Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show ...that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo‐ fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from analyses of the interannual variability in biomass burning shown by remote‐sensing observations of month‐by‐month burnt area between 1996 and 2008, our results signal a serious cause for concern in the face of continuing global warming.
Key Points
Sedimentary charcoal records were analyzed over the past 21 kyr
Changes in fire regime are predictable from changes in regional climates
Temperature is the most important driver of fire over the last 21 kyr
Records of past climate variability and associated vegetation response exist in various regions throughout Central and Eastern Europe (CEE). To date, there has been no coherent synthesis of the ...existing palaeo-records. During an INTIMATE meeting (Cluj Napoca, Romania) focused on identifying CEE paleo-records, it was decided to address this gap by presenting the palaeo-community with a compilation of high-quality climatic and vegetation records for the past 60–8 ka. The compilation should also serve as a reference point for the use in the modelling community working towards the INTIMATE project goals, and in data-model inter-comparison studies. This paper is therefore a compilation of up to date, best available quantitative and semi-quantitative records of past climate and biotic response from CEE covering this period. It first presents the proxy and archive used. Speleothems and loess mainly provide the evidences available for the 60–20 ka interval, whereas pollen records provide the main source of information for the Lateglacial and Holocene. It then examines the temporal and spatial patterns of climate variability inferred from different proxies, the temporal and spatial magnitude of the vegetation responses inferred from pollen records and highlights differences and similarities between proxies and sub-regions and the possible mechanisms behind this variability. Finally, it identifies weakness in the proxies and archives and their geographical distribution. This exercise also provides an opportunity to reflect on the status of research in the area and to identify future critical areas and subjects of research.
•A comprehensive review of climate change and impacts on vegetation in Central and Eastern Europe.•Synchronous climate shifts in CEE and the wider North Atlantic region between 14.7 and 8 ka.•Reduced magnitude of these climatic shifts in the continental part of Europe.•Cooling intervals between 14.7 and 11.7 ka cal BP strongly expressed during winters.•Vegetation in CEE responded less drastically to the climate shifts compared to Western Europe.
The usefulness of sedimentary charcoal records to document centennial to millennial scale trends in aspects of fire regimes (frequency, severity) is widely acknowledged, yet the long-term variability ...in these regimes is poorly understood. Here, we use a high-resolution, multi-proxy analysis of a lacustrine sequence located in the lowlands of Transylvania (NW Romania), alongside global climate simulations in order to disentangle the drivers of fire regimes in this dry climatic region of Central-Eastern Europe. Periods of greater fire activity and frequency occurred between 10,700 and 7100 cal yr BP (mean Fire Interval = mFI 112 yr), and between 3300 and 700 cal yr BP (mFI 150 yr), whereas intervals of lower fire activity were recorded between 12,000 and 10,700 cal yr BP (mFI 217 yr), 7100 and 3300 cal yr BP (mFI 317 yr), and over last 700 years (no fire events detected). We found good correlations between simulated early summer (June, July) soil moisture content and near-surface air temperature with fire activity, particularly for the early to mid Holocene. A climate–fire relationship is further supported by local hydrological changes, i.e., lake level and runoff fluctuations. Fuel limitation, as a result of arid and strongly seasonal climatic conditions, led to low fire activity before 10,700 cal yr BP. However, fires were most frequent during climatically drier phases for the remaining, fuel-sufficient, part of the Holocene. Our results also suggest that the occurrence of more frequent fires in the early Holocene has kept woodlands open, promoted grassland abundance and sustained a more flammable ecosystem (mFI < 150 years) whereas the decline in fire risk under cooler and wetter climate conditions (mFI = 317 years) favoured woodland development. From 3300 cal yr BP, human impacts clearly were partly responsible for changes in fire activity, first increasing fire frequency and severity in periods with fire-favourable climatic conditions (halving the mFI from 300 years to about 150 years), then effectively suppressing fires over the last several centuries. Given the projected future temperature increase and moisture decline and the biomass accumulation due to the agricultural land abandonment in the region, natural fire frequency would be expected to return to <150 years.
•First multi-proxy record and climate modelling of fire regime in CE Europe.•Strong influence of early summer temperature and moisture content on fire activity.•High sensitivity of fire activity to the short-lived climate events.•Frequent fires associated with open woodlands, whereas the decline in fire risk favoured woodland development.•Synergic influence of natural and human factors on fire frequency from 3300 BP.
The study examines terminological nominations in the IT sphere in the Russian, which include lexicon denoting ontological concepts. The aim of the research is to identify a conceptual shift in the ...perception of reality, as explicit in new terminological nominations of the digital era (augmented reality, mixed reality, RR). Composite nominations with key nouns of ontological semantics were extracted from scientific and media discourse. Research methodology includes semantic and contextual analysis, interpretative analysis within the framework of the theory of linguistic conceptualization of the world. The following conclusions were drawn: the use of words of ontological semantics in IT technical terms reflects a technocentric view of objective reality, where its fundamentally significant role in human and societal organization is reimagined. The concept of “reality” is juxtaposed with the concept of “virtuality.” The “real reality” itself, designated as ‘RR’, is considered one of the components in the paradigm of immersive technologies. Semantic changes are evident in the adjective ‘realnyy’ real: in opposition to attributes like ‘virtualnyy’ virtual, ‘onlayn’ online, etc., it embodies a new semantic nuance ‘manifesting not in virtual space’, which becomes relevant in discussions about the role of digital technologies in life.
The evolution of the concept of “virtual personality” relevant for the digital age (from diffuse to terminological) is considered. The means of its expression are analyzed. Research sources: personal ...websites and blogs of contemporary Russian authors, prose and philosophical texts. Electronic search databases were also involved: Russian National Corpus, the media bank “Integrum”. The objectives of the study are to define and describe the semantic structure of the term
virtual personality
; identify semantic connections with related nominations (network personality, digital personality; real personality); to establish possible transformations of the concept of “personality” in the digital age. The study was carried out using the methods of cognitive science and functional sociolinguistics. As a result: a model of a dictionary entry for the term
virtual personality
is presented (for the forthcoming dictionary of digital society terms). For the first time, a comparative analysis of the concepts of “virtual personality” and “digital personality” was carried out according to such criteria as intentional / unintentional, activity / passivity, subject / object of influence, presence / absence of (relative) freedom. A conclusion is proposed about the expansion of the semantics of the word
personality
in the context of digital technologies of the information society due to a new lexical-semantic variant: ‘a set of user data presented on the Web in digital format; digital footprint.
The synergistic antioxidant effect of different concentrations (50–250
ppm) of α-tocopherol and myricetin during autoxidation of triacylglycerols of sunflower oil (TGSO) at 100
°C was studied. The ...process was followed by monitoring the peroxide values and the formation of conjugated dienes. It was established that myricetin is a more effective and stronger antioxidant than α-tocopherol. All mixtures investigated exhibited a synergistic effect. The best synergistic effect was achieved with an equal molar ratio of α-tocopherol and myricetin, and at total concentration of the mixtures lower than 10
×
10
−4
M. The kinetic analysis of the results demonstrated that α-tocopherol regenerates myticetin during autoxidation of TGSO at 100
°C.
Pion–Muon separation with a RICH prototype for the NA62 experiment Angelucci, B.; Anzivino, G.; Avanzini, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2010, Letnik:
621, Številka:
1
Journal Article
Recenzirano
The NA62 experiment at CERN, aimed to measure
K
+
→
π
+
ν
ν
¯
branching fraction (O(10
−10)), relies on a Neon based RICH detector for
π
/
μ
separation, time measurement and level 0 trigger. The ...experimental requirements for this detector are: a muon contamination in pion samples lower than 5×10
−3 in the momentum range 15–35
GeV/
c and a time resolution on the charged track better than 100
ps. A prototype of such a detector was built and tested in 2009; it consists of a full length (
≈
18
m
) Ne filled vessel equipped with a spherical mirror and 414 PMs on its focal plane, located about 17
m upstream of the mirror. This prototype was tested at CERN SPS on a positive hadron beam, in the required momentum range, to measure the
π
/
μ
separation and to confirm the time resolution obtained with a previous prototype; the
μ
misidentification probability is about 0.7% and the time resolution is better than 100
ps in the whole momentum range.
Synthesis and characterization of new Pt(II) complexes of cyclohexanespiro-5-(2-thiohydantoin) (L1) and cycloheptanespiro-5-(2-thiohydantoin) (L2) are discussed. The new complexes are studied by ...elemental analysis, IR, ATR FTIR spectroscopy. The free ligands are investigated by UV-Vis, FT-IR, (1)H NMR, (13)C NMR and Raman spectroscopy. The ground-state equilibrium geometries of the ligands L1 and L2 and their complexes with Pt(II) are optimized at the BLYP/CEP-31G theoretical level.
The Tree Shelter and Sodmein Cave are two sites in the Egyptian Eastern Desert with stratified archaeological deposits. In Middle Holocene contexts of both sites, dated to the 7th millennium BP and ...later, animal dung has been found, in the shape of small concentrations of pellets at the Tree Shelter and of large accumulations at Sodmein Cave. The combination of several lines of evidence, including the size and weight of the excrements, the dimensions of the dung layers from Sodmein and the presence of hearths and artefacts inside them, and the species represented in the bone assemblages from Sodmein and the Tree Shelter, indicates that the dung was mostly deposited by herds of domestic ovicaprines. Sodmein Cave and the Tree Shelter belong to the oldest sites of the African continent where evidence for domestic small livestock has been attested. The importance and size of the herds seems to have been greater than would be suspected from the scant bone remains that were found. The visits to the caves were probably short but repeated over a long time period. Macrobotanical remains recovered from the dung suggest that these visits took place after seasonal winter rains.
The autoxidation of purified triacylglycerols of lard and sunflower oil (TGL and TGSO) containing 0.02, 0.05, 0.10 and 0.20% thymol and carvacrol was studied at ambient temperature. The results ...obtained with the inhibited lipid systems (thymol - TGL; carvacrol - TGL; thymol - TGSO and carvacrol - TGSO) showed that thymol had the highest antioxidant effectiveness and activity during TGSO oxidation. Thymol and carvacrol participated in one side reaction during inhibited TGL oxidation, and thymol took part in two side reactions during TGSO oxidation. Carvacrol molecules did not participate in side reactions during TGSO oxidation. Thymol and carvacrol contributed to chain initiation to a higher degree during TGSO oxidation than during TGL oxidation. Thymol radicals did not participate in chain propagation during TGL and TGSO oxidation. Carvacrol radicals took part in one reaction of chain propagation in both lipid systems. In general, during autoxidation of lipids at ambient temperature, thymol is a more effective and more active antioxidant than carvacrol. Both antioxidants differ in the mechanism of their inhibiting action which depends on the character of the lipid medium. Thymol is a better antioxidant in TGSO than in TGL, whereas the activity of carvacrol in the two lipid systems does not differ significantly.
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