scholarly journals Atypus karschi Dönitz, 1887 (Araneae: Atypidae): an Asian purse-web spider established in Pennsylvania, USA

2021 ◽  
Author(s):  
Milan Řezáč ◽  
Steven Tessler ◽  
Petr Heneberg ◽  
Ivalú Macarena Ávila Herrera ◽  
Nela Gloríková ◽  
...  
Keyword(s):  
Sex Chromosome ◽  
Carabid Beetles ◽  
Eastern Coast ◽  
Physical Parameters ◽  
Web Spider ◽  
Wide Range ◽  
Close Relationship ◽  
Eastern Usa ◽  
The Usa ◽  
Sex Chromosome System

The Mygalomorph spiders of the family Atypidae are among the most archaic spiders. The genus Atypus Latreille, 1804 occurs in Eurasia and northern Africa, with a single enigmatic species, Atypus snetsingeri Sarno, 1973, restricted to a small area in southeastern Pennsylvania in Eastern USA. This study was undertaken to learn more about genetics of that species, its habitat requirements and natural history. A close relationship to European species could be assumed based on A. snetsingeri’s occurrence on the eastern coast of the USA, however molecular markers (CO1 sequences) confirmed that A. snetsingeri is identical with Atypus karschi Dönitz, 1887 native to East Asia; it is an introduced species. The specific epithet snetsingeri is therefore relegated to a junior synonym of A. karschi . The karyotype of A. karschi has 42 chromosomes in females and 41 in males (X0 sex chromosome system). Chromosomes were metacentric except for one pair, which exhibited submetacentric morphology. In Pennsylvania the above-ground webs are usually vertical and attached to the base of bushes, trees, or walls, although some webs are oriented horizontally near the ground. It was found in a variety of habitats from forests to suburban shrubbery, and over a wide range of soil humidity and physical parameters. Prey include millipedes, snails, woodlice, carabid beetles and earthworms. The number of juveniles in excavated female webs ranged from 70 to 201. Atypus karschi is the first known case of an introduced purse-web spider. It is rarely noticed but well-established within its range in southeastern Pennsylvania.

scholarly journals White clover ecotype germplasm from the USA for development of New Zealand and overseas cultivars

1996 ◽  
Vol 6 ◽  
pp. 149-153
Author(s):  
K.H. Widdup ◽  
J.R. Caradus ◽  
J. Green ◽  
Mueller Pennell
Keyword(s):  
North Carolina ◽  
New Zealand ◽  
White Clover ◽  
Leaf Size ◽  
The North ◽  
Nodal Roots ◽  
Wide Range ◽  
Eastern Usa ◽  
The Usa ◽  
Small Set

An ecotype collection of 98 populations of white clover (Trifolium repens L.) from pastures in the eastern USA together with five USA Ladino and five New Zealand cultivars were grown in grass swards at Raleigh, North Carolina; Palmerston North and Lincoln, New Zealand. The material was compared for leaf size, cyanogenesis, seasonal growth, % clover cover and persistence. When examined as a single group, the USA ecotypes consisted of a wide range of plant types from small-leaved acyanogenic to large-leaved cyanogenic types. This contrasted with the uniformly large-leaved acyanogenic USA Ladino cultivars which have been the principal cultivars sown in eastern USA. Various selection pressures over time together with introgression between Ladino and resident wild clover types has resulted in a wide array of plant types. At the North Carolina site, USA ecotype material generally demonstrated better growth and persistence compared to the USA Ladino and New Zealand cultivars. The best ecotype plots from the Piedmont (inland region) had 55% clover cover by the third spring compared to 12% cover from the USA cultivar, SRVR and 2% cover from the NZ cultivar, Huia. Selective pressures such as hot summers, viruses, root-feeding pests and other stresses on the local clover types have resulted in ecotype material with improved adaptive features. The USA ecotype collection is an important source of germplasm for development of improved white clovers for the eastern USA. At the New Zealand sites, the USA material demonstrated pooraverage yields compared to NZ cultivars. However, a small set of USA ecotypes showed good recovery following the dry 1995 summer at Lincoln and this material warrants closer examination to determine the adaptive mechanisms involved. As the USA ecotypes show a general lack of adaptation to New Zealand pastures, any desirable features such as heat tolerance, deeper nodal roots or virus resistance uncovered in this material will require hybridisation and backcrossing with selected elite New Zealand material to capture the benefits. Keywords: adaptation, eastern USA, ecotype populations,

Elaeagnus angustifolia (Russian olive).

2021 ◽  
Author(s):  
Philip Weyl ◽  
Nick Pasiecznik
Keyword(s):  
Root System ◽  
Paper Mill ◽  
Annual Rainfall ◽  
Moist Sand ◽  
Western Asia ◽  
Wide Range ◽  
Bee Foraging ◽  
Eastern Usa ◽  
The Usa ◽  
Tall Shrub

Abstract E. angustifolia is a tall shrub (up to 15 m and 1 m d.b.h.), with a dense, rounded crown, native to Europe and Asia and an important deciduous species of arid and semi-arid areas of northwestern China. It was introduced into the USA in the early 1900s, and has now become extensively naturalized in riparian areas of western states bordered on the east by North and South Dakota, Nebraska, Kansas, Oklahoma and Texas (Olson and Knopf, 1986a, 1986b; Shafroth et al., 1995). It also occurs in southern Canada from Ontario to British Columbia. It grows in some eastern USA states, but is not naturalized (Tesky, 1992). This fast-growing (up to 1.8 m per year), nitrogen-fixing species has silver-grey leaves with entire margins (4.5-9 cm), olive-shaped fruit and long thorns. The branches are flexible, pubescent (grey and scaly) and often have a short thorn at the end. The bark is brown, thin with shallow fissures, peeling in long strips. It has a deep taproot and well-developed lateral root system. The small, yellow flowers occur in late spring and have a distinctive spicy aroma. Trees produce seed after 3-5 years, with birds and small mammals dispersing them in their droppings. The seeds can remain viable for up to 3 years and are capable of germinating over a broad range of soil types (Knopf and Olson, 1984). Germination is enhanced by stratification in moist sand for 90 days at 41°C (Vines, 1960). E. angustifolia is found in a range of environments as it is tolerant of drought and saline, alkaline or infertile soils (Vines, 1960; Olson and Knopf, 1986a, 1986b), and has a well-developed root system. It is commonly found growing along floodplains, river banks, stream courses, marshes and irrigation ditches in the western states of the USA, and in desert or dry (150 mm annual rainfall) areas of Western Asia. It bears few fruits if the annual precipitation is >400 mm and also grows slowly if the water table is below 4 m. E. angustifolia is mainly established from seed, although cuttings are used in areas with sufficient moisture. It is relatively shade-tolerant once established and can withstand competition from other shrubs and trees, and can become a dominant climax species, replacing native cottonwoods and willows along water courses in the USA. E. angustifolia has been widely planted in shelterbelts, windbreaks or protective plantings as it is hardy, adaptable to a wide range of soil and moisture conditions and has a dense growth form (Brothers, 1988). It has also been used to revegetate land contaminated by paper mill wastewater (Wagner et al., 1994), potassium (Heinze and Liebmann, 1998) and bentonite (Uresk and Yamamoto, 1994), mine spoilings and as a bioindicator of heavy metal pollution (Aksoy and Sahin, 1999). The timber is hard and brownish-yellow with a beautiful grain, being similar to that of white elm (Ulmus pumila, U. americana). It can be used to make farm tools, furniture and for mining poles and civil construction. The fruits and leaves are valuable for food and animal fodder, whilst the tree is considered a good source for bee foraging. The leaves, shoots, flowers, fruits and bark have been traditionally used in Chinese medicine.

The Golden Age of Microanalysis.

1999 ◽  
Vol 5 (S2) ◽  
pp. 546-547
Author(s):  
Kurt F. J. Heinrich
Keyword(s):  
Summer School ◽  
Naval Research ◽  
Physical Parameters ◽  
New Device ◽  
Complex Interactions ◽  
Instrument Construction ◽  
Wide Range ◽  
Personal Connections ◽  
The Usa ◽  
Initial Source

The main initial source of information in the USA concerning the electron probe was a meeting at the Naval Research Laboratories in February 1958, followed in 1960 by a summer school at MIT organized by Prof. Norton and R. Ogilvie. Further visits to the USA and publications in English by the inventor of the instrument, R. Castaing, also contributed to the attention given here to the new technique. Since numerous research laboratories in the USA were keenly interested in the new device, the development of instruments and the contributions to its use were considerable. The relatively small number of active researchers in the field rendered personal connections and cooperation possible and attractive.Before the availability of American-made commercial microprobes, many investigators built their own instruments. Most of them were not trained as instrument builders, and the usefulness of the resulting devices was somewhat limited. These improvisations in instrument construction ceased once commercial microprobe manufacturers entered the field. Yet, in the process, much was learned and the American investigators contributed significantly to the theory of microanalysis. We realized that, with the limited calculation facilities then available, the complex interactions leading to the x-ray signal had to be treated in simplified ways, and we described ‘approximations’ rather than ‘laws’ in our efforts to understand and quantitatively describe the physical facts. We also came to realize that even where the physical processes were well known, we often lacked the knowledge of the physical parameters required for quantitation and the effect of their uncertainties on the accuracy of the analytical results. Another area in which advances were needed, and soon achieved, was the application of the technique to a wide range of technical and scientific problems. The interaction between manufacturers and users greatly stimulated improvements in the instrument design.

scholarly journals Geospatial Analysis of COVID-19: A Scoping Review

2021 ◽  
Vol 18 (5) ◽  
pp. 2336
Author(s):  
Munazza Fatima ◽  
Kara J. O’Keefe ◽  
Wenjia Wei ◽  
Sana Arshad ◽  
Oliver Gruebner
Keyword(s):  
Disease Mapping ◽  
Geospatial Analysis ◽  
Hotspot Analysis ◽  
Spatial Studies ◽  
Epidemiological Modeling ◽  
Wide Range ◽  
Scoping Reviews ◽  
Disease Pattern ◽  
The Usa ◽  
Meta Analyses

The outbreak of SARS-CoV-2 in Wuhan, China in late December 2019 became the harbinger of the COVID-19 pandemic. During the pandemic, geospatial techniques, such as modeling and mapping, have helped in disease pattern detection. Here we provide a synthesis of the techniques and associated findings in relation to COVID-19 and its geographic, environmental, and socio-demographic characteristics, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) methodology for scoping reviews. We searched PubMed for relevant articles and discussed the results separately for three categories: disease mapping, exposure mapping, and spatial epidemiological modeling. The majority of studies were ecological in nature and primarily carried out in China, Brazil, and the USA. The most common spatial methods used were clustering, hotspot analysis, space-time scan statistic, and regression modeling. Researchers used a wide range of spatial and statistical software to apply spatial analysis for the purpose of disease mapping, exposure mapping, and epidemiological modeling. Factors limiting the use of these spatial techniques were the unavailability and bias of COVID-19 data—along with scarcity of fine-scaled demographic, environmental, and socio-economic data—which restrained most of the researchers from exploring causal relationships of potential influencing factors of COVID-19. Our review identified geospatial analysis in COVID-19 research and highlighted current trends and research gaps. Since most of the studies found centered on Asia and the Americas, there is a need for more comparable spatial studies using geographically fine-scaled data in other areas of the world.

scholarly journals Evolution of a Multiple Sex-Chromosome System by Three-Sequential Translocations among Potential Sex-Chromosomes in the Taiwanese Frog Odorrana swinhoana

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 661
Author(s):  
Ikuo Miura ◽  
Foyez Shams ◽  
Si-Min Lin ◽  
Marcelo de Bello Cioffi ◽  
Thomas Liehr ◽  
...  
Keyword(s):  
Sex Chromosomes ◽  
Rare Case ◽  
Sex Chromosome ◽  
Sex Chromosome System ◽  
Brown Frog ◽  
Male Specific

Translocation between sex-chromosomes and autosomes generates multiple sex-chromosome systems. It happens unexpectedly, and therefore, the evolutionary meaning is not clear. The current study shows a multiple sex chromosome system comprising three different chromosome pairs in a Taiwanese brown frog (Odorrana swinhoana). The male-specific three translocations created a system of six sex-chromosomes, ♂X1Y1X2Y2X3Y3 -♀X1X1X2X2X3X3. It is unique in that the translocations occurred among three out of the six members of potential sex-determining chromosomes, which are known to be involved in sex-chromosome turnover in frogs, and the two out of three include orthologs of the sex-determining genes in mammals, birds and fishes. This rare case suggests sex-specific, nonrandom translocations and thus provides a new viewpoint for the evolutionary meaning of the multiple sex chromosome system.

scholarly journals A Computational Study on the Role of Parameters for Identification of Thyroid Nodules by Infrared Images (and Comparison with Real Data)

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4459
Author(s):  
José R. González ◽  
Charbel Damião ◽  
Maira Moran ◽  
Cristina A. Pantaleão ◽  
Rubens A. Cruz ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thyroid Nodules ◽  
Numerical Study ◽  
Computational Study ◽  
Internal Heat ◽  
Heat Transfer Process ◽  
The Body ◽  
Physical Parameters ◽  
Infrared Sensors ◽  
Wide Range

According to experts and medical literature, healthy thyroids and thyroids containing benign nodules tend to be less inflamed and less active than those with malignant nodules. It seems to be a consensus that malignant nodules have more blood veins and more blood circulation. This may be related to the maintenance of the nodule’s heat at a higher level compared with neighboring tissues. If the internal heat modifies the skin radiation, then it could be detected by infrared sensors. The goal of this work is the investigation of the factors that allow this detection, and the possible relation with any pattern referent to nodule malignancy. We aim to consider a wide range of factors, so a great number of numerical simulations of the heat transfer in the region under analysis, based on the Finite Element method, are performed to study the influence of each nodule and patient characteristics on the infrared sensor acquisition. To do so, the protocol for infrared thyroid examination used in our university’s hospital is simulated in the numerical study. This protocol presents two phases. In the first one, the body under observation is in steady state. In the second one, it is submitted to thermal stress (transient state). Both are simulated in order to verify if it is possible (by infrared sensors) to identify different behavior referent to malignant nodules. Moreover, when the simulation indicates possible important aspects, patients with and without similar characteristics are examined to confirm such influences. The results show that the tissues between skin and thyroid, as well as the nodule size, have an influence on superficial temperatures. Other thermal parameters of thyroid nodules show little influence on surface infrared emissions, for instance, those related to the vascularization of the nodule. All details of the physical parameters used in the simulations, characteristics of the real nodules and thermal examinations are publicly available, allowing these simulations to be compared with other types of heat transfer solutions and infrared examination protocols. Among the main contributions of this work, we highlight the simulation of the possible range of parameters, and definition of the simulation approach for mapping the used infrared protocol, promoting the investigation of a possible relation between the heat transfer process and the data obtained by infrared acquisitions.

scholarly journals Bioinsecticides based on plant essential oils: a short overview

2020 ◽  
Vol 75 (7-8) ◽  
pp. 179-182
Author(s):  
Murray B. Isman
Keyword(s):  
Essential Oils ◽  
Crop Protection ◽  
Large Body ◽  
Regulatory Agencies ◽  
The European Union ◽  
Plant Essential Oils ◽  
The Past ◽  
Wide Range ◽  
The Usa ◽  
Regulatory Challenges

AbstractInterest in the discovery and development of plant essential oils for use as bioinsecticides has grown enormously in the past 20 years. However, successful commercialization and utilization of crop protection products based on essential oils has thus far lagged far behind their promise based on this large body of research, most notably because with the exceptions of the USA and Australia, such products receive no special status from regulatory agencies that approve new pesticides for use. Essential oil-based insecticides have now been used in the USA for well over a decade, and more recently have seen use in the European Union (EU), Korea, and about a dozen other countries, with demonstrated efficacy against a wide range of pests and in numerous crop systems. For the most part these products are based on commodity essential oils developed as flavor and fragrance agents for the food and cosmetic industries, as there are formidable logistic, economic, and regulatory challenges to the use of many other essential oils that otherwise possess potentially useful bioactivity against pests. In spite of these limitations, the overall prospects for biopesticides, including those based on essential oils, are encouraging as the demand for sustainably-produced and/or organic food continues to increase worldwide.

scholarly journals Modelling H2 and its effects on star formation using a joint implementation of gadget-3 and KROME

2021 ◽  
Vol 504 (2) ◽  
pp. 2325-2345
Author(s):  
Emanuel Sillero ◽  
Patricia B Tissera ◽  
Diego G Lambas ◽  
Stefano Bovino ◽  
Dominik R Schleicher ◽  
...  
Keyword(s):  
Star Formation ◽  
Formation Rate ◽  
Physical Parameters ◽  
Density Profiles ◽  
Star Forming ◽  
Chemical Enrichment ◽  
Numerical Resolution ◽  
Stellar Radiation ◽  
Wide Range ◽  
The Impact

ABSTRACT We present p-gadget3-k, an updated version of gadget-3, that incorporates the chemistry package krome. p-gadget3-k follows the hydrodynamical and chemical evolution of cosmic structures, incorporating the chemistry and cooling of H2 and metal cooling in non-equilibrium. We performed different runs of the same ICs to assess the impact of various physical parameters and prescriptions, namely gas metallicity, molecular hydrogen formation on dust, star formation recipes including or not H2 dependence, and the effects of numerical resolution. We find that the characteristics of the simulated systems, both globally and at kpc-scales, are in good agreement with several observable properties of molecular gas in star-forming galaxies. The surface density profiles of star formation rate (SFR) and H2 are found to vary with the clumping factor and resolution. In agreement with previous results, the chemical enrichment of the gas component is found to be a key ingredient to model the formation and distribution of H2 as a function of gas density and temperature. A star formation algorithm that takes into account the H2 fraction together with a treatment for the local stellar radiation field improves the agreement with observed H2 abundances over a wide range of gas densities and with the molecular Kennicutt–Schmidt law, implying a more realistic modelling of the star formation process.

scholarly journals Molecular Analysis of a Plum pox virus W Isolate in Plum Germplasm Hand Carried into the USA from the Ukraine Shows a Close Relationship to a Latvian Isolate

Plant Disease ◽  
2013 ◽  
Vol 97 (1) ◽  
pp. 44-52 ◽  
Author(s):  
Vessela Mavrodieva ◽  
Delano James ◽  
Karen Williams ◽  
Sarika Negi ◽  
Aniko Varga ◽  
...  
Keyword(s):  
United States ◽  
Genetic Diversity ◽  
The United States ◽  
Common Source ◽  
Plum Pox Virus ◽  
High Genetic Diversity ◽  
Close Relationship ◽  
The Usa ◽  
Sequence Identities ◽  
Germplasm Accessions

Four of 19 Prunus germplasm accessions hand carried from the Ukraine into the United States without authorization were found to be infected with Plum pox virus (PPV). Of the three isolates characterized, isolates UKR 44189 and UKR 44191 were confirmed to be isolates of PPV strain W, and UKR 44188 was confirmed to be an isolate of PPV strain D. UKR 44189 and UKR 44191 are very closely related to the PPV strain W isolate LV-145bt (HQ670748) from Latvia. Nucleotide and amino acid sequence identities between these three isolates were greater than 99%. This indicates that the isolates are very closely related and likely originated from a common source. The high genetic diversity among PPV-W strain isolates allowed the identification of potential recombination events between PPV isolates. It appears also that GF 305 peach and Prunus tomentosa are not hosts for the PPV isolate UKR 44189.

Sign in / Sign up

Export Citation Format

Share Document