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Seroprevalence and associated risk factors of Toxoplasma gondii infection in stray cats in Algiers urban area, Algeria

Seroprevalence and associated risk factors of Toxoplasma gondii infection in stray cats in Algiers urban area, Algeria

Toxoplasma to humans (Tenter et al., 2000; Dubey et al., 2009). In Algeria, cats mainly live outside like stray dogs where they hunt for food or live on waste. Even in- door cats are allowed to roam. Thus, the environment is likely to be contaminated by oocysts excreted by these cats. In recent years, the cat population has in- creased due to the accumulated attention paid to ani- mal welfare in cities. On the other hand, animals are highly respected in Algerian culture, so stray cats live freely in our environment. The aim of this study was to determine the seroprevalence of Toxoplasma IgG antibodies in cats in the urban area of Algiers, Algeria.
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Source apportionment vs. emission inventories of non-methane hydrocarbons (NMHC) in an urban area of the Middle East: local and global perspectives

Source apportionment vs. emission inventories of non-methane hydrocarbons (NMHC) in an urban area of the Middle East: local and global perspectives

year of 2010 according to the 2009 EMEP/EEA guidelines (EMEP/EEA 2009; Waked et al., 2012). The aim of this work is to identify major NMHC sources and quantify their contribution to NMHC concentrations on a seasonal basis by applying the source-receptor positive ma- trix factorization model (PMF) to the observations collected at a suburban site in the urban area of Beirut, Lebanon, and evaluate its consistency with existing emission inventories. The receptor modeling techniques are numerous; many of them have been previously used in NMHC source appor- tionment worldwide including principal component analysis (PCA), positive matrix factorization (PMF), chemical mass balance (CMB) and UNMIX like in Europe (Badol et al., 2008; Sauvage et al., 2009), the USA (Leuchner and Rap- penglück, 2010), and in China (Guo et al., 2007; Yuan et al., 2013). The performance of four receptor models (PCA, PMF, CMB and UNMIX) was evaluated by Miller et al. (2002) by applying them to the same artificial data set of VOCs. They found that PMF extracted factor profiles that most closely represented the major sources used to generate the simulated data, and concluded that PMF is the most appropriate model to explain the results (Miller et al., 2002).
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Urban area tomography using a sparse representation based two-dimensional spectral analysis technique

Urban area tomography using a sparse representation based two-dimensional spectral analysis technique

4.2.2. 3D View of the Building To demonstrate the potential of the CS 2D TomoSAR method for urban area analysis, we performed tomographic processing on a building (Figure 10 d). This target was selected because the coherence image of the target was structurally complete. Figure 12 a shows a 3D schematic representation of the building. The target building has two parts: one façade facing the illumination and a circular roof. The back façade was missed because the microwave is blocked by the front façade. Figure 12 b,d show the 3D visualization of the scatterers reconstructed with SAR tomography on the target building. Figure 12 b is the result of the CS 1D TomoSAR method, and 487 scatterers were reconstructed. Figure 12 c,d are the results of the CS 2D TomoSAR method with the range resolution enhanced by 1.5 times and 2 times, respectively. The results are consistent with the 3D schematic representation of the building. As before, with the improvements in range resolution, more scatterers on the target were reconstructed by the CS 2D TomoSAR method and nearly 691 and 832 scatterers were reconstructed where the range resolution was enhanced by 1.5 times and 2 times, respectively. Figure 13 shows a 3D visualization of the scatterers reconstructed with SAR tomography on the building zone. By using the CS 1D TomoSAR method, 7316 scatterers were reconstructed. However, when the range resolutions were enhanced by 1.5 times and 2 times by using the CS 2D TomoSAR method, 9709 and 12,205 scatterers were reconstructed, respectively.
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Towards Robust Analysis of Satellite Images Using Map Information - Application to Urban Area Detection

Towards Robust Analysis of Satellite Images Using Map Information - Application to Urban Area Detection

Towards Robust Analysis of Satellite Images Using Map Information — Application to Urban Area Detection Shan Yu, Marc Berthod, Gérard Giraudon.. apport de recherche..[r]

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Toward low energy cities : A case study of the urban area of Liège

Toward low energy cities : A case study of the urban area of Liège

A rate of renovation of buildings of 0.6% per year is chosen to simulate a realistic policy for energy renovation of the existing building stock equal to two thirds of the total rate of renovations observed in the Walloon Region on an annual basis. It is also assumed that the energy management is carried out efficiently: the oldest and least energy efficient buildings are the first to be renovated. Renovating of this old building stock will be incorporated as a reduction of 40% of energy consumption in comparison to the initial energy performance of these renovated buildings, which corresponds in the context of the urban area of Liège to the roof insulation of the individual terraced houses built before 1930 and to the roof insulation and the windows improvement of detached houses built between 1931 and 1969, not yet renovated. Following Verbeek and Hens (2005), insulation of the roof is the most effective and durable measure for energy performance increase of households in Belgium.
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Localization Precise in Urban Area

Localization Precise in Urban Area

 The GNSS-only block is always subject to environmental outliers, especially in an urban area.  Any failure in either GNSS-only block or in INS-only block will corrupt the whole system performance. The tight coupling (TC) makes the GNSS and INS fusion at the observables level. A TC KF is implemented to provide an integrated solution. As an integrated system, the TC provides a statistically rigorous sharing of information among states, especially those dedicated to INS-only block and GNSS- only block. Moreover, the process noise is only considered during the INS mechanization process other than in a LC the process noise is applied during both the INS mechanization and the GNSS-only propagation process [67]. The higher confidence on states increases the system ability to eliminate outliers. Finally, the most concerned case, a partial or full outage of GNSS in urban areas, herein does not need a reboot. A re-initialization may take the system tens of minutes to reach the steady-state performance. The implementation details of TC will be presented in the next section.
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Analysis of Visible/SWIR surface reflectance ratios for aerosol retrievals from satellite in Mexico City urban area

Analysis of Visible/SWIR surface reflectance ratios for aerosol retrievals from satellite in Mexico City urban area

A detailed analysis of the surface spectral reflectance over urban areas requires a high spatial resolution due to the heterogeneity of its surface cover. The National Consortium on Remote Sensing in Trans- portation (NCRST) from the University of California, Santa Barbara (http://www.ncgia.ucsb.edu/ncrst/resources/ easyread/HyperCenterlines/first.html), using the Airborne Visible InfraRed Imaging Spectrometer (AVIRIS) data, per- formed a detailed classification of the surface reflectance over Santa Barbara and Goleta urban area and identified dis- tinct surface types. Further analysis was also performed by Herold et al. (2003) using AVIRIS data for 2000. The sur- face reflectance of several surface types was derived by tak- ing advantage of the AVIRIS high spatial resolution (4 m) and 224 continuous spectral bands (0.40 to 2.50 µm). The analyzed surfaces include several vegetation types, soil and urban materials (asphalted or concreted roads, parking lots, roofs). The authors distinctively selected only homogeneous scenes in their analyses in order to characterize the specific targets since the 4 m resolution can still have a mix of differ- ent surface materials or shadows. Using their spectral data library categorized by different surface types, we computed the ρ surf (0.66 µm)/ρ surf (2.1 µm) ratio and plotted it against
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Modeling secondary organic aerosol in an urban area: application to Paris, France

Modeling secondary organic aerosol in an urban area: application to Paris, France

low-NO x conditions, oxidation by O 3 and by NO 3 ) and pro- cesses (condensation on an organic phase or an aqueous phase, oligomerization, hygroscopicity, and non-ideality). The H 2 O organic model has already been implemented in the Polyphemus air quality platform (Mallet et al., 2007) and evaluated over Europe from June 2002 to July 2003 (Couvi- dat et al., 2012). This evaluation showed that, even if H 2 O tends to underestimate organic carbon (OC) concentrations, it gives satisfactory results as the model performance criteria proposed by Boylan and Russell (2006) are met for OC con- centrations and as it almost achieves the model goal criteria. However, the model has not been evaluated at the scale of a city and the performance of the model over on urban area with fresh emissions from traffic is unknown. Therefore, we present here a model performance evaluation over a megac- ity: organic aerosols are simulated over the Paris area during July 2009 and are compared to the results of the Megapoli (Megacities: emissions, urban, regional and Global Atmo- spheric POLlution and climate effects, and Integrated tools for assessment and mitigation) campaign. The origins of or- ganic aerosols in Paris and the effect of a detailed treatment
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Partnership for local development : the case of the Belfort-Montbéliard-Héricourt urban area in the North-East of France

Partnership for local development : the case of the Belfort-Montbéliard-Héricourt urban area in the North-East of France

From 1984, members start working on common projects to give this area a new prospect of development. Taking advantage of the dynamics of the State policy in favour of universities, the domain of the higher education and research were the object of important investments. The association appears then as a place of mobilization and dialogue. A polytechnic institute is created in 1985, transformed since (1999) into university. In the cultural domain, local authorities financed collectively certain number of new structures (a scientific museum, an international centre of video creation). Joint operations to attract foreign companies were led by local agencies of economic development, cooperation in tourist subject was promoted between the tourist offices. It is also in the framework of the association that was negotiated the merger of the hospitals of Belfort and Montbéliard. The association was also used to promote the local interests at national and European level. The Urban Area obtained support from the European Fund for Regional Economic Development Objective 2, but also special State funds to help new firms to settle in the area.
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Measurements of nitrous acid (HONO) in urban area of Shanghai, China

Measurements of nitrous acid (HONO) in urban area of Shanghai, China

Atmospheric concentrations of HONO in Shanghai urban area have been recently reported in two studies (Hao et al. 2006; Wang et al. 2013). Both measurements have been carried out by the same DOAS technique. Concentration levels of HONO reached a maximum of  7 ppb, in agreement with previous observations in other large cities (Winer and Biermann 1994; Febo et al. 1996; Qin et al. 2009). These measurements in Shanghai (China) showed that the combination of surface and relative humidity promoted the heterogeneous conversion of NO 2 into HONO and would contribute to the observed
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Minimal Access Point Set in Urban Area Wifi Networks

Minimal Access Point Set in Urban Area Wifi Networks

Abstract—Faced by the large number of deployed Wifi Access Points (AP), many research efforts focus on energy savings in Wireless Local Networks. One of the most promising solutions for improving energy efficiency is the Sleep Mode approach, which is especially effective in dense deployments. It is based on switching off the APs while they are not in use, in order to avoid unnecessary energy consumption. In this paper we evaluate the poten- tial of switching off APs using real measurements taken in a dense urban area. We collected traces covering more than 20 hours, confirming the high density of currently deployed APs in such an environment. Based on these traces, we evaluate how many APs can be switched off while maintaining the same coverage. To this end, we propose two algorithms that select the minimum set of APs needed to provide full coverage. We compute sev- eral performance parameters, and evaluate the proposed algorithms in terms of the number of selected APs, and the coverage they provide. Our results show that between 4.25% and 10.91% of the detected APs are sufficient to provide the same coverage, depending on the data set, the mobile terminal and the AP selection algorithm.
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DTN Support for News Dissemination in an Urban Area

DTN Support for News Dissemination in an Urban Area

In this paper, we investigate the practicality of news dissemination over a DTN in an urban area. In DTNs, nodes can move freely and exchange content when they are within each other’s transmission range. Since an end-to-end path is not available most of the time, a store-carry-forward paradigm is usually used to enable communication. Several questions arose in the above setting in order to design a system that achieved the required service while avoiding deploying too many digital data kiosks. A first step would be to develop a quantitative analysis to investigate the message delay of DTNs. What are the most sensitive parameters: readers’ interest in content or contact opportunities? How effective can a DTN be without infrastructure? If the delay is found to be excessive, we suggest deploying some data kiosks in the environment to better support the dissemination of content. Data kiosks are simple devices that receive the content directly from the source, generally using wired or cellular networks. The question is how many data kiosks one has to invest in to satisfy performance constraints and where these data kiosks should be located. We are mostly interested in two performance metrics, the spreading time and the message delay. The message delay is the time needed to transmit content from a mobile node to another node, while the spreading time is the delay required to deliver the content to the last node in a group of nodes, or the time needed for the content to spread over a part of the network. The main question addressed in this paper is to determine the number of data kiosks necessary to disseminate content to a set of mobile nodes, when taking into account the spreading time in a given area and mobility pattern.
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Use of 3D classified topographic data with FullSWOF for high resolution simulation of a river flood event over a dense urban area

Use of 3D classified topographic data with FullSWOF for high resolution simulation of a river flood event over a dense urban area

These levels of errors and accuracy have been checked through terrestrial topo- graphic measurements effectuated by DIGNCA over 10% of the domain covered by the photogrammetric campaign. The number of class of elements created as vectorialized features is about 50. The high level of accuracy has allowed to photo-interpret thin above ground features as narrow as concrete walls and road gutters. Over the part of the low Var river area selected for the study, total number of polyline features represents more than 1 100 000 objects introduced under vector form.

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Parasite polymorphism and severe malaria in Dakar (Senegal): a West African urban area.

Parasite polymorphism and severe malaria in Dakar (Senegal): a West African urban area.

Urbanization profoundly changes the epidemiology of malaria, causing a decrease in risk, when compared to rural areas [1–3]. The Dakar area, with one-fifth of the Senegalese population, is a good example of this new setting, as it undergoes rapid urbanization and combines urban and peri-urban farming zones. Malaria transmis- sion used to occur near natural surface water collections (‘‘niayes’’), but a combination of drought (occurring during the last 30 years) and urbanization dramatic decreased this way of transmission. The parasitic index in children has fallen from 80% in 1967, to less than 10% in the 90’s [4], with only 10.6% of febrile illnesses due to
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PRODUCTION AND MANAGEMENT OF HOUSEHOLD WASTE IN THE URBAN AREA: the case of Adzopé city (CÔTE D'IVOIRE)

PRODUCTION AND MANAGEMENT OF HOUSEHOLD WASTE IN THE URBAN AREA: the case of Adzopé city (CÔTE D'IVOIRE)

Les études ont proposé des solutions de gestion des déchets urbains à partir de l’analyse des différents systèmes de gestion mis en place dans quelques grandes [r]

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High prevalence of kaolin consumption in migrant women living in a major urban area of France: A cross-sectional investigation

High prevalence of kaolin consumption in migrant women living in a major urban area of France: A cross-sectional investigation

* pascal.caillet@chu-nantes.fr Abstract Geophagia is a feeding behavior involving the regular intake of soil, including clay-like kao- lin. Frequent in Africa, kaolin consumption is associated with heavy metal intoxication, iron and other micronutrient deficiencies, geohelminth infection and inactivation of concomitantly taken drugs. It is expected that this practice would be imported into an asylum country dur- ing the immigration process. To confirm this hypothesis, a single center, cross-sectional study was conducted at the University Hospital of Nantes, France, whose main objective was to assess whether the prevalence of kaolin consumers was high in a migrant population living in a large French metropolitan area (the city of Nantes). Each woman consulting for the first time at the Medical and Psychosocial Gynecology Obstetric Unit during the inclusion period ranging from January 1, 2017, to July 1, 2017, was asked for consent to be included in the study. The main outcome was the proportion of positive answers regarding consump- tion of kaolin within the last twelve months, with its 95% confidence interval (CI). A logistic regression was performed to identify drivers of consumption, and a clustering approach was conducted to identify profiles of consumers. A total of 284 women were included in the study, of whom 110 (38.7%) were pregnant. Our main finding was a 14.1% (95% CI: 10.5– 18.6) prevalence of clay consumers. Second, the characteristic most strongly associated with consumption was Central or West Africa origin (adjusted Odds Ratio (aOR) = 52.7; 95% CI: 13.7–202.2). Finally, 60% of consumers showed signs of addictive-like phenom- ena, and three profiles were identified, depicting a continuum of patients in regard to their control over their kaolin consumption. Our results suggest that kaolin consumption is fre- quent in particular subpopulations of migrants. This warrants further study of the clinical con- sequences of kaolin consumption and its associated addictive-like symptoms.
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Multi-Level Morphometric Characterization of Built-up Areas and Change Detection in Siberian Sub-Arctic Urban Area: Yakutsk

Multi-Level Morphometric Characterization of Built-up Areas and Change Detection in Siberian Sub-Arctic Urban Area: Yakutsk

The second treated aspect of this study concerns the morphometric recognition and characterization of the settlements previously extracted by spectral indices. This additional and important step of the proposed methodology is part of the geographic object-based image analysis (GEOBIA) field [ 18 , 19 ], which considers the image as an ensemble of objects rather than pixels. This recent paradigm is increasingly embedded in the fields of image processing, geographic information science, and remote sensing [ 20 – 22 ]. It brings additional elements of analysis related to urban structures of the city. Post-Soviet urban areas like Yakutsk are a mixture of Soviet blocks, post-modern buildings, wooden buildings, and individual houses mostly constructed from wood, where the roofing panels are mostly made of metal, fiber cement, and bitumen. An object-oriented morphometric approach combining the calculation of geometric attributes (e.g., area, elongation, convexity, circularity) for each urban object detected, and morphometric rules enable us to extract object urban sprawl, built-up areas categories, and their associated socioeconomic uses [ 23 , 24 ]. There is a growing interest in morphological image processing due to the increasing availability of high-resolution imagery. In this context, many methods integrating the shape and geometry of the objects composing a natural scene were developed. The use of such operators can be considered following two types of implementation: (1) attributes are integrated in the segmentation procedures using a tree hierarchical representation of the image (e.g., morphological trees), and (2) attributes are calculated over segmented objects. The first implementation requires complementary filtering operations during the tree construction procedure (e.g., using morphological filters). An additional classification step is applied over the filtered map using supervised classifiers [ 25 – 27 ]. The first implementation could be interesting for enhancing conventional land use classification by adding spatial information. Nevertheless, it does not permit a precise characterization of objects, in addition to a higher computational cost. The second implementation is based on three steps, which are segmentation of the input image, geometric attribute calculation over generated objects, and rule construction. It presents a better trade-off for our case study and offers more flexibility and more precise characterization of the objects by computing geometric attributes over segmented objects [ 28 – 30 ].
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Behind "successful" land acquisition : a case study of the Van Quan new urban area project in Hanoi, Vietnam

Behind "successful" land acquisition : a case study of the Van Quan new urban area project in Hanoi, Vietnam

Step 10: If approved, the project owner shall carry out site clearance and compensation plan, paying compensation and allowances, or providing resettlement to the PAPs[r]

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Associations between area-level unemployment, body mass index, and risk factors for cardiovascular disease in an urban area

Associations between area-level unemployment, body mass index, and risk factors for cardiovascular disease in an urban area

work and were available for work and either: (a) had actively looked for paid work in the past four weeks; (b) were on temporary lay-off and expected to return to their job; (c) had definite arrangements to start a new job in four weeks or less.” (Statistics Canada 2007). A 250 m buffer-zone centered on the individual’s place of residence was created, and the census-based unemployment rate within this zone was then geo-linked to the individual. If the buffer-zone fell entirely within a given Census Tract, then the Census unemployment rate corresponded exactly to the buffer-zone rate. If, however, the buffer- zone overlapped 2 or more Census Tracts, then a weighted average of the unemployment rate in each Census Tract which the buffer-zone overlapped was calculated based on the overlap size (Figure 4). The same technique was used to calculate area-level education. Area-level education was operationalised using the proportion of the population 20 years and older with less than grade 9 as their highest level of education (Veugelers et al 2001). Finally, given that neighbourhood effects are likely nonlinear (Granovetter 1978; Sundquist et al 2006), we modeled area-level variables categorically. In order to increase the discriminative ability of our main effect, ALU was operationalised using quartiles. Area-level education was operationalised into categories based on gaps in the variable’s distribution.
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Urban Transformations in the West Bank of Palestine, Drivers and Consequences : a case of Ramallah Area

Urban Transformations in the West Bank of Palestine, Drivers and Consequences : a case of Ramallah Area

Approximately 913.000 donum, 16% of the WB total land between 1979 and 1992. While, 26.7 and 27% of total area of the WB in the Jordan Valley and Jerusalem desert respectively, since the signed of Oslo Accord up today has confiscated. The result of Israeli colonies and Separation Wall through consecutive years that based on false grounds and violated international law infringe Urban Palestinian Development, particularly in the area C that covered about 62% of total area of the WB, which led the Palestinian invested in the urban areas and the main cities that classified area A. Arguably, the disparities of lands endowments due to geopolitical classification according to Oslo Accord and the Separation Wall, caused a high land price in the cities and the possibility of construction becoming complex due to high price of apartment, conversely prohibition in the rural area force them displaced to urban area. However, the Restriction of building, as a result for the first point, the process of civil construction are prohibited in the area C and in Jerusalem. Thus; the Palestinians are forced to construct under their responsibility without permissions in this area, or reside in A and B area and under hard condition in Jerusalem. According to Arij institute 2004, the population density in area A is about 969 Palestinian/km² accused to squeeze on lands, whereas 261 Israeli/ km² , with 2% average growth in ‘Israel’ while 6% in the Colonies of the WB and Jerusalem.
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