Promoting international cultural and academic collaborative communication through technologies of open course ware

In the diverse cultures of an increasingly transnational world where\ud academic literacy in English or Englishes is required for advancement in\ud universities, communication technologies play critical roles. This paper integrates\ud scholars from diverse cultures through online technology which allows for\ud participants from several universities to develop their awareness of diverse\ud cultures and academic English across disciplines. This research addresses the issue\ud of how online collaboration among scholars can develop their technological,\ud cultural and academic literacies which are essential to their academic progress. By\ud creating electronic discussion forums that include scholars from universities\ud worldwide it is possible to engage in transcultural dialogue regarding how diverse\ud cultures view technology as a means to advance academic and cultural literacy.\ud Through combining the wealth of academic Open Course Ware (OCW) through\ud the consortium and linkages with international universities it is possible to create\ud credit courses for students in each of their home universities thereby overcoming\ud the major limitation of OCW by providing access to credit for OCW courses

The synthesis and medicinal applications of pyrogallol4arenes

To date almost all pyrogallol[4]arenes reported in the literature have been prepared from alkyl aldehydes. We were interested in preparing more pyrogallol[4]arenes from commercially available benzaldehydes. On synthesising these compounds we discovered that they are structurally unique, compared to previously reported pyrogallol[4]arenes, as they exist in a rctt chair conformation as determined by X-ray crystallography and 1HNMR. We also discovered from our synthetic studies that the yields for the pyrogallol[4]arenes depend strongly on the electron donating/withdrawing ability of substituents placed in the benzaldehyde, the more electron withdrawing the higher the yield. We also discovered a unique metal salt effect on the condensation of pyrogallol with 4-fluorobenzaldehyde that doubled the yields o f the resulting macrocycle. Interestingly, this effect is absent with the condensation of pyrogallol with alkyl aldehydes. The role of steric effects, using bulky substituted benzaldehydes was also investigated to determine whether the stereochemical outcome for these condensation reactions could be controlled. The further derivatisation of the pyrogallol[4]arenes was also investigated. The preparation of partially and completely alkylated derivatives of these macrocycles was of interest to us. We found that the introduction of acetate groups could be readily accomplished, however other alkyl groups could not be efficiently introduced into the pyrogallol[4]arenes. The partially and completely alkylated acetate derivatives of pyrogallol[4]arene were screened for biological activity against HIV-1. It was discovered that the partially alkylated derivatives possessed higher selectivity indexes than the completely alkylated derivatives indicating that biological activity may not be dependent on charge

Sustainable Portfolios to Maximize Alpha

There has been a new movement for investment funds to align with investor morals. They are known as Environmental, Social, and Governance (ESG) funds, and have become a strong focus for asset management firms. Currently these funds have a negative stigma because most investors believe that due to added constraints on these portfolios, they will not be able to outperform non-sustainable portfolios. This is why the sustainable investment portfolios will be created. The portfolios undergo two focuses. The first portfolio employs a negative screening, which means that the portfolio will exclude specific industries that are deemed unsustainable. The other portfolio undergoes a positive screening. This means that there are specific parameters that focus on green initiatives. The purpose of these sustainable portfolios is to show investors that they can have strong returns compared to their benchmarks and still align with their values

Fluid flow and heat transfer in a dual-wet micro heat pipe

Micro heat pipes have been used to cool micro electronic devices, but their heat transfer coefficients are low compared with those of conventional heat pipes. In this work, a dual-wet pipe is proposed as a model to study heat transfer in micro heat pipes. The dual-wet pipe has a long and narrow cavity of rectangular cross-section. The bottom-half of the horizontal pipe is made of a wetting material, and the top-half of a non-wetting material. A wetting liquid fills the bottom half of the cavity, while its vapour fills the rest. This configuration ensures that the liquid–vapour interface is pinned at the contact line. As one end of the pipe is heated, the liquid evaporates and increases the vapour pressure. The higher pressure drives the vapour to the cold end where the vapour condenses and releases the latent heat. The condensate moves along the bottom half of the pipe back to the hot end to complete the cycle. We solve the steady-flow problem assuming a small imposed temperature difference between the two ends of the pipe. This leads to skew-symmetric fluid flow and temperature distribution along the pipe so that we only need to focus on the evaporative half of the pipe. Since the pipe is slender, the axial flow gradients are much smaller than the cross-stream gradients. Thus, we can treat the evaporative flow in a cross-sectional plane as two-dimensional. This evaporative motion is governed by two dimensionless parameters: an evaporation number E defined as the ratio of the evaporative heat flux at the interface to the conductive heat flux in the liquid, and a Marangoni number M. The motion is solved in the limit E→∞ and M→∞. It is found that evaporation occurs mainly near the contact line in a small region of size E−1W, where W is the half-width of the pipe. The non-dimensional evaporation rate Q* ~ E−1 ln E as determined by matched asymptotic expansions. We use this result to derive analytical solutions for the temperature distribution Tp and vapour and liquid flows along the pipe. The solutions depend on three dimensionless parameters: the heat-pipe number H, which is the ratio of heat transfer by vapour flow to that by conduction in the pipe wall and liquid, the ratio R of viscous resistance of vapour flow to interfacial evaporation resistance, and the aspect ratio S. If HRxs226B1, a thermal boundary layer appears near the pipe end, the width of which scales as (HR)−1/2L, where L is the half-length of the pipe. A similar boundary layer exists at the cold end. Outside the boundary layers, Tp varies linearly with a gradual slope. Thus, these regions correspond to the evaporative, adiabatic and condensing regions commonly observed in conventional heat pipes. This is the first time that the distinct regions have been captured by a single solution, without prior assumptions of their existence. If HR ~ 1 or less, then Tp is linear almost everywhere. This is the case found in most micro-heat-pipe experiments. Our analysis of the dual-wet pipe provides an explanation for the comparatively low effective thermal conductivity in micro heat pipes, and points to ways of improving their heat transfer capabilities

Meta-analysis reveals ammonia-oxidizing bacteria respond more strongly to nitrogen addition than ammonia-oxidizing archaea

Shifts in microbial communities driven by anthropogenic nitrogen (N) addition have broad-scale ecological consequences. However, responses of microbial groups to exogenous N supply vary considerably across studies, hindering efforts to predict community changes. We used meta-analytical techniques to explore how amoA gene abundances of ammonia-oxidizing archaea (AOA) and bacteria (AOB) respond to N addition, and found that N addition increased AOA and AOB abundances by an average of 27% and 326%, respectively. Responses of AOB varied by study type, ecosystem, fertilizer type, and soil pH, and were strongest in unmanaged wildland soils and soils fertilized with inorganic N sources. Increases in nitrification potential with N addition significantly correlated with only AOB. Our analyses suggest that elevated N supply enhances soil nitrification potential by increasing AOB populations, and that this effect may be most pronounced in unmanaged wildland soils

Ecosystem modelling of tropical wetlands

4.1 Background Modelling is essential for enhancing our understanding of the functioning of tropical wetland ecosystems, and for simulating future trajectories and testing for system thresholds. Anthropogenic activities such as drainage and land-use change can be integrated in models and their impacts on fluxes of greenhouse gas concentrations simulated. Models can also be used to test the response of peatlands and mangroves to climate extremes, variability and change, and to estimate reference levels and greenhouse gas emissions scenarios in the framework of climate change mitigation projects such as REDD+. In coastal settings, models are used to explore wetland resilience to sea-level rise. Finally, models can also be developed to support the decision making process by providing policyrelevant information on the consequences and trade-offs of adopting different management and climate scenarios