Adsorption of Cationic Dyes on a Magnetic 3D Spongin Scaffold with Nano-Sized Fe3O4 Cores

The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe₃O₄ cores is reported here for the first time. The formation of this magnetic spongin–Fe₃O₄ composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe₃O₄ composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe₃O₄ and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe₃O₄ nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.     

Effect of process variables on surface properties of low-pressure plasma treated polypropylene fibers

Plasma surface treatment has been extensively applied in the textile industry for the modification of polymer materials. In this study, polypropylene (PP) fibers in the form of a nonwoven web were treated with low-pressure plasma (air, N₂, Ar) for different treatment time (5–40 min). Powers varied from (50–500 W). Surface properties were studied by measuring wetting time and hydrophilisation diameters after an exposure time of 20 seconds. This study showed that the best conditions for the surface modification of nonwoven PP, with low pressure plasma were a power of 500 W and a treatment time of 30 minutes. Ageing has some effect on the wettability of treated samples.     

Investigation of abundance and determination of dominant species of spider species in Iranian cotton fields

In the present study, density of abundance of spiders explored and dominant species determined in the cotton major fields i.e., Ardebil, Fars, Golestan and Tehran provinces in 2003-2004. Through regular weekly, specimens collected by shaking bushes and they were carried out for the further study to the Araneae laboratory. A total of 632 specimens were classified in 76 species, 59 genera belonged to 19 families. Twenty seven species and 15 genera of them were new records for spider's fauna of Iran. The collected spiders counted and frequency of each species and dominant species determined. The following species Thanatus formicinus (Clerck), Cheiracanthium pennyi (O.P. Cambridge), Aulonia albimana (Walckenaer), Neoscona adianta (Walckenaer) were dominant species in Tehran, Ardebil, Fars and Golestan cotton fields, respectively.     

Indirect Organogenesis through Seedling-Derived Leaf Segments of <Emphasis Type="Italic">Ficus Religiosa</Emphasis> - a Multipurpose Woody Medicinal Plant

The aim of this study is to introduce the suitable protocol for indirect regeneration from seedling-derived leaf segment of Ficus religiosa. The leaf explant successfully produced callus on MS medium containing various concentrations of auxin in combination with BAP. The maximum callus induction (100%) was achieved in MS medium containing 0.5 mg/l 2,4-D plus 0.05 mg/l BAP and MS medium containing 1.5 mg/l NAA plus 0.15 mg/l BAP as well. MS medium consisting of 2,4-D produced yellow-brownish and friable callus (type I) while the yellowish and compact calli (type II) were obtained in MS medium consisting of NAA. On the other hand, MS medium supplemented with IBA formed greenish and compact calli (type Ш). The regeneration rate in type II callus was less than the type I, and there was no shoot induction observed on type Ш calli. MS medium supplemented with 1.5 mg/l BAP in combination with 0.15 mg/l IBA had the highest regeneration frequency (100%) and maximum shoot numbers (5.16) as well as shoot length (2.56 cm) in type I callus. A maximum of 93.33% root induction was observed in MS medium supplemented with 2.0 mg/l IBA plus 0.1mg/l NAA. The plantlets were successfully transferred to the greenhouse. This system could be utilized for large-scale multiplication of Ficus religiosa.     

Geostatistical analysis of soil mechanical properties in Ardabil plain of Iran

This study was conducted to estimate the spatial distribution of penetration resistance (PR), Proctor maximum bulk density (MBD) and critical water content (CWC) as soil mechanical indices. Soil samples to determine sand, silt, clay, organic carbon (OC), CaCO₃, bulk and particle density, total porosity, field water content, MBD and CWC values were collected. Field measurements of PR at 0–10 cm depth were taken from 105 geo-referenced points with 3000 × 3000 m intervals in agricultural lands of Ardabil plain, Iran. Ordinary kriging (OK) and inverse distance weighting (IDW) methods were used to analyze spatial variability of PR, MBD and CWC. The strongest spatial dependences with the lowest ranges of influence were found for OC (7560 m) and MBD (8370 m). The models of fitted semivariograms were Gaussian for PR and MBD, and exponential for CWC. The moderate spatial dependences with the ranges of 13,300 and 40,100 m were found for CWC and PR, respectively. The best prediction according to Lin’s concordance correlation coefficient was obtained by OK for PR (0.48) and IDW for MBD (0.09) and CWC (0.03). These results can be applied in programming of optimum tillage operations for reducing soil compaction risk in the studied region.     

Variation in pathotypes and virulence of Plasmodiophora brassicae populations in Germany

Between 2012 and 2015, 49 new clubroot‐infested fields were identified in 12 German federal states. Clubroot disease incidence varied within these fields from 22% to 92%. Field information revealed that in 85% of fields, oilseed rape was grown in rotation once every 2 or 3 years. Frequency of OSR in the rotation was significantly correlated with the incidence and prevalence of clubroot disease. The disease was detected in fields with soil pH ranging from 5.1 to 8.3, and a significant negative correlation was found between soil pH and the disease incidence of infested fields. Furthermore, more cases of disease and severe incidences were observed in sandy loam and loamy sand as compared with other soil types. Pathotype classification of the 49 Plasmodiophora brassicae populations was conducted on two differential sets, the European Clubroot Differential set and the set of Somé (1996). Additionally, the degree of virulence of the collected isolates was analysed on the clubroot‐resistant oilseed rape cv. Mendel. The results showed variation in pathotype distribution in different regions in Germany. The majority of isolates according to Somé were pathotypes 1 and 3, respectively, with pathotypes 2 and 5 in the minority. Detailed classification according to Buczacki showed the dominance of 16/31/31, 16/14/30 and 16/14/31 populations among 20 distinct virulence patterns of collected isolates. From all populations tested for virulence on cv. Mendel, 15 isolates were found to be moderately or highly virulent. These virulent populations were not restricted to a small geographical area in the country.     

Effects of sulfur application and Thiobacillus inoculation on soil nutrient availability,wheat yield and plant nutrient concentration in calcareous soils with different calcium carbonate content

In this research, elemental sulfur was applied at eight rates with and without Thiobacillus inoculation in calcareous soils which had 23%, 17% and 8.5% Total Neutralizing Value(TNV). The highest grain yield, biological yield, plant height, and concentrations of iron (Fe) and zinc (Zn) in shoot were obtained with application of S⁰ at rates which neutralized 2% and 4% of soil TNV, while highest available nutrients and plant-phosphorus (P) were recorded with application of S⁰ at rates which neutralized 16% and 20% of soil TNV. Maximum indices were recorded in soil which had 17% TNV, so that available P, Fe and zinc (Zn) increased by 167.33%, 35.67% and 81.70% compared with control respectively with application of 9.14 g S° g^?1soil. Thiobacillus inoculation increased all of indices (except Fe concentration) compared with non-inoculated control. The results reveal that sulfur application along with Thiobacillus can increase nutrients availability, nutrients uptake and yield of wheat grown in calcareous soils.     

Identification and Characterization of Random Amplified Polymorphic DNA Markers Linked to a Major Gene (Cr2) for Resistance to Cronartium ribicola in Pinus monticola

ABSTRACT DNA markers tightly linked to resistance (R) genes provide a very powerful tool for both marker-assisted selection in plant breeding and positional cloning of R genes. In the present study, a linkage of random amplified polymorphic DNA (RAPD) markers to the single dominant gene (Cr2) for resistance to white pine blister rust fungus (Cronartium ribicola) was investigated in western white pine (Pinus monticola). A mapping population of 128 individual megagametophytes was generated from seeds of a heterozygous resistant tree (Cr2/cr2), and the corresponding seedlings of each megagametophyte were subjected to the test of phenotype segregation by inoculation with C. ribicola. Bulked segregant analysis and haploid segregation analysis identified eight robust RAPD markers linked to Cr2. This constitutes the first Cr2 genetic linkage map spanning 84.7 cM with four markers only 3.2 cM from Cr2. One sequence (U256-1385) of these linked markers was significantly similar to the Ty3/gypsy-like long terminal direct repeats retrotransposons. Another marker, U570-843, had no significant similarity to any entry in either GenBank or the loblolly genomics data bank. As presumed that the average physical distance per centimorgan is about 10 Mb in P. monticola, it is probably unrealistic to use these DNA markers for positional cloning of the Cr2 gene.