1,314 research outputs found
The Contribution of Bering Sea Water to the Arctic Ocean
Summarizes the characteristics, especially temperature-salinity of these waters as they flow north through Bering Strait, and as they modify the surface water, deeper water, and ice cover of the western Arctic Ocean. Analysis of about 200 deep-water stations reveals regularity in the vertical distribution of temperature and salinity. The shallow 75-100 m depth, temperature maximum observed in the western as distinct from the eastern Arctic Basin is maintained by advection from some external source, in part the flow through the Strait. Bering Sea water apparently flows north into Chukchi Sea, where it mixes with Siberian shelf water then joins the general circulation in the area northwest of Point Barrow. The intruding Bering Sea water separates deeper Atlantic water from Arctic Ocean surface water; this Bering water may be traced by the shallow temperature maximum; but it affects ice conditions in the Basin very little
The Movement of Atlantic Water in the Arctic Ocean
Re-evaluates sixty years' oceanographic data from the Arctic Ocean, examining nearly 300 deep-water stations, and using the "core-layer" method of Wust to interpret the movement of the Atlantic layer. Stations are grouped in 16 areas and the average curve for each group plotted on a temperature-salinity diagram. Temperature and salinity changes which take place in the Atlantic water while and entity in the Arctic Basin are graphed. The temperature maximum is reduced by about 3.5 C, and the salinity at max. temperature is reduced by about 0.2 %. Superimposed on the T-S relationship is an arbitrary scale indicating percentage retention of the original characteristics. The velocity of the Atlantic layer is found (from current velocity, eddy coefficients and station data) to range 1-10 cm/sec and values of Kz (vertical eddy coefficient) generally to range 1-20 sq cm/sec. Percentage retention of characteristics from the T-S diagram is mapped to suggest a relation between the flow of Atlantic water and bathymetry, distance, time, as well as the T-S features. Assuming the velocity along the core to be 3 cm/sec, the constant vertical eddy coefficient to be 10 sq cm/sec, and with other assumptions on temperature distribution, an estimate of 8,000,000 sq cm/sec is obtained for the constant lateral eddy coefficient
Surface Water in the Eurasian Basin of the Arctic Ocean
Reports results of re-appraisal and interpretation of data from 74 oceanographic stations (of >400 occupied), listed according to vessel and source. Surface water occupies the uppermost 200 m It is almost continuously supplied by continental runoff from Siberia which mixes with and collects saline water, to a few hundred times its original volume, as it crosses the arctic shelf seas. The surface water then flows directly to the exit from the basin between Spitsbergen and Greenland. Three layers of surface water are distinguished, on the basis of temperature and salinity features. Variations and ranges within each layer are thought the result of geographic location, presence of ice cover, seasonal changes, convection , and advection. Lowest layer, from 100 m down to the Atlantic water, shows evidence of mixing with the subsurface layer, as well as evidence of continuous replenishment. Prevalence of the cold subsurface layer in this basin is explained by a proposed model, which recognizes the submarine canyons, notably the Svyataya Anna in the Kara Sea, as important factors in mixing and cooling and as primary sources of subsurface water
Розвиток мотивації учіння студентів в контексті активізації навчання
В статье рассматриваются основные теоретические положения формирования мотивации учения студентов, определены уровни развития мотивации учения, а также дано их психолого-педагогическое обоснование.The article deals with fundamental theoretical statements in the sphere of formation of students’ learning motivation, the levels of formation of students’ learning motivation are defined and also their psychological and pedagogical argumentation is given
The Aging Navigational System
The discovery of neuronal systems dedicated to computing spatial information, composed of functionally distinct cell types such as place and grid cells, combined with an extensive body of human-based behavioral and neuroimaging research has provided us with a detailed understanding of the brain's navigation circuit. In this review, we discuss emerging evidence from rodents, non-human primates, and humans that demonstrates how cognitive aging affects the navigational computations supported by these systems. Critically, we show 1) that navigational deficits cannot solely be explained by general deficits in learning and memory, 2) that there is no uniform decline across different navigational computations, and 3) that navigational deficits might be sensitive markers for impending pathological decline. Following an introduction to the mechanisms underlying spatial navigation and how they relate to general processes of learning and memory, the review discusses how aging affects the perception and integration of spatial information, the creation and storage of memory traces for spatial information, and the use of spatial information during navigational behavior. The closing section highlights the clinical potential of behavioral and neural markers of spatial navigation, with a particular emphasis on neurodegenerative disorders
Energy Loss, Electron Screening, and the Astrophysical 3He(d,p)4He cross section
We reanalyze the low-energy 3He(d,p)4He cross section measurements of
Engstler et al. using recently measured energy loss data for proton and
deuteron beams in a helium gas. Although the new 3He(d,p)4He S-factors are
significantly lower than those reported by Engstler et al. they clearly show
the presence of electron screening effects. From the new S-factors we find an
electron screening energy in agreement with the adiabatic limit.Comment: 8 Page RevTeX document, two postscript figures, now in a
self-extracting uufile type archiv
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The impact of EU commercial fisheries policies and practice on international trade in fisheries products. Final report
Towards a novel carbon device for the treatment of sepsis
Sepsis is a systemic inflammatory response to infection in which the balance of pro- andanti-inflammatory mediators, which normally isolate and eliminate infection, is disrupted[1]. Gram negative sepsis is initiated by bacterial endotoxin release which activatesmacrophages and circulating monocytes to release TNF and IL-1β followed by IL-6 andother inflammatory cytokines [2]. As the disease progresses, an unregulatedinflammatory response results in, tissue injury, haematological dysfunction and organdysfunction. Severe sepsis, involving organ hypoperfusion may be further complicatedby hypotension that is unresponsive to adequate fluid replacement, resulting in septicshock and finally death [3].Despite improvements in anti-microbial and supportive therapies, sepsis remains asignificant cause of morbidity and mortality in ICUs worldwide [4]. The complexity ofprocesses mediating the progression of sepsis suggests that an extracorporeal devicecombining blood filtration with adsorption of a wide range of toxins, and inflammatorymediators offers the most comprehensive treatment strategy. However, no such deviceexists at present. A novel, uncoated, polymer pyrolysed synthetic carbon device isproposed which combines the superior adsorption properties of uncoated activatedcarbons with the capacity to manipulate porous structure for controlled adsorption oftarget plasma proteins and polypeptides [5]. Preliminary haemocompatibility andadsorptive capacity was assessed using a carbon matrix prototype
Roche tomography of cataclysmic variables: I. artefacts and techniques
Roche tomography is a technique used for imaging the Roche-lobe filling
secondary stars in cataclysmic variables (CVs). In order to interpret Roche
tomograms correctly, one must determine whether features in the reconstruction
are real, or due to statistical or systematic errors. We explore the effects of
systematic errors using reconstructions of simulated datasets and show that
systematic errors result in characteristic distortions of the final
reconstructions that can be identified and corrected. In addition, we present a
new method of estimating statistical errors on tomographic reconstructions
using a Monte-Carlo bootstrapping algorithm and show this method to be much
more reliable than Monte-Carlo methods which `jiggle' the data points in
accordance with the size of their error bars.Comment: 11 pages, 8 figures. Accepted for publication in MNRA
The contribution of qualitative behavioural assessment to appraisal of livestock welfare
Animal welfare is increasingly important for the Australian livestock industries, to maintain social licence to practice as well as ensuring market share overseas. Improvement of animal welfare in the livestock industries requires several important key steps. Paramount among these, objective measures are needed for welfare assessment that will enable comparison and contrast of welfare implications of husbandry procedures or housing options. Such measures need to be versatile (can be applied under a wide range of on- and off-farm situations), relevant (reveal aspects of the animal’s affective or physiological state that is relevant to their welfare), reliable (can be repeated with confidence in the results), relatively economic to apply, and they need to have broad acceptance by all stakeholders. Qualitative Behavioural Assessment (QBA) is an integrated measure that characterises behaviour as a dynamic, expressive body language. QBA is a versatile tool requiring little specialist equipment suiting application to in situ assessments that enables comparative, hypothesis-driven evaluation of various industry-relevant practices. QBA is being increasingly used as part of animal welfare assessments in Europe, and although most other welfare assessment methods record ‘problems’ (e.g. lameness, injury scores, and so on), QBA can capture positive aspects of animal welfare (e.g. positively engaged with their environment, playfulness). In this viewpoint, we review the outcomes of recent QBA studies and discuss the potential application of QBA, in combination with other methods, as a welfare assessment tool for the Australian livestock industries
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