scholarly journals Rickettsia in the whitefly Bemisia tabaci: Phenotypic variants and fitness effects

2014 ◽  
Author(s):  
Martha S. Hunter ◽  
Einat Zchori-Fein
Keyword(s):  
United States ◽  
Bemisia Tabaci ◽  
Horizontal Transmission ◽  
Critical Role ◽  
Large Change ◽  
The United States ◽  
Bacterial Symbionts ◽  
Fitness Effects ◽  
Accelerated Evolution ◽  
The Usa

The sweet potato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is a major pest of vegetables, field crops, and ornamentals worldwide. This species harbors a diverse assembly of facultative, “secondary” bacterial symbionts, the roles of which are largely unknown. We documented a spectacular sweep of one of these, Rickettsia, in the Southwestern United States in the B biotype (=MEAM1) of B. tabaci, from 1% to 97% over 6 years, as well as a dramatic fitness benefit associated with it in Arizona but not in Israel. Because it is critical to understand the circumstances in which a symbiont invasion can cause such a large change in pest life history, the following objectives were set: 1) Determine the frequency of Rickettsia in B. tabaci in cotton across the United States and Israel. 2) Characterize Rickettsia and B. tabaci genotypes in order to test the hypothesis that genetic variation in either partner is responsible for differences in phenotypes seen in the two countries. 3) Determine the comparative fitness effects of Rickettsia phenotypes in B. tabaci in Israel and the United States. For Obj. 1, a survey of B. tabaci B samples revealed the distribution of Rickettsia across the cotton-growing regions of 13 sites from Israel and 22 sites from the USA. Across the USA, Rickettsia frequencies were heterogeneous among regions, but were generally at frequencies higher than 75% and close to fixation in some areas, whereas in Israel the infection rates were lower and declining. The distinct outcomes of Rickettsia infection in these two countries conform to previouslyreported phenotypic differences. Intermediate frequencies in some areas in both countries may indicate a cost to infection in certain environments or that the frequencies are in flux. This suggests underlying geographic differences in the interactions between bacterial symbionts and the pest. Obj. 2, Sequences of several Rickettsia genes in both locations, including a hypervariableintergenic spacer gene, suggested that the Rickettsia genotype is identical in both countries. Experiments in the US showed that differences in whitefly nuclear genotype had a strong influence on Rickettsia phenotype. Obj. 3. Experiments designed to test for possible horizontal transmission of Rickettsia, showed that these bacteria are transferred from B. tabaci to a plant, moved inside the phloem, and could be acquired by other whiteflies. Plants can serve as a reservoir for horizontal transmission of Rickettsia, a mechanism that may explain the occurrence of phylogenetically-similarsymbionts among unrelated phytophagous insect species. This plant-mediated transmission route may also exist in other insect-symbiont systems, and since symbionts may play a critical role in the ecology and evolution of their hosts, serve as an immediate and powerful tool for accelerated evolution. However, no such horizontal transmission of Rickettsia could be detected in the USA, underlining the difference between the interaction in both countries, or between B. tabaci and the banded wing whitefly on cotton in the USA (Trialeurodes sp. nr. abutiloneus) and the omnivorous bug Nesidiocoristenuis. Additionally, a series of experiments excluded the possibility that Rickettsia is frequently transmitted between B. tabaci and its parasitoid wasps Eretmocerusmundus and Encarsiapergandiella. Lastly, ecological studies on Rickettsia effects on free flight of whiteflies showed no significant influence of symbiont infection on flight. In contrast, a field study of the effects of Rickettsia on whitefly performance on caged cotton in the USA showed strong fitness benefits of infection, and rapid increases in Rickettsia frequency in competition population cages. This result confirmed the benefits to whiteflies of Rickettsia infection in a field setting.

scholarly journals Horizontal transmission of the insect symbiont Rickettsia is plant-mediated

2011 ◽  
Vol 279 (1734) ◽  
pp. 1791-1796 ◽  
Author(s):  
Ayelet Caspi-Fluger ◽  
Moshe Inbar ◽  
Netta Mozes-Daube ◽  
Nurit Katzir ◽  
Vitaly Portnoy ◽  
...  
Keyword(s):  
Horizontal Transmission ◽  
Critical Role ◽  
Blood Feeding ◽  
High Rate ◽  
Phytophagous Insects ◽  
Cotton Leaf ◽  
Bacterial Symbionts ◽  
Phytophagous Insect ◽  
Black Nightshade ◽  
Accelerated Evolution

Bacteria in the genus Rickettsia , best known as vertebrate pathogens vectored by blood-feeding arthropods, can also be found in phytophagous insects. The presence of closely related bacterial symbionts in evolutionarily distant arthropod hosts presupposes a means of horizontal transmission, but no mechanism for this transmission has been described. Using a combination of experiments with live insects, molecular analyses and microscopy, we found that Rickettsia were transferred from an insect host (the whitefly Bemisia tabaci ) to a plant, moved inside the phloem, and could be acquired by other whiteflies. In one experiment, Rickettsia was transferred from the whitefly host to leaves of cotton, basil and black nightshade, where the bacteria were restricted to the phloem cells of the plant. In another experiment, Rickettsia -free adult whiteflies, physically segregated but sharing a cotton leaf with Rickettsia -plus individuals, acquired the Rickettsia at a high rate. Plants can serve as a reservoir for horizontal transmission of Rickettsia , a mechanism which may explain the occurrence of phylogenetically similar symbionts among unrelated phytophagous insect species. This plant-mediated transmission route may also exist in other insect–symbiont systems and, since symbionts may play a critical role in the ecology and evolution of their hosts, serve as an immediate and powerful tool for accelerated evolution.

Emigrant Psychoanalysts in the USA and the FBI Archives

2004 ◽  
Vol 6 (1) ◽  
pp. 75-92 ◽  
Author(s):  
James E. Goggin
Keyword(s):  
United States ◽  
Civil Rights ◽  
National Socialism ◽  
Cultural Context ◽  
Due Process ◽  
The United States ◽  
External Threats ◽  
The Usa ◽  
The Rich ◽  
New Nation

Interest in the fate of the German psychoanalysts who had to flee Hitler's Germany and find refuge in a new nation, such as the United States, has increased. The ‘émigré research’ shows that several themes recur: (1) the theme of ‘loss’ of one's culture, homeland, language, and family; and (2) the ambiva-lent welcome these émigrés received in their new country. We describe the political-social-cultural context that existed in the United States during the 1930s, 1940s and 1950s. Documentary evidence found in the FBI files of three émigré psychoanalysts, Clara Happel, Martin Grotjahn, and Otto Fenichel, are then presented in combination with other source material. This provides a provisional impression of how each of these three individuals experienced their emigration. As such, it gives us elements of a history. The FBI documents suggest that the American atmosphere of political insecurity and fear-based ethnocentric nationalism may have reinforced their old fears of National Socialism, and contributed to their inclination to inhibit or seal off parts of them-selves and their personal histories in order to adapt to their new home and become Americanized. They abandoned the rich social, cultural, political tradition that was part of European psychoanalysis. Finally, we look at these elements of a history in order to ask a larger question about the appropriate balance between a liberal democratic government's right to protect itself from internal and external threats on the one hand, or crossover into the blatant invasion of civil rights and due process on the other.

Sandra Ramos Revisited

2020 ◽  
Vol 2 (4) ◽  
pp. 32-54
Author(s):  
Silvia Spitta
Keyword(s):  
United States ◽  
The United States ◽  
Ancient Greek ◽  
Graphic Arts ◽  
Left Behind ◽  
The World ◽  
The Usa ◽  
Political Choices ◽  
The Rich

Sandra Ramos (b. 1969) is one of the few artists to reflect critically on both sides of the Cuban di-lemma, fully embodying the etymological origins of the word in ancient Greek: di-, meaning twice, and lemma, denoting a form of argument involving a choice between equally unfavorable alternatives. Throughout her works she shines a light on the dilemmas faced by Cubans whether in Cuba or the United States, underlining the bad personal and political choices people face in both countries. During the hard 1990s, while still in Havana, the artist focused on the traumatic one-way journey into exile by thousands, as well as the experience of profound abandonment experienced by those who were left behind on the island. Today she lives in Miami and operates a studio there as well as one in Havana. Her initial disorientation in the USA has morphed into an acerbic representation and critique of the current administration and a deep concern with the environmental collapse we face. A buffoonlike Trumpito has joined el Bobo de Abela and Liborio in her gallery of comic characters derived from the rich Cuban graphic arts tradition where she was formed. While Cuba is now represented as a rotten cake with menacing flies hovering over it ready to pounce, a bombastic Trumpito marches across the world stage, trampling everything underfoot, a dollar sign for a face.

Russian Federation and the United States of America: geostrategic directions to manage the Ukrainian crisis

2019 ◽  
pp. 123
Author(s):  
Attarid Awadh Abdulhameed
Keyword(s):  
United States ◽  
European Union ◽  
National Security ◽  
Russian Federation ◽  
United States Of America ◽  
The United States ◽  
The European Union ◽  
The Usa ◽  
Ukrainian Crisis ◽  
Zero Sum

Ukrainia Remains of huge importance to Russian Strategy because of its Strategic importance. For being a privileged Postion in new Eurasia, without its existence there would be no logical resons for eastward Expansion by European Powers.  As well as in Connection with the progress of Ukrainian is no less important for the USA (VSD, NDI, CIA, or pentagon) and the European Union with all organs, and this is announced by John Kerry. There has always ben Russian Fear and Fear of any move by NATO or USA in the area that it poses a threat to  Russians national Security and its independent role and in funence  on its forces especially the Navy Forces. There for, the Crisis manyement was not Zero sum game, there are gains and offset losses, but Russia does not accept this and want a Zero Sun game because the USA. And European exteance is a Foot hold in Regin Which Russian sees as a threat to its national security and want to monopolize control in the strategic Qirim.

Interaction of Ukrainian Diaspora and the USA Government Regarding Celebration of Ukrainian Independence Day on January 22

2018 ◽  
Vol 1 (47) ◽  
pp. 136-145
Author(s):  
Halyna Shchyhelska
Keyword(s):  
United States ◽  
House Of Representatives ◽  
The United States ◽  
100Th Anniversary ◽  
Totalitarian Regime ◽  
The Public ◽  
Us Congress ◽  
The Us ◽  
Public Consciousness ◽  
The Usa

2018 marks the 100th anniversary of the proclamation of Ukrainian independence. OnJanuary 22, 1918, the Ukrainian People’s Republic proclaimed its independence by adopting the IV Universal of the Ukrainian Central Rada, although this significant event was «wiped out» from the public consciousness on the territory of Ukraine during the years of the Soviet totalitarian regime. At the same time, January 22 was a crucial event for the Ukrainian diaspora in the USA. This article examines how American Ukrainians interacted with the USA Government institutions regarding the celebration and recognition of the Ukrainian Independence day on January 22. The attention is focused on the activities of ethnic Ukrainians in the United States, directed at the organization of the special celebration of the Ukrainian Independence anniversaries in the US Congress and cities. Drawing from the diaspora press and Congressional Records, this article argues that many members of Congress participated in the observed celebration and expressed kind feelings to the Ukrainian people, recognised their fight for freedom, during the House of Representatives and Senate sessions. Several Congressmen submitted the resolutions in the US Congress urging the President of United States to designate January 22 as «Ukrainian lndependence Day». January 22 was proclaimed Ukrainian Day by the governors of fifteen States and mayors of many cities. Keywords: January 22, Ukrainian independence day, Ukrainian diaspora, USA, interaction, Congress

Microscale chemistry in the USA

2018 ◽  
Vol 10 (2) ◽  
pp. 107
Author(s):  
John H. Penn
Keyword(s):  
United States ◽  
The United States ◽  
Developmental Phase ◽  
Potential Development ◽  
Current Usage ◽  
The Usa ◽  
Early Developmental

<span>Microscale Chemistry has become the method of choice for the teaching laboratories in the United States. This introspective look at the development of microscale Chemistry details the advantages prornised by microscale Chemistry during the early developmental phase of microscale in the United States. These advantages are then compared to the current usage of microscale. This comparison is designed to highlight areas for potential development of the field.</span>

THE DEVELOPMENT OF ACCOUNTING AND INTERNAL CONTROL FOR THE NATIONAL LAND SYSTEM OF THE USA

1994 ◽  
Vol 21 (1) ◽  
pp. 189-213
Author(s):  
Michael P. Schoderbek
Keyword(s):  
United States ◽  
Internal Control ◽  
The United States ◽  
Record Keeping ◽  
Governmental Accounting ◽  
Land System ◽  
The Usa ◽  
And Control

This paper examines the early accounting practices that were used to administer the United States' national land system. These practices are of significance because they provide insights on early governmental accounting and they facilitated an orderly settlement of the western territories. The analysis focuses on the record-keeping and control practices that were developed to meet the provisions of the Land Act of 1800 and to account for land office transactions. These accounting procedures were extracted from the correspondence between the Department of the Treasury and the various land officers.

Building America

2019 ◽  
Author(s):  
Jean H. Baker
Keyword(s):  
United States ◽  
Early Republic ◽  
Critical Role ◽  
Water System ◽  
The United States ◽  
Primary Sources ◽  
Early American ◽  
Transatlantic Exchange ◽  
The Us ◽  
Private Homes

Building America: The Life of Benjamin Henry Latrobe is a biography of America’s first professionally trained architect and engineer. Born in 1764, Latrobe was raised in Moravian communities in England and Germany. His parents expected him to follow his father and brother into the ministry, but he rebelled against the church. Moved to London, he studied architecture and engineering. In 1795 he emigrated to the United States and became part of the period’s Transatlantic Exchange. Latrobe soon was famous for his neoclassical architecture, designing important buildings, including the US Capitol and Baltimore Basilica as well as private homes. Carpenters and millwrights who built structures more cheaply and less permanently than Latrobe challenged his efforts to establish architecture as a profession. Rarely during his twenty-five years in the United States was he financially secure, and when he was, he speculated on risky ventures that lost money. He declared bankruptcy in 1817 and moved to New Orleans, the sixth American city that he lived in, hoping to recoup his finances by installing a municipal water system. He died there of yellow fever in 1820. The themes that emerge in this biography are the critical role Latrobe played in the culture of the early republic through his buildings and his genius in neoclassical design. Like the nation’s political founders, Latrobe was committed to creating an exceptional nation, expressed in his case by buildings and internal improvements. Additionally, given the extensive primary sources available for this biography, an examination of his life reveals early American attitudes toward class, family, and religion.

Nutritional Marketing of Plant-Based Meat-Analogue Products: an exploratory study of front-of-pack and website claims in the USA

2021 ◽  
pp. 1-32
Author(s):  
Jennifer Lacy-Nichols ◽  
Libby Hattersley ◽  
Gyorgy Scrinis
Keyword(s):  
United States ◽  
The United States ◽  
Health Claims ◽  
Processed Foods ◽  
Nutrition And Health ◽  
Nutrition Claims ◽  
Health And Nutrition ◽  
Alternative Protein ◽  
Health Related ◽  
The Usa

Abstract Objective: To explore how some of the largest food companies involved in producing alternative proteins use health and nutrition claims to market their products. Design: We identified the largest food manufacturers, meat processors, and alternative protein companies selling plant-based alternative protein products in the United States. Using publicly available data, we analysed the voluntary health and nutrition claims made on front-of-pack labels and company webpages. We also analysed company websites for further nutrition and health-related statements about their products or alternative proteins more generally. Claim classification was guided by the INFORMAS (International Network for Food and Obesity/Non-Communicable Diseases Research, Monitoring, and Action Support) taxonomy for health-related food labelling. Setting: United States. Results: 1394 health and nutrition-related front-of-pack label (FOPL) claims were identified on 216 products, including 685 nutrition claims and 709 ´other health-related´ claims. No FOPL health claims were identified. Most nutrient claims were for nutrients associated with meat, with 94% of products carrying a protein claim and 30% carrying a cholesterol claim. 74% of products carried a GMO-free claim and 63% carried a plant-based claim. On their websites, some companies expanded on these claims or discussed the health benefits of specific ingredients. Conclusions: Companies involved in this category appear to be using nutritional marketing primarily to position their products in relation to meat. There is a focus on nutrient and ingredient claims, with discussion of processing largely avoided. The findings highlight the challenges companies face in positioning AP products as healthy against the backdrop of debates about ultra-processed foods.

scholarly journals Predicting the Dynamics of the COVID-19 Pandemic in the United States Using Graph Theory-Based Neural Networks

2021 ◽  
Vol 18 (7) ◽  
pp. 3834
Author(s):  
Mohammad Reza Davahli ◽  
Krzysztof Fiok ◽  
Waldemar Karwowski ◽  
Awad M. Aljuaid ◽  
Redha Taiar
Keyword(s):  
United States ◽  
Neural Networks ◽  
Graph Theory ◽  
Predictive Model ◽  
Short Term Memory ◽  
The United States ◽  
Graphical Analysis ◽  
Economic Consequences ◽  
Current Status ◽  
The Usa

The COVID-19 pandemic has had unprecedented social and economic consequences in the United States. Therefore, accurately predicting the dynamics of the pandemic can be very beneficial. Two main elements required for developing reliable predictions include: (1) a predictive model and (2) an indicator of the current condition and status of the pandemic. As a pandemic indicator, we used the effective reproduction number (Rt), which is defined as the number of new infections transmitted by a single contagious individual in a population that may no longer be fully susceptible. To bring the pandemic under control, Rt must be less than one. To eliminate the pandemic, Rt should be close to zero. Therefore, this value may serve as a strong indicator of the current status of the pandemic. For a predictive model, we used graph neural networks (GNNs), a method that combines graphical analysis with the structure of neural networks. We developed two types of GNN models, including: (1) graph-theory-based neural networks (GTNN) and (2) neighborhood-based neural networks (NGNN). The nodes in both graphs indicated individual states in the US states. While the GTNN model’s edges document functional connectivity between states, those in the NGNN model link neighboring states to one another. We trained both models with Rt numbers collected over the previous four days and asked them to predict the following day for all states in the USA. The performance of these models was evaluated with the datasets that included Rt values reflecting conditions from 22 January through 26 November 2020 (before the start of COVID-19 vaccination in the USA). To determine the efficiency, we compared the results of two models with each other and with those generated by a baseline Long short-term memory (LSTM) model. The results indicated that the GTNN model outperformed both the NGNN and LSTM models for predicting Rt.

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