Reduce Water Evaporation Research Articles

Characteristics of fly ash based concrete prepared with bio admixtures as internal curing agents

Concrete is the most widely used material which is structural and versatile in nature owing to its heterogeneous and complex structures. Curing of concrete is an important stage to attain its intended strength and durability. The conventional method of water curing is not very effective and sometimes ignored due to water scarcity and labour problems. Internal curing of concrete by adding water soluble material can hold the mixing water against evaporation and further enhance the hydration of cement. The chemical admixture namely polyethylene glycol (PEG) is able to reduce water evaporation by a retaining function, lead to strong and durable concrete without water curing but it is expensive. This paper presents an attempt of using bio materials namely Spincea oleracea (S. oleracea) &Calatropis gigantea (S. oleracea) as internal curing agents in concrete. To confirm the presence of hydroxyl or ether group in S. oleracea and S. oleracea like PEG for water retention, UV–visible and FT-IR studies are carried out on these plant extracts. To evaluate their internal curing property, FT-IR, XRD and SEM analysis are carried out on M20 grade fly ash based concrete powder sample with internal curing agents and compared with the performance of conventionally water cured concrete powder samples. Compressive strength and bond strength of concrete with bio admixtures are compared with the internal curing property of PEG and also with conventionally water cured concrete.

A low-cost, composite collagen-PDMS material for extended fluid retention in the skin-interfaced microfluidic devices

The advancement of soft, wearable microfluidic devices relies on the microfabrication of polydimethylsiloxane (PDMS) using soft lithography techniques. However, thin 3D microstructures made of PDMS limit long-term storage of aqueous samples and reduce the accuracy of onboard sensing modalities within the platform because of the material's high permeation of water vapor. We studied a composite material of collagen microparticles and PDMS that greatly reduces water evaporation while maintaining the properties of a soft elastomer required for skin-interfaced microfluidics. The collagen-PDMS material is biocompatible, affordable, and non-toxic. We reduced permeability by 80.2% by building a film containing 30 wt% collagen microparticles. Mechanical properties, such as elastic modulus and bonding efficacy, can vary as a function of particle concentration in the films. The skin-interfaced collagen-PDMS microfluidic devices increase sweat retention by 45% through 9 h compared with pure PDMS. This material can greatly improve the long-term sample storage of epidermal devices.

From Food Waste to Innovative Biomaterial: Sea Urchin-Derived Collagen for Applications in Skin Regenerative Medicine.

Collagen-based skin-like scaffolds (CBSS) are promising alternatives to skin grafts to repair wounds and injuries. In this work, we propose that the common marine invertebrate sea urchin represents a promising and eco-friendly source of native collagen to develop innovative CBSS for skin injury treatment. Sea urchin food waste after gonad removal was here used to extract fibrillar glycosaminoglycan (GAG)-rich collagen to produce bilayer (2D + 3D) CBSS. Microstructure, mechanical stability, permeability to water and proteins, ability to exclude bacteria and act as scaffolding for fibroblasts were evaluated. Our data show that the thin and dense 2D collagen membrane strongly reduces water evaporation (less than 5% of water passes through the membrane after 7 days) and protein diffusion (less than 2% of BSA passes after 7 days), and acts as a barrier against bacterial infiltration (more than 99% of the different tested bacterial species is retained by the 2D collagen membrane up to 48 h), thus functionally mimicking the epidermal layer. The thick sponge-like 3D collagen scaffold, structurally and functionally resembling the dermal layer, is mechanically stable in wet conditions, biocompatible in vitro (seeded fibroblasts are viable and proliferate), and efficiently acts as a scaffold for fibroblast infiltration. Thus, thanks to their chemical and biological properties, CBSS derived from sea urchins might represent a promising, eco-friendly, and economically sustainable biomaterial for tissue regenerative medicine.

Effect of using pruning waste as an organic mulching on a drip-irrigated vineyard evapotranspiration under a semi-arid climate

ABSTRACT In a drip-irrigated vineyard soil evaporation (E) can reach up to 30-40% of the seasonal grapevine crop evapotranspiration (ETc). Vineyard soil management can be used as a technique to reduce soil E for improving crop water use efficiency. The aim of this experiment was to analyze the effect of using pruning waste as an organic mulching on vineyard ETc. During three experimental seasons, several cycles of grapevines water use determinations were conducted using a large weighing lysimeter located in Albacete (southeast Spain) under drip irrigation. Measurements were carried out under different soil management practices: i) keeping the bare soil within the lysimeter during the first 2-3 days (bare soil), ii) covering the lysimeter soil surface with pruning waste as an organic mulching (about 5 cm thick) for the next 2-3 days (organic mulch), and iii) covering the lysimeter with a waterproof canvas (plastic mulch), similar in colour to the soil, for the last 2-3 days of each measurement cycle. In 2017, the measurements period was initiated when midday stem water potential (Ψstem) values reached -1.3 MPa, in order to study the effect of the different soil management on grapevine ETc when vines in the lysimeter were suffering from severe water stress. During the 3-year study, plant determinations (i.e., canopy cover and the phenological stage) showed that vines were at the same stage of development during each period of measurements. Under equal evaporative demand and fractional canopy cover, results showed a reduction in the vineyard ETc between 16-18% with the organic mulching, and up to 24-30% with the plastic mulching. Even though plastic mulches significantly reduced water evaporation from soil surface, this reduction could have resulted in an increase in crop transpiration (T). However, results in this experiment show that both organic and inorganic mulching did not increase vine T compared to no mulching conditions, based on vine T values estimated during the three experimental periods of 2015. Therefore, using pruning waste as an organic mulch could be an environmental friendly alternative to reduce soil evaporation and increase crop water productivity in large areas where vineyards are drip-irrigated.

Analyzing the film formation mechanism of cellulose nanoparticles (CNPs) based on the fast freeze-drying morphology

The aim of this study was to discern the film formation mechanism of cellulose nanoparticle suspensions (CNP suspensions) by transforming the film formation process to be a water evaporation process, investigating the fast freeze-drying morphology of CNPs, the resulting natural formation structure, and the relationship of CNPs and water molecules. It was found that an increasing aspect ratio transforms CNPs from the oriented arrangement to a distributed network. Hydrogen bonds and van der Waals forces among CNPs led to a close and interactive film formation process, contributing to various microstructures in the resultant films. High aspect ratios in CNPs hindered the formation of interaction as well as increased absorbed water on CNPs. The interaction among CNPs, and the interaction between CNPs and water molecules were reflected in shear-thinning behavior of CNP suspensions. High aspect ratio CNPs had the capacity of absorbing more immobilized water, partially leading to a higher viscosity. The microstructures of CNP films were fund to be dense without significant layers or holes and varied from the fast freeze-drying morphology, due to the continuous volume reduction in water evaporation. Overall, it is expected that discerning the film formation mechanism of CNPs provide guidance for controlling the film structure and explaining the macroscopic property of the resultant materials.

Next Generation Salivary Lubrication Enhancer Derived from Recombinant Supercharged Polypeptides for Xerostomia.

Insufficient retention of water in adsorbed salivary conditioning films (SCFs) because of altered saliva secretion can lead to oral dryness (xerostomia). Patients with xerostomia sometimes are given artificial saliva, which often lacks efficacy because of the presence of exogenous molecules with limited lubrication properties. Recombinant supercharged polypeptides (SUPs) improve salivary lubrication by enhancing the functionality of endogenously available salivary proteins, which is in stark contrast to administration of exogenous lubrication enhancers. This novel approach is based on establishing a layered architecture enabled by electrostatic bond formation to stabilize and produce robust SCFs in vitro. Here, we first determined the optimal molecular weight of SUPs to achieve the best lubrication performance employing biophysical and in vitro friction measurements. Next, in an ex vivo tongue-enamel friction system, stimulated whole saliva from patients with Sjögren syndrome was tested to transfer this strategy to a preclinical situation. Out of a library of genetically engineered cationic polypeptides, the variant SUP K108cys that contains 108 positive charges and two cysteine residues at each terminus was identified as the best SUP to restore oral lubrication. Employing this SUP, the duration of lubrication (Relief Period) for SCFs from healthy and patient saliva was significantly extended. For patient saliva, the lubrication duration was increased from 3.8 to 21 min with SUP K108cys treatment. Investigation of the tribochemical mechanism revealed that lubrication enhancement is because of the electrostatic stabilization of SCFs and mucin recruitment, which is accompanied by strong water fixation and reduced water evaporation.

Performance analysis of a 10 MWp utility scale grid-connected canal-top photovoltaic power plant under Indian climatic conditions

Photovoltaic modules installed on water bodies save large land areas but climatic conditions for such solar power plants, are different due to their proximity to flowing water.Thus it is important to study the performance of a canal-top solar PV plant for its reliable operation. In the present study, energetic, exergetic performance and reliability analysis of a 10 MWp grid-connected canal-top PV plant, is studied using more than 2 years data. The average monthly performance ratio, system efficiency and exergy efficiency of the plant, are found to be 0.78, 11.90% and 12.03%, respectively. PV degradation rate is found to be higher than land based power plants. The average monthly exergy efficiency, useful thermal exergy convective heat transfer loss and exergy destruction during monitoring period, are found to be 12.03%, 18.32%, 1% and 58.65%, respectively. The performance of present plant is found to be slightly lower than land based PV plants. The possible solutions to improve output power generation by canal-top PV plants are discussed. The water saved due to reduced water evaporation is found to be about 95 million litres per year.Further follow up research areas are identified to enhance the reliability of such power plants installed over water bodies.

Variation in amylose concentration to enhance wheat flour extrudability

Composition and functionality of five waxy wheat (Triticum aestivum L.) genotypes were elaborately investigated and related to end-product attributes of extrudates. As such, the interaction between starch biopolymers and protein in extrusion processing could be studied. Furthermore, the effect of an increasing amylose-concentration was studied by the use of blends. Waxy genotypes absorbed more water, gave rise to stiffer doughs and had higher onset and peak gelatinization temperature. In contrast, a lower pasting temperature and final viscosity and higher peak viscosity and breakdown could be observed. The volume percentage of small starch granules showed to be negatively correlated with peak temperature and positively with final viscosity and holding strength as well as with extrudate hardness. This was also positively correlated with amylose concentration. Expansion index was highest at a slightly decreased amylose concentration of 16.6%. Markedly higher moisture content for all amylose-free extrudates was attributed to a combination of increased solubility of amylopectin and reduced water evaporation at die emergence. It was hypothesized that an interplay with protein content and composition was laying at the basis of the observed differences. Moreover, the altered pasting behavior of waxy wheat may enhance the extrudability of gluten containing wheat flour.Starch granule size distribution is related to extrudate texture. Amylose content affects expansion index, water absorption and texture of extrudates. Interaction between starch content and protein composition and quality was observed. Waxy genotypes are strongly varying in their protein composition and functionality. Maximum expansion was obtained for blends containing 25% waxy flour.

Transepidermal Water Loss Value Comparison Between Tengkawang and Durian Seed Oil Lotion

Body epidermis has an important health function to prevent body dehydration. This research aims to compare Transepidermal Water Loss (TEWL) values between durian seed oil and tengkawang oil. Skin that had been applied with tengkawang oil and durian seed oil lotion were tested for irritation and TEWL values. The tengkawang oil had an acid number of 17 g/mol and contained 8.54 % free fatty acid, while the durian seed oil had an acid number of 6.34 g/mol and contained 2.89 % free fatty acid. Irritation testing was done using lotion containing 100 % of each oil. TEWL analysis on skin applied with the tengkawang oil lotion after 1 hour showed that the lotion could reduce epidermal water evaporation by 35.23 % compared to the skin condition before treatment. Epidermal water evaporation reduction at the second, third and fourth hours after the tengkawang oil lotion application was 31.33 %, 33.93 % and 27.9 %, respectively. TEWL analysis on skin applied with the durian seed oil lotion after 1 hour showed that the lotion could reduce epidermal water evaporation by 11.34 % compared to the skin condition before treatment. Epidermal water evaporation was reduced 14.64 %, 10.53 % and 2.99 % at the second, third and fourth hours after application of the durian seed oil. Based on these results, it can be concluded that tengkawang oil gives better TEWL values compared to durian seed oil.

Evaluation of the efficiency of irrigation methods on the growth and survival of tree seedlings in an arid climate

Scarce and scattered precipitation in arid regions is detrimental for newly planted seedlings. It is essential to provide required water storage for seedlings in restoration projects in the first year of their establishment. The subsurface irrigation can be much more effective than the surface irrigation because of the regulation of water availability and reduction in water evaporation. We studied the effect of surface and subsurface irrigation methods on the growth and survival of four common tree species including heaven tree (Ailanthus altissima (Mill.) Swingle), China berry (Melia azedarach L.), white mulberry (Morus alba L.), and black locust (Robinia pseudoacacia L.) by installing underground clay reservoirs with different permeabilities in Isfahan City, Iran. Different amounts of animal manure and wheat straw were mixed with clay fraction and cooked in a pottery kiln at 900°C to produce reservoirs with different permeabilities. The experimental treatments consisting of irrigation and tree species were considered with a factorial arrangement in a completely randomized design with three replications in 2016 and 2017. Leaf water potential of seedlings, which is indirectly related to drought resistance, was measured by a portable pressure chamber. The results showed that saplings height, basal diameter, number of leaves, chlorophyll content and stomatal conductance were significantly (P<0.05) higher in the subsurface irrigation with low permeability than in the surface irrigation, but the number of branches of the studied species were not significantly (P>0.05) affected by the irrigation methods and different permeabilities of clay reservoirs. The clay reservoirs with low and medium permeabilities constantly provide better conditions for plant growth, and water with lower pressure and longer time intervals to the plant roots as compared with the reservoirs with high permeability. Analysis of variance of the data showed that year and interaction between year and permeability of reservoir had significant effects (P<0.05) on all growth parameters, except for the chlorophyll content. In addition, the highest percentage of survival was 100% associated with the subsurface irrigation and the control treatment had the lowest survival percentages of 60%, 70%, 80% and 100% for M. alba, M. azedarach, A. altissima and R. pseudoacacia, respectively. Finally, the values of leaf water potential showed that R. pseudoacacia was the most drought resistant species.

Plastic-film mulch cropping increases mineral-associated organic carbon accumulation in maize cropped soils as revealed by natural 13C/12C ratio signature

Plastic-film mulch is used for increasing soil temperature and reducing water evaporation to enhance productivity in semiarid regions worldwide; however, its effects on soil organic carbon (SOC) level and stability are not clear. We tested hypotheses that increasing soil temperature and moisture by plastic-film mulch with an increase of carbon input would increase the accumulation of heavy-fraction SOC (HFOC) and decrease the mineralization potential of HFOC. Soils were sampled at 0–45 cm depth from four treatments: (i) no mulch and no straw incorporation, (ii) mulch only, (iii) straw incorporation only, and (iv) straw incorporation plus mulch. All treatments were cultivated with C4 maize (Zea mays L.) under ridge–furrow management continuously for nine years in a field previously planted with C3 crops in a cold environment. Proportionately to the increased aboveground biomass, root biomass in the 0–20 cm depth increased under mulch compared to no mulch. Nine years later, mulch reduced both maize-derived (new) and C3-crop-derived (old) light-fraction SOC (LFOC) stocks only at 0–15 cm soil depth compared to no mulch, regardless of whether straw was incorporated or not, reflecting the increased decomposition due to increased temperature and moisture in mulched soils. Mulch increased new HFOC stock at 0–30 cm soil depth relative to no mulch. These indicated that the faster decomposition of labile LFOC with increasing plant input under mulch relative to no mulch was paralleled by an enhancement in the accumulation of stable HFOC in mulched soils. Mulch enhanced the benefits of straw incorporation in terms of increasing the accumulation of new HFOC. Over nine years, the average sequestration rate of new HFOC at 0–45 cm soil depth was 204 (±18) and 266 (±10) kg ha−1 yr−1 without and with mulch, respectively, in non-straw-incorporated plots, and 514 (±14) and 752 (±18) kg ha−1 yr−1 without and with mulch, respectively, in straw-incorporated plots. Old HFOC was unaffected by mulch or straw incorporation. Overall, mulch did not change the total SOC storage in the top 45-cm soil. Mulch decreased the mineralization potential of new HFOC under laboratory incubation compared to no mulch, indicating that the new HFOC was more decomposed in mulched soils. We concluded that increasing soil temperature and moisture by using plastic-film mulch with high plant input increases the accumulation of stable HFOC in maize croplands.

Effect of nanomaterials on the mechanical properties and microstructure of cement mortar under low air pressure curing

Initial curing is very important for the mechanical properties and durability of cement-based materials. Buildings located in high altitude areas have been exposed to low air pressure and low humidity for a long time, which makes the water inside the buildings move to the outside continuously, thus affecting the service life of the buildings. In this study, nano-SiO2 and nano-Al2O3 are introduced into cement to study the mechanical properties and microstructure of cement mortar under low relative humidity (60% RH) and low air pressure (50 kPa, 60 kPa, 70 kPa). Compressive strength, flexural strength, mass change, pore structure and hydration products are studied. The results show that the hydration degree and strength of the cement specimens cured in low air pressure and low humidity environments decrease. The mass loss and porosity increase, and the number of harmful pores (50~200 nm) increase. However, the existence of nanomaterials can compact microstructure, cut off connected capillary channels, so as to reduce water evaporation, increase the degree of cement hydration, and finally improve the flexural and compressive strength.

Modeling the Interaction of Plastic Film Mulch and Potato Canopy Growth with Soil Heat Transport in a Semiarid Area

Plastic film mulch is an important agricultural technology to reduce water evaporation and modify the soil thermal conditions for crop production. The optical properties of plastic film mulch and the crop canopy growth are both key factors impacting soil heat transport in the soil-film-canopy-atmosphere ecosystem. In this study, a process-oriented model was developed to better understand the interaction among the plastic film mulch, potato (Solanum tuberosum L.) canopy growth, and soil thermal conditions. Canopy growth, photosynthetically active radiation transmittance, net radiation, soil heat flux, and temperature were monitored in a two-year plastic mulch field experiment in Wuwei (Gansu Province, China). Results showed that the simulation of daily soil surface temperature had a good performance with 2.8 and 1.5 °C of root mean square error (RMSE) for the transparent film mulch (TM) and black film mulch (BM), respectively. Moreover, the simulation of the daily net radiation and soil heat flux model indicated reasonable fluctuations with potato phenological development with the daily R2 ranging from 0.89 to 0.98 in 2014 and 2015 for the TM and BM treatments. It was shown that the canopy temperature under BM was greater than that in TM treatment, and the maximum value difference could be up to 7 °C during the early potato growing period, which implied that the BM may perform better in modifying the canopy thermal condition. The model could provide heat distribution information for plastic film choosing in potato field to avoid heat stress.

Experimental Study on Compressive Strength, Water Retention And Water Absorption of self-curing Concrete With Different Curing Conditions

Curing of concrete is maintaining satisfactory moisture content in concrete during its early stages in order to develop the desired properties. « However good curing is not always practical in many cases, therefore the need to develop self-curing agents attracted several researchers ». « The concept of several self-curing agents is to reduce water evaporation from concrete and hence increase the water retention capacity of concrete compared to conventional concrete, the use of self-curing agent is very important from the point view that water resources are getting valuable every day ». This project summarizes various aspects of self-curing of concrete which can be of valuable assistance in adopting good construction practices at site. M25 grade concrete cube specimens prepared based on the standards and availability of materials without and with 30% of flyash and quarry dust replaced as cement and fine aggregate and cubes cured by covering them with a external self-curing compound BONDIT CURE WB, air dried and normal water. These specimens are then tested after 7,14 and 28 days to obtain the compressive strength in three different conditions. The compressive strength of concrete cubes is calculated and compressive strength of self-curing concrete is compared with the different conditions. At the end of curing period of 7,14 and 28 days the amount of water retained in self cured concrete cubes is calculated and compared with the air dried cubes. Water absorption test is conducted on air dried concrete and self cured concrete cubes and the amount of water is absorbed is calculate and compared.

How eyelashes can protect the eye through inhibiting ocular water evaporation: a chemical engineering perspective.

Bionics is a fascinating subject that has inspired many inventions through learning from biological structures and functions. In this work, a coupled multi-physics model has been developed to characterize ocular water evaporation with realistic eyelash structures taken into account. From a chemical engineering perspective, the protective function of human eyelashes in terms of evaporation inhibition has been rationally revealed. Systematic investigations were carried out to elucidate the effects of different eyelash lengths, orientations and inlet air directions on water evaporation on the ocular surface. The results clearly demonstrate that regardless of inlet air directions and eyelash orientations, increasing eyelash length from zero to an optimal length can effectively reduce water evaporation. However, further increase in the eyelash length can lead to enhanced evaporation. For the normal and parallel inlet air directions, the optimal eyelash length is around 15-30% of the eye width and can offer approximately 10-30% evaporation reduction when compared with the cases without eyelashes. These values are independent of the eyelash orientation. This investigation provides valuable data for in-depth understanding of the protective function of the eyelashes, which can be used in the future to improve and optimize bionic designs inspired by human eyelashes.

Facile preparation of Janus polymer film and application in alleviating water crisis

Water scarcity has been becoming a global water crisis, which has threatened the sustainable development of world economic. In this contribution, it will be reported that Janus polymer film can help us coping with this water crisis through water collection and water evaporation suppressing. A sodium maleate grafted polypropylene (PP-g-NaMA) film was fabricated by solvent induced self-assembly, which has one side hydrophobic and the other side superhydrophilic. In addition to low cost, high performance and excellent stability, the newly developed Janus film can be used for water evaporation reduction and water collection, both with very high efficiency. The durable film can also be recycled easily after using. It is unquestionable that the new finding reported in this paper provides a new avenue to alleviate the water crisis in the world.

Effect of polysaccharide derived from Osmunda japonica Thunb ‐incorporated carboxymethyl cellulose coatings on preservation of tomatoes

Polysaccharides from Osmunda japonica Thunb (Op) exhibit a wide range of biological activities including antibacterial, anti-inflammatory, antioxidant, and antitumor effects. Carboxymethyl cellulose (CMC) is a type of cellulose derivative that can form dense films. CMC can slow the respiratory transpiration of tomatoes and reduce water evaporation. Coatings of CMC (0.7% concentration) with various levels of Op (0.02%, 0.04%, 0.06%, 0.08%, and 0.1%) were used to preserve tomatoes at room temperature. The treatment, weight loss, hardness, titratable acidity (TA), respiratory intensity, and concentrations of ascorbic acid, polyphenol oxidase, and malondialdehyde (MDA) were evaluated in tomatoes after 0, 5, 10, 15, 20, and 25 days of storage. Compared with untreated tomatoes, the tomatoes with Op-incorporated CMC coatings had reduced respiratory intensity, weight loss and ascorbic acid loss, increased TA, controlled MDA, and inhibited the decay of tomatoes. Therefore, the use of Op-incorporated CMC coatings extended the shelf life and maintained the quality of postharvest tomatoes. Practical applications In the past decades, the use of edible coatings has attracted widespread interest in extending the shelf life of particularly perishable foods. Currently, applications of edible coatings have been proven to be promising as a tool to improve the quality and extend the shelf life of various fruits. But there have been no reports on the effect of Op-incorporated CMC treatment on the postharvest quality of tomatoes during storage. The purpose of this work is to investigate the efficiency of Op-incorporated CMC treatment to extend shelf life and provide theoretical guidance for the preservation of tomatoes.

Solar Eclipses and the Surface Properties of Water

During four solar eclipse events (two annular, one total and one partial) a correlation was observed between a change in water surface tension and the magnitude of the optical coverage. During one eclipse, evaporation experiments were carried out which showed a reduction in water evaporation at the same time as a rise in the surface tension. The changes did not occur on a day without a solar eclipse and are not correlated to changes in temperature, pressure, humidity of the environment. The effects are delayed by 20, 85, 30 and 37 min, respectively, compared to the maximum eclipse. Possible mechanisms responsible for this effect are presented, the most likely hypothesis being reduced water/muon interaction due to solar wind and cosmic radiation blocking during an eclipse. As an alternative hypotheses, we propose a novel neutrino/water interaction and overview of other, less likely mechanisms.

Overexpression of a Wheat Aquaporin Gene, TdPIP2;1, Enhances Salt and Drought Tolerance in Transgenic Durum Wheat cv. Maali.

In this study, we generated transgenic durum wheat cv. Maali overexpressing the wheat plasma membrane aquaporin TdPIP2;1 gene under the control of PrTdPIP2;1 promoter or under the constitutive PrCaMV35S promoter. Histochemical analysis of the fusion PrTdPIP2;1::TdPIP2;1::GusA in wheat plants showed that the β-glucuronidase (GUS) activity was detected in the leaves, stems and roots of stably transformed wheat T3 plants. Our results showed that transgenic wheat lines overexpressing the TdPIP2;1 gene exhibited improved germination rates and biomass production and retained low Na+ and high K+ concentrations in their shoots under high salt and osmotic stress conditions. In a long-term study under greenhouse conditions on salt or drought stress, transgenic TdPIP2;1 lines produced filled grains, whereas wild-type (WT) plants either died at the vegetative stage under salt stress or showed drastically reduced grain filling under drought stress. Performing real time RT-PCR experiments on wheat plants transformed with the fusion PrTdPIP2;1::GusA, we showed an increase in the accumulation of GusA transcripts in the roots of plants challenged with salt and drought stress. Study of the antioxidant defence system in transgenic wheat TdPIP2;1 lines showed that these lines induced the antioxidative enzymes Catalase (CAT) and Superoxide dismutase (SOD) activities more efficiently than the WT plants, which is associated with lower malondialdehyde and hydrogen peroxide contents. Taken together, these results indicate the high potential of the TdPIP2;1 gene for reducing water evaporation from leaves (water loss) in response to water deficit through the lowering of transpiration per unit leaf area (stomatal conductance) and engineering effective drought and salt tolerance in transgenic TdPIP2;1 lines.

Biogenic synthesis of silver nanoparticles and evaluation of physical and antimicrobial properties of Ag/PVA/starch nanocomposites hydrogel membranes for wound dressing application

Silver nanoparticles (NPs) were synthesized using Diospyros lotus fruit extract. Plant biomolecules were extracted through two solvents i.e. water and methanol. Effect of both solvents on the extraction process as well as effect of both extracts on the reduction of precursor salt to NPs has been studied and reported. Employing the synthesized Ag NPs as a component of nanocomposites, hydrogel membranes were prepared with starch and polyvinyl alcohol (PVA). Synthesized Ag NPs as well as prepared nanocomposites membranes were fully characterized through FTIR, XRD, SEM and UV–Visible spectroscopy. The ultimate tensile strength of the hydrogel membranes with 50 ppm Ag NPs was found to be highest among all the compositions while swelling tendency of the membranes was found to increase with increase in the NPs concentrations. Additionally, no significant decrease in gel fraction of the hydrogel membranes could be observed with the addition of NPs. However, addition of NPs resulted in reduced water evaporation from the membranes. Finally, anti-bacterial test of the Ag NPs as well as hydrogel membranes showed comparable results as shown for the ciprofloxacin, indicating the potential of such membranes to be used in wound dressing application.