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The presence of microalgae affects water quality and beneficial uses of surface freshwaters. Chitosan with proven potential for harvesting specific microalgae species from their culture medium to produce biofuels and bioproducts also appears promising for efficient removal of mixed microalgae species from surface freshwaters. The main focus of the present study was on removal of mixed microalgae species using chitosan as a coagulant to help improve water quality. Important operational parameters were optimized for economical microalgae removal. The microalgae cells, chlorophyll-a, total nitrogen, and total phosphorous removal efficiency were 82.06%, 89.90%, 69.32%, and 44.01%, respectively, at an optimum chitosan dose of 10 mg/L, pH 8, slow mixing time 7 min, slow mixing rate 30 rpm, and settling time of 15 min. The results show that chitosan coagulation efficiently removed mixed microalgae species from surface freshwater with significant improvement in water quality and recovery of algal biomass for other beneficial applications. Key words: chitosan, microalgae harvesting, flocculation, water quality improvement, microalgal biomass. La presence de microalgues a une incidence sur la qualite de l'eau et les utilisations benefiques des eaux douces de surface. Le chitosane, avec un potentiel confirme en matiere de recolte d'especes precises de microalgues a partir de leur milieu de culture pour la production de biocarburants et de bioproduits, semble egalement prometteur pour l'elimination efficace des especes mixtes de microalgues des eaux douces de surface. L'objectif principal de la presente etude etait d'eliminer les microalgues mixtes en utilisant le chitosane comme coagulant pour ameliorer la qualite de l'eau. Des parametres operationnels importants ont ete optimises pour l'elimination economique des microalgues. L'efficacite d'elimination des cellules de microalgues, de chlorophylle-a, d'azote total et de phosphore total etaient 82.06, 89.90, 69.32 et 44.01 %, respectivement, a une dose optimale de chitosane de 10 mg/L, pH 8, temps de melange lent 7 min, vitesse de melange lente 30 rpm et temps de sedimentation de 15 min. Les resultats ont montre que la coagulation du chitosane a permis d'eliminer efficacement les microalgues mixtes des eaux douces de surface, ce qui a permis d'ameliorer considerablement la qualite de l'eau et de recuperer la biomasse algale pour d'autres applications benefiques. Mots-cles : chitosane, recolte de microalgues, floculation, amelioration de la qualite de l'eau, biomasse de microalgues., 1. Introduction Excessive growth of microalgae, especially cyanobacteria, in surface freshwaters forms unsightly surface scum, causes severe oxygen depletion and fish mortalities upon die-off, releases algal toxins, taste and odour, [...]

The regioselective benzoyloxylation process involves stirring a mixture of phenyl/benzyl-sulfanyl/selenylethanoate 1a-c with appropriate oxidant [benzoyl peroxide (BPO) 2a/ m-chloroperbenzoic acid (m-CPBA) 2b /bis(p-methoxybenzoyl peroxide) (BPM-BPO) 2c] under catalysis of hydrated copper acetate in toluene at 60 °C/RT. Regioselective C–H functionalization of esters 1a-c leads to benzoyloxy substituted phenyl/benzyl-sulfanyl/selenylbisesters 3a-g in good to excellent yields (80–95%). Variably substituted trans-3-phenylsulfanyl-β-lactams 4 employed for C3-H functionalization with BPO 2a generates diastereoisomeric mixture of trans- and cis-3-benzoyloxy-3-(phenylsulfanyl)-β-lactams 5 and 6 as major and minor isomers after efficient column chromatographic purification. The structural confirmation was done using IR, 1H NMR, 13C NMR, DEPT-90 NMR spectroscopic analysis and CHNS elemental analysis. In vitro antibacterial and antifungal evaluations on bisesters suggest benzylselenyl-bisester 3c as potent antimicrobial agent. Out of trans- and cis-3-benzoyloxy-β-lactams 5a and 6a, the trans isomer 5a was active against all microbial strains whereas the cis isomer 6a was completely inactive. [ABSTRACT FROM AUTHOR]

A wide variety of bacteria are present in soil but in rhizospheric area, the majority of microbes helps plant in defending diseases and facilitate nutrient uptake. These microorganisms are supported by plants and they are known as plant growth-promoting rhizobacteria (PGPR). The PGPRs have the potential to replace chemical fertilizers in a way that is more advantageous for the environment. Fluoride (F) is one of the highly escalating, naturally present contaminants that can be hazardous for PGPRs because of its antibacterial capacity. The interactions of F with different bacterial species in groundwater systems are still not well understood. However, the interaction of PGPR with plants in the rhizosphere region reduces the detrimental effects of pollutants and increases plants' ability to endure abiotic stress. Many studies reveal that PGPRs have developed F defense mechanisms, which include efflux pumps, Intracellular sequestration, enzyme modifications, enhanced DNA repair mechanism, detoxification enzymes, ion transporter/ antiporters, F riboswitches, and genetic mutations. These resistance characteristics are frequently discovered by isolating PGPRs from high F-contaminated areas or by exposing cells to fluoride in laboratory conditions. Numerous studies have identified F-resistant microorganisms that possess additional F transporters and duplicates of the well-known targets of F. Plants are prone to F accumulation despite the soil's low F content, which may negatively affect their growth and development. PGPRs can be used as efficient F bioremediators for the soil environment. Environmental biotechnology focuses on creating genetically modified rhizobacteria that can degrade F contaminants over time. The present review focuses on a thorough systemic analysis of contemporary biotechnological techniques, such as gene editing and manipulation methods, for improving plant-microbe interactions for F remediation and suggests the importance of PGPRs in improving soil health and reducing the detrimental effects of F toxicity. The most recent developments in the realm of microbial assistance in the treatment of F-contaminated environments are also highlighted. [ABSTRACT FROM AUTHOR]

A field experiment with wheat was conducted at Pusa (25.98°N, 85.67°E, 52 m amsl), Bihar (middle Gangetic plains of India), to assess the responses of phenology, yield attributes, and yield to growing season temperature and heat stress. For this purpose, wheat was planted on five dates (viz., 15 November, 25 November, 5 December, 15 December, and 25 December) for three consecutive years (viz., 2014-2015, 2015-2016, and 2016-2017)with three prominent cultivars of the region (viz., RAU-3711, HD-2824, and HD-2733). Five dates of sowing represent different wheat-growing micro-environments as imposed by varying sowing dates encompassing the entire sowing window. The study observed the significant effect of sowing dates on phenophase duration. In general, with progress in the date of sowing, tiller initiation was delayed, while the reverse trend was observed for later growth phases. Sowing environments significantly influenced the number of effective tillers m-2. Average numbers of effective tillers (ET) m-2 for the wheat sown during 15-25 November were almost 11.6% higher than those of the 25 December sown crop. Grain filling duration (GFD) showed a declining trend with the advancement of sowing dates due to increased thermal load on the crop during the reproductive period. 15 November planted crop exhibited the highest GFD (47 days), which was shortened significantly beyond 25 November, signifying agrometeorological non-suitability of wheat sowing beyond this window. Wheat sown on 25 November recorded the highest grain yield (3.21 Mg ha-1), 48.61% higher than the 25 December sown crop due to the congenial thermal regime. In this context, we have identified optimal and sub-optimal conditions to escape heat stress for higher wheat productivity. Moreover, the sumof deviation of temperature fromoptimumthresholds, computed for sensitive growth phases (50% flowering to physiological maturity), helped us to identify heat stress and its impact on wheat. Genotype-by-environment (GGE) biplot analysis revealed that RAU-3711 was found to be themost stable cultivar. A decrease in the yield of wheat by 4.9% to 12.0%, sown during November, and 33.8% to 42.4%, sown during December, is predicted in 2050-51 and 2080-81, respectively, under RCP 4.5. [ABSTRACT FROM AUTHOR]

Excessive growth of microalgae results in the eutrophication and degradation of water quality in lakes and ponds. Microalgae have proved to be very beneficial for sustainable development. Its applications, starting from growth to death, make them a valuable resource for food and energy production. However, presence of microalgae in surface water sources affects water quality and its beneficial uses. The excess nutrient-rich agriculture runoff also adds problems to the downstream systems. Nutrient removal and microalgae harvesting are considered the most problematic task for improving water quality of surface waters. The main objective of the present study was to improve the water quality of nutrient rich waters using attached growth systems. The use of batch and continuous flow baffled attached growth systems has successfully improved the water quality and produced algal biomass that can be utilized or transformed into other valuable products. The performance of continuous flow baffled attached growth system was better and it improved the quality of oligotrophic, mesotrophic, eutrophic and hypereutrophic waters by removing>95% of TN and TP in 35, 63, 63 and 4 days, with biomass productivity of 2.69 ± 0.21, 3.17 ± 0.06, 3.61 ± 0.16 and 4.64 ± 0.3 gDWm−2 day−1, respectively. [ABSTRACT FROM AUTHOR]

The polarimetric synthetic aperture radar (PolSAR) provides us with a two-by-two scattering matrix data set. The ensemble averaged coherency matrix in an imaging window derived using a scattering matrix has all non-zero elements in its three-by-three matrix. It is a full 3 × 3 matrix that bears nine real-valued and independent polarimetric parameters inside. In the proposed decomposition method, G5U, we preprocess observed coherency matrix [T] by using two consecutive unitary transformations to become an ideal form for five-component decomposition. The transformation reduces nine parameters to seven, which is the best fit for five-component scattering model expansion. We can retrieve five powers corresponding to surface scattering, double bounce scattering, volume scattering, oriented dipole scattering, and compound dipole scattering, directly. These powers can be calculated easily and used to display superb polarimetric RBG images as never before, and are further applicable for polarimetric calibration, classification, validation, etc. [ABSTRACT FROM AUTHOR]

Featured Application: Particle degradation of biomass materials can be a severe issue in transportation and material handling because of dust generated. Especially for pneumatic conveying systems, assessment of material degradation in such a large process can be challenging. In this study, the degradation of wood pellets and dry roasted coffee beans in a pneumatic conveyor was evaluated for high-speed impacts. The change in particle size and generation of fine particles were used as an indicating parameter for the degradation. A four-bends industrial scale conveying system was used for the degradation study in lean phase pneumatic conveying. The effects of operating parameters on the degradation were investigated, including the conveying velocity of particles and particle concentration. The experimental results showed that the degradation and the fines generation increased with an increase in particle velocity. An opposite trend was observed with an increased solid concentration in the pipeline. It was found that the two types of wood pellets traveled at different particle velocities with the same operating conditions, which resulted in significant differences in the degradation. Compared to the wood pellets, roasted coffee beans were found to travel at air velocity. In conclusion, the degradation in a pneumatic conveying system is complex and challenging to evaluate because there are many influential factors, such as the type of materials, equipment, and operation conditions. Early assessments in a laboratory will be beneficial to evaluate the degradation at all controlled operative conditions. [ABSTRACT FROM AUTHOR]

Objective: To determine the availability and affordability of a healthy food basket and to model how those on low-incomes might manage. Design and methodology: After determining access and availability of key items from shops in two localities, called Deepdale and Ingol, a healthy food basket was developed. From this a week's healthy menu was devised for a mother and two children, then availability of the ingredients was checked using data collected from the shops and costed. The baskets represented the cultural preferences of White British and South Asian families informed by participatory work with both these groups. We chose the income level for a family entitled to income support and child allowance. Results: Analysis of the availability of some healthy options such as brown bread, wholemeal pasta, and brown rice showed they were not widely available within shops in the two areas. The price of the "White British" basket in the area of Ingol was 70.61 British Pounds (lowest price). For comparable goods in the area of Deepdale, using the most expensive shopping basket, the price for the same basket was 42.47 British Pounds. A South Asian family shopping at a major supermarket outlet in Deepdale would pay 47.05 British Pounds. Using local shops they could pay between 38.59 British Pounds and 44.28 British Pounds by seeking out the best bargains in five shops (including some top-up items from a national supermarket). At the time of the research a mother with two children entitled to income support and child allowance would have to spend 28-32 per cent of her income in local shops and 34 per cent in a supermarket to buy a basket of healthy goods. This compared to the national average of 10-12 per cent of income being spent on food purchases. Conclusions: Prices varied enormously between the two areas. Local shops in one area offered a comparable price to shopping in the supermarkets. The Ingol area, with a large white working class population, was particularly poorly served for those on low incomes and the range of choices restricted. The percentages spent on food to meet the requirements of our healthy baskets and menus show that more than the national average--in both absolute and relative terms--would have to be spent to eat healthily. For the vulnerable and price dependent poor in Preston this will mean having to spend more on food and possibly more on travel to access basics, a healthy diet will cost more, while proportionally an unhealthy diet, as can be found in fast food outlets, may not be as expensive when other costs such as cooking are taken into account. An overall rise in food prices of 5 per cent will reduce living standards among high-income consumers by approximately 3 per cent; for low-income consumers this reduction in an already poor diet could be as high as 20 per cent. What we have demonstrated is the usefulness of local studies to highlight micro-differences in relatively small areas (Preston city) and the different experiences of groups in accessing healthy foods, and thus the need to refine interventions at a local level. (Contains 3 tables.)

Objectives: To map food access in the city of Preston in the north-west of England in order to determine access, availability and affordability of healthy food options. Design and methodology: The research design employed a number of distinct methods including: surveys of shops; interviews with local people and shopkeepers; a cost and availability survey of shops in two deprived areas of Preston--Deepdale and Ingol--the former with a majority South Asian population; and the use of geographical information systems to map access and availability. Results: (1) Preston had more fast food outlets (186) [not including restaurants who operate takeaways] than general groceries outlets (165). (2) There were more local shops selling affordable food in the area with the high South Asian population than in Ingol with its white working class population. There were clear gaps in provision and access in the white working class area (Ingol), with shops being more than 500 metres away from where people lived. Shops in this area stocked more familiar "British foods" and less specialist or fresh produce. (3) Analysis of the availability of some healthy options such as brown bread, wholemeal pasta and brown rice showed that they were not widely available within shops in the two areas. (4) The price of the "White British" basket in Ingol was 70.61 British Pounds (cheapest price). For comparable goods in Deepdale, using the most expensive shopping basket, the price for the same basket was 42.47 British Pounds. (5) A South Asian family shopping at a major national supermarket outlet in Deepdale would pay 47.05 British Pounds. Using local shops they could pay between 38.59 British Pounds and 44.28 British Pounds by seeking out the best bargains in five shops (including some top-up items from a national supermarket). (6) At the time of the research a mother with two children, entitled to income support and child allowance, would have to spend 28-32 per cent of her income in local shops and 34 per cent in a supermarket to buy a basket of healthy goods. Conclusions: There is a need to engage proactively with the location of shops in urban areas, to ensure they offer a healthy range of options and are sited near to where people live. The number of fast food outlets needs to be controlled and the food they offer improved.This latter issue of the number of outlets and quality of fast food contributes to an overall obesogenic environment. Access to food is heavily dependent on having access to a car; local shopping and the quality of food on offer are important for key groups such as those on benefits, the elderly, single parents and others with limited access to a car. Proactive policy solutions may lie with the engagement of health agencies with the planning processes in local authorities to ensure that the food retail environment reflects a healthy choice. Local area agreements between health agencies and local authorities offer a way forward, in that they can take into account the expressed needs of local residents. (Contains 1 table and 3 figures.)

The world of Alice Walker's fiction is peopled with an amazing variety of men and women responding to the challenges of life in different ways. The present paper analyzes those characters, in Alice Walker's The Temple of My Familiar, who appear to be living at a low level of awareness and sensitivity, stumbling through the pains and pressures of life in a rather hopeless and hapless manner. Such characters find it too difficult to face the challenges posed by the conditions of their existence and succumb to their pressures by suffering silently and submitting passively to the forces of oppression. [ABSTRACT FROM AUTHOR]

Glacier velocity is an important parameter to characterize glacier dynamics and to derive ice thickness and mass balance. The 2-pass/3-pass Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques are advantageous in estimating glacier movements. However, the 2-pass DInSAR requires an external Digital Elevation Model (DEM), whereas the 3-pass DInSAR does not. The 3-pass DInSAR technique is adopted with Sentinel-1A/1B to map the Svalbard glacier flow velocities. Furthermore, the effect of glacier surface elevation change on the 2-pass DInSAR results were revealed by comparing glacier velocity with the two time period topographic information. The coherence indicates that Sentinel-1A/1B has a high potential to infer operational glacier velocity using the 3-pass DInSAR method with an average atmospheric uncertainty of 0.24cm/day over the studied region. The precision of the 3-pass DInSAR is analyzed by comparing 2-pass derived line-of-sight (LOS) velocity on the same dates. The 3- pass DInSAR achieves high-resolution and detailed information. [ABSTRACT FROM AUTHOR]