlich virus presence after controlling for host species, location and other relevant ecological variables. This study represents a first step in the description of predictors of bumblebee infection in the wild not driven by spillover from honeybees.

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Physiological stress response of African elephants to wildlife tourism in Madikwe Game Reserve, South Africa

Wildlife Research ◽

10.1071/wr19045 ◽

2020 ◽

Vol 47 (1) ◽

pp. 34 ◽

Cited By ~ 4

Author(s):

Isabelle D. Szott ◽

Yolanda Pretorius ◽

Andre Ganswindt ◽

Nicola F. Koyama

Keyword(s):

South Africa ◽

Mixed Model ◽

Linear Mixed Model ◽

Physiological Stress ◽

Traumatic Experiences ◽

African Elephants ◽

Conservation Action ◽

Generalised Linear Mixed Model ◽

Game Reserve ◽

The Impact

Abstract ContextWildlife tourism has been shown to increase stress in a variety of species and can negatively affect survival, reproduction, welfare, and behaviour of individuals. In African elephants, Loxodonta africana, increased physiological stress has been linked to use of refugia, rapid movement through corridors, and heightened aggression towards humans. However, we are unaware of any studies assessing the impact of tourism pressure (tourist numbers) on physiological stress in elephants. AimsWe used faecal glucocorticoid metabolite (fGCM) concentrations to investigate whether tourist numbers in Madikwe Game Reserve, South Africa, were related to changes in physiological stress in elephants. MethodsWe repeatedly collected dung samples (n=43) from 13 individually identified elephants over 15 months. Using a generalised linear mixed model and a Kenward–Roger approximation, we assessed the impact of monthly tourist numbers, season, age, and sex on elephant fGCM concentrations. Key resultsHigh tourist numbers were significantly related to elevated fGCM concentrations. Overall, fGCM concentrations increased by 112% (from 0.26 to 0.55µgg−1 dry weight) in the months with the highest tourist pressure, compared to months with the lowest tourist pressure. ConclusionsManagers of fenced reserves should consider providing potential alleviation measures for elephants during high tourist pressure, for example, by ensuring that refuge areas are available. This may be of even higher importance if elephant populations have had traumatic experiences with humans in the past, such as poaching or translocation. Such management action will improve elephant welfare and increase tourist safety. ImplicationsAlthough tourism can generate substantial revenue to support conservation action, careful monitoring of its impact on wildlife is required to manage potential negative effects.

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The Impact of Biographical Information About a Composer on Emotional Responses to Their Music

Musicae Scientiae ◽

10.1177/1029864920988883 ◽

2021 ◽

pp. 102986492098888

Author(s):

Frederic Kiernan ◽

Amanda E. Krause ◽

Jane W. Davidson

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Emotional Responses ◽

Predictor Variable ◽

Free Text ◽

Chi Square ◽

Biographical Information ◽

Generalised Linear Mixed Model ◽

Chi Square Test ◽

The Impact

This study investigated whether reading biographical information about the composer Jan Dismas Zelenka (1679–1745) before listening to his music would influence listeners’ self-reported emotional responses. The study involved 179 participants who completed an online listening exercise in which they read either a negative or a neutral biography of Zelenka, or no biography, before listening to two short excerpts of his music. After listening to each excerpt, participants completed a 27-item questionnaire concerning their emotional responses and were then asked to describe in their own words how the music made them feel. Two-factor analyses identified five factors underlying the emotional responses of participants for each musical excerpt. Generalised Linear Mixed Model analyses indicate that the biography condition affected participants’ emotional responses with regard to memories, associations, and mental images. Positive emotional contagion was also a significant predictor variable for several of the emotional factors that were identified. A thematic analysis of participants’ free-text responses supported both the BRECVEMAC model and persona theory as interpretative frameworks, albeit with caveats. Additionally, a chi-square test of contingencies revealed that participants who read the negative biography of Zelenka were more likely to make use of negative language to describe their emotional responses to the music, and that participants who read no biography were more likely to use neutral language. The findings suggest that contextual biographical information about composers (e.g., in programme notes) can have an impact on the emotional experiences of listeners.

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103 Periodontal Health and Sarcopenia: Cross-Sectional Evidence From A Cohort of 2040 Twin Volunteers

Age and Ageing ◽

10.1093/ageing/afab030.64 ◽

2021 ◽

Vol 50 (Supplement_1) ◽

pp. i12-i42

Author(s):

M B Zazzara ◽

P M Wells ◽

R C E Bowyer ◽

M N Lochlainn ◽

E J Thompson ◽

...

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Frailty Index ◽

Muscle Quality ◽

Low Grade ◽

Periodontal Health ◽

Cross Sectional ◽

Age Related ◽

European Working ◽

Generalised Linear Mixed Model

Abstract Introduction Periodontitis is a chronic inflammatory disease affecting the periodontium, ultimately leading to looseness and/or loss of teeth. Sarcopenia refers to age-related reduction in muscle mass and strength. Similar to periodontitis, chronic low-grade inflammation is thought to play a key role in its development. In addition, both increase in prevalence with advancing age. Despite known associations with other diseases involving a dysregulated inflammatory response, for example rheumatoid arthritis,, the relationship between periodontitis and sarcopenia, and whether they could be driven by similar processes, remains uncertain. The aim of this study was to explore the association between periodontitis and sarcopenia. Methods Observational study of 2040 adult volunteers [age 67.18 (12.17)] enrolled in the TwinsUK cohort study. Presence of tooth mobility and number of teeth lost were used to assess periodontal health. A binary variable was created to define periodontitis. Measurements of muscle strength, muscle quality/quantity and physical performance were used to assess sarcopenia. A categorical variable was created according to the European Working Group on Sarcopenia in Older People (EWGSOP2) consensus, to define sarcopenia (1: probable; 2: positive; 3: severe). Generalised linear mixed model analysis used on complete cases and age-matched (n = 1,288) samples to ascertain associations between periodontitis and sarcopenia. Results No significant association was found between periodontitis and sarcopenia in both the complete cases analysis and age-matched analysis. Results were consistent when analysis was adjusted for potential confounders including body mass index, frailty index, Mini Mental State Examination smoking, nutritional status and educational level. Conclusions This study found no significant association between periodontitis and sarcopenia in a cohort of 2040 adults. Although both periodontitis and sarcopenia have been linked to a dysregulated immune response and demonstrate an increase in prevalence with increasing age, our work is inconclusive due to the plethora of possible aetiopathogenetic pathways.

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Clinical implementation of a 3D4K-exoscope (Orbeye) in microneurosurgery

Neurosurgical Review ◽

10.1007/s10143-021-01577-3 ◽

2021 ◽

Author(s):

Judith Rösler ◽

Stefan Georgiev ◽

Anna L. Roethe ◽

Denny Chakkalakal ◽

Güliz Acker ◽

...

Keyword(s):

User Satisfaction ◽

Mixed Model ◽

Linear Mixed Model ◽

Intraoperative Complications ◽

Rank Test ◽

User Group ◽

Clinical Implementation ◽

Physical Strain ◽

Conventional Microscope ◽

The Impact

AbstractExoscopic surgery promises alleviation of physical strain, improved intraoperative visualization and facilitation of the clinical workflow. In this prospective observational study, we investigate the clinical usability of a novel 3D4K-exoscope in routine neurosurgical interventions. Questionnaires on the use of the exoscope were carried out. Exemplary cases were additionally video-documented. All participating neurosurgeons (n = 10) received initial device training. Changing to a conventional microscope was possible at all times. A linear mixed model was used to analyse the impact of time on the switchover rate. For further analysis, we dichotomized the surgeons in a frequent (n = 1) and an infrequent (n = 9) user group. A one-sample Wilcoxon signed rank test was used to evaluate, if the number of surgeries differed between the two groups. Thirty-nine operations were included. No intraoperative complications occurred. In 69.2% of the procedures, the surgeon switched to the conventional microscope. While during the first half of the study the conversion rate was 90%, it decreased to 52.6% in the second half (p = 0.003). The number of interventions between the frequent and the infrequent user group differed significantly (p = 0.007). Main reasons for switching to ocular-based surgery were impaired hand–eye coordination and poor depth perception. The exoscope investigated in this study can be easily integrated in established neurosurgical workflows. Surgical ergonomics improved compared to standard microsurgical setups. Excellent image quality and precise control of the camera added to overall user satisfaction. For experienced surgeons, the incentive to switch from ocular-based to exoscopic surgery greatly varies.

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The influence of xylanase on the fermentability, digestibility, and physiochemical properties of insoluble corn-based fiber along the gastrointestinal tract of growing pigs

Journal of Animal Science ◽

10.1093/jas/skab159 ◽

2021 ◽

Author(s):

Amy L Petry ◽

Nichole F Huntley ◽

Michael R Bedford ◽

John F Patience

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Nutrient Digestibility ◽

Growing Pigs ◽

Neutral Detergent Fiber ◽

Adaptation Period ◽

High Fiber ◽

Gross Energy ◽

Digesta Viscosity ◽

The Impact

Abstract In theory, supplementing xylanase in corn-based swine diets should improve nutrient and energy digestibility and fiber fermentability, but its efficacy is inconsistent. The experimental objective was to investigate the impact of xylanase on energy and nutrient digestibility, digesta viscosity, and fermentation when pigs are fed a diet high in insoluble fiber (>20% neutral detergent fiber; NDF) and given a 46-d dietary adaptation period. Three replicates of 20 growing gilts were blocked by initial body weight, individually housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF) with 7.5% NDF, a 30% corn bran high-fiber control (HF; 21.9% NDF), HF+100 mg xylanase/kg [HF+XY, (Econase XT 25P; AB Vista, Marlborough, UK)] providing 16,000 birch xylan units/kg; and HF+50 mg arabinoxylan-oligosaccharide (AXOS) product/kg [HF+AX, (XOS 35A; Shandong Longlive Biotechnology, Shandong, China)] providing AXOS with 3-7 degrees of polymerization. Gilts were allowed ad libitum access to fed for 36-d. On d 36, pigs were housed in metabolism crates for a 10-d period, limit fed, and feces were collected. On d 46, pigs were euthanized and ileal, cecal, and colonic digesta were collected. Data were analyzed as a linear mixed model with block and replication as random effects, and treatment as a fixed effect. Compared with LF, HF reduced the apparent ileal digestibility (AID), apparent cecal digestibility (ACED), apparent colonic digestibility (ACOD), and apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), crude protein (CP), acid detergent fiber (ADF), NDF, and hemicellulose (P<0.01). Relative to HF, HF+XY improved the AID of GE, CP, and NDF (P<0.05), and improved the ACED, ACOD, and ATTD of DM, GE, CP, NDF, ADF, and hemicellulose (P<0.05). Among treatments, pigs fed HF had increased hindgut DM disappearance (P=0.031). Relative to HF, HF+XY improved cecal disappearance of DM (162 vs. 98g; P=0.008) and NDF (44 vs. 13g; P<0.01). Pigs fed xylanase had a greater proportion of acetate in cecal digesta and butyrate in colonic digesta among treatments (P<0.05). Compared with LF, HF increased ileal, cecal, and colonic viscosity, but HF+XY decreased ileal viscosity compared with HF (P<0.001). In conclusion, increased insoluble corn-based fiber decreases digestibility, reduces cecal fermentation, and increases digesta viscosity, but supplementing xylanase partially mitigated that effect.

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Factors influencing the occurrence of high ultimate pH in three muscles of lamb carcasses in Australia

Animal Production Science ◽

10.1071/an14315 ◽

2014 ◽

Vol 54 (10) ◽

pp. 1853 ◽

Cited By ~ 8

Author(s):

N. G. McPhail ◽

J. L. Stark ◽

A. J. Ball ◽

R. D. Warner

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Rectus Femoris ◽

Carcass Weight ◽

Mixed Model Analysis ◽

Factors Influencing ◽

South Wales ◽

Generalised Linear Mixed Model ◽

Processing Plants ◽

Few Data

Chilled lamb meat exported from Australia has, on occasions, been rejected by importing countries due to greening, after only 6 weeks of storage time. Greening is known to be more prevalent in high ultimate pH (pHu) beef meat (>5.9). There are few data available for lamb carcasses in Australia on the occurrence of high pHu meat, which may have an impact on the understanding and control of quality and greening during storage. The aim of this project was to determine the prevalence of, and influencing factors for, high pHu meat in a range of muscle types in lamb carcasses in Australia. Muscle pHu data were collected from a total of 1614 carcasses from 78 lots at four lamb processing plants in Victoria and New South Wales in autumn and spring of 2013. The pHu of the knuckle (rectus femoris), rack (longissimus) and blade (infraspinatus) was measured and data on carcass and lot characteristics were recorded. Data were subjected to restricted maximum likelihood and generalised linear mixed model analysis. The mean pHu of the knuckle, rack and shoulder were 6.06, 5.79 and 6.12 respectively, and the main factors influencing muscle pHu and occurrence of dark-cutting were breed, season, electrical stimulation and carcass weight. Merino lambs had a higher pHu in the blade and knuckle than did other breeds (P < 0.05, P < 0.01 respectively). Lambs processed in autumn had a higher predicted pHu in the blade and knuckle and a higher percentage dark-cutting (DC; pHu >6.0) for those muscles, than did those processed in spring (P < 0.05). Carcasses that had been electrically stimulated had a higher %DC and a higher pHu in all three muscles (P < 0.05). Carcass weight had a significant effect on the pHu of all three muscles (P < 0.001), with heavier carcasses having a lower pHu and lower %DC. The pHu of the rack was not a reliable predictor for the pHu in other muscles of the lamb carcass. In conclusion, the high occurrence of DC in the muscles, particularly the blade and knuckle, suggests that these muscles may be at risk for producing greening in the vacuum bag during storage.

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Bayesian spatial and spatio-temporal approaches to modelling dengue fever: a systematic review

Epidemiology and Infection ◽

10.1017/s0950268818002807 ◽

2018 ◽

Vol 147 ◽

Cited By ~ 8

Author(s):

A. Aswi ◽

S. M. Cramb ◽

P. Moraga ◽

K. Mengersen

Keyword(s):

Dengue Fever ◽

Random Effects ◽

Mixed Model ◽

Linear Mixed Model ◽

Assessment Tool ◽

Temporal Dynamics ◽

Random Effect ◽

Temperature And Precipitation ◽

Generalised Linear Mixed Model ◽

Spatio Temporal

AbstractDengue fever (DF) is one of the world's most disabling mosquito-borne diseases, with a variety of approaches available to model its spatial and temporal dynamics. This paper aims to identify and compare the different spatial and spatio-temporal Bayesian modelling methods that have been applied to DF and examine influential covariates that have been reportedly associated with the risk of DF. A systematic search was performed in December 2017, using Web of Science, Scopus, ScienceDirect, PubMed, ProQuest and Medline (via Ebscohost) electronic databases. The search was restricted to refereed journal articles published in English from January 2000 to November 2017. Thirty-one articles met the inclusion criteria. Using a modified quality assessment tool, the median quality score across studies was 14/16. The most popular Bayesian statistical approach to dengue modelling was a generalised linear mixed model with spatial random effects described by a conditional autoregressive prior. A limited number of studies included spatio-temporal random effects. Temperature and precipitation were shown to often influence the risk of dengue. Developing spatio-temporal random-effect models, considering other priors, using a dataset that covers an extended time period, and investigating other covariates would help to better understand and control DF transmission.

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The Use of Telehealth Technology in Assessing the Accuracy of Self-Reported Weight and the Impact of a Daily Immediate-Feedback Intervention among Obese Employees

International Journal of Telemedicine and Applications ◽

10.1155/2011/909248 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Nicolaas P. Pronk ◽

A. Lauren Crain ◽

Jeffrey J. VanWormer ◽

Brian C. Martinson ◽

Jackie L. Boucher ◽

...

Keyword(s):

Body Weight ◽

Mixed Model ◽

Linear Mixed Model ◽

Controlled Trial ◽

Intervention Group ◽

Study Groups ◽

Outcome Variable ◽

Control Group ◽

Immediate Feedback ◽

The Impact

Objective.To determine the accuracy of self-reported body weight prior to and following a weight loss intervention including daily self-weighing among obese employees.Methods.As part of a 6-month randomized controlled trial including a no-treatment control group, an intervention group received a series of coaching calls, daily self-weighing, and interactive telemonitoring. The primary outcome variable was the absolute discrepancy between self-reported and measured body weight at baseline and at 6 months. We used general linear mixed model regression to estimate changes and differences between study groups over time.Results.At baseline, study participants underreported their weight by an average of 2.06 (se=0.33) lbs. The intervention group self-reported a smaller absolute body weight discrepancy at followup than the control group.Conclusions.The discrepancy between self-reported and measured body weight appears to be relatively small, may be improved through daily self-monitoring using immediate-feedback telehealth technology, and negligibly impacts change in body weight.

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O003 The impact of wind farm noise in a laboratory setting on objective and subjective sleep efficiency

SLEEP Advances ◽

10.1093/sleepadvances/zpab014.002 ◽

2021 ◽

Vol 2 (Supplement_1) ◽

pp. A1-A2

Author(s):

T Liebich ◽

L Lack ◽

G Micic ◽

K Hansen ◽

B Zajamsek ◽

...

Keyword(s):

Sleep Disturbance ◽

Wind Farm ◽

Mixed Model ◽

Linear Mixed Model ◽

Sleep Efficiency ◽

Self Report ◽

Sleep Diary ◽

Noise Condition ◽

Subjective Sleep ◽

The Impact

Abstract Introduction Well-controlled studies of wind farm noise (WFN) on sleep are lacking despite complaints and known effects of other noise types on sleep. This laboratory-based study investigated the impact of continuous full-night WFN exposure replicated from field recordings on polysomnography-measured (objective) and sleep diary-determined (subjective) sleep efficiency compared to a quiet control night. Methods Based on residential location and self-report data, 50 participants were categorised into three groups (14 living <10km from a wind farm and self-reporting sleep disturbance; 19 living <10km from a wind farm and self-reporting no sleep disturbance and 18 controls living in a quiet rural area). Participants underwent full in-laboratory polysomnography during exposure to continuous WFN (25 dB(A)) throughout the night and a quiet control night (background noise 19 dB(A)) in random order. Group and noise condition effects were examined via linear mixed model analysis. Results Participants (30 females) were aged (mean±SD) 54.9±17.6 range: 18–80 years. Sleep efficiency in the control condition was (median [interquartile range]) objective: 85.5 [77.4 to 91.2]%; subjective: 85.7 [69.2 to 92.7]%) versus the WFN condition (objective: 86.1 [78.6 to 91.7]% subjective: 85.8 [66.2 to 93.8]%) with no significant main or interaction effects of group or noise condition (all p’s >0.05). Conclusion These results do not support that WFN at 25 dB(A) significantly impacts objective or subjective sleep efficiency in participants with or without prior WFN exposure or self-reported WFN-related sleep disturbance. Further analyses to investigate potential sleep micro-structural changes remain warranted.

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