scholarly journals Preliminary study of canker disease for development of urban tree health standard in Malaysia

2021 ◽  
Vol 918 (1) ◽  
pp. 012037
Author(s):  
R Terhem ◽  
N I M Alias ◽  
K A Kamarudzaman
Keyword(s):  
Urban Areas ◽  
Plant Pathogens ◽  
Mangifera Indica ◽  
Eucalyptus Camaldulensis ◽  
Assessment Procedure ◽  
Quality Of Data ◽  
Canker Disease ◽  
Ceratocystis Wilt ◽  
Starting Point ◽  
Assessment Standard

Abstract Canker disease (CD) mainly infected trees planted in urban areas in Malaysia. This disease is caused by several plant pathogens and may cause tree death and tree failure. The aims of this study are to identify tree species which are susceptible to canker diseases and to identify the causal agents especially plant pathogens of the disease. To perform the study, a survey on planted trees in several urban parks and sites in Malaysia were conducted. In this study, the Canker Disease (CD) assessment procedure was developed and modified from Thousand Cankers Disease Survey Guidelines by the United State Department of Agriculture (USDA). Later, the assessment procedure was improved based on surveys in the ground to fit and get the best quality of data from the observations. As a result, several canker diseases were identified on twenty-three (23) trees, the species were, Acacia sp, Bucida molineti, Cinnamomum iners, Citrus sp, Eucalyptus urograndis, Eucalyptus camaldulensis, Eucalyptus sp, Khaya grandifoliola, Mangifera indica, Manilkara zapota, Mimusops elengi, Peltophorum indicus, Samanea saman, Swietenia macrophylla, Swietenia spicifera, Tabebuia argentea, Terminalia catappa, Terminalia mantaly, Araucaria heterophylla, Casuarina equisetifolia, Gymnostoma sumatrana and Polyalthia longifolia. Based on symptom development the canker diseases known as Sphaeropsis canker, Cryphonectria canker, Chrysoporthe canker, Biscogniauxia canker, Hypoxylon canker, Cypress canker, Nectria canker, Ceratocystis Wilt, Pink disease, and Slime flux disease. This study can be the starting point in developing the Canker Disease (CD) Assessment Standard in Malaysia. It is important for Malaysia to have a Canker Disease (CD) Assessment Standard in order to become a guideline for future study or research that specifies canker disease towards common trees planted in Malaysia especially the urban areas.

Night-time chemistry of biomass burning plumes in urban areas: A dual mobile chamber study

2021 ◽  
Author(s):  
Spiro Jorga ◽  
Kalliopi Florou ◽  
Christos Kaltsonoudis ◽  
John Kodros ◽  
Christina Vasilakopoulou ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Urban Areas ◽  
Mass Spectra ◽  
Prescribed Burning ◽  
Organic Aerosol ◽  
Photochemical Activity ◽  
Organic Nitrate ◽  
Night Time ◽  
Starting Point ◽  
High Concentrations

<p>Biomass burning including residential heating, agricultural fires, prescribed burning, and wildfires is a major source of gaseous and particulate pollutants in the atmosphere. Although, important changes in the size distributions and the chemical composition of the biomass burning aerosol during daytime chemistry have been observed, the corresponding changes at nighttime or in winter where photochemistry is slow, have received relatively little attention. In this study, we tested the hypothesis that nightime chemistry in biomass burning plumes can be rapid in urban areas using a dual smog chamber system.</p><p> </p><p>Ambient urban air during winter nighttime periods with high concentrations of ambient biomass burning organic aerosol is used as the starting point. Ozone was added in the perturbed chamber to simulate mixing with background air (and subsequent NO<sub>3</sub> production and aging) while the second chamber was used as a reference. Following the injection of ozone rapid organic aerosol (OA) formation was observed in all experiments leading to increases of the OA concentration by 20-70%. The oxygen to carbon ratio of the OA increased by 50% on average and the mass spectra of the produced OA was quite similar to that of the oxidized OA mass spectra reported during winter in urban areas. Good correlation was also observed with the produced mass spectra from nocturnal aging of laboratory biomass burning emissions showing the strong contribution of biomass burning emissions in the SOA formation during cold nights with high biomass burning activities. Concentrations of NO<sub>3</sub> radicals as high as 25 ppt were measured in the perturbed chamber with an accompanying production of 0.2-1.2 μg m<sup>-3</sup> of organic nitrate. These results strongly indicate that the OA in biomass burning plumes can evolve rapidly even during wintertime periods with low photochemical activity.</p>

scholarly journals Experimental and artificial neural network approach for forecasting of traffic air pollution in urban areas: The case of Subotica

2010 ◽  
Vol 14 (suppl.) ◽  
pp. 79-87 ◽  
Author(s):  
Bogdana Vujic ◽  
Srdjan Vukmirovic ◽  
Goran Vujic ◽  
Nebojsa Jovicic ◽  
Gordana Jovicic ◽  
...  
Keyword(s):  
Air Pollution ◽  
Urban Areas ◽  
Meteorological Data ◽  
Model Development ◽  
Ambient Air ◽  
Ann Model ◽  
Statistical Parameters ◽  
Neural Network Approach ◽  
Starting Point ◽  
Artificial Neural

In the recent years, artificial neural networks (ANNs) have been used to predict the concentrations of various gaseous pollutants in ambient air, mainly to forecast mean daily particle concentrations. The data on traffic air pollution, irrespective of whether they are obtained by measuring or modelling, represent an important starting point for planning effective measures to improve air quality in urban areas. The aim of this study was to develop a mathematical model for predicting daily concentrations of air pollution caused by the traffic in urban areas. For the model development, experimental data have been collected for 10 months, covering all four seasons. The data about hourly concentration levels of suspended particles with aerodynamic diameter less than 10 ?m (PM10) and meteorological data (temperature, air humidity, speed and direction of wind), measured at the measuring station in the town of Subotica from June 2008 to March 2009, served as the basis for developing an ANN-based model for forecasting mean daily concentrations of PM10. The quality of the ANN model was assessed on the basis of the statistical parameters, such as RMSE, MAE, MAPE, and r.

scholarly journals Treatments’ Complexity in Dental Care Assistance, Urban Versus Rural Environment - Preliminary Study

2021 ◽  
Vol 26 (1) ◽  
pp. 75-78
Author(s):  
Camelia Ionescu ◽  
Mădălina Adriana Malița ◽  
Viorel Ștefan Perieanu ◽  
Mihai Burlibașa ◽  
Magdalena Natalia Dina ◽  
...  
Keyword(s):  
Dental Care ◽  
Urban Areas ◽  
Rural Environment ◽  
Facial Region ◽  
Starting Point ◽  
Preliminary Study ◽  
Dental Offices ◽  
Care Assistance ◽  
Urban Versus ◽  
Made In

Abstract When talking about dental assistance we actually refer to the prevention, detection and treatment of diseases of the oral and maxillo-facial region which, in most cases, have as a starting point or interest the dento-maxillary system. In this material, we tried to present a comparative study on the typology and complexity of different stages of dental treatments that can be performed in urban areas, compared to various stages of dental treatments that are performed and / or could be made in rural dental offices from in Romania.

scholarly journals Housing Resources and Needs in Light of Modern Urban Transformations: the Case of Poznan

2017 ◽  
Vol 25 (2) ◽  
pp. 72-78
Author(s):  
Sławomir Palicki
Keyword(s):  
Urban Sprawl ◽  
Urban Areas ◽  
Local Governments ◽  
Real Estate Market ◽  
Capital City ◽  
Central Cities ◽  
The Real Estate ◽  
Suburban Areas ◽  
Starting Point ◽  
Urban Transformations

Abstract Polish cities have been at the stage of a dynamic suburban development for over a decade (which has led to the phenomenon of urban sprawl beyond any control). The population of big urban areas, together with their agglomerations is continuously increasing; however, migration tendencies towards suburban areas are strong as well. In such a situation, the question arises regarding the possibilities and the methods of suppressing the outflow of people to the neighboring communities, and once again, making the city an attractive place to live. The attempt to explain such an issue requires research into both the housing infrastructure and its inhabitants. Poznan has been severely affected by suburbanization. The diagnosis and assessment of Poznan housing resources and the preferences of its inhabitants are the starting point for taking further steps in making the housing conditions more attractive. The article shows the initial results of widespread research regarding housing in the capital city of the Wielkopolska Province (comprising over 2,500 households). A similar study for the entire agglomeration (Poznan County) is due to be completed soon. It will allow for a comparative analysis and formulating recommendations regarding the conditions and the direction of changes on the real estate market which would increase the attractiveness of central cities suffering from suburbanization. In a wider context, the publication might be seen as an analysis of one of the elements of modern urban changes, such as either market driven, or free and spontaneous processes of urban sprawl, and conscious actions taken by local governments (together with developers) regarding the integrated urban revitalization policy.

scholarly journals Tecnologias digitais no ensino de história e valorização do patrimônio cultural da Amazônia brasileira / Digital Technologies in History Teaching and Valorization of Cultural Heritage in Brazilian Amazon

2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Benedito Walderlino De Souza Silva
Keyword(s):  
Cultural Heritage ◽  
Urban Areas ◽  
Teaching And Learning ◽  
Digital Technologies ◽  
Brazilian Amazon ◽  
Starting Point ◽  
Cultural Appreciation ◽  
On Line ◽  
America Latina ◽  
Artistic Heritage

ABSTRACTThis article focuses on conceptual and methodological issues concerning the contribution that digital technologies can provide to School education in the context of the teaching and learning of history in matters related to cultural heritage process. Brazil has the “Instituto do Patrimônio Histórico e Artístico Nacional” (Institute of National Historical and Artistic Heritage) to implement public policies in order to to preserve their culture. In partnership with the “Universidade Federal do Pará” (Federal University of Pará), the unit of the institute in the state of Pará has developed a tool of heritage education called “Ver-o-Site”, an online page with the objective of increasing the cultural appreciation of Ver-o-Peso, the largest free fair in Latin America, a cultural and touristical symbol, and also the starting point of this state capital, the city of Belém. As we evaluate the considerable importance that digital technologies like this have on students' lives, creating new forms and speed of access and sharing of information, we consider that educators must use them as educational tools. With the Ver-oSite, you can work aspects of colonial occupation process, historical, economic and social development of urban areas in the Brazilian Amazon, as well as the space that places like the Ver-o-Peso occupy in the cultural heritage of inhabitants of cities like Belém. Such action aims to strengthen the role of social formation of the school with students in the digital age.RESUMOEste trabalho objetiva discutir fundamentos conceituais e teórico-metodológicos relativos à contribuição que tecnologias digitais podem fornecer a educação escolar no contexto do processo de ensino-aprendizagem da disciplina história em assuntos relacionados ao patrimônio cultural. O Brasil conta com o Instituto do Patrimônio Histórico e Artístico Nacional para executar políticas públicas de preservação de sua cultura. Em parceria com a Universidade Federal do Pará, a unidade do instituto no Estado Pará desenvolveu uma ferramenta de educação patrimonial chamada Ver-o-Site, uma página on-line voltada à valorização cultural do Ver-o-Peso, a maior feira livre da América Latina, símbolo cultural, turísti-co e ponto de origem da capital deste estado, a cidade de Belém. Avaliando o espaço considerável que tecnologias digitais como esta têm na vida dos alunos, gerando novas formas e velocidade de acesso e socialização de informação, pondera-se que os educadores devam utilizá-las como ferramentas educativas. Com o Ver-o-Site, pode-se trabalhar aspectos do proces-so de ocupação colonial, formação histórica, econômica e social de núcleos urbanos da Amazônia brasileira, bem como o espaço que lugares como o Ver-o-Peso ocupam no patrimônio cultural de habitantes de cidades como Belém. Tal ação visa fortalecer o papel de formação social da escola junto aos alunos na era digital. Contato principal: [email protected]

Evaluation of droplet digital PCR for the detection of black canker disease in tomato

Plant Disease ◽  
2021 ◽  
Author(s):  
Li Wang ◽  
Tian Qian ◽  
Pei Zhou ◽  
Wenjun Zhao ◽  
Xianchao Sun
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Plant Pathogens ◽  
Plant Protection ◽  
Detection Threshold ◽  
Digital Pcr ◽  
Taqman Probe ◽  
Tomato Seed ◽  
Canker Disease ◽  
Probe Set

Clavibacter michiganensis subsp. michiganensis (Cmm), the cause of bacterial canker disease, is one of the most destructive pathogens in greenhouse and field tomato. The pathogen is now present in all main production areas of tomato and is quite widely distributed in the EPPO（European and Mediterranean Plant Protection Organization）region. The inspection and quarantine of the plant pathogens relies heavily on accurate detection tools. Primers and probes reported in previous studies do not distinguish the Cmm pathogen from other closely related subspecies of C. michiganensis, especially the non-pathogenic subspecies that were identified from tomato seeds recently. Here, we have developed a droplet digital polymerase chain reaction (ddPCR) method for the identification of this specific bacterium with primers/TaqMan probe set designed based on the pat-1 gene of Cmm. This new primers/probe set has been evaluated by qPCRthe real time PCR（qPCR） and ddPCR. The detection results suggest that the ddPCR method established in this study was highly specific for the target strains. The result showed the positive amplification for all 5 Cmm strains，and no amplification was observed for the other 43 tested bacteria, including the closely related C. michiganensis strains. The detection threshold of ddPCR was 10.8 CFU/mL for both pure Cmm cell suspensions and infected tomato seed, which was 100 times-fold more sensitive than that of the real-time PCR (qPCR ) performed using the same primers and probe. The data obtained suggest that our established ddPCR could detect Cmm even with low bacteria load, which could facilitate both Cmm inspection for pathogen quarantine and the routine pathogen detection for disease control of black canker in tomato.

scholarly journals Exposure Indices of Extreme Wind-Driven Rain Events for Built Heritage

Atmosphere ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 163 ◽  
Author(s):  
Scott Allan Orr ◽  
May Cassar
Keyword(s):  
Cultural Heritage ◽  
Exposure Assessment ◽  
Urban Areas ◽  
Prolonged Exposure ◽  
Extreme Weather Events ◽  
Assessment Procedure ◽  
Statistical Confidence ◽  
Potential Impact ◽  
Rain Events ◽  
Two Stages

Building performance and material change of cultural heritage in urban areas are negatively impacted by wind-driven rain (WDR). The frequency and intensity of WDR exposure are modified by climate change. Current approaches to exposure assessment emphasise prolonged exposure. Here, we propose indices to represent the exposure of cultural heritage to extreme WDR events. The indices are derived in two stages: (1) time-binning of long-term exposure, and (2) statistical representation of the occurrence of infrequent but intense events by fitting to the Generalised Extreme Value (GEV) distribution. A comparison to an existing exposure assessment procedure demonstrates that the proposed indices better represent shorter, more intense, and more consistent WDR events. Indices developed for seasons had greater statistical confidence than those developed for annual exposure. One index is contextualised within a model of a gutter on a terraced building: this converts the index from a measure of exposure to potential impact. This evaluation demonstrated the importance of maintenance to reduce the potential impact of WDR events. This work has direct and indirect implications for developing robust assessment procedures for cultural heritage exposure to extreme weather events.

scholarly journals Two Dimensional Model for Backwater Geomorphology: Darby Creek, PA

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2204 ◽  
Author(s):  
Hosseiny ◽  
Smith
Keyword(s):  
Urban Areas ◽  
Water Surface ◽  
Integrated Model ◽  
Shear Stresses ◽  
Two Dimensional ◽  
Morphological Alterations ◽  
Digital Elevation ◽  
Starting Point ◽  
Spatio Temporal ◽  
Elevation Model

Predicting morphological alterations in backwater zones has substantial merit as it potentially influences the life of millions of people by the change in flood dynamics and land topography. While there is no two-dimensional river model available for predicting morphological alterations in backwater zones, there is an absolute need for such models. This study presents an integrated iterative two-dimensional fluvial morphological model to quantify spatio-temporal fluvial morphological alterations in normal flow to backwater conditions. The integrated model works through the following steps iteratively to derive geomorphic change: (1) iRIC model is used to generate a 2D normal water surface; (2) a 1D water surface is developed for the backwater; (3) the normal and backwater surfaces are integrated; (4) an analytical 2D model is established to estimate shear stresses and morphological alterations in the normal, transitional, and backwater zones. The integrated model generates a new digital elevation model based on the estimated erosion and deposition. The resultant topography then serves as the starting point for the next iteration of flow, ultimately modeling geomorphic changes through time. This model was tested on Darby Creek in Metro-Philadelphia, one of the most flood-prone urban areas in the US and the largest freshwater marsh in Pennsylvania.

scholarly journals Comparative Genomics and Phylogenetic Analyses Suggest Several Novel Species within the Genus Clavibacter, Including Nonpathogenic Tomato-Associated Strains

2020 ◽  
Vol 86 (6) ◽  
Author(s):  
Ebrahim Osdaghi ◽  
Touraj Rahimi ◽  
S. Mohsen Taghavi ◽  
Maryam Ansari ◽  
Sadegh Zarei ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Comparative Genomics ◽  
Plant Pathogens ◽  
Phylogenetic Analyses ◽  
Taxonomic Status ◽  
Sensu Stricto ◽  
Bacterial Canker ◽  
Agricultural Crops ◽  
Content Type ◽  
Canker Disease

ABSTRACT Members of the genus Clavibacter are economically important bacterial plant pathogens infecting a set of diverse agricultural crops (e.g., alfalfa, corn, potato, tomato, and wheat). Tomato-associated Clavibacter sp. strains account for a great portion of the genetic diversity of the genus, and C. michiganensis sensu stricto (formerly C. michiganensis subsp. michiganensis), causing bacterial canker disease, is considered one of the most destructive seed-borne agents for the crop worldwide. However, current taxonomic descriptions of the genus do not reflect the existing diversity of the strains, resulting in unsatisfactory results in quarantine surveys for the pathogens. In this study, we used all the available genome sequences of Clavibacter sp. strains, including the type strains of newly described subspecies, to provide precise insight into the diversity of tomato-associated members of the genus and further clarify the taxonomic status of the strains using genotypic and phenotypic features. The results of phylogenetic analyses revealed the existence of nine hypothetical new species among the investigated strains. None of the three new subspecies (i.e., C. michiganensis subsp. californiensis, C. michiganensis subsp. chilensis, and C. michiganensis subsp. phaseoli) is included within the tomato-pathogenic C. michiganensis sensu stricto lineage. Although comparative genomics revealed the lack of chp and tomA pathogenicity determinant gene clusters in the nonpathogenic strains, a number of pathogenicity-related genes were noted to be present in all the strains regardless of their pathogenicity characteristics. Altogether, our results indicate a need for a formal taxonomic reconsideration of tomato-associated Clavibacter sp. strains to facilitate differentiation of the lineages in quarantine inspections. IMPORTANCE Clavibacter spp. are economically important bacterial plant pathogens infecting a set of diverse agricultural crops, such as alfalfa, corn, pepper, potato, tomato, and wheat. A number of plant-pathogenic members of the genus (e.g., C. michiganensis sensu stricto and C. sepedonicus, infecting tomato and potato plants, respectively) are included in the A2 (high-risk) list of quarantine pathogens by the European and Mediterranean Plant Protection Organization (EPPO). Although tomato-associated members of Clavibacter spp. account for a significant portion of the genetic diversity in the genus, only the strains belonging to C. michiganensis sensu stricto (formerly C. michiganensis subsp. michiganensis) cause bacterial canker disease of tomato and are subjected to the quarantine inspections. Hence, discrimination between the pathogenic and nonpathogenic Clavibacter sp. strains associated with tomato seeds and transplants plays a pivotal role in the accurate detection and cost-efficient management of the disease. On the other hand, detailed information on the genetic contents of different lineages of the genus would lead to the development of genome-informed specific detection techniques. In this study, we have provided an overview of the phylogenetic and genomic differences between the pathogenic and nonpathogenic tomato-associated Clavibacter sp. strains. We also noted that the taxonomic status of newly introduced subspecies of C. michiganensis (i.e., C. michiganensis subsp. californiensis, C. michiganensis subsp. chilensis, and C. michiganensis subsp. phaseoli) should be reconsidered.

The Further Development of National Safety Assessment Standard for In-Service Pressure Equipment Containing Defects

2013 ◽  
Author(s):  
Shanshan Shao ◽  
Guodong Jia ◽  
Liang Sun ◽  
Hui Wang
Keyword(s):  
Economic Performance ◽  
Safety Assessment ◽  
Standard System ◽  
National Standard ◽  
Assessment Procedure ◽  
Assessment Techniques ◽  
International Structure ◽  
Assessment Standard ◽  
Further Development

The fitness-for-service assessment is widely used to demonstrate whether identified defects or in-service deterioration threaten the structure integrity of the pressure equipment. This article introduces the development of the Chinese national safety assessment standard. The assessment procedure and assessment techniques of current Chinese national safety assessment standard GB/T 19624-2004 are demonstrated, and the improvement is proposed. In order to maintain availability of aging equipment and enhance the long-term economic performance of in service pressure equipment, a new Chinese national safety assessment standard system is methodology proposed based on the analysis of some international structure integrity procedures or standards. A new national standard fitness-for-service which focuses on the evaluation of in-service damage and degeneration will be established while GB/T 19624 is applicable for general defects.

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