Resource Use and Water Implications of Material Consumption in Consumer Electronics

Rapid technological innovation has introduced a broad spectrum of materials in the consumer electronics sector. Consumption of these materials increases the demand for water and potentially discharge contaminants into the water resources across their life cycle, exacerbating freshwater scarcity and pollution. These water impacts have not yet been fully studied, as most literature on consumer electronics focuses on supply chain energy, carbon footprint, or end of life management. Evaluating water impacts requires data on material content, life cycle water consumption and emissions at spatial level, and availability of impact assessment models that connects life cycle data to water impacts. Data on these aspects are available at varied degrees for different materials used in the electronics. This research created data on materials used in consumer electronics and studied implications on water resources for two major material categories - metals and plastics. Bill of materials (BOMs) data were created for 95 unique consumer electronic products that contain information on mass of major materials and components. Then, life cycle water impacts associated with extraction and production of metals found in consumer electronics are evaluated to identify material hotspots for future improvement. Water impacts were analyzed for individual metals and then for the representative metal profile of case study products (smartphones and laptop computers). Finally, profile of polymers and additives in the e-waste is created to understand linkage to water impacts as well to evaluate implications to establishing e-plastics circular systems. Results indicate that, on the individual material level, precious metals have the highest water impacts in their supply chain. Water scarcity impact is mainly because of water consumed directly for mining operations and indirectly for energy production, and water degradation attributed to metal emissions during mine tailings management. The geographical region where metal production happens is also a contributing factor to water impacts, as water stress varies spatially. Therefore, sourcing metals from regions with lower water stress is an opportunity to reduce supply chain water impacts. At product level, precious metals have the highest contribution per smartphone, whereas aluminum has the highest contribution per laptop. Product design changes, such as use of recycled metal or using a low impact metal are observed to reduce water impacts. Further, e-waste shows a diverse mix of polymers and additives, including flame retardants, pigments, and heavy metals that can potentially pollute water resources if released. As a result, transition to circular systems is important to keep the plastics from entering the environment. To enable this transition, multistakeholder engagement in the electronics sector is required to make an informed decisions in product design, policy planning and material recovery infrastructure

Basin Scale Performance of a Distributed Rainfall-Runoff Model Using Uncertainty Modelling Approach in Data Scarce Region

Lack of hydrological information of the most basins in Tanzania increase uncertainties in understanding hydrological processes in the basin, and consequently leads to risks decision making related to significant water resources development plans and climate change adaptation. The lack of hydrological information also is coupled with uncertainty related to the predictions of future climate and land use change. Some of the gaps can be filled using rainfall-runoff modeling, which results can be used to generate reliable information to enable decision making and planning for water resources management. This paper discusses the results of applying a semi-distributed rainfall-runoff model which was established for the Little Ruaha Sub-Basin, using the available historical data, with a goal of understanding processes of runoff generation and the inherent uncertainty related to data. Issues of water resources assessment in the basin and approaches used to address them, and some directions for future research are discussed. There are challenges associated with the quality of data for model set-up and understanding of the model structure. Despite these challenges, there remain many opportunities to improve the methods used for water resources assessment and management within the basin

Anti-allergic activity of some selected plants in the genus Boesenbergia and Kaempferia

Ethanolic and water extracts from the rhizomes of eight selected Zingiberaceous plants, including Boesenbergiathorelii, Boesenbergia sp 1, Boesenbergia sp 2, Boesenbergia sp 3, Kaempferia angustifolia, Kaempferia marginata,Kaempferia rotunda and Kaempferia sp were tested for their anti-allergic activities using the rat basophilic leukemia strain2H3 (RBL-2H3) cell line. Both the ethanolic (EtOH) and water extracts of Boesenbergia thorelii exhibited the most potentanti-allergic effects against antigen-induced â-hexosaminidase release as a marker of degranulation in RBL-2H3 cells, withIC50 values of 23.0 and 26.3 g/ml, respectively. Other extracts also had some activity from Boesenbergia sp 2 (EtOH, IC50 =38.3 g/ml), Kaempferia marginata (water, IC50 = 38.4 g/ml), Boesenbergia sp 3 (EtOH, IC50 = 49.4 g/ml) and Kaempferiaangustifolia (water, IC50 = 55.6 g/ml), whereas other Boesenbergia and Kaempferia spp had little or no activity. These findingssupport the use of Boesenbergia thorelii for the treatment of allergies and allergy-related diseases

SCREENING OF ANTIOXIDANT ACTIVITY AND TOTAL PHENOLIC CONTENT IN RAPHANUS SATIVUS POD

Objective: The aim of this study was to evaluate the antioxidant activity and total phenolic content of Raphanus sativus L. Var. caudatus Alef pod extracts. Methods: In this study, the extract of R. sativus pod was prepared in three different types of solvent. The antioxidant activitiy of R. sativus extract was determined using a spectrophotometric technique, based on a free radical diphenyl-picryhydrazyl scavenging assay (DPPH assay) and a ferric reducing antioxidant power assay (FRAP assay). Total phenolic content was also observed using the spectrophotometric technique. Results: The result showed that the antioxidant activity which was expressed by IC50 values varied from 1,365 to 4,371 mg/ml and 312 to 6,478 mg/ml, based on DPPH assay and FRAP assay, respectively. Total phenolic content was also evaluated and calculated as gallic acid equivalents which ranged from 0.26 to 34.60 mg gallic acid per 100 g fresh sample. Conclusion: It was suggested that hexane extract of R. sativus pod contained the highest amount of phenolic compounds in comparison with those of dichloromethane part and ethanol part. The result from FRAP assay was positively correlated to total phenolic content which the highest antioxidant value belongs to the hexane extract of R. sativus pod. It was concluded that R. sativus pod contained phenolic compounds which showed mild antioxidant activity

Delay-efficient 4:3 counter design using two-bit reordering circuit for high-speed Wallace tree multiplier

In many signal processing applications, multiplier is an important functional block that plays a crucial role in computation. It is always a challenging task to design the delay optimized multiplier at the system level. A new and delay-efficient structure for the 4:3 counter is proposed by making use of a two-bit reordering circuit. The proposed 4:3 counter along with the 7:3 counter, full adder (FA), and half adder (HA) circuits are employed in the design of delay-efficient 8-bit and 16-bit Wallace tree multipliers (WTMs). Using Xilinx Vivado 2017.2, the designed circuits are simulated and synthesized by targeting the device ‘xc7s50fgga484-1’ of Spartan 7 family. Further, in terms of lookup table (LUT) count, critical path delay (CPD), total on-chip power, and power-delay-product (PDP), the performance of the proposed multiplier circuit is compared with the existing multipliers

THE STUDY OF ANTI-INFLAMMATORY AND ANTIOXIDANT ACTIVITY IN COLD PRESS RICE BRAN OIL FROM RICE IN THAILAND

Objective: The present study is investigation in the rice bran oil from four rice varieties in term of anti-inflammatory and antioxidant activities. Methods: This research studied the effects of anti-inflammatory and antioxidant activity from cold press rice bran oil. For anti-inflammatory, their inhibitory activity of nitric oxide (NO) production using RAW267.4 cell lines was evaluated. And two methods for antioxidant activities, DPPH radical scavenging assay (DPPH assay) and Ferric Reducing Antioxidant Power (FRAP) assay were used and compared with gallic acid standard and ferric sulfate (FeSO4), respectively. Results: For the Oryza Sativa L. Khaw-khaw exhibited the highest activity against the NO production with an IC50 value of 41.96 μg/ml, followed by O. Sativa L. Hom Pathum (46.58 μg/ml), O. Sativa L. Hom Mali (53.84 μg/ml) and O. Sativa L. Hom Mali Gorkho (59.43 μg/ml). However, the antioxidant activity, DPPH method found O. Sativa L. Hom Mali Gorkho displayed the most potent effect with IC50 value of 0.08 mg/ml, followed by O. Sativa L. Hom Pathum (0.11mg/ml), O. Sativa L. Hom Mali (0.12mg/ml) and O. Sativa L. Khaw khaw (0.88 mg/ml), respectively. The assay of FRAP showed the highest in O. Sativa L. Hom Mali Gorkho with an IC50 value 2.27 mg/ml, followed by O. Sativa L. Hom Pathum (4.30 mg/ml), O. Sativa L. Khaw khaw (6.67 mg/ml) and O. Sativa L. Hom Mali (7.68 mg/ml), respectively. Conclusion: This study indicated that cold press rice bran oil from rice varieties in Thailand is responsible for anti-inflammatory and antioxidant activity. Therefore, this study supports the tradition use of cold press rice bran oil for treatment of inflammatory related diseases though the inhibition of nitric oxide release

TOTAL PHENOLIC AND FLAVONOID CONTENTS AND ANTIOXIDANT PROPERTIES OF THAI TRADITIONAL HERBAL

Objective: The study investigated for the several of solvent on merits Trigasornmas formula in term of phenolic, flavonoid contents and antioxidant activities.Methods: This research studied the effects of extraction solvents in water, ethyl acetate, methanol, dichloromethane, ethanol and hexane extracts of Trigasormmas formula. Total phenolic and total flavonoid content were evaluated according to the Folin- Ciocalteu procedure and a aluminium chloride colorimetric method, respectively. Two methods of antioxidant activities were used DPPH radical scavenging assay (DPPH assay) and Ferric Reducing Antioxidant Power (FRAP) assay. According to our study, the outcomes of free radical scavenging properties were demonstrated in terms of mg gallic acid equivalent (GAE)/100 g sample and mg ferric sulfate equivalent (FeSO4)/100 g sample antioxidant, respectively.Results: The average total phenolic content of water extract was 1,955.23±60.87 mg GAE/100 g sample which was higher than the other solvents while the methanol extract showed the highest flavonoid content at about 321.15±9.12 mg FeSO4/100g sample. For antioxidant properties, DPPH and FRAP assay, the highest values were found in water extract at about 158.93±12.45 mg GAE/100g sample and 2,118.87±24.38 mg FeSO4/100g sample, respectively.Conclusion: The obtained results support the use of this Thai traditional herbal formula, and suggest more investigation.Â

Uncertainties in modelling hydrological responses in gauged and ungauged sub‐basins

The world is undergoing rapid changes and the future is uncertain. The changes are related to modification of the landscape due to human activities, such as large and small scale irrigation, afforestation and changes to the climate system. Understanding and predicting hydrologic change is one of the challenges facing hydrologists today. Part of this understanding can be developed from observed data, however, there often too few observations and those that are available are frequently affected by uncertainties. Hydrological models have become essential tools for understanding historical variations of catchment hydrology and for predicting future possible trends. However, most developing countries are faced with poor spatial distributions of rainfall and evaporation stations that provide the data used to force models, as well as stream flow gauging stations to provide the data for establishing models and for evaluating their success. Hydrological models are faced with a number of challenges which include poor input data (data quality and poorly quantified human activities on observed stream flow data), uncertainties associated with model complexity and structure, the methods used to quantify model parameters, together with the difficulties of understanding hydrological processes at the catchment or subbasin. Within hydrological modelling, there is currently a trend of dealing with equifinality through the evaluation of parameter identifiability and the quantification of uncertainty bands associated with the predictions of the model. Hydrological models should not only focus on reproducing the past behaviour of a basin, but also on evaluating the representativeness of the surface and subsurface model components and their ability to simulate reality for the correct reasons. Part of this modelling process therefore involves quantifying and including all the possible sources of uncertainty. Uncertainty analysis has become the standard approach to most hydrological modelling studies, but has yet to be effectively used in practical water resources assessment. This study applied a hydrological modelling approach for understanding the hydrology of a large Tanzanian drainage basin, the Great Ruaha River that has many areas that are ungauged and where the available data (climate, stream flow and existing water use) are subject to varying degrees of uncertainty. The Great Ruaha River (GRR) is an upstream tributary of the Rufiji River Basin within Tanzania and covers an area of 86 000 km2. The basin is drained by four main tributaries; the Upper Great Ruaha, the Kisigo, the Little Ruaha and the Lukosi. The majority of the runoff is generated from the Chunya escarpment, the Kipengere ranges and the Poroto Mountains. The runoff generated feeds the alluvial and seasonally flooded Usangu plains (including the Ihefu perennial swamp). The majority of the irrigation water use in the basin is located where headwater sub‐basins drain towards the Usangu plains. The overall objective was to establish uncertain but behavioural hydrological models that could be useful for future water resources assessments that are likely to include issues of land use change, changes in patterns of abstraction and water use, as well the possibility of change in future climates

Emerging forms of social action in urban domestic water supply in South Africa and Zimbabwe

This paper compares and contrasts emerging forms of social action in urban domestic water supply in South Africa and Zimbabwe. Both countries represent transitional societies that are facing challenges of providing clean and safe domestic water to the black majority population, which for decades was denied basic social services because of a racist ideology. In the first instance the paper assesses whether there exists a constitutional provision that guarantees the right to water. It then turns to how that is enforced, and what happens in its absence. Lastly the paper examines whether the various interventions lead to improved access to safe water. In South Africa an awareness of the constitutional right to water backed by a supportive legislative framework, which engendered a strong sense of entitlement, caused residents to resort to the courts and direct action such as street protests. Similar initiatives were also observed in Zimbabwe. However, the absence of a conducive legal environment, and disenchantment with the state as a provider of social services, led residents to resort to self reliance in order to access water. In both countries social action was not organic –it tended to be championed if not sponsored either by civil society or party political actors. There was no evidence of improved access to safe water as a consequence of social action. The paper concludes that social action in the urban domestic water supply faces the common challenges of social mobilization in particular and social movements in general.Web of Scienc