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Spring phenology is a key indicator of temperate and boreal ecosystems' response to climate change. To date, most phenological studies have analyzed the mean date of budburst in tree populations while overlooking the large variability of budburst among individual trees. The consequences of neglecting the within-population variability (WPV) of budburst when projecting the dynamics of tree communities are unknown. Here, we develop the first model designed to simulate the WPV of budburst in tree populations. We calibrated and evaluated the model on 48 442 budburst observations collected between 2000 and 2022 in three major temperate deciduous trees, namely, hornbeam (Carpinus betulus), oak (Quercus petraea) and chestnut (Castanea sativa). The WPV model received support for all three species, with a root mean square error of 5.7 ± 0.5 d for the prediction of unknown data. Retrospective simulations over 1961–2022 indicated earlier budburst as a consequence of ongoing climate warming. However, simulations revealed no significant change for the duration of budburst (DurBB, i.e., the time interval from BP20 to BP80 (with BP representing budburst percent), which respectively represent the date when 20 % and 80 % of trees in a population have reached budburst), due to a lack of significant temperature increase during DurBB in the past. This work can serve as a basis for the development of models targeting intra-population variability of other functional traits, which is of increasing interest in the context of climate change.

In search of the origins of the extraordinary low twinning stress of Ni-Mn-Ga 10M martensite, we studied the temperature induced changes in lattice parameters of Ni50Mn25+xGa25−x (x = 2.7–3.9) single crystal samples and compared them with twinning stress dependences. The alloys exhibited transformation to five-layered (10M) martensite structure (cubic to monoclinic) between 297 to 328 K and exhibited the magnetic shape memory effect in martensite. The structural changes were monitored using x-ray diffraction in the temperature range 200–343 K. The 10M structure was approximated by monoclinic lattice, a = b > c, γ > 90° with the coordinates derived from the cubic unit cell of the parent L21 phase. The lattice parameters γ and c/a correlate well with the universal linear increase of twinning stress of type 1 twins with decreasing temperature. On the contrary, the twinning stress is not affected by differences between a and b and thus a/b twins seem to play no role in a − c twin boundary motion resulting in magnetically induced reorientation. [ABSTRACT FROM AUTHOR]

Lammas growth of trees means the additional growth of the shoot after the growth cessation and bud set in late summer. In temperate tree species, lammas growth occurs irregularly and is often regarded as abnormal, disturbed growth. In subtropical tree species, however, lammas growth is a prevalent phenomenon, possibly due to the prolonged occurrence of high temperatures in the autumn. The occurrence of lammas growth extends the growing season of trees, but its influence on subsequent dormancy phenomena and bud burst phenology remains largely unexplored. By comparing seedlings showing lammas growth with others not showing it, we carried out an experimental study of how lammas growth affects the bud burst phenology and the underlying dormancy phenomena under both ambient and controlled chilling, forcing and warming conditions in four subtropical tree species: Carya illinoinensis, Cinnamomum japonicum, Phoebe chekiangensis and Torreya grandis. With the exception of C. illinoinensis, lammas growth delayed bud burst in all the species under ambient conditions. In the chilling experiment, the delayed bud burst appeared to be due to higher minimum forcing requirement, higher dormancy depth, and in T. grandis, also due to lower chilling sensitivity in the lammas-growth seedlings than in the non-lammas-growth ones. However, a spring warming experiment showed that the sensitivity of bud burst to spring temperatures was higher in the lammas-growth seedlings than in the non-lammas-growth ones. Because of this, the difference between the two phenotypes in the timing of bud burst vanished with increasing warming. Our findings elucidate the significant impact of lammas growth on the dormancy dynamics of subtropical tree species, highlighting the necessity to better understand how the physiological phenomena causing lammas growth change the trees' subsequent environmental responses under changing climatic conditions., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

Forests are increasingly exposed to extreme global warming-induced climatic events. However, the immediate and carry-over effects of extreme events on forests are still poorly understood. Gross primary productivity (GPP) capacity is regarded as a good proxy of the ecosystem's functional stability, reflecting its physiological response to its surroundings. Using eddy covariance data from 34 forest sites in the Northern Hemisphere, we analyzed the immediate and carry-over effects of late-spring frost (LSF) and growing season drought on needle-leaf and broadleaf forests. Path analysis was applied to reveal the plausible reasons behind the varied responses of forests to extreme events. The results show that LSF had clear immediate effects on the GPP capacity of both needle-leaf and broadleaf forests. However, GPP capacity in needle-leaf forests was more sensitive to drought than in broadleaf forests. There was no interaction between LSF and drought in either needle-leaf or broadleaf forests. Drought effects were still visible when LSF and drought coexisted in needle-leaf forests. Path analysis further showed that the response of GPP capacity to drought differed between needle-leaf and broadleaf forests, mainly due to the difference in the sensitivity of canopy conductance. Moreover, LSF had a more severe and long-lasting carry-over effect on forests than drought. These results enrich our understanding of the mechanisms of forest response to extreme events across forest types., (© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

We predict heavy quark production cross sections in deep inelastic scattering at high energy by applying the color glass condensate effective theory. We demonstrate that, when the calculation is performed consistently at next-to-leading order accuracy with massive quarks, it becomes possible, for the first time in the dipole picture with perturbatively calculated center-of-mass energy evolution, to simultaneously describe both the light and heavy quark production data at small x_{Bj}. Furthermore, we show how the heavy quark cross section data provides additional strong constraints on the extracted nonperturbative initial condition for the small-x_{Bj} evolution equations.

Bud dormancy and its release are complex physiological phenomena in plants. The molecular mechanisms of bud dormancy in Liriodendron chinense are mainly unknown. Here, we studied bud dormancy and the related physiological and molecular phenomena in Liriodendron under long-day (LD) and short-day (SD). Bud burst was released faster under LD than under SD. Abscisic acid (ABA), superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR) activities were increased significantly under LD in Liriodendron buds. In contrast, the contents of gibberellic acid (GA3), ascorbic acid (AsA), glutathione (GSH), malondialdehyde (MDA), and ascorbate peroxidase (APX) activity decreased under LD but increased under SD. Differentially expressed genes (DEGs) were up-regulated under LD and down-regulated under SD and these changes correspondingly promoted (LD) or repressed (SD) cell division and the number and/or size of cells in the bud. Transcriptomic analysis of Liriodendron buds under different photoperiods identified 187 DEGs enriched in several pathways such as flavonoid biosynthesis and phenylpropanoid biosynthesis, plant hormone and signal transduction, etc. that are associated with antioxidant enzymes, non-enzymatic antioxidants, and subsequently promote the growth of the buds. Our findings provide novel insights into regulating bud dormancy via flavonoid and phenylpropanoid biosynthesis, plant hormone and signal transduction pathways, and ABA content. These physiological and biochemical traits would help detect bud dormancy in plants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Climate warming has significantly altered the phenology of plants in recent decades. However, in contrast to the widely reported warming-induced extension of vegetative growing season, the response of fruit development period (FDP) from flowering to fruiting remains largely unexplored, particularly for woody plants. Analyzing >560,000 in situ observations of both flowering and fruiting dates for six temperate woody species across 2958 European phenological observations sites during 1980-2013, we found that in all species both flowering and fruiting phenology, that is, the FDP, advanced with climate warming. However, the advancing rates of the two events were not necessarily equal for any given species, resulting in divergent changes in the length of FDP among species with climate warming. During 1980-2013, not only the temperature during FDP but also the forcing requirement for fruit development increased, both affecting the length of FDP. The shortened FDP was mainly due to elevated temperature, thus accelerating the accumulation of forcing, whereas the prolonged FDP was primarily caused by the substantial increase of the forcing requirement of fruiting, which could be fulfilled only in a longer time and thus slowed down the advance of fruiting. This study provides large-scale empirical evidence of warming-induced advances of FDP but divergent changes in its length in temperate woody species. Our findings demonstrate the contrasting reproductive phenological strategies among temperate woody species under the pressure of warming climate, contrary to the lengthening of vegetative growing season, which is by and largely similar with different woody species., (© 2022 John Wiley & Sons Ltd.)

Pecan ( Carya illinoinensis ) is an important nut tree species in its native areas in temperate and subtropical North America, and as an introduced crop in subtropical southeastern China as well. We used process-based modeling to assess the effects of climatic warming in southeastern China on the leaf-out phenology of pecan seedlings and the subsequent risk of "false springs," i.e., damage caused by low temperatures occurring as a result of prematurely leafing out. In order to maximize the biological realism of the model used in scenario simulations, we developed the model on the basis of experiments explicitly designed for determining the responses modeled. The model showed reasonable internal accuracy when calibrated against leaf-out observations in a whole-tree chamber (WTC) experiment with nine different natural-like fluctuating temperature treatments. The model was used to project the timing of leaf-out in the period 2022-2099 under the warming scenarios RCP4.5 and RCP8.5 in southeastern China. Two locations in the main pecan cultivation area in the northern subtropical zone and one location south of the main cultivation area were addressed. Generally, an advancing trend of leaf-out was projected for all the three locations under both warming scenarios, but in the southern location, a delay was projected under RCP8.5 in many years during the first decades of the 21st century. In the two northern locations, cold damage caused by false springs was projected to occur once in 15-26 years at most, suggesting that pecan cultivation can be continued relatively safely in these two locations. Paradoxically, more frequent cold damage was projected for the southern location than for the two northern locations. The results for the southern location also differed from those for the northern locations in that more frequent cold damage was projected under the RCP4.5 warming scenario (once in 6 years) than under the RCP8.5 scenario (once in 11 years) in the southern location. Due to the uncertainties of the model applied, our conclusions need to be re-examined in an additional experimental study and further model development based on it; but on the basis of our present results, we do not recommend starting large-scale pecan cultivation in locations south of the present main pecan cultivation area in southeastern subtropical China., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zheng, Hänninen, Lin, Shen and Zhang.)

Endodormancy and the related chilling requirement synchronize the seasonal development of trees from the boreal and temperate regions under the climatic conditions prevailing at their native growing sites. The phenomenon of endodormancy has been known at the whole-plant level for 100 years, and in the last couple of decades, insights into the physiological and molecular basis of endodormancy and its release have also been obtained. Intriguingly, recent studies have shown experimentally that subtropical trees also show endodormancy and a chilling requirement. Motivated by the climatic differences between the subtropical and more northern zones, here we address the similarities and differences in endodormancy between trees growing in the subtropical zone and those growing in more northern zones., (© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.)

Studies addressing endodormancy release in adult trees are usually carried out using twigs detached from the trees in the experiments. Potential problems caused by cutting the root-shoot connection when detaching the twigs can be avoided by using grafts as the experimental material. We studied the effects of chilling on the endodormancy release in Norway spruce (Picea abies (L.) Karst.) grafts where twigs of 16-, 32- and 80-year-old trees were used as the scions. The grafts were first exposed to chilling in natural conditions and then samples of them were transferred at intervals to a regrowth test in forcing conditions in a greenhouse. The bud burst percentage, BB%, in the forcing conditions generally increased from zero to near 100% with increasing previous chilling accumulation from mid-October until mid-November, indicating that endodormancy was released in almost all of the grafts by mid-November. The days to bud burst, DBB, decreased in the forcing conditions with successively later transfers until the next spring. Neither BB% nor DBB was dependent on the age of the scion. However, in the early phase of ecodormancy release, the microscopic internal development of the buds was more advanced in the grafts representing the 16-year-old than in those representing the 32- or 80-year-old trees. In conclusion, our findings suggest that no major change in the environmental regulation of endodormancy release in Norway spruce takes place when the trees get older. Taken together with earlier findings with Norway spruce seedlings, our results suggest that regardless of the seedling or tree age, the chilling requirement of endodormancy release is met in late autumn. The implications of our findings for Norway spruce phenology under climatic warming and the limitations of our novel method of using grafts as a proxy of trees of different ages are discussed., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

Hydrocarbons fuel our economy. Furthermore, intermediate goods and consumer products are often hydrocarbon-based. Beside all the progress they made possible, hydrogen-containing substances can have severe detrimental effects on materials exposed to them. Hydrogen-assisted failure of iron alloys has been recognised more than a century ago. The present study aims to providing further insight into the degradation of the austenitic stainless steel AISI 304L (EN 1.4307) exposed to hydrogen. To this end, samples were electrochemically charged with the hydrogen isotope deuterium ( 2 H, D) and analysed by scanning electron microscopy (SEM), electron back-scatter diffraction (EBSD) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). It was found that deuterium caused a phase transformation from the original γ austenite into ε- and α'-martensite. Despite their low solubility for hydrogen, viz. deuterium, the newly formed phases showed high deuterium concentration which was attributed to the increased density of traps. Information about the behaviour of deuterium in the material subjected to external mechanical load was gathered. A four-point-bending device was developed for this purpose. This allowed to analyse in-situ pre-charged samples in the ToF-SIMS during the application of external mechanical load. The results indicate a movement of deuterium towards the regions of highest stress.

Fruits of hickory ( Carya cathayensis ) are larger and their peel is greener after interspecific pollination by pecan ( Carya illinoinensis ; later pp fruits) than after intraspecific pollination by hickory (later ph fruits). Previous studies have found little genetic differences between offspring and their maternal parent, indicating that the observed trait differences between pp and ph fruits are due to metaxenia. Fruit development depends on the amount of photosynthetic assimilate available. Since there is no difference in photosynthesis of the associated leaves between pp and ph fruits, the larger size of the pp fruits might be attributed to changes in fruit photosynthesis caused by the different pollen sources. To elucidate to the photosynthetic mechanisms behind the metaxenia effect on fruit development in hickory, the effects of intraspecific and interspecific pollination regimes were examined in the present study. We observed the photosynthetic capacity in the peel of fruits and the related ecophysiological and morphological traits of both ph and pp fruits over a period of 120 days after pollination. Significant differences in the appearance and dry weight between ph and pp fruits were observed at 50 days after pollination (DAP). More than 70% of dry matter accumulation of the fruits was completed during 60-120 DAP, while the true photosynthetic rate of the associated leaves significantly decreased by about 50% during the same period. In several cell layers of the peel, the number of chloroplasts per cell was significantly higher in pp than in ph fruits. Similarly, the ribulose 1, 5-bisphosphate carboxylase (Rubisco) activity, the total chlorophyll content, and the nitrogen content were all significantly higher in pp than in ph fruits during all growth stages; and all of these physiological quantities were positively correlated with the gross photosynthetic rate of the fruits. We conclude that the enhanced photosynthetic capacity of pp fruits contributes to their fast dry matter accumulation and oil formation. This result will provide a theoretical basis for improving hickory fruit yields in practical cultivation., (Copyright © 2020 Huang, Zhang, Zhang, Huang, Hänninen, Huang and Hu.)

Bud dormancy of plants has traditionally been explained either by physiological growth arresting conditions in the bud or by unfavourable environmental conditions, such as non-growth-promoting low air temperatures. This conceptual dichotomy has provided the framework also for developing process-based plant phenology models. Here, we propose a novel model that in addition to covering the classical dichotomy as a special case also allows the quantification of an interaction of physiological and environmental factors. According to this plant-environment interaction suggested conceptually decades ago, rather than being unambiguous, the concept of "non-growth-promoting low air temperature" depends on the dormancy status of the plant. We parameterized the model with experimental results of growth onset for seven boreal plant species and found that based on the strength of the interaction, the species can be classified into three dormancy types, only one of which represents the traditional dichotomy. We also tested the model with four species in an independent experiment. Our study suggests that interaction of environmental and physiological factors may be involved in many such phenomena that have until now been considered simply as plant traits without any considerations of effects of the environmental factors., (© 2019 John Wiley & Sons Ltd.)

Ppmar1 and Ppmar2 are two active mariner -like elements (MLEs) cloned from moso bamboo ( Phyllostachys edulis (Carrière) J. Houz) genome possessing transposases that harbour nuclear export signal (NES) domain, but not any nuclear localization signal (NLS) domain. To understand the functions of NES in transposon activity, we have conducted two experiments, fluorescence and excision frequency assays in the yeast system. For this, by site-directed mutagenesis, three NES mutants were developed from each of the MLE. In the fluorescence assay, the mutants, NES-1 , 2 and 3 along with the wild types ( NES-0 ) were fused with fluorescent proteins, enhanced yellow fluorescent protein (EYFP) and enhanced cyan fluorescent protein (ECFP) were co-transformed into yeast system. To differentiate protein localisation under the NES influence, ECFP alone was fused to wild and mutant NES domains either on N- or C-terminal and not to EYFP. Fluorescence assay revealed that blue fluorescence of ECFP was more intense than the red fluorescence of the EYFP in the yeast cell matrix. Further, ECFP had a wider localisation in the cellular matrix, but EYFP was largely located in the nucleus. The NES-1 domain was related to the comparatively high spread of ECFP, while NES-2 and NES-3 indicated a low spread, implying that NES activity on nuclear export increased when the NES is made leucine-rich, while the signalling activity was reduced when the leucine content was lowered in the NES domain. In the transposon excision assay, the mutant and wild type NES of both the Ppmar elements were integrated into an Ade2 vector, and within the Ade2 gene. Co-transformation of the vector together with non-autonomous Ppmar transposons and NES-lacking transposases was used to assess the differential excision frequencies of the mutants NES domains. In both the MLEs, NES-1 had the highest excision suppression, which was less than half of the excision frequency of the wild type. NES-2 and NES-3 elements showed, up to three times increase in transposon excision than the wild types. The results suggested that NES is an important regulator of nuclear export of transposase in Ppmar elements and the mutation of the NES domains can either increase or decrease the export signalling. We speculate that in moso bamboo, NESs regulates the transposition activity of MLEs to maintain the genome integrity., Competing Interests: Competing interestsThe authors declare that they have no competing interests.

Additive manufacturing (AM) is a rapidly growing field of technology. In order to increase the variety of metal alloys applicable for AM, selective laser melting (SLM) of duplex stainless steel 2205 powder and the resulting microstructure, density, mechanical properties, and corrosion resistance were investigated. An optimal set of processing parameters for producing high density (>99.9%) material was established. Various post-processing heat treatments were applied on the as-built predominantly ferritic material to achieve the desired dual-phase microstructure. Effects of annealing at temperatures of 950 °C, 1000 °C, 1050 °C, and 1100 °C on microstructure, crystallographic texture, and phase balance were examined. As a result of annealing, 40-46 vol.% of austenite phase was formed. Annealing decreased the high yield and tensile strength values of the as-built material, but significantly increased the ductility. Annealing also decreased the residual stresses in the material. Mechanical properties of the SLM-processed and heat-treated materials outperformed those of conventionally produced alloy counterparts. Using a scanning strategy with 66° rotation between layers decreased the strength of the crystallographic texture. Electrochemical cyclic potentiodynamic polarization testing in 0.6 M NaCl solution at room temperature showed that the heat treatment improved the pitting corrosion resistance of the as-built SLM-processed material., Competing Interests: The authors declare no conflict of interest.

Leaf senescence (LS) affects tree fitness, species distribution and ecosystem structure and functioning. The drivers of LS and the processes underlying it have been studied, but the studies have mainly focused on environmental cues and have mainly been based on statistical analyses using in situ data sets. Experimental investigation and field verification of the processes and drivers are thus urgently needed. We conducted a nutrient-addition experiment after a spring-warming experiment in which an ~40-day range of leaf-out (LO) dates was induced in horse chestnut (Aesculus hippocastanum) and beech (Fagus sylvatica) saplings. We found that both increased nutrient supply and advanced LO date significantly affected the timing of LS, but their effects were opposite, as the former delayed and the latter advanced the senescence. The effects of nutrient supply and LO interacted species specifically. In chestnut, the delay of senescence caused by fertilization increased with the delay of LO and was thus stronger for individuals that flushed late in the spring. On the contrary, in beech the delay of senescence caused by fertilization decreased with the delay of LO and was insignificant for individuals with the latest LO. The experimental findings for beech were confirmed with mature trees at a regional scale. The interactive effect between nutrients and LO on senescence may be associated with variable sensitivity to photoperiod, growth sink limitation and/or direct effect of foliar nutrition on the timing of senescence. Our novel results show that the interactive effects of LO and nutrient supply on the timing of LS should be further addressed experimentally in forthcoming studies. It would also be interesting to consider our results in the further development of phenological models used in assessing the effects of climatic change. The differences found in the present study between horse chestnut and beech suggest that the results found for one species cannot necessarily be generalized to other species, so studies with different temperate tree species are called for., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Mariner-like elements (MLE) are a super-family of DNA transposons widespread in animal and plant genomes. Based on their transposition characteristics, such as random insertions and high-frequency heterogeneous transpositions, several MLEs have been developed to be used as tools in gene tagging and gene therapy. Two active MLEs, Ppmar1 and Ppmar2 , have previously been identified in moso bamboo ( Phyllostachys edulis ). Both of these have a preferential insertion affinity to AT-rich region and their insertion sites are close to random in the host genome. In Ppmar2 element, we studied the affinities of terminal inverted repeats (TIRs) to DNA binding domain (DBD) and their influence on the transposition activity. We could identify two putative boxes in the TIRs which play a significant role in defining the TIR's affinities to the DBD. Seven mutated TIRs were constructed, differing in affinities based on similarities with those of other plant MLEs. Gel mobility shift assays showed that the TIR mutants with mutation sites G669A-C671A had significantly higher affinities than the mutants with mutation sites C657T-A660T. The high-affinity TIRs indicated that their transposition frequency was 1.5-2.0 times higher than that of the wild type TIRs in yeast transposition assays. The MLE mutants with low-affinity TIRs had relatively lower transposition frequency from that of wild types. We conclude that TIR affinity to DBD significantly affects the transposition activity of Ppmar2 . The mutant MLEs highly active TIRs constructed in this study can be used as a tool for bamboo genetic studies.

Contrary to the generally advanced spring leaf unfolding under global warming, the effects of the climate warming on autumn leaf senescence are highly variable with advanced, delayed, and unchanged patterns being all reported. Using one million records of leaf phenology from four dominant temperate species in Europe, we investigated the temperature sensitivities of spring leaf unfolding and autumn leaf senescence (S T , advanced or delayed days per degree Celsius). The S T of spring phenology in all of the four examined species showed an increase and decrease during 1951-1980 and 1981-2013, respectively. The decrease in the S T during 1981-2013 appears to be caused by reduced accumulation of chilling units. As with spring phenology, the S T of leaf senescence of early successional and exotic species started to decline since 1980. In contrast, for late successional species, the S T of autumn senescence showed an increase for the entire study period from 1951 to 2013. Moreover, the impacts of rising temperature associated with global warming on spring leaf unfolding were stronger than those on autumn leaf senescence. The timing of leaf senescence was positively correlated with the timing of leaf unfolding during 1951-1980. However, as climate warming continued, the differences in the responses between spring and autumn phenology gradually increased, so that the correlation was no more significant during 1981-2013. Our results further suggest that since 2000, due to the decreased temperature sensitivity of leaf unfolding the length of the growing season has not increased any more. These finding needs to be addressed in vegetation models used for assessing the effects of climate change., (© 2018 John Wiley & Sons Ltd.)

In boreal and temperate trees, air temperature is a major environmental factor regulating the timing of spring phenological events, such as vegetative bud burst, through underlying physiological processes. This has been established by experimental research, and mathematical process-based tree phenology models have been developed based on the results. The models have often been applied when assessing the effects of climate change. Currently, there is an increasing trend to develop process-based tree phenology models using only observational phenological records from natural conditions. We point out that this method runs a high risk of producing models that do not simulate the real physiological processes in the trees and discuss experimental designs facilitating the development of biologically realistic process-based models for tree spring phenology., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Frost events during the active growth period of plants can cause extensive frost damage with tremendous economic losses and dramatic ecological consequences. A common assumption is that climate warming may bring along a reduction in the frequency and severity of frost damage to vegetation. On the other hand, it has been argued that rising temperature in late winter and early spring might trigger the so called "false spring", that is, early onset of growth that is followed by cold spells, resulting in increased frost damage. By combining daily gridded climate data and 1,489 k in situ phenological observations of 27 tree species from 5,565 phenological observation sites in Europe, we show here that temporal changes in the risk of spring frost damage with recent warming vary largely depending on the species and geographical locations. Species whose phenology was especially sensitive to climate warming tended to have increased risk of frost damage. Geographically, compared with continental areas, maritime and coastal areas in Europe were more exposed to increasing occurrence of frost and these late spring frosts were getting more severe in the maritime and coastal areas. Our results suggest that even though temperatures will be elevated in the future, some phenologically responsive species and many populations of a given species will paradoxically experience more frost damage in the future warming climate. More attention should be paid to the increased frost damage in responsive species and populations in maritime areas when developing strategies to mitigate the potential negative impacts of climate change on ecosystems in the near future., (© 2018 John Wiley & Sons Ltd.)

Aims: The value of single-photon emission tomography (SPECT) in patients with severe chronic kidney disease is controversial, and the implications of SPECT finding with lower level of ischaemia are unknown. We assessed the prognostic value of SPECT in patients evaluated for kidney transplantation., Methods and Results: Five hundred and forty-eight patients underwent SPECT as a part of routine evaluation for kidney transplantation. During the median follow-up of 43.7 months (IQR 22.4-68.4 months), 112 patients (20.4%) died, 49 of cardiovascular (CV) causes (8.9%). In comparison to those with no perfusion defects, mild perfusion abnormalities (1%-9.9%) had an adjusted Cox hazard ratio (HR) of 1.80 [95% confidence interval (95% CI) 1.02-3.17, P = 0.041] for all-cause mortality, while large perfusion defects (≥10%) demonstrated an HR of 2.20 (95% CI 1.38-3.50, P = 0.001). A competing risk analysis produced a similar prognostic capacity for CV mortality. SPECT also offered incremental prognostic impact with two reclassification methods. Revascularization was performed clearly more often on patients with severely than mildly abnormal or normal SPECT (28.0%, 4.3%, and 1.3%, respectively, P < 0.001). However, revascularization was not linked with better survival. Patients with a normal SPECT received a kidney transplant more often than patients with a mildly or severely abnormal SPECT (50.5%, 36.2%, and 36.6%, respectively, P = 0.010)., Conclusion: Myocardial ischaemia in SPECT is clearly linked with mortality in patients screened for kidney transplantation. Contrary to populations with coronary artery disease, even a mild perfusion defect in SPECT predicts poor prognosis in this patient population. The finding deserves further attention in forthcoming trials.

Under current global warming, high-elevation regions are expected to experience faster warming than low-elevation regions. However, due to the lack of studies based on long-term large-scale data, the relationship between tree spring phenology and the elevation-dependent warming is unclear. Using 652k records of leaf unfolding of five temperate tree species monitored during 1951-2013 in situ in Europe, we discovered a nonlinear trend in the altitudinal sensitivity (S A , shifted days per 100 m in altitude) in spring phenology. A delayed leaf unfolding (2.7 ± 0.6 days per decade) was observed at high elevations possibly due to decreased spring forcing between 1951 and 1980. The delayed leaf unfolding at high-elevation regions was companied by a simultaneous advancing of leaf unfolding at low elevations. These divergent trends contributed to a significant increase in the S A (0.36 ± 0.07 days 100/m per decade) during 1951-1980. Since 1980, the S A started to decline with a rate of -0.32 ± 0.07 days 100/m per decade, possibly due to reduced chilling at low elevations and improved efficiency of spring forcing in advancing the leaf unfolding at high elevations, the latter being caused by increased chilling. Our results suggest that due to both different temperature changes at the different altitudes, and the different tree responses to these changes, the tree phenology has shifted at different rates leading to a more uniform phenology at different altitudes during recent decades., (© 2018 John Wiley & Sons Ltd.)

Climate warming is substantially shifting the leaf phenological events of plants, and thereby impacting on their individual fitness and also on the structure and functioning of ecosystems. Previous studies have largely focused on the climate impact on spring phenology, and to date the processes underlying leaf senescence and their associated environmental drivers remain poorly understood. In this study, experiments with temperature gradients imposed during the summer and autumn were conducted on saplings of European beech to explore the temperature responses of leaf senescence. An additional warming experiment during winter enabled us to assess the differences in temperature responses of spring leaf-out and autumn leaf senescence. We found that warming significantly delayed the dates of leaf senescence both during summer and autumn warming, with similar temperature sensitivities (6-8 days delay per °C warming), suggesting that, in the absence of water and nutrient limitation, temperature may be a dominant factor controlling the leaf senescence in European beech. Interestingly, we found a significantly larger temperature response of autumn leaf senescence than of spring leaf-out. This suggests a possible larger contribution of delays in autumn senescence, than of the advancement in spring leaf-out, to extending the growing season under future warmer conditions., (© 2017 John Wiley & Sons Ltd.)

Due to infrequent sexual reproduction, moso bamboo breeding by hybridization is extremely technically difficult. Insertional mutagenesis based on endogenous active transposons may thus serve as an alternative method to create new germplasm of moso bamboo. In the present study, using LTR-STRUC, a full-length intact long terminal repeat (LTR) retrotransposon was identified in the moso bamboo genome and was named PHRE2 (Phyllostachys edulis retrotransposon 2). The 5' and 3' LTR sequences of PHRE2 were highly (98.39%) similar. PHRE2 contains all domains necessary for transposition such as gag, pr, rt, rh, and int. The coding frames of these essential domains were complete and had no apparent mutations. In addition, PHRE2 possessed a prime binding site (PBS), a polypurine tract (PPT), and two typical sequences of LTR retrotransposons. A genome-wide scan showed that the moso bamboo genome has only one full-length sequence of PHYRE2. After its transfer to Arabidopsis thaliana, an increase in PHRE2 copy number occurred in the T 3 plants compared to in the T 2 plants. After moso bamboo seedlings were grown in tissue culture or treated by irradiation or plant hormones, the copy number of PHRE2 significantly increased. These findings indicate that PHRE2 has the capacity for transposition, which can be induced by environmental conditions.

Background: Large myocardial infarction (MI) is associated with adverse left ventricular (LV) remodeling (LVR). We studied the nature of LVR, with specific attention to non-transmural MIs, and the association of peak CK-MB with recovery and chronic phase scar size and LVR., Methods: Altogether 41 patients underwent prospectively repeated cardiovascular magnetic resonance at a median of 22 (interquartile range 9-29) days and 10 (8-16) months after the first revascularized MI. Transmural MI was defined as ≥75% enhancement in at least one myocardial segment., Results: Peak CK-MB was 86 (40-216) μg/L in median, while recovery and chronic phase scar size were 13 (3-23) % and 8 (2-19) %. Altogether 33 patients (81%) had a non-transmural MI. Peak CK-MB had a strong correlation with recovery and chronic scar size (r ≥ 0.80 for all, r ≥ 0.74 for non-transmural MIs; p < 0.001). Peak CK-MB, recovery scar size, and chronic scar size, were all strongly correlated with chronic wall motion abnormality index (WMAi) (r ≥ 0.75 for all, r ≥ 0.73 for non-transmural MIs; p < 0.001). There was proportional scar size and LV mass resorption of 26% (0-50%) and 6% (- 2-14%) in median. Young age (< 60 years, median) was associated with greater LV mass resorption (median 9%vs.1%, p = 0.007)., Conclusions: Peak CK-MB has a strong association with chronic scar size and wall motion abnormalities after revascularized non-transmural MI. Considerable infarct resorption happens after the first-month recovery phase. LV mass resorption is related to age, being more common in younger patients.

Seed oil content is an important trait of nut seeds, and it is affected by the import of carbon from photosynthetic sources. Although green leaves are the main photosynthetic organs, seed sarcotesta photosynthesis also supplies assimilates to seed development. Understanding the relationship between seed photosynthesis and seed development has theoretical and practical significance in the cultivation of Torreya grandis cv. "Merrillii." To assess the role of seed sarcotesta photosynthesis on the seed development, anatomical and physiological traits of sarcotesta were measured during two growing seasons in the field. Compared with the attached current-year leaves, the sarcotesta had higher gross photosynthetic rate at the first stage of seed development. At the late second stage of seed development, sarcotesta showed down-regulation of PSII activity, as indicated by significant decrease in the following chlorophyll fluorescence parameters: the maximum PSII efficiency ( F v /F m ), the PSII quantum yield (Φ PSII ), and the photosynthetic quenching coefficient ( qP ). The ribulose 1, 5-bisphosphate carboxylase (Rubisco) activity, the total chlorophyll content (Chl (a+b) ) and nitrogen content in the sarcotesta were also significantly decreased during that period. Treatment with DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea] preventing seed photosynthesis decreased the seed dry weight and the oil content by 25.4 and 25.5%, respectively. We conclude that seed photosynthesis plays an important role in the dry matter accumulation at the first growth stage. Our results also suggest that down-regulation of seed photosynthesis is a plant response to re-balance the source-sink ratio at the second growth stage. These results suggest that seed photosynthesis is important for biomass accumulation and oil synthesis of the Torreya seeds. The results will facilitate achieving higher yields and oil contents in nut trees by selection for higher seed photosynthesis cultivars.

Background/objectives: Orthognathic treatment is routine practice to rehabilitate severe malocclusions and dentofacial deformities. Because orthognathic treatment is elective, patient's involvement in deciding whether to proceed with treatment is vital. Interaction and communication between patient and treating team plays a key role in achieving post-treatment satisfaction. To achieve satisfaction, an orthognathic 'information clinic' for prospective orthognathic patients was established at Oral and Maxillofacial Unit, Tampere University Hospital, Finland. 'Information clinic' includes short talks with power-point presentation given by orthodontist, oral hygienist, oral and maxillofacial surgeon, psychologist, and previous patient. Aim of the study was to set up an 'information clinic' and, more specifically, 1. to assess patients' opinions on the 'clinic' during pilot phase (2013-14) and 2. to analyse general statistics during the first 3 years (2013-16)., Methods: During the pilot phase, patient opinions, based on voluntary questionnaire, were obtained from 85 people. General data were collected for the clinics run in 2013-16., Results: Seventy-two per cent of respondents reported the information provided to help in their decision-making to proceed/not proceed with treatment. Majority considered the information about the surgical aspects and meeting patient who had undergone orthognathic treatment to be the most important part of the clinic. Between March 2013 and 2016, 290 prospective orthognathic patients were invited to 29 'information clinics'. One hundred and ninety-four patients attended, of whom 137 were female and 57 male (age range 15-67 years)., Conclusions: The questionnaire and verbal feedback from the patients was positive; hence, the 'information clinic' is now offered as a routine process to all prospective orthognathic patients in our clinic., (© The Author 2017. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com)

Atmospheric nitrogen (N) deposition can increase the susceptibility of vascular plants to other stresses, but the physiological basis of such a response remains poorly understood. This study was designed to clarify the physiological mechanisms and to evaluate bioindicators of N deposition impact on vascular plants. We evaluate multiple physiological responses to ~4 years of simulated additional N deposition (30-90 kg N ha -1 year -1 ) on three age-classes (1a, 3a, and 5a) of Moso bamboo. A saturating response to the additional N deposition was found both in foliar N concentration and in P n . However, 3- and 5-year-old bamboo seemed to be less tolerant to extremely high N deposition than 1-year-old bamboo since they were saturated at a lower N addition. Furthermore, C/N/P stoichiometric ratios were very sensitive to N deposition in all three-age classes of bamboo, but the responses to N deposition in the various age-classes were diverse. We also found that the highest additional N deposition suppressed stomatal conductance and transpiration rate, suggesting an induced water stress. The stress induced by the high N load was also seen in photochemistry, where it reduced potential and actual photosynthetic use of light energy, diminished photo-protection capacity, and increased risk of the photo-damage. High additional N deposition contributed to a decrease in the foliar soluble protein contents and to an increase in the peroxidase activity (POD). Our study suggested, for the first time, that although the photosynthetic rate was enhanced by the increased N deposition in Moso bamboo, long-term high N load causes negative effects, such as damage to photosystem II. In Moso bamboo photochemical parameters are more sensitive to N deposition than photosynthetic rate or foliar N concentration. Furthermore, plant age should be taken into account when assessing plants' susceptibility to changes in global change drivers, such as N deposition. These findings facilitate the revealing of the risks potentially caused to vascular plants by increased N deposition before any visible symptoms of injury are seen.

Susceptibility of three lean-alloyed ferritic-austenitic stainless steels to hydrogen-induced delayed cracking was examined, concentrating on internal hydrogen contained in the materials after production operations. The aim was to study the role of strain-induced austenite to martensite transformation in the delayed cracking susceptibility. According to the conducted deep drawing tests and constant load tensile testing, the studied materials seem not to be particularly susceptible to delayed cracking. Delayed cracks were only occasionally initiated in two of the materials at high local stress levels. However, if a delayed crack initiated in a highly stressed location, strain-induced martensite transformation decreased the crack arrest tendency of the austenite phase in a duplex microstructure. According to electron microscopy examination and electron backscattering diffraction analysis, the fracture mode was predominantly cleavage, and cracks propagated along the body-centered cubic (BCC) phases ferrite and α'-martensite. The BCC crystal structure enables fast diffusion of hydrogen to the crack tip area. No delayed cracking was observed in the stainless steel that had high austenite stability. Thus, it can be concluded that the presence of α'-martensite increases the hydrogen-induced cracking susceptibility., Competing Interests: The authors declare no conflict of interest.

Background: Cardiac magnetic resonance imaging has a key role in today's diagnosis of cardiac sarcoidosis. We set out to investigate whether cardiac magnetic resonance imaging also helps predict outcome in cardiac sarcoidosis., Methods and Results: Our work involved 59 patients with cardiac sarcoidosis (38 female, mean age 46±10 years) seen at our hospital since February 2004 and followed up after contrast-enhanced cardiac magnetic resonance imaging. The extent of myocardial late gadolinium enhancement (measured as percentage of left ventricular mass), the volumes and ejection fractions of the left and right ventricles, and the thickness of the basal interventricular septum were determined and analyzed for prognostic significance. By April 2015, 23 patients had reached the study's end point, consisting of a composite of cardiac death (n=3), cardiac transplantation (n=1), and occurrence of life-threatening ventricular tachyarrhythmias (n=19; ventricular fibrillation in 5 and sustained ventricular tachycardia in 14 patients). In univariate analysis, myocardial extent of late gadolinium enhancement predicted event-free survival, as did scar-like thinning (<4 mm) of the basal interventricular septum and the ejection fraction of the right ventricle (P<0.05 for all). In multivariate Cox regression analysis, extent of late gadolinium enhancement was the only independent predictor of outcome events on cardiac magnetic resonance imaging, with a hazard ratio of 2.22 per tertile (95% CI 1.07-4.59). An extent of late gadolinium enhancement >22% (third tertile) had positive and negative predictive values for serious cardiac events of 75% and 76%, respectively., Conclusions: Findings on cardiac magnetic resonance imaging and the extent of myocardial late gadolinium enhancement in particular help predict serious cardiac events in cardiac sarcoidosis., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

Background: Magnetic resonance imaging (MRI) of pacemaker patients has become available despite of previous contraindications. However, pacing systems containing ferromagnetic material may hamper the diagnostic quality of cardiac MR (CMR) images., Purpose: To study methods for reducing susceptibility-based artifacts in CMR examinations of pacemaker patients., Material and Methods: Altogether 16 patients were scanned with 1.5T MRI scanner using cine balanced steady-state free-precession (bSSFP) and spoiled gradient echo (SPGR) sequences. The use of frequency-scout was also evaluated. For myocardial late gadolinium-enhanced (LGE) imaging, SPGR or bSSFP readout inversion-recovery prepared gradient echo sequences were used with and without phase-sensitive inversion-recovery (PSIR). Two radiologists subjectively compared the image quality (IQ) and the ranges of susceptibility artifacts were evaluated objectively., Results: The IQ proved adequate for diagnosing each patient, although in a few patients with a left-side implanted generator, artifacts hampered IQ in the anterior and anteroseptal segments of the myocardium in bSSFP cine and LGE sequences. In bSSFP cine, the use of frequency-scout could often transfer the banding artifacts away from the left ventricular myocardium. In LGE imaging, the artifacts were more pronounced in IR-bSSFP and PSIR than in IR-SPGR sequences. The ranges of generator-based artifacts were greater in bSSFP (10-12 cm) than in SPGR (6 cm) sequences due to banding artifacts., Conclusion: The artifacts caused by pacemakers typically did not compromise the diagnostic IQ. The use of frequency-scout prior to bSSFP cine or the use of SPGR-based sequences could also improve IQ., (© The Foundation Acta Radiologica 2015.)