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Erosion processes represent one of the most essential degradation problems, resulting in the waste of valuable resources (soil loss) and pollution (loss of elements). This research aims to study the impacts of four treatments (Tillage, Straw, Corn Stover, Grass) during three seasons (spring, summer, and autumn) on soil physicochemical properties and hydrological response. A rainfall simulator was used (58 mm h − 1 for 30 min) in an intensively managed apple orchard on a Vertisol in Croatia. Portable X-ray fluorescence was employed to determine soil and sediment concentrations of phosporus (P), copper (Cu) and zinc (Zn). Tillage treatment showed lower water stable aggregates and soil organic matter during all three seasons compared to treatments with surface cover. Surface cover affected hydrological response in spring and autumn, thus mitigating time to ponding, time to runoff, runoff, and sediment loss (SL). The summer period was characterized by soil cracking during the dry period, which severely affected hydrological properties, where the infiltration was high enough to mitigate any erosion process. Element losses were positively correlated with SL, thus making them prone to transfer down the slope. Soil water content was highly related to P, Cu, and Zn, affecting their solubility and movement. This study affirmed the positive effects of mulch use and grass cover on the soil properties, hydrological response, and element losses. While these results confirm the positive effects of sustainable management, further investigation is required in terms of experiment duration, to gain precise results to develop a strong strategy in tackling erosion processes. Highlights Integrated soil management enhances erosion control and sustainability in orchards. Intensive agriculture impacts soil health and ecosystem integrity. Seasonal dynamics affect soil and hydrology profoundly. Advanced mulching and grass cover boost soil quality and reduce pollution.

The diffusion of trace elements in mining wastelands has attracted widespread attention in recent years. Vegetation restoration is an effective measure for controlling the surface migration of trace elements. However, there is no field evidence of the effective riparian zone width in mining wastelands. Three widths (5 m, 7.5 m, and 10 m) of Rhododendron simsii/Lolium perenne L. riparian zones were constructed in lead–zinc mining wastelands to investigate the loss of soil, cadmium (Cd), copper (Cu), arsenic (As), lead (Pb), and zinc (Zn). Asbestos tiles were used to cut off connections between adjacent plots to avoid hydrological interference. Plastic pipes and containers were used to collect runoff water. Results showed that more than 90% of trace elements were lost in sediment during low coverage and heavy rainfall periods. Compared with the 5 m riparian zone, the total trace element loss was reduced by 69–85% during the whole observation period in the 10 m riparian zone and by 86–99% during heavy rain periods in the 10 m riparian zone, which was due to reduction in runoff and concentrations of sediment and trace elements in the 10 m riparian zone. Indirect negative effects of riparian zone width on trace element loss through runoff and sediment concentration were found. These results indicated that the wide riparian zone promoted water infiltration, filtered soil particles, and reduced soil erosion and trace element loss. Riparian zones can be used as environmental management measures after mining areas are closed to reduce the spread of environmental risks in mining wastelands, although the long-term effects remain to be determined.

This study carried out the underwater and in-air wire-feed laser deposition of an aluminium alloy with a thin-walled tubular structure. For both the underwater and in-air deposition layers, both were well-formed and incomplete fusion, cracks, or other defects did not exist. Compared with the single-track deposition layer in air, the oxidation degree of the underwater single-track deposition layer was slightly higher. In both the underwater and in-air deposition layers, columnar dendrites nucleated close to the fusion line and grew along the direction of the maximum cooling rate in the fusion region (FR), while equiaxed grains formed in the deposited region (DR). As the environment changed from air to water, the width of DR and height of FR decreased, but the deposition angle and height of DR increased. The grain size and ratio of the high-angle boundaries also decreased due to the large cooling rate and low peak temperature in the water environment. Besides, the existence of a water environment benefitted the reduction of magnesium element burning loss in the DR. The microhardness values of the underwater deposition layer were much larger than those of the in-air layer, owing to the fine grains and high magnesium content.

The micro-scale spatial distribution and loss of carbon, nitrogen and phosphorus were examined in degraded grassland near Ordos, in the Mu Us Sand-land, northwestern China. Five communities that represented a series of successionally degraded stages in desertification were chosen for the work. The dominant plant of Community 1 was the steppe grass Stipa bungeana; Community 2 was dominated by a mix of S. bungeana and the shrub Artemisia ordosia; Community 3 was A. ordosia; Community 4 was a mix of A. ordosia and the desert grass Cynanchum komorovii; and Community 5 was C. komorovii. The soils in root-spheres and in the bare openings between plants in five successionally degraded plant communities were analyzed for total organic carbon (TOC), total nitrogen (TN), inorganic nitrogen (IN), total phosphorus (TP), and available phosphorus (AP). The results showed that the heterogeneity process of the soil chemistry was characterized first by TOC heterogeneity and later by TN heterogeneity. The heterogeneity process of TP was only characterized in the community 3. No significant heterogeneity was present for AP in the five community stages. At the beginning of degradation, invasion by the shrub A. ordosia of S. bungeana grassland was found to lead to competition for soil elements between S. bungeana and A. ordosia and made the Community 2 soil environment temporarily homogeneous. In Community 3, however, the soil elements became spatially heterogeneous, and this led to the development of 'islands of fertility'. The concentrations of soil elements (TOC, TN and IN) were greatest in the shrub root-spheres. With further desertification (from Community 4 to Community 5), the islands of fertility began to collapse, and the concentrations of the main soil elements declined rapidly. The dynamics of soil phosphorus under progressive desertification were different from those of the other soil elements. TP decreased from form Community 1 to Community 5, while the AP concentration did not change in mid-level desertification (Community 3), but increased with serious desertification (Community 5).

Background/Objectives: Dental crowding and the premature loss of one or more deciduous teeth are common issues during the growth phase that accompanies the transition from mixed to permanent dentition. The aim of this systematic review is to examine the effectiveness of using a passive lingual arch in preserving the length of the lower arch and managing the leeway space, analyzing the effects on the linear and angular positions of the permanent teeth. Methods: A systematic review of the literature was conducted using the PubMed, Web of Science, Scopus, and Cochrane Library database. After an initial selection of 306 articles, seven studies that met the defined selection criteria were included. These articles were used to compile the PICO table. Results: The studies examined agree that the application of the passive lingual arch is useful in preserving the length of the lower arch during the transition from mixed to permanent dentition. The observed changes in the linear and angular positions of the permanent teeth, particularly the distoinclination of the permanent molars and the proclination of the incisors, were considered indicative of the effectiveness of this technique. However, one author did not observe these changes, noting only a prevention of mesioinclination and lingualization of the molars and incisors. Conclusions: The use of the passive lingual arch in the transition from mixed to permanent dentition proves to be advantageous for correcting mild anterior crowding, maintaining residual spaces after the premature loss of deciduous molars, and preventing the impaction of permanent premolars. This simple and effective orthodontic device can be applied in clinical practice, always based on an accurate diagnosis and a well-defined treatment plan.

This chapter presents some of the latest progress in terahertz (THz), infrared, and optical reflectarray antennas. Most reflectarray antenna research in the recent years has been in the microwave and sub‐millimeter range, and while microwave concepts can generally be extended to higher frequencies, several factors come into play that complicate the antenna design. The chapter discusses some basic material characteristics and design challenges, and then reviews several THz, infrared, and optical reflectarray antennas that have been developed over the years. The region of frequency spectrum between microwave frequencies and visible light consists of THz and infrared bands. At microwave frequencies, since a high conductivity is obtained for conductors and a low‐loss tangent can be achieved for substrates, the gain loss of a reflectarray due to the materials is relatively small. In traditional reflectarray antennas, both conductors and dielectrics are used in element designs.

Potassium leakage and morphological changes during imbibition of white spruce [Picea glauca (Moench) Voss] seeds and somatic embryos were investigated. A single desiccated somatic embryo, a single somatic embryo exposed to a high relative humidity environment for 2 d, and a single dry zygotic embryo leaked similar amounts of potassium over a 120-min period of imbibition in liquid germination medium. A seed without a seed coat leaked two and eight times more potassium than a single whole seed and a single zygotic embryo, respectively. Nearly 50% of the potassium leaked for all tissues was leaked within the first 20 min of imbibition. Exposure of somatic embryos to an environment with high relative humidity resulted in a reduction in the percentage of potassium leaked after 80 and 120 min to levels equivalent to those for zygotic embryos. Using an environmental scanning electron microscope, we found that desiccated somatic embryos and dry zygotic embryos had wrinkled surface cells, with cells in the surface of zygotic embryos being more shrunken in appearance. Imbibition of both types of embryos in water resulted in turgid surface cells after 2 h. Imbibition in liquid germination medium did not cause much hydration of surface cells, which still had wrinkled appearances after 2 h. Finally, imbibition on filter paper on semisolidified germination medium resulted in slower hydration of somatic and zygotic embryos. Cells near the medium appeared hydrated while cotyledon surface cells furthest from the medium resembled cells in desiccated embryos.

This chapter contains sections titled: Introduction Analytical Methods Atomic Absorption and Emission Spectrometry (AAS/AES) Techniques (Instrumental) Neutron Activation Analysis ((I)NAA) X‐Ray Techniques Electrochemical Techniques Techniques for Organometal Determinations Quality Assurance Summary Abbreviations References