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Introduction Savory is considered one of the most important medicinal plants, which is used in various food and medical industries. Nitrogen (N) plays a major role on the growth and yield of medicinal plants. Therefore, an adequate supply of N is required for successful production of savory. However, the application of chemical N fertilizers is associated with many obstacles such as groundwater pollution, N enrichment of surface waters, and drop in the quality of plants. Accordingly, nowadays, great attention has been paid to organic fertilizers. In this regard, humic acid-based fertilizers have shown promising results. Humic acids (HAs) could be converted into nitrohumic acids (NHAs) through the nitration process, in which nitro groups (NO2) are located on the aromatic rings. This process increases the N content of the HA. Thus, NHAs can be used as organic N fertilizers in the cultivation of medicinal plants whose organic production is a priority. However, the effects of these types of fertilizers on plant growth and physiological characteristics have not been well understood. Accordingly, the present study for the first time investigates the effectiveness of NHA on the morphological and physiological characteristics of savory, as well as N loss through leaching. Materials and Methods In the current study, HA was initially extracted from leonardite (purchased from Yazd Golsang Kavir Company) as a rich source of HA. Then, NHA was prepared through the nitration process using nitric acid (50% by volume). After that, using FT-IR (Fourier transform infrared spectroscopy) and CHNS analysis the extracted HA and NHA were characterized, and their N content was determined. Afterward a greenhouse experiment in a completely randomized design (CRD) with three replications was conducted to determine the effects of 16 treatments, including control (without urea, HA and NHA), urea (U1, U2 and U3), humic acid (HA1, HA2 and HA3), nitrohumic acid (NHA1, NHA2 and NHA3), urea-humic acid (U1HA1, U2HA2 and U3HA3), and urea-nitrohumic acid (U1NHA1, U2NHA2 and U3NHA3) on the morphological and physiological characteristics of savory plant. The treatment levels were determined as 40, 80, and 120 mg N kg-1 for the first, second and third level of the treatments, respectively. In the combined treatments of urea and HA or NHA, an equal fraction of the total nitrogen (N) was applied. At the end of the experiment, standard methods were used to assess various characteristics, including root length, leaf area, plant height, root volume, wet and dry weights of shoot and root, leaf chlorophyll index, concentrations of phosphorus, potassium, nitrogen, nitrate, and nitrate reductase in both the shoot and root. Additionally, leaching was conducted on specific days during the experiment, and the leachate was collected for nitrate measurement. Results and Discussion The results showed that using the nitration process, some characteristics of the NHA such as total acidity, the content of carboxylic and phenolic groups as well as N content improved as compared to the initial HA. Moreover, the results indicated that most of the morphological and physiological traits of savory plants, including leaf area, plant height, root length, fresh and dry weights of root and shoot as well as chlorophyll index, and the concentration of nitrogen, phosphorous, potassium, nitrate and nitrate reductase enzyme were significantly higher in the NHA treatments than those of HA. In addition, the highest shoot dry weight was obtained in the combined treatments of U3NHA3 and U3HA3 as well as in the U3 treatment alone. The average rate of nitrate concentration increase in the U treatments was 1.77 times higher than the UNHA treatments. According to the results, U3 treatment indicated the highest nitrate loss which by using the U3NHA3 treatment, the mean concentration of nitrate in the leachate decreased by about 40.5% as compared to the U3 treatment. Conclusion The findings of this research revealed that most of the morphological and physiological traits of savory plant showed better responses to the combined treatments of U3NHA3 and U3HA3 as well as to the U3 treatment alone. However, with regard to the lower accumulation of nitrate in the shoot of savory as well as to the lower nitrate leaching, the combined treatments were preferred. Accordingly, NHA can be a alternative nitrogen source in increasing the yield and growth indicators of savory. However, the reasons behind the fact of the better performance of combined nitrogen treatments than the individual ones require more research in the future. [ABSTRACT FROM AUTHOR]

Background and Objective: Aloe vera (Aloe barbadensis M.) as a medicinal herb is practiced in wound healing. This study was carried out to assess the effect of Aloe vera gel (mucilage) on TGF-β gene expression in incisional skin wound in BALB/c mice. Method: In this experimental study, 36 BALB/c male mice with weight range 22±2 gr were allocated equally into negative control (no wound), sham-operated (wound treated with physiological serum) and teratment (wound treated with Aloe vera gel). Two equal full-thickness skin wounds of 10±2mm were made on either side of the vertebral column in the sacral region. The animals in the teratment group were received daily, 2 gram of Aloe vera gel (without any bandage) as a thin layer for a period of 16 days. On 8th and 16th post wounding day, TGF-β gene expression in incisional wounds and Malonyldialdehyde (as end-product of lipid peroxidation) in serum samples was measured using RT-PCR and spectrophotometry methods, respectively. Results: TGF-β gene expression in incisional skin wound increased in Aloe vera gel treated group in compared to negative control and sham-operated groups (P

The effect of clay and chain extender on the nonisothermal, isothermal crystallization kinetics, and morphology of polylactide (PLA) was investigated in this study. PLA and PLA-based nanocomposites containing 2 wt% organoclay were prepared via melt compounding. Three commercially available chain extenders were used: polycarbodiimide (PCDI), tris(nonylphenyl) phosphite (TNPP), and Joncryl ADR4368F. The nanoclay particles were found to act as nucleating agents. Chain extender incorporation, however, had diverse effects on both crystallization rate and degree of crystallinity. Nonisothermal DSC results revealed that the addition of PCDI increased the cold-crystallization temperature ([T.sub.c]) from 106 to 114 °C, reduced the degree of crystallinity from 6.3 to 5.3%, and resulted in the formation of bimodal melting peaks in PLA. On the other hand, the reduction of chain ends in the presence of TNPP resulted in a significant increase of the crystallization rate and degree of crystallinity from 6.3 to 15.2%. In the case of Joncryl, its incorporation led to the formation of a long-chain branching structure, which disrupted the chain packing. Therefore, the degree of crystallinity (from 6.3 to 1.6%) and the rate of crystallization decreased, while [T.sub.c] was increased from 106 to 122 °C in the presence of Joncryl. POLYM. ENG. SCI., 53:1053-1064, 2013. © 2012 Society of Plastics Engineers, INTRODUCTION The environmental impact of petroleum-based polymers and their waste management has motivated their substitution by more environmentally benign products. The most common biodegradable polymers are polylactic acid (PLA), polycaprolactone [...]

This study aimed to assess the effect of incubation time and sewage sludge on peppermint biomass, essential oil yield, and Zinc (Zn), lead (Pb), and Cadmium (Cd) concentrations in the plant tissues as well as assessing phytoremediation potential of peppermint grown in contaminated calcareous soils. A greenhouse experiment was conducted by growing peppermint (Mentha pipertia L.) in two contaminated soils treated with three levels of sewage sludge (0, 10, and 30 g kg-1) over two incubation times (30 and 120 days). Results revealed an increase in plant biomass and essential oil yield with an increase in incubation time and the sewage sludge amount. The concentrations of Zn, Pb, and Cd in plant tissues increased significantly in all treatments, except Cd concentration in plants growing on 10 g kg-1 of sewage sludge and incubated for 120 days. No traces of Zn, Pb, and Cd were found in essential oil of plants treated with 10 g kg-1 of sewage sludge. In other treatments, the concentrations of these metals in the essential oil were found within the limits recommended for medicinal plants. Unlike the bioaccumulation factor, the translocation factor of the studied metals decreased with an increase in the sewage sludge amount and incubation time. Although peppermint was not a sustainable plant to lower the pollution load, as the biomass production increased significantly and metals concentrations in essential oil remained within the recommended limits in all treatments, it can be concluded that peppermint can be used for cultivation in contaminated soils treated with sewage sludge. [ABSTRACT FROM AUTHOR]

Fluorine doped tin oxide (FTO) thin films were deposited onto glass substrate at different substrate temperatures by a simple and inexpensive method of air pressure chemical vapor deposition. The substrate temperature was kept constant at about 500°C as the optimum temperature, and air was used as both a carrier gas and the oxidizing agent. A very simple method of characterization were carried on to investigate the electrical and structural properties of the prepared thin films. The electrical parameters variations showed that these parameters vary with substrate temperature ranging from an insulator thin film to a highly conductive layer. X-ray diffraction also revealed the structure to be polycrystalline at higher temperatures compared to amorphous structure for lower temperatures. [ABSTRACT FROM AUTHOR]