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Climate change has resulted in major changes in plant phenology across the globe that includes leaf‐out date and flowering time. The ability of species to respond to climate change, in part, depends on their response to climate as a phenological cue in general. Species that are not phenologically responsive may suffer in the face of continued climate change. Comparative studies of phenology have found phylogeny to be a reliable predictor of mean leaf‐out date and flowering time at both the local and global scales. This is less true for flowering time response (i.e., the correlation between phenological timing and climate factors), while no study to date has explored whether the response of leaf‐out date to climate factors exhibits phylogenetic signal. We used a 52‐year observational phenological dataset for 52 woody species from the Forest Botanical Garden of Heilongjiang Province, China, to test phylogenetic signal in leaf‐out date and flowering time, as well as, the response of these two phenological traits to both temperature and winter precipitation. Leaf‐out date and flowering time were significantly responsive to temperature for most species, advancing, on average, 3.11 and 2.87 day/°C, respectively. Both leaf‐out and flowering, and their responses to temperature exhibited significant phylogenetic signals. The response of leaf‐out date to precipitation exhibited no phylogenetic signal, while flowering time response to precipitation did. Native species tended to have a weaker flowering response to temperature than non‐native species. Earlier leaf‐out species tended to have a greater response to winter precipitation. This study is the first to assess phylogenetic signal of leaf‐out response to climate change, which suggests, that climate change has the potential to shape the plant communities, not only through flowering sensitivity, but also through leaf‐out sensitivity.

The diagnostic of absolute densities of reactive species and gas temperature is of growing interest for many applications. In this paper, we proposed a simple method to determine OH densities and rotational temperatures based on the molecular self-absorption. A 10 cm diffuse atmospheric pressure RF glow discharge is used to verify the proposed method. Good agreements with broadband absorption are achieved with a two-temperature Boltzmann distribution description of the excited state.

A method is proposed that employs the ratios of the 2nd and 4th harmonics at the line center to measure line width under high absorption. The measured line width is then applied in the “calibration-free 2f/1f” formula to detect gas pressure and concentration. To verify this method, the transitions of CO2 at 6,982.0678 cm−1 and H2O at 6,979.2995 cm−1 are selected to measure the line width, gas pressure, and concentration in laboratory and field environments, respectively. Experimental results are very consistent with the expectations.

Summary � Leaf out phenology affects a wide variety of ecosystem processes and ecological interactions and will take on added significance as leaf out times increasingly shift in response to warming temperatures associated with climate change. There is, however, relatively little information available on the factors affecting species differences in leaf out phenology. � An international team of researchers from eight Northern Hemisphere temperate botanical gardens recorded leaf out dates of c. 1600 woody species in 2011 and 2012. � Leaf out dates in woody species differed by as much as 3 months at a single site and exhibited strong phylogenetic and anatomical relationships. On average, angiosperms leafed out earlier than gymnosperms, deciduous species earlier than evergreen species, shrubs earlier than trees, diffuse and semi-ring porous species earlier than ring porous species, and species with smaller diameter xylem vessels earlier than species with larger diameter vessels. The order of species leaf out was generally consistent between years and among sites. � As species distribution and abundance shift due to climate change, interspecific differences in leaf out phenology may affect ecosystem processes such as carbon, water, and nutrient cycling. Our open access leaf out data provide a critical framework for monitoring and modelling such changes going forward.

We propose a method that employs the ratios of the 2nd and 4th harmonics at the line center to measure line shape under low absorption conditions. To verify this method, the transition of CO2 at 6,982.0678 cm−1 is selected to measure line shape by using the proposed method and direct absorption spectroscopy in laboratory conditions. The results from both methods have a high degree of consistency. This satisfactory agreement indicates the validity of the proposed method.

It is well known that spring phenology has advanced in temperate regions over the last few decades in response to climate change. However, we understand much less about climate-driven changes in phenology within subtropical and tropical regions, where the timing of events is less predictable and has not been well-studied. It is not known whether subtropical plants have a similar winter chilling requirement to what has been well-documented in temperate species. To explore this possibility, we established a climate chamber experiment to test the effects of photoperiod and chilling on the timing of budburst within 37 subtropical woody species. We found that both moderate and strong chilling treatments advanced budburst and reduced forcing requirements, relative to plants subjected to a low chilling treatment. Longer photoperiod enhanced budburst rate for only two species, suggesting that chilling is more important for regulating budburst for most species. With respect to future climate change, the spring phenology of subtropical species is expected to be delayed further because species could lack the ability to meet their fundamental chilling requirement. These results have important implications for the conservation and management of tropical and subtropical plant populations under future climate change scenarios.

The measurement of absolute densities of reactive species and radicals such as OH is of growing interest for many plasma applications. In this paper, we extend the use of a self-absorption model for atomic emission spectroscopy to molecular emission spectroscopy. The proposed analysis of self-absorbed molecular emission spectra is a simple and inexpensive method to determine OH(X) densities and rotational temperatures compared to laser induced fluorescence. We compare the recorded absolute OH density in a non-equilibrium diffuse atmospheric-pressure RF glow discharge by this method with broadband UV absorption considering a number of rotational lines with J' ≤ 6.5, the detection limit of the line integrated OH(X) density with this method is of the order of 2 × 1019 m−2. The accuracy of the density is sensitive to the rotational temperature of the OH(A) state and the non-equilibrium rotational population distribution.

A two-dimensional array of micro-discharges in air at atmospheric pressure is studied by cross correlation spectroscopy (CCS) [1]. The array consists of two insulated metal meshes and the discharge is generated by AC voltages at 20 kHz. A gas flow is applied through the array. The temporal resolution of CCS in the sub-ns range allowed to investigate the micro-discharges dynamics within a single micro-discharge hole end-on.

In recent years, the measurement of absolute densities of reactive species and radicals such as OH is of growing interest for many plasma applications. Many complex techniques, including laser-induced fluorescence (LIF), cavity ring-down spectroscopy, resonant absorption and broadband absorption, have been used to measure absolute OH density. However, the optical emission spectroscopy (OES) has the natural advantage of being non-intrusive, inexpensive, and easy to implement, in comparison with the abovementioned methods.

Treefall gaps have been identified as important sites for plant recruitment. In this study, we compared seed rain between forest gaps and forest interior using 150 seed traps in the understory and 19 traps in gaps in a 24 ha permanent plot of subtropical evergreen broad-leaved forest in East China. We asked how total seed abundance and seed species richness, the relative representation of different dispersal modes, and seed limitation and its components differed between canopy gaps and the understory. Results showed that most of the species found in both the understory and in gaps were animal-dispersal, but most of the seed rain was comprised of wind-dispersed species in both habitats. No significant differences in either density or diversity of seeds between gaps and non-gap sites were found. Contrary to expectations, wind-dispersed seeds did not occur significantly more in treefall gaps than in the forest understory. There were also no significant differences in seed limitation and its components (source limitation, dispersal limitation) between the understory and gaps. Seed limitation was strong for all but a few of the best-dispersed species in both gap and understory seed traps. Source and dispersal limitation showed large inter-specific variation in both the understory and in gaps. Overall, our results indicate that: (i) gaps may play a neutral role in maintaining seed diversity in this subtropical forest; (ii) under strong seed limitation both in gaps and in the understory, population and community dynamics slows and ecological drift in species composition may become a more important determinant of community structure.

Extreme climatic events almost universally play a major role in influencing the composition and structure of plant and animal communities, and thus could influence seed production, seed dispersal and seedling recruitment. We explored the effects of ice storm damage on seed rain and seed limitation in a 24-ha permanent forest plot in an evergreen broad-leaved forest in east China. We compared seed production before and after the storm in 2008. We evaluated the following hypotheses: 1) seed production after the ice storm was less than that before the storm; 2) seed limitation after the storm was more severe than before the storm. The results showed that seeds from one species, Eurya muricata, dominated the seed rain after the storm, accounting for more than half of the total seeds. Post-ice storm seed production of species other than E. muricata was only one fifth of that before the storm. Seed production in the second year after the ice storm recovered to pre-storm levels. The results indicate large inter-specific variation in response to the ice storm. Disturbance caused by the ice storm greatly increased seed diversity. The Jaccard similarity of species before and after the ice storm was 58%. There was no significant difference in seed limitation or dispersal limitation before and after the storm, but there was a significant difference in source limitation. Neither seed limitation nor dispersal limitation was correlated with dispersal modes. Only source limitation for rodent dispersed species increased after the ice storm.

This study describes the dispersal phenology and syndromes in Gutianshan 24 ha plot in a subtropical broad-leaved forest of China. The 130 0.5 m 2 seed traps collected 69,115 mature seeds, representing 27 species (belonging to 24 genera, and 15 families) in 12 months. One marked peak in the number of seeds and species during the year was found in dry season (November). Zoochory was the most common dispersal syndrome (70.4%), followed by anemochory (18.5%), ballistic dispersal (11.1%). Among fruit types, berry (33%), capsule (22%), nut (18%), and drupe (11%) were common in the subtropical evergreen forest. In fruit color, brown was the commonest (40%), followed by dark brown (30%), black (15%), red (11%), and yellow (4%). Overall, the community level seed rain study revealed that one marked peak in seed number occurred in the middle of dry season; zoochory was the principal dispersal mode of woody plants in subtropical forest, and dry seasons favor seed dispersal by animal and wind.

The agricultural land suitability assessment based on the natural characteristics of land blocks is traditionally the basis for agricultural and/or land use planning. The assessment, however, is static and cannot be incorporated with potential land use changes. Recently, a dynamic approach, i.e., matter element analysis, has been effectively applied for land use planning. In the present study, based on matter element analysis, we established a matter element analysis model for land use suitability assessment using the suitability grade of land use, evaluation indicators and their characteristic values as matter elements, and also using sutra field, controlled field, weight value and correlation degree from field survey, as well as an expert system. This model was applied to the structure regulation of the land use in the small Yuejiagou watershed of the Langzhong Municipality in Sichuan Province, China. Results show that the proportion among agriculture, forestry and animal husbandry tended to rationalize land use. The economic and ecological indices of the lands were increased from 1529.8 to 1719.99 and from 1460.94 to 1758.21 after the regulation, respectively. The regulation also caused changes in landscape patterns as follows: The indices of diversity and evenness were increased from 1.3028 to 2.0920 and from 0.6108 to 0.8463, or by 60.58% and 38.56%, respectively. However, the indices of dominance and contagion were decreased from 0.6431 to 0.2106 and from 0.7467 to 0.7125, respectively. This indicated that the land use in the small watershed was rational. The spatial distribution of patches tended to be uniform. The patch congregation was gradually dispersed. This study verified that the matter element analysis approach can not only overcome the factitious influences and improve the precision of land assessment, but also can be used for the structure regulation of specific patches.

Seed mass and emergence time may influence fitness of plants. The experiments were conducted to investigate the effects of seed mass and emergence time on the performance of seedlings of Castanopsis chinensis, a large evergreen tree species with limited tolerance of shade. The treatment consisted of three light regimes: 100%, 15% and 2% of full sunlight. Germination rate and germination time showed a significant correlation with seed mass. Germination rate differed among the three light regimes. Early-emerging large-seeded seedlings in 100% light produced the heaviest seedlings, while those resulting from smaller late-emerging seeds and grown under 2% light regime produced the lightest seedlings. Relative growth rate (RGR) decreased with seed mass in all three light regimes, and seedlings of C. chinensis have a higher RGR in high and intermediate light levels compared to low light. In contrast, the effect of emergence time on RGR was not significant. The growth of C. chinensis seedlings were significantly influenced by seed size, emergence time, and light conditions. For each month, the mean height of seedlings was significantly greatest for large-seeded seedlings and significantly lowest for small-seeded ones, irrespective of emergence time and light conditions. Regeneration success of C. chinensis appears to be regulated by the interactive effect of seed mass, emergence time and light regime.

Epilepsy or seizure disorder is among the least understood chronic medical conditions affecting over 65 million people worldwide. Here, we show that disruption of the polycystic kidney disease 2-like 1 (Pkd2l1 or Pkdl), encoding polycystin-L (PCL), a non-selective cation channel, increases neuronal excitability and the susceptibility to pentylenetetrazol-induced seizure in mice. PCL interacts with β2-adrenergic receptor (β2AR) and co-localizes with β2AR on the primary cilia of neurons in the brain. Pkdl deficiency leads to the loss of β2AR on neuronal cilia, which is accompanied with a remarkable reduction in cAMP levels in the central nervous system (CNS). The reduction of cAMP levels is associated with a reduction in the activation of cAMP response element-binding protein, but not the activation of Ca(2+)/calmodulin-dependent protein kinase II, Akt or mitogen-activated protein kinases. Our data, thus, indicate for the first time that a ciliary protein complex is required for the control of neuronal excitability in the CNS.

BACKGROUND AND AIMS Autumn leaf senescence marks the end of the growing season in temperate ecosystems. Its timing influences a number of ecosystem processes, including carbon, water and nutrient cycling. Climate change is altering leaf senescence phenology and, as those changes continue, it will affect individual woody plants, species and ecosystems. In contrast to spring leaf out times, however, leaf senescence times remain relatively understudied. Variation in the phenology of leaf senescence among species and locations is still poorly understood. METHODS Leaf senescence phenology of 1360 deciduous plant species at six temperate botanical gardens in Asia, North America and Europe was recorded in 2012 and 2013. This large data set was used to explore ecological and phylogenetic factors associated with variation in leaf senescence. KEY RESULTS Leaf senescence dates among species varied by 3 months on average across the six locations. Plant species tended to undergo leaf senescence in the same order in the autumns of both years at each location, but the order of senescence was only weakly correlated across sites. Leaf senescence times were not related to spring leaf out times, were not evolutionarily conserved and were only minimally influenced by growth habit, wood anatomy and percentage colour change or leaf drop. These weak patterns of leaf senescence timing contrast with much stronger leaf out patterns from a previous study. CONCLUSIONS The results suggest that, in contrast to the broader temperature effects that determine leaf out times, leaf senescence times are probably determined by a larger or different suite of local environmental effects, including temperature, soil moisture, frost and wind. Determining the importance of these factors for a wide range of species represents the next challenge for understanding how climate change is affecting the end of the growing season and associated ecosystem processes.

The measurement of absolute densities of ubiquitous OH radicals and gas temperatures in water containing plasmas has recently drawn a lot of attention. In this paper, we extend the self-absorption model introduced in Du et al 2016 Plasma Sources Sci. Technol. 25 04LT02 with a description of the excited state by a superposition of two Boltzmann distributions to take the non-thermal rotational distribution of the excited state into account. This technique is applied to a diffuse He + H2O RF discharge and it is shown that in addition to the determination of the ground state OH density and rotational temperature, the properties of the excited state OH(A) can also be simultaneously determined. A model of the steady-state distribution of the hot and cold group density of OH(A) is able to describe the dependence of the rotational population distributions of the excited state as a function of the water concentration. The method is also applied to a filamentary Ar + H2O DBD. While the non-homogeneous nature of the DBD leads to complications, the production of OH(A) by multiple production mechanisms leading to a complex nascent rotational population distribution causes the fitting procedure of the emission spectrum (with self-absorption) to break down.

The micro-discharge properties and evolution in a 2D array of integrated coaxial microhollow dielectric barrier discharges are studied by using highly time-resolved electrical and optical diagnostics. The study is focused on the effect of the gas flow rate and gas residence time on discharge properties. The investigated integrated coaxial microhollow discharge geometry allows operating the discharge at exceptionally small residence times, which can be equal to or even smaller than the discharge period, at reasonable gas flow rates. The gas flow has an impact on gas heating, residual humidity, pre-ionization density and the densities of excited and reactive species produced by previous discharges. A unique voltage–charge plot is obtained with elongated periods without discharge activity. A very significant effect of flow on NO emission is observed that relates to the impact of flow on the NO production in these micro-discharges. Using the emission intensities of molecular bands of the second positive system of nitrogen and the first negative system of the nitrogen ion, effective reduced electric field strengths are obtained with a maximum equal to 870 Td. The reduced electric field decreases with increasing gas flow rate. This behavior is consistent with the reduction of the overall discharge intensity due to a reduced amount of charges present in the discharge gap. Both the flow rate and a reduction in water impurity changing the ion mobility can be responsible for the different effective electric field distributions at the highest and no flow conditions.

The Alzheimer's disease model in Wistar rats was established by injection of amyloid β-peptide (Aβ1–42) into the hippocampal CA1 region. Rats were treated with suspended moxibustion on Baihui (GV20) and Shenshu (BL23) acupoints. Prior to and post Aβ1–42 exposure. Results showed no evidence of apoptosis in hippocampal neurons, a significantly reduced apoptosis rate of neurons and improved learning and memory abilities were observed in the Alzheimer's disease model. In particular, moxibustion prior to Aβ1–42 exposure was more effective than moxibustion after Aβ1–42 exposure in protecting the neuronal structure and lowering the apoptosis rate. Our findings indicate that a combination of preventive and therapeutic moxibustion has a beneficial effect for the prevention of Alzheimer's disease development.

Distribution of messenger RNA (mRNA) encoding the insulin-like growth factor (IGF) type 2 receptor (IGF2R) is investigated in the rat lower brainstem by in situ hybridization histochemistry. Cells with IGF2R mRNA are distributed widely in a region-specific manner. It is expressed in: (1) motor nuclei such as the oculomotor nucleus, trochlear nucleus, motor trigeminal nucleus, abducens nucleus, facial nucleus, ambiguus nucleus, dorsal motor nucleus of vagus and hypoglossal nucleus; (2) several sensory-related nuclei like the mesencephalic trigeminal nucleus, ventral nucleus of the lateral lemniscus, lateral and spinal vestibular nuclei, ventral and dorsal cochlear nuclei and nucleus of the trapezoid body; and (3) other regions such as the red nucleus, dorsal raphe nucleus, pontine nuclei, three cerebellar nuclei (medial, interposed and lateral), Purkinje cells, cells in the granular layer of the cerebellum, locus coeruleus, several areas of the reticular nucleus and area postrema.

The effect of self-absorption on emission intensity distributions can be used for species concentration measurements. A calculation model is developed based on the Beer-Lambert law to quantify this effect. And then, a calibration-free measurement method is proposed on the basis of this model by establishing the relationship between gas concentration and absorption strength. The effect of collision parameters and rotational temperature on the method is also discussed. The proposed method is verified by investigating the nitric oxide emission bands (A²Σ⁺→X²∏) that are generated by a pulsed corona discharge at various gas concentrations. Experiment results coincide well with the expectations, thus confirming the precision and accuracy of the proposed measurement method.