scholarly journals Copper-zeolite integrated stormwater biofilter for nutrient removal – the impact of intermittent wetting and drying conditions

2020 ◽  
Vol 2 (1) ◽  
pp. 352-363
Author(s):  
Yali Li ◽  
Ana Deletic ◽  
David T. McCarthy

Abstract A large-scale column study was conducted to examine the sediment and nutrient removal performance of stormwater biofilters that contained layers of novel copper-zeolite filter media. The filters were exposed to stormwater under varied dosing frequency over 33 weeks and were assessed for their hydraulic performance and their efficiency in removing sediment and nutrients. The non-vegetated sand filters with layers of copper-zeolite media (SCu filters) achieved consistently good removal of total phosphorus (87%) despite the challenging dry-wet cycles, and the effluent concentration met a long-term irrigation guideline (0.05 mg/L). The same design achieved 51% removal of total nitrogen above the Australian runoff quality load reduction targets (45%). Incorporation of Leptospermum continentale into the copper-zeolite filters (LCCu-T) maintained the phosphorus removal (86%) and led to a slight increase in total nitrogen removal (57%). Both designs maintained good water permeability (200 mm/h at the end of the last wet period). Copper-zeolite played a mixed role in the system: enhancing nutrients removal through precipitation and ion exchange, maintaining high water permeability, limiting the advantages of vegetation on nutrient removal. Future studies should refine biofilter design and vegetation selection to augment the performance of copper-zeolite filters by integrating the advantages of vegetation on nutrient removal.

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Yam Nath Paudel ◽  
Efthalia Angelopoulou ◽  
Bhupendra Raj Giri ◽  
Christina Piperi ◽  
Iekhsan Othman ◽  
...  

: COVID-19 has emerged as a devastating pandemic of the century that the current generations have ever experienced. The COVID-19 pandemic has infected more than 12 million people around the globe and 0.5 million people have succumbed to death. Due to the lack of effective vaccines against the COVID-19, several nations throughout the globe has imposed a lock-down as a preventive measure to lower the spread of COVID-19 infection. As a result of lock-down most of the universities and research institutes has witnessed a long pause in basic science research ever. Much has been talked about the long-term impact of COVID-19 in economy, tourism, public health, small and large-scale business of several kind. However, the long-term implication of these research lab shutdown and its impact in the basic science research has not been much focused. Herein, we provide a perspective that portrays a common problem of all the basic science researchers throughout the globe and its long-term consequences.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
D Panatto ◽  
P Landa ◽  
D Amicizia ◽  
P L Lai ◽  
E Lecini ◽  
...  

Abstract Background Invasive disease due to Neisseria meningitidis (Nm) is a serious public health problem even in developed countries, owing to its high lethality rate (8-15%) and the invalidating sequelae suffered by many (up to 60%) survivors. As the microorganism is transmitted via the airborne route, the only available weapon in the fight against Nm invasive disease is vaccination. Our aim was to carry out an HTA to evaluate the costs and benefits of anti-meningococcal B (MenB) vaccination with Trumenba® in adolescents in Italy, while also considering the impact of this new vaccination strategy on organizational and ethics aspects. Methods A lifetime Markov model was developed. MenB vaccination with the two-dose schedule of Trumenba® in adolescents was compared with 'non-vaccination'. Two perspectives were considered: the National Health Service (NHS) and society. Three disease phases were defined: acute, post-acute and long-term. Epidemiological, economic and health utilities data were taken from Italian and international literature. The analysis was conducted by means of Microsoft Excel 2010®. Results Our study indicated that vaccinating adolescents (11th year of life) with Trumenba® was cost-effective with an ICER = € 7,912/QALY from the NHS perspective and € 7,758/QALY from the perspective of society. Vaccinating adolescents reduces the number of cases of disease due to meningococcus B in one of the periods of highest incidence of the disease, resulting in significant economic and health savings. Conclusions This is the first study to evaluate the overall impact of free MenB vaccination in adolescents both in Italy and in the international setting. Although cases of invasive disease due to meningococcus B are few, if the overall impact of the disease is adequately considered, it becomes clear that including anti-meningococcal B vaccination into the immunization program for adolescents is strongly recommended from the health and economic standpoints. Key messages Free, large-scale MenB vaccination is key to strengthening the global fight against invasive meningococcal disease. Anti-meningococcal B vaccination in adolescents is a cost-effective health opportunity.


2021 ◽  
Author(s):  
Taha Sezer ◽  
Abubakar Kawuwa Sani ◽  
Rao Martand Singh ◽  
David P. Boon

<p>Groundwater heat pumps (GWHP) are an environmentally friendly and highly efficient low carbon heating technology that can benefit from low-temperature groundwater sources lying in the shallow depths to provide heating and cooling to buildings. However, the utilisation of groundwater for heating and cooling, especially in large scale (district level), can create a thermal plume around injection wells. If a plume reaches the production well this may result in a decrease in the system performance or even failure in the long-term operation. This research aims to investigate the impact of GWHP usage in district-level heating by using a numerical approach and considering a GWHP system being constructed in Colchester, UK as a case study, which will be the largest GWHP system in the UK. Transient 3D simulations have been performed pre-construction to investigate the long-term effect of injecting water at 5°C, into a chalk bedrock aquifer. Modelling suggests a thermal plume develops but does not reach the production wells after 10 years of operation. The model result can be attributed to the low hydraulic gradient, assumed lack of interconnecting fractures, and large (>500m) spacing between the production and injection wells. Model validation may be possible after a period operational monitoring.</p>


2011 ◽  
Vol 94-96 ◽  
pp. 810-814
Author(s):  
Jin Shan Zhang ◽  
Wei Sheng Zhang ◽  
Chen Cheng ◽  
Lin Yun Sun

Bohai Bay is an semi-closed bay, the storm surge disaster is very serious in past. Now more and more large ocean engineering are built here, To study changes of storm surge induced by the construction of large-scale coastal engineering in Bohai Bay in present, 2D numerical storm surge model is established with large - medium - small model nested approach. The three most typical storms surges: 9216, 9711 and by cold wave in October 2003 are simulated in the condition of before and after implementation of planning projects in Bohai Bay. Changes of storm surge water level due to implementation of artificial projects are analysis in this paper.


Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Peng Huang ◽  
Jixiong Zhang ◽  
Qi Zhang ◽  
Ntigurirwa Jean Damascene ◽  
Yuming Guo

With the gradual increase in mining depth of coal resource exploitation, deep backfilling mining has effectively solved the impact of strong deep mine pressure and strong mining disturbances. However, after deep backfilling mining, the backfilling material is subjected to high stress for a long time, and its viscoelasticity has a significant impact on the roof control effect. This paper uses a large-scale bulk confinement test device to analyze the viscoelastic properties of gangue, establishes a high-precision fractional viscoelastic creep model, and identifies the gangue parameters. The established fractional viscoelastic model was used as the foundation model of the beam, and the roof model based on the fractional viscoelastic foundation was solved. The top deformation characteristics of elastic foundation and fractional foundation were compared and analyzed, and the time effect, viscoelastic effect, and order effect of the fractional order viscoelastic foundation beam were discussed. The results show that the viscosity of gangue increased under the action of deep high stress. As time increased, the roof deformation also increased. In order to more effectively control the long-term deformation of the roof, the viscosity coefficient of the backfilling material should be greater than 20 MPa. This research provides relevant guidance for the requirements of backfilling materials for deep backfilling mining and the prediction of long-term dynamic deformation of the roof in underground excavations.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4775-4775
Author(s):  
Katharina Schallmoser ◽  
Christina Bartmann ◽  
Eva Rohde ◽  
Simone Bork ◽  
Christian Guelly ◽  
...  

Abstract Abstract 4775 Background: Based on promising experimental studies with mesenchymal stem and progenitor cells (MSPCs) multiple clinical trials have been initiated. In previous studies we have observed genomic stability of MSPCs after efficient short-term expansion in a humanized GMP compliant system with pooled human platelet lysate (pHPL) replacing fetal bovine serum (FBS) as the cell culture supplement (Schallmoser K. and Strunk D., Journal of Visualized Experiments (32) DOI: 10.3791/1523, 2009). Notably, depending on culture protocols, an extensive propagation with highly variable cell culture duration may be necessary to yield enough MSPCs for therapy. The decline in proliferation rates of MSPCs in the course of the different long-term expansion procedures may indicate a propensity for replicative senescence which may hamper long term functionality in vivo. We have therefore initiated a molecular profiling of senescence-associated regulated genes to determine the state of senescence before MSPC transplantation. Methods: Human bone marrow-derived MSPCs were cultured following a highly efficient two-passage protocol (primary culture of unseparated bone marrow and subsequent large scale expansion; Schallmoser K. et al., Tissue Engineering 14:185-196, 2008) compared to conventional serial passaging in three different growth conditions with regularly more then four passages to obtain comparable final cell numbers. Culture media were either supplemented with FBS in different concentrations or pHPL. Gene expression changes were tested by microarray analysis and selected targets were reanalyzed by quantitative real-time PCR. The genomic stability of MSPCs after long-term culture was determined by array comparative genomic hybridization (CGH). Results: Despite high proliferation rate large scale expanded MSPCs showed genomic stability in array CGH. Long-term MSPC growth induced similar gene expression changes in MSPCs irrespective of isolation and expansion conditions. In particular, genes involved in cell differentiation, apoptosis and cell death were up-regulated, whereas genes involved in mitosis and proliferation were down-regulated. Furthermore, overlapping senescence-associated gene expression changes were found in all MSPC preparations. The genomic copy number variations detected in MSPCs of early and late passages in all culture conditions did not coincide with differentially expressed genes. Conclusion: Our data indicate that MSPC expansion can induce gene expression changes independent of isolation and FBS-supplemented as well as FBS-free expansion conditions. A panel of genes will be presented that might offer a practicable approach to assess MSPC quality with regard to the state of replicative senescence in advance of therapeutic application. Determining the impact of senescence acquired during cell expansion on the therapeutic potential of MSCPs for both immune modulation and organ regeneration may help to develop more efficient treatment strategies. Disclosures: No relevant conflicts of interest to declare.


Author(s):  
Nguyen Van Tan

This paper examines the impact of equitization on financial and operating performance of state-owned enterprises (SOEs) in Vietnam. Previous related privatization theories have not explained whether there is an improvement in financial and operating performance of equitized SOEs compared to non-equitized SOEs or not. This study proposes to use with-without comparison method through the average treatment effect measuring the impact of equitization on financial and operating performance of SOEs. By using data of 114 SOEs equitized in the period from 2012 to 2014, the author finds that equitized SOEs can not improve profitability, operating efficiency, and output when considering non-equitized SOEs. There is also no evidence for a reduction in the number of employees of equitized SOEs after equitization. These findings are in contrast to previous studies in Vietnam, but there are similarities with the results of studies in China. This is because equitized SOEs in the early post-equitization period in Vietnam are still monitored by the Vietnamese government, as well as the equitized enterprises in the period 2012-2014 are mainly large-scale ones with slow change of operating objectives, monitoring mechanism and weak competitiveness after equitization. However, equitization can help equitized SOEs operate more efficiently than non–equitized SOEs when considering non-listing status or industry group. This research provides implications for the Vietnamese government to encourage non-equitized enterprises to participate in the equitization program actively. The research results also help investors to have appropriate long-term investment strategies in equitized SOEs. This paper also has some limitations for further research.


2021 ◽  
Author(s):  
Marina Martinez-Garcia ◽  
Alejandro Rabasa ◽  
Xavier Barber ◽  
Kristina Polotskaya ◽  
Kristof Roomp ◽  
...  

Population confinements have been one of the most widely adopted non-pharmaceutical interventions (NPIs) implemented by governments across the globe to help contain the spread of the SARS-CoV-2 virus. While confinement measures have been proven to be effective to reduce the number of infections, they entail significant economic and social costs. Thus, different policy makers and social groups have exhibited varying levels of acceptance of this type of measures. In this context, understanding the factors that determine the willingness of individuals to be confined during a pandemic is of paramount importance, particularly, to policy and decision-makers. In this paper, we study the factors that influence the unwillingness to be confined during the COVID-19 pandemic by means of a large-scale, online population survey deployed in Spain. We apply both quantitative (logistic regression) and qualitative (automatic pattern discovery) methods and consider socio-demographic, economic and psychological factors, together with the 14-day cumulative incidence per 100,000 inhabitants. Our analysis of 109,515 answers to the survey covers data spanning over a 5-month time period to shed light on the impact of the passage of time. We find evidence of pandemic fatigue as the percentage of those who report an unwillingness to be in confinement increases over time; we identify significant gender differences, with women being generally less likely than men to be able to sustain long-term confinement of at least 6 months; we uncover that the psychological impact was the most important factor to determine the willingness to be in confinement at the beginning of the pandemic, to be replaced by the economic impact as the most important variable towards the end of our period of study. Our results highlight the need to design gender and age specific public policies, to implement psychological and economic support programs and to address the evident pandemic fatigue as the success of potential future confinements will depend on the population's willingness to comply with them.


2021 ◽  
Vol 15 (1) ◽  
pp. e0008926
Author(s):  
Raphael Awah Abong ◽  
Glory Ngongeh Amambo ◽  
Ali Ahamat Hamid ◽  
Belinda Agbor Enow ◽  
Amuam Andrew Beng ◽  
...  

Background The impact of large scale Mass Drug Adminstration (MDA) of ivermectin on active onchocerciasis transmission by Simulium damnosum, which transmits the parasite O. volvulus is of great importance for onchocerciasis control programmes. We investigated in the Mbam river system area, the impact of MDA of ivermectin on entomological indices and also verify if there are river system factors that could have favoured the transmission of onchocerciasis in this area and contribute to the persistence of disease. We compared three independent techniques to detect Onchocerca larvae in blackflies and also analyzed the river system within 9 months post-MDA of ivermectin. Method Simulium flies were captured before and after 1, 3, 6 and 9months of ivermectin-MDA. The biting rate was determined and 41% of the flies dissected while the rest were grouped into pools of 100 flies for DNA extraction. The extracted DNA was then subjected to O-150 LAMP and real-time PCR for the detection of infection by Onchocerca species using pool screening. The river system was analysed and the water discharge compared between rainy and dry seasons. Principal findings We used human landing collection method (previously called human bait) to collect 22,274 adult female Simulium flies from Mbam River System. Of this number, 9,134 were dissected while 129 pools constituted for molecular screening. Overall biting and parous rates of 1113 flies/man/day and 24.7%, respectively, were observed. All diagnostic techniques detected similar rates of O. volvulus infection (P = 0.9252) and infectivity (P = 0.4825) at all monitoring time points. Onchocerca ochengi larvae were only detected in 2 of the 129 pools. Analysis of the river drainage revealed two hydroelectric dams constructed on the tributaries of the Mbam river were the key contributing factor to the high-water discharge during both rainy and dry seasons. Conclusion Results from fly dissection (Microscopy), real-time PCR and LAMP revealed the same trends pre- and post-MDA. The infection rate with animal Onchocerca sp was exceptionally low. The dense river system generate important breeding sites that govern the abundance of Simulium during both dry and rainy seasons.


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