scholarly journals Time of night and moonlight structure vertical space use by insectivorous bats in a Neotropical rainforest: an acoustic monitoring study

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10591
Author(s):  
Dylan G.E. Gomes ◽  
Giulliana Appel ◽  
Jesse R. Barber

Background Previous research has shown diverse vertical space use by various taxa, highlighting the importance of forest vertical structure. Yet, we know little about vertical space use of tropical forests, and we often fail to explore how this three-dimensional space use changes over time. Methods Here we use canopy tower systems in French Guiana and passive acoustic monitoring to measure Neotropical bat activity above and below the forest canopy throughout nine nights. We use a Bayesian generalized linear mixed effect model and kernel density estimates to demonstrate patterns in space-use over time. Results We found that different bats use both canopy and understory space differently and that these patterns change throughout the night. Overall, bats were more active above the canopy (including Cormura brevirostris, Molossus molossus, Peropteryx kappleri and Peropteryx macrotis), but multiple species or acoustic complexes (when species identification was impossible) were more active in the understory (such as Centronycteris maximiliani, Myotis riparius, Pteronotus alitonus and Pteronotus rubiginosus). We also found that most bats showed temporally-changing preferences in hourly activity. Some species were less active (e.g., P. kappleri and P. macrotis), whereas others were more active (Pteronotus gymnonotus, C. brevirostris, and M. molossus) on nights with higher moon illuminance. Discussion Here we show that Neotropical bats use habitat above the forest canopy and within the forest understory differently throughout the night. While bats generally were more active above the forest canopy, we show that individual groups of bats use space differently over the course of a night, and some prefer the understory. This work highlights the need to consider diel cycles in studies of space use, as animals use different habitats during different periods of the day.

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Yandi Zhu ◽  
Haiyan Zhu ◽  
Qinyu Dang ◽  
Qian Yang ◽  
Dongxu Huang ◽  
...  

Abstract Background Blood lipid increases during gestation are considered a physiological adaption, and decrease after delivery. However, some adverse pregnancy outcomes are thought to be related to gestational lipid levels. Therefore, it is necessary to have a reference range for lipid changes during gestation. The present study aims to describe triglyceride (TG) changes during pregnancy and 42 days postpartum and to find cut-off points for TG levels during the first, second, and third trimesters. Methods A total of 908 pregnant women were followed from recruitment to 42 days postpartum, and their serum lipids were collected at gestational weeks 6–8, 16, 24, and 36 and 42 days postpartum. The major outcome was postpartum hypertriglyceridemia. The association between gestational and postpartum TG levels was analysed by stepwise multiple linear regression. A two-stage approach including a linear mixed-effect model and linear or logistic regression was conducted to explore the contribution of the changes in TG over time in pregnancy to postpartum hypertriglyceridemia. Logistic regression was constructed to examine the association between gestational TG levels and postpartum hypertriglyceridemia. Cut-off points were calculated by receiver operating characteristic (ROC) curves. Results There was a tendency for serum TG to increase with gestational age and decrease at 42 days postpartum. Prepregnancy overweight, obesity, and GDM intensified this elevation. Higher TG levels at gestational weeks 6–8, 16, 24, and 36 were positively associated with a higher risk of postpartum hypertriglyceridemia [OR 4.962, 95 % CI (3.007–8.189); OR 2.076, 95 % CI (1.303–3.309); OR 1.563, 95 % CI (1.092–2.236); and OR 1.534, 95 % CI (1.208–1.946), respectively]. The trend of the change in TG over time was positively associated with the TG level and risk of postpartum hypertriglyceridemia [OR 11.660, 95 % CI (6.018–22.591)]. Based on ROC curves, the cut-off points of serum TG levels were 1.93, 2.35, and 3.08 mmol/L at gestational weeks 16, 24, and 36, respectively. Stratified analysis of prepregnancy body mass index (pre-BMI) and GDM showed that higher gestational TG was a risk factor for postpartum hypertriglyceridemia in women with normal pre-BMI and without GDM. Conclusions Gestational TG and its elevation were risk and predictive factors of postpartum hypertriglyceridemia, especially in pregnant women with normal pre-BMI or without GDM.


2021 ◽  
Vol 9 (4) ◽  
pp. 36
Author(s):  
Vittorio Checchi ◽  
Marco Montevecchi ◽  
Luigi Checchi

Since aerosol continuously persists in dental settings, where different procedures and patients come in succession, the use of oronasal masks is highly recommended. Among them, respirators known as Filtering Face Pieces (FFP) show a protective superiority compared to surgical masks. Even concerning respirators classified as non-reusable, it is not known how many hours of use are necessary to compromise their filtering capacity. The aim of this study is to investigate the variations of filtering capacity of an FFP2 respirator over time, in order to safely optimize the timing of its use. Five respirators were worn by the same operator during clinical activity for different usage times (8, 16, 24, 32, 40 h), and one respirator was kept unused. All respirators underwent a bacterial filtration efficacy (BFE) test. T-test for paired data with Bootstrap technique and Wilcoxon test for paired data compared BFE values of the five tested FFP2s respectively at each time, and the areas with the corresponding values of the control respirator (FFp2-F). A generalized linear mixed effect model (GLM) was applied considering type of respirator and time as fixed effects and intercept as random effect. No significant statistical differences were present in the BFE of each time. Data obtained by the present study highlight the important ability of FFP2s to maintain their BFE over time, suggesting a long lasting protective function.


The Auk ◽  
2014 ◽  
Vol 131 (4) ◽  
pp. 681-693 ◽  
Author(s):  
Nathan W. Cooper ◽  
Thomas W. Sherry ◽  
Peter P. Marra

Author(s):  
Jürgen Jost

AbstractThe main thesis developed in this article is that the key feature of biological life is the a biological process can control and regulate other processes, and it maintains that ability over time. This control can happen hierarchically and/or reciprocally, and it takes place in three-dimensional space. This implies that the information that a biological process has to utilize is only about the control, but not about the content of those processes. Those other processes can be vastly more complex that the controlling process itself, and in fact necessarily so. In particular, each biological process draws upon the complexity of its environment.


2012 ◽  
Vol 83 (3) ◽  
pp. 376-380 ◽  
Author(s):  
Bradly Russell ◽  
Mark Skvara ◽  
Eric Draper ◽  
William R. Proffit ◽  
Ceib Philips ◽  
...  

ABSTRACT Objective: To assess changes in mandibular third molar angulation during orthodontic treatment in subjects having either first or second premolars or neither removed. Materials and Methods: In a retrospective study approved by the institutional review board, right and left mandibular third molar angulations were compared to the vertical axis of adjacent second molars before and at the end of orthodontic treatment. The sample included 25 subjects with first premolars removed, 25 subjects with second premolars removed, and 24 subjects with no premolars removed. A decrease in angulation over time of at least 5°, so that the third molar became more vertical, was considered clinically favorable. Data were assessed by a linear mixed effect model and a proportional odds model with significance set at P < .05. Results: Prior to treatment, the average mandibular third molar angulation did not differ significantly among the three study groups (P  =  .97). The average change during treatment was not significantly affected by group (P  =  .59), but a higher proportion of mandibular third molars were more vertical by at least 5° in the second premolar extraction group compared to the other two groups at the completion of treatment. Conclusion: Although creating space for third molars to erupt and function has intuitive appeal, clinicians should not assume that third molars will move upright to a vertical position even if premolar removal is performed as part of an orthodontic treatment plan.


2019 ◽  
Vol 104 (5) ◽  
pp. 648-654 ◽  
Author(s):  
Yong Woo Kim ◽  
Won June Lee ◽  
Bo Ram Seol ◽  
Young Kook Kim ◽  
Jin Wook Jeoung ◽  
...  

BackgroundTo investigate the thinning rate of three-dimensional neuroretinal rim thickness (3D-NRT) in glaucoma eyes with optic disc haemorrhage (DH) and its relationship to retinal nerve fibre layer thickness (RNFLT) progression.MethodsNinety-five (95) eyes of 95 glaucoma patients with initial DH in the inferotemporal (n=69) and superotemporal (n=26) regions and 48 eyes of 48 glaucoma patients without DH were retrospectively reviewed. The rates of change for 3D-NRT and RNFLT were compared by linear mixed-effect model. For the direct comparison between 3D-NRT and RNFLT, dynamic-range-based normalised coefficient was used. The effect of DH frequency on the rates of thinning of 3D-NRT and RNFLT was evaluated.ResultsDuring a mean 7-year follow-up, the rates of thinning of 3D-NRT (–5.69±4.88 µm/year) and RNFLT (–2.03±2.03 µm/year) at 7 o’clock were faster than those at other locations (all p<0.05) in DH eyes. The dynamic-range-based normalised rate of thinning was significantly faster for RNFLT (–2.06%±1.62%/year) than for 3D-NRT (–1.15%±1.10%/year, p<0.001) in DH eyes, but not in non-DH eyes (p=0.43). DH frequency in the inferotemporal region was associated with the thinning rate of 3D-NRT as well as RNFLT.ConclusionDH eyes are associated with the progression of both 3D-NRT and RNFLT, especially in the inferotemporal region. DH eyes show a relatively faster thinning rate of average RNFLT than 3D-NRT. The frequency of DH can affect the progression of 3D-NRT as well as RNFLT.


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