Tag: pubmed

Evolution. 2022 Mar 27. doi: 10.1111/evo.14486. Online ahead of print.

ABSTRACT

Log-linear models are widely used for assessing determinants of fitness in empirical studies, for example, in determining how reproductive output depends on trait values or environmental conditions. Similarly, theoretical works of fitness and natural selection employ log-linear models, often with a negative quadratic term, generating Gaussian fitness functions. However, in the specific application of regression-based analysis of natural selection, such models are rarely employed. Rather, OLS regression is the predominant means of assessing the form of natural selection. OLS regressions allow specific evolutionary quantitative parameters, selection gradients, to be estimated, and benefit from the fact that the associated statistical models are easily applied. We examine whether selection gradients can be directly expressed in terms of the coefficients of models using exponential fitness functions with linear or quadratic arguments. Such models can be easily fitted with generalised linear models (GLMs). The expressions we obtain coincide with those for Gaussian functions, but relax the major constraint that the (log) fitness function is concave (downwardly curved). Additionally these results lead to univariate and multivariate analyses of both linear and quadratic selection that potentially incorporate pragmatic and interpretable models of fitness functions, where the parameters can be related analytically to selection gradients, and that can be operationalised using widely-available statistical tools. This article is protected by copyright. All rights reserved.

PMID:35340021 | DOI:10.1111/evo.14486

Gait Posture. 2022 Mar 21;94:166-172. doi: 10.1016/j.gaitpost.2022.03.012. Online ahead of print.

ABSTRACT

BACKGROUND: Limited attention has been paid to age- or body size-related changes in the ground reaction forces (GRF) during walking despite their strong associations with lower limb injuries and pathology.

RESEARCH QUESTION: Do the features of GRF during walking associate with age or body size?

METHODS: Fifty-four participants were subdivided into four groups according to their age and body size: overweight old (n = 12), non-overweight old (n = 13), overweight young (n = 13), and non-overweight young (n = 16). Participants were asked to walk at their self-selected speeds on level ground with force plates embedded in the center of walkway. Functional principal component analysis (FPCA) was performed to extract major modes of variation and functional principal component scores (FPCs) in three-dimensional GRFs. Analysis of variance models were employed to investigate the effect of age, body size, or their interactions on the FPCs of each component of the GRF, with the adjustment to gait speed.

RESULTS: Significant age and body size effects were observed in FPC1 across all three-dimensional GRF. Both overweight and older groups showed greater braking force after heel-strike and greater propulsive forces during pre-swing when compared to the non-overweight and younger groups, respectively. The overweight old group displayed greater medial forces during mid-stance and the overweight young group showed prominently larger medial forces during pre-swing, while non-overweight old showed a tendency of flatter medial-lateral GRF waveforms during the entire stance phase. FPC2 revealed that only body size had an effect on three-dimensional GRF with the highest FPC2 scores in the overweight old group.

SIGNIFICANCE: Three-dimensional GRF during walking could be altered by the body size and age, which were more pronounced in the overweight and older group. The more dynamic GRF pattern with greater and/or lower peaks could be contributing factors to the increased joint load and injury rates observed in overweight aged individuals.

PMID:35339964 | DOI:10.1016/j.gaitpost.2022.03.012

Med Image Anal. 2022 Mar 17;78:102422. doi: 10.1016/j.media.2022.102422. Online ahead of print.

ABSTRACT

Multiphase CT scanning of the liver is performed for several clinical applications; however, radiation exposure from CT scanning poses a nontrivial cancer risk to the patients. The radiation dose may be reduced by determining the scan range of the subsequent scans by the location of the target of interest in the first scan phase. The purpose of this study is to present and assess an automatic method for determining the scan range for multiphase CT scans. Our strategy is to first apply a CNN-based method for detecting the liver in 2D slices, and to use a liver range search algorithm for detecting the liver range in the scout volume. The target liver scan range for subsequent scans can be obtained by adding safety margins achieved from Gaussian liver motion models to the scan range determined from the scout. Experiments were performed on 657 multiphase CT volumes obtained from multiple hospitals. The experiment shows that the proposed liver detection method can detect the liver in 223 out of a total of 224 3D volumes on average within one second, with mean intersection of union, wall distance and centroid distance of 85.5%, 5.7 mm and 9.7 mm, respectively. In addition, the performance of the proposed liver detection method is comparable to the best of the state-of-the-art 3D liver detectors in the liver detection accuracy while it requires less processing time. Furthermore, we apply the liver scan range generation method on the liver CT images acquired from radiofrequency ablation and Y-90 transarterial radioembolization (selective internal radiation therapy) interventions of 46 patients from two hospitals. The result shows that the automatic scan range generation can significantly reduce the effective radiation dose by an average of 14.5% (2.56 mSv) compared to manual performance by the radiographer from Y-90 transarterial radioembolization, while no statistically significant difference in performance was found with the CT images from intra RFA intervention (p = 0.81). Finally, three radiologists assess both the original and the range-reduced images for evaluating the effect of the range reduction method on their clinical decisions. We conclude that the automatic liver scan range generation method is able to reduce excess radiation compared to the manual performance with a high accuracy and without penalizing the clinical decision.

PMID:35339951 | DOI:10.1016/j.media.2022.102422

Health Place. 2022 Mar 24;75:102778. doi: 10.1016/j.healthplace.2022.102778. Online ahead of print.

ABSTRACT

There has been a generally negative view of the impact of urbanization on a rising burden of non-communicable diseases including cardiovascular disease. However, the evidence on the relationship between urbanization and cardiovascular health has remained inconclusive. A comprehensive picture of the relationship is lacking, given an implicit assumption that the longitudinal association between changes in cardiovascular health and an increasingly urbanized environment is similar between less and more urbanized communities, men and women. We used the longitudinal data on adults (18-64 years) from the China Health and Nutrition Survey (1991-2015) and employed within-between random-effects models to disaggregates the longitudinal and cross-sectional associations between urbanization and systolic/diastolic blood pressure (SBP/DBP) and examined heterogeneities in the longitudinal association by average urbanization level and gender. We found that the positive longitudinal association of urbanization with SBP/DBP was stronger in less urbanized than more urbanized communities. The cross-sectional association between urbanization and SBP was negative and significant, although the cross-sectional association between urbanization and DBP was of no statistical significance. Moreover, the positive longitudinal association between urbanization and DBP was stronger among men than women, although the gender heterogeneity in the longitudinal association of urbanization with SBP was not significant.

PMID:35339955 | DOI:10.1016/j.healthplace.2022.102778

Poult Sci. 2022 Feb 22;101(5):101798. doi: 10.1016/j.psj.2022.101798. Online ahead of print.

ABSTRACT

Dermanyssus gallinae is an obligatory ectoparasite of birds which feeds on blood and significantly compromise the well-being of commercially raised laying hens. In this study, the mortality rates and responses of D. gallinae to 2 acaricides with a physical mode of action (Dergall and Mite Max) and 2 acaricides with a chemical mode of action (Milben Ex and Bio PK) were evaluated in tree dilutions (S1-3) and compared at 8-time intervals after application. The evaluation involved a novel method that simulates real-world conditions in a commercial poultry farm. Tested products have shown high efficacy (84.3-100%) against D. gallinae in the producer recommended solution (S1). Acaricides with a physical mechanism of action were as effective as chemical agents in eradicating poultry red mites. The compared preparations differed only in the onset of action which was longer in acaricides with a physical mode of action (1-6 h for chemical 24 h for physical in S1). An increase in the concentration of the active ingredient did not significantly speed up the onset of action of the evaluated preparations. However, the efficacy of Dergall and Bio PK decreased when the applied dose was halved, to 12% and 0% respectively. A decrease in the dose Mite Max led to a somewhat smaller, but not statistically significant decrease in mite mortality rates (74%). The proposed method for evaluating acaricide efficacy can be helpful in selecting the most effective preparations and the optimal concentration of the working solution to be applied in commercial layer farms, thus reducing the costs associated with the eradication of D. gallinae. The developed method enables a reliable evaluation of acaricides with both a physical and chemical mode of action, and it supports observations of the parasites’ responses to the applied treatment.

PMID:35339937 | DOI:10.1016/j.psj.2022.101798

Int J Food Microbiol. 2022 Mar 17;370:109635. doi: 10.1016/j.ijfoodmicro.2022.109635. Online ahead of print.

ABSTRACT

Primary and secondary models were developed for quantitatively characterizing the survival of Listeria monocytogenes in soy-sauce based acidified Asian style products that do not undergo a thermal treatment. The objective of this study was to quantify the effect of food matrix properties on L. monocytogenes’ survival in soy sauce-based products. This quantification enables a product-specific estimation of 5-log reduction time to ensure a safe processing and management operation, to ultimately facilitate a science-based, safety-oriented product development process. A central composite design with four independent variables (pH, soy sauce, added NaCl and soluble solids) with five levels was used to plan the challenge studies on different formulations. To model microbial survival over time, different non-linear primary models were fit to the data obtained from challenge studies. The best-fit model was selected based on a series of statistical goodness-of-fit measures. Kinetic parameters estimated from the best-fit primary models were fit to response surface equations using second order polynomial regression. The best-fit primary model representative of the product formulations was a modified Weibull model. The natural logarithm of the scale parameter (δ, in h) was used as the response variable for the secondary model. This resulted in acceptable fitting compared to the observed values with R² values of 0.95 and RMSE of 0.7 h. External validity of model predictions was conducted by comparing them to 5-log reduction times observed in independent challenge tests using different product formulations. Results indicated an acceptable validation with R² = 0.81 and RMSE = 35 h. The present study provides quantitative tools specific for cold-fill-hold soy sauce-based products to enhance microbial safety management plans and product development.

PMID:35339915 | DOI:10.1016/j.ijfoodmicro.2022.109635

J Psychosom Res. 2022 Mar 22;157:110794. doi: 10.1016/j.jpsychores.2022.110794. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVE: Despite the availability of successful treatment approaches for chronic tinnitus, it has proven difficult to predict who profits from treatment and it is still an open question if it is possible at all. We tried to overcome methodological shortcomings and to predict treatment outcome indicated by questionnaires measuring tinnitus distress.

METHODS: This is an observational, prospective cohort study. Lasso and post-selection inference methods were used to predict treatment outcome in patients suffering from chronic tinnitus (N = 747). Patients were treated for five consecutive days in an interdisciplinary setting according to guidelines.

RESULTS: Early change, i.e. a positive response after the screening day, as well as change due to treatment was predicted by several psychopathological variables, but also tinnitus-related factors. Female gender as an example was a predictor for change due to treatment. In general, therapy success both for early change and change due to treatment cannot be predicted satisfactorily as indicated by a high mean cross-validation error (for early change: 9.83, for change due to treatment: 14.40). Analyzing sub-groups separated by tinnitus severity to reduce heterogeneity did not improve the situation and for patients with high tinnitus severity no predictors at all could be reported (cross-validated error: 11.62 for the low quartile, 13.38 for the low-medium quartile, and 15.61 for the medium-high quartile).

CONCLUSION: Several psychopathological and tinnitus-related variables predicted early and long-term change. Nevertheless, also overcoming methodological shortcomings to predict treatment success did not lead to satisfactory results, but rather emphasizes the high heterogeneity of chronic tinnitus.

PMID:35339906 | DOI:10.1016/j.jpsychores.2022.110794

J Zoo Wildl Med. 2022 Mar;53(1):126-132. doi: 10.1638/2021-0052.

ABSTRACT

Effective management of articular injuries in avian species is a known and frequent challenge. Potential treatments include many domestic animal therapeutics, such as Adequan®, which is used widely in dogs and horses. However, clinical reports have described hemorrhagic diatheses in a variety of avian species treated with varying doses and administration frequency of Adequan. This study investigated the hypocoagulability associated with parenteral administration of Adequan in avian species. Following a pilot dosing study in domestic chickens (Gallus gallus), citrated plasma from Chilean flamingos (Phoenicopterus chilensis) (n = 42) was spiked with Adequan to represent three dosing regimens (1 mg/kg, 5 mg/kg, 10 mg/kg). The fibrinogen content of plasma samples was determined and thrombin-clotting times (TCTs) were compared for the untreated (control) and spiked flamingo samples. The TCT for control and 1-mg/kg spiked plasma were not significantly different; however, both 5 mg/kg and 10 mg/kg spiked samples demonstrated significantly prolonged TCT (P-value < 0.0001) indicating hypocoagulability. These results support that Adequan given parenterally at 1 mg/kg can be utilized safely in clinical case management as an adjunctive treatment for osteoarthritis in flamingos and potentially other avian species.

PMID:35339157 | DOI:10.1638/2021-0052

J Zoo Wildl Med. 2022 Mar;53(1):31-40. doi: 10.1638/2020-0064.

ABSTRACT

This retrospective study evaluated whether six methods (glutamyltransferase, glutaraldehyde coagulation test, sodium sulfite precipitation test, total serum protein, glucose, and fibrinogen) used to assess passive transfer status in ruminants were predictive of survival of nondomestic Caprinae neonates in a zoological collection. A total of 184 neonates from 10 nondomestic Caprinae species had one or more testing methods performed within 7 d of birth. Results of each test were compared with the clinical condition (alive or dead) at 7, 30, and 90 d of age. Total protein (TP) results were not considered for statistical significance in this study. No statistical correlations between results of the serum gamma glutamyltransferase (GGT), glutaraldehyde coagulation test, or sodium sulfite precipitation test (BOVA-S) and survival at any age were found. A higher glucose level within 7 d of birth was associated with a greater probability of survival. Fibrinogen levels were found to have a strong negative association with survival at 30 and 90 d. Increased glucose concentration was negatively associated with the probability of an infectious cause of mortality and the need for medical intervention. In contrast, increased fibrinogen levels were associated with higher probabilities of infectious death and the need for major medical care. Neonates who were confirmed to have nursed had a lower likelihood of requiring major medical intervention. These findings suggest that glucose and fibrinogen levels are better predictors of neonatal survival in nondomestic Caprinae when compared to the other three tests reviewed in this study. Using survival as an indicator of adequate passive transfer in this group of neonates failed to identify a gold standard of diagnosis of failure of passive transfer, so more than one diagnostic test should be utilized.

PMID:35339147 | DOI:10.1638/2020-0064

J Zoo Wildl Med. 2022 Mar;53(1):116-125. doi: 10.1638/2021-0085.

ABSTRACT

Chemical sedation of fish is often used during scientific research to reduce stress and risk of injury. Electric fish handling gloves (EFHG) have been proposed as a no-residue alternative to chemical immobilization. However, the impact of handling fish with EFHG on their physiology remains relatively poorly studied. Stress markers (plasma cortisol and lactate) and the impact on muscular integrity (plasma creatine kinase and histopathology of skeletal muscles) were assessed in brook trout (Salvelinus fontinalis) subjected to one of three immobilization methods (manual restraint, EFHG [10-16 mV], and buffered 60 mg/L tricaine methanesulfonate [MS-222] immersion anesthesia) for 1- and 5-min restraints. Plasma lactate levels were significantly higher 2 h postrestraint for all experimental groups (+242%; P < 0.001), but the magnitude of these increases was significantly lower in the MS-222 groups (P ≤ 0.0002). Plasma creatine kinase concentrations significantly increased 2 h postrestraint for the EFHG groups (+92%, P ≤ 0.0061), and this increase was significantly higher than in the MS-222 group for the 1-min restraint (P = 0.0031). Although there was no significant difference between the restraining methods tested at all time points for plasma cortisol, the EFHG and manual restraint groups showed a linear and statistically significant increase after the initial 5-min restraint, whereas all other groups presented an expected bell-shaped profile with a plasma peak 1 h after the initial restraint. One fish in the manual restraint group died during the 5-min restraint, and two fish from the EFHG group were euthanized at the end of this protocol because of buoyancy anomalies. All other fish from the 5-min restraint group developed cutaneous saprolegniasis 3 wk after the experiments. The evaluation of the safety of EFHG in brook trout showed similar impacts on the variables tested compared with manual restraint for 1- and 5-min immobilizations.

PMID:35339156 | DOI:10.1638/2021-0085