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Widespread surveys of avian haemosporidia (Plasmodium, Haemoproteus, and Leucocytozoon) in wild birds have substantially advanced information on the haemosporidian fauna of Japan. However, many areas and bird species remain insufficiently investigated. Bird carcasses collected for personal specimen collection seldom reach academic audience particularly in the veterinary field. The presence of avian haemosporidia was investigated in these personally collected bird carcasses, in order to better understand the avian haemosporidian fauna in Japan. Bird carcasses were donated through personal contact upon approval of the study. Tissue samples were collected from the birds and examined for haemosporidian parasites using nested-PCR targeting the cytochrome b gene. One hundred and forty-three birds of 85 species were donated, including 34 species and two subspecies that were molecularly or collectively investigated for the first time in Japan. Avian haemosporidian DNA was detected from 37 of the 134 tested birds (27.61%). In 8 bird species, avian haemosporidia was detected for the first time. Twenty-nine lineages were detected, including 8 novel and 9 known lineages detected in Japan for the first time. Furthermore, 16 lineages were detected from novel host species. While information that could be drawn was limited and risk management of zoonotic diseases needs re-consideration, these findings expanded information on the host range and distribution of several lineages. Collectively, this method of investigation using personally collected bird samples can provide important additions to more fully understand the avian haemosporidian fauna of Japan, as well as other areas with limited investigations.

The nitrogen deficiency in steels measured by atom probe tomography (APT) is considered to arise from the obscurement of singly charged dimer nitrogen ions (N2+) by the iron-dominant peak (56Fe2+) at 28 Da. To verify this by quantifying the amount of N2+ ions, γ′-Fe4N consisting of the 15N isotope was prepared on iron substrates by plasma nitriding using a nitrogen isotopic gas (15N2). Although considerable amounts of 15N2+ were observed at 30 Da without overlap with any iron peak, the observed nitrogen concentrations of γ′-Fe4N were clearly lower than the stoichiometric composition (19–20 at%), using both pulsed voltage and pulsed laser atom probes. The origin of the missing nitrogen, excluding nitrogen obscured by other ion species, was predicted to be the occurrence of neutral nitrogen or nitrogen gas molecules in field evaporation. The generation rate of iron nitride ions (FeN2+) for 15N was significantly lower than that for 14N in γ′-Fe4N, which affected the amount of the missing nitrogen. The isotope effect suggests that the isotopic ratio cannot always be determined from only one ion species among the multiple species observed in the APT analysis. We discuss the mechanism of the isotope effect in FeN2+ formation by field evaporation.

The carbon (C) ratios, namely the atomic ratios of C/(C + M), in nano-sized coherent MC precipitates (M = Ti, Nb) with the NaCl-type (B1) structure in ferritic steels, which had been isothermally aged at 580 °C, were investigated using atom probe tomography (APT). Considering the influences of the trajectory aberration, detection loss, and peak overlap, we determined the C ratios to be ~0.40 and ~0.45 for an equivalent volume diameter of 1.5–5 nm and 1–5 nm for the TiC and NbC precipitates, respectively, suggesting that there is a considerable fraction of C vacancies in both nano-sized precipitates. The apparent C ratios show significant scatter with decreasing particle size, while the apparent mean C ratios of very fine TiC particles, smaller than 1.5 nm, decreased with decreasing particle size. With the use of one of the latest APT instruments with a high detection efficiency, the scattering in the apparent C ratios was reduced because the counting statistics were improved; however, the artificial enrichment of C atoms to particular crystallographic directions of ferrite hindered the determination of the C ratio for very fine TiC particles smaller than 1.5 nm.

The quantitative analysis performance of carbon and nitrogen was investigated using stoichiometric θ-Fe3C (25 at% C) and γ′-Fe4N (~20 at% N) precipitates in pulsed voltage and pulsed laser atom probes. The dependencies of specimen temperature, pulse fraction, and laser pulse energy on the apparent concentrations of carbon and nitrogen were measured. Good coincidence with 25 at% carbon concentration in θ-Fe3C was obtained for the pulsed voltage atom probe by considering the mean number of carbon atoms per ion at 24 Da and the detection loss of iron, while better coincidence was obtained for the pulsed laser atom probe by considering only the mean number of carbon at 24 Da. On the other hand, a lack of nitrogen concentration in γ′-Fe4N was observed for the two atom probes. In particular, the pulsed laser atom probe showed a significant lack of nitrogen concentration. This implies that a large amount of 14N2+ was obscured by the main iron peak of 56Fe2+ at 28 Da in the mass-to-charge spectrum. Regarding preferential evaporation or retention, carbon in θ-Fe3C exhibited little of either, but nitrogen in γ′-Fe4N exhibited definite preferential retention. This result can be explained by the large difference in ionization energy between carbon and nitrogen.

The nitrogen deficiency in steels measured by atom probe tomography (APT) is considered to arise from the obscurement of singly charged dimer nitrogen ions (N2+) by the iron-dominant peak (56Fe2+) at 28 Da. To verify this by quantifying the amount of N2+ ions, γ′-Fe4N consisting of the 15N isotope was prepared on iron substrates by plasma nitriding using a nitrogen isotopic gas (15N2). Although considerable amounts of 15N2+ were observed at 30 Da without overlap with any iron peak, the observed nitrogen concentrations of γ′-Fe4N were clearly lower than the stoichiometric composition (19–20 at%), using both pulsed voltage and pulsed laser atom probes. The origin of the missing nitrogen, excluding nitrogen obscured by other ion species, was predicted to be the occurrence of neutral nitrogen or nitrogen gas molecules in field evaporation. The generation rate of iron nitride ions (FeN2+) for 15N was significantly lower than that for 14N in γ′-Fe4N, which affected the amount of the missing nitrogen. The isotope effect suggests that the isotopic ratio cannot always be determined from only one ion species among the multiple species observed in the APT analysis. We discuss the mechanism of the isotope effect in FeN2+ formation by field evaporation.

The influence of a pre-deformation with a true strain of 0.5 on the precipitation behavior during isothermal aging at 580 °C in ferritic steel containing 0.03C-0.1Ti-0.20Mn–3Al (mass %) was investigated. Atom probe tomography (APT) analysis revealed that titanium carbide (TiC) precipitates much earlier and more finely in pre-deformed steel than in steel without a pre-deformation. It was found that the precipitation sites of TiC are not only located on the dislocations but are also distributed homogeneously in a matrix in pre-deformed steel. In steel without a pre-deformation, coarse cementite first precipitates during the early stage of aging, and the cementite then dissolves owing to the subsequent precipitation of TiC. Meanwhile, in pre-deformed steel, cementite has difficulty precipitating, and carbon atoms are considered to segregate to high-density dislocations during the early stage of aging prior to the precipitation of TiC. A kinetic model that explains the difference between the precipitation behaviors of steel with and without a pre-deformation is proposed. Moreover, the difference observed between TiC particle strengthening in steel with and without a pre-deformation is discussed.

Cr- and Cu-added steel sheets enable hardening of the surface region (the diffusion layer) by nitriding and simultaneously strengthening of the inner region due to thermally activated Cu precipitation during nitriding. Atom probe tomography (APT) analysis revealed that precipitate pairs, each composed of a Cu particle and CrN particle, were generated in the nitrided surface region. The influence of the complex precipitation of Cu and CrN on the precipitation kinetics and hardening properties was investigated by experimentally varying the initial state of Cu atoms in the steel by pre-aging before nitriding. It was found that Cu particles and CrN particles acted as heterogeneous nucleation sites for CrN and Cu, respectively, and the complex precipitation adversely affected the hardening of the nitrided surface region depending on the initial state of Cu. In addition, it was found that there were two types of precipitate pair forms (type-A/B), which were considered to be determined by the relation between the {001}-facet-size of the Cu particle and the size of the CrN nucleus in heterogeneous nucleation.

Seed retention time (SRT), the time interval between seed ingestion and defaecation, is a critical parameter that determines the spatial pattern of seed dispersal created by an animal, and is therefore, an essential component of trait‐based modelling of seed dispersal functions. However, no simple predictive model of SRT for any given animal exists. We explored the linkage between animal traits and SRT. We collected previously published data on mean SRT for 112 species of birds, mammals, reptiles and fishes and investigated the general allometric scaling of mean SRT with body mass for each taxon. Moreover, we analysed the effects of food habit and digestive strategy on mean SRT for birds and mammals. In general, mean SRT increased with body mass in all four taxa, whereas the pattern of allometric scaling varied greatly among the taxa. Birds had a smaller intercept and larger slope than those of mammals, whereas reptiles had a much larger intercept and smaller slope than those of either birds or mammals. For birds, food habit was also detected as an important factor affecting SRT. We applied the allometric scaling that was obtained for birds to estimate mean SRT of extinct Mesozoic dinosaurs (Theropoda) – few of which are assumed to have acted as seed dispersers. SRT for large carnivorous theropods was estimated to be 4–5 days, when considering only body mass. The present study provides allometric scaling parameters of mean SRT for a variety of seed‐dispersing animals, and highlights large variations in scaling among taxa. The allometric scaling obtained could be a critical component of further trait‐based modelling of seed dispersal functions. Further, the potential and limitations of the scaling of animal SRT with body mass and a future pathway to the development of trait‐based modelling are discussed.

The quantitative analysis performance of carbon and nitrogen was investigated using stoichiometric θ-Fe3C (25 at% C) and γ'-Fe4N (~20 at% N) precipitates in pulsed voltage and pulsed laser atom probes. The dependencies of specimen temperature, pulse fraction, and laser pulse energy on the apparent concentrations of carbon and nitrogen were measured. Good coincidence with 25 at% carbon concentration in θ-Fe3C was obtained for the pulsed voltage atom probe by considering the mean number of carbon atoms per ion at 24 Da and the detection loss of iron, while better coincidence was obtained for the pulsed laser atom probe by considering only the mean number of carbon at 24 Da. On the other hand, a lack of nitrogen concentration in γ'-Fe4N was observed for the two atom probes. In particular, the pulsed laser atom probe showed a significant lack of nitrogen concentration. This implies that a large amount of 14N2+ was obscured by the main iron peak of 56Fe2+ at 28 Da in the mass-to-charge spectrum. Regarding preferential evaporation or retention, carbon in θ-Fe3C exhibited little of either, but nitrogen in γ'-Fe4N exhibited definite preferential retention. This result can be explained by the large difference in ionization energy between carbon and nitrogen.

We successfully achieved atomic scale visualization of hydrogen atoms at trapping sites associated with the nano-sized precipitates of titanium carbide and vanadium carbide in ferritic steels using a modified three-dimensional atom probe with a deuterium charge cell. We proposed that the hydrogen trapping sites of fine carbide precipitates were at the (001) broad interface between the precipitate and the ferrite matrix. In this study, the precipitate size dependence in the trapping site and its energy was systematically investigated in vanadium carbide precipitation strengthening steels with various aging times. Hydrogen thermal desorption spectrometry analysis showed that the hydrogen trapping energy in the peak- and over-aged steels was larger than that in the under-aged steel. Atom probe tomography analysis showed the {001} platelets of vanadium carbide were covered by charged deuterium atoms in the peak-aging steel with large trapping energy, whereas no deuterium atoms around the {001} platelets were observed in the under-aged steel with small trapping energy. High-resolution transmission electron microscopy observation showed that misfit dislocations hardly appeared on the (001) surface of the precipitates in the two steels with large and small trapping energies. In contrast, the vanadium–carbon atomic ratios of vanadium carbide precipitates were definitely different between the two steels with large and small trapping energies. The precipitates in the under-aged steel with small trapping energy showed a chemical composition similar to VC, whereas the precipitates in the peak- and over-added steels with large trapping energy showed a chemical composition similar to V4C3. These results suggested that the origin of the hydrogen trapping site with large trapping energy is not the misfit dislocation core but the carbon vacancy on the (001) broad surface of V4C3 precipitates.

Puffinus lherminieri bannermani is a small black-and-white shearwater, which is endemic to the Ogasawara Islands, Japan. The taxonomic position of this shearwater is contentious. It is treated as a subspecies of Audubon's Shearwater P. lherminieri or the Tropical Shearwater P. bailloni in some checklists, while it is as considered monotypic, as Bannerman's Shearwater P. bannermani, in others. We examined the mitochondrial cytochrome b region to determine the taxon's phylogenetic position. While on the one hand the results showed that it was not genetically related to either P. lherminieri or P. bailloni, but formed a clade with P. myrtae, P. newelli, and P. auricularis, on the other hand, bannermani has diverged substantially from the other three taxa in both genetic and morphological features. This shearwater was first described as Bannerman's Shearwater, and our results confirm that P. lherminieri bannermani should be split from Audubon's Shearwater, and the monotypic Bannerman's Shearwater is ...

It was reported by the thermal desorption analysis (TDA) of hydrogen that bainite–austenite dual-phase steels showed two activation energies of ~30 kJ/mol and ~ 47 kJ/mol under low- and high-fugacity conditions, respectively, and the latter energy corresponded to hydrogen diffusion in austenite; however, the hydrogen trap sites of the former energy were unclear (Sekine et al., 2019, 2018 [ 1 , 2 ]). The hydrogen trap sites under the low-fugacity condition in the steel were investigated by directly observing deuterium-charged specimens using atom probe tomography (APT). The charged deuterium atoms were distributed in carbon-rich regions of the fine irregular structure in the bainite region of the steel. The carbon concentrations in these region were in the range of 12–20 at.% without enrichment of other alloying elements. The diffraction analysis with transmission electron microscopy (TEM) indicated the presence of a substantial amount of fine precipitates of epsilon carbide in the bainite region of the steel. Hence, the hydrogen trap sites were considered to be associated with fine precipitates of epsilon carbide (e-carbide) with carbon compositions marginally lower than the stoichiometric composition. First principles calculations suggested that the hydrogen trap sites in the steel originated from the carbon vacancies in the surface region of e-carbide.

The addition of small amount of boron (B) to steels has been found to significantly increase the hardenability of steels during cooling. This is further increased by the addition of molybdenum (Mo) and the combined addition of both. To clarify the mechanism of the Mo-B combined addition effect, quantitative analysis of segregating atoms at prior austenite grain boundaries in B- and Mo-added low-carbon (C) steels was performed using atom probe tomography. The dependences of Mo content and cooling rate on the amounts of B and Mo segregations were systematically investigated in the steels with austenizating temperature of 950 °C. The amount of B segregation at the prior austenite grain boundary was mostly independent of Mo content at a high cooling rate of 30 °C/s. In contrast, at a low cooling rate of 5 °C/s, the amount of B segregation increased in the B-added steel with Mo, and decreased without Mo, whereas the amount of Mo segregation increased with increasing Mo content and with lowering cooling rate. Such segregation behaviors of B and Mo were explained by the diffusion limited equilibrium segregation and precipitation of Fe 23 (CB) 6 at the austenite grain boundary. We discussed the influence of B and Mo segregations on hardenability from the relation between hardenability index and actual segregation amount in the steels.

The difference in quantitative analysis performance between the voltage-mode and laser-mode of a local electrode atom probe (LEAP3000X HR) was investigated using a Fe-Cu binary model alloy. Solute copper atoms in ferritic iron preferentially field evaporate because of their significantly lower evaporation field than the matrix iron, and thus, the apparent concentration of solute copper tends to be lower than the actual concentration. However, in voltage-mode, the apparent concentration was higher than the actual concentration at 40K or less due to a detection loss of matrix iron, and the concentration decreased with increasing specimen temperature due to the preferential evaporation of solute copper. On the other hand, in laser-mode, the apparent concentration never exceeded the actual concentration, even at lower temperatures (20K), and this mode showed better quantitative performance over a wide range of specimen temperatures. These results indicate that the pulsed laser atom probe prevents both detection loss and preferential evaporation under a wide range of measurement conditions.

The Oriental greenfinch

The nominotypical subspecies of the Eastern buzzard (

It is well known that niobium in solute solution retards the recovery of dislocations in steel. Segregation of niobium atoms to dislocations was observed for the first time by atom probe tomography in niobium added ferritic stainless steels for high temperature use. The observation results suggest that solute niobium atoms solely have strong attractive interaction with dislocations. We name it niobium-Cottrell atmosphere, and discuss the trapping site and interaction energy through a comparison with segregation to the grain boundary in the same steel.

Partitioning of Cr and Si between cementite and ferrite was investigated by first-principles thermodynamics taking into account vibrational, electronic, and magnetic Gibbs energy contributions. At finite temperatures, these contributions lower the partitioning Gibbs energy and compete with the configurational entropy, which favors impurity segregation to ferrite due to its larger volume fraction compared to cementite. Due to the large positive partitioning enthalpy contribution of Si at T = 0 K, partitioning of Si to cementite is virtually absent in agreement with experiment. The situation is drastically different for Cr impurities. Incorporation of finite-temperature effects resolves the discrepancy between experimental observations and previous T = 0 K first-principles calculations. Cr strongly segregates to cementite due to the enhanced magnetic entropy of cementite above 400 K, i.e., near the Curie temperature of cementite. The increasing magnetic fluctuations in ferrite cause a strong reduction of the partitioning coefficient in the temperature range from 773 to 973 K in qualitative agreement with experiment. Quantitative agreement with calphad data and experimental data for equilibrium Cr concentrations in a wide range of alloy compositions is achieved by renormalizing the theoretical magnetic partitioning Gibbs energy by a constant scaling factor.

The Oriental greenfinch, Chloris sinica, is a small seed-eating finch that breeds in the eastern Palearctic region, an area that spans from Russia in the east to China, Korea, and Japan in the south and southwest. Several subspecies have been described based on subtle morphological characteristics, although the taxonomy varies among different authors. Although many ecological studies have been performed, there has been no phylogenetic study that encompasses the species' entire geographical range. We used four regions of mitochondrial DNA to analyze the intraspecies genetic phylogeny and diversity of the Oriental greenfinch. In addition, we performed morphometric analyses using museum specimens. Genetic analysis identified two clades that diverged approximately 1.06 million years ago. These were a population from the Ogasawara Islands, Japan (subspecies kittlitzi, Clade B), and the other populations (Clade A, which could not be subdivided according to geographic context). Morphometric analyses showed that the population on the Kuril Islands (subspecies kawarahiba) had the longest mean wing length, whereas C. s. kittlitzi had the shortest wings. Chloris s. kittlitzi also had the longest mean bill length, probably because it has adapted to feeding on the Ogasawara Islands. Based on molecular phylogeny and morphology analyses, we recommend that C. s. kittlitzi should be treated as a completely distinct species, called the Ogasawara greenfinch, Chloris kittlitzi. It is critically endangered and needs to be specially protected.

The eradication of dominant, nonnative trees can alter soil conditions in forest ecosystems by changing the forest's water balance. To test this idea, we measured water in surface soil in forests dominated by an invasive nonnative tree (Casuarina equisetifolia Forst.) on Nishijima Island, a subtropical island in the Ogasawara Islands group, northwestern Pacific Ocean. The volumetric water content of surface soils at sites where all trees of C. equisetifolia were killed by herbicide was compared with adjacent invaded control sites, and effects of time since tree removal (up to 3 yr) were assessed. Dry weights of accumulated litter, total canopy openness of the forest canopy, maximum heights, and total plant cover of herbaceous vegetation were also compared between treatment and control plots. Volumetric soil water content in quadrats where C. equisetifolia trees were removed (removal area) was significantly higher than at control quadrats. We found that the effect of C. equisetifolia removal on s...

SummaryThe East Asian-Australasian Flyway supports the greatest diversity and populations of migratory birds globally, as well as the highest number of threatened migratory species of any flyway, including passerines (15 species). However it is also one of the most poorly understood migration systems, and little is known about the populations and ecology of the passerine migrants that breed, stop over and winter in the habitats along this flyway. We provide the first flyway-wide review of diversity, ecology, and conservation issues relating to 170 species of long-distance and over 80 short-distance migrants from 32 families. Recent studies of songbird migration movements and ecology is limited, and is skewed towards East Asia, particularly Mainland China, Taiwan, Russia, Japan and South Korea. Strong evidence of declines exists for some species, e.g. Yellow-breasted Bunting Emberiza aureola, but tends to be fragmentary, localised or anecdotal for many others. More species have small breeding ranges (< 250,000 km2) and/or are dependent on tropical forests as wintering habitat than those in any other Eurasian migratory system, and are thus more vulnerable to habitat loss and degradation throughout their ranges. Poorly regulated hunting for food and the pet trade, invasive species and collisions with man-made structures further threaten migratory songbirds at a number of stop-over or wintering sites, while climate change and habitat loss may be of increasing concern in the breeding ranges. A key conservation priority is to carry out intensive field surveys across the region while simultaneously tapping into citizen science datasets, to identify important stop-over and wintering sites, particularly for poorly-known or globally threatened species across South-East Asia and southern China for targeted conservation actions. Additionally, the advent of miniaturised tracking technology, molecular and isotopic techniques can provide novel insights into migration connectivity, paths and ecology for species in this migration system, complementing data from banding exercises and observation-based surveys, and could prove useful in informing conservation priorities. However, until most states along the East Asian-Australasian flyway ratify the Convention on the Conservation of Migratory Species of Wild Animals (CMS) and other cross-boundary treaties, the relative lack of cross-boundary cooperation, coordination and information sharing in the region will continue to present a stumbling block for effective conservation of migratory passerines.