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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dawei Liu ◽  
Yongwu Zhou ◽  
Yiling Fei ◽  
Chunping Xie ◽  
Senlin Hou

AbstractHistorically, the diving duck, Baer’s Pochard (Aythya baeri) was widely distributed in East and South Asia, but according to a recent estimate, its global population is now less than 1000 individuals. To date, the mitochondrial genome of A. baeri has not been deposited and is not available in GenBank. Therefore, we aimed to sequence the complete mitochondrial genome of this species. The genome was 16,623 bp in length, double stranded, circular in shape, and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one non-coding control region. Many structural and compositional similarities were discovered between A. baeri and the other three Aythya mitochondrial genomes. Among 13 protein-coding genes of the four Aythya species, the fastest-evolving gene was ATP8 while the slowest-evolving gene was COII. Furthermore, the phylogenetic tree of Anatidae based on Bayesian inference and maximum likelihood methods showed that the relationships among 15 genera of the Anatidae family were as follows: Dendrocygna was an early diverging lineage that was fairly distant from the other ingroup taxa; Cygnus, Branta, and Anser were clustered into one branch that corresponded to the Anserinae subfamily; and Aythya, Asarcornis, Netta, Anas, Mareca, Mergus, Lophodytes, Bucephala, Tadorna, Cairina, and Aix were clustered into another branch that corresponded to the Anatinae subfamily. Our target species and three other Aythya species formed a monophyletic group. These results provide new mitogenomic information to support further phylogenetic and taxonomic studies and genetic conservation of Anatidae species.


2021 ◽  
Author(s):  
◽  
Jacqueline Valerie Phoebe Le Roux

<p>Leiopelma pakeka is an archaic frog native to New Zealand, and until recently was restricted to a 15ha forest remnant on the south-east face of Maud Island. The L.pakeka population appears to be growing and spreading out from the forest remnant. This study investigated the population size, structure, and distribution of L. pakeka on Maud Island in 2006. The forest remnant was searched using 106 randomly placed 25m2 plots. Population size was estimated using a bootstrap method repeated 10,000 times, adjusted for likelihood of emergence, likely maximum plot population size, and area. The average population size was 34,449 frogs, which is much higher than a 1994 minimum number alive estimate of 19,312. The new figure, however, is similar to another recent estimate of 39,563, based on an update of the 1994 figure. Distributional patterns within the forest remnant were similar to the 1994 study, with most frogs between 90-170m above sea level. The comparability of the population size estimates indicates that L. pakeka numbers have reached the carrying capacity of the forest remnant. The distribution of the remnant L. pakeka population was determined by thoroughly searching the south-east face of Maud Island, thereby minimising the possibility of missing frogs. A total of 232 frogs were found. Frogs generally colonised areas within 50m of the remnant; movement was greater in regenerating forest (75m in the southwest and 100m in the north east) than in pastoral areas (<25m). The size of frogs increased with distance from the forest remnant (weight, girth, condition index, and average snout-vent and tibio-fibula lengths). The size increases may be indications of competitive release, as frog density decreased with distance from the forest remnant. The size range of Leiopelma pakeka was extended by the current study from 50.5mm to at least 52mm snout-vent length. A total of 15 L. pakeka were found on Fort Road, approximately 350m from the remnant. These frogs were most likely in the area before 1994. The Fort Road frogs were compared to the forest remnant L. pakeka, and were not morphologically distinct as only patterning differed significantly. Fort Road L. pakeka may belong to a separate subpopulation. L. pakeka distribution was significantly affected by habitat. Important variables were vegetation type, and rock, canopy, sub-canopy, and leaf litter cover. The size of emergent frogs (tibio-fibula length) was significantly and positively correlated with relative humidity.</p>


2021 ◽  
Author(s):  
◽  
Jacqueline Valerie Phoebe Le Roux

<p>Leiopelma pakeka is an archaic frog native to New Zealand, and until recently was restricted to a 15ha forest remnant on the south-east face of Maud Island. The L.pakeka population appears to be growing and spreading out from the forest remnant. This study investigated the population size, structure, and distribution of L. pakeka on Maud Island in 2006. The forest remnant was searched using 106 randomly placed 25m2 plots. Population size was estimated using a bootstrap method repeated 10,000 times, adjusted for likelihood of emergence, likely maximum plot population size, and area. The average population size was 34,449 frogs, which is much higher than a 1994 minimum number alive estimate of 19,312. The new figure, however, is similar to another recent estimate of 39,563, based on an update of the 1994 figure. Distributional patterns within the forest remnant were similar to the 1994 study, with most frogs between 90-170m above sea level. The comparability of the population size estimates indicates that L. pakeka numbers have reached the carrying capacity of the forest remnant. The distribution of the remnant L. pakeka population was determined by thoroughly searching the south-east face of Maud Island, thereby minimising the possibility of missing frogs. A total of 232 frogs were found. Frogs generally colonised areas within 50m of the remnant; movement was greater in regenerating forest (75m in the southwest and 100m in the north east) than in pastoral areas (<25m). The size of frogs increased with distance from the forest remnant (weight, girth, condition index, and average snout-vent and tibio-fibula lengths). The size increases may be indications of competitive release, as frog density decreased with distance from the forest remnant. The size range of Leiopelma pakeka was extended by the current study from 50.5mm to at least 52mm snout-vent length. A total of 15 L. pakeka were found on Fort Road, approximately 350m from the remnant. These frogs were most likely in the area before 1994. The Fort Road frogs were compared to the forest remnant L. pakeka, and were not morphologically distinct as only patterning differed significantly. Fort Road L. pakeka may belong to a separate subpopulation. L. pakeka distribution was significantly affected by habitat. Important variables were vegetation type, and rock, canopy, sub-canopy, and leaf litter cover. The size of emergent frogs (tibio-fibula length) was significantly and positively correlated with relative humidity.</p>


2021 ◽  
Author(s):  
Matthew Baum ◽  
Ata Uslu ◽  
Anjuli Shere ◽  
David Lazer ◽  
Kristin Lunz Trujillo ◽  
...  

COVID-19 continues to surge in the United States and elsewhere, propelled by the highly contagious Delta variant. As of this writing (on September 29, 2021), about three quarters (76%) of the eligible U.S. population (age 12 and up) have received at least one dose of a COVID-19 vaccine. This is likely not enough to achieve herd immunity in the United States. Though the specific number remains uncertain, a recent estimate by the Infectious Diseases Society of America suggests that over 80% of the entire population must be fully vaccinated to reach herd immunity.More worrisome, around 1 in 5 Americans, depending on the poll, continue to say they are either uncertain or will not get the vaccine. In our most recent survey wave (fielded from August 26 to September 27, 2021), 10% of respondents who indicated that they are not yet vaccinated claimed they are extremely unlikely to get it. Another 12% are “somewhat” unlikely to seek the vaccine.In recent weeks, the Biden administration has shifted tactics in its efforts to get as many Americans as possible vaccinated. The Administration had from the outset emphasized the benefits of getting vaccinated as its primary strategy for persuading reluctant Americans to do so. Yet, starting in September the prevailing strategy seemingly shifted from emphasizing carrots to sticks. On September 9th, President Biden issued an executive order requiring all federal employees and government contractors to be vaccinated, and also announced that the U.S. Department of Labor would require that all companies with more than 100 employees require vaccination or weekly testing, as well as provide paid time off for employees to get vaccinated. The Biden Administration has also encouraged states and smaller companies to impose similar vaccine mandates.The question arises as to whether the persistence of the Delta variant has increased public support for making COVID-19 vaccines mandatory. In our April/May survey wave, six in ten respondents approved of the government mandating vaccines for everyone (see Report #52). This figure increased modestly, to 64% in our June/July survey (see Report #58).In this report, we update our assessment of public support for vaccine mandates, both nationally and across the 50 states, based on our September survey wave.


2021 ◽  
Vol 13 (9) ◽  
pp. 4263-4274
Author(s):  
Yuanyuan Huang ◽  
Phillipe Ciais ◽  
Maurizio Santoro ◽  
David Makowski ◽  
Jerome Chave ◽  
...  

Abstract. As a key component of the Earth system, roots play a key role in linking Earth's lithosphere, hydrosphere, biosphere and atmosphere. Here we combine 10 307 field measurements of forest root biomass worldwide with global observations of forest structure, climatic conditions, topography, land management and soil characteristics to derive a spatially explicit global high-resolution (∼ 1 km) root biomass dataset, including fine and coarse roots. In total, 142 ± 25 (95 % CI) Pg of live dry-matter biomass is stored belowground, representing a global average root : shoot biomass ratio of 0.25 ± 0.10. Earlier studies (Jackson et al., 1997; Robinson, 2007; Saugier et al., 2001) are 44 %–226 % larger than our estimations of the total root biomass in tropical, temperate and boreal forests. The total global forest root biomass from a recent estimate (Spawn et al., 2020) is 24 % larger than this study. The smaller estimation from this study is attributable to the updated forest area, spatially explicit aboveground biomass density used to predict the patterns of root biomass, new root measurements and the upscaling methodology. We show specifically that the root shoot allometry is one underlying driver that has led to methodological overestimation of root biomass in previous estimations. Raw datasets and global maps generated in this study are deposited at the open-access repository Figshare (https://doi.org/10.6084/m9.figshare.12199637.v1; Huang et al., 2020).


Author(s):  
Olivier Bordellès

We first study the mean value of certain restricted divisor sums involving the Chowla–Walum sums, improving in particular a recent estimate given by Iannucci. The aim of the second part of this work is the generalization of the previous study, by restricting the range of the divisors in the studied divisor sums, extending the Chowla–Walum conjecture, proving a small part of this extended conjecture and generalizing the asymptotic formulas previously obtained in the first part.


Phytotaxa ◽  
2021 ◽  
Vol 500 (1) ◽  
pp. 52-54
Author(s):  
RAMALINGAM KOTTAIMUTHU ◽  
PERUMAL MURUGAN ◽  
JOHN KENNEDY JOHN PRAVEEN KUMAR ◽  
MUTHURAMALINGAM JOTHI BASU

The genus Impatiens Linnaeus (1753: 937) contains a wealth of untapped treasures for gardeners and it is one of the mega diverse genera of angiosperms comprise about 1059 species (POWO 2020). According to the recent estimate, India is known to have 250 species and majority of them occur in Eastern Himalayas (Gogoi et al. 2018) and the Western Ghats (Bhaskar 2012). Tamil Nadu is one of the plant-rich states in the country and with 5674 angiosperm taxa, it ranks first among all the states in the country (Lakshminarasimhan et al. 2014).


Phytotaxa ◽  
2020 ◽  
Vol 477 (1) ◽  
pp. 97-98
Author(s):  
RAMALINGAM KOTTAIMUTHU ◽  
MUTHURAMALINGAM JOTHI BASU ◽  
KULLAIYAN SATHIYADASH ◽  
VELUSWAMY KARTHIKEYAN

Cissus Linnaeus (1753: 117) is the most speciose genus in the family Vitaceae and notable for its pantropical intercontinental disjunct pattern (Liu et al. 2013). According to the recent estimate, the genus is known to have 291 accepted species (POWO 2020) and it is widely distributed in tropical regions of Africa, Asia, Australia, Central and South America and Mexico (Wen 2007). The main characters delimiting Cissus from other Vitaceae genera are the well-developed, thick and undivided floral disks, tetramerous flowers, one-seeded berries, and seeds with a long and linear chalaza (Wen 2007). In South America, Cissus is represented by 64 species (Lombardi 2000, 2007, Rodrigues et al. 2014). Amongst C. ulmifolia (Baker 1871: 213) Planchon (1887: 552) that is a later homonym of an Italian fossil taxon Cissus ulmifolia Massalongo (1858: 80). While checking the literature and relevant websites for the availability of any synonyms, we found that C. allenii Croat (1977: 358) and C. serrulatifolia Williams (1962: 375) are listed as heterotypic synonyms of C. ulmifolia in Tropicos (2020) following Nelson (2010). However, C. allenii was synonymized under C. serrulatifolia by most of the workers (Govaerts 1999, Lombardi 2007, Morales 2015, POWO 2020, Raz & Zamora 2020) but C. ulmifolia was treated as a distinct species. So in order to ascertain the taxonomic status, we critically studied the protologues and digital specimens including types of these three species, we found that the characters of C. allenii are well within the range of C. serrulatifolia but C. ulmifolia differs from them by its 4-sided, distinctly winged stem (vs. stem terete, not winged or wingless in C. serrulatifolia) and the fruits ovoid or ovoid–subglobose, smooth (vs. obovoid or subpyriform, lenticellate in C. serrulatifolia). Since no other validly published legitimate name is available for this species (Lombardi 2007, Mota de Oliveira & Jansen-Jacobs 2016, POWO 2020), therefore, the authors propose Cissus lombardiana as a replacement name.


Author(s):  
J Delhaize ◽  
I Heywood ◽  
M Prescott ◽  
M J Jarvis ◽  
I Delvecchio ◽  
...  

Abstract We report the discovery of two new giant radio galaxies (GRGs) using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. Both GRGs were found within a ∼1 deg2 region inside the COSMOS field. They have redshifts of z = 0.1656 and z = 0.3363 and physical sizes of 2.4 Mpc and 2.0 Mpc, respectively. Only the cores of these GRGs were clearly visible in previous high resolution VLA observations, since the diffuse emission of the lobes was resolved out. However, the excellent sensitivity and uv coverage of the new MeerKAT telescope allowed this diffuse emission to be detected. The GRGs occupy an unpopulated region of radio power – size parameter space. Based on a recent estimate of the GRG number density, the probability of finding two or more GRGs with such large sizes at z &lt; 0.4 in a ∼1 deg2 field is only 2.7 × 10−6, assuming Poisson statistics. This supports the hypothesis that the prevalence of GRGs has been significantly underestimated in the past due to limited sensitivity to low surface brightness emission. The two GRGs presented here may be the first of a new population to be revealed through surveys like MIGHTEE which provide exquisite sensitivity to diffuse, extended emission.


2020 ◽  
Vol 644 ◽  
pp. A13
Author(s):  
T. Stolker ◽  
G.-D. Marleau ◽  
G. Cugno ◽  
P. Mollière ◽  
S. P. Quanz ◽  
...  

The circumstellar disk of PDS 70 hosts two forming planets, which are actively accreting gas from their environment. The physical and chemical characteristics of these planets remain ambiguous due to their unusual spectral appearance compared to more evolved objects. In this work, we report the first detection of PDS 70 b in the Brα and M′ filters with VLT/NACO, a tentative detection of PDS 70 c in Brα, and a reanalysis of archival NACO L′ and SPHERE H23 and K12 imaging data. The near side of the disk is also resolved with the Brα and M′ filters, indicating that scattered light is non-negligible at these wavelengths. The spectral energy distribution (SED) of PDS 70 b is well described by blackbody emission, for which we constrain the photospheric temperature and photospheric radius to Teff = 1193 ± 20 K and R = 3.0 ± 0.2 RJ. The relatively low bolometric luminosity, log(L∕L⊙) = −3.79 ± 0.02, in combination with the large radius, is not compatible with standard structure models of fully convective objects. With predictions from such models, and adopting a recent estimate of the accretion rate, we derive a planetary mass and radius in the range of Mp ≈ 0.5–1.5 MJ and Rp ≈ 1–2.5 RJ, independently of the age and post-formation entropy of the planet. The blackbody emission, large photospheric radius, and the discrepancy between the photospheric and planetary radius suggests that infrared observations probe an extended, dusty environment around the planet, which obscures the view on its molecular composition. Therefore, the SED is expected to trace the reprocessed radiation from the interior of the planet and/or partially from the accretion shock. The photospheric radius lies deep within the Hill sphere of the planet, which implies that PDS 70 b not only accretes gas but is also continuously replenished by dust. Finally, we derive a rough upper limit on the temperature and radius of potential excess emission from a circumplanetary disk, Teff ≲ 256 K and R ≲ 245 RJ, but we do find weak evidence that the current data favors a model with a single blackbody component.


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