72 resultados para Near Eastern Languages and Societies
Resumo:
This paper reviews the current state of development of both near-infrared (NIR) and mid-infrared (MIR) spectroscopic techniques for process monitoring, quality control, and authenticity determination in cheese processing. Infrared spectroscopy has been identified as an ideal process analytical technology tool, and recent publications have demonstrated the potential of both NIR and MIR spectroscopy, coupled with chemometric techniques, for monitoring coagulation, syneresis, and ripening as well as determination of authenticity, composition, sensory, and rheological parameters. Recent research is reviewed and compared on the basis of experimental design, spectroscopic and chemometric methods employed to assess the potential of infrared spectroscopy as a technology for improving process control and quality in cheese manufacture. Emerging research areas for these technologies, such as cheese authenticity and food chain traceability, are also discussed.
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There is disagreement about the routes taken by populations speaking Bantu languages as they expanded to cover much of sub-Saharan Africa. Here, we build phylogenetic trees of Bantu languages and map them onto geographical space in order to assess the likely pathway of expansion and test between dispersal scenarios. The results clearly support a scenario in which groups first moved south through the rainforest from a homeland somewhere near the Nigeria–Cameroon border. Emerging on the south side of the rainforest, one branch moved south and west. Another branch moved towards the Great Lakes, eventually giving rise to the monophyletic clade of East Bantu languages that inhabit East and Southeastern Africa. These phylogenies also reveal information about more general processes involved in the diversification of human populations into distinct ethnolinguistic groups. Our study reveals that Bantu languages show a latitudinal gradient in covering greater areas with increasing distance from the equator. Analyses suggest that this pattern reflects a true ecological relationship rather than merely being an artefact of shared history. The study shows how a phylogeographic approach can address questions relating to the specific histories of certain groups, as well as general cultural evolutionary processes.
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In the concluding paper of this tetralogy, we here use the different geomagnetic activity indices to reconstruct the near-Earth interplanetary magnetic field (IMF) and solar wind flow speed, as well as the open solar flux (OSF) from 1845 to the present day. The differences in how the various indices vary with near-Earth interplanetary parameters, which are here exploited to separate the effects of the IMF and solar wind speed, are shown to be statistically significant at the 93% level or above. Reconstructions are made using four combinations of different indices, compiled using different data and different algorithms, and the results are almost identical for all parameters. The correction to the aa index required is discussed by comparison with the Ap index from a more extensive network of mid-latitude stations. Data from the Helsinki magnetometer station is used to extend the aa index back to 1845 and the results confirmed by comparison with the nearby St Petersburg observatory. The optimum variations, using all available long-term geomagnetic indices, of the near-Earth IMF and solar wind speed, and of the open solar flux, are presented; all with ±2sigma� uncertainties computed using the Monte Carlo technique outlined in the earlier papers. The open solar flux variation derived is shown to be very similar indeed to that obtained using the method of Lockwood et al. (1999).
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Svalgaard (2014) has recently pointed out that the calibration of the Helsinki magnetic observatory’s H component variometer was probably in error in published data for the years 1866–1874.5 and that this makes the interdiurnal variation index based on daily means, IDV(1d), (Lockwood et al., 2013a), and the interplanetary magnetic field strength derived from it (Lockwood et al., 2013b), too low around the peak of solar cycle 11. We use data from the modern Nurmijarvi station, relatively close to the site of the original Helsinki Observatory, to confirm a 30% underestimation in this interval and hence our results are fully consistent with the correction derived by Svalgaard. We show that the best method for recalibration uses the Helsinki Ak(H) and aa indices and is accurate to ±10 %. This makes it preferable to recalibration using either the sunspot number or the diurnal range of geomagnetic activity which we find to be accurate to ±20 %. In the case of Helsinki data during cycle 11, the two recalibration methods produce very similar corrections which are here confirmed using newly digitised data from the nearby St Petersburg observatory and also using declination data from Helsinki. However, we show that the IDV index is, compared to later years, too similar to sunspot number before 1872, revealing independence of the two data series has been lost; either because the geomagnetic data used to compile IDV has been corrected using sunspot numbers, or vice versa, or both. We present corrected data sequences for both the IDV(1d) index and the reconstructed IMF (interplanetary magnetic field).We also analyse the relationship between the derived near-Earth IMF and the sunspot number and point out the relevance of the prior history of solar activity, in addition to the contemporaneous value, to estimating any “floor” value of the near-Earth interplanetary field.
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The sensitivity of the UK Universities Global Atmospheric Modelling Programme (UGAMP) General Circulation Model (UGCM) to two very different approaches to convective parametrization is described. Comparison is made between a Kuo scheme, which is constrained by large-scale moisture convergence, and a convective-adjustment scheme, which relaxes to observed thermodynamic states. Results from 360-day integrations with perpetual January conditions are used to describe the model's tropical time-mean climate and its variability. Both convection schemes give reasonable simulations of the time-mean climate, but the representation of the main modes of tropical variability is markedly different. The Kuo scheme has much weaker variance, confined to synoptic frequencies near 4 days, and a poor simulation of intraseasonal variability. In contrast, the convective-adjustment scheme has much more transient activity at all time-scales. The various aspects of the two schemes which might explain this difference are discussed. The particular closure on moisture convergence used in this version of the Kuo scheme is identified as being inappropriate.
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ATSR-2 active fire data from 1996 to 2000, TRMM VIRS fire counts from 1998 to 2000 and burn scars derived from SPOT VEGETATION ( the Global Burnt Area 2000 product) were mapped for Peru and Bolivia to analyse the spatial distribution of burning and its intra- and inter-annual variability. The fire season in the region mainly occurs between May and October; though some variation was found between the six broad habitat types analysed: desert, grassland, savanna, dry forest, moist forest and yungas (the forested valleys on the eastern slope of the Andes). Increased levels of burning were generally recorded in ATSR-2 and TRMM VIRS fire data in response to the 1997/1998 El Nino, but in some areas the El Nino effect was masked by the more marked influences of socio-economic change on land use and land cover. There were differences between the three global datasets: ATSR-2 under-recorded fires in ecosystems with low net primary productivities. This was because fires are set during the day in this region and, when fuel loads are low, burn out before the ATSR-2 overpass in the region which is between 02.45 h and 03.30 h. TRMM VIRS was able to detect these fires because its overpasses cover the entire diurnal range on a monthly basis. The GBA2000 product has significant errors of commission (particularly areas of shadow in the well-dissected eastern Andes) and omission (in the agricultural zone around Santa Cruz, Bolivia and in north-west Peru). Particular attention was paid to biomass burning in high-altitude grasslands, where fire is an important pastoral management technique. Fires and burn scars from Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) data for a range of years between 1987 and 2000 were mapped for areas around Parque Nacional Rio Abiseo (Peru) and Parque Nacional Carrasco (Bolivia). Burn scars mapped in the grasslands of these two areas indicate far more burning had taken place than either the fires or the burn scars derived from global datasets. Mean scar sizes are smaller and have a smaller range in size between years the in the study area in Peru (6.6-7.1 ha) than Bolivia (16.9-162.5 ha). Trends in biomass burning in the two highland areas can be explained in terms of the changing socio-economic environments and impacts of conservation. The mismatch between the spatial scale of biomass burning in the high-altitude grasslands and the sensors used to derive global fire products means that an entire component of the fire regime in the region studied is omitted, despite its importance in the farming systems on the Andes.
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We have integrated information on topography, geology and geomorphology with the results of targeted fieldwork in order to develop a chronology for the development of Lake Megafazzan, a giant lake that has periodically existed in the Fazzan Basin since the late Miocene. The development of the basin can be best understood by considering the main geological and geomorphological events that occurred thought Libya during this period and thus an overview of the palaeohydrology of all Libya is also presented. The origin of the Fazzan Basin appears to lie in the Late Miocene. At this time Libya was dominated by two large rivers systems that flowed into the Mediterranean Sea, the Sahabi River draining central and eastern Libya and the Wadi Nashu River draining much of western Libya. As the Miocene progressed the region become increasingly affected by volcanic activity on its northern and eastern margin that appears to have blocked the River Nashu in Late Miocene or early Messinian times forming a sizeable closed basin in the Fazzan within which proto-Lake Megafazzan would have developed during humid periods. The fall in base level associated with the Messinian desiccation of the Mediterranean Sea promoted down-cutting and extension of river systems throughout much of Libya. To the south of the proto Fazzan Basin the Sahabi River tributary know as Wadi Barjuj appears to have expanded its headwaters westwards. The channel now terminates at Al Haruj al Aswad. We interpret this as a suggestion that Wadi Barjuj was blocked by the progressive development of Al Haruj al Aswad. K/Ar dating of lava flows suggests that this occurred between 4 and 2 Ma. This event would have increased the size of the closed basin in the Fazzan by about half, producing a catchment close to its current size (-350,000 km(2)). The Fazzan Basin contains a wealth of Pleistocene to recent palaeolake sediment outcrops and shorelines. Dating of these features demonstrates evidence of lacustrine conditions during numerous interglacials spanning a period greater than 420 ka. The middle to late Pleistocene interglacials were humid enough to produce a giant lake of about 135,000 km(2) that we have called Lake Megafazzan. Later lake phases were smaller, the interglacials less humid, developing lakes of a few thousand square kilometres. In parallel with these palaeohydrological developments in the Fazzan Basin, change was occurring in other parts of Libya. The Lower Pliocene sea level rise caused sediments to infill much of the Messinian channel system. As this was occurring, subsidence in the Al Kufrah Basin caused expansion of the Al Kufrah River system at the expense of the River Sahabi. By the Pleistocene, the Al Kufrah River dominated the palaeohydrology of eastern Libya and had developed a very large inland delta in its northern reaches that exhibited a complex distributary channel network which at times fed substantial lakes in the Sirt Basin. At this time Libya was a veritable lake district during humid periods with about 10% of the country underwater. (C) 2008 Elsevier B.V. All rights reserved.
Resumo:
Radiocarbon (carbon-14) data from the Aegean Bronze Age 1700-1400 B.C. show that the Santorini (Thera) eruption must have occurred in the late 17th century B.C. By using carbon-14 dates from the surrounding region, cultural phases, and Bayesian statistical analysis, we established a chronology for the initial Aegean Late Bronze Age cultural phases (Late Minoan IA, IB, and II). This chronology contrasts with conventional archaeological dates and cultural synthesis: stretching out the Late Minoan IA, IB, and II phases by similar to 100 years and requiring reassessment of standard interpretations of associations between the Egyptian and Near Eastern historical dates and phases and those in the Aegean and Cyprus in the mid-second millennium B.C.
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The origins of farming is the defining event of human history-the one turning point that has resulted in modern humans having a quite different type of lifestyle and cognition to all other animals and past types of humans. With the economic basis provided by farming, human individuals and societies have developed types of material culture that greatly augment powers of memory and computation, extending the human mental capacity far beyond that which the brain alone can provide. Archaeologists have long debated and discussed why people began living in settled communities and became dependent on cultivated plants and animals, which soon evolved into domesticated forms. One of the most intriguing explanations was proposed more than 20 years ago not by an archaeologist but by a psychologist: Nicholas Humphrey suggested that farming arose from the 'misapplication of social intelligence'. I explore this idea in relation to recent discoveries and archaeological interpretations in the Near East, arguing that social intelligence has indeed played a key role in the origin of farming and hence the emergence of the modern world.
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The El Niño–Southern Oscillation (ENSO) is a naturally occurring fluctuation that originates in the tropical Pacific region and affects ecosystems, agriculture, freshwater supplies, hurricanes and other severe weather events worldwide. Under the influence of global warming, the mean climate of the Pacific region will probably undergo significant changes. The tropical easterly trade winds are expected to weaken; surface ocean temperatures are expected to warm fastest near the equator and more slowly farther away; the equatorial thermocline that marks the transition between the wind-mixed upper ocean and deeper layers is expected to shoal; and the temperature gradients across the thermocline are expected to become steeper. Year-to-year ENSO variability is controlled by a delicate balance of amplifying and damping feedbacks, and one or more of the physical processes that are responsible for determining the characteristics of ENSO will probably be modified by climate change. Therefore, despite considerable progress in our understanding of the impact of climate change on many of the processes that contribute to El Niño variability, it is not yet possible to say whether ENSO activity will be enhanced or damped, or if the frequency of events will change.
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Intercontinental Transport of Ozone and Precursors (ITOP) (part of International Consortium for Atmospheric Research on Transport and Transformation (ICARTT)) was an intense research effort to measure long-range transport of pollution across the North Atlantic and its impact on O3 production. During the aircraft campaign plumes were encountered containing large concentrations of CO plus other tracers and aerosols from forest fires in Alaska and Canada. A chemical transport model, p-TOMCAT, and new biomass burning emissions inventories are used to study the emissions long-range transport and their impact on the troposphere O3 budget. The fire plume structure is modeled well over long distances until it encounters convection over Europe. The CO values within the simulated plumes closely match aircraft measurements near North America and over the Atlantic and have good agreement with MOPITT CO data. O3 and NOx values were initially too great in the model plumes. However, by including additional vertical mixing of O3 above the fires, and using a lower NO2/CO emission ratio (0.008) for boreal fires, O3 concentrations are reduced closer to aircraft measurements, with NO2 closer to SCIAMACHY data. Too little PAN is produced within the simulated plumes, and our VOC scheme's simplicity may be another reason for O3 and NOx model-data discrepancies. In the p-TOMCAT simulations the fire emissions lead to increased tropospheric O3 over North America, the north Atlantic and western Europe from photochemical production and transport. The increased O3 over the Northern Hemisphere in the simulations reaches a peak in July 2004 in the range 2.0 to 6.2 Tg over a baseline of about 150 Tg.
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This paper presents recent research into the functions and value of sketch outputs during computer supported collaborative design. Sketches made primarily exploiting whiteboard technology are shown to support subjects engaged in remote collaborative design, particularly when constructed in ‘nearsynchronous’ communication. The authors define near-synchronous communication and speculate that it is compatible with the reflective and iterative nature of design activity. There appears to be significant similarities between the making of sketches in near-synchronous remote collaborative design and those made on paper in more traditional face-to-face settings With the current increase in the use of computer supported collaborative working (CSCW) in undergraduate and postgraduate design education it is proposed that sketches and sketching can make important contributions to design learning in this context
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Sires of seven Bos taurus beef breeds were mated with Bos indicus Boran cows at two sites, one near sea level and the other at about 1000 m altitude, and over three years. Purebred Boran calves provided controls for comparisons between sire breeds for growth to 4 years of age, mortality and carcase characteristics in a range environment where all the animals were kept under a similar management regime. Numerous sire breed x site, sire breed x year of birth and site x year of birth interactions were established. Mortality was high, but there was no significant sire breed effect, although purebred Borans had a higher survival than crossbred calves. There was no significant difference between genotypes in birth weight. Generally, Bos taurus cross steers achieved greater live weight gains and heavier carcase weights at 4 years of age than did purebred Borans. Limousin-cross steers had significantly (p<0.05) less fat in the tenth rib sample joint than any of the other genotypes. A productivity index that combined calf survival and carcase weight indicated that the Chianina crosses were more productive than any other genotype at either site. Purebred Borans were more productive than all the Bos taurus crossbreds with the exception of the Chianina crosses at site 1, but were only superior to the Limousin crosses at site 2, which was at the higher altitude. When lean meat yield was introduced into the productivity index, the Boran purebreds were the least productive at site 2.
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A recent phylogenetic study based on multiple datasets is used as the framework for a more detailed examination of one of the ten molecularly circumscribed groups identified, the Ophrys fuciflora aggregate. The group is highly morphologically variable, prone to phenotypic convergence, shows low levels of sequence divergence and contains an unusually large proportion of threatened taxa, including the rarest Ophrys species in the UK. The aims of this study were to (a) circumscribe minimum resolvable genetically distinct entities within the O. fuciflora aggregate, and (b) assess the likelihood of gene flow between genetically and geographically distinct entities at the species and population levels. Fifty-five accessions sampled in Europe and Asia Minor from the O. fuciflora aggregate were studied using the AFLP genetic fingerprinting technique to evaluate levels of infraspecific and interspecific genetic variation and to assess genetic relationships between UK populations of O. fuciflora s.s. in Kent and in their continental European and Mediterranean counterparts. The two genetically and geographically distinct groups recovered, one located in England and central Europe and one in south-eastern Europe, are incongruent with current species delimitation within the aggregate as a whole and also within O. fuciflora s.s. Genetic diversity is higher in Kent than in the rest of western and central Europe. Gene flow is more likely to occur between populations in closer geographical proximity than those that are morphologically more similar. Little if any gene flow occurs between populations located in the south-eastern Mediterranean and those dispersed throughout the remainder of the distribution, revealing a genetic discontinuity that runs north-south through the Adriatic. This discontinuity is also evident in other clades of Ophrys and is tentatively attributed to the long-term influence of prevailing winds on the long-distance distribution of pollinia and especially seeds. A cline of gene flow connects populations from Kent and central and southern Europe; these individuals should therefore be considered part of an extensive meta-population. Gene flow is also evident among populations from Kent, which appear to constitute a single metapopulation. They show some evidence of hybridization, and possibly also introgression, with O. apifera.
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In the title family, the ONO donor ligands are the acetylhydrazones of salicylaidehyde (H2L1) and 2-hydroxyacetophenone (H2L2) (general abbreviation, H2L). The reaction of bis(acetylacetonato)oxovanadium(IV) with a mixture of tridentate H2L and a bidentate NN donor [e.g., 2,2'-bipyridine(bpy) or 1,10-phenanthroline(phen), hereafter B] ligands in equimolar ratio afforded the tetravalent complexes of the type [(VO)-O-IV(L)(B)]; complexes (1)-(4) whereas, if B is replaced by 8-hydroxyquinoline(Hhq) (which is a bidentate ON donor ligand), the above reaction mixture yielded the pentavalent complexes of the type [(VO)-O-V(L)(hq)]; complexes (5) and (6). Aerial oxygen is most likely the oxidant (for the oxidation of V-IV -> V-V) in the synthesis of pentavalent complexes (5) and (6). [(VO)-O-IV(L)(B)] complexes are one electron paramagnetic and display axial EPR spectra, while the [(VO)-O-V(L)(hq)] complexes are diamagnetic. The X-ray structure of [(VO)-O-V(L-2)(hq)] (6) indicates that H2L2 ligand is bonded with the vanadium meridionally in a tridentate dinegative fashion through its phenolic-O, enolic-O and imine-N atoms. The general bond length order is: oxo < phenolato < enolato. The V-O (enolato) bond is longer than V-O (phenolato) bond by similar to 0.07 angstrom and is identical with V-O (carboxylate) bond. H-1 NMR spectrum of (6) in CDCl3 solution indicates that the binding nature in the solid state is also retained in solution. Complexes (1)(4) display two ligand-field transitions in the visible region near 820 and 480 nm in DMF solution and exhibit irreversible oxidation peak near +0.60 V versus SCE in DMSO solution, while complexes (5) and (6) exhibit only LMCT band near 535 nm and display quasi-reversible one electron reduction peak near -0.10 V versus SCE in CH2Cl2 solution. The VO3+-VO2+ E-1/2 values shift considerably to more negative values when neutral NN donor is replaced by anionic ON donor species and it also provides better VO3+ binding via phenolato oxygen. For a given bidentate ligand, E-1/2 increases in the order: (L-2)(2-) < (L-1)(2-). (c) 2004 Elsevier B.V. All rights reserved.