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1. Model scenarios of climate change predict that warming and drought will occur simultaneously in the future in many regions. The capacity of woody species to modify their physiology and morphology in response to environmental conditions is widely recognized, but little is known about the responses of trees to reduced precipitation and increased temperature acting simultaneously. 2. In a semi-arid woodland, we assessed the responses in physiological (needle emergence, maximum photosynthesis, stomatal conductance, water use efficiency (WUE) and shoot elongation) and morphological (needle length and thickness, and leaf mass per area (LMA)) foliar traits of piñon pine (Pinus edulis) in response to three years of a 45% reduction in precipitation, a 4.8 °C increase in air temperature and their simultaneous effects. 3. A strong change in physiological and morphological traits in response to reduced precipitation was observed. Precipitation reduction delayed needle emergence, decreased photosynthesis and stomatal conductance, increased WUE, decreased shoot elongation and induced shorter needles with a higher LMA. Trees subjected to simultaneous reductions in precipitation and warming demonstrated a similar response. However, atmospheric warming did not induce a response in any of the measured traits. 4. Physiological and morphological traits of trees in this semi-arid climate were more responsive to changes in soil moisture than air temperature. Long-term exposure to seasonal drought stress in arid sites may have resulted in strong plastic responses to this first stressor. However, atmospheric warming probably was not experienced as a stress for trees in this warm and dry climate. Overall, our results indicate that in semi-arid ecosystems where tree functioning is already highly limited by soil water availability, atmospheric warming as anticipated with climate change may have less impact on foliar trait responses than previously thought.

Background Picea species are distributed and planted world-wide due to their great ecological and economic values. It has been reported that Picea species vary widely in growth traits in a given environment, which reflects genetic and phenotypic differences among species. However, key physiological processes underlying tree growth and the influencing factors on them are still unknown. Results Here, we examined needle structures, needle chemical components, physiological characteristics and growth traits across five Picea species in a common garden in Tianshui, Gansu province in China: Picea glauca , P. mariana , P. likiangensis , P. koraiensis , and P. crassifolia , among which P. glauca and P. mariana were introduced from North America, P. likiangensis was from Lijiang, Yunan province in China, P. koraiensis was from Yichun, Heilongjiang province in China, and P. crassifolia was native to the experimental site. It was found that nearly all traits varied significantly among species. Tissue-level anatomical characteristics and leaf mass per area (LMA) were affected by needle size, but the variations of them were not associated with the variations in photosynthetic and biochemical capacity among species. Variations in area-based maximum photosynthesis (P nmax ) were affected by stomatal conductance (g s ), mesophyll conductance (g m ) and biochemical parameters including maximum carboxylation rate (V cmax ), and maximum electron transport rate (J max ). The fraction of N allocated to different photosynthetic apparatus displayed contrasting values among species, which contributed to the species variations in photosynthetic nitrogen use efficiency (PNUE) and P nmax . Additionally, all growth traits were positively correlated with P nmax and PNUE. Conclusion Needle structures are less important than needle biochemical parameters in determining the variations in photosynthetic capacity across the five Picea species. P nmax and PNUE are closedly associated with the fraction of N allocated to photosynthetic apparatus (P photo ) compared with leaf N content per area (N area ). The tremendous growth differences among the five Picea species were substantially related to the interspecies variation in P nmax and PNUE.

Needle structure was analyzed in three Juniperus communis taxa from different localities in central Slovakia. The main aim was to test the hybrid origin hypothesis of J. communis nothovar. intermedia (Schur) Nyman, defined as a cross between J. communis L. ssp. communis and J. communis ssp. nana (Hook.) Syme. While DNA-based analyses remain the most reliable tool for inferring evolutionary history, comparative needle morphology can provide complementary evidence, including diagnostic traits for taxonomic delimitation. In this study, we evaluated three morphometric and sixteen anatomical needle traits, measured via microscopy in ten shrubs per taxon. The analyses indicated that most traits in nothovar. intermedia matched one of the parents, with only two traits proving strongly diagnostic, separating all three taxa: needle length, which showed an intermediate mean phenotype in nothovar. intermedia (R2 = 0.824, p = 0.011; between parents), and vascular bundle height, which displayed a transgressive pattern (R2 = 0.552, p = 0.031; between parents). Although the diagnostic value of individual traits for hybrid detection was generally weak, a phylogenetic network analysis based on six diagnostic traits that separated individuals of the parental taxa provided evidence for reticulate evolution. These results support the hybrid origin of J. communis nothovar. intermedia and highlight needle traits with potential value for distinguishing ssp. communis and ssp. nana in natural populations, which may assist in taxonomic delimitation and inform future conservation assessments.

Siberian stone pine (Pinus sibirica Du Tour) is one of the most common trees in Siberia. Its natural range is from the Ural Mountains to the Aldan river and from the Arctic Circle to northern Mongolia. The climate in natural Siberian stone pine sites influences the whole plant organism, particularly its needle structure, and the response to thisoccurs at specific morphological and anatomical levels. The genotypical and environmental effects on needle structure in different Siberianstone pine ecotypes are very little known. One effective way to examine and to separate genotypical effects from environmental ones is byusing a common garden experiment. The purpose is to analyze morphological and anatomical needle variability in Siberian stone pinemarginal populations that have been grown in provenance plantations in southern West Siberia, Russia. The needle samples were collectedin the provenance plantation located 30 km south of Tomsk (the southeastern West Siberian Plain, southern limit of the taiga zone,optimum site conditions for Siberian stone pine). We investigated the grafts of mother trees taken from natural sites. Four ecotypeswere selected for the study. Three ecotypes originated from northern (Urengoy), western (Neviyansk), and eastern (Severobaikalsk)marginal populations. The fourth, the Tomsk ecotype, was a local control. The local Tomsk ecotype grows on a site where natural conditions are worse due to reduction of mean annual temperature and increase of the humid factor northward, humidity reduction eastward and its rise westward. Variability of 10 needle morphologicaland anatomical characteristics was studied. The northern ecotype had smaller needle length (28%), leaf cross-section area (21%), mesophyll area (29%), mesophyll cell size (27%), and conducting bundle area (16%) but the number of stomata per unit leaf area increased by 16% over the local Tomsk ecotype. The resin canal area, epidermal andhypodermal cell thickness, and stomata size were equal to both the northern and local ecotypes. The leaf cross-section and mesophyllarea in the western ecotypes decreased by 20% and 23%, respectively, but stomata size increased by 12%. The needle length, mesophyllcell size, conducting bundle area, resin canal area, the number of stomata per unit leaf area, and epidermal and hypodermal cell thicknessdid not differ significantly from the same characteristics in the Tomsk ecotype. The leaf cross-section area, mesophyll area, and mesophyllcell size in the eastern ecotype decreased by 22%, 37% and 20% respectively, as compared with the local ecotype. All other studiedneedle characteristics did not differ from the local ecotype. The common morphological and anatomical parameters did not change fromsouth to north and from west to east (resin canal area and hypodermal cell thickness) and parameters varied in each ecotype. For example,needle length, conducting bundle area, and the number of stomata per unit leaf area changed along latitude but did not changealong longitude. Conversely, stomata size and epidermal cell thickness changed along longitude but did not change along latitude. Thus the morphological and anatomical characteristics were specific for each ecotype. The parameter variability of the needle structure is hypothesized to relate to graft geographical provenance that depends on genotype and adaptation properties of mother trees.

This study presents a comprehensive analysis of some key manufacturing parameters of Sports Compression Socks (SCS), aiming to optimize their performance characteristics for athletic applications. We investigated the interplay of material selection (Polyamide and Polyester), knitting structures (Pique and Drop Needle), and processing methods (E-wash, Dip wash, and Direct Press) on the functional properties of SCS. Our experimental design employed a full factorial approach, utilizing the Taguchi method for robust data analysis and the VIKOR (VlseKriterijuska Optimizacija I Komoromisno Resenje) technique for multi-criteria optimization. Key performance indicators assessed included compression pressure, fabric thickness, breathability (air permeability and Overall Moisture Management Capacity), and serviceability (pilling resistance and dimensional stability). The collected data underwent rigorous scrutiny using one-way analysis of variance (ANOVA) to assess their significance, validated by p-values (p < 0.05). Further insight into the significance and contribution percentages of each factor was gained through ANOVA (α = 0.10) and visualized using a pie chart. Results demonstrated significant influences of knitting structures and processing methods on the physical and performance characteristics of SCS. Particularly, the Nylon E-wash Pique (NEWP) combination emerged as the most effective, providing a balanced profile of breathability, compression, and durability. Overall, the study contributes to the optimization of SCS performance characteristics for athletic applications, through a comprehensive analysis of key manufacturing parameters, with practical implications for manufacturers. These insights are pivotal for guiding manufacturers in producing high-quality, effective SCS that meet diverse consumer needs. The study advances the understanding of SCS design, proposing strategic approaches that consider important material and manufacturing perspectives. Future research directions include comparing pressure values in yarn-dyed and sock-dyed processes to further enhance the quality of compression garments.

Micro/nano structures with morphological gradients possess unique physical properties and significant applications in various research domains. This study proposes a straightforward and precise method for fabricating micro/nano structures with morphological gradients utilizing single-voxel synchronous control and a nano-piezoelectric translation stage in a two-photon laser direct writing technique. To address the defocusing issue in large-scale fabrication, a methodology for laser focus dynamic proactive compensation was developed based on fluorescence image analysis, which can achieve high-precision compensation of laser focus within the entire range of the nano-piezoelectric translation stage. Subsequently, the fabrication of micro/nano dual needle structures with morphological gradients were implemented by employing different writing speeds and voxel positions. The minimum height of the tip in the dual needle structure is 80 nm, with a linewidth of 171 nm, and a dual needle total length reaching 200 μm. Based on SEM (scanning electron microscope) and AFM (atomic force microscope) characterization, the dual needle structures fabricated by the method proposed in this study exhibit high symmetry and nanoscale gradient accuracy. Additionally, the fabrication of hexagonal lattice periodic structures assembled from morphological gradient needle structures and the size gradient Archimedean spiral structures validate the capability of the single voxel-based fabrication and proactive focus compensation method for complex gradient structure fabrication.

Several studies have looked at how individual environmental factors influence needle morphology in conifer trees, but interacting effects between drought and canopy position have received little attention. In this study, we characterized morphological responses to experimentally induced drought stress in sun exposed and shaded current-year Norway spruce needles. In the drought plot trees were suffering mild drought stress, with an average soil water potential at 50 cm depth of -0.4 MPa. In general, morphological needle traits had greater values in sun needles in the upper canopy than in shaded needles in the lower canopy. Needle morphology 15 months after the onset of drought was determined by canopy position, as only sun needle morphology was affected by drought. Thus, canopy position was a stronger morphogenic factor determining needle structure than was water availability. The largest influence of mild drought was observed for needle length, projected needle area and total needle area, which all were reduced by ~27% relative to control trees. Needle thickness and needle width showed contrasting sensitivity to drought, as drought only affected needle thickness (10% reduction). Needle dry mass, leaf mass per area and needle density were not affected 15 months after the onset of mild drought. Our results highlight the importance of considering canopy position as well as water availability when comparing needle structure or function between conifer species. More knowledge about how different canopy parts of Norway spruce adapt to drought is important to understand forest productivity under changing environmental conditions.

Advanced dispensing technology is urgently needed to improve the jetting performance of fluid to meet the requirements of electronic product integration and miniaturization. In this work, an on–off valve piezostack-driven dispenser was used as a study object to investigate the effect of needle structure on jetting performance. Based on fluid dynamics, we investigated nozzle cavity pressure and jet velocity during the dispensing process using theoretical simulation for needles with and without a side cap. The results showed that the needle with a side cap had larger jet velocity and was capable of generating 8.27 MPa of pressure in the nozzle cavity, which was 2.39 times larger than the needle without a side cap. Further research on the influence of the nozzle and needle structural parameters showed that a nozzle conic angle of 85°–105°, needle conic angle of 10°–35°, and side clearance of 0.1–0.3 mm produced a dispenser with a large jet velocity and stable performance, capable of dispensing microscale droplets. Finally, a smaller droplet diameter of 0.42 mm was achieved in experiments using a glycerol/ethanol mixture, with a variation range of ± 4.61%.

Chloroplast number per cell is a frequently examined quantitative anatomical parameter, often estimated by counting chloroplast profiles in two-dimensional (2D) sections of mesophyll cells. However, a mesophyll cell is a three-dimensional (3D) structure and this has to be taken into account when quantifying its internal structure. We compared 2D and 3D approaches to chloroplast counting from different points of view: (i) in practical measurements of mesophyll cells of Norway spruce needles, (ii) in a 3D model of a mesophyll cell with chloroplasts, and (iii) using a theoretical analysis. We applied, for the first time, the stereological method of an optical disector based on counting chloroplasts in stacks of spruce needle optical cross-sections acquired by confocal laser-scanning microscopy. This estimate was compared with counting chloroplast profiles in 2D sections from the same stacks of sections. Comparing practical measurements of mesophyll cells, calculations performed in a 3D model of a cell with chloroplasts as well as a theoretical analysis showed that the 2D approach yielded biased results, while the underestimation could be up to 10-fold. We proved that the frequently used method for counting chloroplasts in a mesophyll cell by counting their profiles in 2D sections did not give correct results. We concluded that the present disector method can be efficiently used for unbiased estimation of chloroplast number per mesophyll cell. This should be the method of choice, especially in coniferous needles and leaves with mesophyll cells with lignified cell walls where maceration methods are difficult or impossible to use.