On Auxiliary Fields in BF Theories

We discuss the structure of auxiliary fields for non-Abelian BF theories in arbitrary dimensions. By modifying the classical BRST operator, we build the on-shell invariant complete quantum action. Therefore, we introduce the auxiliary fields which close the BRST algebra and lead to the invariant extension of the classical action.Comment: 7 pages, minor changes, typos in equations corrected and acknowledgements adde

The influence of citrate anion on Ni(II) removal by raw red mud from aluminum industry

The removal of Ni(II) from aqueous solutions by raw red mud powder was studied in the absence and in the presence of citrate ligand, as a function of process parameters. Using lower initial Ni(II) concentration (10(-3) mol/L) detectable amounts were found only at initial pH 3, whereas for higher concentration (2 x 10(-3) mol/L) removal increased simultaneously with pH in the range 3-4 and at pH gt 8. Process efficiency was suppressed in the presence of citrate. However, at Ni/Citrate molar ratios 1:0.25 and 1:0.5, 10-20% decrease was noticed in acidic media, while the negative influence diminished with the rise of pH. At higher ligand rates, formation of stable aqueous complex between Ni(II) and citrate significantly reduced metal removal in the whole tested initial pH range (3-10). Due to instantaneous pH rise above 8, removal of Ni(II) from 10(-3) mol/L solution was completed in 5 min. Kinetic data demonstrated slower Ni(II) uptake using both solutions of higher initial Ni(II) concentrations and Ni/Citrate solutions. At initial pH 5, estimated capacity towards Ni(II) was found to be 27.4 mg/g, without citrate. For Ni/Citrate molar ratios 1:0.25 and 1:0.5, capacities decreased slightly to 25 mg/g and 21 mg/g, whereas at equimolar and higher concentrations, citrate significantly inhibited Ni(II) immobilization (7.6 mg/g and 2.5 mg/g, respectively for Ni/Citrate ratios 1:1 and 1:2). The results demonstrated beneficial effect of red mud high alkalinity on Ni(II) removal. The sorbent satisfactorily immobilize nickel from solutions having initial Ni/Citrate molar ratios lower than 1:1, and neutral to alkaline initial pH. FUR analysis confirmed that red mud can act as a removal agent for Ni(II), Ni/Citrate complex and free citrate ligand

Effect of acid treatment on red mud properties with implications on Ni(II) sorption and stability

Red mud, a heterogeneous mineral waste from aluminum industry, can be beneficially utilized as a sorbent. High alkalinity and the amount of water soluble ions can limit some of its applications. This study's aim was to explore and correlate physicochemical properties and sorption efficiencies of acid treated red mud. Sorbents (BRM0.05-BRM1), obtained by varying HCl concentration (0.05-1 mol/L), were characterized in terms of mineralogical composition, surface functional groups, electrical conductivity (EC) and the point of zero charge (pH(PZC)). Removal of Ni(II) ions was tested in batch conditions. Sorbents EC and pH(PZC) values decreased with the increase of acid concentration. Structural analysis revealed that sodalite and calcite phases were completely lost starting from the samples BRM0.25 and BRM0.5, respectively. Along with the sodalite dissolution, gibbsite precipitation was observed. Ni(II) sorption increased with the increase of initial pH from 2 to 4, while at pH gt 4 it depended only on sorbent material. A radical drop of maximum sorption capacities was associated with the increase of acid concentration to 0.25 mol/L, whereas additional rise to 1 mol/L caused minor fluctuations. Fully loaded sorbents BRM0.25-BRM0.1 also exhibited considerable lower stability over a range of investigated pH conditions. Dissolution of sodalite and calcite, and the consequent reduction of buffering capacities can be identified as the main reasons for decreasing sorption efficiency. Sample BRM0.05 was efficient in terms of both sorption and stability, yet environmentally more benign than the original red mud due to the lower alkalinity and content of water soluble ions

Unsupervised classification and multi-criteria decision analysis as chemometric tools for the assessment of sediment quality: A case study of the Danube and Sava River

The aim of this study was to evaluate the quality of freshwater sediments by means of three chemometric techniques for multi-criteria analysis and decision: self-organizing network (SON), self-organizing map (SOM) and PROMETHEE&GAIA (Preference Ranking Organization Method for Enrichment Evaluation with Geometrical Analysis for Interactive Aid). Selected chemometric techniques were applied to the results of Pb, Cd, Zn, Cu, Ni, Cr, Hg and As content in thirty Danube and fourteen Sava river sediment samples from Serbia. The potential toxicity of sediments was estimated using Probable Effect Concentrations quotients (mean PEC-Q). According to the SON analysis the Danube sediment samples were divided into three classes, Class I (mean PEC-Q range 0.27-0.51), Class II (mean PEC-Qrange 0:50-0.70), and Class III (mean PEC-Qrange 0.77-0.97), while the Sava samples were divided into two classes, Class II (two samples, mean PEC-Qvalues 0.65 and 0.69) and Class III (mean PEC-Q range 0.69-1.00). Using the SOM cluster analysis, both Danube and Sava sediment samples were classified into five subclusters, on the basis of the metal concentration level and further ranked into three levels (for remediation, moderately polluted and not polluted) by the use of multi-criteria ranking PROMETHEE method. Graphical presentation of the results obtained by PROMETHEE method using GAIA descriptive tool has provided an insight into the distribution of examined elements in sediments and has shown a significant correlation between some elements. On the basis of the results obtained, it has been concluded that the proposed chemometric approach could provide useful information in the sediment quality assessment

The genetic history of the Southern Arc: a bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra?West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe. Stories about the peopling?and people?of Southern Europe and West Asia have been passed down for thousands of years, and these stories have contributed to our historical understanding of populations. Genomic data provide the opportunity to truly understand these patterns independently from written history. In a trio of papers, Lazaridis et al. examined more than 700 ancient genomes from across this region, the Southern Arc, spanning 11,000 years, from the earliest farming cultures to post-Medieval times (see the Perspective by Arbuckle and Schwandt). On the basis of these results, the authors suggest that earlier reliance on modern phenotypes and ancient writings and artistic depictions provided an inaccurate picture of early Indo-Europeans, and they provide a revised history of the complex migrations and population integrations that shaped these cultures. ?SNV A web of migrations between Anatolia, its neighbors, and the Steppe suggests a West Asian origin of Indo-Anatolian languages

A genetic probe into the ancient and medieval history of Southern Europe and West Asia

Literary and archaeological sources have preserved a rich history of Southern Europe and West Asia since the Bronze Age that can be complemented by genetics. Mycenaean period elites in Greece did not differ from the general population and included both people with some steppe ancestry and others, like the Griffin Warrior, without it. Similarly, people in the central area of the Urartian Kingdom around Lake Van lacked the steppe ancestry characteristic of the kingdom’s northern provinces. Anatolia exhibited extraordinary continuity down to the Roman and Byzantine periods, with its people serving as the demographic core of much of the Roman Empire, including the city of Rome itself. During medieval times, migrations associated with Slavic and Turkic speakers profoundly affected the region

Ancient DNA from Mesopotamia suggests distinct Pre-Pottery and Pottery Neolithic migrations into Anatolia

We present the first ancient DNA data from the Pre-Pottery Neolithic of Mesopotamia (Southeastern Turkey and Northern Iraq), Cyprus, and the Northwestern Zagros, along with the first data from Neolithic Armenia. We show that these and neighboring populations were formed through admixture of pre-Neolithic sources related to Anatolian, Caucasus, and Levantine hunter-gatherers, forming a Neolithic continuum of ancestry mirroring the geography of West Asia. By analyzing Pre-Pottery and Pottery Neolithic populations of Anatolia, we show that the former were derived from admixture between Mesopotamian-related and local Epipaleolithic-related sources, but the latter experienced additional Levantine-related gene flow, thus documenting at least two pulses of migration from the Fertile Crescent heartland to the early farmers of Anatolia

The genomic history of southeastern Europe

Farming was first introduced to Europe in the mid-seventh millennium bc, and was associated with migrants from Anatolia who settled in the southeast before spreading throughout Europe. Here, to understand the dynamics of this process, we analysed genome-wide ancient DNA data from 225 individuals who lived in southeastern Europe and surrounding regions between 12000 and 500 bc. We document a west-east cline of ancestry in indigenous hunter-gatherers and, in eastern Europe, the early stages in the formation of Bronze Age steppe ancestry. We show that the first farmers of northern and western Europe dispersed through southeastern Europe with limited hunter-gatherer admixture, but that some early groups in the southeast mixed extensively with hunter-gatherers without the sex-biased admixture that prevailed later in the north and west. We also show that southeastern Europe continued to be a nexus between east and west after the arrival of farmers, with intermittent genetic contact with steppe populations occurring up to 2,000 years earlier than the migrations from the steppe that ultimately replaced much of the population of northern Europe.Iain Mathieson … Wolfgang Haak … David Reic