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Studies are presented in the context of the past attempts at finding nanocatalysts that can boost the performance of microbial fuel cells (MFCs) ─ in terms of waste treatment and energy generation. Given the great potential of biomimetically synthesized nanoparticles (BMNPs) in providing less expensive and more environmentally friendly alternatives to NPs synthesized by physical and chemical methods, as well as a near-total lack of previous work in this area, the current research was undertaken. Effect of gold and silver nanoparticles (NPs), synthesized biomimetically using five freely available weeds, was assessed as catalysts in the MFCs. In all cases, the nanoparticles were seen to enhance the coulombic efficiency (reflective of the reduction in the waste’s organic carbon load), maximum attainable power density, and overall energy yield of the MFCs by >200% relative to the uncatalyzed MFCs. Gold nanoparticles were more effective than silver nanoparticles by ≥ 20%. The results reveal that biomimetically synthesized NPs can be highly effective in reducing the operational costs as well as ecological footprints of MFCs and further work should be focused on NPs of non-precious metals.

Relative efficacy of five common weeds—of the kind that are either rooted in soil or which freely float over water—was assessed in rapid, effective and sustainable treatment of sewage at pilot plant scale in the recently developed and patented SHEFROL® bioreactors. The plants were utilized in a unit of capacity 12,000 liters/day (LPD) which, after two years of use, was enlarged to handle 40,000 LPD of sewage. It was then further expanded after an year to treat 57,000 LPD. All the five weeds, of which none has previously been tested in a pilot-scale SHEFROL, were able to foster highly efficient primary treatment (in terms of suspended and total solids) and secondary treatment (in terms of BOD and COD) to levels exceeding 85% in most cases. Additionally, the weeds also helped in achieving significant tertiary treatment. At different hydraulic retention times, and at steady state, the five weeds achieved treatment of BOD, COD, suspended solids, nitrogen, phosphorous, copper, nickel, zinc, and manganese in the ranges, 80–95, 79–91, 82–95, 61–71, 51–73, 37–43, 30–38, 39–47, and 27–35%, respectively. It all occurred in a single process step and without the use of any machine or chemical. This made the system not only simple and inexpensive to install but also to maintain. Over continuous long-term operation for four years, the system was seen to be very robust as it was able to handle wide variations in the volumes and characteristics of sewage, as well as absorb shock loads without compromising the reactor performance. The sustainability of the system can be further enhanced by upgrading it to a circular biorefinery. Energy sources in the form of volatile fatty acids (VFAs) can be extracted from the weeds removed from SHEFROL and then the weeds can be converted into organic fertilizer using high-rate vermireactors recently developed by the authors. A novel and inexpensive, yet very efficient sewage treatment system is presented. The versatility and robustness of the system has been assessed at pilot plant scale for several years. The long-term continuous studies establish the efficacy of five common weeds—not hitherto explored at pilot plant level—which can serve as the main bioagent(s) in the sewage treatment system. The system has the potential of being transformed in to a closed-loop-no-waste biorefinery [ABSTRACT FROM AUTHOR]

The efficacy of the well-known phytoremediation plant pistia (Pistia stratiotes), also called water lettuce or water cabbage, in treating sewage (greywater) was tested by its use as the main bioagent in the recently developed and patented 'sheet flow root level' (SHEFROL®) bioreactor. In contrast to previously reported systems, based on constructed wetland or stabilisation pond technologies, in which pistia needed wastewater hydraulic retention times (HRTs) of 24 h or more in enabling significant treatment of greywater, it achieved similar results in SHEFROL® several times more quickly, at the HRTs of only 4–6 h. Given that HRT directly influences reactor size, hence the system cost, the faster rate of treatment gives SHEFROL® a major economic advantage. In other ways, also, SHEFROL® appeared ideal for the use of pistia because of the reactor's ease of operation, robustness, very low requirement of energy or materials, and negligible ecological footprint. [ABSTRACT FROM AUTHOR]

Coping Strategy Scale (CSS) is widely used to measure how individuals cope with various kind of stressors related to infertility, therefore it is necessary to translate coping strategy scale in Urdu language to make it understandable by the Pakistani population. In the present study CSS developed by Schmidt is translated for assessment of coping strategies used by infertile females. 120 infertile females of age range 20-45 were selected to participate in the present study through purposive sampling technique. CSS was translated into Urdu language using the back translation method of Brislin. The alpha reliability coefficient for subscales of CSS Urdu version ranged from 0.62 to 0.83. The CSS Urdu version would be useful for the Pakistani population to find out coping strategies used by infertile females. In future CSS will be useful for researchers working with infertility and psychosocial issues. [ABSTRACT FROM AUTHOR]

Even as the world has been unsuccessfully trying to dispose off the rising quantities of its municipal solid waste (MSW) and hazardous waste (HW) in a clean manner, it has been confronted with an even more complex problem—of e-waste. Only a few countries in the developed world are able to scientifically recycle or dispose the e-waste they generate. In other developed countries only a fraction of the e-waste is properly recycled, the rest is either incinerated or sent to landfills—which are solutions that cause serious secondary problems. Worse still, a sizeable portion of the e-waste generated in the developed world is exported to developing countries where it is recycled or dumped without any concern for the gross pollution that is being caused. It can be said that if the situation vis-à-vis e-waste is posing a challenge in most developed counties, it is alarmingly bad in the developing world. In an attempt to contain the e-waste problem most of the developed world and several countries in the developing world have enacted legislation to curb illegal trafficking and unlicensed recycling of e-waste. These legislations invoke the extended producer responsibility concept based on life-cycle considerations in the hope that it will provide prevention as well as cure. Innumerable non-governmental organizations and citizen's groups have also been trying to help out. So far, all these measures together have achieved only a modicum of success—that, too, only in a few regions of the developed world—but if viewed on the global scale ever bigger streams of e-waste are threatening to join the rising tides of MSW and HW in engulfing the world. The present paper assesses the state-of-the-art, bringing out how and why the e-waste problem has been defying all attempts to contain it. The paper also brings out that—much the same way as has happened with MSW and HW—the size and the complexity of the e-waste problem is increasing at much faster rate than the efficacy of our strategies to contain it. This trend is not likely to reverse soon and the only viable means to solve the problem is to drastically reduce generation of waste. [ABSTRACT FROM PUBLISHER]

Relative efficacy of five common weeds-of the kind that are either rooted in soil or which freely float over water-was assessed in rapid, effective and sustainable treatment of sewage at pilot plant scale in the recently developed and patented SHEFROL ® bioreactors. The plants were utilized in a unit of capacity 12,000 liters/day (LPD) which, after two years of use, was enlarged to handle 40,000 LPD of sewage. It was then further expanded after an year to treat 57,000 LPD. All the five weeds, of which none has previously been tested in a pilot-scale SHEFROL, were able to foster highly efficient primary treatment (in terms of suspended and total solids) and secondary treatment (in terms of BOD and COD) to levels exceeding 85% in most cases. Additionally, the weeds also helped in achieving significant tertiary treatment. At different hydraulic retention times, and at steady state, the five weeds achieved treatment of BOD, COD, suspended solids, nitrogen, phosphorous, copper, nickel, zinc, and manganese in the ranges, 80-95, 79-91, 82-95, 61-71, 51-73, 37-43, 30-38, 39-47, and 27-35%, respectively. It all occurred in a single process step and without the use of any machine or chemical. This made the system not only simple and inexpensive to install but also to maintain. Over continuous long-term operation for four years, the system was seen to be very robust as it was able to handle wide variations in the volumes and characteristics of sewage, as well as absorb shock loads without compromising the reactor performance. The sustainability of the system can be further enhanced by upgrading it to a circular biorefinery. Energy sources in the form of volatile fatty acids (VFAs) can be extracted from the weeds removed from SHEFROL and then the weeds can be converted into organic fertilizer using high-rate vermireactors recently developed by the authors.