197,192 research outputs found
Role of tephra in dating Polynesian settlement and impact, New Zealand
No full textTephrochronology in its original sense is the use of tephra layers as time-stratigraphic marker beds to establish numerical or relative ages (Lowe and Hunt, 2001). Tephra layers have been described and studied in New Zealand for more than 160 years (the German naturalist and surgeon Ernst Dieffenbach described ‘recognizable’ tephra sections in his 1843 book Travels in New Zealand), and the first isopach map, showing fallout from the deadly plinian basaltic eruption of Mt Tarawera on 10 June 1886, was published in 1888 (Lowe, 1990; Lowe et al., 2002). More recently, a wide range of tephra-related paleoenvironmental research has been undertaken (e.g., Lowe and Newnham, 1999; Newnham and Lowe, 1999; Newnham et al., 1999, 2004; Shane, 2000), including new advances in the role of tephra in linking and dating sites containing evidence for abrupt climatic change (e.g., Newnham and Lowe, 2000; Newnham et al., 2003). Here we focus on the use of tephrochronology in dating the arrival and impacts of the first humans in New Zealand, a difficult problem for which this technique has proven to be of critical importance
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Further Investigations at 34-38 Newnham Road, Cambridge
No full textAn on-going watching brief of building excavations beneath an area of new wall being undertaken at nos. 34-38 Newnham Road during February 2006 provided further evidence of the nature and extent of a medieval pond in the backyard, whilst at the level of a mid-late 18th century ‘cellar’ (beneath no.36a) building excavations had exposed the foundations for what were in all probability a series of 17th century tenements fronting Newnham Road (Newnham High Street). An archaeological test pit revealed a still earlier floor surface underlying the levelling/make-up layers for these brick buildings which might relate to a 16th century or earlier timbered house. Below this a layer of garden soil containing sherds of 15th century coarseware suggested a still earlier phase of intensive backyard cultivation, perhaps associated with medieval dwellings on Maltings Lane (Froshlake Way) or Elde Newenham Weye (Newnham Road). Behind this area of garden, the large pond (up to 2.5 m deep) may originally have been excavated as a gravel pit, then flooded and used as a fishpond, perhaps associated with the nearby Mortimer’s (Newnham) Mill, or the fishponds adjacent to the mill dam leased by St. John’s Hospital. Evidence for some sort of sophisticated water management here has turned up in the form of (lain?) sections of probable 15th century (Ely Ware) ceramic water pipe – a potentially important find. In addition, some well preserved but probably broken and therefore discarded fragments of a ?15th century leather shoe were recovered from the base of the pond
Palaeolimnology of Adelaide Tarn, a ~14,000-year-old low-alpine glacial lake, northwestern South Island, New Zealand
No full textA palaeolimnology study has been carried out on a ~14,000 calendar [cal]-year-old low-alpine glacial lake, Adelaide Tarn. The lake is located in a cirque basin at ~1260 m elevation in the Tasman Mountains, just below present-day treeline, within Kahurangi National Park, northern South Island, New Zealand. A 5.6-m long sediment core was retrieved from the lake by staff of GNS Science. The chronology of the core was constructed from 15 ¹⁴C dates obtained via AMS on 14 samples of in-situ plant macrofossils and one sample of bulk organic sediment. The core was divided into lithozones 1, 2, and 3 from the base through to the top of the core. Lithozone 1 (5.6–4.8 m) comprises inorganic (carbon content 0.3 to 4%) grey silts with gravel (Munsell colour 5Y 6/1) and these sediments, primarily composed of angular particles identifed by scanning electron microscopy (SEM), date to a little earlier than ~13,932 cal yr BP. Lithozone 2 consists of organic (carbon content up to 15%) brownish black (10YR 2/3) silt and clay and extends from ~13,932 to ~7709 cal yr BP. In lithozone 2, diatoms appear, as identified by SEM. Lithozone 3 is made up of dark brown (10YR 3/4) organic silt (carbon content 5 to 10%) and extends from ~7709 cal yr BP through to the top of the core which has an age estimated to be a little older than ~700 cal yr BP on the basis of a ¹⁴C date (~926 cal yr BP) at 13 cm depth and a pollen record that shows neither a Polynesian deforestation signal (i.e. the sediments likely pre-date ~700 cal yr BP) nor European adventives (i.e. the sediments pre-date ~1840 AD). Lithozone 3 is diatom-rich with subordinate angular particles. Intermittent yellow/brown (10YR 6/8) laminae occur throughout lithozones 2 and 3; one lamination occurs near the top of lithozone 1. These yellow/brown laminae comprise mainly angular clastic particles (evident in SEM micrographs) and show a slight increase in sand compared with non-laminated sediments, and the laminae are inferred to reflect terrigenous input to the lake as a consequence of storms or during intense rainfall events. These possible storm events may correspond with ENSO events as described/identified in Lake Tutira in Hawke’s Bay.
Multiple components of the sediment archive were analysed to reconstruct the history of the lake and its catchment. Properties included were X-radiography, grey-scale, magnetic susceptibility, grain size, plant macrofossil assemblages, organic carbon content, and isotopes δ¹⁵N and δ¹³C.
The results show four phases of climate variability (Adelaide Tarn climate events, AT-CEs) from the onset of lake formation ~14,000 cal yr BP. AT-CE1: early sediments ~14,000 cal yr BP show enhanced terrigenous input (fine-grained grey silts, with gravel layers, of lithozone 1), consistent with fluvio-glacial in-wash during retreat from the Adelaide Tarn basin of a local cirque glacier. AT-CE2: from ~13,932 to ~10,000 cal yr BP, erosion of the catchment is much diminished, indicated by decreases in modal grain size and magnetic susceptibility, and lake productivity concomitantly commences as shown by the δ¹³C and δ¹⁵N isotope records. Poaceae species dominate the macrofossil plant assemblages with no tree-species found. AT-CE2 (~13,932 to ~10,000 cal yr BP) is inferred to be one of warming but the catchment was not yet stable and little or no soil formation occurred that would allow habitation by tree species. AT-CE3: the third palaeoenvironmental phase, from ~10,000 to ~2400 cal yr BP, is marked by an expansion of Nothofagus (Nothofagus menziesii and Nothofagus fusca) forest with minor constituents of Libocedrus biwillii and Phyllocladus alpinus. This phase is inferred to be one of sustained warm conditions and a stable catchment. Adelaide Tarn is situated 250 m higher than the present-day altitudinal limit of N. fusca and the presence of macrofossils of this species in the sediment record suggests that between ~6400 and ~2400 cal yr BP the mean annual temperature was possibly ~1.2˚C warmer than present based on an observed environmental lapse rate of 0.47˚C/100 m. There was slight increase in denitrification from ~8000 through to ~3000 cal yr BP, suggesting that primary productivity increased in the lake. AT-CE4: from ~2400 cal yr BP, the fourth phase, the plant assemblage shifted to Poaceae-dominated; cold-sensitive taxa were forced to descend, marked by disappearance of forest species from the plant macrofossil assemblage. The climate is inferred to have deteriorated and the tree-line descended to near the present-day position.
The Adelaide Tarn record is one of only a few spanning the last ~14,000 years in central New Zealand, and is especially useful in adding to the plant macrofossil records, which are rare. The Adelaide Tarn record was compared with the newly-published New Zealand climate event stratigraphy (NZ-CES), with the proposed tripartite subdivision of the Holocene, and with a number of records across New Zealand that are based on various proxies including speleothems and pollen assemblages. None of the NZ-CES events were clearly evident in the Adelaide Tarn record (apart from NZce-1), and the proposed boundaries of the subdivided Holocene (at ~8.2 ka and 4.2 ka) were not evident. A palynological record spanning the last ~12,000 years from Cropp Valley, western South Island, showed close consistency with the Adelaide Tarn record
Basic Spatial Units (BSU) at 250 m resolution for national ecosystem accounts
No full textThis data collection comprises spatial data for all accounts. It includes the 250 m resolution BSU in GDA94 / Australian Albers (EPSG:3577) projection, the coverage fraction of each pixel of the Ecosystem Accounting Area (EAA), and a “terrestrial” mask derived from the national land use data. A BSU is a geometric construct that represents the minimum unit of spatial aggregation for accounting. It was devised in agreement with ABS to create national ecosystem accounts. \nSee methods report in the Related Links for more detail on the BSU. \nLineage: Refer to methods (see Related Links):\nLiu N, Newnham G, Richards AE, Pascoe S, Tetreault Campbell S and Schmidt RK (2024) Methods for developing the 250 m resolution Basic Spatial Units (BSU) for national ecosystem accounts. A report for the National Ecosystem Accounting Project. CSIRO, Australia. https://doi.org/10.25919/3r5x-pg8
Fetal Sex and Preterm Birth
No full textRates of preterm birth vary between different populations and ethnic groups. Epidemiologic studies have suggested that the incidence of preterm birth is also higher in pregnancies carrying a male fetus; the male:female difference is greater in earlier preterm pregnancy. Placental or chorion trophoblast cells from pregnancies with a male fetus produced more pro-inflammatory TNFα in response to LPS stimulation and less anti-inflammatory IL-10 and granulocyte colony stimulating factor (G-CSF) than cells from pregnancies with a female fetus, more prostaglandin synthase (PTGS-2) and less prostaglandin dehydrogenase (PGDH). These results suggest that in the presence of a male fetus the trophoblast has the potential to generate a more pro-inflammatory environment. Maturation of the fetal hypothalamic-pituitary-adrenal axis and expression of placental genes, particularly 11β hydroxysteroid dehydrogenase-2 are also expressed in a sex dependent manner, consistent with the sex-biasing influences on gene networks. Sex differences in these activities may affect clinical outcomes of pre- and post-dates pregnancies and fetal/newborn wellbeing. These factors need consideration in studies of placental function and in the development of personalized strategies for the diagnosis of preterm labor and postnatal healt
Facilitating the “Elite†in innovation acquisition: an overrated concept or, a necessity?
No full textInnovation is a term that features in more than 40 000 web searches. Innovation is often confused with other terms such as creativity. Scott (2012) maintains that creativity is only part of the process of innovation. Educating the youth for tomorrows' world requires harnessing innovative measures where theoretical concepts are woven into the practical every-day (Newnham, 2015; Virkkunen, Newnham, Nleya & Engestrà¶m, 2012; Miettinen, 2005, 2009) and that of our tomorrow land. Christensen and Overdorf (2000) developed the concept of disruptive innovations. They state that disruptive innovations are derived from disruptive technologies. Disruptive innovations are those that have a new use or exchange value (Ollman, 2003) and eventually disrupt an existing practice and its value network.
Whilst developed nation states attempt to contend with the disruption of ICT's use in learning spaces, developing countries attempt to catch up to the international models of education.
Morocco's education mission and vision has not produced the desired outcomes and a new coalition with USAID had been drawn up until 2020. New strategies are being designed to overcome existing problems such as levels of illiteracy, dropout rate and student motivation. This text explores the possibilities of innovative models of education and provides concrete suggestions from noted scholars in the field
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34-38 Newnham Road, Cambridge. An Archaeological Evaluation
No full textAn archaeological investigation was conducted at 34 and 36a Newnham Road (properties of Clare College) from 4th to 11th January 2006. Two archaeological test pits were excavated within the yard area to the rear of the building, whilst two previously dug engineering test pits were examined and recorded within its interior. Archaeological features, perhaps different parts of the same large pit were identified within each of the two test pits in the yard; one of these proved to be more than 2.5 m deep and contained layers of dumped sand, lime/clunch, burnt sedge and other organic material suggesting use as a refuse or cess pit. These deposits contained pottery dating from the 14th to the 16th century associated with layers of waterlogged silt and preserved organics consisting of straw, moss, bone, oyster and mussel shell. Within the pit were found large amounts of burnt sedge fuel and charred cereal threshing waste – the latter perhaps the discarded contents of medieval bread ovens. The infilling of this feature from the north-east suggests that occupation refuse was then coming from an area of settlement around the current Malting Lane and Newnham House – formerly the location of Mortimer Manor and associated medieval tenancies. Beneath the foundations of the currently standing 19th century buildings, two engineering test pits revealed the brick footings for what were probably once 17th century dwellings
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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