Nasty, Brutish, but Not Necessarily Short: A Reconsideration of the Statistical Methods Used to Calculate Age at Death from Adult Human Skeletal and Dental Age Indicators

1999 ◽  
Vol 64 (1) ◽  
pp. 55-70 ◽  
Author(s):  
Robert G. Aykroyd ◽  
David Lucy ◽  
A. Mark Pollard ◽  
Charlotte A. Roberts
Keyword(s):  
Bayesian Approach ◽  
Older Individuals ◽  
Dental Age ◽  
Average Difference ◽  
Age At Death ◽  
Bayesian Approaches ◽  
Interval Width ◽  
Confidence Interval Width ◽  
Better Than ◽  
Age Estimates

It is generally assumed that life expectancy in antiquity was considerably shorter than it is now. In the limited number of cases where skeletal or dental age-at-death estimates have been made on adults for whom there are other reliable indications of age, there appears to be a clear systematic trend towards overestimating the age of young adults, and underestimating that of older individuals. We show that this might be a result of the use of regression-based techniques of analysis for converting age indicators into estimated ages. Whilst acknowledging the limitations of most age-at-death indicators in the higher age categories, we show that a Bayesian approach to converting age indicators into estimated age can reduce this trend of underestimation at the older end. We also show that such a Bayesian approach can always do better than regression-based methods in terms of giving a smaller average difference between predicted age and known age, and a smaller average 95-percent confidence interval width of the estimate. Given these observations, we suggest that Bayesian approaches to converting age indicators into age estimates deserve further investigation. In view of the generality and flexibility of the approach, we also suggest that similar algorithms may have a much wider application.

scholarly journals Molecular clocks in ancient proteins: Do they reflect the age at death even after millennia?

2021 ◽  
Author(s):  
Nina Sophia Mahlke ◽  
Silvia Renhart ◽  
Dorothea Talaa ◽  
Alexandra Reckert ◽  
Stefanie Ritz-Timme
Keyword(s):  
Protein Degradation ◽  
Forensic Medicine ◽  
Molecular Clocks ◽  
Post Mortem ◽  
Age At Death ◽  
Morphological Examination ◽  
Dental Tissues ◽  
Ancient Proteins ◽  
Age Estimates ◽  
Age At Death Estimation

AbstractAge at death estimation in cases of human skeletal finds is an important task in forensic medicine as well as in anthropology. In forensic medicine, methods based on “molecular clocks” in dental tissues and bone play an increasing role. The question, whether these methods are applicable also in cases with post-depositional intervals far beyond the forensically relevant period, was investigated for two “protein clocks”, the accumulation of D-aspartic acid (D-Asp) and the accumulation of pentosidine (Pen) in dentine. Eight teeth of skeletons from different burial sites in Austria and with post-depositional intervals between c. 1216 and c. 8775 years were analysed. The results of age at death estimation based on D-Asp and Pen in dentine were compared to that derived from a classical morphological examination. Age at death estimation based on D-Asp resulted consistently in false high values. This finding can be explained by a post-mortem accumulation of D-Asp that may be enhanced by protein degradation. In contrast, the Pen-based age estimates fitted well with the morphological age diagnoses. The described effect of post-mortem protein degradation is negligible in forensically relevant time horizons, but not for post-depositional intervals of thousands of years. That means that the “D-Asp clock” loses its functionality with increasing post-depositional intervals, whereas Pen seems to be very stable. The “Pen-clock” may have the potential to become an interesting supplement to the existing repertoire of methods even in cases with extremely long post-depositional intervals. Further investigations have to test this hypothesis.

scholarly journals Approaches to the talent management agenda in forestry companies

2016 ◽  
Vol 62 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Lucie Vnoučková ◽  
Hana Urbancová ◽  
Helena Smolová
Keyword(s):  
Talent Management ◽  
Average Difference ◽  
Professional Literature ◽  
One Dimensional ◽  
Primary Sector ◽  
Developmental Conditions ◽  
Development And Management ◽  
Multidimensional Statistics ◽  
Negative Phenomena ◽  
Better Than

Abstract Professional literature and practice started to focus intensively on the field of talent management. A lack of talented individuals occurred in all sectors worldwide. The war for talents has not faded out, on the contrary, it has been intensifying. The aim of the paper is therefore to analyse the perception of opportunities for development and management of talents in forestry and to specify characteristics of employee/ talent support perception in surveyed companies. The analysis is based on a primary survey conducted in 101 forestry companies. The data were obtained through surveys in which one manager and one employee represented a single company. One-dimensional and multidimensional statistics were used to evaluate the data. The results showed that employees perceived developmental conditions in companies more positively than what was stated by managers and company representatives. The average difference in the perception was 8.5%; employees perceived the conditions better than company representatives. When negative phenomena were analysed, the perception was quite opposite. The average difference was 9.5%. The limit of the paper is the narrow focus on primary sector companies. The results may help surveyed companies in the primary sector to encourage managers and employees to participate in developmental programmes as their own initiative and willingness to take part in education and developmental activities was found.

scholarly journals On Older Listeners' Ability to Perceive Dynamic Pitch

2016 ◽  
Vol 59 (3) ◽  
pp. 572-582 ◽  
Author(s):  
Jing Shen ◽  
Richard Wright ◽  
Pamela E. Souza
Keyword(s):  
Speech Recognition ◽  
Interindividual Variability ◽  
Pitch Perception ◽  
Natural Speech ◽  
Pitch Contour ◽  
Older Individuals ◽  
Pitch Contours ◽  
Pitch Patterns ◽  
Better Than

PurposeNatural speech comes with variation in pitch, which serves as an important cue for speech recognition. The present study investigated older listeners' dynamic pitch perception with a focus on interindividual variability. In particular, we asked whether some of the older listeners' inability to perceive dynamic pitch stems from the higher susceptibility to the interference from formant changes.MethodA total of 22 older listeners and 21 younger controls with at least near-typical hearing were tested on dynamic pitch identification and discrimination tasks using synthetic monophthong and diphthong vowels.ResultsThe older listeners' ability to detect changes in pitch varied substantially, even when musical and linguistic experiences were controlled. The influence of formant patterns on dynamic pitch perception was evident in both groups of listeners. Overall, strong pitch contours (i.e., more dynamic) were perceived better than weak pitch contours (i.e., more monotonic), particularly with rising pitch patterns.ConclusionsThe findings are in accordance with the literature demonstrating some older individuals' difficulty perceiving dynamic pitch cues in speech. Moreover, they suggest that this problem may be prominent when the dynamic pitch is carried by natural speech and when the pitch contour is not strong.

scholarly journals SARS-CoV-2 transmission across age groups in France and implications for control

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cécile Tran Kiem ◽  
Paolo Bosetti ◽  
Juliette Paireau ◽  
Pascal Crépey ◽  
Henrik Salje ◽  
...  
Keyword(s):  
Young Adults ◽  
Age Groups ◽  
Deep Understanding ◽  
Transmission Dynamics ◽  
Age Group ◽  
Older Individuals ◽  
Targeted Intervention ◽  
Social Distancing ◽  
Intervention Measures ◽  
Better Than

AbstractThe shielding of older individuals has been proposed to limit COVID-19 hospitalizations while relaxing general social distancing in the absence of vaccines. Evaluating such approaches requires a deep understanding of transmission dynamics across ages. Here, we use detailed age-specific case and hospitalization data to model the rebound in the French epidemic in summer 2020, characterize age-specific transmission dynamics and critically evaluate different age-targeted intervention measures in the absence of vaccines. We find that while the rebound started in young adults, it reached individuals aged ≥80 y.o. after 4 weeks, despite substantial contact reductions, indicating substantial transmission flows across ages. We derive the contribution of each age group to transmission. While shielding older individuals reduces mortality, it is insufficient to allow major relaxations of social distancing. When the epidemic remains manageable (R close to 1), targeting those most contributing to transmission is better than shielding at-risk individuals. Pandemic control requires an effort from all age groups.

scholarly journals Perbandingan Latihan Pliometrik Depth Jump dan Jump To Box Power Terhadap Otot Tungkai dalam Smash Permainan Bola Voli

2017 ◽  
Vol 3 (1) ◽  
pp. 32-39
Author(s):  
Deswita Suprianti ◽  
Zenda Paripurna
Keyword(s):  
Extracurricular Activities ◽  
Muscle Power ◽  
Vertical Jump ◽  
Sampling Technique ◽  
Average Difference ◽  
Plyometric Training ◽  
Group Design ◽  
Leg Muscle ◽  
Leg Muscle Power ◽  
Better Than

This study aims to find out better plyometric exercises between depth jump and jump to box plyometrics exercises on leg muscle power in volleyball smash games in Mts Salafiah extracurricular. This research uses experimental methods with the design of "pretest-posttest one group design". The population in this study were volleyball students in Mts Salafiah extracurricular totaling 30 students. Samples taken from the results of the sampling technique that is purposive sampling, with criteria namely; (1) actively participating in extracurricular activities in Mts Salafiah, (2) registered as extracurricular participants in Mts Salafiah, (3) willing to take part in the training during the research. Based on these criteria, there were 20 students who met them. The instrument used for the jump height test is the vertical jump. Data analysis using t test. The results of the analysis showed that: (1) There was an effect of depth jump plyometric training on leg muscle power in volleyball smash games in Mts Salafiah extracurricular, with t count 3.405> t table 2.23, and significance value 0.008 <0.05, increase in the average difference in value 5.40 cm. (2) There is an effect of jump to box plyometric training on leg muscle power in volleyball smash in Mts Salafiah extracurricular, with t count value 2. 945> t table 2.23, and significance value 0.016 <0.05, increase in mean difference of 3.70 cm. (3) Jump to box plyometric training is better than depth jump plyometric training on leg muscle power in volleyball smash games in Mts Salafiah extracurricular, with an average difference of 10.50 cm

scholarly journals Presbyopia in old wild bonobos (Pan paniscus)

2016 ◽  
Author(s):  
Heungjin Ryu ◽  
Kirsty E. Graham ◽  
Tetsuya Sakamaki ◽  
Takeshi Furuichi
Keyword(s):  
Pan Troglodytes ◽  
Democratic Republic ◽  
Pan Paniscus ◽  
Democratic Republic Of Congo ◽  
Older Individuals ◽  
Human Beings ◽  
People First ◽  
Genome Level ◽  
Over 40 Years ◽  
Age Estimates

Presbyopia, or long-sightedness, is one of the signs of senescence in humans. Many people first recognize it when they approach 40-years-old, though presbyopia progresses gradually with age. Not surprisingly, presbyopia has been reported in old, wild chimpanzees (Pan troglodytes) at Bossou (Guinea) and Mahale (Tanzania). Bonobos are one of our closest living relatives (98.7% identical in genome level) and like us have long development periods and long longevity. We therefore expected to find presbyopia in bonobos. Here we report evidence of presbyopia in wild bonobos at Wamba, Democratic Republic of Congo, during grooming interactions. We used an interchangeable-lens camera to make precise measurements of ear dimensions for each individual, which we then used to determine grooming distance. Age estimates for older individuals were taken when the group was first identified in the late 1970s to early 1980s. We found that grooming distance increases with age. All four bonobos that showed symptoms of presbyopia, i.e. long grooming distance, were estimated to be over 40 years old in 2015. We confirmed that when grooming others, the 4 older individuals kept significantly longer distance between their hands and eyes than did younger individuals. This result indicates that bonobos begin to experience presbyopia in their 40s as do human beings.

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