WING MOVEMENTS AND LIFT REGULATION IN THE FLIGHT OF DESERT LOCUSTS

1993 ◽  
Vol 182 (1) ◽  
pp. 57-69 ◽  
Author(s):  
M. Wortmann ◽  
W. Zarnack
Keyword(s):  
Body Weight ◽  
Unsteady Aerodynamics ◽  
Movement Patterns ◽  
The Body ◽  
Three Dimensions ◽  
Body Angle ◽  
Wing Movement ◽  
Induced Changes ◽  
Lift Body

1. We simultaneously recorded lift/body weight, flight speed, body angle and 12 variables of wing movement for locusts performing tethered long-term flight with low movement scatter. The movements of the forewings and hindwings were recorded in three dimensions by means of miniature induction coils. 2. By adjusting the body angle, we could reproducibly manipulate lift generation as a consequence of induced changes in the wings' movement patterns. We were therefore able to analyse various relationships between the movement patterns and lift. 3. The most prominent variations of kinematic variables were observed for the forewing movements. The relative lift and the steady angle of pitch were positively correlated but there was a negative correlation between relative lift and pitching amplitude. We found no correlation between relative lift and flapping amplitude. Our results seem to correspond to a new theory about unsteady aerodynamics of oscillating aerofoils. 4. We sometimes observed variations in lagging. 5. The forewing downstroke was delayed by 0–8 ms following the hindwing downstroke. Relative lift was positively correlated to this delay.

Does the Body Image Exist in Three Dimensions? The Study of Visual Mental Representation of a Body and a Nonbody Object

2001 ◽  
Vol 92 (1) ◽  
pp. 223-233
Author(s):  
D. P. McCabe ◽  
D. I. Ben-Tovim ◽  
M. K. Walker ◽  
D. Pomeroy
Keyword(s):  
Spatial Information ◽  
Mental Image ◽  
The Body ◽  
Three Dimensions ◽  
Long Term Memory ◽  
Depth Information ◽  
Mental Images ◽  
Term Memory ◽  
3 Dimensional

Do the mental Images of 3-dimensional objects recreate the depth characteristics of the original objects' This investigation of the characteristics of mental images utilized a novel boundary-detection task that required participants to relate a pair of crosses to the boundary of an image mentally projected onto a computer screen. 48 female participants with body attitudes within expected normal range were asked to image their own body and a familiar object from the front and the side. When the visual mental image was derived purely from long-term memory, accuracy was better than chance for the front (64%) and side (63%) of the body and also for the front (55%) and side (68%) of the familiar nonbody object. This suggests that mental images containing depth and spatial information may be generated from information held in long-term memory. Pictorial exposure to views of the front or side of the objects was used to investigate the representations from which this 3-dimensional shape and size information is derived. The results are discussed in terms of three possible representational formats and argue that a front-view 2½-dimensional representation mediates the transfer of information from long-term memory when depth information about the body is required.

Transplacental Toxicity and Carcinogenesis Studies in Rats with Hexamethylenetetramine

1970 ◽  
Vol 56 (6) ◽  
pp. 325-334 ◽  
Author(s):  
Giuseppe Della Porta ◽  
José R. Cabral ◽  
Giorgio Parmiani
Keyword(s):  
Drinking Water ◽  
Body Weight ◽  
Wistar Rats ◽  
The Body ◽  
Carcinogenic Activity ◽  
Long Term Experiments ◽  
Pregnancy And Lactation ◽  
Successive Generations ◽  
And Control

In a previous paper (Fd Cosmet. Toxicol., 6: 707–715, 1968) it was reported that hexamethylenetetramine (HMT) had no carcinogenic activity in long-term experiments in mice and rats. In the present study, 12 ♀ and 6 ♂ Wistar rats were given 1% HMT in the drinking water starting 2 weeks before mating. The females were kept under treatment during pregnancy and lactation. A similar untreated group of 12 ♀ and 6 ♂ served as control. Twelve treated females and eleven controls became pregnant and gave birth to 124 and 118 babies respectively; no malformations were noted. From these animals, 24 for each sex were continued on the 1% HMT up to the 20th week of age or were kept untreated. The body weight of treated animals was significantly lower than that of controls one, only up to the 9th week of age for the males and up to the 13th week for the females. At the end of the treatment both groups were sacrificed; the weight of organs was identical in the treated and control animals; there were no gross or histological pathology. In a second experiment, rats were given 1% HMT in the drinking water for 3 successive generations, up to the age of 40 weeks in the F1 and F2 groups and of 20 weeks for F3. The three groups were composed of 13 ♂ and 7 ♀, 15 ♂ and 11 ♀, 12 ♂ and 12 ♂, respectively. In addition, a group of 16 ♂ and 16 ♀ descendants of 2% HMT treated parents, were given 2% HMT for 50 weeks. A group of 48 ♂ and 48 ♀ served as untreated controls. All groups were kept under observation for over 2 years of age. No evidence of carcinogenicity was found in any of the HMT-treated groups.

The influence of long-term melatonin administration on basic physiological and metabolic variables of young Wistar:Han rats

Biologia ◽  
2006 ◽  
Vol 61 (3) ◽  
Author(s):  
Monika Kassayová ◽  
Martina Marková ◽  
Bianka Bojková ◽  
Eva Adámeková ◽  
Peter Kubatka ◽  
...  
Keyword(s):  
Body Weight ◽  
Water Intake ◽  
Glucose Concentration ◽  
Tap Water ◽  
Serum Glucose ◽  
The Body ◽  
Male Rats ◽  
Epididymal Fat ◽  
Food And Water Intake

AbstractThe question of effects of long-term melatonin (MEL) administration have not yet been explained sufficiently, especially its metabolic consequences in young persons and animals. The aim of the present study was to analyze the effects of MEL given during prolonged time (for 3 months) and chronically (for 6 months) at the dose of 4 µg/mL of tap water, on the selected metabolic and hormonal parameters in young female and male Wistar:Han (WH) rats. The weights of selected organs, tissues, body weight gains and food and water intake were registered. Six weeks aged rats were adapted to standard housing conditions and light regimen L:D=12:12 h, fed standard laboratory diet and drank tap water (controls) or MEL solution ad libitum; finally they were sacrificed after overnight fasting. Prolonged MEL administration decreased serum glucose concentration and increased triacylglycerol and malondialdehyde concentration/content in the liver in females. In males MEL increased concentrations of serum phospholipids, corticosterone and liver malondialdehyde. MEL treatment reduced the body weight in both sexes and weight of epididymal fat in males, without any alterations of food and water intake. Chronic MEL administration reduced serum glucose concentration and increased concentration/content of glycogen, triacylglycerol and cholesterol in the liver and glycogen concentration/content in heart muscle in males. In females, the significant rise of serum corticosterone concentration and liver malondialdehyde content was recorded. MEL significantly increased liver weight and decreased thymus weight in males. MEL administration increased temporarily water intake in males, body and epididymal fat weights were similar to that in controls. Body weight of MEL drinking females was reduced in the 1st half of experiment only; the food and water intake did not differ from control group. The response in WH rats on MEL was more prominent as in the Sprague-Dawley strain (our previous studies). Male rats were generally more affected, probably due to higher daily and total consumption of melatonin.

scholarly journals Effects of long-term in vivo micro-CT imaging on hallmarks of osteopenia and frailty in aging mice

2020 ◽  
Author(s):  
Ariane C. Scheuren ◽  
Gisela A. Kuhn ◽  
Ralph Müller
Keyword(s):  
Body Weight ◽  
Aging Process ◽  
Frailty Index ◽  
Ct Imaging ◽  
Morphometric Parameters ◽  
The Body ◽  
The Other ◽  
Micro Ct

AbstractIn vivo micro-CT has already been used to monitor microstructural changes of bone in mice of different ages and in models of age-related diseases such as osteoporosis. However, as aging is accompanied by frailty and subsequent increased sensitivity to external stimuli such as handling and anesthesia, the extent to which longitudinal imaging can be applied in aging studies remains unclear. Consequently, the potential of monitoring individual mice during the entire aging process – from healthy to frail status – has not yet been exploited. In this study, we assessed the effects of long-term in vivo micro-CT imaging - consisting of 11 imaging sessions over 20 weeks - on hallmarks of aging both on a local (i.e., static and dynamic bone morphometry) and systemic (i.e., frailty index (FI) and body weight) level at various stages of the aging process. Furthermore, using a premature aging model (PolgA(D257A/D257A)), we assessed whether these effects differ between genotypes.The 6th caudal vertebrae of 4 groups of mice (PolgA(D257A/D257A) and PolgA(+/+)) were monitored by in vivo micro-CT every 2 weeks. One group was subjected to 11 scans between weeks 20 and 40 of age, whereas the other groups were subjected to 5 scans between weeks 26-34, 32-40 and 40-46, respectively. The long-term monitoring approach showed small but significant changes in the static bone morphometric parameters compared to the other groups. However, no interaction effect between groups and genotype was found, suggesting that PolgA mutation does not render bone more or less susceptible to long-term micro-CT imaging. The differences between groups observed in the static morphometric parameters were less pronounced in the dynamic morphometric parameters. Moreover, the body weight and FI were not affected by more frequent imaging sessions. Finally, we observed that longitudinal designs including baseline measurements at young adult age are more powerful at detecting effects of in vivo micro-CT imaging on hallmarks of aging than cross-sectional comparisons between multiple groups of aged mice subjected to fewer imaging sessions.

Hypothalamic control of photoperiod-induced cycles in food intake, body weight, and metabolic hormones in rams

2001 ◽  
Vol 281 (1) ◽  
pp. R76-R90 ◽  
Author(s):  
Gerald A. Lincoln ◽  
Stewart M. Rhind ◽  
Sueli Pompolo ◽  
Iain J. Clarke
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Sheep Model ◽  
Blood Concentrations ◽  
Metabolic Hormones ◽  
Melanocyte Stimulating Hormone ◽  
Induced Changes ◽  
And Control ◽  
Short Days

This study used a hypothalamo-pituitary disconnected (HPD) sheep model to investigate the central regulation of long-term cycles in voluntary food intake (VFI) and body weight (BW). VFI, BW, and circulating concentrations of metabolic hormones [α-melanocyte-stimulating hormone (α-MSH), insulin-like growth factor-1 (IGF-1), insulin, and leptin] were measured in HPD and control Soay rams exposed to alternating 16 weekly periods of long and short days for 80 wk. In the controls, the physiology was cyclical with a 32-wk periodicity corresponding to the lighting regimen. VFI and BW increased under long days to a maximum early into short days, and there were associated increases in blood concentrations of α-MSH, insulin, and leptin. In the HPD rams, there were no significant photoperiod-induced changes in any of the parameters. VFI increased after surgery for 8 wk and then gradually declined, although BW increased progressively and the HPD rams became obese. Concentrations of α-MSH, insulin, and leptin in peripheral blood were permanently increased (>200%), and levels of IGF-1 decreased (<55%). The HPD lesion effectively destroyed the entire median eminence [no nerve terminals immunostained for tyrosine hydroxylase (TH) and gonadotropin-releasing hormone] and the adjacent arcuate nucleus (no perikarya immunostained for proopiomelanocortin or TH, and no cells expressed neuropeptide Y mRNA). The results support the conclusion that arcuate hypothalamic systems generate long-term rhythms in VFI, BW, and energy balance.

scholarly journals Long-Term Effect of an AqueousFraxinus excelsiorL. Seed Extract in Spontaneously Hypertensive Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Noemi López-Carreras ◽  
Sandra Fernández-Vallinas ◽  
Marta Miguel ◽  
Amaya Aleixandre
Keyword(s):  
Blood Pressure ◽  
Body Weight ◽  
Spontaneously Hypertensive Rats ◽  
Seed Extract ◽  
The Body ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Arterial Blood ◽  
Plasma Antioxidant Capacity

The effect of long-term intake of different doses (20, 40, and 60 mg/kg/day) of aFraxinus excelsiorL. seed extract (FESE) on spontaneously hypertensive rats (SHR) was evaluated. Water was used as control and captopril (50 mg/kg/day) was used as positive control. Systolic blood pressure, body weight, and food and liquid intake were registered weekly in SHR. The antioxidant and vascular relaxing properties of FESE were also studied in these animals. The development of hypertension was attenuated in the groups treated with captopril or FESE. The antihypertensive effect was more accentuated in the captopril group than in the FESE groups, and it was paradoxically more accentuated in the groups treated with 20 mg/kg/day or 40 mg/kg/day of FESE than in the group treated with the highest dose of this extract. Body weight gain and food intake increased in the FESE groups. After removing the corresponding antihypertensive treatment, the arterial blood pressure and the body weight of the FESE treated animals returned to control values. In addition, FESE increased plasma antioxidant capacity and decreased plasma and liver malondialdehyde levels. Moreover, acetylcholine relaxation improved in the aorta rings from the FESE treated rats.

Physiological genetics of dietary restriction: uncoupling the body temperature and body weight responses

2007 ◽  
Vol 293 (4) ◽  
pp. R1522-R1527 ◽  
Author(s):  
Brad A. Rikke ◽  
Thomas E. Johnson
Keyword(s):  
Body Weight ◽  
Genetic Variation ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Dietary Restriction ◽  
The Body ◽  
Strain Variation ◽  
Long Term Effects ◽  
Difficult Challenge

Numerous physiological and molecular changes accompany dietary restriction (DR), which has been a major impediment to elucidating the causal basis underlying DR's many health benefits. Two major metabolic responses to DR that potentially underlie many of these changes are the body temperature ( Tb) and body weight (BW) responses. These responses also represent an especially difficult challenge to uncouple during DR. We demonstrate in this study, using two recombinant inbred (RI) panels of mice (the LXS and LSXSS) that naturally occurring genetic variation serves as a powerful tool for modulating Tb and BW independently during DR. The correlation coefficient between the two responses was essentially zero, with R = −0.04 in the LXS and −0.03 in the LSXSS, the latter averaged across replicate cohorts. This study is also the first to report that there is highly significant ( P = 10−10) strain variation in the Tb response to DR in the LXS (51 strains tested), with strain means ranging from 2 to 4°C below normal. The results suggest that the strain variation in the Tb response to DR is largely due to differences in the rate of heat loss rather than heat production (i.e., metabolic rate). This variation can thus be used to assess the long-term effects of lower Tb independent of BW or metabolic rate, as well as independent of food intake and motor activity as previously shown. These results also suggest that murine genetic variation may be useful for uncoupling many more responses to DR.

scholarly journals Estimation of Additive and Non-Additive Genetic Variances of Body Weight, Egg Weight and Egg Production for Quails (Coturnix coturnix japonica) with an Animal Model Analysis

2006 ◽  
Vol 49 (3) ◽  
pp. 300-307 ◽  
Author(s):  
N. Mielenz ◽  
R. R. Noor ◽  
L. Schüler
Keyword(s):  
Animal Model ◽  
Body Weight ◽  
Egg Production ◽  
Additive Model ◽  
The Body ◽  
Phenotypic Variance ◽  
Egg Weight ◽  
Term Selection ◽  
Inbreeding Coefficients

Abstract. This study estimates the additive and non-additive variances for egg production and body weight traits of two lines of quails from a long-term selection with the help of the REML method. For the body weight of 42-day-old females (BW42f) and males (BW42m), a total of 7,934 records for line 1 and 7,214 records for line 2 from 21 generations were used in our analyses. Additionally, 1,717 records of females from line 1 and 1,671 records of females from line 2 contained information on their egg production at an age of 42 to 200 days (EN200), on the average egg weight for the first 11 weeks of their laying season (EW1), on the average egg weight from weeks 12 to 23 (EW2), and on their body weight at an age of 200 days (BW200f). A multivariate additive animal model and one-trait dominance models, which include the inbreeding coefficients as covariates, were fitted to the data. The estimates of the heritability gained from our dominance models were smaller than those from the additive model. For line 1, the heritability values decreased for EN200 from 0.35 to 0.32, for EW1 from 0.66 to 0.56, for BW200f from 0.42 to 0.38, and for BW200m from 0.51 to 0.49, respectively. For the first line, the respective ratio (d2) of the dominance variance to the phenotypic variance for EN200, EW1, BW200f and BW200m was 0.08, 0.22, 0.09 and 0.21, and the values for the second line were 0.12, 0.06, 0.001 and 0.23.

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