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We report an ultra-shallow p-type doping of silicon resulting from the rapid thermal annealing of thin Al2O3 films deposited on intrinsic silicon with a native SiO2 layer, using a common atomic layer deposition process. Characterization revealed a two-stage decrease in sheet resistance, providing insights into the doping mechanism. [ABSTRACT FROM AUTHOR]

Silicon (Si) application may affect the plant response to nitrogen (N), possibly by changing the uptake, concentration, and partitioning of nutrients in plant tissues; however, this has not yet been proven in Arabica coffee plants. The effects of Si application methods [no Si, soil-applied soluble Si (168 mg Si L−1), and foliar-applied soluble Si (two application of 2 mg Si plant−1)] and N levels (0 and 80 mg N L−1) on biomass production and partitioning and uptake, partitioning, and stoichiometry of nutrients and Si in young Arabica coffee plants grown under greenhouse conditions were evaluated. Nitrogen fertilization increased the biomass production and uptake of all nutrients; however, reduced the concentrations of K, Ca, Mg, S, Mn, and Si in the leaves, Si in the stems, and K, Mg, and S in the roots of coffee plants as a dilution effect. In the presence of N, soil-applied Si increased the concentrations of Zn in the leaves and Ca and Si in the stems, the uptake of K, S, and Si, and the Si:N ratio. Foliar-applied Si increased the concentrations of N, P, K, and Zn in the leaves and Ca and Si in the stems, as well as the total uptake of K and Si and the Si:N ratio in coffee plants, being more evident in the N fertilization presence. This study unraveled that, especially when it was soil-applied, Si altered the nutrient uptake, allocation, and stoichiometric ratios with N, with a consequent increase in biomass production of young coffee plants fertilized with N. [ABSTRACT FROM AUTHOR]

The soil microbiome plays a pivotal role in the functioning and resilience of agricultural ecosystems, contributing to critical processes such as organic matter decomposition, nutrient cycling, and plant growth promotion. However, the soil microbiome is constantly challenged by various environmental stresses, including drought, heavy metal contamination, salinity, and climate change, which can significantly disrupt the delicate balance of the soil ecosystem. In this context, the application of silicon (Si) has emerged as a promising strategy to mitigate the adverse effects of these environmental stresses on the soil microbiome. This review paper synthesizes the current understanding of the impacts of environmental stresses on the soil microbiome and explores the potential of Si as a mitigating agent in enhancing the resilience of the soil microbial community. Silicon can enhance the resilience of the soil microbiome through several mechanisms, such as increasing soil pH, improving nutrient and water availability and uptake, altering root exudation patterns and plant physiology, and directly stimulating the abundance, diversity, and functional potential of key microbial groups. By enhancing the resilience of the soil microbiome, Si application can help maintain the critical ecosystem services provided by soil microorganisms, ultimately contributing to the sustainability and productivity of agricultural systems. The review also highlights future research aspects, including elucidating the precise mechanisms of Si-microbiome interactions, evaluating the long-term effects of Si on soil microbiome resilience, optimizing Si application strategies for specific crop-soil systems, integrating Si management with other sustainable soil practices, and assessing the impacts of Si on soil microbiome-mediated ecosystem services. [ABSTRACT FROM AUTHOR]

Feedback field-effect transistors (FBFETs) have been studied to obtain near-zero subthreshold swings at 300 K with a high on/off current ratio ~1010. However, their structural complexity, such as an epitaxy process after an etch process for a Si channel with a thickness of several nanometers, has limited broader research. We demonstrated a FBFET using in-plane WSe2 p−n homojunction. The WSe2 FBFET exhibited a minimum subthreshold swing of 153 mV/dec with 30 nm gate dielectric. Our modeling-based projection indicates that the swing of this device can be reduced to 14 mV/dec with 1 nm EOT. Also, the gain of the inverter using the WSe2 FBFET can be improved by up to 1.53 times compared to a silicon CMOS inverter, and power consumption can be reduced by up to 11.9%. [ABSTRACT FROM AUTHOR]

The mechanism of single-charge pumping using a dynamic quantum dot needs to be precisely understood for high-accuracy and universal operation toward applications to quantum current standards and quantum information devices. The type of charge carrier (electron or hole) is an important factor for determining the pumping accuracy, but it has been so far compared just using different devices that could have different potential landscapes. Here, we report measurements of a silicon ambipolar single-charge pump. It allows a comparison between the single-electron and single-hole pumps that share the entrance tunnel barrier, which is a critical part of the pumping operation. By changing the frequency and temperature, we reveal that the entrance barrier has a better energy selectivity in the single-hole pumping, leading to a pumping error rate better than that in the single-electron pumping up to 400 MHz. This result implies that the heavy effective mass of holes is related to the superior characteristics in the single-hole pumping, which would be an important finding for stably realizing accurate single-charge pumping operation. [ABSTRACT FROM AUTHOR]

Hybrid metasurfaces incorporated by active materials hold great promise for state‐of‐the‐art terahertz functional devices. However, it is still a major challenge to achieve ultrafast, dynamic, and multifunctional effective control of THz waves via hybrid metasurfaces. Herein, a modulator consisting of split rings and cut‐wires is first demonstrated, with an amplitude of −35.6 dB at 0.524 THz. By embedding semiconductor silicon into specified locations to form a hybrid metasurface, the ultrastrong connectivity of the silicon bridges leads to rapid optical molecularization. Under photoexcitation, the frequency tuning range is 26.7%, the phase shifting reaches 357.5°, and the maximal modulation depth is 94.54%. Taking advantage of the rapid relaxation of photocarriers in the silicon bridges, the ultrafast frequency switching is within 1400 ps. More interestingly, by changing the positions of the silicon bridges, the frequency tuning range is further promoted to 60%, the phase shifting is 353.5°, the modulation depth of 100% is achieved, and the full recovery time is 1600 ps. Furthermore, the underlying mechanism of the ultrafast tuning process is elucidated. This work demonstrates the feasibility of all‐optical‐controlled hybrid metasurface to achieve multifunctional dynamic modulation of THz waves, which has tremendous potential for applications in optical switching, signal processing, and frequency conversion. [ABSTRACT FROM AUTHOR]

Nearly four decades have passed since IBM scientists pioneered atomic force microscopy (AFM) by merging the principles of a scanning tunneling microscope with the features of a stylus profilometer. Today, electrical AFM modes are an indispensable asset within the semiconductor and nanotechnology industries, enabling the characterization and manipulation of electrical properties at the nanoscale. However, electrical AFM measurements suffer from reproducibility issues caused, for example, by surface contaminations, Joule heating, and hard‐to‐minimize tip drift and tilt. Using as experimental system nanoscale Schottky diodes assembled on oxide‐free silicon crystals of precisely defined surface chemistry, it is revealed that voltage‐dependent adhesion forces lead to significant rotation of the AFM platinum tip. The electrostatics‐driven tip rotation causes a strain gradient on the silicon surface, which induces a flexoelectric reverse bias term. This directional flexoelectric internal‐bias term adds to the external (instrumental) bias, causing both an increased diode leakage as well as a shift of the diode knee voltage to larger forward biases. These findings will aid the design and characterization of silicon‐based devices, especially those that are deliberately operated under large strain or shear, such as in emerging energy harvesting technologies including Schottky‐based triboelectric nanogenerators (TENGs). [ABSTRACT FROM AUTHOR]

Strain is commonly used in metal–oxide–semiconductor technologies to boost on‐state performance. This booster has been in production for at least a decade. Despite this, a systematic study of the impact of strain on off‐state leakage current has been lacking. Herein, experimental data and ab initio calculations are used to refine existing models to account for the impact of strain on band‐to‐band tunneling and trap‐assisted tunneling in silicon. It is observed that the strain may dramatically increase the leakage current, depending on the type of tunneling involved. For band‐to‐band and trap‐assisted tunneling, low uniaxial strains of 0.1% (or 180 MPa) can increase the leakage current by 60% and 10% compared to the unstrained case, respectively. Using models, it is predicted that compressive strain on the order of 1% (or 2 GPa) can increase the leakage current by 150 times. Conversely, tensile strain may diminish or at most double the leakage current in all observed cases. Though detrimental in conventional inversion‐mode metal‐oxide‐semiconductor field‐effect‐transistor, these processes may be used to boost the performance of tunnel field‐effect transistors, where on‐state current is defined by band‐to‐band tunneling. [ABSTRACT FROM AUTHOR]

A chemo- and regioselective hydroarylation of vinylsilanes with (hetero)aryl iodides under Ni–H catalysis is reported. This mild and straightforward protocol furnishes the anti-Markovnikov products in good yields as single regioisomers. This study demonstrates excellent control over the chemoselectivity and complements existing methods for the construction of homobenzylic silanes. [ABSTRACT FROM AUTHOR]

Silicon (Si) is a versatile nutrient that plays an instrumental role in mitigating biotic and abiotic stresses besides improving growth and yield of graminaceous crops. We hypothesized that application Si would significantly improve productivity and resilience of wheat. Hence, the objectives were a) to assess the impact of Si application on wheat growth, productivity, nutrient uptake, water use efficiency, and b) to determine the potentiality of Si in mitigating lodging and aphid density. Therefore, we conducted a field experiment with five levels of Si (0, 2, 4, 6, and 8 g Si liter−1) at three growth stages (crown root initiation, tillering, and jointing stage) using a factorial randomized block design replicated three times. The results showed that increasing Si doses positively influenced plant height, dry matter accumulation (DMA), leaf area index (LAI), yield, and nutrient uptake. The highest grain and straw yield were observed with 8 g Si liter−1, followed by 6 g Si liter−1, while the control had the lowest yields. With 8 g Si liter−1, grain yield, straw yield, and Si uptake increased by 10.5%, 13.5%, and 26.3%, respectively, compared to the control. Additionally, Si application at 8 g Si liter−1 significantly reduced the density of S. avenae (aphids) by 81.4% and lodging by 75.1% compared to the control. Overall, the study demonstrated that increasing Si doses enhanced various growth and yield parameters, with 8 g Si liter−1 and 6 g Si liter−1 showing superior results. Among the growth stages, foliar application of Si during the tillering stage exhibited better performance in terms of growth, yield, and nutrient uptake in wheat. Therefore, the study concludes that Si fertilization at a rate of 8 g Si liter−1 during the tillering stage can effectively improve growth, productivity, and nutrient uptake in wheat in the southern region of Rajasthan. [ABSTRACT FROM AUTHOR]

Silicon (Si) anode is of considerable interest in Li‐ion batteries due to its high theoretical capacity (4200 mAh g−1), abundant reserves in the earth, and environmentally friendly nature. Although Si anode has significant advantages, the electrode is prone to cracks due to large volume changes in its structure during discharge cycles in Li‐ion batteries. Rapid capacity degradation occurs as a result of deterioration of the structural integrity of the electrode. Although binders are known to contribute to improving the electrochemical performance of anode materials, polyvinylidene fluoride (PVdF) used in commercial Li‐ion batteries cannot maintain the mechanical stability of the Si anode during cycles due to weak Van der Waals interactions, which also dissolves in the flammable, explosive and volatile solvent N‐Methyl‐2‐pyrrolidone (NMP). In this study, low cost, sustainable and environmentally green psyllium gum (PG) was extracted from psyllium husk and tested for the first time as a water‐soluble binder for Si anode. According to galvanostatic charge/discharge tests, the Si‐PG anode exhibits a capacity of 1415 mAh g−1 after 100 cycles at a voltage range of 0.01–1.5 V and current density of C/2, which is almost 3 times higher than the Si‐PVdF anode (494 mAh g−1). [ABSTRACT FROM AUTHOR]

Silicon, carbon and oxygen hybrid nanomaterials (i.e., SiCOHNs) have recently drawn extensive attention as versatile photoluminescence (PL) nanosystems. The collective advantages of silicon‐ and carbon‐based nanostructures have resulted in SiCOHNs with tunable and photostable PL properties, abundant possibilities for surface modification, and low biotoxicity. Although SiCOHNs have shown great potential in diverse applications, such as bioimaging, biosensing, drug delivery and information encryption, discovering novel SiCOHNs with explicit nanostructures and elucidating the fundamental mechanisms of their PL properties for bioapplications are highly desirable. In this review, on the preparation of SiCOHNs on the basis of the synthesis conditions and precursors are first focused. Next, the manipulation of the emission wavelength, quantum yield and RTP of SiCOHNs is discussed. On the basis of previous reports and the recent experimental/theoretical results, the primary structure of SiCOHNs is clarified and deduced their possible PL mechanism. SiCOHNs possess bacterial uptake efficiency and/or anticancer capacity, promoting various biomedical applications and proof‐of‐concept applications in anti‐counterfeiting. Finally, current challenges and future trends are summarized as a roadmap for the development of SiCOHNs‐based optical applications. [ABSTRACT FROM AUTHOR]

In this paper, the dissolution behavior of crystal-originated particle (COP) in 300 mm Czochralski silicon under argon annealing was investigated. The latex sphere equivalent size distributions of defects along the depth direction in silicon wafers annealed under different conditions were quantified utilizing chemical–mechanical polishing and localized light scattering inspection. The interstitial oxygen concentration profiles were quantified by secondary ion mass spectrometry, and the distributions of oxygen precipitation within annealed wafers were obtained based on peak analysis. Furthermore, the classical theoretical model was employed to elucidate the depth-dependent dissolution of COP. Based on the initial COP sizes and oxygen concentrations, the relationship between COP sizes and depth after annealing was calculated. The depth distributions of defects obtained by combining the dissolution of COP from calculation with the changes of oxygen precipitation were found to be highly consistent with the measurement results. These findings could enhance the understanding of the mechanism of COP dissolution, which contributes to the production of defect-free silicon wafers for nanometre-scale integrated circuits. [ABSTRACT FROM AUTHOR]

Photoelectron spectroscopy and theoretical calculations have identified the global minimum structure of the 16‐valence electron Si3Cu3− cluster, which features a planar tetracoordinate silicon (ptSi) in a rhombic arrangement. The Si3 and Cu3 triangles are interconnected by a Si2/Cu2 edge, forming an ordered chain‐like structure. Besides the conventional 2c–2e σ‐bond connecting Si3 and Cu3, the stability of this cluster is reinforced by a delocalized 3c–2e σ‐bond in Cu3 and a π‐bond in Si3. Our study provides experimental confirmation of a planar hypercoordinate heavier Group 14 element, opening possibilities for exploring similar structures in two‐dimensional materials. [ABSTRACT FROM AUTHOR]

Background and aims: Rhizosheath, a mixture of soil and mucilage that remains attached to the root system after being removed from the soil and shaken, plays a prominent role in the resistance of plants to drought stress. This study aims to investigate the effect of silicon (Si) on rhizosheath formation and mitigate the effects of drought stress in wheat. It was hypothesized that Si positively enhances root hair formation and rhizosheath formation under soil drying conditions, improving plant access to water under soil drying conditions. Methods: Wheat seeds were grown under different levels of Si (control, 150 and 300 mg kg−1 monosilicic acid, and 150 and 300 mg kg−1 nano-silicon) and irrigation (0.4 field capacity (FC) and 0.8 FC) under greenhouse conditions. Results: Under drought stress, the application of Si significantly increased root hair length, density, rhizosheath formation, and transpiration rate. Applying Si increased the length of root hairs by 45–107% and their density by 25–78%. Under drought stress, application of 150 and 300 mg kg−1 of monosilicic acid and nano-silicon increased rhizosheath formation by 40.3, 48.2, 16.8, and 17.5%, and transpiration rate by 17.8, 36.4, 11.4, and 29.1%, respectively. Si also increased superoxide dismutase and catalase activity, while decreasing malondialdehyde and hydrogen peroxide content. Conclusion: Silicon application in drought-stricken wheat improved water uptake, leading to improved plant water relations and other morpho-physiological and biochemical responses. This was achieved by modifying root system traits, particularly increasing root hair length and density, which facilitated the formation of rhizosheath. [ABSTRACT FROM AUTHOR]

Zoysia japonica Steud. (zoysia grass), with its high drought, shade, and salt tolerance, it is an excellent choice for green areas. However, in regions with subtropical climates, it goes into winter dormancy with a loss of green color and functionality, which is a main barrier to its widespread use. The application of silicon and nitrogen in fall was hypothesized to enhance winter color retention of Z. japonica. This study assessed the impact of fall (late-season) nitrogen (0, 2.5, or 5.0 g/m2 ammonium sulfate) and foliar silicon (0, 3, or 6 mL/L potassium silicate) applications on the winter color retention of Z. japonica grown in the field. The experiment was conducted over two consecutive growing seasons in Antalya, Türkiye. Turfgrass quality, color, chlorophyll content, shoot density, and winter dormancy were all improved by late-season nitrogen application. Overall, two sequential nitrogen applications at 5 g/m2 in fall provided 65% to 100% green coverage with acceptable turfgrass quality during fall and winter, indicating the possibility of maintaining the year-round green color of Z. japonica in subtropical climates. However, the silicon treatment did not affect the winter color retention of Z. japonica. The apparent lack of a beneficial response of Z. japonica to the silicon application might be due to the dose, application methods, and silicon source. [ABSTRACT FROM AUTHOR]

As the negative electrode material of lithium-ion battery, silicon will produce huge volume expansion when it is removed/embedded in lithium, so that it will pulverize itself, resulting in rapid capacity decay. Existing studies have shown that Si nanocrystallization and alloying can alleviate the crushing effect caused by volume deformation. In order to efficiently prepare nano-sized Si-Sn powder materials, plasma arc was used as a heat source to nano-size Si, and then nano-alloying of Si-Sn powder materials was realized by plasma arc. The effects of plasma current on the preparation characteristics of Si and Si-Sn nano-powder materials were studied. The prepared phase was detected by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of silicon nanowires as anode materials were detected by battery test system and electrochemical workstation. The results show that the use of plasma arc can achieve efficient preparation of silicon nanowires, and the addition of low melting point Sn is beneficial to the homogenization of the diameter scale of silicon nanowires. The efficiency of the two groups of silicon nanowires can be maintained at about 90% after the third charge-discharge cycle. The addition of Sn can further improve the conductivity and stability of the silicon anode. After 60 cycles, the specific capacity of the battery is 117.5 mAh/g. [ABSTRACT FROM AUTHOR]

Here, a high-sensitivity silver-based surface plasmon resonance biosensor by a coating of zinc oxide on silicon for detecting hybridization of DNA is reported numerically. By changing the surface plasmon resonance angle and the minimum reflectance, this proposed biosensor can examine the difference between matched and mismatched DNA strands, as well as the nucleotide bonding between double-stranded (dsDNA) helix structures, and recognize the hybridization of target DNAs by using probe DNA immobilized on zinc oxide in the proper orientation. Also, the methodology of this work can detect single nucleotide polymorphisms (SNP). Using the transfer matrix method, we investigated the performance parameters of the biosensor. We observed that our proposed sensor has a maximum sensitivity of 378.36 deg/RIU and a good quality factor of 71.183 RIU−1. As we can see, compared with other reported papers, our proposed biosensor shows much better performance. This paper uses the biocompatibility, the electrical properties, the chemical stability, and high affinity of both Si and ZnO in surface plasmon resonance biosensors for the hybridization of DNA. [ABSTRACT FROM AUTHOR]

The surface plasmon resonance (SPR) sensor with better sensitivity and gas detection capabilities is reported in this paper. It is based on a hybrid layer of silver (Ag)/magnesium oxide (MgO)/silicon (Si). For numerical analysis, the finite element technique (FEM) was employed. The attenuated total reflection (ATR) approach has been used for diagnosing various types of hazardous gas. The increase in the refractive index of various hazardous gases, ranging from 1.327 to 1.38 for four different types of gas, caused the resonance angle to shift. The obtained sensitivities were 86.12 deg/RIU, 164.54 deg/RIU, 199.59 deg/RIU, and 253.68 deg/RIU, respectively, for cyanogen, phosgene, ethanol, and propane gas. Additionally, the values of the detection accuracy (DA), the figure of merits (FoM), and full-width at half-maximum (FWHM), which are 0.17 deg−1, 43.30 RIU−1, and 5.86 deg, respectively, were also obtained. The proposed structure's distribution of the electric field propagation under resonant conditions was also depicted. Further tests were done to see how the thickness of the Ag and other layers affected the overall sensitivity sensor for the four different gas types. The proposed layered Ag/MgO/Si arrangement had the highest overall sensitivity in distinguishing propane gas from other hazardous gases. [ABSTRACT FROM AUTHOR]

The performance of herbivorous animals depends on the nutritional and defensive traits of the plants they consume. The uptake and deposition of biogenic silicon in plant tissues is arguably the most basic and ubiquitous anti‐herbivore defence used by plants, especially grasses. We conducted meta‐analyses of 150 studies reporting how vertebrate and invertebrate herbivores performed when feeding on silicon‐rich plants relative to those feeding on low‐silicon plants. Silicon levels were 52% higher and 32% more variable in silicon‐rich plants compared to plants with low silicon, which resulted in an overall 33% decline in herbivore performance. Fluid‐feeding herbivore performance was less adversely impacted (−14%) than tissue‐chewing herbivores, including mammals (−45%), chewing arthropods (−33%) and plant‐boring arthropods (−39%). Fluid‐feeding arthropods with a wide diet breadth or those feeding on perennial plant species were mostly unaffected by silicon defences. Unlike many other plant defences, where diet specialisation often helps herbivores overcome their effects, silicon negatively impacts chewing herbivores regardless of diet breadth. We conclude that silicon defences primarily target chewing herbivores and impact vertebrate and invertebrate herbivores to a similar degree. [ABSTRACT FROM AUTHOR]

An instrumentation amplifier (IA), aimed at wideband bioimpedance analysis in the low‐voltage low‐power scenario of internet of medical things (IoMT), is presented. The operation principle is based on the indirect current feedback technique, where an input and a feedback transconductor determine the voltage gain of the preamplifier. The required transconductors consist of two bulk‐driven flipped‐voltage‐follower cells and an active pseudo‐resistor, thus leading to a linear and compact implementation. The circuit has been designed and fabricated in 180 nm CMOS technology to operate with a 0.6‐V supply. Experimental results obtained from measurements on eight samples of the silicon prototype show that when the IA is programmed to have a nominal voltage gain of 11 V/V, the bandwidth is 316.2 kHz, the CMRR exceeds 63 dB, and the maximum output voltage that can be processed with a THD below –40 dB is 555 mV pp. [ABSTRACT FROM AUTHOR]

The conventional methods of silicon stent insertion recommend usage of external loading devices, where the stent is folded into the loading device and pushed in to the tracheobronchial tree using an external pusher which is blind, and leads to placement of stent either distally or proximally needing repositioning or is done with fluoroscopy that involves radiation exposure. We demonstrate our experience in 16 cases of successful silicon stent placement using this technique, wherein an Ultrathin flexible bronchoscope or Hopkins Rigid telescope is pushed alongside the forceps that hold upper end of the folded silicon stent allowing stent placement under direct vision with control over the stent. The Proximal end of the stent can be pulled under vision before deployment for appropriate positioning while pulling the rigid barrel. The stent is always under the operator's control providing excellent control over placement, simplifies the procedure and is safe with no reported complications. [ABSTRACT FROM AUTHOR]

Femtosecond-laser-fabricated black silicon has been widely used in the fields of solar cells, photodetectors, semiconductor devices, optical coatings, and quantum computing. However, the responsive spectral range limits its application in the near- to mid-infrared wavelengths. To further increase the optical responsivity in longer wavelengths, in this work, silicon (Si) was co-hyperdoped with nitrogen (N) and selenium (Se) through the deposition of Se films on Si followed by femtosecond (fs)-laser irradiation in an atmosphere of NF3. The optical and crystalline properties of the Si:N/Se were found to be influenced by the precursor Se film and laser fluence. The resulting photodetector, a product of this innovative approach, exhibited an impressive responsivity of 24.8 A/W at 840 nm and 19.8 A/W at 1060 nm, surpassing photodetectors made from Si:N, Si:S, and Si:S/Se (the latter two fabricated in SF6). These findings underscore the co-hyperdoping method's potential in significantly improving optoelectronic device performance. [ABSTRACT FROM AUTHOR]

A multi‐technique analysis was used to investigate how the orientation of single‐crystal Si wafer surfaces affects the size, shape and orientation of NiSi2 nanocrystals grown within the wafers through the thermal diffusion of Ni atoms from a nickel‐doped thin film deposited on the surface. Nickel‐doped thin films were prepared on silicon wafers with three distinct crystallographic orientations, [001], [110] and [111]. Three sets of samples were then annealed at 500, 600 and 700°C for 2 h. Regardless of crystallographic orientation or annealing temperature, NiSi2 nanoplates with a nearly hexagonal shape grew close to the external surface of the wafers, aligning their larger surfaces parallel to one of the planes of the Si{111} crystallographic form. The crystallographic orientation and annealing temperature in the 500–700°C range did not significantly affect the final values of the average diameter and thickness of the nanoplates. However, significant differences were noted in the number of nanoplates formed in Si wafers with different crystallographic orientations. The results indicate that these observed differences are correlated with the number of pre‐existing defects in the wafers that influence the heterogeneous nucleation process. In addition, the average size and size dispersion were determined for pores at the surface of the Si wafers formed due to the etching process used for native oxide removal. [ABSTRACT FROM AUTHOR]

Silicon significantly affects the microstructure and properties of wear-resistant alloys. To investigate the effect of silicon content on the microstructure and properties of high-vanadium wear-resistant alloys (HVWA), three alloys with different silicon content (HVWA-0.66Si, HVWA-2.14Si and HVWA-5.17Si) were formulated and synthesized. And the solidification structure and wear behavior of HVWAs were researched. The increased content of silicon enhances the precipitation temperature of VC and therefore promotes the formation of more pellet/agglomerate primary VC in solidification and decreases the content of strip eutectic VC. The as-cast structure of HVWAs comprises of pearlite, with numerous submicron carbides dispersed on the pearlite matrix. The increased content of silicon increases the lamellar spacing of pearlite and the particle size of submicron carbides. The lamellar spacing of pearlite in HVWA-0.66Si, HVWA-2.14Si and HVWA-5.17Si measures 50–300 nm, 200–600 nm and 300–1800 nm, correspondingly, while the size of the submicron carbides is 0.3–0.9 μm, 0.5–1.3 μm and 0.3–1.9 μm, accordingly. The impact toughness of the alloy reduces as the silicon content increases. The HVWA-5.17Si matrix has a hardness of 49.3 HRC and boasts exceptional wear resistance. Taking HVWA-0.66Si as a reference, the relative wear resistance ε of HVWA-5.17Si has the highest wear resistance, with ε reaching 1.75. The strong wear resistance of HVWA-5.17Si stems mainly from the solid solution of silicon in the matrix that heightens its hardness. This feature works in tandem with the high-hardness primary VC and an abundance of finely formed secondary vanadium carbides that precipitate in the as-cast alloy. [ABSTRACT FROM AUTHOR]

The near-eutectic aluminum–nickel alloys are promising to be used for thermal management purpose because of their excellent thermal conductivity. However, owing to the solid solubility of nickel in aluminum lattice is small, the mechanical properties of these alloys can barely be promoted via the solid solution strengthening effect. The present study investigates the trace addition of silicon on the microstructure, rheology property, mechanical performance and thermal conductivity of the Al–5Ni alloy. Results show that the α-Al grains in the Al–5Ni alloy with trace silicon are significantly refined, and the fibrous Al3Ni phase is notably modified. It leads to a remarkable improvement of its mechanical properties. However, the mechanical properties and thermal conductivity are prominently decreased when the dosage of silicon excesses 0.3 wt%. The molten Al–5Ni alloy with relatively high silicon content possesses wider temperature range for flowing, indicating a sound fluidity of the melts, which is related to the solidification routes of the samples. This work provides a reference for the design of cast aluminum alloys with high strength and excellent thermal conductivity. [ABSTRACT FROM AUTHOR]

Key message: Promoters of moso bamboo silicon transporter genes PeLsi1-1 and PeLsi1-2 contain elements in response to hormone, silicon, and abiotic stresses, and can drive the expression of PeLsi1-1 and PeLsi1-2 in transgene Arabidopsis. Low silicon 1 (Lsi1) transporters from different species have been shown to play an important role in influxing silicon from soil. In previous study, we cloned PeLsi1-1 and PeLsi1-2 from Phyllostachys edulis and verified that PeLsi1-1 and PeLsi1-2 have silicon uptake ability. Furthermore, in this study, the promoters of PeLsi1-1(1910 bp) and PeLsi1-2(1922 bp) were cloned. Deletion analysis identified the key regions of the PeLsi1-1 and PeLsi1-2 promoters in response to hormone, silicon, and abiotic stresses. RT-qPCR analysis indicated that PeLsi1-1 and PeLsi1-2 were regulated by hormones, salt stress and osmotic stress. In addition, we found that the driving activity of the PeLsi1-1 and PeLsi1-2 promoters was regulated by 2 mM K2SiO3 and PeLsi1-1-P3 ~ P4 and PeLsi1-2-P4 ~ 5 were the regions regulated by silicon. Overexpression of PeLsi1-1 or PeLsi1-2 driven by 35S promoter in Arabidopsis resulted in a threefold increase of Si accumulation, whereas transgenic plants showed deleterious symptoms and dwarf seedlings and shorter roots under 2 mM Si treatment. When the 35S promoter was replaced by PeLsi1-1 or PeLsi1-2 promoter, a similar Si absorption was achieved and the transgene plants grew normally. This study, therefore, demonstrates that the promoters of PeLsi1-1 and PeLsi1-2 are indeed effective in driving the expression of moso bamboo Lsi1 genes and leading to silicon uptake. [ABSTRACT FROM AUTHOR]

The synthesis of silanes starting from multifunctionalized precursors often suffers from low chemoselectivity due to the similar kinetic reaction profiles, leading to the formation of difficult to separate side products. The opposite approach, which is an access based on unreactive tetraalkylsilanes as starting materials, is far less developed. Making use of the silylium-ion-initiated chemoselective halodealkylation of tetraalkylsilanes recently developed by our laboratory, an extension of this protocol, namely the direct synthesis of dihalosilanes from tetraalkylsilanes, is reported. Following a sequence of halodehydrogenation and halodealkylation, trialkylhydrosilanes can also be converted into dihalosilanes. Commercially available 1,2-dihaloethane acts as the halogen source and is involved in the generation of the catalytically active arenium ion by an SE Ar substitution of the benzene solvent. The formation of an uncommon halogen-substituted silylium ion as an intermediate is assumed, likely accounting for the need of an elevated reaction temperature. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) modules are a key technology to aid the imminent transition from carbon‐based energy. End‐of‐life crystalline silicon PV modules produce a waste stream that is predominantly landfilled due to the recycling challenges associated with PV reuse economics. Current practices recycle the aluminum frame and repurpose the junction box but landfill the rest of the module. The primary challenge in recycling the remaining module is finding a technoeconomically viable method for separating the silicon and glass from the ethylene vinyl acetate (EVA) layers. This issue will rapidly expand with time as it is estimated that flat glass production for solar panels is currently unable to meet the demand for PV. Current literature suggests that chemical, thermal, and mechanical delamination offer economically feasible solutions under ideal circumstances. In this work we evaluate these methods using end‐of‐life panels and assess the economic viability. The technoeconomic study presented here suggests the most economically viable option for disposing of end‐of‐life solar panels, given current technology, is landfilling. Thermal delamination may offer an alternative route in the future. Financial incentives, which can be quantified with this work, may be required to kickstart PV recycling to help bridge externalities around environmental impact. [ABSTRACT FROM AUTHOR]

In this work, silicon microcrystals doped with a boron impurity to concentrations corresponding to the metal-dielectric transition in silicon of 5.5·1018 cm−3 and a nickel impurity in the temperature range of 4.2 ÷ 70 K under alternating current in the frequency range of 0.010 ÷ 250 kHz were studied. The features of the frequency response of silicon microcrystals are determined. On the basis of Nyquist diagrams, an equivalent conductivity scheme at low temperatures is proposed. The frequency response of the samples was evaluated and the mechanisms of charge carrier flow were proposed depending on the observation conditions. Conduction mechanisms from quantum mechanical tunneling (QMT) to superlinear power law (SLPL), which can be implemented in crystals, are considered. [ABSTRACT FROM AUTHOR]

The inevitable residual carbon that normally appears in the polycarbosilane-derived SiC ceramics has notorious effects on the crystallinity and thermal conductivity of SiC ceramic. In this study, nano Si was employed to fully exhaust unwanted residual carbon in a liquid polycarbosilane. Through addition of 12 wt% theoretical nano Si and pyrolysis to 1600 °C, the ceramic yield of the liquid polycarbosilane increased from 72.0 wt% to 81.8 wt% and the C/Si ratio of ceramic product decreased from 1.14 to 0.99. Raman spectroscopy and transmission electron microscope also confirmed that the residual carbon almost completely disappeared. In addition, the crystallization ability of SiC also improved, and as a result dramatical improvement in the thermal conductivity of SiC f /SiC composite was achieved. The reaction mechanism was investigated in detail to understand the residual carbon trapping effect of nano Si during the precursor-to-ceramic conversion. [ABSTRACT FROM AUTHOR]

Metal(loid) pollution has become one of the most pressing environmental issues, threatening all living organisms. Metal(loid) stress adversely impacts plant growth, physiology, and overall productivity. Numerous physicochemical approaches have been developed and employed to counteract and reduce the detrimental effects of metal(loid)s. However, these methods have raised environmental concerns, leading to questions about their appropriateness and efficacy. Consequently, alternative and eco-friendly solutions, such as the application of biochar, have gained prominence. Biochar is a carbon-rich material derived from the pyrolysis and hydrothermal processes of various organic materials. Due to its exceptional physicochemical properties, biochar is believed to enhance soil quality and fertility. Several global studies have underscored the positive role of biochar in reducing the uptake of metal(loid)s by plants in polluted soils. In this article, we explore various facets of plant reactions to metal(loid)s toxicity and attempt to draw links between biochar use and improvements in plant physiology and performance. We also review the effectiveness of biochar in phytoremediation, its influence on nutrient adsorption mechanisms, and its role in assisting plant growth and defense systems. [ABSTRACT FROM AUTHOR]

To mitigate the transmission losses, glass vias have the potential to replace silicon vias in wireless transmission systems. In the wake of limitations of the existing methods, ECDM is an evolving process for glass micro drilling. However, the process control of ECDM is compromised due to variation in electrolytic conditions in terms of concentration and temperature. As a result, poor stability and sustainability hampers the commercial viability of the ECDM process. Therefore, present communication attempted to enhance the stability and sustainability of the ECDM with a novel approach and termed as controlled-ECDM. Subsequently, the process stability (real time based) of the controlled-ECDM has been compared with basic-ECDM using the user's preference rating and I-MR chart. The results indicated a 20.65% gain in overall stability by controlled-ECDM. Additionally, the assessment of electrolyte emissions and performance on the radar graph indicated an improvement in the sustainability of the process. [ABSTRACT FROM AUTHOR]

Three-dimensional integrated systems employing vertical stacking technology and through-silicon via (TSV) interconnects offer enhanced performance and reduced power consumption. However, TSV technology introduces elector-thermal coupling phenomena, compromising the reliability and efficiency of these systems. This study provides a comprehensive review of simulation design advancements for elector-thermal coupling in TSV-based three-dimensional integrated circuits. Electrical and thermal simulation methodologies are elucidated and potential impacts and mitigation strategies are thoroughly explored. A systematic analysis is presented to elucidate the challenges and optimization opportunities in elector-thermal coupling, informing future research directions. [ABSTRACT FROM AUTHOR]

The paper presents experimental study results of self-oscillations of the current of the recombination wave (RW) type in silicon doped with impurity selenium atoms. Doping of silicon with impurity selenium atoms was carried out using a newly developed technology, which allows for the formation of nanoclusters of impurity selenium atoms in the silicon lattice consisting of Se2 and Se4 molecules, without erosion of the surface of the samples. Self-oscillations in the samples were detected at room temperature and at sufficiently low electric fields. The dependences of the RW parameters (amplitude and frequency) in the Si samples on the resistivity and concentration of the formed nanoclusters of selenium atoms, as well as on the influence of a magnetic field, which makes it possible to control the amplitude in the range of J = 10–5–5 × 10–3 A and the frequency of self-oscillations of f = 104–(5 × 106) Hz. The mechanism of the observed RWs is explained by the formation of nanoclusters consisting of two (Se2) or four (Se4) selenium atoms in silicon, which leads to the formation of fluctuations (clusters) of the main charge carriers and their reaching contact when determining the magnitude of the applied constant electric field. A possibility of practical use of self-oscillations of current observed in silicon diffusion doped with selenium impurity atoms to create solid-state generators is shown. [ABSTRACT FROM AUTHOR]

We present the results of a self-consistent analysis of the magnetic silicon star BD+00°1659, based on its high-resolution spectra taken from the ESPaDOnS archive (R = 68,000). This narrow-lined star shows the typical high Si abundance and Si ii– iii anomaly, making it an ideal prototype for investigating the vertical distribution of Si and Fe in the stellar atmosphere. The derived abundances, ranging from helium to lanthanides, confirm the star's classification as a silicon Bp spectral type. Silicon and iron are represented by lines of different ionisation stages (Fe i– iii, Si i– iii), indicating an ionisation imbalance interpreted as evidence of atmospheric stratification. Our stratification analysis reveals that there is a jump in iron and silicon abundances of 1.5 dex at atmospheric layers with an optical depth of log τ 5000 = −0.85–−1.00. Non-LTE calculations for iron in this stratified atmosphere show minor non-LTE effects. Our results can be applied to studying the impact of stratification on the emergent flux in rapidly rotating Si stars with similar atmospheric parameters and abundance anomalies (for example, MX TrA), where direct stratification analysis is challenging due to line blending. [ABSTRACT FROM AUTHOR]

Broken screw removal from the implant connection is a common but challenging process. Several proposed methods and technical solutions may result in unsuccessful removal; thus, a novel, more conservative, risk-free method is proposed as a first attempt. The proposal is to use a silicon restoration holder to be twisted counterclockwise on the dried surface of the broken fragment inside the implant connection. This method, within the limitations of a minimal case series, yielded 100% results; however, despite previous attempts with less conservative techniques, this approach showed no efficacy. This article aims to promote the use of silicon restoration holders as a minimally invasive first attempt at broken screw retrieval treatment before considering other options. [ABSTRACT FROM AUTHOR]

Recently, seed priming has gained significant attention as a technique to enhance stress tolerance in various crop plants. The current research investigated the alleviative effect of s eed p riming w ith s ilicon (Si, 2 m M Na2SiO3) on the early growth and antioxidant activity of fenugreek (Trigonella foenum-graecum L.), an aromatic and medicinal plant when exposed to zinc oxide nanoparticles (ZnO NPs) toxicity levels (0, 100, and 200 mg L-1). The findings revealed that ZnO NPs toxicity had a notable detrimental effect on growth-related factors. However, Si priming proved effective in attenuating oxidative stress, promoting growth, and increasing the levels of soluble metabolites (soluble carbohydrates, soluble proteins, and free amino acids) in the presence of ZnO NPs toxicity. Moreover, Si priming significantly enhanced both enzymatic and non-enzymatic plant antioxidants compared to non-primed plants under ZnO NPs stress. Therefore, the results of this study support the use of seed priming in Si which was mostly effective in improving the growth and physiological traits of fenugreek plants by alleviating the detrimental effects of ZnO NPs toxicity. [ABSTRACT FROM AUTHOR]

When two resonators of coupled silicon resonators are identical and the gain on one side is equal to the loss on the other side, a parity-time (PT) symmetric-coupled silicon resonator is formed. As non-Hermitian systems, the PT-symmetric systems have exhibited many special properties and interesting phenomena. This paper proposes the strain-induced frequency splitting in PT symmetry-coupled silicon resonators. The frequency splitting of the PT system caused by strain perturbations is derived and simulated. Theory and simulation both indicate that the PT system is more sensitive to strain perturbation near the exceptional point (EP) point. Then, a feedback circuit is designed to achieve the negative damping required for PT symmetry. Based on a simple silicon-on-insulator (SOI) process, the silicon resonator chip is successfully fabricated. After that, the PT-symmetric-coupled silicon resonators are successfully constructed, and the frequency splitting phenomenon caused by strain is observed experimentally. [ABSTRACT FROM AUTHOR]

To improve the performance of valves in relation to the leakage rate, a comprehensive evaluation of the valve characteristics and behavior during pressure exposure is important. Often, these low gas flow rates below 0.1 cm3/min cannot be accurately measured with conventional flow sensors. This paper presents a small and low-cost test rig for measuring gas leakage rates accurately, even far below 0.1 cm3/min, with the pressure decay method. These leakage flows are substantiated with a flow model, where we demonstrate the feasibility of modeling those gas flows with an extended Navier–Stokes framework to obtain more accurate theoretical predictions. As expected, the comparison to the experimental results proves that the classical Navier–Stokes system is unsuitable for modeling Knudsen flows. Hence, self-diffusion of gas, a wall-slip boundary condition, and an effective mean free path model were introduced in a physically evident manner. In terms of the calculated mass flow, while self-diffusion and slip boundary conditions explain deviations from the classical Navier–Stokes equation for Knudsen numbers already smaller than 1, the effective mean free path model has an effect, especially when Kn > 1. For simplified conditions, an analytical solution was presented and compared to the results of an OpenFOAM CFD-solver for flow rates through more complex gap-flow geometries of the flap valve. Hereby, acceptable deviations between 10% and 20% were observed. A comparison with measurement results was carried out. The reproducibility of the measurement method was verified by comparing multiple measurements of one silicon microvalve sample to a state-of-the-art flow sensor. Three geometrically similar passive silicon microvalves were measured with air overpressure decreasing from 15 kPa relative to atmospheric pressure. Maximum gas volume flowing in a blocking direction of 1–26 µL/min with high reproducibility and marginal noise were observed. [ABSTRACT FROM AUTHOR]

In this paper, a novel fabrication process for the realization of large, suspended microfluidic channels is presented. The method is based on Buried Channel Technology and uses a mixture of HF, HNO3, and water etchant, which has high selectivity between the silicon substrate and the silicon-rich silicon nitride mask material. Metal electrodes for actuation and read-out are integrated into the fabrication process. The microfluidic channels are released from the silicon substrate to allow the vibrational movement needed for the application. The resulting microfluidic channels have a near-circular cross-section, with a diameter up to 300 μm and a channel wall thickness of 1.5 μm. The structure of a micro-Coriolis mass-flow and density sensor is fabricated with this process as an example of a possible application. [ABSTRACT FROM AUTHOR]

In this article, we report a novel pressure sensing method based on the Hall effect and a hard magnet magnetorheological elastomer (hmMRE). The elastic property of the MRE under pressure was used to generate spatial variation in the magnetic flux density around the MRE, and the variation was detected by the Hall effect device underneath. As the first development in this kind of pressure sensing mechanism, we conducted research for the following three purposes: (1) to verify the Hall effect on the output signal, (2) to understand the sensor output variations under different modes of operation, and (3) to utilize the mechanism as a pressure sensor. We characterized the sensor with its operation parameters, such as signal polarity switching depending on wiring directions, signal amplitude, and offset shift depending on the input voltage. Based on the analyses, we concluded that the Hall voltage represents the pressure applied on the hmMRE, and the new pressure sensing mechanism was devised successfully. [ABSTRACT FROM AUTHOR]

The production of organic silicon (Si) monomer from metallurgical-grade silicon (MG–Si) is hindered by CaSi2, leading to a decreased yield of (CH3)2SiCl2. Therefore, strict control of CaSi2 content is essential. However, the existing MG–Si oxidation refining process fails to prevent the precipitation of FeSi2 and the reduction of Si8Al6Fe4Ca content, while simultaneously decreasing CaSi2 content. To address this issue, a novel method of adjusting aluminum (Al) content in MG–Si to reduce CaSi2 content and increase Si2Al2Ca or Si8Al6Fe4Ca content was proposed. The results indicated that the impurity ratio in MG–Si directly influenced the type of precipitating intermetallics. Specifically, when m(Al/Ca) < 1.35, CaSi2, FeSi2, and Si2Al2Ca were present. When 1.35 < m(Al/Ca) < 1.35 + 0.48 m(Fe/Ca), FeSi2, Si2Al2Ca, and Si8Al6Fe4Ca were encountered. Additionally, when the Al content m(Al/Ca) > 1.35 + 0.48 m(Fe/Ca), only Si2Al2Ca and Si8Al6Fe4Ca were observed. Upon adjusting the Al content in high-Ca MG–Si to m(Al/Ca) > 1.35, CaSi2 was effectively eliminated. Furthermore, within the experimental range, the average content of Si8Al6Fe4Ca precipitates increased from 12.84 to 37.94 wt pct after adjusting the Al content in the melt, representing a maximum increase of ~ 2.95 times. This study successfully elucidated the regulation of calcium (Ca)-containing intermetallics in high-Ca MG–Si, paving the way for the production of high-quality MG–Si raw materials for silicone monomer synthesis. [ABSTRACT FROM AUTHOR]

Silicon epitaxy is an essential building block in the manufacturing of complementary metal‐oxide semiconductor (CMOS) devices. Accurate determination of epitaxial layer thickness is indispensable for a uniform and reproducible process. In this paper, we compare thickness values of the transition zone (TZ) in silicon epitaxial wafers obtained by two of Semilab's production‐compatible electrical and optical characterization techniques: Fourier‐transform infrared (FTIR) reflectometry and spreading resistance profiling (SRP). We demonstrate a high correlation between TZ thicknesses obtained from the optical modeling of FTIR reflectance spectra and SRP profiles. The dependence of TZ thickness change on the high‐temperature annealing steps is also examined. FTIR reflectometry thus offers a quick, contactless alternative for obtaining structural parameters of an epitaxial layer, and these values can be well matched to those given by SRP. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the current era, a wide range of biotic and abiotic stresses are becoming more prevalent across the globe, which can limit the growth of plants, especially the prime crops. Silicon (Si) fertilizer is known as an ecologically compatible and biologically approachable technique for enhancing rice crop resilience to various stresses. This review comprehensively explores the standpoint of silica fertilizers focusing on their multifaceted roles in improving plant health, stress tolerance, optimizing rice productivity and sustainability. Silica, in the form silicic acid is actively absorbed by rice roots through transporters such as LSi1, LSi2, and LSi3 then transported within root cells via diffusion. This movement is essential for stress mitigation, as silicon deposition in various tissues forms a protective barrier against pest and diseases. In rice cultivation silica is crucial for enhancing structural integrity, disease resistance and stress tolerance, ultimately contributing to more robust plants and improved yield. Silica enriches enzyme activity, particularly antioxidant enzymes like superoxide dismutase (SOD), catalase anhydrase and IAA oxidase contributing to stress tolerance with improved productivity. Its deposition within plant tissues strengthens cell walls, fortifies defences against pathogens and enables better adaptation to environmental fluctuations, ensuring the resilience and productivity of these vital crops. Si effect on mitigating biotic stresses including rice stem borer, leaf folder, sheath blight and blast by triggering physical and biochemical defence mechanisms; abiotic stresses, frequent in rice crop like salinity, drought, and heavy metal toxicity by improving osmotic adjustment, safeguarding ion homeostasis, and reducing oxidative damage. [ABSTRACT FROM AUTHOR]

In this work, the interaction of K2SiF6 with LiCl–KCl-CsCl chloride melts was studied using cyclic voltammetry and atomic emission spectroscopy analysis, depending on their cationic composition in the temperature range from 550 to 665 °C. It has been determined that an increase in the CsCl/LiCl ratio leads to a decrease in the rate of decomposition of the K2SiF6 additive due to the formation of compounds with greater stability due to the replacement of the cation and the predominance of the corresponding reactions. Based on the results of ICP-AES, a decrease in the concentration of silicon ions in the melt during electrolysis was detected, and its final values in the melts at the end of the 12-h exposure were determined. During electrolysis, the silicon concentration also decreases, and in the case of a short electrolysis duration (up to 4 h), it is possible to maintain a sufficient concentration to be carried out without introducing additional K2SiF6 in the process. The optimal composition for electrodeposition was also determined, and it was found that a high LiCl content in the melt leads to the formation of lithium fluoride and its inclusion in the deposit. [ABSTRACT FROM AUTHOR]

Numerous abiotic and biotic stresses threaten sustainable agriculture under limited resources. Agriculture productivity is disrupted by these unpredictable environmental fluctuations, posing a serious threat to food security. As a beneficial nutrient, silicon (Si) application enhances biological functions, crop development and productivity. Silicon application has garnered attention for its ability to mitigate various stresses and has shown a highly significant response under conditions such as water scarcity, salinity, metal toxicity, thermal stress and nutrients deprivation. Additionally, it enhances defense mechanisms against fungal, bacterial and pest attacks. High crops production can be achieved by incorporating Si into the agricultural system to replace synthetic fertilizers. This approach can help overcome limitations in crop production posed by limited resources and unpredictable environmental conditions. The environmentally friendly Si application is replacement of synthetic toxic chemicals for sustainable agriculture to get maximum yield under limited resources and unpredictable environmental conditions, as well regulate the genes expression to mitigate the biotic and abiotic stresses. The keys genes involved in different metabolic pathways under Si application have discussed in this study, which will be more beneficial to develop stress resilient crops through CRISPR/CAS technology to overcome the food threat and agriculture sustainability. [ABSTRACT FROM AUTHOR]

The azalea lace bug (ALB), Stephanitis pyrioides (Scott) (Hemiptera: Tingidae), is a pest of azaleas and rhododendrons. The application of silicon (Si) to plants has been shown to accumulate in other plants and enhance defense to other plant pests. We evaluated whether Si applications decreased ALB infestation on rhododendron leaves and increased Si accumulation in leaves. Potted plants were treated with 4 or 8 weekly applications of calcium silicate and calcium carbonate (calcium control, Ca) via foliar or soil application. In 3 out of 4 choice studies, plants treated with calcium silicate or calcium carbonate had less frass deposition and oviposition by ALB compared to controls, but treated plants did not consistently have fewer ALB adults. Leaf damage was quantified in one study and leaves with more frass as an indicator of feeding had more visible damage. In no-choice studies, there were no differences between treatments in one study, but oviposition was greater on foliar/soil Si-treated plants than controls in another study. Since rhododendron aphids (Illinoia lambersi) appeared in the greenhouse during or after studies, we compared their colonization on previously treated rhododendrons. Infestation of new leaf rosettes or random leaves by I. lambersi was lower on plants sprayed with foliar silicon or calcium applied via soil in 2 studies. Treated rhododendrons did not accumulate extra Si or Ca in leaves compared to controls. In general, silicon or calcium application protected rhododendrons from ALB oviposition and aphid colonization in free-choice conditions, and may be part of an integrated pest management program. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)