scholarly journals Relationship between habitat distribution, growth rate, and plasticity in congeneric larval dragonflies

2005 ◽  
Vol 83 (8) ◽  
pp. 1128-1133 ◽  
Author(s):  
S J McCauley
Keyword(s):  
Growth Rate ◽  
Predation Risk ◽  
Growth Rates ◽  
Lepomis Macrochirus ◽  
Negative Relationship ◽  
Activity Level ◽  
Activity Levels ◽  
Habitat Distribution ◽  
Invertebrate Predators ◽  
The Relationship

The relationship between habitat distribution, growth rate, and plasticity was examined in the larvae of three species of dragonfly in the genus Libellula L., 1758. Growth rates were compared under three conditions: in the absence of predation risk, in the presence of sunfish (Lepomis macrochirus Rafinesque, 1819; Pisciformes: Centrachidae), and in the presence of invertebrate predators. I assessed how the habitat distributions of the three species of dragonfly, specifically how commonly they occur with fish, were related to growth rates and to the level of growth plasticity under different levels of perceived predation risk. There was a negative relationship between growth rate and the frequency with which species coexist with sunfish. Growth-rate plasticity was limited and does not appear to be important in determining the ability of species to coexist with alternative top predator types. Only one species exhibited growth-rate plasticity, decreasing growth in response to the predator with which it most commonly coexists but not to the species which poses the greatest predation risk. A comparison of growth rates and activity levels in the presence and absence of these predators suggests that growth and activity level parallel each other in these species.

Maximal Oxygen Uptake and Daily Physical Activity in 7- to 12-Year-Old Boys

1993 ◽  
Vol 5 (4) ◽  
pp. 357-366 ◽  
Author(s):  
Hazzaa M. Al-Hazzaa ◽  
Mohammed A. Sulaiman
Keyword(s):  
Physical Activity ◽  
Heart Rate ◽  
Oxygen Uptake ◽  
Maximal Oxygen Uptake ◽  
Open Circuit ◽  
Daily Physical Activity ◽  
Activity Level ◽  
Activity Levels ◽  
School Time ◽  
The Relationship

The present study examined the relationship between maximal oxygen uptake (V̇O2max) and daily physical activity in a group of 7- to 12-year-old boys. V̇O2max was assessed through the incremental treadmill test using an open circuit system. Physical activity level was obtained from heart rate telemetry outside of school time for 8 hrs during weekdays and during 40 min of physical education classes. The findings indicated that the absolute value of V̇O2max increased with age, while relative to body weight it remained almost the same across age, with a mean of 48.4 ml · kg−1 · min−1. Moreover, heart rate telemetry showed that the boys spent a limited amount of time on activities that raise the heart rate to a level above 160 bpm (an average of 1.9%). In addition, V̇O2max was found to be significantly related to the percentage of time spent at activity levels at or above a heart rate of 140 bpm, but not with activity levels at or above a heart rate of 160 bpm.

scholarly journals Mindsets Predict Physical Activity and Relate to Chosen Management Strategies in Individuals with Knee Osteoarthritis

2021 ◽  
Author(s):  
Melissa A. Boswell ◽  
Kris M. Evans ◽  
Sean R. Zion ◽  
Danielle Z. Boles ◽  
Jennifer L. Hicks ◽  
...  
Keyword(s):  
Physical Activity ◽  
Knee Osteoarthritis ◽  
Online Survey ◽  
Management Strategies ◽  
The Elderly ◽  
Activity Level ◽  
Activity Levels ◽  
Group A ◽  
Test Retest Reliability ◽  
The Relationship

Objectives. We compared mindsets about physical activity among those with and without knee osteoarthritis and investigated if these mindsets relate to physical activity level and symptom management. Methods. Participants with (n=150) and without (n=152) knee osteoarthritis completed an online survey at study enrollment (T1). Participants with knee osteoarthritis repeated the survey three weeks later (T2; n=62). The mindset questionnaire, scored from 1-4, assessed the extent to which individuals associate the process of exercising with less appeal-focused qualities (e.g., boring, painful, isolating, and depriving) vs. appeal-focused (e.g., fun, pleasurable, social, and indulgent) versus. Using linear regression, we examined the relationship between mindset and having knee osteoarthritis, and, in the subgroup of participants with knee osteoarthritis, the relationship between mindset at T1 and physical activity (via the Physical Activity Scale for the Elderly) at T2. We also compared mindsets between those who use medication for management and those who use exercise. Results. A less appeal-focused mindset regarding physical activity was marginally associated with having knee osteoarthritis (β=-0.125, P=0.096). Within the knee osteoarthritis group, a more appeal-focused mindset predicted higher future physical activity (β=20.68, P=0.039), controlling for current physical activity, demographics, and health. Individuals that used exercise with or without pain medication or injections had more appeal-focused process mindsets than those who used medication or injections without exercise (P<0.001). Further, the process mindset inventory demonstrated strong internal consistency (α=0.92 at T1 for n=150 and α=0.92 at T2 for n=62) and test-retest reliability (ICC>0.841, P<0.001) within the knee osteoarthritis population. Conclusion. In individuals with knee osteoarthritis, mindsets predict future physical activity levels and relate to an individual's management strategy. Mindsets are a reliable and malleable construct and may be a valuable target for increasing physical activity and improving adherence to rehabilitation strategies involving exercise among individuals with knee osteoarthritis.

Examining the Relationship Between Heart Rate and Problem Behavior: A Case Study of Severe Skin Picking in Prader-Willi Syndrome

2013 ◽  
Vol 118 (6) ◽  
pp. 460-474 ◽  
Author(s):  
Scott S. Hall ◽  
Jennifer L. Hammond ◽  
Kristin M. Hustyi
Keyword(s):  
Heart Rate ◽  
Functional Analysis ◽  
Single Case ◽  
Automatic Reinforcement ◽  
Activity Level ◽  
Prader Willi Syndrome ◽  
Activity Levels ◽  
Skin Picking ◽  
The Relationship

Abstract Few studies have examined the relationship between heart rate and self-injurious behavior (SIB) shown by individuals with IDD (intellectual and developmental disabilities). In this single-case study, we simultaneously monitored heart rate and activity levels during a functional analysis of severe skin picking behavior exhibited by a young man with Prader-Willi syndrome (PWS). Results of the functional analysis indicated that the participant's skin picking was maintained by automatic reinforcement. A within-session analysis of the data indicated that skin picking bouts resulted in an increase in heart rate, suggesting a positive- automatic reinforcement function. These data indicate that inclusion of heart rate and activity-level monitoring during a functional analysis may provide important additional information concerning the determinants of SIB.

Growth Rate Responses of Lotic Periphytic Diatoms to Experimental Phosphorus Enrichment: The Influence of Temperature and Light

1988 ◽  
Vol 45 (2) ◽  
pp. 261-270 ◽  
Author(s):  
Max L. Bothwell
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Phosphorus Enrichment ◽  
Enrichment Experiments ◽  
Community Growth ◽  
Specific Growth Rates ◽  
The Relationship ◽  
River Water Temperature

Phosphate enrichment experiments were conducted year-round at the experimental troughs research apparatus (EXTRA) on the South Thompson River in British Columbia to determine the relationship between external concentration of orthophosphate and the growth rates of lotic periphytic diatom communities. Growth rate saturation always occurred at a phosphate concentration of approximately 0.3–0.6 μg P∙L−1. The maximum growth rate (μmax-P) with phosphorus enrichment varied seasonally with temperature. The relative specific growth rates (μ:μmax-P) as a function of external phosphate were constant. Seasonal changes in solar insolation (PAR) had no effect on the autotrophic community growth rates in unamended river water. Temperature exerted the most dominant influence on phosphorus-replete growth rates.

scholarly journals Effects of temperature on individual growth rate and body size of a freshwater amphipod

1998 ◽  
Vol 76 (6) ◽  
pp. 1107-1116 ◽  
Author(s):  
Vadim E Panov ◽  
Donald J McQueen
Keyword(s):  
Growth Rates ◽  
Negative Relationship ◽  
Maximum Size ◽  
Growth Efficiency ◽  
Individual Growth ◽  
Summer Temperatures ◽  
Individual Growth Rate ◽  
Natural Temperature ◽  
Effects Of Temperature ◽  
The Relationship

Individual growth rates of the freshwater amphipod Hyalella azteca (Saussure) were measured in the littoral zone oftwo small oligotrophic Ontario lakes and in growth experiments over a natural temperature gradient (10, 15, 20, and 238C).Field observations showed that a temperature of 208C is important for both the induction and termination of reproductiveresting stages in H. azteca. Growth rates were more affected by temperature in small than in large individuals. Growthparameters are related to rearing temperature by linear regressions, which can be used as a simple model for bioenergeticscalculations in crustaceans. A negative relationship between water temperature and maximum size attained by the amphipodswas found. The largest adults were absent in studied populations when summer temperatures were high, and this phenomenon,which has also been observed in other aquatic invertebrates, was bioenergetically determined. Energy-budget estimationsshowed negative net growth efficiency (K2) in the largest adults at temperatures above 208C. The relationship between K2andtemperature showed a dome-shaped pattern, K2values for larger amphipods being maximal at lower temperatures. Seasonalmigrations of adult H. azteca from shallow littoral to deeper cold habitats, observed in lakes during the warmest periods, appearto be temperature-induced and bioenergetically advantageous, despite probable increases in predation risk experienced inspatially simple deep-water habitats.

scholarly journals Low ADAMTS13 Activity Correlates with Increased Mortality in COVID-19 Patients

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S6-S7
Author(s):  
Joseph Sweeney ◽  
Mohammad Barouqa ◽  
Gregory Krause ◽  
Jesus Gonzalez Lugo ◽  
Shafia Rahman ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Hospitalized Patients ◽  
Activity Level ◽  
Activity Levels ◽  
Adamts13 Activity ◽  
Cut Point ◽  
Von Willebrand ◽  
The Relationship ◽  
Willebrand Factor ◽  
D Dimer

Abstract Systemic inflammation and coagulopathy are characteristic hallmarks of COVID19. “COVID coagulopathy” manifests mainly as a prothrombotic state affecting both large and small blood vessels, and presenting as arterial, venous, and microangiopathic thrombotic events with von Willebrand factor (VWF) and soluble thrombomodulin increased in hospitalized patients. The causes of coagulopathy are poorly understood. Aim: To investigate the relationship between von Willebrand factor (VWF) biomarkers, intravascular hemolysis, coagulation, and organ damage in COVID19 patients and to study their association with disease severity and mortality. Methods: 181 hospitalized adult COVID19 patients were randomly selected with a balanced distribution of survivors and non-survivors during the period of March 26th 2020 to May 5th 2020. The medical records and laboratory values were reviewed. Statistical analysis was performed using R studio V.3.6.2. Results: Patients who died (n=90) had significantly lower ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity, elevated lactate dehydrogenase levels, increased schistocyte/RBC fragment counts, and elevated VWF antigen and activity levels compared to patients discharged alive (n=91). In 31 patients, we measured several of these biomarkers on two or more occasions. The trending of ADAMTS13 activity illustrated that it is not steady throughout the hospitalization course. ADAMTS13 activity levels tended to improve and/or reach normal levels in patients that survived, yet ADAMTS13 activity levels worsened in most patients that died. Likewise, the VWF antigen and activity levels tended to decrease in patients that survived whereas tended to increase well above the normal range (2-3 folds) in patients that died. D-Dimer levels trended downwards in survivors, sometimes to levels less than 1 µg/ml, yet tended to increase in patients who died. Given the relationship between ADAMTS13 activity and mortality, we wanted to determine a cut-point of initial ADAMTS13 activity (within 72 hours from admission) to predict mortality. 102 patients in our cohort had an ADAMTS13 activity measurement within this timeframe. We determined that this optimal cut-point of initial ADAMTS13 activity was 43% using Youden’s J statistic. Only 30% of patients who had an ADAMTS13 activity level of less than 43% on admission survived, yet 60% of patients survived who had an ADAMTS13 activity level of greater than 43% on admission. Conclusions: COVID-19 may present with low ADAMTS13 activity in a subset of hospitalized patients. Presence of schistocytes/RBC fragment and elevated D-dimer levels on admission may warrant a work-up for ADAMTS13 activity and VWF antigen and activity levels. These findings indicate the need for future investigation to study the relationship between endothelial and coagulation activation and the efficacy of treatments aimed at prevention and/or amelioration of microangiopathy in COVID-19.

The Relationship Between Physical Activity Levels and Pain in Children with Juvenile Idiopathic Arthritis

2013 ◽  
Vol 41 (2) ◽  
pp. 345-351 ◽  
Author(s):  
Elizaveta Limenis ◽  
Haddas A. Grosbein ◽  
Brian M. Feldman
Keyword(s):  
Physical Activity ◽  
Juvenile Idiopathic Arthritis ◽  
Rating Scale ◽  
Numerical Rating Scale ◽  
Activity Level ◽  
Pain Interference ◽  
Activity Levels ◽  
Healthy Children ◽  
Physical Activity Levels ◽  
The Relationship

Objective.Pain and reduced physical activity levels are common in children with juvenile idiopathic arthritis (JIA). Currently, there is no consensus about the role of physical activity in managing pain in JIA. The purpose of our study was to assess the relationship between physical activity level and pain in children ages 11 to 18 years with JIA.Methods.A random sample of 50 patients with JIA were approached by mailed questionnaires. Physical activity was determined using the Physical Activity Questionnaire (PAQ). Pain measures included the Numerical Rating Scale (pain severity), SUPER-KIDZ body diagram (number of painful areas), and the Child Activities Limitations Inventory-21 (pain interference). Generalized linear models were used to assess the relationship between physical activity and pain, as well as the roles of sex and age.Results.The response rate was 84%. Thirty-four respondents completed the questionnaire package. The median age was 15 years. The mean PAQ score was 2.16/5. Physical activity declines with increasing age in youth with JIA (r = 0.53, p = 0.0014). Lower physical activity is associated with greater pain interference (r = 0.39, p = 0.0217) and more severe pain (r = 0.35, p = 0.0422).Conclusion.Children with JIA report significantly less activity than healthy children based on PAQ scores, with physical activity declining throughout adolescence. Physical activity is inversely related to pain interference and severity in children with JIA. Our findings suggest that physical activity interventions may play an important role in the management of pain in JIA.

The effect of growth rate on muscle distribution in sheep

1975 ◽  
Vol 85 (1) ◽  
pp. 189-191 ◽  
Author(s):  
D. M. Murray ◽  
Olga Slezacek
Keyword(s):  
Growth Rate ◽  
Weight Loss ◽  
Growth Rates ◽  
Live Weight ◽  
High Growth ◽  
Growth Path ◽  
Merino Sheep ◽  
Reported Data ◽  
Relationship Of ◽  
The Relationship

There is little information available on the effect of growth rate on muscle distribution in sheep. Although Lohse, Moss & Butterfield (1971) and Lohse (1973) have reported data on muscle distribution of Merino sheep, the growth rates of animals in both these studies were neither controlled nor reported. In another experiment using Merino sheep, Lohse, Pryor & Butterfield (1973) studied the effect of a period of live-weight loss on the relationship of selected muscles to total side muscle during subsequent re-alimentation. They found that the interrupted growth path decreased the proportion of total side muscle formed by the weight of ten muscles which had previously been classified as muscles with a high growth impetus (Lohse, 1971). Data are presented herein for the muscle distribution of sheep grown along three growth paths.

Ear branching as a means of increasing grain uniformity in wheat

1972 ◽  
Vol 23 (4) ◽  
pp. 551 ◽  
Author(s):  
HM Rawson ◽  
KN Ruwali
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Grain Growth ◽  
Growth Rates ◽  
Grain Filling ◽  
Size At Maturity ◽  
Grain Number ◽  
Photosynthetic System ◽  
Temperature Changes ◽  
The Relationship

Grain growth was compared in two field-grown wheats, Kalyan Sona, a high-yielding, seinidwarf line with few spikelets per ear and many grains per spikelet, and a branched-eared cultivar with many spikelets, each with few grains. The basis of comparison was the spikelet in Kalyan Sona and the branch in the branched material. Within the central spikelets of the main ear in Kalyan Sona, grain growth rates for the greater part of filling were b > a = c > d > e; final weights per grain for these florets were 42, 40, 37,26, and 12 mg respectively. The gradation in growth rate for the eight grains along the branch in the branched-eared cultivar was relatively small with the consequence that all grains were similar in size at maturity (range 39–43 mg); peak growth rates for all positions were at least as high as for grains a, b, and c in Kalyan Sona. In another cultivar, Triple Dirk, increasing competition for assimilates by reducing the light intensity during grain filling had a differential effect on grains within the spikelet but scarcely on the pattern between spikelets. The relationship between all grains was unaffected by temperature changes. The results are discussed in relation to competition for assimilates between grains, and the suggestion made that a high number of grains per spikelet may not use the available assimilates most efficiently. Ear branching is proposed as a preferable alternative, as this also provides abundant grain sites to utilize assimilates to the potential of the photosynthetic system, yet ensures grain uniformity per ear, regardless of grain number, by having few grains in each spikelet.

Relationship between body size and population growth rate in two opportunistic polychaetes

2002 ◽  
Vol 82 (3) ◽  
pp. 403-408 ◽  
Author(s):  
D. Prevedelli ◽  
R. Simonini
Keyword(s):  
Growth Rate ◽  
Body Size ◽  
Sex Ratio ◽  
Population Growth ◽  
Growth Rates ◽  
Life Histories ◽  
Population Growth Rate ◽  
Population Growth Rates ◽  
The Relationship ◽  
Dinophilus Gyrociliatus

The relationship between body size and population growth rate λ has been studied in two species of opportunistic polychaetes, Dinophilus gyrociliatus and Ophryotrocha labronica, which colonize harbour environments. These species exhibit a semi-continuous iteroparous reproductive strategy, are phylogenetically closely-related but differ in body size and in some aspects of their sexuality. Ophryotrocha labronica is about 4 mm in body length, displays only slight sexual dimorphism and its sex ratio is biased towards the female sex in the ratio 2:1. Dinophilus gyrociliatus is about 1 mm in length, the males are extremely small and the sex ratio is strongly biased (3:1) in favour of the females. In spite of the considerable differences in all traits of their life histories and in many demographic parameters, the growth rates of the two populations are very similar. The analyses carried out have shown that the rapid attainment of sexual maturity of D. gyrociliatus gives it an advantage that offsets the greater fecundity of O. labronica. It is very likely that the reproductive peculiarities of D. gyrociliatus help to raise the population growth rates. The ‘saving’ on the male sex achieved both by the shift of the sex ratio in favour of the females and by the reduction in the males' body size would appear to enable D. gyrociliatus to grow at the same rate as O. labronica, a larger and more fecund species.

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