scholarly journals Natural Defect of a Plant Rhabdovirus Glycoprotein Gene: A Case Study of Virus–Plant Coevolution

2020 ◽  
pp. PHYTO-05-20-019 ◽  
Author(s):  
Song Zhang ◽  
Aijun Huang ◽  
Xin Zhou ◽  
Zhenghe Li ◽  
Ralf G. Dietzgen ◽  
...  

Seven isolates of a putative cytorhabdovirus (family Rhabdoviridae, order Mononegavirales) designated as citrus-associated rhabdovirus (CiaRV) were identified in citrus, passion fruit, and paper bush from the same geographical area in China. CiaRV, bean-associated cytorhabdovirus (Brazil), and papaya virus E (Ecuador) should be taxonomically classified in the species Papaya cytorhabdovirus. Due to natural mutations, the glycoprotein (G) and P4 genes were impaired in citrus-infecting isolates of CiaRV, resulting in an atypical rhabdovirus genome organization of 3′ leader-N-P-P3-M-L-5′ trailer. The P3 protein of CiaRV shared a common origin with begomoviral movement proteins (family Geminiviridae). Secondary structure analysis and trans-complementation of movement-deficient tomato mosaic virus and potato virus X mutants by CiaRV P3 supported its function in viral cell-to-cell trafficking. The wide geographical dispersal of CiaRV and related viruses suggests an efficient transmission mechanism, as well as an underlying risk to global agriculture. Both the natural phenomenon and experimental analyses demonstrated presence of the “degraded” type of CiaRV in citrus, in parallel to “undegraded” types in other host plant species. This case study shows a plant virus losing the function of an important but nonessential gene, likely due to host shift and adaption, which deepened our understanding of course of natural viral diversification.

2015 ◽  
Vol 3 (2) ◽  
pp. 55
Author(s):  
Norol Hamiza Zamzuri ◽  
Khairil Wahidin Awang ◽  
Yuhanis Abdul Aziz ◽  
Zaiton Samdin

The growth of the event sector is underpinned by the demand of organizing a business event.  Thus, it leads to an increase in economic and social impact. However, the problems from the growth of this sector potentially results from the use of several event materials, transportation and infrastructure development.  Organizing a green event is seen as one of the strategies to reduce the environmental impact.  Therefore, the aim of this paper is to explore the issues involved throughout the process of greening an event by applying Mair and Jago Model.  Semi-structured interviews were conducted with event managers from six Malaysia business event companies that encourage green practices during their event.  Findings suggest that impact, initiative, support and performance motivates event organizers in organizing a green event.  It has also been found that knowledge, resources and behaviour are the barriers faced by event organizers throughout the process of organizing a green event.  Based on the findings it appears that two important factors have emerged from the data collection and analysis that showed a deviation from the Mair and Jago Model, namely “impact” for the motivation element and “support” for the barrier element.  The main limitation of this study was the scope of the study; as it only focuses on business events.  However, as the main purpose of this study is to explore the issues of organizing a green event, it has been found that there are other issues need to be explored in other contexts and geographical area.  Apart from this, as this is a case study, it can only replicate according to the circumstances of this case study. However, this study can be generalized in terms of the theory that has emerged from it.  It is suggested that further research should explore more issues in other contexts and geographical areas. 


2016 ◽  
Vol 19 (2) ◽  
pp. 156-172 ◽  
Author(s):  
Chiara Rinaldi ◽  
Alessio Cavicchi

Purpose This paper aims to understand the motivations driving cooperative behaviour between heterogeneous stakeholders in place-branding activities, focusing on contract-based and relation-based cooperation constructs. Design/methodology/approach The longitudinal case study method is used to help understanding how the investigated network has evolved over four years from an attempt to build a regional umbrella-brand to a network contract between 13 enterprises. Findings The findings suggest that the relationships of trust and shared values among stakeholders are essential to foster cooperation, but also that contract-based governance complements a relation-based governance, enhancing the performance of the alliance. Research limitations/implications The main limitation is related to the case study methodology, as results are strongly dependent on the specific characteristics of the stakeholders and the geographical area analysed. Social implications The role of stakeholders in building a place brand is increasingly important. When analysing cooperative behaviour drivers, more attention should be paid to such intangible assets as social, human, relational and organisational capital. Originality/value This longitudinal case study emphasises that for success in place-branding activities, contract-based cooperation can be particularly useful at the beginning of a network alliance, while relation-based cooperation ensures the strength and continuity of the partnership but it takes time to develop. Responsible leaders, working as relationship facilitators/enablers, are important to keep network members engaged, by creating trust and favouring mutual beneficial relationships between stakeholders.


2018 ◽  
Vol 93 (5) ◽  
Author(s):  
Xiaoyun Wu ◽  
Jiahui Liu ◽  
Mengzhu Chai ◽  
Jinhui Wang ◽  
Dalong Li ◽  
...  

ABSTRACTPlant viruses usually encode one or more movement proteins (MP) to accomplish their intercellular movement. A group of positive-strand RNA plant viruses requires three viral proteins (TGBp1, TGBp2, and TGBp3) that are encoded by an evolutionarily conserved genetic module of three partially overlapping open reading frames (ORFs), termed the triple gene block (TGB). However, how these three viral movement proteins function cooperatively in viral intercellular movement is still elusive. Using a novelin vivodouble-stranded RNA (dsRNA) labeling system, we showed that the dsRNAs generated by potato virus X (PVX) RNA-dependent RNA polymerase (RdRp) are colocalized with viral RdRp, which are further tightly covered by “chain mail”-like TGBp2 aggregates and localizes alongside TGBp3 aggregates. We also discovered that TGBp2 interacts with the C-terminal domain of PVX RdRp, and this interaction is required for the localization of TGBp3 and itself to the RdRp/dsRNA bodies. Moreover, we reveal that the central and C-terminal hydrophilic domains of TGBp2 are required to interact with viral RdRp. Finally, we demonstrate that knockout of the entire TGBp2 or the domain involved in interacting with viral RdRp attenuates both PVX replication and movement. Collectively, these findings suggest that TGBp2 plays dual functional roles in PVX replication and intercellular movement.IMPORTANCEMany plant viruses contain three partially overlapping open reading frames (ORFs), termed the triple gene block (TGB), for intercellular movement. However, how the corresponding three proteins coordinate their functions remains obscure. In the present study, we provided multiple lines of evidence supporting the notion that PVX TGBp2 functions as the molecular adaptor bridging the interaction between the RdRp/dsRNA body and TGBp3 by forming “chain mail”-like structures in the RdRp/dsRNA body, which can also enhance viral replication. Taken together, our results provide new insights into the replication and movement of PVX and possibly also other TGB-containing plant viruses.


Federalism-E ◽  
1969 ◽  
Vol 5 (1) ◽  
pp. 64-67
Author(s):  
Jok Oga Ukelo

Black Africa has become the theatre of everlasting war. These are wars in which Africans massacre their brothers and plunder the natural resources of their continent. We can cite the cases of the Bakongo and the Bangala in the Congo Brazzaville or the Tutsis and the Hutu in Rwanda. In this article the questions surrounding the interethnic conflicts in the Democratic Republic of Congo, via a case study of the conflict between the Hema and Lendu in the Ituri region, are explored. The main thrust of the article is that the concept of good governance is linked to a sustainable developmental strategy and that this is the only way to reach peace in this geographical area.[...]


2006 ◽  
Vol 10 (4) ◽  
pp. 249-267 ◽  
Author(s):  
Tomi Ventovuori

The aim of this paper is to identify the different elements of the sourcing strategy decision‐making process and to clarify what are the factors that lead to the selection of a certain sourcing strategy in FM services. The study is based on a literature review and a multiple case study, which was conducted with four organizations representing different types of FM service clients. To find the optimal sourcing strategy and understand the consequences of different sourcing options, five decision categories must be analysed: sourcing interface, organizational decision‐making, the scope of service package, the geographical area of sourcing and relationship type. There are also some other elements that must be taken into account in the process of sourcing strategy development such as different elements of business in general and the prevailing market conditions. It is strongly suggested that companies could apply the presented integrated approach as a starting point for the development of sourcing strategies in FM services. In addition, this study shows that companies should view the development of sourcing strategies as an important phase of the procurement cycle.


2020 ◽  
Vol 13 (2) ◽  
pp. 564
Author(s):  
Renata Cristina Mafra ◽  
Mayara Maezano Faita Pinheiro ◽  
Rejane Ennes Cicerelli ◽  
Lucas Prado Osco ◽  
Marcelo Rodrigo Alves ◽  
...  

O processo erosivo é um fenômeno que acontece devido às condições climáticas ou uso inadequado da terra. O mapeamento dos níveis de vulnerabilidade à erosão de uma área pode ocorrer usando diferentes modelos de inferência geográfica. No entanto, definir o método apropriado é ainda uma questão a ser respondida. Este trabalho apresenta uma abordagem de validação de mapa de vulnerabilidade à erosão elaborado por diferentes métodos de inferência. Como estudo de caso, adotou-se uma bacia hidrográfica e considerou-se os seguintes critérios: geomorfologia, pedologia, declividade, densidade de drenagem e cobertura da terra. Dentre os métodos testados tem-se: Combinação Linear Ponderada (CLP) e três operadores Fuzzy: soma algébrica, produto algébrico e gamma, variando o expoente “γ” entre os valores 0,4; 0,6 e 0,8. Os pesos dos critérios foram definidos com base no Processo Analítico Hierárquico. A validação dos mapas ocorreu usando 1902 pontos, sendo 951 pontos de erosão na área, definidos com base em imagens do Google Earth Pro, e 951 pontos sem erosão, gerados aleatoriamente no QGIS 3.8. O modelo de regressão logística foi usado parar comparar o desempenho de cada mapa ao apontar as áreas com maior e menor grau de vulnerabilidade. A melhor modelagem foi alcançada com o operador Fuzzy gamma quando parametrizado com γ = 0,6. Embora o CLP seja a abordagem recorrente em estudos ambientais envolvendo inferência geográfica, nossos resultados demostram que outros operadores podem produzir resultados mais próximos aos encontrados com a realidade observada em campo.  Machine learning erosion and vulnerability map validation A B S T R A C TErosion is a natural phenomenon that happens in all ecosystems, whether due to weather conditions or inappropriate land use. Mapping the erosion vulnerability levels of an area can occur using different methods of geographic inference. However, defining the appropriate method is still a question to be answered. This paper presents an erosion vulnerability map validation approach elaborated by different inference methods. As a case study, a watershed was adopted and the following criteria were considered: geomorphology, pedology, slope, drainage density and land cover. Among the tested methods are: Weighted Linear Combination (WLC) and three Fuzzy operators: algebraic sum, algebraic product and gamma, varying the exponent “γ” between the values 0.4; 0.6 and 0.8. The weights of the criteria were defined based on the Hierarchical Analytical Process. The validation of the maps took place using 1902 points, with 951 erosion points in the area defined based on Google Earth Pro images and 951 points without erosion randomly generated in QGIS 3.8. The logistic regression model was used to compare the performance of each map by pointing out the areas with the highest and lowest degree of vulnerability. The best modeling was achieved with the Fuzzy gamma operator when parameterized with γ = 0.6. Although WLC is the recurring approach in environmental studies involving geographic inference, our results show that other operators can produce results closer to those encountered with the reality observed in the field.Keywords: Geographical inference; multicriteria analysis; data validation; environmental impact.


2017 ◽  
Vol 3 (3) ◽  
pp. 14 ◽  
Author(s):  
Frank Cremer ◽  
Muktha Muralee

Atmospheric emissions such as NOx from ship engines have a drastic impact on the environment. Controlling them is crucial for maintaining a sustainable growth for any logistics company. The Port of Rotterdam (The Netherlands) is using big data analytics to gain actionable insights into these emissions. Our case study deals with the implementation of the emission calculations and reporting implemented in Hadoop. In the analytical setup we introduce the method for estimating emissions based on recorded ship position data and information about its engines. We present a flexible approach that stores intermediate results allowing different levels of aggregation. These levels of aggregations are per geographical area, per grid or for a whole journey attributed to each visited berth. The results are visualized in a Geographical Information System (GIS). The estimated atmospheric emissions also serves as input for the deposition model. We present some selected results of emissions per grid as well as for pre-defined areas. These results are used by the port to make strategic decision. For future work we recommend to also implement the deposition model in Hadoop as this model is also calculative intensive and therefore it currently only accepts aggregated emissions as input, whereby its accuracy is most likely reduced.


Geophysics ◽  
2018 ◽  
Vol 83 (2) ◽  
pp. B59-B76 ◽  
Author(s):  
Amir Haroon ◽  
Klaus Lippert ◽  
Vladimir Mogilatov ◽  
Bülent Tezkan

The marine differential electric dipole (DED) is applied for the first time to study a subseafloor groundwater body in the coastal region of Bat Yam, Israel. Previous marine long-offset transient electromagnetic applications detected this freshwater body underneath the Mediterranean seafloor. We have applied the novel DED method for the first time in the marine environment to further investigate this natural phenomenon. The main objectives are to locate the freshwater-seawater interface at the western aquifer edge and to identify the mechanism controlling this freshwater occurrence beneath the seafloor. The acquired step-on signals allow one to detect the freshwater body in the vicinity of the Israeli coastline at a depth of approximately 70 m beneath the seafloor. However, aquifer thickness is only poorly determined and may vary between 40 and 100 m. A lateral resistivity contrast is observable between adjacent 1D inversion models and also apparent in data profile curves that constrain the seaward extent of the detected resistive body to a distance of less than 4 km from the coastline. A subsequent 2.5D forward-modeling study aims to find a subseafloor resistivity distribution that adequately explains all measured DED data simultaneously. The results further constrain the lateral extent of the resistive aquifer to approximately 3.6–3.7 km from the Israeli coast. Furthermore, the data indicate that the aquifer system may be susceptible to seawater intrusion, as a superior data fit is achieved if a brackish water zone of approximately [Formula: see text] with a lateral extent of less than 300 m is located at the head of the freshwater body.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sanduni Peiris ◽  
Nayanthara De Silva

Purpose Factory acceptance testing (FAT) in the construction industry has been severely hampered due to restrictions in cross-border travel resulting from the COVID-19 pandemic. Consequently, virtual FAT (vFAT) became a popular substitute for physical FAT. However, the credibility of vFAT is being questioned because it was adopted without much scrutiny. Hence, this study is aimed at investigating vFATs and re-engineering the FAT process to suit an effective vFAT environment.Design/methodology/approach A comprehensive literature search on FAT procedures was followed by two stages of expert interviews with eight leading subject experts and a case study. The findings were analysed using code-based content analysis on NVivo software.Findings Strengths of vFATs include “reduction in cost and time consumed”, “flexibility for more participants” and “faster orders”. Most emphasized weaknesses include “lack of reliability” and “lack of technology transfer”. vFAT has mostly increased test reliability by “improving accessibility” and has decreased reliability by “restricting physical touch and feel observation of the equipment”. A four-step vFAT process was developed with a noteworthy additional step called “Pre-FAT Meeting”.Research limitations/implications The scope of this study is limited to the Sri Lankan construction industry. Expansion of the geographical area of focus is recommended for future studies.Originality/value The findings of this study unveil a vFAT process, which is timely and beneficial for construction practitioners to optimize and enhance the effectiveness of vFATs which are currently conducted in a disarranged manner.


2006 ◽  
Vol 31 (1) ◽  
pp. 31-38
Author(s):  
Kurt Rhyner

Disasters are always caused by a combination of factors, and the natural phenomenon that brings them on is usually just a catalyst. The underlying cause of most disasters is poverty as mostly the poor segments of the population usually live in high risk areas where their shelter all too often cannot withstand even light winds, small inundations or medium earthquakes. When Hurricane Mitch hit Central America in October 1998, all countries were ill prepared. A few weeks earlier, the authorities of the Honduran capital, Tegucigalpa, had attempted to simulate an evacuation, but it had met with a great degree of resistance from the public. When Mitch hit, unprecedented masses of water raced down the mountainous river beds. People were taken by surprise, as no efficient organisation existed. Everybody ran for their lives. Houses slid down hillsides, rivers swept bridges, houses and people with them. Six years later, Tegucigalpa looks very similar to the days before Mitch. The steep hillsides are covered with a potpourri of dwellings, from miserable huts to solid upmarket houses. Regulations were passed in the year 2002 to prohibit construction in high risk areas; however, enforcement is difficult, especially when existing buildings are renovated and even enlarged. Theoretically it is possible to evacuate high risk areas. Nonetheless, such drastic measures are virtually impossible to implement, as no mayor or police chief would survive such an action in office. The paper presents a case study which shows that the underlying problems of poverty and the non-availability of suitable land for people to relocate from high risk areas can usually not be overcome by post-disaster reconstruction programmes. A mitigation strategy is thus to empower inhabitants of high risk areas to improve their own situation by affordable access to information, advice and suitable low cost construction materials through “Building Advisory Services” and Ecomaterials producers within the neighbourhoods.


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