Search Results (385)

This study, conducted in Southern Italy in 2023, investigated the effects of a dynamic agrivoltaics (AV) system on microclimate, water consumption, plant growth, and essential oil yield in six medicinal species: lavender (Lavandula angustifolia L. ‘Royal purple’), lemmon thyme (Thymus citriodorus (Pers.) Schreb. ar. ‘Aureus’), common thyme (Thymus vulgaris L.), rosemary (Salvia rosmarinus Spenn. ‘Severn seas’), mint (Mentha spicata L. ‘Moroccan’), and sage (Salvia officinalis L. subsp. Officinalis). Due to the rotating solar panels, two distinct ground zones were identified: a consistently shaded area under the panels (UP), and a partially shaded area between the panels (BP). These were compared to an adjacent full-sun control area (T). Microclimate parameters, including solar radiation, air and leaf infrared temperature, and soil temperature, were recorded throughout the cultivation season. Reference evapotranspiration (ET_O) was calculated using Turc’s method, and crop evapotranspiration (ET_C) was estimated with species-specific crop coefficients (K_C). Results showed significantly lower microclimatic values in the UP plot compared to both BP and especially T, resulting in ET_C reductions of 81.1% in UP and 13.1% in BP relative to T, an advantage in water-scarce environments. Growth and yield responses varied among species and treatment plots. Except for mint, all species showed a significant reduction in fresh biomass (40.1% to 48.8%) under the high shading of UP compared to T. However, no biomass reductions were observed in BP. Notably, essential oil yields were higher in both UP and BP plots (0.60–2.63%) compared to the T plot (0.51–1.90%). These findings demonstrate that dynamic AV systems can enhance water use efficiency and essential oil yield, offering promising opportunities for sustainable, high-quality medicinal crop production in arid and semi-arid regions. Full article

Background: The rising demand for aesthetic dental treatments has spurred interest in peroxide-free color correctors as alternatives to traditional hydrogen peroxide formulations, which are associated with tooth sensitivity and potential enamel demineralization. This systematic review evaluates the whitening efficacy and safety profile of hydrogen peroxide-free color corrector (HPFCC) products, focusing on color change metrics, enamel and dentin integrity, and adverse effects. Methods: Following PRISMA guidelines, we searched PubMed, Scopus, and Web of Science throughout January 2025 for randomized controlled trials, observational studies, and in vitro experiments comparing HPFCC to placebo or peroxide-based agents. The data extraction covered study design, sample characteristics, intervention details, shade improvement (ΔE00 or CIE Lab), enamel/dentin mechanical properties (microhardness, roughness, elastic modulus), and incidence of sensitivity or tissue irritation. Risk of bias was assessed using the Cochrane tool for clinical studies and the QUIN tool for in vitro research. Results: Six studies (n = 20–80 samples or subjects) met the inclusion criteria. In vitro, HPFCC achieved mean ΔE00 values of 3.5 (bovine incisors; n = 80) and 2.8 (human molars; n = 20), versus up to 8.9 for carbamide peroxide (p < 0.01). Across studies, HPFCC achieved a mean ΔE00 of 2.8–3.5 surpassing the perceptibility threshold of 2.7 and approaching the clinical acceptability benchmark of 3.3. Surface microhardness increased by 12.9 ± 11.7 VHN with HPFCC (p < 0.001), and ultramicrohardness rose by 110 VHN over 56 days in prolonged use studies. No significant enamel erosion or dentin roughness changes were observed, and the sensitivity incidence remained below 3%. Conclusions: These findings derive from one clinical trial (n = 60) and five in vitro studies (n = 20–80), encompassing violet-pigment serums and gels with differing concentrations. Due to heterogeneity in designs, formulations, and outcome measures, we conducted a narrative synthesis rather than a meta-analysis. Although HPFCC ΔE00 values were lower than those of carbamide peroxide, they consistently exceeded perceptibility thresholds while maintaining enamel integrity and causing sensitivity in fewer than 3% of subjects, supporting HPFCCs as moderate but safe alternatives for young patients. Full article

Objectives: The aim of this study was to evaluate the effectiveness of spectrophotometers for objective tooth color measurement, particularly in bleaching procedures enhanced by digital positioning templates. Methods: Tooth color registration was conducted using both subjective methods with shade guides and objective methods with spectrophotometers. Spectrophotometers were chosen for their ability to provide objective, quantifiable, and reproducible results, crucial for monitoring color modifications accurately. Digital workflows were implemented to enhance the registration process further. These workflows included providing a precise positioning matrix for spectrophotometer sensors and optimizing working models to ensure high-quality therapeutic splints. Results: The use of spectrophotometers demonstrated superior performance in registering tooth color objectively compared to subjective shade guides. Digital workflows significantly improved the precision and efficiency of spectrophotometer measurements through a digital matrix, enhancing the quality of therapeutic splints obtained. Conclusions: Spectrophotometers are recommended for objective and precise tooth color registration, particularly in bleaching procedures. Integrating a digital positioning matrix enhances measurement accuracy and reliability, supporting effective monitoring and treatment outcomes. Full article

Pinus yunnanensis, a native tree species in southwest China, is shading-tolerant and ecologically significant. Light has a critical impact on plant physiology, and decapitation improves canopy light penetration and utilization efficiency. The study of allometric relationships is well-known in forestry, forest ecology, and related fields. Under control (full daylight exposure, 0% shading), L1 (partial shading, 25% shading), L2 (medium shading, 50% shading), and L3 (serious shading, 75% shading) levels, this study used the decapitation method. The results confirmed the effectiveness of decapitation in annual P. yunnanensis and showed that the main stem maintained isometric growth in all shading treatments, accounting for 26.8% of the individual plant biomass, and exhibited dominance in biomass allocation and high shading sensitivity. These results also showed that lateral roots exhibited a substantial biomass proportion of 12.8% and maintained more than 0.5 of higher plasticity indices across most treatments. Moreover, the lateral root exhibited both the lowest slope in 0.5817 and the highest significance (p = 0.023), transitioning from isometric to allometric growth under L1 shading treatment. Importantly, there was a positive correlation between the biomass allocation of an individual plant and that of all components of annual P. yunnanensis. In addition, the synchronized allocation between main roots and lateral branches, as well as between main stems and lateral roots, suggested functional integration between corresponding belowground and aboveground structures to maintain balanced resource acquisition and architectural stability. At the same time, it has been proved that the growth of lateral roots can be accelerated through decapitation. Important scientific implications for annual P. yunnanensis management were derived from these shading experiments on allometric growth. Full article

To determine optimal light conditions for Hopea hainanensis Merr. & Chun seedling growth, this study examined growth and physiological parameters under four shading treatments (0%, 30%, 60%, and 90% irradiance reduction) over 12 months. Shading significantly affected the growth adaptability of seedlings. As shading increased, height, leaf traits (area, length, width), and light saturation point all initially increased, peaked at 30% shading, and then decreased. Conversely, basal diameter, leaf thickness, the maximum net photosynthetic rate, net photosynthetic rate, photosynthetic quantum efficiency, transpiration rate, and stomatal conductance progressively declined as shading increased. Biomass accumulation (in stems and roots), dark respiration rate, and light compensation point exhibited a U-shaped response to shading, being minimized under low or moderate shading. All shading treatments significantly reduced biomass and photosynthetic performance compared to controls. Multivariate analysis identified 0%–30% shading as optimal for cultivation, with 30% shading enhancing photomorphogenic responses while maintaining photosynthetic efficiency. The study findings suggest a novel seedling cultivation protocol for nursery use, in which initial establishment occurs under 30% shading to maximize vertical elongation, followed by the progressive reduction in shading to stimulate radial growth and optimal biomass partitioning. This approach mimics natural canopy gap dynamics, effectively mimicking natural regeneration in tropical rainforest ecosystems. Full article

In order to recycle plastic waste back to food contact materials (FCMs), it is necessary to identify hazardous substances in plastic packaging that pose a toxicological risk. Printing inks on plastics are not yet designed to withstand the high heat stress of mechanical recycling processes and therefore require hazard identification. In this study, virgin polypropylene (PP) foils were printed with different types of inks (UV-cured, water-based) and colour shades. Thermal analysis of printed foils and pigments was performed using differential scanning calorimetry (DSC). Samples were then thermally treated below and above measured thermal events at 120 °C, 160 °C, 200 °C or 240 °C for 30 min. Subsequently, migration tests and miniaturised Ames tests were performed. Four out of thirteen printed foils and all three pigments showed positive results for mutagenicity in miniaturised Ames tests after thermal treatment at 240 °C. Additionally, pre-incubation Plate Ames tests (according to OECD 471) were performed on three pigments and one printed foil, yielding two positive results after thermal treatment at 240 °C. These results indicate that certain ink components form hazardous decomposition products when heated up to a temperature of 240 °C. However, further research is needed to gain a better understanding of the chemical processes that occur during high thermal treatment. Full article

Underground cast-in-place pipes (CIPP, Diameter of 2’–5’) are used to transport water for the Phoenix, AZ area. These pipes have developed leaks due to their age and changes in the environment, resulting in a significant waste of water. Currently, leaks can only be identified when water pools above ground occur and are then manually confirmed through the inside of the pipe, requiring the shutdown of the water system. However, many leaks may not develop a puddle of water, making them even harder to identify. The primary objective of this research was to develop an inspection method utilizing drone-based infrared imagery to remotely and non-invasively sense thermal signatures of abnormal soil moisture underneath urban surface treatments caused by the leakage of water pipelines during the regular operation of water transportation. During the field tests, five known leak sites were evaluated using an intensive experimental procedure that involved conducting multiple flights at each test site and a stringent filtration process for the measured temperature data. A detectable thermal signal was observed at four of the five known leak sites, and these abnormal thermal signals directly overlapped with the location of the known leaks provided by the utility company. A strong correlation between ground temperature and shading before sunset was observed in the temperature data collected at night. Thus, a shadow and solar energy model was implemented to estimate the position of shadows and energy flux at given times based on the elevation of the surrounding structures. Data fusion between the metrics of shadow time, solar energy, and the temperature profile was utilized to filter the existing points of interest further. When shadows and solar energy were considered, the final detection rate of drone-based infrared imaging was determined to be 60%. Full article

Limited comparative research exists on evaluating the performance of tomato rootstocks under different growing methods, resulting in growers facing challenges when deciding which rootstock and growing method to use for improved yield. The effect of growing methods (scion of a single stem or double stems and non-grafted plant as the control) and rootstock cultivars (Goldbac, SVTX6258, and Booster) on the yield and quality of tomatoes grown in a plastic tunnel and a shade net structure was investigated. The splice grafting method was followed. In a plastic tunnel experiment, grafting and rootstock cultivar did not significantly affect the total soluble solids (TSS), pH, and electrical conductivity (EC) of the tomato juice, as well as percentage weight loss, yield, and fruit firmness. However, the Booster rootstock with a scion of 2 stems had high fruit Mg, K, P, and Fe contents, while the Goldbac rootstock with a scion of 1 stem and 2 stems had high fruit Ca and Fe contents compared to other treatments. The Goldbac and Booster rootstocks grafted to a scion of 2 stems had a high marketable yield. In a shade net experiment, the Booster rootstock with a scion of 2 stems had a high early harvest and total yield of tomatoes, followed by the Goldbac rootstock with a scion of 2 stems. Higher incidences of fruit cracking were noticed on the Booster rootstock grafted with a scion of a single stem. Generally, grafted plants on Booster and Goldbac had improved Mg, K, and P contents, unlike SVTX6258 with a scion of 1 stem. The Booster rootstock with a scion of 2 stems had significantly higher Mg, K, and P contents, while the sodium (Na) fruit content was high on the SVTX6258 rootstock with a scion of 1 stem. Grafting did not significantly affect fruit physiological disorders, weight loss, and TSS, or pH and EC of tomato juice. Grafting with a scion of two stems at the seedling stage significantly improved the tomato fruit mineral content and the total and marketable yield in a plastic tunnel and a shade net structure. Full article

Biochar has attracted interest in viticulture for its potential to enhance nutrient uptake and improve grapevine physiology under changing climatic conditions, particularly in Mediterranean regions. However, the widespread adoption of biochar has been limited due to economic and logistical constraints associated with its large-scale application. To address these barriers hindering the widespread adoption of biochar, this study investigates the effects of foliar-applied water suspensions of biochar at concentrations of 300 mg/L (B300), 600 mg/L (B600), and 1200 mg/L (B1200), compared to a water-only control (C), as a practical alternative application method. The research focused on Malvazija istarska (Vitis vinifera L.), an indigenous Croatian grapevine variety, conducted in an experimental vineyard in Poreč, Croatia. The key physiological parameters examined included photo-synthetic activity, leaf water potential, the elemental composition of the grapevine leaves, and grape yield. Foliar applications were administered three times during the growing season, with five replicates per treatment. The results indicated that biochar treatments had no significant impact on photosynthetic activity, suggesting that foliar application did not cause leaf shading. However, higher biochar concentrations (B600 and B1200) led to increased leaf concentrations of nitrogen (2.1–3.8%), potassium (10.1–18.4 g/kg), sulfur (2.2–2.5 g/kg), boron (65.1–83.6 mg/kg), and manganese (42.4–69.8 mg/kg) compared to B300 and C treatments. Conversely, magnesium content decreased (2.1–2.7 g/kg), likely due to potassium–magnesium antagonism. Furthermore, the B600 treatment produced the highest grape yield (2.67 kg/vine), representing up to a 37% increase compared to other treatments. These findings suggest that the foliar application of biochar can be an effective and sustainable strategy to enhance vineyard productivity. Moreover, it offers a circular economy approach by valorizing grapevine pruning waste as a biochar source. Full article

Background: This study aimed to evaluate the effect of in-office bleaching with 38% hydrogen peroxide (HP) on the surface roughness of a nanohybrid composite resin by comparing two measurement techniques: Scanning Electron Microscopy (SEM) and profilometry. Methods: Sixty composite specimens of identical shade and thickness were prepared, light-cured, and polished following the manufacturer’s guidelines. These samples were divided into six groups based on the applied surface treatments: group 1: fresh composite (the control group), group 2: old composite, group 3: bleached fresh composite, group 4: bleached old composite, group 5: old repolished composite, and group 6: old repolished bleached composite. Surface roughness was measured using profilometry and SEM. Results: Pearson correlation analysis revealed a moderately significant linear relationship (r = 0.548, p < 0.001) between the surface roughness measurements obtained using SEM and the profilometer, indicating that both methods provide comparable results. A comparison of most groups showed significant differences (p < 0.001), highlighting the increased surface roughness observed after bleaching both fresh and aged composites. Conclusions: Bleaching increased the surface roughness of nanohybrid composites. It might be better to use SEM and a profilometer together to obtain a more comprehensive understanding of the surface characteristics. Full article

Understanding the seasonal regulation of transpiration and stomatal conductance is critical for evaluating plant water-use strategies in response to environmental variability. This study assessed these physiological traits in three dominant savanna tree species (Piliostigma thonningii (Schumach.) Milne-Redh., Combretum molle R.Br. ex G.Don, and Balanites aegyptiaca (L.) Delile) in Ruma National Park, Kenya. Measurements were taken during wet and dry seasons under varying canopy light conditions (light-exposed vs. shaded leaves) and soil moisture regimes. A randomized design with four treatments and three replicates was employed. Results showed significantly higher transpiration and stomatal conductance during wet seasons, especially in sunlit leaves (p < 0.05). P. thonningii exhibited the highest rates of transpiration (9 mmol m⁻² s⁻¹) and stomatal conductance (~2.2 mmol m⁻² s⁻¹) in light conditions, while B. aegyptiaca maintained consistently low values, reflecting a drought-tolerant strategy. C. molle demonstrated intermediate responses, suggesting a balance between water conservation and resource use. Despite seasonal trends, low R² values indicated that internal physiological regulation outweighed the influence of external climatic drivers. These findings reveal species-specific water-use strategies and highlight the ecological significance of leaf-level responses to light and moisture availability in tropical savannas. The study provides valuable insights for forest management and climate-resilient restoration planning in water-limited ecosystems. Full article

Dairy cows are suffering from heat stress (HS) worldwide, and this has become a continual challenge in dairy production systems. The objective of this study was to investigate the effects of the shade of poplar trees on alleviating HS via measuring milk production, nutrient digestibility, immunity, and antioxidant capability in the serum of dairy cows in open cowsheds. A total of 540 lactating Holstein cows were assigned to 2 groups (3 cowsheds per group, 90 cows per cowshed), including the treatment group with poplar trees on the west side of sheds and the control group without trees. This study was carried out in the early-hot season, hot season, and late-hot season. The results showed the following: (1) During the hot season, shaded cows exhibited lower respiration rate (p < 0.05) and higher dry matter intake (p < 0.05) and daily milk yield (p < 0.05), compared with the control. Also, apparent digestibility of crude protein, acid detergent fiber, and neutral detergent fiber demonstrated an increase (p < 0.05) in shaded cows during the hot season. (2) Total antioxidant capacity and superoxide dismutase activity in the serum of shaded cows increased (p < 0.05) during the hot season and late-hot season, compared with the control. (3) Serum interleukin-4, immunoglobulin G, and immunoglobulin M concentrations of shaded cows were greater (p < 0.05) than the control during the hot season. Additionally, serum concentrations of HSP60, HSP70, and HSP90 in shaded cows showed a decrease (p < 0.05) during the hot season. In conclusion, shade from poplar trees can mitigate the adverse impact of high-temperature environments on cows in open cowsheds. Full article

Dense planting and intercropping are the main ways to improve soybean production. However, both confront inter- and intra-crop shading stress. This leads to stem elongation, resulting in lodging and yield losses. Most previous studies have focused on the later growth stages for shade tolerance. However, it has been found that the seedling stage is crucial, and understanding the genetic basis of shade tolerance at this stage is pivotal for yield improvement. In this study, 310 soybean accessions were used to evaluate shade tolerance under greenhouse conditions. Plant height (PH), main stem length (MSL), and hypocotyl length (HL) were examined at seedling stage, and their treatment/control ratios (PH_r, MSL_r, HL_r) were used for genetic dissection of shade tolerance. Their overall phenotypic variation and heritability (H²) ranged 22.97–36.85% and 31.66–83.81%, respectively. RTM-GWAS identified 12, 10, and 6 QTLs associated with PH_r, MSL_r, and HL_r, respectively. Among these, Block_17_11907536_11926235 was associated with both PH_r and MSL_r, and Block_1_55630414_55715065 associated with the HL_r trait showed the highest contribution (R² = 10.38%). Additionally, seven promising candidate genes, primarily linked to ethylene-responsive transcription factors, were proposed, supported by their established roles in plant development and stress responses, as evidenced in prior studies. The germplasm, QTLs, and candidate genes identified in this study improve our understanding of shade tolerance and have the potential to accelerate the breeding of shade-resilient soybeans. Full article

Fritillaria thunbergii Miq., a medicinal plant rich in steroidal alkaloids, produces bulbs that clear heat, resolve phlegm, and detoxify. However, excessive yield-oriented cultivation has reduced the number of F. thunbergii plants that meet commercial standards. This study explored the effects of potassium application and shading on the bulb biomass and medicinal substance content of F. thunbergii. Shading increased the active ingredient content in bulbs by approximately 20.71% but reduced biomass by approximately 17.24%. Fertilization with different potassium concentrations under shading (K1S–K3S) alleviated shading-induced biomass reduction and increased active ingredient accumulation, with the K2S and K3S groups yielding significantly better results than the K1S group. Pharmacological experiments showed that the K2S group exerted the best antitussive, expectorant, and anti-inflammatory effects. Metabolome analysis showed that compared with those in the controls, peiminine, peimine, imperialine, solasodine, and cyclopamine were the most abundant steroidal alkaloids under K2S treatment. Transcriptome analysis identified key genes and biosynthetic pathways for major steroidal alkaloids, namely, farnesyl pyrophosphate synthase (FtFPS) involved in steroidal alkaloid biosynthesis. Transcription factor analysis revealed that nine transcription factors predominantly expressed under the K2S treatment might regulate steroidal alkaloid biosynthesis. Furthermore, FtFPS was identified as a hub gene in the co-expression network and was verified to catalyze the biosynthesis of farnesyl pyrophosphate. The interaction between FtFPS and FtAP2/ERF was verified through yeast two-hybrid experiments. These findings offer new insights into the steroidal alkaloid biosynthesis mechanism triggered in F. thunbergii by potassium application and shading, supporting ecological strategies to enhance steroidal alkaloid levels in this species. Full article

Begonia semperflorens (B. semperflorens) is a popular ornamental plant widely used in landscapes such as plazas and flower beds, and it is also commonly grown as a potted plant indoors. It is known for its adaptability to high temperatures, drought, and shade. Under heat-tolerant conditions, heat shock transcription factors (HSFs) are key transcriptional regulatory proteins that play crucial roles in cellular processes. Despite extensive studies on the HSF family in various species, there has been no specific analysis targeting B. semperflorens. In this study, we identified 37 members of the BsHSF gene family in B. semperflorens based on its genome scaffold, which are unevenly distributed across the genome. Phylogenetic analysis reveals that these 37 members can be divided into three subfamilies. Analysis of their physicochemical properties shows significant diversity among these proteins. Except for the BsHSFB7 protein located in the cytoplasm, all other BsHSF proteins were found to be nuclear-localized. A comparison of the amino acid sequences indicates that all BsHSF proteins contain a conserved DNA-binding domain structure. Analysis of the promoter cis-acting elements also suggests that BsHSFs may be associated with heat stress and plant secondary metabolism. We further investigated the duplication events of BsHSF genes and their collinearity with genes from other Begonia species. Finally, through real-time quantitative PCR, we examined the expression patterns of the 37 BsHSFs in different plant tissues (roots, stems, leaves, and flowers) and their expression levels under heat stress treatment. The results show that, except for BsHSF29, all BsHSFs were expressed in various tissues, with varying expression levels across tissues. Except for BsHSF33 and BsHSF34, the expression levels of almost all BsHSF genes increased in response to heat treatment. In summary, these findings provide a better understanding of the role and regulatory mechanisms of HSFs in the heat stress response of B. semperflorens and lay the foundation for further exploration of the biological functions of BsHSFs in the stress responses of B. semperflorens. Full article