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Abstract Background SRO (Similar to RCD1) genes family is largely recognized for their importance in the growth, development, and in responding to environmental stresses. However, genome-wide identification and functional characterization of SRO genes from cotton species have not been reported so far. Results A total of 36 SRO genes were identified from four cotton species. Phylogenetic analysis divided these genes into three groups with distinct structure. Syntenic and chromosomal distribution analysis indicated uneven distribution of GaSRO, GrSRO, GhSRO, and GbSRO genes on A2, D5 genomes, Gh-At, Gh-Dt, Gb-At, and Gb-Dt subgenomes, respectively. Gene duplication analysis revealed the presence of six duplicated gene pairs among GhSRO genes. In promoter analysis, several elements responsive to the growth, development and hormones were found in GhSRO genes, implying gene induction during cotton growth and development. Several miRNAs responsive to plant growth and abiotic stress were predicted to target 12 GhSRO genes. Organ-specific expression profiling demonstrated the roles of GhSRO genes in one or more tissues. In addition, specific expression pattern of some GhSRO genes during ovule development depicted their involvement in these developmental processes. Conclusion The data presented in this report laid a foundation for understanding the classification and functions of SRO genes in cotton.

Alkaline earth metal oxide (MgO, CaO, SrO) catalysts supported on BEA zeolite were prepared by a wet impregnation method and tested in the transesterification reaction of rapeseed oil with methanol towards the formation of biodiesel (FAMEs—fatty acid methyl esters). To assess the influence of the SiO2/Al2O3 ratio on the catalytic activity in the tested reaction, a BEA zeolite carrier material with different Si/Al ratios was used. The prepared catalysts were tested in the transesterification reaction at temperatures of 180 °C and 220 °C using a molar ratio of methanol/oil reagents of 9:1. The transesterification process was carried out for 2 h with the catalyst mass of 0.5 g. The oil conversion value and efficiency towards FAME formation were determined using the HPLC technique. The physicochemical properties of the catalysts were determined using the following research techniques: CO2-TPD, XRD, BET, FTIR, and SEM-EDS. The results of the catalytic activity showed that higher activity in the tested process was confirmed for the catalysts supported on the BEA zeolite characterized by the highest silica/alumina ratio for the reaction carried out at a temperature of 220 °C. The most active zeolite catalyst was the 10% CaO/BEA system (Si/Al = 300), which showed the highest triglyceride (TG) conversion of 90.5% and the second highest FAME yield of 94.6% in the transesterification reaction carried out at 220 °C. The high activity of this system is associated with its alkalinity, high value of the specific surface area, the size of the active phase crystallites, and its characteristic sorption properties in relation to methanol.

In this research, the effect of strontium oxide (SrO) and hydroxyapatite (HA) on the properties of mineral trioxide aggregate (MTA) have been studied. MTA contained 20% SiO2, 60% CaO, and 2% Al2O3. Bi2O3 and SrO have been added with 18% (w/w) total percentage. MTA was prepared with a sol-gel process using a weak base (NH3) as a catalyst and calcined at 1000 °C for 3 h. The effect of HA was investigated by adding various percentages (3, 6, and 9%) on the MTA modified with 5% SrO. The modified MTA (MTA-SrO-HA) products were hydrated using water with the MTA to water weight ratio of 3:1. The results showed that tricalcium silicate (C3S), dicalcium silicate (C2S), Bi2O3, and strontium silicate peaks were detected in the XRD patterns. An increase in the intensity in the infrared spectra of CaO occurred after hybridization with HA. In addition, bonding of Ca-O-Si appeared at 879 and 995 cm−1, indicating the formation of cement. MTA modified with 5% SrO and 6% HA showed similar compressive strength to the commercial MTA (ProRoot brand). Furthermore, MTA-SrO5/HA6 showed a strong interface interaction with dentin adheres without any gaps, indicating a potential dental material for the future.

Addition of SrO in combination with a hydration technique were used to modify eggshell-derived CaO catalysts for transesterification of Jatropha oil with methanol. A Box-Behnken design of experiment was employed to determine the optimal conditions. The results showed that the maximum methyl ester content of 99.71% could be achieved with the catalyst having 7 mmol/g of SrO at 65 °C, 89.8 min, MeOH:oil molar ratio of 27.6:1, and catalyst amount of 4.77 wt%. At these conditions, the catalyst remained active with methyl ester content of ca. 90% for several cycles and gradually deactivated due to the losses of active metals.

The subsolidus phase equilibria of the CuO – SrO – ZnO system were determined at 900 °C in air. The pseudoternary section does not contain ternary oxide phases but is made of 5 three-phase regions and 2 narrow two-phase regions linked to a Sr14Cu24-xZnxO41-y solid solution. The maximum solubility of Zn in this phase is limited to x ≈ 0.1, but this low doping level results in a significant decrease of the electrical resistivity by about one order of magnitude compared to the undoped compound. The other binary oxide phases SrZnO2,Sr2CuO3, and SrCuO2 do not form solid solutions extending into the ternary system. SrZnO2 was found to decompose upon contact with ambient air.

This research presents a method for computing daily, monthly and annual runoff volume (annual inflow) for Gamesman dam catchment area on Bastora stream in Erbil Governorate. The procedure is developed by the U.S. Soil Conservation Service (SCS) which depends on physical parameters of the catchment area and daily rainfall depth data in Shaqlawa Meteorological station within the catchment area. The advantage of this method is being straightforward to apply, and the physical parameters are easily determined. The runoff depth and volume was computed upon collecting and determining physical parameters (such as drainage area, land uses, soil type and soil infiltration rate) for the catchment area. The results were compared with estimated depth and volume of runoff suggested by (Sogreah) empirical equation used in the design planning report for Gomspan dam prepared by the Project’s Consultancy team. The results of the comparison revealed the fact that the depth and volume of runoff was over estimated in the planning report.

The historical bottleneck for truly high scale integrated photonics is the light emitter. The lack of monolithically integrable light sources increases costs and reduces scalability. Quantum phenomena found in embedded Si particles in the nanometer scale is a way of overcoming the limitations for bulk Si to emit light. Integrable light sources based in Si nanoparticles can be obtained by different CMOS (Complementary Metal Oxide Semiconductor) -compatible materials and techniques. Such materials in combination with Si3N4 photonic elements allow for integrated Si photonics, in which photodetectors can also be included directly in standard Si wafers, taking advantage of the emission in the visible range by the embedded Si nanocrystals/nanoparticles. We present the advances and perspectives on seamless monolithic integration of CMOS-compatible visible light emitters, photonic elements, and photodetectors, which are shown to be viable and promising well within the technological limits imposed by standard fabrication methods.

In the search of a new biomaterial for the treatment of bone defects resulting from traumatic events, an osteoporosis scenario with bone fractures, tumor removal, congenital pathologies or implant revisions for infection, we developed 3D scaffolds based on mesoporous bioactive glasses (MBGs) (85 − x)SiO2–5P2O5–10CaO–xSrO (x = 0, 2.5 and 5 mol.%). The scaffolds with meso-macroporosity were fabricated by pouring a suspension of MBG powders in polyvinyl alcohol (PVA) into a negative template of polylactic acid (PLA), followed by removal of the template by extraction at low temperature. SrO-containing MBGs exhibited excellent properties for bone substitution including ordered mesoporous structure, high textural properties, quick in vitro bioactive response in simulated body fluid (SBF) and the ability of releasing concentrations of strontium ions able to stimulate expression of early markers of osteoblastic differentiation. Moreover, the direct contact of MC3T3-E1 pre-osteoblastic cells with the scaffolds confirmed the cytocompatibility of the three compositions investigated. Nevertheless, the scaffold containing 2.5% of SrO induced the best cellular proliferation showing the potential of this scaffold as a candidate to be further investigated in vitro and in vivo, aiming to be clinically used for bone regeneration applications in non-load bearing sites.

This work is focused on making a correlation between results obtained by using spectroscopy and microscopy techniques from single and twofold-layer Silicon-Rich Oxide (SRO) films. SRO films single-layer and twofold-layer characterizations were compared considering the conditions as-grown and with thermal treatment at 1100 °C for 60 min in a nitrogen atmosphere. The thickness of the single-layer film is 324.7 nm while for the twofold-layer film it is 613.2 nm; after heat-treated, both thicknesses decreased until 28.8 nm. X-ray Photoelectron Spectroscopy shows changes in the excess-silicon in single-layer SRO films, with 10% in as-grown films and decreases to 5% for the heat-treated films. Fourier Transform Infrared Spectroscopy (FTIR) exhibits three characteristic vibrational modes of SiO2, as well as, the vibrating modes associated with the Si-H bonds, which disappear after the heat treatment. With UV−Vis spectroscopy results we obtained the absorbance and the absorption coefficient for the SRO films in order to calculate the optical bandgap energy (Egopt), which increased with heat-treatment. The energy peaks of the photoluminescence spectra were used to calculate the silicon nanocrystal size, obtaining thus an average size of 1.89 ± 0.32 nm for the as-grown layer, decreasing the size to 1.64 ± 0.01 nm with the thermal treatment. On the other hand, scanning electron microscopy and high-resolution transmission electron microscopy images confirm the thickness of the twofold-layer SRO films as 628 nm for the as-grown layer and 540 nm for the layer with heat-treatment, and the silicon nanocrystal size of 2.3 ± 0.6 nm for the films with thermal treatment.

Borate glasses with the basic composition 0.6B2O3·0.2Na2O·0.2CaO and SrO progressively substituting CaO were prepared and characterized for their bone-bonding ability. The obtained glasses were thermally treated and converted to their glass-ceramic derivatives. In this study, FTIR spectral analyses were done for the prepared glasses and glass-ceramics before and after immersion in a sodium phosphate solution for extended times. The appearance of two IR bands within the spectral range 550–680 cm-1 after immersion confirms the formation of hydroxyapatite. X-ray diffraction studies and scanning electron microscope analysis supported the obtained infrared spectroscopy results. The solubility test (measurements of the weight loss in aqueous sodium phosphate solution) was conducted for measuring the dissolution of both glassy and crystalline derivatives to find out the role of SrO. The corrosion behaviour of the glasses and glass-ceramics indicate the increase of weight loss with the increase of SrO content. Different suggested proposals were introduced to explain this abnormal behaviour.

In this paper, we present structural and luminescence studies of silicon-rich silicon oxide (SRO) and SRO-Si 3 N 4 bi-layers for integration in emitter-waveguide pairs that can be used for photonic lab-on-a-chip sensing applications. The results from bi and mono layers are also compared. Two clearly separated emission bands are respectively attributed to a combination of defect and quantum confinement⁻related emission in the SRO, as well as to defects found in an oxynitride transition zone that forms between the oxide and the nitride films, while ruling out quantum-confinement phenomena in the silicon nitride.