Probing the relationship between formaldehyde column concentrations and soil moisture using mixed models and attribution analysis

2020 ◽  
Author(s):  
Susanna Strada ◽  
Josep Penuelas ◽  
Marcos Fernández Martinez ◽  
Iolanda Filella ◽  
Ana Maria Yanez-Serrano ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Water Stress ◽  
Drought Index ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Numerical Models ◽  
Positive Trend ◽  
Temperature And Precipitation ◽  
The Impact ◽  
The Relationship

<p align="justify">In response to changes in environmental factors (e.g., temperature, radiation, soil moisture), plants emit biogenic volatile organic compounds (BVOCs). Once released in the atmosphere, BVOCs influence levels of greenhouse gases and air pollutants (e.g., methane, ozone and aerosols), thus affecting both climate and air quality. In turn, climate change may alter BVOC emissions by modifying the driving environmental conditions and by increasing the occurrence and intensity of severe stresses that alter plant functioning. To understand and better constrain the evolution of BVOC emissions under future climates, it is important to reduce the uncertainties in global and regional estimates of BVOC emissions under present climate. Part of the uncertainty in the estimates of BVOC emissions is related to the impact that water stress might have on BVOC emissions. Field campaign, in-situ and laboratory experiments investigated the effect of different regimes of water stress (short- vs. long-term) on BVOC emissions. However, these studies provide geographically scattered and uneven results. To explore the relationship between BVOC emissions and water stress globally, we use remotely sensed soil moisture and formaldehyde, a proxy of BVOC emissions. As BVOCs include a multitude of gas tracers with lifetime ranging from few hours to days, a fully characterisation of these components is virtually impossible. Nevertheless, in the continental boundary layer, formaldehyde is an intermediate by-product of the oxidation of BVOCs, it thus provides a proxy for probing local BVOC emissions, and in particular isoprene, which accounts for about 50% of the total BVOC emissions.</p><p align="justify">In the present study, retrievals of formaldehyde from the Ozone Monitoring Instrument (OMI) are combined with observations of soil moisture, biomass, aerosols, evapotranspiration, drought index, temperature and precipitation. Firstly, we look into the linear annual trend of the selected fields. Secondly, assuming formaldehyde as the dependent variable, we apply a linear mixed model analysis that extends the application of a simple linear regression model by accounting for both fixed (i.e., explained by the independent variables) and random (i.e., due to dependence in the data) effects. The analysis of the linear trend of formaldehyde concentrations shows a positive trend over the Amazon and Central Africa and a negative trend over South Africa and Australia. Over the Amazon, formaldehyde is negatively correlated with the Standardised Precipitation-Evapotranspiration Index (SPEI), a drought index that accounts for both changes in temperature and precipitation, with positive and negative values identifying wet and dry events, respectively. The outcomes of this analysis might provide new insights in the relationship between BVOC emissions and water stress and might help in improving parameterizations that link soil moisture to BVOC emissions in numerical models.</p>

scholarly journals Usefulness of Linear Mixed-Effects Models to Assess the Relationship between Objective and Subjective Internal Load in Team Sports

2021 ◽  
Vol 18 (2) ◽  
pp. 392
Author(s):  
Alice Iannaccone ◽  
Daniele Conte ◽  
Cristina Cortis ◽  
Andrea Fusco
Keyword(s):  
Heart Rate ◽  
Perceived Exertion ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Team Sports ◽  
Rating Of Perceived Exertion ◽  
Subjective Measures ◽  
Internal Load ◽  
Random Slopes ◽  
The Relationship

Internal load can be objectively measured by heart rate-based models, such as Edwards’ summated heart rate zones, or subjectively by session rating of perceived exertion. The relationship between internal loads assessed via heart rate-based models and session rating of perceived exertion is usually studied through simple correlations, although the Linear Mixed Model could represent a more appropriate statistical procedure to deal with intrasubject variability. This study aimed to compare conventional correlations and the Linear Mixed Model to assess the relationships between objective and subjective measures of internal load in team sports. Thirteen male youth beach handball players (15.9 ± 0.3 years) were monitored (14 training sessions; 7 official matches). Correlation coefficients were used to correlate the objective and subjective internal load. The Linear Mixed Model was used to model the relationship between objective and subjective measures of internal load data by considering each player individual response as random effect. Random intercepts were used and then random slopes were added. The likelihood-ratio test was used to compare statistical models. The correlation coefficient for the overall relationship between the objective and subjective internal data was very large (r = 0.74; ρ = 0.78). The Linear Mixed Model using both random slopes and random intercepts better explained (p < 0.001) the relationship between internal load measures. Researchers are encouraged to apply the Linear Mixed Models rather than correlation to analyze internal load relationships in team sports since it allows for the consideration of the individuality of players.

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

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.

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

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 (&gt;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&lt;0.01). Relative to HF, HF+XY improved the AID of GE, CP, and NDF (P&lt;0.05), and improved the ACED, ACOD, and ATTD of DM, GE, CP, NDF, ADF, and hemicellulose (P&lt;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&lt;0.01). Pigs fed xylanase had a greater proportion of acetate in cecal digesta and butyrate in colonic digesta among treatments (P&lt;0.05). Compared with LF, HF increased ileal, cecal, and colonic viscosity, but HF+XY decreased ileal viscosity compared with HF (P&lt;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.

Size-related boldness is not altered by stomach flushing in a terrestrial salamander

2021 ◽  
pp. 1-6
Author(s):  
Sebastiano Salvidio ◽  
Andrea Costa ◽  
Fabrizio Oneto
Keyword(s):  
Body Condition ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Animal Personality ◽  
Model Analysis ◽  
Mixed Model Analysis ◽  
Linear Mixed Model Analysis ◽  
Before And After ◽  
Trophic Strategy ◽  
The Relationship

Abstract Animal personality is a relatively neglected field in amphibian research. In this study we assessed the influence of stomach flushing, a non-lethal technique used in amphibian dietary studies, on the boldness behaviour of the cave salamander Speleomantes strinatii. The time of emergence from a shelter located in an unfamiliar environment (a proxy for individual boldness) was measured in 26 cave salamanders before and after stomach flushing, while 14 non-flushed salamanders were tested as controls. Boldness was a repeatable behaviour for salamanders and larger individuals emerged from their shelter more rapidly than smaller ones. Linear mixed model analysis showed that flushing, sex and body condition had no effect on this behaviour. These findings are promising in the framework of the study of salamander personality. In particular, our results will be useful when exploring the relationship between individual trophic strategy and boldness, aggression or exploration behaviours in terrestrial salamanders.

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

2018 ◽  
Vol 147 ◽  
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.

scholarly journals 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

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
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.

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

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 &lt;10km from a wind farm and self-reporting sleep disturbance; 19 living &lt;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 &gt;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.

scholarly journals THE IMPACT OF HOSPITAL BASED INTEGRATED MANAGEMENT OF CHILDHOOD ILLNESS TRAINING ON PEDIATRIC NURSE COMPETENCY

2018 ◽  
Vol 4 (1) ◽  
pp. 16-23
Author(s):  
Fitri Haryanti ◽  
Mohammad Hakimi ◽  
Yati Sunarto ◽  
Yayi S Prabandari
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Integrated Management ◽  
Well Being ◽  
Childhood Illness ◽  
Internal Conflict ◽  
Child Health Services ◽  
Management Support ◽  
The Impact

Background: Although the WHO strategy integrated management of childhood illness (IMCI) for primary care has been implemented in over 100 countries, there is less global experience with hospital-based IMCI training. Until recently, no training had been done in Indonesia, and globally there has been limited experience of the role of IMCI in rebuilding health systems after complex emergencies.Objective: We aimed to examine the effect of hospital-based IMCI training on pedicatric nurse competency and explore the perception of Indonesian doctors, nurse managers and paediatricians about IMCI training and its development in West Aceh, a region that was severely affected by the South-Asian tsunami in December 2004.Methods: This study used stepped wedge design. Training was conducted for 39 nurses staff, 13 midwifes, 6 Head nurses, 5 manager of nurses, 5 doctors, 1 paediatricians, and 3 support facilities  (nutritionist, pharmacist, laboratory) in Cut Nyak Dien (CND) Hospital in Meulaboh, West Aceh, Indonesia. The IMCI training was developed based on the WHO Pocketbook of Hospital Care for Children. A nurses competency questionnaire was used based on the guideline of assessment of the quality of child health services at the first level reference hospitals in districts / municipalities issued by the Ministry of Health in 2007. A linear mixed model was used for data analysis.Results: The hospital based IMCI training improved the competences of nurses paediatric in assessing emergency signs of the sick children, management of cough and difficulty breathing, diarrhoea, fever, nutritional problems, supportive care, monitoring, discharge planning and follow up.  The assessment highlighted several problems in adaptation process of material training, training process and implementation in an environment soon after a major disaster.Conclusion: Hospital based IMCI training can be implemented in a setting after major disasters or internal conflict as part of a rebuilding process.  The program requires strong management support and the emergency phase to be subsided.  Other pre-requisites include the existence of standard operating procedures, adequate physical facilities and support for staff morale and well-being.  Improving the quality of paediatric care requires more than just training and clinical guidelines; internal motivation and health worker support are essential.

scholarly journals Thalamic white matter macrostructure and subnuclei volumes in Parkinson’s disease depression

2022 ◽  
Vol 8 (1) ◽  
Author(s):  
R. Bhome ◽  
A. Zarkali ◽  
G. E. C. Thomas ◽  
J. E. Iglesias ◽  
J. H. Cole ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
White Matter ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Neural Structure ◽  
Generalised Linear Mixed Model ◽  
Antidepressant Use ◽  
The Relationship

AbstractDepression is a common non-motor feature of Parkinson’s disease (PD) which confers significant morbidity and is challenging to treat. The thalamus is a key component in the basal ganglia-thalamocortical network critical to the pathogenesis of PD and depression but the precise thalamic subnuclei involved in PD depression have not been identified. We performed structural and diffusion-weighted imaging (DWI) on 76 participants with PD to evaluate the relationship between PD depression and grey and white matter thalamic subnuclear changes. We used a thalamic segmentation method to divide the thalamus into its 50 constituent subnuclei (25 each hemisphere). Fixel-based analysis was used to calculate mean fibre cross-section (FC) for white matter tracts connected to each subnucleus. We assessed volume and FC at baseline and 14–20 months follow-up. A generalised linear mixed model was used to evaluate the relationship between depression, subnuclei volume and mean FC for each thalamic subnucleus. We found that depression scores in PD were associated with lower right pulvinar anterior (PuA) subnucleus volume. Antidepressant use was associated with higher right PuA volume suggesting a possible protective effect of treatment. After follow-up, depression scores were associated with reduced white matter tract macrostructure across almost all tracts connected to thalamic subnuclei. In conclusion, our work implicates the right PuA as a relevant neural structure in PD depression and future work should evaluate its potential as a therapeutic target for PD depression.

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

2021 ◽  
Author(s):  
David J Pascall ◽  
Guy Mollett ◽  
Rachel Blacow ◽  
Naomi Bulteel ◽  
Robyn Campbell ◽  
...  
Keyword(s):  
Growth Rate ◽  
Cohort Study ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Transmission Rate ◽  
Severe Disease ◽  
Positive Association ◽  
Clinical Severity ◽  
Generalised Linear Mixed Model ◽  
The Impact

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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