body density
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2022 ◽  
Author(s):  
Julia Tiede ◽  
Benjamin Iuliano ◽  
Claudio Gratton

Abstract Context: Agricultural intensification is contributing to a global species decline. Underlying mechanisms include toxic effects of pesticides on non-target organisms and reductions in habitat and food availability. However, the effects of agricultural intensification on body condition, particularly of ecosystem service providing arthropods, are poorly understood.Objectives: Here, we investigated whether variations in the body condition of common lady beetle species (Coleoptera: Coccinellidae) can be explained by the composition and configuration of the surrounding landscape. Assuming strong seasonal variation in food availability in intensively farmed regions, we included the entire period of lady beetle activity in our study.Methods: Lady beetles were collected from April to September 2011 in 30 landscapes in southern Wisconsin, USA. We examined how body size, body density, and lipid content of the beetles responded to the percentage of intensive cropland, habitat diversity, and edge density in the surrounding landscape.Results: The strongest predictor of body condition was the percentage of intensive cropland. For every 10% increase in cropland, body density decreased by about 3.9% and fat content by 6.4%. Landscape diversity and edge density correlated with body condition of individual species.Conclusions: In agriculturally intensified landscapes, lady beetles with reduced body condition may produce fewer offspring, have lower survival rates, and exert less effective pest control. Thus, our results suggest a mechanistic link between landscape patterns and observed declines in lady beetle populations. Our results also show that the expansion of monocultures affects even common cropland-associated species such as Harmonia axyridis, suggesting a long-term decline in biocontrol services in simplified agricultural landscapes.


Author(s):  
M. Suárez ◽  
D. Fernández-González ◽  
C.F. Gutiérrez-González ◽  
L.A. Díaz ◽  
A. Borrell ◽  
...  

2021 ◽  
Vol 6 (3) ◽  
pp. 413-421
Author(s):  
Sapna Yadav ◽  
Gaurav Kadyan

Background: This study aimed to compare and correlate the resting heart rate, body composition and heart rate variability among judo and wushu players. Method: 40 athletes (20 judo and 20 wushu players) were included in the study. Body composition (BMI, subcutaneous body mass, skeletal body mass, body fat %, body density, Visceral fat, Lean body mass) was evaluated with the help of 7 skinfold thickness and body circumferences with the help of Harpenden calliper and measuring tape respectively. HRV (RMSSD, SDNN, LF/HF, LFnu and HFnu) was recorded in resting state (~5min) with the help of Heart wear shimmer ECG device. Result: No significant difference of body composition and HRV variables (p> 0.05) was found between the two groups except Body fat % and body density (p<0.05) which differ significantly among the two groups. In Judo, LF/HF and LFnu showed significant positive correlation with BMI (p<0.05, r=-0.488), subcutaneous whole-body mass (p<0.05, r=-0.464), visceral fat (p<0.05, r =-0.508), and body fat % (p<0.05, r =-0.626. Whereas HFnu showed significant negative correlation with BMI (p<0.05, r=-0.488), subcutaneous whole-body mass (p<0.05, r=-0.464), visceral fat (p<0.05, r=-0.505) and body fat % (p<0.05, r=-0.626). Whereas no correlation was found between HRV and Body composition in wushu players. Conclusion: Reduction in body fat % and visceral fat in judo players indicate improved sympathovagal balance which can be due to the adaptation induced by training loads. Similar results were not seen in wushu players because of high amount of body fat% and visceral fat. Keywords: Body composition, combat sports, heart rate variability, Body fat %, resting heart rate.


2021 ◽  
Vol 12 ◽  
pp. 61
Author(s):  
S. E. Massen

Shannon's information entropies in position- and momentum-space and their sum $S$ are calculated for various $s$-$p$ and $s$-$d$ shell nuclei using a correlated one-body density matrix depending on the harmonic oscillator size $b_0$ and the short range correlation parameter $y$ which originates from a Jastrow correlation function. It is found that the information entropy sum for a nucleus depends only on the correlation parameter $y$ through the simple relation $S= s_{0A} + s_{1A} y^{-\lambda_{sA}}$, where $s_{0A}$, $s_{1A}$ and $\lambda_{sA}$ depend on the mass number $A$. Finally, we propose a method to determine the correlation parameter from the above property of $S$ as well as the linear dependence of $S$ on the logarithm of the number of nucleons.


Author(s):  
Phan Thành Nam ◽  
Marcin Napiórkowski

AbstractWe consider the homogeneous Bose gas on a unit torus in the mean-field regime when the interaction strength is proportional to the inverse of the particle number. In the limit when the number of particles becomes large, we derive a two-term expansion of the one-body density matrix of the ground state. The proof is based on a cubic correction to Bogoliubov’s approximation of the ground state energy and the ground state.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 392
Author(s):  
Axel U. J. Lode ◽  
Sunayana Dutta ◽  
Camille Lévêque

We consider the dynamics of two-dimensional interacting ultracold bosons triggered by suddenly switching on an artificial gauge field. The system is initialized in the ground state of a harmonic trapping potential. As a function of the strength of the applied artificial gauge field, we analyze the emergent dynamics by monitoring the angular momentum, the fragmentation as well as the entropy and variance of the entropy of absorption or single-shot images. We solve the underlying time-dependent many-boson Schrödinger equation using the multiconfigurational time-dependent Hartree method for indistinguishable particles (MCTDH-X). We find that the artificial gauge field implants angular momentum in the system. Fragmentation—multiple macroscopic eigenvalues of the reduced one-body density matrix—emerges in sync with the dynamics of angular momentum: the bosons in the many-body state develop non-trivial correlations. Fragmentation and angular momentum are experimentally difficult to assess; here, we demonstrate that they can be probed by statistically analyzing the variance of the image entropy of single-shot images that are the standard projective measurement of the state of ultracold atomic systems.


2021 ◽  
Vol 17 (4) ◽  
pp. 2283-2293
Author(s):  
Derk P. Kooi ◽  
Timo Weckman ◽  
Paola Gori-Giorgi

2021 ◽  
Vol 14 (2) ◽  
pp. 90
Author(s):  
Serdar Geri

The purpose of this study is to investigate the differences between physical and some motoric characteristics of university students who participate in regular sports training and those who do not. A total of 20 volunteer students, 10 students with an average age of 20.80 &plusmn; 1.69 and 10 students with an average age of 19.90 &plusmn; 1.45 without any exercise habits were included in the study. Body circumference measurements, vertical-horizontal jump and strength, flexibility, body mass index, body fat ratio, body circumference measurements, vertical-horizontal jump and claw-back-leg strengths, flexibility, peak and average power values of the participant groups were determined and compared. SPSS 20.0 package program was used to analyze the data. Athlete Students&#39; body density, shoulder circumference, chest circumference, biceps (extension-flexion) circumference, average-peak strength, long-vertical jump, hand claw-back-leg strength were determined to be higher than non-athlete students (p&lt;0.05). Besides, students doing sports; body weight, body mass index, body fat ratio and waist circumference measurement averages were found to be lower than non-athletes (p&lt;0.05). As a result; it has been observed that the participation of young students in regular sports educations can be effective in preventing the risk of obesity and increases their motoric characteristics.


2021 ◽  
Vol 288 (1943) ◽  
pp. 20202307
Author(s):  
Kagari Aoki ◽  
Saana Isojunno ◽  
Charlotte Bellot ◽  
Takashi Iwata ◽  
Joanna Kershaw ◽  
...  

Monitoring the body condition of free-ranging marine mammals at different life-history stages is essential to understand their ecology as they must accumulate sufficient energy reserves for survival and reproduction. However, assessing body condition in free-ranging marine mammals is challenging. We cross-validated two independent approaches to estimate the body condition of humpback whales ( Megaptera novaeangliae ) at two feeding grounds in Canada and Norway: animal-borne tags ( n = 59) and aerial photogrammetry ( n = 55). Whales that had a large length-standardized projected area in overhead images (i.e. whales looked fatter) had lower estimated tissue body density (TBD) (greater lipid stores) from tag data. Linking both measurements in a Bayesian hierarchical model to estimate the true underlying (hidden) tissue body density (uTBD), we found uTBD was lower (−3.5 kg m −3 ) in pregnant females compared to adult males and resting females, while in lactating females it was higher (+6.0 kg m −3 ). Whales were more negatively buoyant (+5.0 kg m −3 ) in Norway than Canada during the early feeding season, possibly owing to a longer migration from breeding areas. While uTBD decreased over the feeding season across life-history traits, whale tissues remained negatively buoyant (1035.3 ± 3.8 kg m −3 ) in the late feeding season. This study adds confidence to the effectiveness of these independent methods to estimate the body condition of free-ranging whales.


Author(s):  
Stefano Di Sabatino ◽  
Claudio Verdozzi ◽  
Pina Romaniello

The one-body density matrix has recently attracted considerable attention as promising key quantity for the description of systems out of equilibrium. Its time evolution is given in terms of the...


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