105 research outputs found
Vinča-Belo Brdo, a late neolithic site in Serbia consideration of the macro-botanical remains as indicators of dietary habits
The analysis of macro-botanical remains from the late Neolithic site of Vinča-Belo Brdo has provided first information on the range of crops and wild plants present at the site, and revealed their potential role as foodstuffs. The abundance and distribution of certain plant taxa across different archaeological deposits suggests to what extent they were used within the settlement. The analyzed plant remains also offer insight into the types of food consumed by Vinča residents and serve as a basis for inferring the seasonality and method of food provision/production and activities related to plant use. [Projekat Ministarstva nauke Republike Srbije, br. 177012: Society, spiritual and material culture and communications in prehistory and early history of the Balkans
Research correlation vegetation index of corn with speed of movement sensor and elevation of field
This paper presents field scouting of corn in order to determine the content of nitrogen in the green parts of the plants. The aim was to measure the vegetative index using two optical sensors by OptRx AGL Technology. The sensors are positioned at a distance of 3.5 m, individually observing five rows of corn. The speed of movement of the tractor and also elevation of field are varied. The measured vegetative index of the plants is correlated, in first, with the speed of the sensor on the platform. The measured vegetative index of the plants is correlated after that with elevation also. Both of that case are shown that the Normalised Difference Red Edge (NDRE) as represent of vegetative index is not correlated with speed and elevation. This Results represented with Pearson Correlation Coefficient and Spearman's Correlation Coefficient are statistical signatifical. This conclusions are valid only for short rang of speed and elevation research. Average speed was 6,39 km/hr and rang of elevation was 1.6 m (106.8-108.4 m)
The effects of mineral adsorbents added to broilers diet on breast meat quality
The aim of these investigations was to determine the influence of mineral adsorbents Minazel and Minazel Plus added into broiler diet, on the carcass quality and nutritional, technological and sensory properties of breast meat. The examination was done on Cobb 500 provenience divided into 4 groups: control group C (fed without addition of mineral adsorbent), experimental group E I (0.5% of Minazel), experimental group E II (0.2% of Minazel Plus), experimental group E III (0.3% of Minazel Plus). The results showed that the broilers fed with the addition of mineral adsorbents, had a higher (P < 0.01) mass of chilled carcass ready to grill and breast mass, than the broilers of the control group. Based on the parameters and criteria for defining the quality of chicken breast meat (pHu and L*) it can be concluded that meat of all groups had in average normal quality. According to the results of sensory analyzed roasted breast meat, meat of experimental groups had preferable smell and tenderness
Stereoselektivne sinteze α-hidroksi-β-aminokiselina iz prirodnih hiralnih prekursora
A method for the stereoselective homologation of -amino acids into syn-α-hydroxy-β-amino acids is described, based on the conversion of stereoisomeric cyanohydrins into trans-oxazolines. The synthetic potential of the method is illustrated in the enantioselective formal synthesis of Bestatin.Opisana je metoda za stereoselektivnu sintezu α-hidroksi-β-aminokiselina syn-konfiguracije, polazeći od α-aminokiselina, kao prirodnih hiralnih prekursora. Enantioselektivnost procesa zavisi od strukture polazne aminokiseline, kao i reakcionih uslova. Primena ove metode ilustrovana je u sintezi (2S,3R)-3-amino-2-hidroksi-4-fenilbutanske kiseline, konstituenta nekoliko važnih biološki aktivnih jedinjenja
A Vinča potscape: formal chronological models for the use and development of Vinča ceramics in south-east Europe.
Recent work at Vinča-Belo Brdo has combined a total of more than 200 radiocarbon dates with an array of other information to construct much more precise narratives for the structural history of the site and the cultural materials recovered from it. In this paper, we present the results of a recent attempt to construct formal models for the chronology of the wider Vinča potscape, so that we can place our now detailed understanding of changes at Belo Brdo within their contemporary contexts. We present our methodology for assessing the potential of the existing corpus of more than 600 radiocarbon dates for refining the chronology of the five phases of Vinča ceramics proposed by Milojčić across their spatial ranges, including a total of 490 of them in a series of Bayesian chronological models. Then we outline our main results for the development of Vinča pottery. Finally, we discuss some of the major implications for our understanding of the source, character and tempo of material change
On the azo dyes derived from benzoic and cinnamic acids used as photosensitizersin dye-sensitized solar cells
In order to get a better insight into the relationship between molecular structure and photovoltaic performance, six monoazo dye molecules containing benzoic and cinnamic acid moieties were synthesized and their photovoltaic properties were studied. Three of them have not been previously used in solar cells. Spectroscopic measurements of the investigated compounds coupled with theoretical calculations were performed. Short-circuit current density, open-circuit voltage, and fill-factor were determined. It was found that a larger amount of short-circuit current density will be generated if the HOMO-LUMO energy gap is lower, determined by the stability of the molecule and the electronic effect of the donor moiety. Among both series of synthesized dye molecules, the highest obtained values of short-circuit current density were achieved with (2-hydroxynaphthalene-1-ylazo)benzoic acid and (2-hydroxynaphthalene-1-ylazo)cinnamic acid, and thus they were regarded as promising candidates for application in dye-sensitized solar cells
Widespread exploitation of the honeybee by early Neolithic farmers.
This is the author's version of an article subsequently published in Nature. The definitive version is available from the publisher via: doi: 10.1038/nature15757.Copyright © 2015, Rights Managed by Nature Publishing GroupThe pressures on honeybee (Apis mellifera) populations, resulting from threats by modern pesticides, parasites, predators and diseases, have raised awareness of the economic importance and critical role this insect plays in agricultural societies across the globe. However, the association of humans with A. mellifera predates post-industrial-revolution agriculture, as evidenced by the widespread presence of ancient Egyptian bee iconography dating to the Old Kingdom (approximately 2400 BC). There are also indications of Stone Age people harvesting bee products; for example, honey hunting is interpreted from rock art in a prehistoric Holocene context and a beeswax find in a pre-agriculturalist site. However, when and where the regular association of A. mellifera with agriculturalists emerged is unknown. One of the major products of A. mellifera is beeswax, which is composed of a complex suite of lipids including n-alkanes, n-alkanoic acids and fatty acyl wax esters. The composition is highly constant as it is determined genetically through the insect's biochemistry. Thus, the chemical 'fingerprint' of beeswax provides a reliable basis for detecting this commodity in organic residues preserved at archaeological sites, which we now use to trace the exploitation by humans of A. mellifera temporally and spatially. Here we present secure identifications of beeswax in lipid residues preserved in pottery vessels of Neolithic Old World farmers. The geographical range of bee product exploitation is traced in Neolithic Europe, the Near East and North Africa, providing the palaeoecological range of honeybees during prehistory. Temporally, we demonstrate that bee products were exploited continuously, and probably extensively in some regions, at least from the seventh millennium cal BC, likely fulfilling a variety of technological and cultural functions. The close association of A. mellifera with Neolithic farming communities dates to the early onset of agriculture and may provide evidence for the beginnings of a domestication process.Natural Environment Research Council (NERC)English HeritageEuropean Research Council (ERC)Leverhulme TrustMinistère de la Culture et de la CommunicationMinistère de l’Enseignement Supérieur et de la RechercheRoyal SocietyWellcome Trus
Ancient pigs reveal a near-complete genomic turnover following their introduction to Europe
Archaeological evidence indicates that pig domestication had begun by ∼10,500 y before the present (BP) in the Near East, and mitochondrial DNA (mtDNA) suggests that pigs arrived in Europe alongside farmers ∼8,500 y BP. A few thousand years after the introduction of Near Eastern pigs into Europe, however, their characteristic mtDNA signature disappeared and was replaced by haplotypes associated with European wild boars. This turnover could be accounted for by substantial gene flow from local European wild boars, although it is also possible that European wild boars were domesticated independently without any genetic contribution from the Near East. To test these hypotheses, we obtained mtDNA sequences from 2,099 modern and ancient pig samples and 63 nuclear ancient genomes from Near Eastern and European pigs. Our analyses revealed that European domestic pigs dating from 7,100 to 6,000 y BP possessed both Near Eastern and European nuclear ancestry, while later pigs possessed no more than 4% Near Eastern ancestry, indicating that gene flow from European wild boars resulted in a near-complete disappearance of Near East ancestry. In addition, we demonstrate that a variant at a locus encoding black coat color likely originated in the Near East and persisted in European pigs. Altogether, our results indicate that while pigs were not independently domesticated in Europe, the vast majority of human-mediated selection over the past 5,000 y focused on the genomic fraction derived from the European wild boars, and not on the fraction that was selected by early Neolithic farmers over the first 2,500 y of the domestication process
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