scholarly journals Stalagmite evidence for Early Holocene multidecadal hydroclimate variability in Ethiopia

2021 ◽  
Author(s):  
Asfawossen Asrat ◽  
Andy Baker ◽  
Wuhui Duan ◽  
Melanie Leng ◽  
Ian Boomer ◽  
...  
Keyword(s):  
Growth Rate ◽  
Trace Element ◽  
Early Holocene ◽  
Central China ◽  
Annual Rainfall ◽  
Annual Growth Rate ◽  
Primary Control ◽  
Karst Hydrology ◽  
Hydroclimate Variability ◽  
Non Equilibrium

A multiproxy oxygen and carbon isotope (d13C and d18O), growth rate and trace element stalagmite paleoenvironmental record is presented for the Early Holocene from Achere Cave, Ethiopia. The annually laminated stalagmite grew from 10.6 to 10.4 ka, and from 9.7 to 9.0 ka with a short hiatus at ~9.25 ka. Using oxygen and carbon isotopic, and cave monitoring data, we demonstrate that the stalagmite deposition is out of isotopic equilibrium, yet trace element and isotope geochemistry is sensitive to hydroclimate variability. Variogram analysis of annual growth rate data suggests that this proxy can only contain hydroclimate information over less than 28-year timescales. Statistically significant and coherent spectral frequencies in d13C and d18O are observed at 15-25 and 19-23 years respectively. Combined with compelling evidence for deposition out of isotope equilibrium, the observed ~1 ‰ amplitude variability in stalagmite d18O is likely forced by non-equilibrium deposition, likely due to kinetic effects during the progressive degassing of CO2 from the water film during stalagmite formation. These frequencies are similar to the periodicity reported for Holocene stalagmite records from Ethiopian caves, suggesting that multidecadal variability in stalagmite d18O is typical. We hypothesise that a hydroclimate forcing, such as runs of one or more years of low annual rainfall, is likely to be the primary control on the extent of the partial evaporation of soil and shallow epikarst water, which is subsequently modulated by karst hydrology, and the extent of in-cave non-equilibrium stalagmite deposition. Combined with possible recharge-biases in drip water d18O, modulated by karst hydrology, these processes can generate multidecadal d18O variability which can operate with opposite signs. Comparison of Early Holocene d18O stalagmite records from the monsoon regions of Ethiopia, Oman and central China show different multi-decadal d18O signals, implying regional difference in climate forcing. Seismic activities due to the active tectonics in the region control the frequency of growth gaps (hiatuses) by changing the water flow paths to the stalagmite.

scholarly journals Rapid population growth in an elephant Loxodonta africana population recovering from poaching in Tarangire National Park, Tanzania

Oryx ◽  
2010 ◽  
Vol 44 (2) ◽  
pp. 205-212 ◽  
Author(s):  
Charles A. H. Foley ◽  
Lisa J. Faust
Keyword(s):  
Growth Rate ◽  
National Park ◽  
Loxodonta Africana ◽  
Annual Rainfall ◽  
Annual Growth Rate ◽  
African Elephants ◽  
Tarangire National Park ◽  
Maximal Growth Rate ◽  
The Right ◽  
Annual Mortality

AbstractWe studied the demography of a subpopulation of African elephants Loxodonta africana in Tarangire National Park, Tanzania, from 1993 to 2005. The Tarangire elephants had been affected by heavy poaching prior to 1993. We monitored 668 individually known elephants in 27 family groups. The population increased from 226 to 498 individuals, with mean group size increasing from 8.4 to 18.3. The average annual growth rate was 7.1% (range 2.0–16.9%). This approaches the maximal growth rate for African elephants, with corresponding minimal values for demographic parameters. The mean interbirth interval was 3.3 years, mean age of first reproduction 11.1 years, average annual mortality of elephants younger than 8 years 3%, and average annual mortality of adult females 1%. Probability of conceiving was positively correlated with annual rainfall. No significant density-dependent effects were recorded. Rapid growth was aided by high rainfall, low population density and release from the stresses of poaching. These results demonstrate that elephant populations are capable of rapid population increases for extended periods of time given the right ecological and social conditions. This has consequences for elephant conservation and management.

Reviewing Progresses in Technologies by their Annual Growth Rate Changes

2020 ◽  
Vol 74 (4) ◽  
pp. 365-371
Author(s):  
Kiyoaki Iida
Keyword(s):  
Growth Rate ◽  
Annual Growth ◽  
Annual Growth Rate

Ageing Saudi Population in the Facebook Era

2018 ◽  
Author(s):  
Asharaf Abdul Salam
Keyword(s):  
Growth Rate ◽  
Saudi Arabia ◽  
Population Ageing ◽  
Annual Growth ◽  
Annual Growth Rate ◽  
Saudi Population ◽  
Aged Population ◽  
Facebook Usage

<p>Data pertaining to 1974, 1992, 2004 and 2010 Censuses in Saudi Arabia was collected. Some reviews and literature on population ageing in Saudi Arabia as well as Facebook usage obtained. Statistics pertaining to Saudi population was utilized.</p> <p>Aged population in 2010 estimated by assuming the annual growth rate of 1974-2004.</p>

scholarly journals Association between triglyceride-glucose index and risk of arterial stiffness: a cohort study

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Shouling Wu ◽  
Luli Xu ◽  
Mingyang Wu ◽  
Shuohua Chen ◽  
Youjie Wang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Linear Regression ◽  
Arterial Stiffness ◽  
Multivariate Linear Regression ◽  
Annual Growth ◽  
Annual Growth Rate ◽  
Cross Sectional ◽  
Tyg Index ◽  
Longitudinal Association ◽  
The Cross

Abstract Background Triglyceride–glucose (TyG) index, a simple surrogate marker of insulin resistance, has been reported to be associated with arterial stiffness. However, previous studies were limited by the cross-sectional design. The purpose of this study was to explore the longitudinal association between TyG index and progression of arterial stiffness. Methods A total of 6028 participants were derived from the Kailuan study. TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Arterial stiffness was measured using brachial-ankle pulse wave velocity (baPWV). Arterial stiffness progression was assessed by the annual growth rate of repeatedly measured baPWV. Multivariate linear regression models were used to estimate the cross-sectional association of TyG index with baPWV, and Cox proportional hazard models were used to investigate the longitudinal association between TyG index and the risk of arterial stiffness. Results Multivariate linear regression analyses showed that each one unit increase in the TyG index was associated with a 39 cm/s increment (95%CI, 29–48 cm/s, P < 0.001) in baseline baPWV and a 0.29 percent/year increment (95%CI, 0.17–0.42 percent/year, P < 0.001) in the annual growth rate of baPWV. During 26,839 person-years of follow-up, there were 883 incident cases with arterial stiffness. Participants in the highest quartile of TyG index had a 58% higher risk of arterial stiffness (HR, 1.58; 95%CI, 1.25–2.01, P < 0.001), as compared with those in the lowest quartile of TyG index. Additionally, restricted cubic spline analysis showed a significant dose–response relationship between TyG index and the risk of arterial stiffness (P non-linearity = 0.005). Conclusion Participants with a higher TyG index were more likely to have a higher risk of arterial stiffness. Subjects with a higher TyG index should be aware of the following risk of arterial stiffness progression, so as to establish lifestyle changes at an early stage.

scholarly journals Estimation of the feeding record of pregnant Antarctic minke whales (Balaenoptera bonaerensis) using carbon and nitrogen stable isotope analysis of baleen plates

Polar Biology ◽  
2021 ◽  
Vol 44 (3) ◽  
pp. 621-629
Author(s):  
Mayuka Uchida ◽  
Ippei Suzuki ◽  
Keizo Ito ◽  
Mayumi Ishizuka ◽  
Yoshinori Ikenaka ◽  
...  
Keyword(s):  
Growth Rate ◽  
Stable Isotope ◽  
Antarctic Krill ◽  
Isotope Analysis ◽  
Stomach Contents ◽  
Annual Growth Rate ◽  
Pleuragramma Antarcticum ◽  
Minke Whales ◽  
Balaenoptera Bonaerensis ◽  
The Antarctic

AbstractAntarctic minke whales (Balaenoptera bonaerensis) are migratory capital breeders that experience intensive summer feeding on Antarctic krill (Euphausia superba) in the Southern Ocean and winter breeding at lower latitudes, but their prey outside of the Antarctic is unknown. Stable isotope analyses were conducted on δ13C and δ15N from the baleen plates of ten pregnant Antarctic minke whales to understand the growth rate of the baleen plate and their diet in lower latitudes. Two to three oscillations along the length of the edge of the baleen plate were observed in δ15N, and the annual growth rate was estimated to be 75.2 ± 20.4 mm, with a small amplitude (0.97 ± 0.21 ‰). Bayesian stable isotope mixing models were used to understand the dominant prey that contributed to the isotopic component of the baleen plate using Antarctic krill from the stomach contents and reported values of Antarctic coastal krill (Euphausia crystallorophias), Antarctic silver fish (Pleuragramma antarcticum), Australian krill spp., and Australian pelagic fish spp.. The models showed that the diet composition of the most recent three records from the base of the baleen plates (model 1) and the highest δ15N values in each baleen plate (model 2) were predominantly Antarctic krill, with a contribution rate of approximately 80%. The rates were approximately 10% for Antarctic coastal krill and less than 2.0% for the two Australian prey groups in both models. These results suggest that pregnant Antarctic minke whales did not feed on enough prey outside of the Antarctic to change the stable isotope values in their baleen plates.

Abstract TP80: Incidence And Risk Factors For The Growth And Rupture Of Unruptured Cerebral Aneurysms. Results Of Annual Radiologic Follow Up Study.

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Katsumi Matsumoto ◽  
Kouichirou Tsuruzono ◽  
Manabu Sasaki ◽  
Noriyasu Yoshimura ◽  
Toshiki Yoshimine ◽  
...  
Keyword(s):  
Growth Rate ◽  
Cerebral Aneurysms ◽  
Aneurysm Rupture ◽  
Annual Growth ◽  
Annual Growth Rate ◽  
Rupture Rate ◽  
Follow Up Study ◽  
Factors Influencing ◽  
Unruptured Cerebral Aneurysms

Background: The recent trend of the treatment of unruptured cerebral aneurysms(UIAs) is going to be conservative. Their natural history of rupture and growth is still unkown. We present the results of annual radiological follow-up study in UIAs. Method: In recent 12 years, we have found 121patients with 148 unruptured cerebral aneurysms were followed annually using 3D-CTA or MRA. Mean follow-up period was 5.5 year. Several factors influencing rupture or growth were statistically examined. Results: Among 121 patients, 9 ruptured and 11 showed growth of UIAs. Annual rupture rate was 1.3% per year and annual growth rate was 1.6% per year. Aneurysm size was the sole factor influencing rupture(P<0.001), whereas female sex and multiplicity were major factors influencing aneurysm growth(P<0.05). Under size 3mm, annual growth rate was 3.0% whereas annual rupture rate was 0.7%. In 4-6mm, growth rate was 1.6% and rupture rate was 1.6%. In 7-9mm, growth rate was 0 and rupture rate was 5.8%. In over 10mm, growth rate was 2.9% and rupture rate was 11.6%. Within 1 year, rupture occurred in 4 cases, and growth was found in 1 case. Conclusions: By annual radiological examination, growth of UIAs was noted more frequently than aneurysm rupture. Especially UIAs under 3mm, growth was 4 times higher than rupture, radiological follow up is effective for aneurysm rupture. Within 1 year, initially found UIAs should be carefully followed in a short interval.

scholarly journals BRITISH JOURNAL OF CANCER: A SCIENTOMETRIC STUDY

2017 ◽  
Vol 4 (3) ◽  
pp. 98-102
Author(s):  
Senthilkumar R ◽  
Muthukrishnan M
Keyword(s):  
Growth Rate ◽  
British Journal ◽  
Research Productivity ◽  
Scientific Publication ◽  
Annual Growth Rate ◽  
Document Type ◽  
Author Productivity ◽  
Research Document ◽  
Scientometric Study ◽  
Rate Research

The present study examined scientific publication research productivity in British journal of cancer for a period of selected 11 years between 2005 and 2015.Making  use of various scientometric indicators likethe annual growth rate, research document type, author productivity, Degree of collaboration, country wise Distribution, Institution wise distributionwas also used to analyze the data and interpretation. The study reveals that total 6818records were published in the 264 issues of the journal.

scholarly journals Epidemiological Aspects of Overweight and Obesity among the Adult Population of the Voronezh Region

2019 ◽  
Vol 18 (1) ◽  
pp. 82-87
Author(s):  
N. V. Gabbasova ◽  
N. V. Dzen
Keyword(s):  
Growth Rate ◽  
Eating Behavior ◽  
Adult Population ◽  
Overweight And Obesity ◽  
Comparative Assessment ◽  
Average Annual Growth Rate ◽  
Annual Growth Rate ◽  
Ideal Weight ◽  
Voronezh Region ◽  
Prevalence Of Obesity

Relevance Obesity has a major impact on the health and well-being of the population, and the prevention of overweight and obesity is a public health priority in many countries around the world.Purpose: was to study the prevalence of obesity among the adult population of the Voronezh region for the period 1996 – 2017, a comparative assessment of the structure of eating behavior in people with normal weight and overweight/obesity.Methods. The research material was data the annual form No. 12 of Rosstat for 1996 through 2017. In order to study eating disorders, 150 people aged from 20 to 61 years were surveyed using the Dutch questionnaire. The main types of eating behavior among the respondents were determined. Ideal weight was calculated by Brock's field formula (1891), the upper limit of normal body weight was considered ideal weight plus 15% ideal weight. Statistical data processing was performed using Microsoft Excel 2007.Results. The study on the prevalence of obesity was conducted among the adult population of the Voronezh region for the period 1996-2017. The Prevalence of obesity over the period studied has increased by 8 times, the average annual growth rate over the last 4 years was 30,04%. The study of the types of food behavior in respondents with normal and overweight / obesity showed that in most cases the respondents observed pathological types (most often mixed and external). A comparative assessment of the types of eating behavior did not show any significant differences between the groups.Conclusions. The increase in the prevalence of obesity, the high average annual growth rate indicates the increased impact of risk factors on the formation of obesity and the ineffectiveness of the strategy and tactics of dealing with this pathology. The absence of significant differences in the structure of eating behavior does not allow us to consider it a risk factor for obesity. 

scholarly journals Biofuel plant species and the contribution of genetic improvement

2011 ◽  
Vol 11 (spe) ◽  
pp. 16-26 ◽  
Author(s):  
Luiz Antônio dos Santos Dias
Keyword(s):  
Growth Rate ◽  
Plant Species ◽  
Genetic Improvement ◽  
Raw Materials ◽  
Environmental Security ◽  
Biodiesel Production ◽  
Special Focus ◽  
Annual Growth Rate ◽  
Breeding Programs ◽  
Improvement Programs

The paper analyses the puzzle of the food-energy-environmental security interaction, to which biofuels are part of the solution. It presents and discusses the contribution of genetic improvement to biofuels, with regard to the production of raw materials (oil and ethanol-producing plant species) and designs perspectives, opportunities, risks and challenges, with a special focus on the Brazilian scene. Bioethanol is a consolidated biofuel owing largely to the sugarcane breeding programs. These programs released 111 sugarcane cultivars and were responsible for a 20.8 % gain in productivity of bioethanol (in m³ ha-1) between 2000 and 2009. The program of Brazilian biodiesel production, initiated in 2005, had an annual growth rate of 10 % and the country is already the world's fourth largest producer. However, the contribution of breeding to biodiesel production is still modest, due to the lack of specific improvement programs for oil.

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