Similar Mineral Content Research Articles

New Symptoms in Castanea sativa Stands in Italy: Chestnut Mosaic Virus and Nutrient Deficiency

The European chestnut characterizes both the landscape and economy of mountainous Italian areas. In recent years, new canopy disorders have been reported: “chestnut yellows”, often ascribed to phytoplasma and/or nutrient deficiency, and “chestnut mosaic”, associated with a virus (ChMV). Therefore, research was carried out in four Italian regions to describe the two symptomatic frames and assess their etiology. Surveys were conducted on 101 chestnut trees (23 with mosaic, 38 with yellowing, and 40 without symptoms). The phytosanitary status was monitored, and the new canopy disorders were detected, distinguishing between yellowing and mosaic. Moreover, leaf samples were collected for molecular and nutrient analyses. No phytoplasma infection was recorded, while ChMV was detected in 91.3% of samples with mosaic symptoms, 31.6% of yellowing samples, and 30.0% of asymptomatic samples. Yellowing was associated with Mn deficiency. On the other hand, ChMV-infected and healthy leaves had similar mineral contents, showing that mosaic symptoms are induced by the virus. Both disorders negatively affected photosynthesis efficiency. These phytosanitary problems are present in Italian chestnut woods and cause local effects, and a relationship with other biotic and abiotic factors can be hypothesized. Considering the increase in new records, these symptoms represent an emerging issue whose impact and spread need to be further monitored.

Waste Nutrient Solution as an Alternative Fertilizer in Curled Mallow Cultivation

To determine the feasibility of reusing waste nutrient solution as an alternative fertilizer for vegetable production, we investigated the growth and shoot nutrient content of curled mallows (Malva verticillata L.) irrigated with tap water (pH 7.8, EC: 0.5 dS·m-1), nutrient solution (pH 5.7, EC: 2.7 dS·m-1) and waste nutrient solution (pH 5.0, EC: 2.2 dS·m-1 in average) collected from plant factories. Three waste nutrient solutions were applied in sequential order to a waste nutrient solution treatment and mineral compositions of irrigation solutions were analyzed. We measured the total number of leaves, fresh and dry weight, chlorophyll content (SPAD value) and total phenolic content of curled mallow shoots and analyzed shoot and soil nutrient content using inductively coupled plasma-optical emission spectrometer (ICP-OES). Curled mallows were harvested twice during the cultivation. Curled mallows irrigated with waste nutrient solutions had a similar fresh weight (yield), total phenolic content and number of leaves compared to those grown with fresh nutrient solution, and had higher fresh and dry weight, chlorophyll content (SPAD value) and percentage dry weight compared to those grown with tap water upon first and second harvest. The dry weight of curled mallows grown in waste nutrient solution was lower than that of plants grown in nutrient solution on first harvest, but there was no significant difference between the waste nutrient solution and nutrient solution groups on second harvest. Curled mallows irrigated with nutrient solution and waste nutrient solution showed similar mineral content. These results suggest that waste nutrient solution in curled mallow cultivation could be reused and provide more efficient and sustainable nutritional solutions that improve the productive yields of crops in the agriculture sector.

Microtomographic analysis of controlling parameters on permeability and elastic velocities of black shales

Shales are sedimentary rocks characterized by their very fine grain size, and are basically composed of clays and silts. Important features of shales are their fissility, presenting thin layers almost always parallel to their bedding, low permeability and elastic velocities which can vary significantly, but whose controlling factors are not yet well understood. X-ray microtomography (microCT) is a widely-used technique to reconstruct the internal pore space of rocks and other materials. In this work parameters controlling permeability and elastic velocities of black shales are investigated through x-ray microCT digital image analysis. Results show that black shale permeability is controlled mainly by pore size distribution and pore connectivity, while elastic velocities of such rock type are controlled by porosity, pore size and the quality of grain–grain contacts. Mineral composition of the analyzed rock samples does not affect this analysis since all the samples have similar mineral content. MicroCT images show clearly the predominant pore locations along the fissility planes, which is a determinant factor in the difference between elastic velocities of horizontal and vertical rock samples. The macropores of the analyzed rock samples are not well interconnected, in contrast with the micropores, which present high pore connectivity and capillary pressure. A quality index for grain–grain contacts is proposed here which is the dominant factor controlling the elastic velocities of the analyzed black shale samples, followed by macro and micro porosities. Vertical samples, whose elastic velocities are lower than those of horizontal ones, present low values for the quality index of grain–grain contacts.

Synthesized Hydroxyapatite Powder from Clamshell via Chemical Precipitation Method

Hydroxyapatite (HAp) is a kind of bioceramic based material that has been used extensively in many medical applications. Owing to nearly similar mineral contents to natural bone, the material has been accepted as an implant in order to improve the osteointegration with the bone tissue. In this work, an alternative processing route from waste materials, namely clamshell in producing HAp powder is presented. The effects of processing temperatures, ranging from 750°C to 950°C and pH values, ranging from 6.5 to 8.5 on the synthesized HAp prepared via chemical precipitation method were investigated. From the XRD, FTIR and EDX results, it was observed that the lowest pH value of 6.5 with the temperature of 850°C is the optimum parameters to synthesize HAp.

Effects of laser-aided circumferential supracrestal fiberotomy on root surfaces

To evaluate and compare the effects of circumferential supracrestal fiberotomy in vivo (using diode, CO(2), and Er∶YAG lasers) on the morphology and chemical composition of the root surface. Forty healthy premolar teeth, intended for extraction for orthodontic reasons, were used in this study. Root surfaces were treated using different laser methods, as follows: (1) control; (2) Er∶YAG laser (2.94 µm, 100 mJ, 10 Hz); (3) diode laser (808 nm, 1.2 W, continuous wave); and (4) CO(2) laser (10.6 µm, 3 W, continuous wave). Subsequently, the teeth were removed and subjected to scanning electron microscopic (SEM) examination and energy dispersive x-ray (EDX) spectrometric analysis. SEM analysis indicated that no thermal changes, including melting or carbonization, were observed following the lasing procedures. EDX analysis showed that the laser procedures resulted in similar mineral contents (weight % of calcium and phosphate) as compared to those in the control group. Based on these findings, we concluded that laser-aided procedures, when used at appropriate laser settings, preserve the original morphology and chemical composition of cementum.

Effects of root planing procedures with hand instrument or erbium, chromium:yttrium–scandium–gallium–garnet laser irradiation on the root surfaces: a comparative scanning electron microscopy study

The purpose of this study was to investigate the efficiency of hand instrumentation and laser irradiation on calculus removal from the root surfaces, in vitro. Thirty-two human teeth, extracted for periodontal reasons, were used in this study. Root surfaces of single-rooted teeth were treated by different methods including (1) conventional hand instruments; (2) hand instruments and tetracycline-hydrochloride (Tet-HCl); (3) erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation, setting I (short pulse); (4) Er,Cr:YSGG laser irradiation, setting II (long pulse). Three premolar teeth, extracted for orthodontic reasons, served as control. The morphology of the root surfaces was evaluated by light and scanning electron microscopy. Energy dispersive X-ray (EDX) analysis was performed to compare the mineral content of root surfaces treated with hand instrumentation and lasing procedures. The results of this study demonstrated that all treatments were efficient in calculus removal from the root surfaces. Thermal changes, including melting and carbonization, were not observed in either lasing procedure. The surface was rougher in the laser groups than in the groups treated with hand instruments. Moreover, roughness was greater in the long-pulse laser setting than in the short-pulse setting. While increased calcium (Ca) and decreased phosphate (P) (weight concentration percent) were observed in all treatments when compared with the control, laser procedures resulted in a more similar mineral content than in the groups treated with hand instruments. Based on these findings, laser procedures, when used in appropriate settings, are capable of performing scaling and root planing in the treatment of periodontitis. It may be concluded that short pulse laser may be more suitable for the micro-morphology of the root surface. However, additional in vitro and clinical studies are necessary to clarify the success of laser in periodontal therapy.

Modelling and optimization of hydrocyclone for iron ore fines beneficiation — using optical image analysis and iron ore texture classification

A new modelling technique for simulating hydrocyclone performance has been developed, in which particles in every size fraction of the feed ore are classified based on ore texture type, taking into account that the same ore texture types in every size fraction of the feed ore have similar mineral contents and densities. Mineral tracking by optical image analysis and newly-developed texture classification software was used in this technique to classify the feed ore particles by texture type and to determine the average particle density of each class in every size fraction. Particle density calculations took into account the reduction of porosity with reduction of particle size and the effect of different imaging magnifications for different size fractions. The data obtained about each class in every size fraction was used to create a virtual feed which was input to the hydrocyclone model to simulate the ore processing performance. For model validation, pilot-scale hydrocyclone beneficiation experiments were performed on an iron ore blend, using different hydrocyclone pressures and percent solids in the feed pulp. Model parameters were determined from one set of experimental results and the calibrated model was then used to predict the outcomes of the two subsequent experiments. Comparisons of the model and experimental results are presented and discussed. This new approach enables prediction of the recovery of each mineral and texture type in the products, calculation of the total product iron grade and recovery, and optimisation of the hydrocyclone performance for a given ore.

Geological controls on natural ecosystem recovery on mine waste in southern New Zealand

Slopes of an abandoned waste rock at Wangaloa coal mine, south-east New Zealand, have naturally developed variable vegetation cover over the last 40–60 years. Three distinct areas of revegetation can clearly be identified: dense cover, patchy cover, and largely unvegetated, and the differences in revegetation success are directly related to the physical properties of different rock types making up the waste rock substrate. The colonizing plants have become established in largely unweathered rock with essentially no soil development. Quartz gravel and siltstone waste rock are the two principal rock types forming substrates for revegetation. The quartz gravel has clasts up to 3 cm, and was derived from the coal-bearing sequence. Siltstone was largely derived from a Quaternary loess cap on the coal mine area. These two substrates have similar mineral contents, and this mineral material provides the low level of available nutrients. However, there is little difference in nutrient status or trace element load of the different substrates, and differences in cohesion, moisture content, and proportion of quartz pebbles control revegetation success. Finer grained matrix has been flushed from quartz gravel waste rock by rain water, leaving a dry surface armour layer of quartz pebbles. This surface layer inhibits plant establishment, so quartz gravel waste rock remains largely unvegetated. Erosion creates deep rills, and steep surfaces creep downslope. In contrast, full vegetation cover was established on the siltstone waste rock that was cohesive and did not erode. Patchy revegetation was localized by siltstone in mixed quartz gravel and siltstone substrate. Invertebrate diversity and distribution were closely linked to the spatial patterns of revegetation. The rate of revegetation and ecosystem recovery was primarily dependent on the proportion of siltstone waste rock in the last dumped truck load. A quartz pebble content <15% is optimal for plant establishment.

Structural and nanoindentation studies of stem cell-based tissue-engineered bone

Stem cell-based gene therapy and tissue engineering have been shown to be an efficient method for the regeneration of critical-sized bone defects. Despite being an area of active research over the last decade, no knowledge of the intrinsic ultrastructural and nanomechanical properties of such bone tissue exists. In this study, we report the nanomechanical properties of engineered bone tissue derived from genetically modified mesenchymal stem cells (MSCs) overexpressing the rhBMP2 gene, grown in vivo in the thigh muscle of immunocompetent mice for 4 weeks, compared to femoral bone adjacent to the transplantation site. The two types of bone had similar mineral contents (61 and 65 wt% for engineered and femoral bone, respectively), overall microstructures showing lacunae and canaliculi (both measured by back-scattered electron microscopy), chemical compositions (measured by energy dispersive X-ray analysis), and nanoscale topographical morphologies (measured by tapping-mode atomic force microscopy imaging or TMAFM). Nanoindentation experiments revealed that the small length scale mechanical properties were statistically different with the femoral bone (indented parallel to the bone long axis) being stiffer and harder (apparent elastic modulus, E∼27.3±10.5 GPa and hardness, H∼1.0±0.7 GPa) than the genetically engineered bone ( E∼19.8±5.6 GPa, H∼0.9±0.4 GPa). TMAFM imaging showed clear residual indents characteristic of viscoelastic plastic deformation for both types of bone. However, fine differences in the residual indent area (smaller for the engineered bone), pile up (smaller for the engineered bone), and fracture mechanisms (microcracks for the engineered bone) were observed with the genetically engineered bone behaving more brittle than the femoral control.

The effect of 'fibre-filler' (F-plan diet) on iron, zinc and calcium absorption in rats.

1. The availability of iron, zinc and calcium in a diet containing 400 g 'fibre-filler' (a mixture of bran, fruit and nuts, used in the F-plan diet)/kg diet (HF diet) was measured by whole-body counting in rats, using 59Fe, 65Zn and 47Ca as extrinsic labels, and compared with a diet of similar mineral content but no 'fibre-filler' (LF diet). Absorption of Fe and Ca was significantly higher from the HF than from the LF diet but there was no difference in Zn availability between the two diets. 2. The ability of rats given LF or HF diets for 3 or 28 d to absorb Fe, Zn and Ca was measured using ferrous sulphate, zinc chloride and calcium chloride in a cooked starch-sucrose (1:1 w/w) paste, extrinsically-labelled with the appropriate isotope. There was no difference in Fe absorption between the HF- and LF-fed groups but both Zn and Ca absorption were higher in LF- than in HF-fed animals after 3 and 28 d. 3. The mineral status of the animals given HF or LF diets for 28 d was examined, and there were no differences in blood haemoglobin, liver and bone Zn and plasma and bone Ca levels. The total liver Fe was significantly lower (P less than 0.05) in the HF-fed animals. 4. It was concluded that 'fibre-filler' did not have an adverse effect on Fe, Zn or Ca metabolism in rats although the long-term effect on Fe status warrants more detailed investigation. Further work is required to extend these studies to man.