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Water treatment for human uses is a vital asset to economic development. This article focuses on a combination of physical, biological, and chemical processes. Methods of water treatment require concrete or steel base structures, rendering them heavy, costly, and time-consuming to establish. Water treatment systems should be economically viable and practicable in design for developing societies; hence, structural builds should be simplified. Novel structures, a series of polyethylene cyclonic ponds for water treatment, were built and tested. Tanks were equipped with a settled material central outlet, water side outlet, and a pump shower system that enabled sludge removal without mechanical intervention. A freely flowing vortex was produced, aerated, given a biological treatment, and finally mixed with a chemical treatment step. Test establishment of the batch system enabled improvement in water quality, with removal performance as follows: TSS (total suspended solids) = 98%, UV254 absorbance = 50%, DOC (dissolved organic carbon) = 56%, and turbidity=95%. The batch system builds of the current study required short construction time and were economically priced. Cyclonic ponds are suited to diverse usage. The value may be felt in the improvement of water quality for human consumption, utility, and ecosystem services to counter the extensive pollution caused by oil and gas extraction and other industries.

In many areas, wastewater feeds water bodies, which leads to it being non-usable for agricultural and other uses. Phytoremediation is a scientific approach which cleans contaminated waters, demanding large areas for application. Vertical agriculture is a new method to compact plant cultures. This study investigates vertical wastewater phytoremediation (VWP). Twenty vetiver grasses were planted in a hydroponic vertical agriculture system. Wastewater flowed into the system in four different flow rates, 60, 80, 100, and 160 l day−1 and water purity was assessed in order to measure the remediation ability of the VWP. Results showed a reduction in biochemical oxygen demand (BOD5 and NO3− concentrations and an increase of electrical conductivity (EC) and dissolved oxygen (DO) in the outlet. Maximum and minimum (BOD5) reduction percentage (78.47% and 67.36%) and NO3− removal percentage (90.53% and 36.41%) occurred in flow rates 60 and 160 l day−1, respectively. With the increase of wastewater flow rate, phytoremediation performance decreased, but the performance of VWP with vetiver grass was efficient enough to enable wastewater remediation. Scaling up VWP with Vetiver and related competitive plant species holds promise for wastewater remediation for both human and ecosystem services.

COVID-19 (coronavirus disease) is a global pandemic that started in China in 2019 and has negatively affected all economic sectors of the world, including agriculture. However, according to estimates in different countries, agriculture has suffered less than other sectors such as construction, industry and tourism, so agricultural development can be a good option to compensate for the economic damage caused to other sectors. The quality of available water and soil resources for agricultural development is not only limited, but is also decreasing incrementally, so the use of saline and unconventional soil and water resources is inevitable. Biosaline agriculture or haloculture is a system in which highly saline water and soil resources are used sustainably for the economic production of agricultural crops. It seems that in the current situation of the world (with COVID-19's impact on agriculture on the one hand and the quantitative and qualitative decline of freshwater and soil on the other), haloculture with a re-reading of territorial capabilities has good potential to provide a part of human food supply. In this review article, the potential of haloculture to offset the adverse impacts of the pandemic is analyzed from five perspectives: increasing the area under cultivation, using unconventional water, stabilizing dust centers, increasing the body's immune resistance, and reducing losses in agribusiness due to the coronavirus. Overall, haloculture is an essential system, which COVID-19 has accelerated in the agricultural sector., Graphical abstract Image 1

Water treatment for human uses is a vital asset to economic development. This article focuses on a combination of physical, biological, and chemical processes. Methods of water treatment require concrete or steel base structures, rendering them heavy, costly, and time-consuming to establish. Water treatment systems should be economically viable and practicable in design for developing societies; hence, structural builds should be simplified. Novel structures, a series of polyethylene cyclonic ponds for water treatment, were built and tested. Tanks were equipped with a settled material central outlet, water side outlet, and a pump shower system that enabled sludge removal without mechanical intervention. A freely flowing vortex was produced, aerated, given a biological treatment, and finally mixed with a chemical treatment step. Test establishment of the batch system enabled improvement in water quality, with removal performance as follows: TSS (total suspended solids) = 98%, UV

In many areas, wastewater feeds water bodies, which leads to it being non-usable for agricultural and other uses. Phytoremediation is a scientific approach which cleans contaminated waters, demanding large areas for application. Vertical agriculture is a new method to compact plant cultures. This study investigates vertical wastewater phytoremediation (VWP). Twenty vetiver grasses were planted in a hydroponic vertical agriculture system. Wastewater flowed into the system in four different flow rates, 60, 80, 100, and 160 l day

Introduction: With increasing of population and the valuable water resource pollutions, a demand has been felt for new and inexpensive methods in order to remediation and improving of water quality. Cadmium is a trace element. In low concentration, this heavy metal is harmful to life, and considered as a dangerous pollutant. Cadmium leads to pollution and reduction of water quality; sometimes even toxicity through contaminated sources such as wastewater (Agricultural, municipal and industrial). Phytoremediation with aquatic macrophytes is an effective and inexpensive method for improving water quality and wastewater. The aim of this study was to investigatethe cadmium phytoremediation by Ceratophyllumdemersum L. as a potential method for remediation of cadmium pollution in aquatic medium. Materials and Methods: In this study, the remediation of cadmium pollution in aquatic medium monitored, within 14 days cultivation of coontail (Ceratophyllumdemersum L.). At first, for estimating the level of local wastewater cadmium pollutions, five-month cadmium concentration measurement of steel industrial wastewater and urban wastewater set. Then, plants collected from the irrigation channels of ShahidChamran University of Ahvaz. After finding the best pH of nutrient solution for Ceratophyllumdemersum L. growth by cultivating the plants in 2 liters pots filled by the solutions withthree different pH(5.5, 7 and 9.5) within three weeks; 12 grams of plants cultivated in 2 liters of Hoagland nutrient solution contaminated by cadmium(pH = 7). The initial contamination levels were setasfive different concentrations of cadmium (0, 1, 2, 4, and 6 mg l-1) with three replications. The cadmium concentrations of the pots were measured every day and on the last day of cultivation, plants wet weight, plants dry weight and Cd concentration in plants weremeasured. Then,biomass production, Cd bioconcentration factor (BCF), Cd uptake index, and Cd uptake percentage of plants were calculated. Standard deviations calculationand correlation and regression analysis were performed using Microsoft Office Excel2007 and SPSS 16. One-way ANOVA performed to identify significant differences in metal concentrations in the different treatments. Differences considered significant atp < 0.05. Results and Discussion: Among three pH (5.5, 7 and 9.5) for plants cultivation, C. demersum L.grewbetter in pH = 7. In fact, the average amount of produced biomasses were 46.6 g (pH = 5.5), 79.6 g (pH = 7) and 68.4 g (pH = 9.5). Therefore, to investigate the Cd remediation, the pH of nutrient solution set equal to 7. The final Cd concentrations in nutrient solution for initial Cd concentrations of 1, 2, 4 and 6 mg l-1 were 0.30, 0.36, 2.76 and 3.85 mg l-11respectively. Moreover, the Cd uptake percentage after 14days cultivation of C. demersum L.in nutrient solution for initial Cd concentrations of 1, 2, 4 and 6 mg l-1 were 70.00, 82.01, 31.00 and 35.83 %respectively. Cd uptake percentage of plants for initial concentrations of 4 and 6 mg l-1weresignificantly lesser than those of 1and 2 mg l-1.The decreased uptake efficiency percentage maybe caused by the effect of Cd toxicity on plant cell membrane permeability and efficiency.The average of BCF in plants for initial Cd concentrations of 1, 2, 4 and 6 mg l-1 were 384.4, 707.9, 66.5 and 75.0respectively. High reduction ofBCF amounts with increasing the initial concentration of 2to 4 and 6mg l-1, maybe caused by cadmium physiological adverse effects on plants. The averages of uptake index in plants were 1.26, 2.95, 2.24 and 3.92 mg for initial Cd concentrations of 1, 2, 4 and 6 mg l-1respectively. The results showed a reduction between 2 and 4 mg l-1concentrations that probablycaused by Cd toxicity disruption on plants uptake mechanism and growth. Moreover, the increase of plants uptake index in initial concentration of 6 mg l-1 could be explain by partial losing of the selective permeability of the plants cell membrane. The maximum (3.60 g/day) and minimum (1.62 g/day) of biomass production related to pollutant concentrations of 0 and 6 mg l-1 respectively, and it shows a greatefect of the Cd on C. demersum L.growth. Conclusion: The plant accumulated cadmium efficiently, and the remediation efficiency was near to 82%. However, the pollutant removal was not complete in a short time.In total, phytoremediation of cadmium and other pollutants from wastewater or other aqueoussolutions by Ceratophyllumdemersum, as a native aquatic plant of most of Iran’s rivers, could be anefficient and appropriatemethod.

The aim of the present study was investigation of two aquatic plants efficiency, duckweed Lemna gibba (floating-leaved hydrophyte) and coontail Ceratophyllum demersum L. (free-floating hydrophyte) on Cd and Ni removal from synthetic aqueous. Both aquatic plants were grown under greenhouse conditions in pots containing a nutrient solution amended with increasing doses of each of the contaminants tested (0, 1, 2, 4 and 6 mg L −1 ) in a completely randomized design with three replications. Plants dry matter production as well as heavy metals and nutrient tissue concentrations were measured at the end of the experiment. The results showed that increasing heavy metal concentrations in nutrient solution caused a decrease in both plants biomasses. L. gibba reduced the contamination level which was up to 91% for Cd and 50% for Ni. In addition, the efficiency of C. demersum was 82.01% for Cd and 52.5% for Ni. L. gibba uptake both heavy metals (5.07 mg for Ni and 9.70 mg for Cd) but C. demersum accumulated both heavy metals (4.5 mg for Ni and 3.87 mg for Cd) less and slower for Cd removal but a little more and faster for Ni than the other plant. The Ni and Cd BCF values for L. gibba ranged between 270.19 to 638.95 and 942.79 to 5093.27, respectively; and for C. demersum ranged between 104.16 to 200 and 75 to 707.92, respectively. The high efficiency of L. gibba and C. demersum in Cd and Ni removal from synthetic medium makes it a proper treatment method.

Phytoremediation with aquatic plants is a new, effective and inexpensive method for improving water quality and wastewater. In this study, Nickel removal by the aquatic plant, coontail (Ceratophyllum demersum L.), native hydrophyte of most of Iran's rivers, was reviewed after optimum growing pH nomination, within 14 days cultivation in contaminated Hoagland nutrient solution, at the four different concentration of nickel (0, 1, 2, 4, and 6 mg L -1 ). With daily analysis of nickel concentration in cultivation solution and also initial and final concentration of this element in plant, nickel phytoextraction potential evaluated, and nickel biological effects on coontail grows with biomass production was studied. Maximum removal efficiency was 50% calculated from 6 mg L -1 metal concentration. Maximum bioconcentration factor and maximum uptake index calculated from 6 mg L -1 metal concentration were 338.65 and 5.05 mg, respectively. Maximum (3.6 g/day) and minimum (1.27 g/day) biomass production index caused from 0 mg L -1 and 6 mg L -1 of pollutant concentrations. Based on the results, nickel phytoremediation of industrial wastewater by coontail is applicable.

The purposes of this paper are to access the level of motivation, adjustment and environmental similarities among expatriate academics in a Malaysian university; and to analyze the influence of demography on satisfaction among expatriate academics in a Malaysian university. Limitation of this study is just focusing on one university of Malaysia. Survey questionnaire have been used to collect the data from randomly selected expatriate academics who currently working in Universiti Teknologi Malaysia (UTM). Only the Nationality is significant differences with satisfaction of expatriate academics in UTM. Expatriate academics are mostly motivated to remain by teaching context which has three items: rapport with departmental leadership, teaching opportunities, and nation building (ability to affect change). Fourteen items as motivation to remain which selected by 50% of the respondents are research opportunities, cost of living, reputation of the university, research funding, reputation of department, research/ lab facilities, international experience, professional development opportunities, geographic location of Malaysia, rapport with departmental leadership, teaching opportunities, nation building (ability to affect change), scholarly environment, and students. Research opportunities and cost of living identify as the most important factors of motivation. Majority of expatriate academics are able to adjust in host country. Expatriate academics are better in specific job responsibilities and supervisory responsibilities. “Everyday customs that must be followed” and “general living conditions (housing, etc.)” are similar from their home country.

The significant contribution to a firm’s long-term success, innovation has burst as one of the most important determinant of organizational performance. Mainly due to the globalization of markets and the extreme and rapid growth of technology has put tremendous pressure on companies to look for new and alternative ways to compete and survive in the current scenario. Numerous academic researches declare that success rate of service innovations is low and there are only few possible explanations for this assertion. In this current study, the innovation literature will be reviewed followed by the different approaches to measure innovation performance. In this study, we attempt to emphasis on importance of further researches in order to effectively measure innovation in hotel industry.

This article represents the differences between expectations and perceptions of service quality among international postgraduate students in UTM by calculating the gap scores in SERVQUAL scale. In addition, this article indicates the service quality dimensions which are evident among these students by using all calculated gap scores in factor analysis. Also, one sample t-test was conducted to find the level of service quality from the perspective of the participants. This study used a modified service quality (SERVQUAL) instrument which was validated by a pilot study and distributed to 353 of international postgraduate students in UTM who were selected by stratified sampling to reach to its results. The results demonstrate the negative gap scores among all 22 items of SERVQUAL scale and it shows that the students’ expectations of service quality are more than their perceived service quality in this university. Additionally, four dimensions, namely tangible, consistency, assurance and compassion, were identified in the SERVQUAL scale. Finally, the low level of service quality is demonstrated from the perspective of international postgraduate students in UTM.