Boron Removal By Reverse Osmosis Membranes

Ph.DDOCTOR OF PHILOSOPH

Political transition and emergent forest-conservation issues in Myanmar.

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions

Political transition and emergent forest-conservation issues in Myanmar.

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions

Time to anti-retroviral therapy among people living with HIV enrolled into care in Myanmar: how prepared are we for ‘test and treat’?

Background: Among people living with HIV (PLHIV) enrolled into care, time to anti-retroviral therapy (ART) has not been studied in Myanmar. To inform progress, we conducted this operational research among treatment-naive PLHIV (≥18 years) enrolled during a period of three years (2014–2016) at Pyin Oo Lwin, Myanmar. Objectives: To determine (i) the time from HIV diagnosis to ART initiation (time to ART) and associated factors and (ii) the association between time to ART and attrition (loss to follow-up and death) from ART care. Methods: This was a retrospective cohort study involving a record review of secondary programme data. The PLHIV were followed up to 5 December 2017 for ART initiation and up to 31 March 2018 (date of censoring) for attrition during ART. Results: Of 543 enrolled, 373 (69%) were found to be eligible and initiated on ART. Of 373, 245 (67%) were initiated within 6 weeks of enrolment. The median enrolment delay (from diagnosis) was 4 (IQR: 1, 14) days and median ART initiation delay (from ART eligibility) was 20 (IQR: 13, 36) days. The median time to ART (excluding the time interval in pre-ART care) was 29 (IQR: 18, 55) days and was significantly long in those with prevalent TB and CD4 count ≥ 500/mm3 at enrolment. Among 373, the annual incidence density of attrition was 12.8% (0.95 CI: 10.2, 15.7). Attrition was common in first 100 days. Time to ART (after excluding time interval in pre-ART care) was not significantly associated with attrition. Conclusion: The programme appears to be on track to initiate ART as soon as possible in a ‘test and treat’ scenario (implemented since September 2017) subject to interventions to reduce ART initiation delay

Experimental studies and modeling on concentration polarization in forward osmosis

Concentration polarization (CP) is an important issue in forward osmosis (FO) processes and it is believed that the coupled effect of dilutive internal CP (DICP) and concentrative external CP (CECP) limits FO flux. The objective of this study was to distinguish individual contribution of different types of DICP and CECP via modeling and to validate it by pilot studies. The influence of DICP/CECP on FO flux has been investigated in this study. The CP model presented in this work was derived from a previous study and evaluated by bench-scale FO experiments. Experiments were conducted with drinking water as the feed and NaCl/MgSO(4) as draw solutions at different concentrations and velocities. Modeling results indicated that DICP contributed to a flux reduction by 99.9% for 0.5 M NaCl as a draw solution although the flow pattern of both feed and draw solutions was turbulent. DICP could be improved via selection of the draw solution. The modeling results were well fit with the experimental data. It was concluded that the model could be used for selection of the draw solution and prediction of water flux under similar situation. A draw solution with greater diffusion coefficient or a thinner substrate of an asymmetric FO membrane resulted in a higher flux

Experimental studies and modeling on concentration polarization in forward osmosis

Concentration polarization (CP) is an important issue in forward osmosis (FO) processes and it is believed that the coupled effect of dilutive internal CP (DICP) and concentrative external CP (CECP) limits FO flux. The objective of this study was to distinguish individual contribution of different types of DICP and CECP via modeling and to validate it by pilot studies. The influence of DICP/CECP on FO flux has been investigated in this study. The CP model presented in this work was derived from a previous study and evaluated by bench-scale FO experiments. Experiments were conducted with drinking water as the feed and NaCl/MgSO(4) as draw solutions at different concentrations and velocities. Modeling results indicated that DICP contributed to a flux reduction by 99.9% for 0.5 M NaCl as a draw solution although the flow pattern of both feed and draw solutions was turbulent. DICP could be improved via selection of the draw solution. The modeling results were well fit with the experimental data. It was concluded that the model could be used for selection of the draw solution and prediction of water flux under similar situation. A draw solution with greater diffusion coefficient or a thinner substrate of an asymmetric FO membrane resulted in a higher flux

Optimization of operating conditions in forward osmosis for osmotic membrane bioreactor

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