scholarly journals Direct dating of Pleistocene stegodon from Timor Island, East Nusa Tenggara

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1788 ◽  
Author(s):  
Julien Louys ◽  
Gilbert J. Price ◽  
Sue O’Connor
Keyword(s):  
Environmental Changes ◽  
Southeast Asian ◽  
Oceanic Islands ◽  
Current Data ◽  
Island Population ◽  
Modern Humans ◽  
Uranium Series ◽  
Uranium Series Dating

Stegodons are a commonly recovered extinct proboscidean (elephants and allies) from the Pleistocene record of Southeast Asian oceanic islands. Estimates on when stegodons arrived on individual islands and the timings of their extinctions are poorly constrained due to few reported direct geochronological analyses of their remains. Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor. The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island. On the basis of current data, we find no evidence for significant environmental changes or the presence of modern humans in the region during that time. Thus, we do not consider either of these factors to have contributed significantly to their extinction. In the absence of these, we propose that their extinction was possibly the result of long-term demographic and genetic declines associated with an isolated island population.

Three islands and an archipelago: reciprocal interactions between humans and island ecosystems in Polynesia

2007 ◽  
Vol 98 (1) ◽  
pp. 85-99 ◽  
Author(s):  
Patrick V. Kirch
Keyword(s):  
Environmental Changes ◽  
Oceanic Islands ◽  
Model Systems ◽  
Comparative Approach ◽  
Human Populations ◽  
Island Ecosystems ◽  
Human Environment ◽  
Reciprocal Interactions ◽  
Sociopolitical Structures

ABSTRACTOceanic islands offer outstanding ‘model systems' for investigating long-term dynamics between human populations and their ecosystems. Whilst the state factors involved in human-environment dynamics on islands are often simpler than on continents, the same essential processes are involved. This paper applies a comparative approach to understanding the reciprocal interactions between a set of four Polynesian island cases (Tikopia, Mangaia, Mangareva, Hawaiian Islands), over time scales of between one and three thousand years (kyr). In all cases, the island ecosystems were colonised by Polynesian populations derived from the same ancestral culture, with similar socioeconomic patterns. However, the ecosystems vary significantly in scale, geologic age, and other characteristics. Comparing the historical trajectories of these human–environment dynamics, as revealed by archaeological and palaeoecological study, provides insights into the relative impact of humans on pristine island ecosystems, the influence of environment on ecosystem vulnerability, and the ways in which societies have modified their economies, sociopolitical structures, and other aspects of culture in response to long-term environmental changes.

scholarly journals Response to Comment on “The earliest modern humans outside Africa”

Science ◽  
2018 ◽  
Vol 362 (6413) ◽  
pp. eaat8964 ◽  
Author(s):  
Israel Hershkovitz ◽  
Mathieu Duval ◽  
Rainer Grün ◽  
Norbert Mercier ◽  
Helene Valladas ◽  
...  
Keyword(s):  
Homo Sapiens ◽  
Modern Human ◽  
Modern Humans ◽  
Uranium Series ◽  
Uranium Series Dating ◽  
Dating Methods ◽  
Out Of Africa ◽  
Numerical Dating

Our original claim, based on three independent numerical dating methods, of an age of ~185,000 years for the Misliya-1 modern human hemi-maxilla from Mount Carmel, Israel, is little affected by discounting uranium-series dating of adhering crusts. It confirms a much earlier out-of-Africa Homo sapiens expansion than previously suggested by the considerably younger (90,000 to 120,000 years) Skhul/Qafzeh hominins.

Radiometric dating of hillslope calcrete in the Negev Desert, Israel

2008 ◽  
Vol 104 (11/12) ◽  
Author(s):  
J.C. Vogel ◽  
M.A. Geyh
Keyword(s):  
Open System ◽  
Negev Desert ◽  
Radiometric Dating ◽  
Jordan Valley ◽  
Partial Recrystallization ◽  
Uranium Series ◽  
Uranium Series Dating

The radiometric dating of calcrete is often problematical because impurities and open system conditions affect the apparent ages obtained. By applying both radiocarbon and uranium-series dating to calcrete in colluvium, it is shown that such conditions can be identified. In correlation with the stratigraphy, it is found that partial recrystallization severely decreases the radiocarbon ages of the upslope and shallower samples further down, whereas incorporation of limestone fragments from bedrock significantly increases the apparent ages of some of the uranium-series samples. It is concluded that the hillslope calcrete at the study site near Sede Beker in the Negev Desert, Israel, mainly developed shortly after 40 kyr ago, at a time when the Jordan Valley was being inundated to form the fossil Lake Lisan. Since their formation would have required higher rainfall than today, the results provide further evidence that the whole region was experiencing an increase in precipitation.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

Asian Americans and Pacific Islanders: Employment Issues in the United States

2011 ◽  
Vol 9 (1-2) ◽  
pp. 58-69
Author(s):  
Marlene Kim
Keyword(s):  
United States ◽  
Asian Americans ◽  
The United States ◽  
Current Data ◽  
Pacific Islanders ◽  
Native Hawaiians ◽  
Data Sets ◽  
High Poverty ◽  
Unemployment Rates

Asian Americans and Pacific Islanders (AAPIs) in the United States face problems of discrimination, the glass ceiling, and very high long-term unemployment rates. As a diverse population, although some Asian Americans are more successful than average, others, like those from Southeast Asia and Native Hawaiians and Pacific Islanders (NHPIs), work in low-paying jobs and suffer from high poverty rates, high unemployment rates, and low earnings. Collecting more detailed and additional data from employers, oversampling AAPIs in current data sets, making administrative data available to researchers, providing more resources for research on AAPIs, and enforcing nondiscrimination laws and affirmative action mandates would assist this population.

Past testate amoeba communities in landslide mountain fens (Polish Carpathians): The relationship between shell types and sediment

The Holocene ◽  
2021 ◽  
pp. 095968362199464
Author(s):  
Katarzyna Marcisz ◽  
Krzysztof Buczek ◽  
Mariusz Gałka ◽  
Włodzimierz Margielewski ◽  
Matthieu Mulot ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Testate Amoebae ◽  
Mineral Matter ◽  
Testate Amoeba ◽  
Run Off ◽  
Number Of Factors ◽  
Depth To Water Table ◽  
Polish Carpathians ◽  
The Relationship

Landslide mountain fens formed in landslide depressions are dynamic environments as their development is disturbed by a number of factors, for example, landslides, slopewash, and surface run-off. These processes lead to the accumulation of mineral material and wood in peat. Disturbed peatlands are interesting archives of past environmental changes, but they may be challenging for providing biotic proxy-based quantitative reconstructions. Here we investigate long-term changes in testate amoeba communities from two landslide mountain fens – so far an overlooked habitat for testate amoeba investigations. Our results show that abundances of testate amoebae are extremely low in this type of peatlands, therefore not suitable for providing quantitative depth-to-water table reconstructions. However, frequent shifts of dominant testate amoeba species reflect dynamic lithological situation of the studied fens. We observed that high and stable mineral matter input into the peatlands was associated with high abundances of species producing agglutinated (xenosomic) as well as idiosomic shells which prevailed in the testate amoeba communities in both analyzed profiles. This is the first study that explores testate amoebae of landslide mountain fens in such detail, providing novel information about microbial communities of these ecosystems.

scholarly journals Oldest cave art found in Sulawesi

2021 ◽  
Vol 7 (3) ◽  
pp. eabd4648
Author(s):  
Adam Brumm ◽  
Adhi Agus Oktaviana ◽  
Basran Burhan ◽  
Budianto Hakim ◽  
Rustan Lebe ◽  
...  
Keyword(s):  
Rock Art ◽  
Karst Area ◽  
Uranium Series ◽  
Island Southeast Asia ◽  
South Sulawesi ◽  
Figurative Painting ◽  
Uranium Series Dating ◽  
Cave Paintings ◽  
Minimum Age ◽  
Cave Art

Indonesia harbors some of the oldest known surviving cave art. Previously, the earliest dated rock art from this region was a figurative painting of a Sulawesi warty pig (Sus celebensis). This image from Leang Bulu’ Sipong 4 in the limestone karsts of Maros-Pangkep, South Sulawesi, was created at least 43,900 years ago (43.9 ka) based on Uranium-series dating. Here, we report the Uranium-series dating of two figurative cave paintings of Sulawesi warty pigs recently discovered in the same karst area. The oldest, with a minimum age of 45.5 ka, is from Leang Tedongnge. The second image, from Leang Balangajia 1, dates to at least 32 ka. To our knowledge, the animal painting from Leang Tedongnge is the earliest known representational work of art in the world. There is no reason to suppose, however, that this early rock art is a unique example in Island Southeast Asia or the wider region.

scholarly journals Potential changes in the connectivity of marine protected areas driven by extreme ocean warming

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Luciana Shigihara Lima ◽  
Douglas Francisco Marcolino Gherardi ◽  
Luciano Ponzi Pezzi ◽  
Leilane Gonçalves dos Passos ◽  
Clarissa Akemi Kajiya Endo ◽  
...  
Keyword(s):  
Protected Areas ◽  
Marine Protected Areas ◽  
Oceanic Islands ◽  
Ocean Warming ◽  
Surface Currents ◽  
Southwest Atlantic ◽  
Tropical Ocean ◽  
Regional Effects ◽  
Rcp 8.5

AbstractProjected future climate scenarios anticipate a warmer tropical ocean and changes in surface currents that will likely influence the survival of marine organisms and the connectivity of marine protected areas (MPAs) networks. We simulated the regional effects of climate change on the demographic connectivity of parrotfishes in nine MPAs in the South Atlantic through downscaling of the HadGEM2-ES Earth System Model running the RCP 8.5 greenhouse gas trajectory. Results indicate a tropicalization scenario over the tropical southwest Atlantic following an increase of sea surface temperature (SST) between 1.8 and 4.5 °C and changes in mean surface currents between − 0.6 to 0.5 m s−1 relative to present conditions. High mortality rates will reduce demographic connectivity and increase the isolation of oceanic islands. The simulation of organismal response to ocean warming shows that acclimation can significantly improve (p < 0.001) particle survival, promoting connectivity and tropicalization of MPAs, with potential impacts on their functional integrity and long-term resilience.

scholarly journals Cellular stress signaling activates type-I IFN response through FOXO3-regulated lamin posttranslational modification

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Inah Hwang ◽  
Hiroki Uchida ◽  
Ziwei Dai ◽  
Fei Li ◽  
Teresa Sanchez ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Environmental Changes ◽  
Type I ◽  
Neurogenic Differentiation ◽  
Forkhead Box ◽  
Nuclear Lamin ◽  
Neural Stem Progenitor Cells ◽  
Subsequent Activation ◽  
Methyl Group Transfer

AbstractNeural stem/progenitor cells (NSPCs) persist over the lifespan while encountering constant challenges from age or injury related brain environmental changes like elevated oxidative stress. But how oxidative stress regulates NSPC and its neurogenic differentiation is less clear. Here we report that acutely elevated cellular oxidative stress in NSPCs modulates neurogenic differentiation through induction of Forkhead box protein O3 (FOXO3)-mediated cGAS/STING and type I interferon (IFN-I) responses. We show that oxidative stress activates FOXO3 and its transcriptional target glycine-N-methyltransferase (GNMT) whose upregulation triggers depletion of s-adenosylmethionine (SAM), a key co-substrate involved in methyl group transfer reactions. Mechanistically, we demonstrate that reduced intracellular SAM availability disrupts carboxymethylation and maturation of nuclear lamin, which induce cytosolic release of chromatin fragments and subsequent activation of the cGAS/STING-IFN-I cascade to suppress neurogenic differentiation. Together, our findings suggest the FOXO3-GNMT/SAM-lamin-cGAS/STING-IFN-I signaling cascade as a critical stress response program that regulates long-term regenerative potential.

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