The decline of a large yellow-footed rock-wallaby (Petrogale xanthopus) colony following a pulse of resource abundance

2010 ◽  
Vol 32 (2) ◽  
pp. 99 ◽  
Author(s):  
Andy Sharp ◽  
Hamish McCallum
Keyword(s):  
Carrying Capacity ◽  
Marked Reduction ◽  
Total Population ◽  
Population Increase ◽  
Population Estimates ◽  
Strong Positive Correlation ◽  
Short Term ◽  
Visual Survey ◽  
Average Rainfall ◽  
Exponential Rates

The dynamics of a yellow-footed rock-wallaby (Petrogale xanthopus) colony in central-western Queensland were monitored between spring 1991 and winter 1994. The two years immediately before the study witnessed well above average rainfall, while average rainfall was recorded during the period of the study. Both trapping and standardised visual survey data were modelled using the Jolly–Seber–Cormack (JSC) mark–recapture estimator and the Minta–Mangel (MM) mark–resight estimator. The JSC population estimates were considerably lower than those derived from the MM estimator, indicating that the trapping program sampled only a portion of the total population. Nevertheless, a strong degree of correlation existed between both estimators, suggesting that the dynamics of the trappable subpopulation mirrored those of the total population. The colony declined markedly in size throughout the study (103 to 48 individuals, winter 1992 to winter 1994, JSC estimates; 175 to 116 individuals, summer 1993 to winter 1994, MM estimates). No significant correlations (P > 0.05) were found between seasonal and/or biannual exponential rates of population increase (r) and environmental variables. Nevertheless, a strong positive correlation was observed between biannual r and short-term rainfall (r = 0.90) and pasture conditions (r = 0.85–0.93), suggesting that the colony was influenced to some extent by fluctuations in available resources. Annual r was calculated at –0.29 (1992–93) and –0.49 (1993–94). The marked reduction in colony size suggested that it was declining towards its average carrying capacity, following a strong pulse of recruitment linked to the above-average rainfalls of 1990.

scholarly journals Short-term movement patterns, population estimates and breeding biology of an island endemic bird, the Tristan Thrush

2019 ◽  
Vol 27 (4) ◽  
pp. 245-252
Author(s):  
Peter G. Ryan ◽  
Ben J. Dilley ◽  
Delia Davies ◽  
Trevor Glass ◽  
Fitsum Abadi
Keyword(s):  
Total Population ◽  
Data Augmentation ◽  
Local Population ◽  
Population Estimates ◽  
Limited Information ◽  
Short Term ◽  
Main Island ◽  
Island Endemic ◽  
Core Study ◽  
Land Bird

AbstractThe Tristan Thrush Turdus eremita is the only land bird that survived human colonisation of the main island of Tristan da Cunha and is listed as “Near Threatened”. Population estimates are confounded by the thrushes’ inquisitive and gregarious nature as well as limited information on their movements. We report the first measures of nest densities on Nightingale Island: 6 nests·ha-1 in Phylica arborea woodland and 4–5 nests·ha-1 in tussock habitat, which suggests that the population is approximately double the previous estimate. At Inaccessible Island, we individually color ringed 110 thrushes over two months to track their short-term movements and estimate the local population size. Individuals moved up to 950 m along the coast, but 96% of resightings were < 100 m. A Bayesian data augmentation approach estimated that some 260 thrushes visited the core study area, a 200-m stretch of cobble and boulder beach where birds come to drink, bathe and forage. This result suggests that the population on Inaccessible Island also is substantially larger than reported previously. We estimate the total population to be 8000–15,000 Tristan Thrushes. The main need is a population estimate for the nominate subspecies on the main island of Tristan.

Critical analysis and unique management of Gridhrasi w.s.r. to Sciatica - A Case Report

2018 ◽  
Vol 3 (4) ◽  
Author(s):  
Dr. Rangarajan B. ◽  
Dr. Muralidhara .
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Case Report ◽  
Total Population ◽  
The Body ◽  
Walking Distance ◽  
Common Symptom ◽  
Low Back ◽  
Short Term ◽  
Lower Back

Gridhrasi (Sciatica) is a disorder in which low back pain is found, that spreads through the hip, to the back of the thigh and down the inside of the leg. Mechanical low back pain (LBP) remains the second most common symptom related reason for seeing a physician. 85% of total population will experience an episode of mechanical LBP at some point during their lifetime. Fortunately, the LBP resolves for the vast majority within 2-4 weeks. There are many causes for low back pain, however true sciatica is a symptom of inflammation or compression of the sciatica nerve. The sciatica nerve carries impulses between nerve roots in the lower back and the muscles and nerve of the buttocks, thighs and lower legs. Compression of a nerve root often occurs as a result of damage to one of the discs between the vertebrae. In some cases, sciatic pain radiate from other nerves in the body. This is called referred pain. Pain associated with sciatica often is severe, sharp and shooting. It may be accompanied by other symptom, such as numbness, tingling, weakness and sensitivity to touch. There is only conservative treatment giving short term relief in pain or surgical intervention with side effect. But these are not successful and therefore those who are suffering from this are always in search of result oriented remedy. Walking distance and SLR test were taken for assessment parameter, VAS score was adopted for pain. Before treatment patient was not able to walk even 4 to 5 steps due to severe pain, was brought on stretcher and his SLR was 30° of right side. After 22 days of treatment he was able to walk up to 500 meters without any difficulty, SLR was changed to 60° and patient had got 80 % relief in pain. This case report showed that Ayurvedic protocol is potent and safe in the treatment of Gridhrasi.

scholarly journals Psychotropic and pain medication use in individuals with traumatic brain injury—a Swedish total population cohort study of 240 000 persons

2021 ◽  
Vol 92 (5) ◽  
pp. 519-527
Author(s):  
Yasmina Molero ◽  
David James Sharp ◽  
Brian Matthew D'Onofrio ◽  
Henrik Larsson ◽  
Seena Fazel
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Total Population ◽  
Medication Use ◽  
Population Based ◽  
Pain Medication ◽  
Short Term ◽  
Pain Medications ◽  
Before And After

ObjectiveTo examine psychotropic and pain medication use in a population-based cohort of individuals with traumatic brain injury (TBI), and compare them with controls from similar backgrounds.MethodsWe assessed Swedish nationwide registers to include all individuals diagnosed with incident TBI between 2006 and 2012 in hospitals or specialist outpatient care. Full siblings never diagnosed with TBI acted as controls. We examined dispensed prescriptions for psychotropic and pain medications for the 12 months before and after the TBI.ResultsWe identified 239 425 individuals with incident TBI, and 199 658 unaffected sibling controls. In the TBI cohort, 36.6% had collected at least one prescription for a psychotropic or pain medication in the 12 months before the TBI. In the 12 months after, medication use increased to 45.0%, an absolute rate increase of 8.4% (p<0.001). The largest post-TBI increases were found for opioids (from 16.3% to 21.6%, p<0.001), and non-opioid pain medications (from 20.3% to 26.6%, p<0.001). The majority of prescriptions were short-term; 20.6% of those prescribed opioids and 37.3% of those with benzodiazepines collected prescriptions for more than 6 months. Increased odds of any psychotropic or pain medication were associated with individuals before (OR: 1.62, 95% CI: 1.59 to 1.65), and after the TBI (OR: 2.30, 95% CI: 2.26 to 2.34) as compared with sibling controls, and ORs were consistently increased for all medication classes.ConclusionHigh rates of psychotropic and pain medications after a TBI suggest that medical follow-up should be routine and review medication use.

scholarly journals Studies on Short-term Rainfall Prediction Using Animation of Radar Images and Estimation of Average-Rainfall-Depth over a Watershed.

1997 ◽  
pp. 13-30
Author(s):  
Tadashi Yamada ◽  
Tadashi Hibino ◽  
Makoto Nakatsugawa ◽  
Mitsuaki Fujisawa ◽  
Hiroshi Morinaga
Keyword(s):  
Short Term ◽  
Rainfall Prediction ◽  
Radar Images ◽  
Rainfall Depth ◽  
Average Rainfall

Abstract P266: The Association Of Recent Age-specific Growth Of The > 65 Years Population With Heart Disease Mortality In The United States, 2005-2017

Circulation ◽  
2020 ◽  
Vol 141 (Suppl_1) ◽  
Author(s):  
Stephen Sidney ◽  
Sadiya S Khan ◽  
Yariv Gerber ◽  
Donald M Lloyd-jones ◽  
Alan S Go ◽  
...  
Keyword(s):  
Heart Disease ◽  
Mortality Rate ◽  
Population Growth ◽  
Total Population ◽  
Age Groups ◽  
The United States ◽  
Population Increase ◽  
Age Group ◽  
Specific Population ◽  
Time Periods

Introduction: In 2011, the number of deaths with an underlying cause of heart disease (HD) reached its lowest level in 56 years. However, there has subsequently been a steady increase in the annual number of total HD deaths, owing to a rapid increase (23%) in the size of the population ≥65 years of age in the U.S. To understand these trends, we sought to characterize differences between 2005-2011 and 2011-2017 in population and mortality by age subgroups among those ≥65 years. Methods: We determined age-specific population size, HD mortality rate, and absolute number of HD deaths in the ≥65 age group for the time periods 2005-2011 and 2011-2017, as well as for the <65 years age group, using the CDC WONDER online data set. Results: Age-specific population growth was greatest among those 65-74 years between 2005-2011 and 2011-2017, representing 76% of the total population growth among those ≥65 years old in both time periods (Table) and 51% of the growth for the entire population from 2011-2017. From 2005-2011, decreases in the mortality rate of 20% or greater in each of the age subgroups (65-74, 75-84, 85+) resulted in a decline in the number of total HD deaths in each of the age groups in spite of substantial population increases in the 65-74 and 85+ age groups. However, subsequent changes in the age-specific mortality rate among those ≥65 years were lower than population increases from 2011-2017, resulting in an increased number of total HD deaths in all > 65 years age subgroups. This was most notable among those age 65-74 years in whom the 32% population increase with a 1.5% decline in the mortality rate resulted in a 30% increase in the number of HD deaths, representing 61.3% of the increase in number of HD deaths in the 65+ years age group and 53% of the increase of HD deaths in all age groups from 2011-2017. Conclusions: The rapid growth of the 65-74 years age group (baby boomers) accounts for most of the population growth in the ≥65 years age group and more than half the increase in both total population growth and the total number of HD deaths from 2011-2017.

Managing for rainfall variability: impacts of grazing strategies on perennial grass dynamics in a dry tropical savanna

2011 ◽  
Vol 33 (2) ◽  
pp. 209 ◽  
Author(s):  
D. M. Orr ◽  
P. J. O'Reagain
Keyword(s):  
Carrying Capacity ◽  
Rainfall Variability ◽  
Perennial Grasses ◽  
Heteropogon Contortus ◽  
Heavy Grazing ◽  
Average Rainfall ◽  
Sustainable Grazing ◽  
Grazing Strategies ◽  
The Impact

Rainfall variability remains a major challenge to sustainable grazing management in northern Australia with perennial grasses the key to the stability of the resources that maintain a sustainable grazing industry. This paper describes the dynamics of five perennial grasses – Bothriochloa ewartiana (Domin) C.E. Hubb., Chrysopogon fallax S.T. Blake, Aristida spp., Panicum effusum R. Br. and Heteropogon contortus (L.) P. Beauv. ex Roem. & Schult. in relation to three grazing strategies – moderate stocking at long-term carrying capacity, heavy stocking and rotational wet season spelling. The research was conducted in permanent quadrats on the predominant land type in an extensive grazing study in an Aristida-Bothriochloa pasture in north Australia between 1998 and 2010. Summer rainfall was above average for two periods – 1998 – 2001 and 2008 – 2010 with drought and below-average rainfall from 2002 to 2007. Low rainfall affected the dynamics of all grasses by reducing survival and basal area through its effect on plant size; this impact was most noticeable for the shorter-lived Aristida spp., P. effusum and H. contortus. The impact of grazing was greatest on the long-lived B. ewartiana and C. fallax; this effect was accentuated by the 2002–07 drought. Heavy grazing during this period further reduced the survival and size of B. ewartiana in comparison with the moderate stocking and rotational spell treatments. In contrast, the survival of C. fallax was reduced in the moderate stocking and rotational spelling treatment during drought, relative to that under heavy grazing. The density of B. ewartiana declined even under moderate grazing and despite two sequences of above-average rainfall because seedling recruitment failed to offset mature plant death. Results from this study emphasised the importance of maintaining the existing populations of key long-lived species such as B. ewartiana through good management. These results also supported the overall findings from the grazing study indicating that stocking at the long-term carrying capacity is sustainable in managing for climate variability.

scholarly journals Carrying Capacity of a Population Diffusing in a Heterogeneous Environment

Mathematics ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 49 ◽  
Author(s):  
D.L. DeAngelis ◽  
Bo Zhang ◽  
Wei-Ming Ni ◽  
Yuanshi Wang
Keyword(s):  
Population Size ◽  
Carrying Capacity ◽  
Heterogeneous System ◽  
Total Population ◽  
Reaction Diffusion ◽  
Maximum Growth ◽  
Reaction Diffusion Equations ◽  
Logistic Growth ◽  
Chemostat Model ◽  
Total Population Size

The carrying capacity of the environment for a population is one of the key concepts in ecology and it is incorporated in the growth term of reaction-diffusion equations describing populations in space. Analysis of reaction-diffusion models of populations in heterogeneous space have shown that, when the maximum growth rate and carrying capacity in a logistic growth function vary in space, conditions exist for which the total population size at equilibrium (i) exceeds the total population that which would occur in the absence of diffusion and (ii) exceeds that which would occur if the system were homogeneous and the total carrying capacity, computed as the integral over the local carrying capacities, was the same in the heterogeneous and homogeneous cases. We review here work over the past few years that has explained these apparently counter-intuitive results in terms of the way input of energy or another limiting resource (e.g., a nutrient) varies across the system. We report on both mathematical analysis and laboratory experiments confirming that total population size in a heterogeneous system with diffusion can exceed that in the system without diffusion. We further report, however, that when the resource of the population in question is explicitly modeled as a coupled variable, as in a reaction-diffusion chemostat model rather than a model with logistic growth, the total population in the heterogeneous system with diffusion cannot exceed the total population size in the corresponding homogeneous system in which the total carrying capacities are the same.

Comparison of Visual Survey and Mark–Recapture Population Estimates of a Benthic Fish in Hawaii

2016 ◽  
Vol 145 (4) ◽  
pp. 878-887 ◽  
Author(s):  
Ernie F. Hain ◽  
Bradley A. Lamphere ◽  
Michael J. Blum ◽  
Peter B. McIntyre ◽  
Stacy A.C. Nelson ◽  
...  
Keyword(s):  
Population Estimates ◽  
Benthic Fish ◽  
Mark Recapture ◽  
Visual Survey

scholarly journals Activation of the tryptophan/serotonin pathway is associated with severity and predicts outcomes in pneumonia: results of a long-term cohort study

2017 ◽  
Vol 55 (7) ◽  
Author(s):  
Marc A. Meier ◽  
Manuel Ottiger ◽  
Alaadin Vögeli ◽  
Christian Steuer ◽  
Luca Bernasconi ◽  
...  
Keyword(s):  
Adverse Outcome ◽  
Multivariate Regression Analysis ◽  
Multicenter Trial ◽  
Immune Defense ◽  
Strong Positive Correlation ◽  
C Reactive Protein ◽  
Short Term ◽  
Reactive Protein ◽  
Positive Effects ◽  
Severity Scores

AbstractBackground:As part of the immune defense during infection, an increase in enzyme activity of indoleamine 2,3-dioxygenase (IDO) leads to a breakdown of tryptophan to kynurenine. In previous animal studies, therapeutic antagonism of IDO resulted in reduced sepsis mortality. We investigated the prognostic ability of tryptophan, serotonin, kynurenine and IDO (represented by the ratio of kynurenine/tryptophan) to predict adverse clinical outcomes in patients with community-acquired pneumonia (CAP).Methods:We measured tryptophan, serotonin and kynurenine on admission plasma samples from CAP patients included in a previous multicenter trial by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We studied their association with inflammation (C-reactive protein), infection (procalcitonin) and clinical outcome.Results:Mortality in the 268 included patients was 45% within 6 years of follow-up. IDO and kynurenine showed a strong positive correlation with markers of infection (procalcitonin) and inflammation (C-reactive protein) as well as sepsis and CAP severity scores. Tryptophan showed similar, but negative correlations. In a multivariate regression analysis adjusted for age and comorbidities, higher IDO activity and lower tryptophan levels were strongly associated with short-term adverse outcome defined as death and/or ICU admission within 30 days with adjusted odds ratios of 9.1 [95% confidence interval (CI) 1.4–59.5, p=0.021] and 0.11 (95% CI 0.02–0.70, p=0.021). Multivariate analysis did not reveal significant associations for kynurenine and serotonin.Conclusions:In hospitalized CAP patients, higher IDO activity and lower tryptophan levels independently predicted disease severity and short-term adverse outcome. Whether therapeutic modulation of IDO has positive effects on outcome needs further investigation.

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