Showing papers on "Heron published in 2023"

Effects of Rice Field Water Cycles on the Breeding Biology of Grey Heron (Ardea cinerea) and Conservation Implications

Abstract: Abstract. Wetlands are among the most threatened ecosystems on the planet, largely due to their conversion to agricultural or dry land. L'Albufera de Vàlencia is characterized by a large expanse of rice fields (c. 14,000 ha), which hosts the most important colony of Grey Heron Ardea cinerea on the Mediterranean coast of Spain. The colony was visited every 10 days during February-April of 2016 to 2018 and during May-July of 2015 to 2017. The reproductive parameters were estimated for each year and season. We also monitored the available habitat and habitat use of the species in the rice fields from February 2016 to June 2017. The condition of the rice field was related to reproductive parameters. The breeding period was divided into two stages per year. In 2016 all reproductive parameters were lower values, coinciding with a larger area of dry fields in winter and low rainfall in summer. Breeding success was found to be positively associated with the muddy/semi-flooded fields and negatively associated with the sown fields. Like Grey Heron, other waterbirds species nesting in L'Albufera de Valencia could depend on the condition of the rice fields for breeding success. Their reproductive requirements should be considered in rice cultivation management.

Vocal Activity of Little Bittern (Ixobrychus m. minutus) during the Breeding Season

Abstract: Abstract. Heron vocalization and its behavioral functions are one of the least researched aspects of heron biology. The main aim of this study was to investigate the patterns of seasonal and daily vocal output of male Little Bittern (Ixobrychus m. minutus; n = 8) during the breeding season (May–August). The advertising call started on 10th May, and finished on 28th July. The first peak of calling activity occurred between 21st May and 1st June, and the second one was between 14th June and 7th July. The daily vocal activity fluctuated and depended on the time of day. The males were most active between 0300–0900 hours and 1600–2200 hours, with the highest peaks in vocal output occurring before sunrise and before sunset. Higher vocal activity was observed in the evening compared to the morning hours. Moreover, the vocal activity of males was not related to air temperature.

Ultraconserved elements resolve the phylogeny and corroborate patterns of molecular rate variation in herons (Aves: Ardeidae)

Abstract: ABSTRACT Thoroughly sampled and well-supported phylogenetic trees are essential to taxonomy and to guide studies of evolution and ecology. Despite extensive prior inquiry, a comprehensive tree of heron relationships (Aves: Ardeidae) has not yet been published. As a result, the classification of this family remains unstable, and their evolutionary history remains poorly studied. Here, we sample genome-wide ultraconserved elements (UCEs) and mitochondrial DNA sequences (mtDNA) of >90% of extant species to estimate heron phylogeny using a combination of maximum likelihood, coalescent, and Bayesian inference methods. The UCE and mtDNA trees are mostly concordant with one another, providing a topology that resolves relationships among the 5 heron subfamilies and indicates that the genera Gorsachius, Botaurus, Ardea, and Ixobrychus are not monophyletic. We also present the first genetic data from the Forest Bittern Zonerodius heliosylus, an enigmatic species of New Guinea; our results suggest that it is a member of the genus Ardeola and not the Tigrisomatinae (tiger herons), as previously thought. Finally, we compare molecular rates between heron clades in the UCE tree with those in previously constructed mtDNA and DNA–DNA hybridization trees. We show that rate variation in the UCE tree corroborates rate patterns in the previously constructed trees—that bitterns (Ixobrychus and Botaurus) evolved comparatively faster, and some tiger herons (Tigrisoma) and the Boat-billed Heron (Cochlearius) more slowly, than other heron taxa. LAY SUMMARY We use genetic data from across the genome and produce a robust family tree for herons, which clarifies the relationships among subfamilies and genera. A comprehensive phylogeny of herons is lacking. As a result, their taxonomy is unstable and their evolutionary history is poorly known. Several species were found to be incorrectly classified, and we recommend appropriate taxonomic revisions. Comparisons of molecular evolution support previous studies. Bitterns have evolved comparatively faster, with some tiger herons and the Boat-billed Heron having evolved comparatively slower. RESUMEN Los árboles filogenéticos cuidadosamente muestreados y bien respaldados son esenciales para la taxonomía y para guiar los estudios de evolución y ecología. A pesar de una extensa investigación previa, aún no se ha publicado un árbol completo de las relaciones de las garzas (Aves: Ardeidae). Como resultado, la clasificación de esta familia sigue siendo inestable y su historia evolutiva sigue siendo poco estudiada. Aquí, tomamos muestras de elementos ultraconservados (EUCs) de todo el genoma y secuencias de ADN mitocondrial (ADNmt) de >90% de las especies existentes para estimar la filogenia de las garzas usando una combinación de métodos de máxima verosimilitud, coalescencia e inferencia bayesiana. Los árboles de EUC y ADNmt son en su mayoría concordantes entre sí, lo que proporciona una topología que resuelve las relaciones entre las cinco subfamilias de garzas e indica que los géneros Gorsachius, Botaurus, Ardea e Ixobrychus no son monofiléticos. También presentamos los primeros datos genéticos de Zonerodius heliosylus, una enigmática especie de Nueva Guinea; nuestros resultados sugieren que es un miembro del género Ardeola y no de Tigrisomatinae (garzas tigre), como se pensaba anteriormente. Por último, comparamos las tasas moleculares entre los clados de garzas en el árbol de EUC con aquellas de los árboles de ADNmt y de hibridación ADN–ADN construidos previamente. Mostramos que la variación de las tasas en el árbol de EUC corrobora los patrones de las tasas en los árboles construidos previamente—que Ixobrychus y Botaurus evolucionaron comparativamente más rápido y algunas garzas tigre (Tigrisoma) y Cochlearius más lento que otros taxones de garzas.

Macroscopic and microscopic comparison of pecten oculi in different avian species.

Abstract: The current study aims to present differences between the pecten oculi of different avian species through morphologic, macroscopic, light, and electron microscopic examinations. The study is a comprehensive research on seven avian species (sparrowhawk, hawk, magpie, swan, heron, pheasant, duck). The right eyes of the animals utilized in the study were removed for light microscopic examination, whereas their left eyes were removed for electron microscopic and macroscopic examinations. Morphometric analyses, as well as stereo and light microscopic measurements, were carried out on the pecten oculi of the animals. Given all these data, it was determined that the height of the pecten oculi did not differ among the species in the study; however, the pecten oculi were larger in birds with the highest value compared to the other species in the macroscopic measurements. Also, the pecten oculi vessels were larger, and the number of melanocytes was higher in keen eyesight, raptor, and migratory birds with large bulbus oculi. All these data suggest that the pecten oculi not only supplies nutrient to the retina but also contributes to sharp vision during migration and hunting, UV absorption from sunlight, as well as preservation of intraocular equilibrium.

“A white heron” by Sarah Orne Jewett: ecocritical interpretation

Abstract: International scientific conference «Innovative aspects of the development of philological sciences» : conference proceedings (April 5–6, 2023. Częstochowa, the Republic of Poland). Riga, Latvia : «Baltija Publishing», 2023. 216 pages.

Eudora Welty's "A Still Moment" and Sarah Orne Jewett's "A White Heron"

Abstract: Eudora Welty's "A Still Moment" and Sarah Orne Jewett's "A White Heron" Anna E. Beaudry (bio) A hunter and a heron unite Eudora Welty's "A Still Moment" and Sarah Orne Jewett's "A White Heron." Joseph Rosenblum notes similarities in plot and focuses on the "mystical experience with the heron" that both stories share (72). Thomas L. McHaney and Peter Schmidt have acknowledged Welty's debt of influence to Jewett and other female regionalists, and Helen Fiddyment Levy makes a passing connection between the stories. Nonetheless, little has been done to consider the ecocritical possibilities that the stories have in common: firstly, the posture towards nature that each author seems to advocate for involves a kind of curative hybridity. By hybridity, I mean a blending of the human and more-than-human that serves as an antidote to the symptoms of modernity's ills, like consumerism and progressivism. Secondly, these stories share an invitation to engage in intimacy with nature and place. The hunter and the heron are the most obvious links between the stories, but these figures carry a particularly ecocritical weight as well. The hunter in Jewett's story is intentionally modeled after John James Audubon, while the hunter in Welty's story is Audubon. In each story, the bird depicted is the Snowy Egret, a small white heron, mislabeled Snowy Heron or White Egret in Audubon's iconic painting. This heron became the subject of national attention when it was hunted to near extinction in the late nineteenth century due a ladies' millinery craze involving the bird's remarkable breeding plumage. According to the famous ornithologist-artist Roger Tory Peterson, Snowy Egret plumes "were worth $32 an ounce, twice their weight in gold"; the high demand for these plumes led to "[e]very heronry [being] ferreted out and destroyed. … Where there had been hundreds of thousands [End Page 151] of egrets in our southern states there soon remained but a few hundred."1 In order to bring awareness to the crisis, Jewett's story transplants the heron away from its home in southern marshes to the Maine coastline, despite the fact that the bird rarely is found further north than Massachusetts. "A White Heron" lends itself, as many of Jewett's works do, to an ecocritical reading of her fiction. Welty, by contrast, returns the bird to its natural habitat, setting her narrative in the Natchez Trace, Mississippi. Welty's choice of the heron is an interesting one; Diana R. Pingatore, in her guide to Welty's short fiction, draws attention to Welty's close adherence to source texts for the three men who appear in "A Still Moment," all of whom are based upon historic persons. Albert Devlin has a 1977 note on a possible source for the heron, a vision of a white horse recorded by one of Murrell's fellow outlaws (64). In a 1965 interview with Welty that confirms Devlin's theory, she mentions this vision specifically ("An Interview" 22). What neither Devlin nor Pingatore reflects upon, however, is why a heron? On one level, a bird makes sense to include with the figure of Audubon, but why that particular species? Considering the significance of the white heron in Jewett's short fiction, Jewett's heron serves as a likely inspiration for Welty, and, considering the precarious history of the bird, perhaps even as a source for Welty's ecocritical bent as well.2 As Rosenblum notes, "both stories begin at sunset," a liminal time of day where shadows and ghosts alike walk in deep glades in the fading light (70). The sun sets over each story's respective wilderness: the Maine woods and the Natchez Trace. Neither story romanticizes the wilderness. Instead, the twilight setting of each story creates a sense of unease and anxiety in the reader and not without reason. The wilderness is a place where anything can happen for good or ill. Heightening this tension, both Welty and Jewett employ Gothic or folklore tropes throughout each tale, setting an uncanny mood. As Elizabeth Ammons and Sarah Way Sherman have noted, Jewett relies heavily on fairytale tropes, drawing specifically on "Little Red Riding [End Page 152] Hood...

Improving the metric of surgical freedom in the laboratory based on a novel concept of volume

Abstract: In laboratory-based neuroanatomical studies, surgical freedom, the most important metric of instrument maneuverability, has been based on Heron's formula. Inaccuracies and limitations hinder this study design's applicability. A new methodology, volume of surgical freedom (VSF), may produce a more realistic qualitative and quantitative representation of a surgical corridor.Overall, 297 data set measurements assessing surgical freedom were completed for cadaveric brain neurosurgical approach dissections. Heron's formula and VSF were calculated specifically to different surgical anatomical targets. Quantitative accuracy and the results of an analysis of human error were compared.Heron's formula for irregularly shaped surgical corridors resulted in overestimation of the respective areas (minimum overestimation 31.3%). In 92% (188/204) of data sets reviewed for influence of offset, areas calculated on the basis of measured data points were larger than areas calculated on the basis of the translated best-fit plane points (mean [SD] overestimation of 2.14% [2.62%]). Variability in the probe length attributable to human error was small (mean [SD] calculated probe length 190.26 mm [5.57 mm]).VSF is an innovative concept that can develop a model of a surgical corridor producing better assessment and prediction of the ability to maneuver and manipulate surgical instruments. VSF corrects for deficits in Heron's method by generating the correct area for an irregular shape using the shoelace formula, adjusting the data points to account for offset, and attempting to correct for human error. VSF produces 3-dimensional models and, therefore, is a preferable standard for assessing surgical freedom.

Distance sampling with vehicle-mounted cameras for the estimation of farmland bird abundance over a wide area

Abstract: Agricultural birds are declining due to farmland abandonment and agricultural intensification, and monitoring approaches, including efficient survey methods, are crucial for the development of effective conservation strategies. Roadside surveys (RS), especially those using vehicle-mounted video cameras, can be used to efficiently search for targets; however, they are limited by the unknown detection range. Distance sampling (DS), in which animal density or abundance is estimated from the distance between the observer and the detected individual, can provide a complimentary approach to address this limitation of RS. We developed a DS model robust to location uncertainty based on video-based RS. We integrated location errors determined by an independent field test using RS and unmanned aerial vehicles (UAVs) into a stochastic DS model. We estimated the abundance of herons and egrets in farmlands in and around the evacuation zone of the Fukushima Daiichi nuclear power plant accident by combining RS and DS. The video-based RS covered 7,031 km of roads and 24.41 km2 of farmlands. All herons and egrets were observed around the evacuation zone and none were detected in the zone. The predicted abundance of herons and egrets differed substantially between areas inside (0.0158 ± 0.0174/km2) and outside of the zone (4.62 ± 5.41/km2). Integrating location uncertainty into the DS model did not affect predicted heron and egret population densities (4.62 ± 5.41 vs. 4.66 ± 5.45/km2, with or without integrating location uncertainty, respectively). Accordingly, our survey method combining RS and DS is robust to location uncertainty. The study system (i.e., herons and egrets in farmlands) and the inability of location error to exceed the size of one farmland separated by levees may contribute to the accuracy of RS in this study. Synthesis and Applications: Combining RS with vehicle-mounted cameras and DS considering location uncertainty is widely applicable to open land species and can improve the efficiency of monitoring. When large location errors are expected by conventional approaches, DS models incorporating location uncertainty determined by RS and UAVs could be effective for abundance estimation over wide areas.

Nesting Distributions in Kansas of Selected Colonial Nesting Herons in 01/01/1982 and 01/01/1983

Abstract: During the nesting seasons of 1982 and 1983, a comprehensive, statewide survey was conducted to determine locations of nesting colonies of selected species of herons and the number of breeding birds present at each colony. Species include were the black-crowned night heron (Nycticorax nycticroax), yellow-crowned night heron (Nycticorax violaceus), little blue heron (Egretta thula) cattle egret (Bubulcus ibis), great egret (Casmerodius albus), and the white-faced ibis (Plegadis chihi). Eleven active nesting colonies were located and observed in eight counties in Kansas in 1982. In 1983, two additional colonies were located and three colonies active in 1982 were abandoned, yielding a total of ten active colonies in eight counties in the state at the present time.

Importance of appropriate reference intervals: A case of missed congenital hypothyroidism

Abstract: A 2-year-old girl was noted by her parents to have a lump at the back of her throat. It was readily visualised on protrusion of the tongue (Fig. 1). The possibility of a sublingual ectopic thyroid gland was raised and she was referred to the paediatric endocrine service. The girl had previously been examined by a paediatric endocrinologist at age 13 days following a positive newborn screen for congenital hypothyroidism. Whole blood thyroid-stimulating hormone (TSH) on newborn screening at 50 h of age was 13 mIU/L (positive screen cutoff ≥13; equivalent to serum TSH of 26 mIU/L). A repeat newborn screening card was requested and collected at age 7 days, the TSH was 8 mIU/L (age-adjusted positive screen cutoff ≥6 mIU/L). She was her parents’ first child, born 36 + 5 weeks gestation weighing 3045 g. There were no complications during pregnancy and no family history of thyroid disease. On a clinical review at age 13 days, she appeared normal, was gaining appropriate weight with no concerns raised. TSH was 8.2 mU/L serum (laboratory reference interval (RI) at our hospital laboratory 0.4–16) and fT4 20 pmol/L (10.0–40.0). These results were interpreted as normal, the family reassured and she was discharged from the endocrine service. She was reviewed again at age 2 years following discovery of the lump at the back of her throat. She had been growing well and developing normally with above-average language skills. She had no signs or symptoms of hypothyroidism and no issues with speech or swallowing. Her blood revealed compensated hypothyroidism with a TSH of 11.7 mU/L (0.50–4.50) and fT4 14.7 pmol/L (11.0–22.0). Imaging confirmed the presence of an ectopic sublingual thyroid gland. Thyroid scintiscan showed no uptake in the region of the thyroid, with focal increased uptake in the upper neck. Neck ultrasound scan found no thyroid tissue in the normal location with a 15-mm diameter thyroid tissue mass present in the sublingual position. She was started on 50 μg thyroxine (3.8 μg/ kg/day), with an aim to supress TSH to just below normal range in order to shrink the sublingual thyroid and make potential surgical resection easier. She has remained on the same dose over the last 12 months and has achieved TSH levels between 0.38 and 1.1 mU/L and slightly supra-physiological fT4 of 27–28 pmol/L without symptoms of hyperthyroidism. Her sublingual thyroid has become noticeably smaller (Fig. 2) since treatment was initiated.

O‎n ‎some ‎inequa‎lities ‎from ‎‎positive ‎‎matrices ‎to‎ ‎sector‎ matrices‎‎‎

Abstract: Abstract Note: Please see pdf for full abstract with equations. In the present paper, we discuss some inequalities related to sector matrices such as relative entropy, the Kantorovich inequality and Heron inequality. Among other results, we prove that if A ∈ M n be such that W(A) ⊆ S θ and 0 < m ≤ ℜA ≤ M . Then ℜΦ(A −1 ) ≤ K(h) sec 2 (θ)ℜΦ −1 (A) , where K(h) = (M+m) 2 /4Mm with h = M/m is the Kantorovich constant.

Population data of the Heron Colonies in the Reedbed of Lake Kolon from a Non- Disturbance high altitude Aerial Photogrammetry based Survey

Abstract: Abstract Indicator species can provide warning signals for upcoming changes or shifts to an ecosystem such as climate change. Heron colonies as indicators are also suitable for monitoring changes in our environment, the effectiveness of habitat restoration or the effects of impacts. That’s why the importance of population survey is increasing. We have tested a high-altitude survey method of a breeding heron colony in Lake Kolon pilot area that allows accurate bird counting without disturbing the birds. Previously, the survey of large body-sized heron colonies was only statistically well analysed for nest counts. Surveying breeding colonies using 0.5 cm field resolution orthophotos taken with calibrated cameras carried on aircraft flying at over 240 km/h from 700 m above the ground provides much more accurate information. Individuals can be detected on at least 14 orthophotos and additional oblique images, and the resolution and geometric accuracy of approximately 20 cm increases the reliability of identification and reduces the risk of multiple counts. The primary aim of the surveys is to provide data of the heron colonies in 2018 and 2019 in Lake Kolon, and to do so in a way that the examination does not cause disturbance to the birds.

Heron: A Knowledge Graph editor for intuitive implementation of python based experimental pipelines

Abstract: To realise a research project idea, an experimenter faces a series of conflicting design and implementation considerations, regarding both its hardware and software components. For instance, the ease of implementation, in time and expertise, should be balanced against the ease of future reconfigurability and number of ‘black box’ components. Other, often conflicting, considerations include the level of documentation and ease of reproducibility, resource availability as well as access to online communities. To alleviate this balancing act between opposing requirements we present Heron, a new Python-based platform to construct and run experimental and data analysis pipelines. Heron’s main principle is to allow researchers to design and implement the experimental flow as close as possible to their mental schemata of the experiment, in the form of a Knowledge Graph. Heron is designed to increase the implementation speed of experiments (and their subsequent updates), while minimising the number of incorporated black box components. It enhances the readability and reproducibility of the final implementation and allows the use of combinations of hardware and software otherwise impossible or too costly to achieve. Given this, Heron offers itself to sciences whose needs involve experiments with a large number of interconnected hardware and software components like robotics, neuroscience, behavioural sciences, physics, chemistry, environmental science, etc.. It is designed with those experimentalists in mind which: i) Demand full control of their setup. ii) Prefer not to have to choose between hardware and software that run only on a specific chip/operating system combination. iii) Appreciate the ease and speed that high-level languages (e.g. Python) and Graphical User Interfaces (GUIs) offer them. It assumes an intermediate knowledge of the Python language and ecosystem, offering a flexible and powerful way to construct experimental setups. It removes any inaccessible corners, yet keeps implementation costs significantly reduced compared to using lower level languages. Finally, its use results in a much cleaner and easier to understand code base, amicable to documentation and reproducibility efforts.

Spherical Heron triangles and elliptic curves

Abstract: We define spherical Heron triangles (spherical triangles with “rational” side-lengths and angles) and parametrize them via rational points of certain families of elliptic curves. We show that the congruent number problem has infinitely many solutions for most areas in the spherical setting and we find a spherical Heron triangle with rational medians. We also explore the question of spherical triangles with a single rational median or a single a rational area bisector (median splitting the triangle in half), and discuss various problems involving isosceles spherical triangles.

Successful nest defence of Eurasian reed warblers Acrocephalus scirpaceus against the little bittern Ixobrychus minutus

Abstract: Abstract The cost–benefit approach to nest defence behaviour is based on an assumption that parents are able to distract potential predators away from their nest. However, this assumption has received little support from direct observations as predator-prey encounters near nests are rarely recorded, especially in small passerines. Here, we describe two observations of little bitterns appearing near nests of Eurasian reed warblers containing nestlings and eggs, respectively. In both cases parental birds showed anti-predatory behaviour, which was much more vigorous at the nestling stage than at the egg stage. During both observations, the heron finally flew away and did not attack the nest content, indicating that nest defence behaviour of small passerines may be effective.

Faster and Better: Comparison between Traditional and Drone Monitoring in a Cryptic Species, the Purple Heron Ardea purpurea

Abstract: Monitoring waterbirds is fundamental to understand the health status of wetland habitats. However, this monitoring has to be conducted by means of reliable data collection that can provide accurate information on population trends. Usually, waterbird monitoring is difficult, as nesting grounds are usually located in inaccessible reedbed, and by eye detection of cryptic species is hard. Drones have the capacity to overcome most of these problems, as they can provide with an aerial view of places otherwise unreachable, while reducing the disturbance and time spent in the field. The present study aims to compare the accuracy, disturbance levels, and managerial efficiency between ground (traditional) and drone counts of a cryptic species, the Purple Heron Ardea purpurea. Traditional monitoring methods were only capable of detecting 35% of the nesting pairs detected by the drone surveys (8.0 ± 11.8 versus 22.9 ± 38.2 nesting pairs in ground and drone surveys, respectively). Consequently, colony size estimates between methods showed poor agreement, to the point that traditional methods missed colonies otherwise detected by the drone. No apparent negative effects on nesting pairs where found when flying the drone. In addition, mean time spent to survey breeding sites with a drone was far less than with the traditional approach, down to a six-fold time reduction. This reduction, together with a lack of disturbance observed when conducting the drone monitoring, and an increasing monitoring precision and accuracy, supports the use of drones as the least invasive option for studies on population monitoring on hardly accessible sites.

Heron’s Legacy: An Example of Ancient Calculations Applied to Roman Imperial Architecture

Abstract: Abstract Heron of Alexandria is a well-known author in the field of mathematics and engineering, but his work is of great interest for understanding ancient construction problems related to architecture. The formulas translated and commented on by Heiberg (1914a, b) are analyzed through geometric diagrams and applied to famous Roman domed architecture.

Line-Bound Vectors, Plane-Bound Bivectors, and Heron's Formula for Tetrahedra

Abstract: Abstract The representation of some elementary geometric concepts in the conformal geometric algebra of three dimensions are reviewed, and their connections to a recently discovered extension of Heron's formula for the area of a triangle to the volume of a tetrahedron are discussed. Mathematics Subject Classification (2010) . Primary 51M04; Secondary 11E88, 15A67, 51M25, 51M30, 52A38, 52B10.

Green turtle (Chelonia mydas) hatching success at Raine and Heron Islands

Abstract: Raine Island, the world’s largest green turtle nesting location, has low nest hatching success. The main causes of this low hatching success are thought to be nest destruction by subsequent nesting females, and inundation of nests during high tides and storm surges. But even nests that are protected from nest destruction and inundation appear to have relatively low hatching success, with most of the embryo mortality occurring early in incubation. Here, I compare hatching success and developmental phase of embryo death of protected ‘dry’ nests from Raine Island (RI) with similar nests from Heron Island (HI), a nesting location previously reported as having high hatching success. Nests at both sites were sampled close to the peak time of nesting (December). Twenty-eight nests were sampled at RI and 14 nests at HI. Nest temperatures were cooler during the first week of incubation at HI (median 26.9°C) than at RI (median 30.1°C), but three-days-in-a-row maximum nest temperatures were higher at HI (median 36.0°C) than at RI (median 33.5°C). I found the hatching success of sampled nests at both locations was similar, ~70%, but most embryo death occurred early in incubation at RI (median 16.5%) compared to HI (median 3.8%), but late in incubation at HI (median 4.9%) compared to RI (median 0.2%).

Genetic Characterization and Pathogenesis of Avian Influenza Virus H3N8 Isolated from Chinese pond heron in China in 2021

Abstract: In October 2021, a wild bird-origin H3N8 influenza virus-A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8)-was isolated from Chinese pond heron in China. Phylogenetic and molecular analyses were performed to characterize the genetic origin of the H3N8 strain. Phylogenetic analysis revealed that eight gene segments of this avian influenza virus H3N8 belong to Eurasian lineages. HA gene clustered with avian influenza viruses is circulating in poultry in southern China. The NA gene possibly originated from wild ducks in South Korea and has the highest homology (99.3%) with A/Wild duck/South Korea/KNU2020-104/2020 (H3N8), while other internal genes have a complex and wide range of origins. The HA cleavage site is PEKQTR↓GLF with one basic amino acid, Q226 and T228 at HA preferentially bind to the alpha-2,3-linked sialic acid receptor, non-deletion of the stalk region in the NA gene and no mutations at E627K and D701N of the PB2 protein, indicating that isolate A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) was a typical avian influenza with low pathogenicity. However, there are some mutations that may increase pathogenicity and transmission in mammals, such as N30D, T215A of M1 protein, and P42S of NS1 protein. In animal studies, A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) replicates inefficiently in the mouse lung and does not adapt well to the mammalian host. Overall, A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) is a novel wild bird-origin H3N8 influenza virus reassortant from influenza viruses of poultry and wild birds. This wild bird-origin avian influenza virus is associated with wild birds along the East Asian-Australasian flyway. Therefore, surveillance of avian influenza viruses in wild birds should be strengthened to assess their mutation and pandemic risk in advance.

Heronian elliptic curves and the size of the $2$-Selmer group

Abstract: A generalization of the congruent number problem is to find positive integers $n$ that appear as the areas of Heron triangles. Selmer group of a congruent number elliptic curve has been studied quite extensively. Here, we look into the $2$-Selmer group structure for Heronian elliptic curves associated with Heron triangles of area $n$ and one of the angle $\theta$ such that $\tan \frac{\theta}{2} = n^{-1}$ and $n^{2}+1=2q$ for some prime $q$.