Was Agriculture Impossible during the Pleistocene but Mandatory during the Holocene? A Climate Change Hypothesis

2001 ◽  
Vol 66 (3) ◽  
pp. 387-411 ◽  
Author(s):  
Peter J. Richerson ◽  
Robert Boyd ◽  
Robert L. Bettinger
Keyword(s):  
Dominant Strategy ◽  
Population Pressure ◽  
Human Populations ◽  
The Holocene ◽  
Last Glacial ◽  
Long Run ◽  
High Level ◽  
Almost All ◽  
Short Time ◽  
Climate Proxies

Several independent trajectories of subsistence intensification, often leading to agriculture, began during the Holocene. No plant-rich intensifications are known from the Pleistocene, even from the late Pleistocene when human populations were otherwise quite sophisticated. Recent data from ice and ocean-core climate proxies show that last glacial climates were extremely hostile to agriculture—dry, low in atmospheric CO2, and extremely variable on quite short time scales. We hypothesize that agriculture was impossible under last-glacial conditions. The quite abrupt final amelioration of the climate was followed immediately by the beginnings of plant-intensive resource-use strategies in some areas, although the turn to plants was much later elsewhere. Almost all trajectories of subsistence intensification in the Holocene are progressive, and eventually agriculture became the dominant strategy in all but marginal environments. We hypothesize that, in the Holocene, agriculture was, in the long run, compulsory. We use a mathematical analysis to argue that the rate-limiting process for intensification trajectories must generally be the rate of innovation of subsistence technology or subsistence-related social organization. At the observed rates of innovation, population growth will always be rapid enough to sustain a high level of population pressure. Several processes appear to retard rates of cultural evolution below the maxima we observe in the most favorable cases.

scholarly journals The Eurasian lynx (Lynx lynx) in the Ukrainian Polissia: state of population and conservation issues

2021 ◽  
Vol 2021 (21) ◽  
pp. 91-108
Author(s):  
Sergiy Zhyla ◽  
Keyword(s):  
Dynamic Equilibrium ◽  
Action Plan ◽  
Well Being ◽  
Lynx Lynx ◽  
Eurasian Lynx ◽  
Census Methods ◽  
In The Wild ◽  
High Level ◽  
Almost All ◽  
Short Time

The issue of survey, monitoring, and protection of the lynx in the Ukrainian Polissia based on the results of research carried out in 2013–2021 is considered. European census methods do not include the identification of traces of territorial individuals and of those that disperse. Lynx family groups living along the border or at the border of land users should be accounted for 50 % of the established number, so that there is no double counting. The use of photo traps to identify lynx individuals in the wild and then to establish the total lynx population is less effective and more costly than traditional trace-based techniques. Even in the absence of snow, repeated surveys on trails (five visits to the territory with intervals of at least a week), it is possible to establish the presence of almost all individuals of the lynx in the selected area. The reasons for the decline in the number of species in 2015–2017 from 80–100 to 40 individuals and the prospects for effective management of the Polissia population in the future are considered. The number of lynx in 2015–2017 in the Ukrainian Polissia decreased significantly and was at a minimum level for a short time. Since 2018, there has been a gradual increase in the number, especially rapid in the period 2019–2021. The decline in the number of the species in 2015–2017 indicates the need to create a national lynx action plan in Ukraine. The presence of a strong Baltic lynx population north of the Ukrainian Polissia, specifics of territorial distribution of forests, river network, forestless territories, including the Ovruch-Slovenian ridge, create clear eco-corridors in the Ukrainian Polissia for such forest-dwelling species as the lynx. As of 2021, fluctuations in predator-prey systems (wolf, lynx vs deer, wild boar, beaver) have apparently stopped and a new dynamic equilibrium has been established between these species. The lynx has recently proved that it is able to survive even in an anthropogenically altered landscape with a relatively high level of economic activity, which allows the well-being of the population of this species to be predicted in Ukraine.

DFT Benchmark Study of the O--O Bond Dissociation Energy in Peroxides Validated with High-Level Ab-Initio Calculations

2019 ◽  
Author(s):  
Danilo Carmona ◽  
Pablo Jaque ◽  
Esteban Vöhringer-Martinez
Keyword(s):  
Reference Value ◽  
Basis Set ◽  
Basis Sets ◽  
Mean Deviation ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
The Mean ◽  
Experimental Values ◽  
High Level ◽  
Almost All

<div><div><div><p>Peroxides play a central role in many chemical and biological pro- cesses such as the Fenton reaction. The relevance of these compounds lies in the low stability of the O–O bond which upon dissociation results in radical species able to initiate various chemical or biological processes. In this work, a set of 64 DFT functional-basis set combinations has been validated in terms of their capability to describe bond dissociation energies (BDE) for the O–O bond in a database of 14 ROOH peroxides for which experimental values ofBDE are available. Moreover, the electronic contributions to the BDE were obtained for four of the peroxides and the anion H2O2− at the CBS limit at CCSD(T) level with Dunning’s basis sets up to triple–ζ quality provid- ing a reference value for the hydrogen peroxide anion as a model. Almost all the functionals considered here yielded mean absolute deviations around 5.0 kcal mol−1. The smallest values were observed for the ωB97 family and the Minnesota M11 functional with a marked basis set dependence. Despite the mean deviation, order relations among BDE experimental values of peroxides were also considered. The ωB97 family was able to reproduce the relations correctly whereas other functionals presented a marked dependence on the chemical nature of the R group. Interestingly, M11 functional did not show a very good agreement with the established order despite its good performance in the mean error. The obtained results support the use of similar validation strategies for proper prediction of BDE or other molecular properties by DF Tmethods in subsequent related studies.</p></div></div></div>

Methyl mercury in the dutch rhine delta

1994 ◽  
Vol 30 (10) ◽  
pp. 213-219 ◽  
Author(s):  
Hendrik Pieters ◽  
Victor Geuke
Keyword(s):  
Suspended Matter ◽  
Methyl Mercury ◽  
Mercury Contamination ◽  
Benthic Organisms ◽  
Considerable Decrease ◽  
Continuous Sedimentation ◽  
Highly Correlated ◽  
High Level ◽  
Almost All

Samples of yellow eel from various locations in the Dutch Rhine area have been analyzed for trend monitoring of mercury since 1977. In the western Rhine delta mercury levels in eels have hardly changed since the seventies, whereas in the eastern part of the Dutch Rhine area a considerable decrease of mercury concentrations in eel has occurred. Because of continuous sedimentation of contaminated suspended matter transported from upstream regions, accumulation rates and concentrations of mercury in eel in the western Rhine delta remained at a relatively high level. Analyses of methyl mercury in biota have been performed to elucidate the role of methyl mercury in the mercury contamination of the Dutch Rhine ecosystem. Low percentages of methyl mercury were observed in zooplankton (3 to 35%). In benthic organisms (mussels) percentages of methyl mercury ranged from 30 to 57%, while in fish species and liver of aquatic top predator birds almost all the mercury was present in the form of methyl mercury (&gt; 80%). During the period 1970-1990 mercury concentrations of suspended matter in the eastern Rhine delta have drastically decreased. These concentrations seemed to be highly correlated with mercury concentrations of eel (R = 0.84). The consequences of this relation are discussed.

Application of Natural Dye Obtained from Sweet Indrajao on Fabrics

2020 ◽  
Vol 6 (3) ◽  
pp. 180-191
Author(s):  
Kavitha Chandrasekaran
Keyword(s):  
Potassium Dichromate ◽  
Bacterial Pathogens ◽  
Ultrasonic Method ◽  
Ferrous Sulphate ◽  
Fine Powder ◽  
Cost Effective ◽  
Metal Salts ◽  
Cow Dung ◽  
Long Run ◽  
Almost All

Background:: In the long run, synthetic tints were found to be harmful to the chemicals. As a result natural tints have come to be used for their many intrinsic values. The main reason being, then availability of local plants as the main source of natural colorants. Their easy availability in the country being zero cost – effective and planted for other purposes are the main reasons for utilizing them as natural tints. Almost all the parts of the plants, namely stem, leaves, fruits, seeds, barks etc. are used for extracting natural colour. In addition, they are antimicrobial antifungal, insect – repellant deodorant, disinfectant having medicinal values. Methods:: Sweet Indrajao leaves were cleaned by washing with water and dried under direct sunlight and ground as fine powder. A fine strainer was used to remove the wastages. After all these processes, 1-kilogram leaves weighed 318 grams. Then, it is put in 75% ethanol 25% water and heated in a breaker which in kept over a water bath for 2 hours. After this, the contents were filtered and kept in a separate beaker. Bleached fleece draperies stained with stain extract were made to become wet and put into different stain baths which contain the required amount of stain extract and water. Acetic acid was added to it after 20 minutes. The fleece drapery was stained for about one hour at 60oC. The draperies thus stained were removed, squeezed, and put to treatment with metal salts without washing. Different metal salts were used for the treatment using 3% of any one of the chemical mordants like alum, stannous chloride, potassium dichromate, ferrous sulphate, nickel sulphate, copper sulphate and natural mordants such as myrobolan, turmeric, cow dung, Banana sap juice at 60oC for 30 minutes with MLR of 1:30. The stained draperies were washed repeatedly in all the three methods in water and dried in air. At last, the stained draperies were put to soap with soap solution at 60oC for 10 minutes. The draperies were repeatedly washed in water and dried under the sun. Results:: Sweet Indrajao leaves discharged colour easily in alcoholic water. The fleece draperies were stained with chemical and natural mordants. It was observed that the stain uptake was found to be good in post-mordanting method. Ultrasonication has clearly improved the stainability of the draperies at pH 3 and 3.5 values. The pH decreases the stain ability under both Conventional and Ultrasonic conditions. The colour strength increases with an increase in staining temperature in both cases of US and CH methods. Conclusion:: Sweet Indrajao.L has been found to have good ultrasonic potential as a stain plant. The stain uptake as well as the fastness properties of the fleece drapery were found to enhance when metal mordant was used in conjugation with ultra-sonication for the extract of Sweet Indrajao. It was also found that the enhancement of staining ability was better without mordant draperies. The dye extract showed good antibacterial activity against the three bacterial pathogens. Among the three bacterial pathogens, dye extract showed more effective against Escherichia coli pathogens and dye extract showed more effective against Aspergillus pathogens. Hence, the ultrasonic method of drapery staining may be appropriate and beneficial for society at large in future.

scholarly journals Liquid Biopsy and Other Non-Invasive Diagnostic Measures in PCNSL

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2665
Author(s):  
Alexander Baraniskin ◽  
Roland Schroers
Keyword(s):  
Central Nervous System Lymphoma ◽  
Circulating Tumor Dna ◽  
Mri Findings ◽  
Diagnostic Measures ◽  
Non Hodgkin Lymphoma ◽  
Specificity And Sensitivity ◽  
Demyelinating Lesions ◽  
Granulomatous Diseases ◽  
High Level ◽  
Almost All

Primary central nervous system lymphoma is a rare but highly aggressive form of non-Hodgkin lymphoma that remains confined to the CNS neuroaxis. The diagnosis of PCNSL requires a high level of suspicion as clinical presentation varies depending on the involved CNS areas. Neurological symptoms and MRI findings may mimic gliomas, demyelinating lesions, or infectious and granulomatous diseases. Almost all PCNSL patients undergo invasive surgical procedures for definite diagnosis. Stereotactic biopsy is still the gold standard in achieving a diagnostic accuracy of 73–97%. Both the potential procedural morbidity and mortality, as well as the time to definite histopathologic diagnosis resulting in delays of treatment initiation, have to be considered. On the contrary, minimally invasive procedures, such as MRI, CSF cytology, and flow cytometry, still have limited value due to inferior specificity and sensitivity. Hence, novel diagnostic approaches, including mutation analyses (MYD88) in circulating tumor DNA (ctDNA) and the determination of microRNAs (miR-21, miR-19b, and miR-92) as well as cytokine levels (IL10 and IL6) in blood, cerebrospinal fluid (CSF), and vitreous fluid (VRF), move into the focus of investigation to facilitate the diagnosis of PCNSL. In this review, we outline the most promising approaches that are currently under clinical consideration.

scholarly journals Constituent elements of insoluble and non-volatile particles during the Last Glacial Maximum exhibited in the Dome Fuji (Antarctica) ice core

2009 ◽  
Vol 55 (191) ◽  
pp. 552-562 ◽  
Author(s):  
Yoshinori Iizuka ◽  
Takayuki Miyake ◽  
Motohiro Hirabayashi ◽  
Toshitaka Suzuki ◽  
Sumito Matoba ◽  
...  
Keyword(s):  
Last Glacial Maximum ◽  
Calcium Ion ◽  
Ice Core ◽  
Ice Cores ◽  
Glacial Maximum ◽  
Ion Concentrations ◽  
Last Glacial ◽  
Insoluble Particles ◽  
Almost All ◽  
Constituent Elements

AbstractIn order to find environmental signals based on the dust and calcium-ion concentrations in ice cores, we determine the constituent elements of residue particles obtained after melting ice samples. We have designed a sublimating system that operates at −45°C, below the eutectic temperatures of major salts. This system permits us to obtain a great many non-volatile particles. After studying the non-volatile particles, we immersed them in water to remove soluble particles and compounds. We thereby analyzed a total of 1272 residue particles (from the melted sample), 2418 non-volatile particles (after sublimation) and 1463 insoluble particles taken from five sections of Last Glacial Maximum ice from the Dome Fuji (Antarctica) ice core. Their constituent elements were determined by scanning electron microscopy/energy-dispersive X-ray spectrometry (SEM-EDS) and compared to the dust, calcium-ion and sodium-ion concentrations measured by ion chromatography. Our results indicate that >99.9% of the insoluble particles contain silicon but no sulfur, nitrogen or chlorine. A significant number of the non-volatile particles, however, contain sulfur and chlorine. We conclude that insoluble dust consists mostly of silicate, that almost all calcium ions originate from calcium sulfate and that almost all sodium ions originate from sodium sulfate and sodium chloride.

POVERTY REDUCTION, UNEMPLOYMENT AND RURAL DEVELOPMENT; AFTERMATH OF COVID-19 PANDEMIC IN NIGERIA

2021 ◽  
Vol 9 (1) ◽  
pp. 36-49
Author(s):  
Oderinu Hassana ◽  
◽  
Kadir Mumini ◽  
Tijani Adebayo ◽  
Keyword(s):  
Economic Development ◽  
Rural Development ◽  
Rural Areas ◽  
Poverty Reduction ◽  
Design Method ◽  
Gear Up ◽  
Global Pandemic ◽  
High Level ◽  
Almost All ◽  
Self Administered Questionnaire

Nigeria has one of the countries whose experience of poverty and unemployment is on the high side makes this study to look into the effect of the economic lockdown during the global pandemic in the country, with the aim of making effort on how this effect can be translated into economic development. Survey research design method was adopted with self-administered questionnaire used to collect data. Findings revealed that in Nigeria COVID -19 outbreak effects was felt in almost all sectors and the aftermath greatly affected the country’s GDP and this adversely affect rural development in the country, which translated to a worrisome rate of poverty and unemployment. Hence, both individual and government have now seen that campaigning for economic diversification is not sufficient for economic development but rather a prompt swing into action by all is needed for sustainable development of rural areas to respond to the worrisome rate of unemployment and in turn high level of poverty caused by the COVID-19 lockdown in the country. It was recommended that government at all level as well as individuals and stakeholders should put in place actions that would gear up rural development and set policies at their various helms of affairs that would encourage economic participation of all citizens in all sector of the economy.

FOOD SAFETY KNOWLEDGE, ATTITUDES AND PRACTICES AMONG FEDERAL UNIVERSITY OF AGRICULTURE STUDENTS IN ABEOKUTA

2017 ◽  
Vol 15 (1) ◽  
pp. 94-107
Author(s):  
M O ADEGUNWA ◽  
M I SANUSI ◽  
H A BAKARE ◽  
A M OMEMU
Keyword(s):  
Food Safety ◽  
Contributing Factors ◽  
Safety Attitudes ◽  
Attitudes And Practices ◽  
Handling Practices ◽  
High Level ◽  
Almost All ◽  
The University ◽  
Safety Knowledge ◽  
Safety Attitude

Improper practices, poor attitudes and lack of knowledge by food handlers are contributing factors for the spread of foodborne diseases. Food safety knowledge is an important factor in improving food safety practices and subsequently food safety attitude. This study is aimed at exploring the food safety knowledge, practice and attitude of FUNAAB students. A self completed questionnaire was answered by randomly selected 270 students from each of the nine (9) colleges in the university and analyzed using SPSS software. The study revealed that almost all of the students had a high level of food safety awareness but the knowledge was not to large extent translated into practice. Majority of the students also had good food safety attitudes as many of them are willing to change their food handling behav-iour when they know they are incorrect (94.8%). The study further revealed similar level of food safety knowledge between the male and female. Despite the level of students’ knowledge, their choice of eating place on campus was determined by the price of the food. This study therefore concluded that good knowledge of food safety does not determine students’ safe handling practices and choice of eating place.Keywords: Food safety

The dynamics of Holocene monsoon based on meteoric 10Be at Kunlun Pass on the northeastern Qinghai-Tibet Plateau

2021 ◽  
Author(s):  
Peng Chen ◽  
Zhongbo Yu ◽  
Markus Czymzik ◽  
Ala Aldahan ◽  
Jinguo Wang ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Summer Monsoon ◽  
Asian Summer Monsoon ◽  
Early Holocene ◽  
Tibet Plateau ◽  
The Holocene ◽  
Proxy Records ◽  
Low Levels ◽  
High Level ◽  
Qinghai Tibet Plateau

&lt;p&gt;Multiple proxy records have been used for the understanding of environmental and climate changes during the Holocene. For the first time, we here measure meteoric &lt;sup&gt;10&lt;/sup&gt;Be isotope of sediments from a drill core collected at the Kunlun Pass (KP) on the northeastern Qinghai-Tibet Plateau (NETP) to investigate mositure and atmospheric circulation changes during the Holocene. The &lt;sup&gt;10&lt;/sup&gt;Be flux suggests relative low levels in the Early Holocene, followed by a sharp increase to high values at around 4 ka BP (4 ka BP = 4000 years before present). Afterwards, the &lt;sup&gt;10&lt;/sup&gt;Be flux remains on a high level during the Late Holocene, but decreases slightly towards today. These &lt;sup&gt;10&lt;/sup&gt;Be deposition patterns are compared to moisture changes in regions dominated by the Indian Summer Monsoon (ISM), East Asian Summer Monsoon (EASM), and the Westerlies. Different from the gradual changes in monsoon patterns, the &lt;sup&gt;10&lt;/sup&gt;Be data reveal low levels during the Early Holocene until ~4 ka BP when an obvious increase was indicated and a relative high level continues to this day, which is relatively more in agreement with patterns of the Westerlies. This finding provides a new evidence for a shift in the dominant pattern of atmospheric circulation at the KP region from a more monsoonal one to one dominated by the Westerlies. Our results improve the understanding of non-stationary interactions and spatial relevance of the EASM, the ISM and the Westerlies on the Qinghai-Tibet Plateau.&lt;/p&gt;

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