333 research outputs found
E-Commerce as a Competitive Advantage for Small Businesses: Overcoming Privacy and Security Issues
The Internet and the World Wide Web (WWW) trend have captivated people in every corner of the world. The presence of both individuals and businesses on the Internet grows every day. For example, in 1998 businesses\u27 presence on the Internet grew so much that many described 1998 as the .com year. But why is it that the Internet is so attractive to all of us? The reason lies in the ease of use of the Internet, the speed of obtaining results, the amount of information available, and the global reach that the Internet has. For all these reasons, the Internet has become one of the most important marketing strategies available. By publishing information on the WWW, small businesses now have the opportunity to reach millions of people around the world, and more importantly, they can do so for a fraction of the cost of other advertising methods.
So where is e-commerce headed? One of the arguments is that small businesses will move to one-to-one marketing, where small businesses solicit demographic data to offer customized customer service and sales. This will not only increase sales by targeting the right sectors, but also by offering individualized service to current customers. Others argue that e-commerce\u27s global nature will force small businesses to better identify their core competencies to be able to compete in the global market place. One way or another, small businesses are using e-commerce to please the web customer who wants reliable and accurate information about products and services any time, any where and at no cost
Quantifying and monitoring functional Photosystem II and the stoichiometry of the two photosystems in leaf segments: Approaches and approximations
Given its unique function in light-induced
water oxidation and its susceptibility to photoinactivation
during photosynthesis, photosystem II (PS II) is often the
focus of studies of photosynthetic structure and function,
particularly in environmental stress conditions. Here we
review four approaches for quantifying or monitoring PS II
functionality or the stoichiometry of the two photosystems
in leaf segments, scrutinizing the approximations in each
approach. (1) Chlorophyll fluorescence parameters are
convenient to derive, but the information-rich signal suffers
from the localized nature of its detection in leaf tissue. (2)
The gross O2 yield per single-turnover flash in CO2-enriched
air is a more direct measurement of the functional
content, assuming that each functional PS II evolves one
O2 molecule after four flashes. However, the gross O2 yield
per single-turnover flash (multiplied by four) could overestimate
the content of functional PS II if mitochondrial
respiration is lower in flash illumination than in darkness.
(3) The cumulative delivery of electrons from PS II to P700? (oxidized primary donor in PS I) after a flash is
added to steady background far-red light is a whole-tissue
measurement, such that a single linear correlation with
functional PS II applies to leaves of all plant species
investigated so far. However, the magnitude obtained in a
simple analysis (with the signal normalized to the maximum
photo-oxidizable P700 signal), which should equal
the ratio of PS II to PS I centers, was too small to match the
independently-obtained photosystem stoichiometry. Further,
an under-estimation of functional PS II content could
occur if some electrons were intercepted before reaching
PS I. (4) The electrochromic signal from leaf segments
appears to reliably quantify the photosystem stoichiometry,
either by progressively photoinactivating PS II or suppressing
PS I via photo-oxidation of a known fraction of
the P700 with steady far-red light. Together, these
approaches have the potential for quantitatively probing PS
II in vivo in leaf segments, with prospects for application
of the latter two approaches in the field
Effect of Cold Hardening on the Components of Respiratory Decarboxylation in the Light and in the Dark in Leaves of Winter Rye
Predicting Light Acclimation in Cyanobacteria from Nonphotochemical Quenching of Photosystem II Fluorescence, Which Reflects State Transitions in These Organisms
Low-Temperature Effects on Photosynthesis and Correlation with Freezing Tolerance in Spring and Winter Cultivars of Wheat and Rye
Current forest carbon fixation fuels stream CO2 emissions
Stream CO2 emissions contribute significantly to atmospheric climate forcing. While there are strong indications that groundwater inputs sustain these emissions, the specific biogeochemical pathways and timescales involved in this lateral CO2 export are still obscure. Here, via an extensive radiocarbon (14C) characterisation of CO2 and DOC in stream water and its groundwater sources in an old-growth boreal forest, we demonstrate that the 14C-CO2 is consistently in tune with the current atmospheric 14C-CO2 level and shows little association with the 14C-DOC in the same waters. Our findings thus indicate that stream CO2 emissions act as a shortcut that returns CO2 recently fixed by the forest vegetation to the atmosphere. Our results expose a positive feedback mechanism within the C budget of forested catchments, where stream CO2 emissions will be highly sensitive to changes in forest C allocation patterns associated with climate and land-use changes
When does the action start and finish? Making the case for an ethnographic action research in educational research
This paper explores how ethnographic and action research methodologies can be justifiably combined to create a new methodological approach in educational research. It draws on existing examples in both educational research and
development studies that have discussed the use of ethnography and action research in specific projects. Interpretations of ethnography and action research
are developed that aim to minimise the epistemological differences between them.
The paper also contextualises an ‘ethnographic action research’ approach with reference to an example of the author’s research into participation in three ‘reception’ (first year of schooling) classes in the United Kingdom. It is argued that research into the theme of participation in early years education, using participative methods, was particularly suitable for this new methodological
approach
Effects of a Short-Term Shift to Low Temperature and of Long-Term Cold Hardening on Photosynthesis and Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase and Sucrose Phosphate Synthase Activity in Leaves of Winter Rye (Secale cereale L.)
Cold Hardening of Spring and Winter Wheat and Rape Results in Differential Effects on Growth, Carbon Metabolism, and Carbohydrate Content
Chlorophyll a/b-Binding Proteins, Pigment Conversions, and Early Light-Induced Proteins in a Chlorophyll b-less Barley Mutant
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