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Introduction: In the face of escalating climate change, conserving fir forests in southeastern Tibet is paramount. These forests uphold Tibetan biodiversity and support crucial ecological services. Methods: This study used the typical plot method to investigate the survival status and development trends of three Chinese endemic Abies species, namely, Abies georgei var. smithii , Abies chayuensis , and Abies delavayi var. motuoensis , from the diameter structure, static life table, and survival curve. Results: The results revealed that 1) the density of Abies georgei var. smithii , Abies chayuensis , and Abies delavayi var. motuoensis in the community is 408, 320, and 103 trees per hectare, respectively. The structure of the diameter class of the three species of fir trees is a pyramid shape. As the diameter class increases, the number of each population fluctuates to varying degrees, and there is a lack of many medium- and large-diameter trees. 2) The survival curve of Abies georgei var. smithii tends to be similar to the Deevey type II curves, whereas the survival curves of Abies chayuensis and Abies delavayi var. motuoensis tend to be similar to the Deevey type III curves. Various population structures are growth-oriented but highly sensitive to external random disturbances, with mortality and disappearance rates multiple times, indicating poor population development. Survival analysis reveals that all populations begin to decline after the middle age range and that the age structure is relatively unstable. Discussion: The results of this study contribute to revealing the structural characteristics and dynamic patterns of various spruce populations, providing a theoretical basis for the management and sustainable utilization of fir forests in southeastern Tibet. [ABSTRACT FROM AUTHOR]

Coniferous forests are under severe threat of the rapid anthropogenic climate warming. Abies (firs), the fourth‐largest conifer genus, is a keystone component of the boreal and temperate dark‐coniferous forests and harbors a remarkably large number of relict taxa. However, the uncertainty of the phylogenetic and biogeographic history of Abies significantly impedes our prediction of future dynamics and efficient conservation of firs. In this study, using 1,533 nuclear genes generated from transcriptome sequencing and a complete sampling of all widely recognized species, we have successfully reconstructed a robust phylogeny of global firs, in which four clades are strongly supported and all intersectional relationships are resolved, although phylogenetic discordance caused mainly by incomplete lineage sorting and hybridization was detected. Molecular dating and ancestral area reconstruction suggest a Northern Hemisphere high‐latitude origin of Abies during the Late Cretaceous, but all extant firs diversified during the Miocene to the Pleistocene, and multiple continental and intercontinental dispersals took place in response to the late Neogene climate cooling and orogenic movements. Notably, four critically endangered firs endemic to subtropical mountains of China, including A. beshanzuensis, A. ziyuanensis, A. fanjingshanensis and A. yuanbaoshanensis from east to west, have different origins and evolutionary histories. Moreover, three hotspots of species richness, including western North America, central Japan, and the Hengduan Mountains, were identified in Abies. Elevation and precipitation, particularly precipitation of the coldest quarter, are the most significant environmental factors driving the global distribution pattern of fir species diversity. Some morphological traits are evolutionarily constrained, and those linked to elevational variation (e.g., purple cone) and cold resistance (e.g., pubescent branch and resinous bud) may have contributed to the diversification of global firs. Our study sheds new light on the spatiotemporal evolution of global firs, which will be of great help to forest management and species conservation in a warming world. [ABSTRACT FROM AUTHOR]

A series of double molybdates with palmierite-related structure phosphors K 5 Yb 1- x (MoO 4) 4 : x Er3+ were synthesized by a solid-state method. It has been demonstrated that the K 5 Yb 1- x (MoO 4) 4 : x Er3+ phosphors are capable of exhibiting the characteristic green and red UC emission of Er3+ ions with excitation at 980 nm. Moreover, the green light emission is far more than the red light emission, so that the sample emits a powerful green light, which belongs to the two-photon absorption process. The upconversion efficiency is peaked when the content of Er3+ ions is 10 mol %. The optical thermometry properties of phosphors were explored by observing that the green UC emission intensity is temperature dependent. The maximum sensor sensitivity of the studied phosphor was discovered to be about 1.61%K−1 at the optimum doping concentration. And the phosphor is demonstrated to have high thermal stability by temperature cycling test. Eventually, a green light-emitting diode device was realized by using synthesized particles and a 980 nm near-infrared chip, which can emit a more obvious green light when the voltage reaches 1.80 V and the current can reach 800 mA, thus confirming its applicability in solid-state lighting. And the LED devices have been tested for life stability with little or no light degradation. These properties make the phosphors not only suitable for non-contact optical temperature measurement, but also able to be applied to solid state lighting. [ABSTRACT FROM AUTHOR]

Fluorescence intensity ratio (FIR) thermometry has been regarded as new optical thermometry because of its faster response, higher sensitivity, and accuracy. However, improving the sensitivity is still a challenge. Here, Ba2LuNbO6:Er3+,Yb3+ up‐conversion specimens were synthesized, characterized, and designed for dual‐mode thermometry based on FIR. The 2H11/2/4S3/2 thermally coupled energy levels (TCELs) and 2H11/2/4F9/2 non‐TCELs (NTCELs) of Er3+ were selected as two FIR modes for optical thermometry. The energy gap of 2H11/2/4S3/2 TCELs of Er3+ in Ba2LuNbO6:Er3+,Yb3+ phosphors was confirmed as 977 cm−1. Therefore, the maximal relative sensitivity (Sr) of FIR based on TCELs is 1.53% K−1 @ 303 K. For FIR based on NTCELs, a higher maximal Sr value of 1.81% K−1 @ 303 K is obtained, which surpasses other Er3+‐doped up‐conversion specimens. In addition, the phosphors exhibit excellent thermal fatigue resistance and temperature resolution. Results suggest that Ba2LuNbO6:Er3+,Yb3+ specimens might be applied in the temperature sensing field. [ABSTRACT FROM AUTHOR]

The performance control and multidimensional applications of upconversion phosphor have become the hotspot and difficulty in current research and application due to the complex luminescence mechanism. Based on the efficient Gd2O2S: Er3+ upconversion luminescence of 1550 nm excitation and design strategy for co‐doped materials, the multicolor (light green to red) and multifunctional upconversion phosphor Gd2O2S: Er3+, Ho3+ is successfully prepared. Benefiting from the clear mechanism of three‐photon upconversion and energy transfer after co‐doping, the novel applications of Gd2O2S: Er3+, Ho3+ can greatly be expanded. This phosphor can be well used as a fluorescence thermometer due to the higher sensitivity (2.46% K−1@170 K), wider temperature sensing range (170–267 K, Sr > 1% K−1), and greater color variation (Δx = 0.2416, Δy = 0.2483) relative to Gd2O2S: Er3+ and other same type of material. In addition, multiple patterns and encoded outputs are also effectively achieved by the combination of phosphors under multiple light stimuli response. This shows the greater application potential of phosphor in the fields of anti‐counterfeiting and information encryption. This study can also provide a new view to study the more high‐performance and multifunctional upconversion phosphor. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions The Northern Hemisphere harbours the greatest diversity of temperate plants on Earth, with East Asia having the highest species richness compared with North America and Europe. When and how this uneven diversification pattern emerged remains unclear. Here, we use a conifer genus that forms extensive forests in the Northern Hemisphere to explore a fundamental question in ecology and evolution: what processes underlie temperate biodiversity through time and space?The Northern Hemisphere.Abies.To reconstruct a well‐supported framework for estimating diversification rate, we performed phylogenetic analyses using concatenation and coalescent methods based on 58 fir taxa and 56 nuclear single‐copy genes. Niche evolution was explored using species occurrence data and environmental factors based on the l1ou model. Multiple regression was carried out to identify correlations between species richness and environmental variables at global and regional scales, to evaluate factors of species diversity preference, and potentially to explain the evolutionary history of firs.We identified East Asia as having the highest species diversity and speciation rate. Two clade‐specific niche shifts corresponding with the distribution of firs were detected, one in the Himalaya‐Hengduan Mountains (c. 12.2 Ma) and the other in the Mexican highlands (c. 14.3 Ma), but none in the Euro‐Mediterranean region. Fir species richness increased with cool temperatures both globally and regionally. Seasonal precipitation showed significant positive correlation to species richness on a global scale and in North America and the Euro‐Mediterranean region. Soil factors showed significant trends and moderate correlations with species richness in the Himalaya‐Hengduan Mountains and Mexican highlands.Our results indicate that modern firs prefer cool climates with seasonal rainfall. East Asian firs experienced niche shifts with the Himalayan orogeny in the Middle Miocene. Novel heterogeneous habitats due to changes in topography and the establishment of a monsoon climate, accompanied by niche shift, can account for the high speciation of firs in East Asia. A similar process is found in the Mexican highland firs. In contrast, cold–dry continental climate in North America since the late Paleogene and the lack of seasonal rainfall and relatively stable topography in the Euro‐Mediterranean region are the main limiting factors for fir diversification. Our study rejects the ‘clade age’ hypothesis but supports the hypothesis that niche shift related to high diversification rate triggered by environmental heterogeneity underlies the uneven species diversity of the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

This paper presents the operation of a modified speed controller with a standard PI/PID structure that includes the preprocessing of the controller's input signal, focusing on the past behavior of control errors. The modification involves adding a delay line, with the outputs of the individual line segments summed with a weighting method, as detailed in the paper. One of the significant advantages of this method is its use of a standard industrial controller structure, which makes it highly practical and easily implementable in existing systems. By relying on well-established control frameworks, this approach reduces the need for specialized hardware or complex modifications, allowing for smoother integration and lower implementation costs. The delay-based signal shaping shows excellent properties for the electric drive system powered by a hard-switching PWM converter. The set of weighted delays acts as a filter whose parameters are chosen using the quality function to test different configurations for optimal performance. When tested in a speed control system for a Permanent Magnet Synchronous Motor, the modifications improved the control quality index, indicating better performance and efficiency. Importantly, the system allows for reducing or eliminating the gain in the differentiating part of the controller, which decreases motor current chattering and noise. This paper includes an experimental verification of the proposed solution in a laboratory setting under semi-industrial conditions. [ABSTRACT FROM AUTHOR]

This paper presents a programmable digital filtering unit dedicated to operating with signals from infrared (IR) detection modules. The designed device is quite useful for increasing the signal-to-noise ratio due to the reduction in noise and interference from detector–amplifier circuits or external radiation sources. Moreover, the developed device is flexible due to the possibility of programming the desired filter types and their responses. In the circuit, an advanced field-programmable gate array FPGA chip was used to ensure an adequate number of resources that are necessary to implement an effective filtration process. The proposed circuity was assisted by a 32-bit microcontroller to perform controlling functions and could operate at frequency sampling of up to 40 MSa/s with 16-bit resolution. In addition, in our application, the sampling frequency decimation enabled obtaining relatively narrow passband characteristics also in the low frequency range. The filtered signal was available in real time at the digital-to-analog converter output. In the paper, we showed results of simulations and real measurements of filters implementation in the FPGA device. Moreover, we also presented a practical application of the proposed circuit in cooperation with an InAsSb mid-IR detector module, where its self-noise was effectively reduced. The presented device can be regarded as an attractive alternative to the lock-in technique, artificial intelligence algorithms, or wavelet transform in applications where their use is impossible or problematic. Comparing the presented device with the previous proposal, a higher signal-to-noise ratio improvement and wider bandwidth of operation were obtained. [ABSTRACT FROM AUTHOR]

The 2016 Amsterdam Placental Workshop Group Consensus Statement recommends sampling a block of the placenta close to the umbilical cord insertion site (UCIB) for histopathological evaluation. This piece of placenta at the umbilical cord insertion is presumed to give a better yield of inflammation (if present). We aimed to investigate the utility of the UCIB in the detection of maternal and/or fetal inflammatory responses (MIR and/or FIR), in comparison with the other sections of the placental parenchyma. This is a retrospective cross‐sectional study including all placentas with histologic chorioamnionitis. The histopathological slides of placentas were reviewed as per Amsterdam consensus guidelines. Diagnostic performance of UCIB in identifying MIR and/or FIR, relative to the other placental sections, was assessed. UCIB revealed diagnostic sensitivity, specificity, and diagnostic accuracy of 79.2% (95% CI: 74.2–83.6%), 100.0% (95% CI: 95.6–100.0%), and 83.6% (95% CI: 79.5–87.2%), respectively, in the detection of FIR, while showing a low sensitivity of 52.6% (95% CI: 47.5–57.6%) in detecting MIR. In 59 (24.6%) cases, FIR was not seen in the corresponding placental parenchymal sections but was detected in the UCIBs. This study is the first study to confirm that a section from the UCIB is essential for the detection of FIR, which affirms the Amsterdam consensus sampling recommendations. [ABSTRACT FROM AUTHOR]

Due to its relatively low cost and remote detection characteristics, optical temperature sensing technology based on FIR has received widespread attention. At present, there is a lack of theoretical guidance on how to purposefully improve or guide the development of high-performance temperature sensing materials. Herein, the structure of a novel material K 7 MgSc 2 B 15 O 30 has been confirmed by the XRD analysis. Furthermore, the effect of Zn on the crystal structure and the photoluminescence (PL) properties of K 7 MgSc 2 B 15 O 30 :Mn2+ has been studied. The PL spectra analysis of a series of Mn2+ doped K 7 MgSc 2 B 15 O 30 luminescence materials indicates that two kinds of Mn2+ emitting centers (Mn(1) and Mn(2)) exist due to the two possible substitution sites Mg2+ and Sc3+. With the increasing of Zn2+, the intensity ratio of Mn(2) to Mn(1) improves from 1.01 to 1.88 at room temperature. Especially, the thermal stability of Mn(1) and Mn(2) gradually decrease with the increasing of Zn2+ contents, which can be due to the lengthening of Zn/Mg–O bonds and the lattice distortion of ScO 6 , respectively. Finally, their temperature sensing sensitivity has been enhanced by the doping of Zn2+, which has a close relation to the different effect of the thermal stability of Mn(1) and Mn(2). This work is expected to provide new ideas for the development of high-performance temperature sensing materials based on FIR, and is helpful to understand the relationship between the crystal structure and luminescence properties. • The crystal structure of K 7 MgSc 2 B 15 O 30 has been firstly studied. • Two emitting centers of Mn have been confirmed in K 7 MgSc 2 B 15 O 30 :Mn2+. • The decreased PL thermal stability attributes to the structure modulation. • The relative sensitivity can been tunable by the doping of Zn2+. [ABSTRACT FROM AUTHOR]

In the context of the increasing security issues of cyber‐physical systems (CPSs), this paper addresses the parameter identification of binary observation‐based finite impulse response (FIR) systems under replay attacks, overcoming the problem of high nonlinearity of quantized systems and greater data sparsity caused by replay attacks. For the attacker, based on the energy‐constrained condition, an optimization attack model is established to maximize the absolute error of identification, giving the method of obtaining the optimal attack strategy. Following the defender, the identifiability of unknown parameters is discussed and a robust defense scheme is proposed. This scheme involves a joint identification strategy for both the attack strategy and unknown parameters. By enhancing the excitability of system inputs, consistent identification is ensured despite replay attacks. An algorithm for the accomplishment of the joint identification strategy is presented based on the grid search method. Rationality of the method is confirmed with performing numerical simulations. [ABSTRACT FROM AUTHOR]

Short line segment toolpaths widely used in five-axis CNC machine tools has the defects of low-order continuity, the tangential and curvature discontinuities at the corners, which result in frequent fluctuation of feedrate, thus degrading the machining quality and efficiency. Therefore, smoothing interpolation of the path becomes significant. Although the local corner smoothing methods are relative mature, the global smoothing methods can hardly be fulfilled in real time, because either the replacing of line segments by global smooth curves or the scheduling of five-axis feedrate requires time-consuming iterative or pre-processed computing. To deal with above problem, this paper proposes a real-time global smoothing and interpolation method for five-axis short line segment toolpaths. This is realized by a G0-G1-C2 two layered fairing method, containing a G0-G1 outer-layer smoothing step and a G1-C2 inner-layer smoothing step. In the outer layer, a piecewise dual B-spline with globally G1 continuity is constructed for replacing the G0 continuous line-segment toolpath. Further, in the inner layer, a FIR (Finite Impulse Response) convolving algorithm is presented for generating C2-continuous axial trajectories with bounded acceleration and jerk, according to the G1 dual-spline path. Both of the two layers are lightweight in computation, which makes the proposed global smoothing method have strong real-time capability. Verification and comparison tests demonstrate that the proposed method performs similarly with existing off-line methods in smoothing results, but performs overwhelmingly in real-time capability, and its single-step computation calls for merely about 12 % of the total interpolation period. • Presents a G0-G1-C2 two layered fairing method for real-time global smoothing of five-axis toolpaths. • In the G0-G1 outer layer, G0 path is smoothed as a piecewise dual B-spline with globally G1 continuity. • In the G1-C2 inner layer, the G1 path is smoothed as a C1 trajectory by a FIR convolving algorithm. [ABSTRACT FROM AUTHOR]

Far-Infrared Radiation (FIR) is emerging as a novel non-invasive tool for mitigating inflammation and oxidative stress, offering potential benefits for certain medical conditions such as cardiovascular disease and chronic inflammatory disorders. We previously demonstrated that the application of patch-based FIR therapy on human umbilical vein endothelial cells (HUVECs) reduced the expression of inflammatory biomarkers and the levels of reactive oxygen species (ROS). Several in vitro studies have shown the inhibitory effects of FIR therapy on cell growth in different cancer cells (including murine melanoma cells), mainly using the wound healing assay, without direct cell motility or tracking analysis. The main objective of the present study was to conduct an in-depth analysis of single-cell motility and tracking during the wound healing assay, using an innovative high-throughput technique in the human melanoma cell line M14/C2. This technique evaluates various motility descriptors, such as average velocity, average curvature, average turning angle, and diffusion coefficient. Our results demonstrated that patch-based FIR therapy did not impact cell proliferation and viability or the activation of mitogen-activated protein kinases (MAPKs) in the human melanoma cell line M14/C2. Moreover, no significant differences in cell motility and tracking were observed between control cells and patch-treated cells. Altogether, these findings confirm the beneficial effects of the in vitro application of patch-based FIR therapy in human melanoma cell lines, although such effects need to be confirmed in future in vivo studies.

Abstract This article introduces a novel FIR filter using a Radix-2r multiplier combined with 4:2 and 3:2 compressors for denoising Electrooculography (EOG) signals. This approach replaces traditional ripple-carry adders with compressors to add the partial products generated by the Radix-2r multiplier, resulting in reduced delay and energy consumption. The FIR filter is implemented in gate-level Verilog HDL, verified using ModelSim and Altera DSP Builder, and synthesized with the Cadence RTL compiler. Compared to conventional designs, the proposed filter achieves a 71.48% reduction in area, 73.28% reduction in power, 51.84% reduction in delay, 86.22% reduction in the area-delay product (ADP), and 92.38% reduction in energy-per-operation (EPS), significantly outperforming the SOPOT filter.

Medical signal processing requires noise and interference-free inputs for precise segregation and classification operations. However, sensing and transmitting wireless media/devices generate noise that results in signal tampering in feature extractions. To address these issues, this article introduces a finite impulse response design based on a two-level transpose Vedic multiplier. The proposed architecture identifies the zero-noise impulse across the varying sensing intervals. In this process, the first level is the process of transpose array operations with equalization implemented to achieve zero noise at any sensed interval. This transpose occurs between successive array representations of the input with continuity. If the continuity is unavailable, then the noise interruption is considerable and results in signal tampering. The second level of the Vedic multiplier is to optimize the transpose speed for zero-noise segregation. This is performed independently for the zero- and nonzero-noise intervals. Finally, the finite impulse response is estimated as the sum of zero- and nonzero-noise inputs at any finite classification.

Supplement 1S. ASupplement 1S. B Supplement 1S. C Supplement 1S. D Fluorescence intensity ratio ( FIR) =( 46.83%+ 12.66%) / 15.07% = 3.95 Supplement 1S. E Fluorescence intensity ratio ( FIR) =( 31.55%+ 20.76% + 18.16)/ 13.78% = 5.11 Supplement 1S. F Fluorescence intensity ratio ( FIR) =( 34.46%+ 18.82%) / 17.87% = 2.98 Supplement 1S. G Fluorescence intensity ratio ( FIR) =( 8.15%+ 23.18%)/ 25.38% = 1.23 Supplement 1S. H Fluorescence intensity ratio ( FIR) = 20.76%/ 26.36% = 0.79 [Extracted from the article]

Abies nephrolepis Nature Reserve has complex habitats and rich species diversity but lacks systematic ecological surveys. We focused on Orchid in Abies nephrolepis Nature Reserve, investigated and analyzed Orchid diversity and changes in community structure according to the characteristics of the alpine valleys in the study area, in terms of altitude gradient and habitat type, using the sample line method and the quadrat method. The results showed that 11 genera and 13 species of Orchidaceae were found in the survey, among which the species richness of Malaxis monophyllos was the highest, Neottia puberula was the second highest, and the species richness of Tulotis ussuriensis was the lowest, and the species with relative plurality ≥ 10% were Malaxis monophyllos (51.69%), Neottia puberula (14.77%), and Cypripedium guttatum (11.15%). The results of diversity analysis showed that Orchidaceae species were rich and the diversity index were the highest in the middle altitude area of 1950–2250 m; the distribution of Orchidaceae in the low altitude area was obviously clustered, and the similarity with the high altitude area was low. With the increase in altitude, the number of species showed an increase and then a decrease, showing a single‐peak state, which was in line with the theory of "Intermediate altitude expansion hypothesis". The species and number of Orchidaceae in different habitats of Abies nephrolepis Nature Reserve also varied considerably, with Shannon‐Wiener diversity index being the highest in EV4 (Abies nephrolepis + Picea meyeri + Picea wilsonii + Larix gmelinii var. principis‐rupprechtii—Lonicera hispida—Carex lanceolata community) and EV5, and the smallest in EV1 habitats, Pielow evenness index being the highest in EV5 habitats and the lowest in EV1 habitats, and Simpson's index being the highest in EV5 habitats and the lowest in EV1 habitats. This study provides a scientific basis for strengthening regional monitoring of species diversity and protecting biodiversity. [ABSTRACT FROM AUTHOR]

Designing high-performance integrated circuits that balance area, speed, and power is increasingly challenging. This study optimises hardware implementation of FIR filters using an innovative Amalgam Multiplier, minimising resource use without compromising performance. The key challenge in designing signal processing hardware is the multiplier design, which significantly affects efficiency. This study explores integrated circuit optimisation, addressing the delicate balance between area utilisation, speed, and power consumption. Focusing on hardware implementation of Finite Impulse Response (FIR) filters in signal processing, the article starts with a conventional FIR filter design using a standard array multiplier which consumed 1.790 W, with 8 s real-time completion. Then, Linear Phase FIR (LP-FIR) filter is designed using Braun and Dadda Multiplier. LP-FIR filter with Braun multiplier consumed 1.436 W power and 26 s of completion time whereas LP-FIR with Dadda multiplier consumed 1.363 W power and 23 s of completion time. Finally, the implementation of novel LP-FIR enhanced by Amalgam multiplier consumed 0.302 W power and 10.29 s of completion time, marking a significant advancement in integrated circuit design. [ABSTRACT FROM AUTHOR]

As one of the fundamental physical quantities, temperature is extremely important in various fields. In order to study the temperature sensing characteristics of dual‐emitting center phosphors, Bi3+‐doped and Bi3+/Sm3+‐doped Sr2Ga2GeO7 phosphors were synthesized by high‐temperature solid‐phase method. Under 312 nm excitation, the Sr2Ga2GeO7:Bi3+ phosphor exhibits a blue broadband emission corresponding to the 3P1 → 1S0 transition of Bi3+ ions. By testing the temperature change spectrum of phosphors, it was found that Bi3+ exhibited strong thermal sensitivity. However, due to the fact that single ion doped phosphors are easily affected by other factors when applied to the field of temperature sensing, based on the thermal sensitivity of Bi3+, Sm3+ with low temperature sensitivity was selected as the co‐doped ion, and it was found that the two ions had different thermal quenching characteristics when the temperature change spectrum was tested. Using the temperature detection method based on the fluorescence intensity ratio (FIR) of the dual emission centers, it was found that the best absolute sensitivity Sa was 3.125% K−1 and the maximum relative sensitivity Sr was 1.275% K−1 in the range of 303–423 K. These results show that Sr2Ga2GeO7:Bi3+/Sm3+ phosphors have broad application prospects in the field of optical temperature sensing. [ABSTRACT FROM AUTHOR]

Insect infestation triggers multiple defense responses in plants, both locally at the infection site and systemically throughout the plant, including the production of feeding deterrents, toxins, defensive proteins, enzymes, and secondary metabolites. Our study aimed to compare the endogenous levels of antioxidative enzymes, photosynthetic pigments, phytohormones, total phenols, and flavonoids in bark-beetle-infested and uninfested trees. We evaluated the surviving trees in bark-beetle-infested stands, assessing both the condition and defense of uninfested and infested beech (Fagus sylvatica), pine (Pinus sylvestris), and fir (Abies alba) trees. Sampling was performed at six affected sites in the Czech Republic, targeting trees that were resilient to significant health deterioration caused by abiotic and biotic factors. The results showed different levels of most of the measured compounds in the three species. Among all the tested species, photosynthetic pigment levels showed the strongest association with infestation status, which was generally lower in the infested plants. For chlorophyll a, extremely significant reductions were observed from 123 ± 20.6 to 101 ± 17.9 μg/g dry weight (DW) in pine, from 231 ± 33.1 to 199 ± 22.2 μg/g DW in beech, and from 60 ± 5.66 to 51.3 ± 6.27 μg/g DW in fir. In contrast, enzymatic activities indicated only isolated instances of significant association, whereas antioxidative properties (total phenolic content, flavonoids, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity) were not significantly associated with infestation status. There was a statistically significant increase in glutathione reductase activity in infested fir and pine trees. However, this difference was not statistically significant in beech. In contrast, a significant increase in superoxide dismutase activity was detected in infected beech trees. Phytohormones have emerged as the most diverse group of analyzed compounds. Cytokinins were the most distinct, with many of them being significantly increased in infested pines, whereas both beech and fir showed only one significant association. Additionally, derivatives of jasmonic acid also showed a distinct pattern of change associated with bark beetle infestation, with the levels of three out of the four analyzed jasmonates being significantly decreased in infested pines, whereas no effects were observed in beeches and firs. Notably, many phytohormones were significantly elevated in the infested pine, whereas both beech and fir exhibited only one significant association. Overall, the data showed that pines responded differently to bark beetles than to beeches or firs. The greatest changes in phytohormones were observed in pine, whereas the most significant changes in photosynthetic pigments were observed in beech and fir trees. [ABSTRACT FROM AUTHOR]

This article introduces a novel FIR filter using a Radix-2r multiplier combined with 4:2 and 3:2 compressors for denoising Electrooculography (EOG) signals. This approach replaces traditional ripple-carry adders with compressors to add the partial products generated by the Radix-2r multiplier, resulting in reduced delay and energy consumption. The FIR filter is implemented in gate-level Verilog HDL, verified using ModelSim and Altera DSP Builder, and synthesized with the Cadence RTL compiler. Compared to conventional designs, the proposed filter achieves a 71.48% reduction in area, 73.28% reduction in power, 51.84% reduction in delay, 86.22% reduction in the area-delay product (ADP), and 92.38% reduction in energy-per-operation (EPS), significantly outperforming the SOPOT filter. [ABSTRACT FROM AUTHOR]

The paper considers the problem of nonparametric estimation of nonlinear characteristic in the FIR Wiener system. Methods proposed so far have suffered from the so-called 'curse of dimensionality' and their practical applications have been limited to the very short impulse responses of the linear component. In the proposed approach, the class of (stochastically initialised) repeated exponential input excitations is introduced, and a modified kernel-based estimator is presented. It is shown that the rate of convergence to the genuine system characteristic is significantly improved and does not depend on the length of the impulse response of the linear dynamic block. [ABSTRACT FROM AUTHOR]

Understanding the response of forests to the increases in atmospheric CO2 (ca) is fundamental to implementing innovative management strategies and for assessing impacts on the global carbon and water cycles. Here, we explored correlations between ecophysiological traits and climate variability that influence changes in stable isotope carbon and oxygen (δ13C and δ18O) of tree‐rings. We present these relationships between species of the contrasting genera Abies and Pinus, along a latitudinal transect encompassing different biogeographical regions in North America. We also tested if the rate of intrinsic water‐use efficiency per unit of ca (dW/dca) during two periods (1890–1965 vs. 1966–2016), for fir and pine were different and indicated acclimation to ca increases. We hypothesize that, spatially and temporally, the divergent responses among species to carbon and oxygen isotopes and dW/dca are influenced by the site conditions and the historical increases in ca. From our results, we show that fir and pine species will behave physiologically different as global warming progresses. Firs are more responsive to atmosphere vapor pressure deficit along different geographical zones. The survival of forests species under climate change will rely on the response to water stress and species' traits that influence the regulation of dW. Finally, we want to highlight the concept of "progressive resource limitation" of soil water and nutrients, previously proposed by other authors, that likely indicate fir species that inhabit moister sites will benefit more from increased ca than pine, but this positive effect is likely transitory as global warming increases. Plain Language Summary: The response of forests to increased atmospheric CO2, is dependent on how tree species cope with water stress. We explored tree species response to water stress by examining the correlation between tree‐ring growth and climatic variables. We focused on the tree genera Abies (fir) and Pinus (pine), along a latitudinal transect encompassing different biogeographical regions. We examined how fir and pine trees optimize water use as atmospheric CO2 increased during two distinct periods (1890–1965 vs. 1966–2016). We hypothesized that the interactions between species and site conditions dictate the sensitivity to increases in atmospheric CO2. We found fir trees are more sensitive to changes in humidity and atmospheric CO2, suggesting there is a threshold where increased stress will occur in these trees as climate changes. In the future, forest stability and productivity under changing climate is dependent on how trees adjust to water stress. We want to highlight the concept of "progressive resource limitation" of soil water and nutrients that show fir species in moister sites will benefit more from increased CO2 than pine, but this effect will diminish as global warming becomes more acute. Key Points: Rates of (intrinsic water use efficiency) per ca unit, are species and site conditions dependentFir and pine species are behaving physiologically different as global warming progressesFir species could benefit more from increases in CO2 as long as water is not limited [ABSTRACT FROM AUTHOR]

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Aim: Pinaceae have been noted for their tendency towards reticulation as a result of interspecific hybridization. Here, we demonstrated the phylogeographic dynamics of the native Northeast Asian sub‐alpine conifer, Abies nephrolepis species complex (ANSC), evolving in circular overlaps along the Northeast Asian landform, which functions as a corridor with the sea, thus acting as a geographic barrier. Location: Northeast Asia: the Korean Peninsula, Japanese Archipelago, Russian Far East and northeastern China. Taxon: Abies nephrolepis species complex (Family Pinaceae, Genus Abies, Section Balsamea, Abies nephrolepis, A. koreana, A. veitchii and A. sachalinensis). Methods: A total of 728 individuals from 38 ANSC populations were analysed using multiplexed inter‐simple sequence repeat genotyping by sequencing to capture variations in biparental nuclear genomes. Eight mitochondrial regions and eight chloroplast regions of each individual were sequenced using the MiSeq platform and Sanger sequencing. Species distribution models were generated. Results: Bayesian clustering with 507 nuclear single nucleotide polymorphisms and the discrepancy between cytoplasmic and nuclear genome lineages implied contemporary and ancient connections between neighbouring species in the form of circular overlap. This genetic connectivity was supported by principal component analysis. Strong correlations between genetic distance and geographic distance were observed, suggesting that gene flow occurs through a continuous chain around the sea. We also found that gene flow direction and intensity changed over time, with support from palaeodistribution modelling. Conclusion: Past hybridization events were captured in cytoplasmic genomes, generating heterogeneity across maternal ancestries. This intensive phylogeographic study demonstrates speciation with incomplete reproductive isolation (continuous gene flow) among neighbouring species with an alteration of the direction and intensity of gene flow due to climate change. The divergence of ANSC due to repeated isolation and reconnection caused by heterogenous physiological environments and climate fluctuation provides a model to solve evolutionary scenarios for reticulate evolution in Pinaceae and other plants. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to explore the differences in cervical degeneration between healthy people with and without cervical flexion-relaxation phenomenon (FRP) and to identify whether the disappearance of cervical FRP is related to cervical degeneration. Methods: According to the flexion relaxation ratio (FRR), healthy subjects were divided into the normal FRP group and the abnormal FRP group. Besides, MRI was used to evaluate the degeneration of the passive subsystem (vertebral body, intervertebral disc, cervical sagittal balance, etc.) and the active subsystem (deep flexors [DEs], deep extensors [DFs], and superficial extensors [SEs]). In addition, the correlation of the FRR with the cervical degeneration score, C2-7Cobb, Borden method, relative total cross-sectional area (rTCSA), relative functional cross-sectional area (rFCSA), and fatty infiltration ratio (FIR) was analyzed. Results: A total of 128 healthy subjects were divided into the normal FRP group (n=52, 40.63%) and the abnormal FRP group (n=76, 59.38%). There were significant differences between the normal FRP group and the abnormal FRP group in the cervical degeneration score (z=-6.819, P<0.001), C2-7Cobb (t=2.994, P=0.004), Borden method (t=2.811, P=0.006), and FIR of DEs (t=-4.322, P<0.001). The FRR was significantly correlated with the cervical degeneration score (r=-0.457, P<0.001), C2-7Cobb (r=0.228, P=0.010), Borden method (r=0.197, P=0.026), and FIR of DEs (r=-0.253, P=0.004). Conclusion: The disappearance of cervical FRP is related to cervical degeneration. A new hypothesis mechanism for FRP is proposed. The cervical FRP test is an effective and noninvasive examination for the differential diagnosis of healthy people, people with potential NSNP, and patients with NSNP. [ABSTRACT FROM AUTHOR]

In recent years, with the increasing demand for non-contact temperature measurement, it is urgent to develop a new type of phosphor with double emission centers, high sensitivity and good reliability. A series of Bi3+and Eu3+ co-doped La 2 LiSbO 6 double emission center phosphors were successfully prepared. The response characteristics of Bi3+and Eu3+ at different temperatures in the range of 293–473k were calculated by fluorescence intensity ratio (FIR) technique. The optimal relative sensitivity S r and absolute sensitivity S a were 1.13 % K−1 and 1.27 % K−1, respectively. Hence, La 2 LiSbO 6 :Bi3+, Eu3+ phosphors have the capability of non-contact optical temperature measurement and are a promising material for application. The phosphor is combined with the optical fiber temperature sensor to monitor the real-time temperature of the computer central processing unit. The optical fiber temperature sensor system breaks through the limitations of traditional temperature measurement, and can be used in special environments such as small size and strong electromagnetic interference. It has become an ideal choice to replace the traditional temperature sensor. [ABSTRACT FROM AUTHOR]

Medical signal processing requires noise and interference‐free inputs for precise segregation and classification operations. However, sensing and transmitting wireless media/devices generate noise that results in signal tampering in feature extractions. To address these issues, this article introduces a finite impulse response design based on a two‐level transpose Vedic multiplier. The proposed architecture identifies the zero‐noise impulse across the varying sensing intervals. In this process, the first level is the process of transpose array operations with equalization implemented to achieve zero noise at any sensed interval. This transpose occurs between successive array representations of the input with continuity. If the continuity is unavailable, then the noise interruption is considerable and results in signal tampering. The second level of the Vedic multiplier is to optimize the transpose speed for zero‐noise segregation. This is performed independently for the zero‐ and nonzero‐noise intervals. Finally, the finite impulse response is estimated as the sum of zero‐ and nonzero‐noise inputs at any finite classification. [ABSTRACT FROM AUTHOR]

Tree-ring blue intensity (BI) has the potential to provide information on past summer temperatures of a similar quality to that of tree-ring maximum latewood density and at a substantially reduced cost. To explore the applicability of BI in subtropical regions, the inverted BI for the earlywood, latewood, and the delta BI (DBI) parameters, together with tree-ring width of subalpine fir (Abies fargesii Franch.) in the Shennongjia area of China, were measured, and the corresponding chronologies were developed. The relationships between these chronologies and monthly precipitation, monthly mean minimum temperature, monthly mean temperature, and monthly mean maximum temperature were explored through correlation analysis. Results show that the DBI chronology is closely related to the temperature in August of the current year, indicating that BI, specifically delta BI, data are suitable for use in dendroclimatology studies in subtropical areas. The resultant mean temperature reconstruction for August, based on DBI, explains 40.8% of the temperature variance and is robustly validated using independent periods from the calibration. This pilot study not only highlights the potential of DBI for temperature reconstruction in China but also offers valuable insights into historical climate variations in the Shennongjia region. Moreover, it shows the potential for utilizing such tree-ring data from low-latitude regions to derive past climate data in subtropical warm-humid zones. [ABSTRACT FROM AUTHOR]

Abies nebrodensis is a species of fir endemic to Sicily, represented by only 30 trees in the natural population and is currently classified as critically endangered by IUCN. In such context, monitoring its health status is essential for the proper management and preservation of this species. Phytosanitary surveys of trees of the natural population of A. nebrodensis and on potted plants raised in the local forest nursery were carried out, and the phyllosphere fungal community was investigated. The health condition of trees in the natural population were fairly good, with needle reddening and blight as the most frequently observed symptoms on the foliage, while in the nursery similar disorders were registered on about the 1.3% of potted plants. Results on fungal isolations highlighted the presence of species belonging to Valsa, Cytospora (which includes anamorphs of Valsa) and Rhizosphaera genera as the most represented on both reddened and green needles; these results suggest that these fungi likely live as endophytes, resuming their growth when needles are affected by environmental stressors such as wind, hail, mechanical wounds and do not represent a biotic constraint for A. nebrodensis. The disorders observed appear mostly as a consequence of the harsh site in which the relic species lives. Together with the fungal community observed on symptomatic and healthy needles, they indicate that A. nebrodensis adapted and tolerates its altered habitat. [ABSTRACT FROM AUTHOR]

Ascomycete fungi isolated in Central Siberia from canker lesions of Abies sibirica Ledeb. were assigned to the genus Corinectria Gonzalez & Chaverri. Our earlier research has shown four Corinectria Siberian strains to be significantly different genetically from the known Corinectria spp. This work investigated the secondary metabolites of 23 morphologically similar Corinectria Siberian strains and their phytotoxicity. The strains were divided into two types by their morphological and cultural traits, MCT1 and MCT2. The MCT1 strains synthesized the meroterpenoids ilicicolins A and B, ilicicolin A epoxide and chlorocylindrocarpol; the MCT2 strains produced ilicicolins C, D (ascochlorin), F and ascofuranol. The phytotoxicity of the Corinectria strains showed a significant heterogeneity to Picea obovata seeds and was exhibited by 31% of the MCT1 strains and 50% of the МСТ2 strains. The more phytotoxic strains had an inhibitory effect on A. sibirica calluses. Ilicicolins C, D, and F synthesized by the MCT2 strains significantly inhibited the growth processes of both A. sibirica seedlings and Pinus sibirica Du Tour saplings. [ABSTRACT FROM AUTHOR]

The forest loss and degradation caused by tree heart rot presents an increasingly challenging issue for the protection and utilization of forest resources. Yet, it is questionable whether heartwood-decayed trees can still function on par with healthy trees. Here, using tree ring data, we established basal area increment (BAI) series of healthy and heartwood-decayed fir trees at four sites (Abies spectabilis in Bomi; A. georgei Orr in Deqin as well as the Sygera Mountain; A. fabri Craib in Yajiageng) in the southeastern Qinghai-Tibetan Plateau (QTP). We conducted a comparative analysis of the difference in the BAI, response to climate factors and elasticity under environmental stress between the healthy and decayed fir. The results show that, in QTP, fir susceptibility to decay is uncorrelated with growth rates. However, after decaying occurs in fir trees, their radial growth is restricted in warm and humid areas (i.e., at Bomi and Yajiageng). The average BAI of healthy fir is 70.32 % and 86.32 % higher than that of decayed fir in Bomi and Yajiageng respectively (p 0.05). Moreover, healthy fir exhibits a more pronounced response to climatic conditions. Almost all BAI series of healthy and decayed fir in the southeastern QTP is positively correlated with the temperature and vapor pressure deficit. Under temperature stress, decayed fir trees are less resistant at three sites. This empirical study supports that there is no correlation between conifer trees’ radial growth rate and their likelihood of heartwood decay, and provides a compelling explanation for the constrained growth of decayed fir trees. Our findings can bolster the accurate assessment of carbon sinks and the conservation of forest resources in regions prone to high-decaying risks.

We present a theoretical study of the optical absorption coefficient Urbach tail broadening parameter Γ behavior in the Hg1−xCdxTe alloy semiconductor in the 0.21 ≤ x ≤ 0.6 alloy composition interval. This x interval corresponds to the very attractive 0.10 ≤ EG≤ 0.75 eV medium infrared (MIR) and far infrared (FIR) optical ranges. We compare two absorption coefficient nonparabolic models based on Kane 4-band formalism, one including the Burstein–Moss shift called the NPBM-model and the other one without and called the NP-model. By comparing the results of both models with existing experimental and theoretical data, we show the strong nonparabolic behavior of the absorption coefficient in Hg1−xCdxTe in agreement with previous studies. The best fitting is obtained with the NPBM-model, where Γ is used as an adjustable parameter varying with x, temperature (T), and photon energy (ħω) in the E ≤ EG sub-bandgap energy range. With decreasing x, Γ is found to increase first slightly with x in the 0.443 ≤ x ≤ 0.6 MIR range and then strongly and nonlinearly in the 0.21 ≤ x < 0.443 FIR range. These unusual Γ(x, ħω) dependences suggest a strong influence of nonparabolicity and band state mixing effects, which become strongly enhanced in the FIR range between strongly interacting and almost overlapping bands as x tends to 0.16 of the critical value, making Hg1−xCdxTe experience a semiconductor–semimetal transition. [ABSTRACT FROM AUTHOR]

Girdling is often used as an experimental method to study source/sink controls of cambial growth. However, the phloem responses to girdling have not been well investigated. The aim of this research was to characterize the anatomical changes in the phloem and xylem of different species following trunk girdling. Different species of gymnosperm (Abies sibirica, Pinus sylvestris) and angiosperm (Alnus incana, Populus tremula) woody plants were selected. We girdled trunks during active growth and sampled tissues at two levels (1 cm and 35 cm) above the girdle at the end of the growing season. General responses to girdling were recorded for the studied species, such as increased phloem increments, parenchymatization of conducting tissues, reduction in the size of conducting elements, and an increase in the size of axial parenchyma cells in the phloem and xylem. We observed the suppression of xylogenesis in 3 out of 4 species. Differences in the structure of conducting tissues were found, which are due to species differences in the initial tissue structure. In gymnosperms, noticeable differences in the number of resin ducts in the xylem were observed between control and girdled trees. In angiosperms, we found the formation of cells with thickened cell walls in girdled trees (i.e., the formation of phloem and xylem fibers with thickened cell walls in aspen and sclereids in the phloem of alder). Based on the literature data, the observed responses may be due to both the wounding effect and the influence of the high sugar content above the girdle. [ABSTRACT FROM AUTHOR]

Two leafy liverwort species from the late Eocene Rovno amber are described. They are placed in the extant genus Nipponolejeunea (Jubulaceae, Porellales, Marchantiophyta) that includes two extant East Asian species and one fossil species described from the Eocene Baltic amber. New fossil species N. rovnoi sp. nov. and N. solodovnikovii sp. nov. differ from the Baltic N. europea, thus making the extinct diversity of the genus exceeding the contemporary species diversity, and such a case is registered for the first time for liverworts. The finding of Nipponolejeunea in Rovno amber may indicate the presence of Abies in the Eocene of Ukraine, since at the southern border of its distribution in Japan extant species the genus grows only on fir trunk. This is in a good concordance with the recent finding in Rovno amber the longhorn beetle Poliaenus europaeus, also associated with fir trees. [ABSTRACT FROM AUTHOR]

Thirty-four species of lichens and two species of lichenicolous fungi are reported for the first time from Ukraine, specifically from primeval Carpathian forests. Six genera, Absconditonia, Andreiomyces, Chicitaea, Elixia, Puttea, and Sporodophoron, are new to Ukraine. The identification of the species Absconditonia sublignicola, Buellia dives, Cliostomum haematommatis, Lecidella albida, Micarea flavoleprosa, M. isidioprasina, Mycoporum antecellens, Puttea exsequens, Rinodina willeyi, and Sporodophoron cretaceum was confirmed by DNA barcoding. The species Andreiomyces obtusaticus, Chicitaea cristinae, Cliostomum haematommatis, Lecidella albida, Lepra multipuncta, Micarea fallax, M. flavoleprosa, and Ochrolechia bahusiensis were identified using TLC. Additionally, Sporodophoron cretaceum is for the first time reported including fruitbodies. The globally rare epibryophytic species Gyalidea cylindrica is reported from the third locality in the world. [ABSTRACT FROM AUTHOR]

Endophytes play an important role in plant development, survival, and establishment, but their temporal dynamics in young conifer plants are still largely unknown. In this study, the bacterial community was determined by metabarcoding of the 16S rRNA gene in the rhizoplane, roots, and aerial parts of 1- and 5-month-old seedlings of natural populations of Abies religiosa (Kunth) Schltdl. & Cham. In 1-month-old seedlings, Pseudomonas dominated aerial parts (relative abundance 71.6%) and roots (37.9%). However, the roots exhibited significantly higher bacterial species richness than the aerial parts, with the dissimilarity between these plant sections mostly explained by the loss of bacterial amplification sequence variants. After 5 months, Mucilaginibacter dominated in the rhizoplane (9.0%), Streptomyces in the roots (12.2%), and Pseudomonas in the aerial parts (18.1%). The bacterial richness and community structure differed significantly between the plant sections, and these variations were explained mostly by 1-for-1 substitution. The relative abundance of putative metabolic pathways significantly differed between the plant sections at both 1 and 5 months. All the dominant bacterial genera (e.g., Pseudomonas and Burkholderia-Caballeronia-Paraburkholderia) have been reported to have plant growth-promoting capacities and/or antagonism against pathogens, but what defines their role for plant development has still to be determined. This investigation improves our understanding of the early plant-bacteria interactions essential for natural regeneration of A. religiosa forest. [ABSTRACT FROM AUTHOR]

Background: Soil microbial community composition with stand development may be changed due to the variations in canopy structure, understory vegetation, root traits, edaphic conditions, and litter inputs. However, it is still uncertain to what extent these biotic and abiotic factors shape the soil microbial community composition in Chinese fir (Cunninghamia lanceolata) plantations, which are widely planted in southern China. Methods: Amplicon sequencing was used to analyze the diversity and composition of soil bacterial and fungal communities at two soil depths across four developmental stages of Chinese fir plantations. Results: Both the bacterial and fungal communities were significantly different between stand age groups. As stand aged, oligotrophic bacteria decreased in abundance while copiotrophic bacteria increased. Meanwhile, fungal functional groups connected to plants decreased in abundance while that of saprotrophic fungi significantly increased. The variance in bacterial community was mainly attributed to soil variables regarding carbon and nutrient availability, whereas the greatest fraction of fungal community dissimilarity was determined by plant-specific factors such as aboveground stand structure and tree root traits. The chemical composition of litter had a major effect on the soil fungal community, whereas the litter traits had no effect on the bacterial community. Conclusions: The potential drivers of soil fungi and bacteria differ in Chinese fir plantations. By accounting for the impacts of various environmental components, it is possible to anticipate the response of soil bacterial and fungal assemblages to forest management regime implemented in Chinese fir plantations. [ABSTRACT FROM AUTHOR]

The genus Abies is widely distributed across the world and is of high importance for forestry. Since chloroplasts are usually uniparentally inherited, they are an important tool for specific scientific issues like gene flow, parentage, migration and, in general, evolutionary analysis. Established genetic markers for organelles in conifers are rather limited to RFLP markers, which are more labour and time intensive, compared with SSR markers. Using QUIAGEN CLC Workbench 23.03, we aligned two chloroplast genomes from different Abies species (NCBI accessions: NC_039581, NC_042778, NC_039582, NC_042410, NC_035067, NC_062889, NC_042775, NC_057314, NC_041464, MH706706, MH047653 and MH510244) to identify potential SSR candidates. Further selection and development of forward and reverse primers was performed using the NCBI Primer Blast Server application. In this article, we introduce a remarkably polymorphic SSR marker set for various Abies species, which can be useful for other conifer genera, such as Cedrus, Pinus, Pseudotsuga or Picea. In total, 17 cpSSRs showed reliable amplification and polymorphisms in A. grandis with a total of 68 haplotypes detected. All 17 cpSSRs amplified in the tested Abies spp. In the other tested species, except for Taxus baccata, at least one primer was polymorphic. [ABSTRACT FROM AUTHOR]

The combined approaches between ex situ and in situ conservation are of great importance for threatened species in urgent need of protection. This study aims to develop concrete actions to preserve the relic of 30 adult trees of the Sicilian fir (Abies nebrodensis) from extinction using long-term germplasm conservation in liquid nitrogen (LN, −196 °C). Pollen grains were collected, and their moisture content (MC) was measured. Then, viability (2,3,5-tryphenyl tetrazolium chloride, TTC), in vitro germinability, and enzymatic antioxidant activity (ascorbate peroxidase, APX; catalase, CAT) were evaluated before and after cryopreservation. Seeds collected from mature cones underwent X-ray analysis, and only full seeds were used to excise the zygotic embryos (ZEs) for cryopreservation. The MC percentage of ZEs was determined, and then they were plunged in LN with (+PVS2) or without (−PVS2) Plant Vitrification Solution 2; untreated ZEs were used as a control. Viability (TTC test) and in vitro germination were assessed for all ZEs (+PVS2, −PVS2, and control). Embryogenic callus (EC) lines obtained from mature ZEs were cryopreserved applying the 'encapsulation-dehydration' technique. This study has allowed, after optimizing cryopreservation protocols for pollen, ZEs, and EC of A. nebrodensis, to establish the first cryobank of this endangered species in Polizzi Generosa (Palermo, Italy), inside the 'Madonie Regional Park'. The strategy developed for Sicilian fir conservation will pave the way for similar initiatives for other critically endangered conifer species. [ABSTRACT FROM AUTHOR]

The impact of climates on the radial growth of muti-species remains insufficiently understood in the climate-sensitive southeastern Tibetan Plateau, and this hampers an effective assessment of forest growth under the background of global warming. Here, we studied the growth–climate relationships of three major species (Abies georgei, Larix potaninii, and Picea likiangensis) on the Baima Snow Mountain (BSM) by using dendrochronology methods. We constructed basal area increment (BAI) residual chronologies based on the dated ring-width measurements and correlated the chronologies with four climate factors. We also calculated the contributions of each climate factor to species growth. We found that photothermal conditions played a more important role than moisture in modulating radial growth, and P. likiangensi presented the strongest sensitivity to climate change among the three species. The growing season (June and July) temperature positively affected the radial growth of three species. Winter (previous December and current January) SD negatively impacted the tree growth of A. georgei and P. likiangensis. Significant correlations between growth and precipitation were detected only in A. georgei (January and May). Warming since the beginning of the 1950s promoted the growth of A. georgei and P. likiangensis, while the same effect on L. potaninii growth was found in the recent 50 years. [ABSTRACT FROM AUTHOR]

A weak circumferential resolution of defects in the corner part of engineering components brings great challenges to quantitative non-destructive testing. Especially for the corner of carbon fiber reinforced plastics (CFRP), the complex wave propagation behaviors caused by the elastic anisotropy, laminate structure, and curved surface make the information of defects hard to be distinguished, which finally results in a poor imaging resolution. The surface adaptive ultrasonic (SAUL) method for CFRP corner is investigated, and an improved strategy, focusing in receiving (FiR) of SAUL signals is proposed here. With an isotropic plexiglass as a comparison, the effectiveness of FiR is verified by finite element simulations and experiments. The elastic properties of CFRP corner are accurately characterized and a finite element model is established. On this basis, the wave propagation behavior in the corner is studied, and the influence of the water distance h on the maximum amplitude (MAD) and signal-to-noise ratio (SNR) at the defect is analyzed. The results show that the structural noise can be eliminated, and the imaging quality and SNR can be improved by optimizing the h. After FiR, the maximum increase of defect amplitude is about 9.5 dB and 13.2 dB for plexiglass and CFRP, respectively. Meanwhile, the maximum relative error in length is reduced by 16.7% in plexiglass, and by 13.4% for the 3-mm delamination in CFRP. The strategy would be promising to improve the detection quality of the corner in curved components. [ABSTRACT FROM AUTHOR]

Energy deprivation triggers various physiological, biochemical and molecular changes in plants under abiotic stress. We investigated the oxidative damages in the high altitude grown conifer Korean fir (Abies koreana) exposed to waterlogging stress. Our experimental results showed that waterlogging stress led to leaf chlorosis, 35 days after treatment. A significant decrease in leaf fresh weight, chlorophyll and sugar content supported this phenotypic change. Biochemical analysis showed a significant increase in leaf proline, lipid peroxidase and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical content of waterlogged plants. To elucidate the molecular mechanisms, we conducted RNA-sequencing (RNA-seq) and de novo assembly. Using RNA-seq analysis approach and filtering (P  < 0.05 and false discovery rate <0.001), we obtained 134 unigenes upregulated and 574 unigenes downregulated. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis placed the obtained differentially expressed unigenes in α-linoleic pathway, fatty acid degradation, glycosis, glycolipid metabolism and oligosaccharide biosynthesis process. Mapping of unigenes with Arabidopsis using basic local alignment search tool for nucleotides showed several critical genes in photosynthesis and carbon metabolism downregulated. Following this, we found the repression of multiple nitrogen (N) assimilation and nucleotide biosynthesis genes including purine metabolism. In addition, waterlogging stress reduced the levels of polyunsaturated fatty acids with a concomitant increase only in myristic acid. Together, our results indicate that the prolonged snowmelt may cause inability of A. koreana seedlings to lead the photosynthesis normally due to the lack of root intercellular oxygen and emphasizes a detrimental effect on the N metabolic pathway, compromising this endangered tree's ability to be fully functional under waterlogging stress. [ABSTRACT FROM AUTHOR]