423 research outputs found

    Global existence and asymptotic behavior for a nonlinear degenerate SIS model

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    In this paper we investigate the global existence and asymptotic behavior of a reaction diffusion system with degenerate diffusion arising in the modeling and the spatial spread of an epidemic disease

    Pesticide, politics and a paradise lost: toxicity, slow violence and survival environmentalism in Ambikasutan Mangad’s "Swarga"

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    Ambikasutan Mangad’s “Enmakaje” (translated into English as “Swarga” by J. Devika) is a dystopic tale of socio-environmental crisis that represents the actual event of endosulfan disaster in the Indian state of Kerala in literary imagination. This paper examines how Mangad’s text represents the “slow violence” the endosulfan disaster unleashes, in encrypted and incremental ways, upon the environs, bodies and psyches of the victims. It looks into how the politics of denial tries to suppress the inconvenient truth about the invisible invasion of the foreign element in an area where the local people live in reciprocity with their immediate environment. The paper also dissects how Mangad’s use of the images of deformed human bodies with congenital anomalies in rendering the amorphous threats visible brings the environmental and disability concerns together and how these contravened and disabled bodies mark the uncanny nature of the disaster. Finally, it focuses on how the poor victims put up a collective protest in the form of an ecopopulist movement against the pesticide lobby and how their resistance to the socio-environmental injustice substantiates the fact that in a postcolonial country like India environmental issues are integrally connected to the issues of sustenance, shelter and survival of the “ecosystem people”.“Enmakaje” de Ambikasutan Mangad (traducido al inglés por J. Devika como “Swarga”) es una historia distópica de crisis socioambiental que representa el evento real del desastre del endosulfán en el estado indio de Kerala en la imaginación literaria. Este artículo examina cómo el texto de Mangad representa la “violencia lenta” que desata el desastre del endosulfán, de forma encriptada y progresiva, sobre el entorno, los cuerpos y la psique de las víctimas. Analiza cómo la política de la negación intenta suprimir la verdad incómoda sobre la invasión invisible del elemento extranjero en un área donde la gente local vive en reciprocidad con su entorno inmediato. El documento también analiza cómo el uso que hace Mangad de las imágenes de cuerpos humanos deformados con anomalías congénitas para hacer visibles las amenazas amorfas une las preocupaciones ambientales y de discapacidad y cómo estos cuerpos contravenidos y discapacitados marcan la naturaleza misteriosa del desastre. Finalmente, se centra en cómo las víctimas pobres organizan una protesta colectiva en forma de movimiento ecopopulista contra el lobby de los pesticidas y cómo su resistencia a la injusticia socioambiental corrobora el hecho de que, en un país poscolonial como la India, los problemas ambientales están integralmente conectados. a los temas de sustento, cobijo y sobrevivencia de la “gente del ecosistema”

    Image Compression Based On Region Of Interest For Computerized Tomography Images

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    The use of computers for handling image data in the healthcare is growing. The amount of data produced by modem image generating techniques, such as Computed Tomography (CT) and Magnetic Resonance (MR), is vast. The amount of data might be a problem from a storage point of view or when the data is sent over a network. To overcome these problems data compression techniques adapted to these applications are needed. Many classes of images contain some spatial regions which are more important than other regions. Compression methods which are capable of achieving higher reconstruction quality of important parts of the image have been implemented. For medical images, only a small portion of the image might be diagnostically useful, but the cost of wrong interpretation is high. Algorithms which deliver lossless compression within the regions of interest (ROI), and lossy compression elsewhere in the image, might be the key to providing efficient and accurate image coding to the medical community. In this thesis both of compression techniques (lossy and lossless) of medical images using the JPEG algorithm (DCT), will be discussed

    Changes in Somatic Cell Count, Composition and Cytokine Levels in Milk from Cows with Mastitis Due to Mixed Infections

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    Background: Mastitis is a mammary gland inflammation that is very common worldwide, mostly caused by bacteria, and causes enormous economic losses. Many microorganisms cause this disease. The most common causes of mastitis by these microorganisms are Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Streptococcus agalactiae (S. agalactiae). The anti-inflammatory properties of transforming growth factor (TGF)-β include: 1) limiting interferon (IFN)-γ production; 2) increasing the expression of the ınterleukine (IL)-1 receptor antagonist; 3) inhibiting macrophage production of chemokines, pro-inflammatory cytokines, nitric oxide, and reactive oxygen intermediates; and 4) increasing macrophage clearance of bacterial debris and damaged parenchymal cells. It is stated that cytokines and milk composition change in case of mastitis. In this study, it was aimed to reveal the changes in milk TGF-β1 and Tumor necrosis factor (TNF)-α concentrations and milk composition in mixed infections caused by three pathogens causing mastitis.Materials, Methods & Results: In this study, milk samples from 90 cows were divided into 5 groups. Tumor necrosis factor (TNF)-α and TGF-β1 concentrations and milk composition were determined in these milk samples. The California Mastitis Test (CMT) was applied to the cows included in the study and scoring was done. According to the CMT results of the milk samples taken, CMT(-) cows were included in group 1 (n = 22). Those with the CMT(+) were taken to the microbiology laboratory for analysis within 2 h. After the bacteria was determined, combination groupings were formed. Group 2 (n = 17) with S. aureus and E. coli, group 3 (n = 21), S. agalactiae with S. aureus, S. agalactiae and E. coli together, group 4 (n = 8) and CMT (+) but no bacterial growth formed group 5 (n = 22).Somatic cell counts were made in the milk samples taken from the cows belonging to the groupings. Somatic cell count was measured with the DeLaval Cell Counter® (Cell Counter DCC) device. Mineral matter, fat, protein, lactose, electrical conductivity and specific gravity were measured in milk samples using Lactoscan Milk Analyzer (Milkotronic/EUROPE). Milk samples were then stored at -80°C to measure TGF-β1 and TNF-α. Tumor necrosis factor-α and TGF-β1 concentrations in milk samples were measured using ELISA kits (Sunred Biological Technology).Discussion: Changes in milk TNF-α and TGF-β1 concentration and milk composition were determined in milk samples with mastitis caused by mixed infection. The TNF-α concentration of group 4 was higher than the other groups. On the other hand, the highest concentration of TGF-β1 was found in group 2. While the number of somatic cells in group 1 was lower than in groups 2, 3, and 4, there was no statistical difference between groups 1 and 5. The lowest milk fat ratio was found in group 1, and it was found to be statistically lower than groups 2, 3, and 4. While the rate of solid-non-fat of group 1 increased compared to groups 2 and 3, the highest protein ratio was found in groups 1 and 5. There was no difference between the 5 groups in terms of mineral matter ratios. While the specific gravity was highest in group 1, there was no statistical difference between the other 4 groups. Overall, it was concluded that there was an increase in TNF-α and TGF-β1 concentrations and a change in milk composition in samples with bacterial growth.Keywords: bovine mastitis, cytokine, milk composition, raw milk, transforming growth factor

    Molecular structure, vibrational spectroscopic and HOMO/LUMO studies of some organotellurium compounds by quantum chemical investigations

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    Quantum mechanical calculations of geometries, energies and vibrational frequencies of organic mercury and tellurium compounds containing azomethine group, molecules a1-a5 and containing azo group, molecules a6-a10 have been undertaken using density functional theory. The optimized geometrical parameters such as bond lengths, bond angles and dihedral angles showed that only organomercuric compounds have planer structures. The calculation of the total energy and HOMO-LUMO energy gap were showed that organotellurium compounds have higher reactivity than the corresponding organomercuric compounds. As well it showed the HOMO orbitals are localized mainly on tellurium, nitrogen and bromine atoms moieties, while the LUMO of π nature are mostly located on the phenyl ring. The calculated vibrational frequencies of molecules a1 and a7 are in good agreement with experimental frequencies with correlation coefficient r2 value is 0.9875 and 0.9987, respectively

    Quantification du transport solide par la technique floue, application au barrage de Beni Amrane (Algérie)

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    L’Algérie, caractérisée par un climat semi-aride, est menacée par l’érosion des terres agricoles qui provoque l’augmentation du transport solide et l’envasement croissant des barrages. Cet article décrit une nouvelle méthode d’estimation des flux de matières en suspension (MES) au niveau d’un barrage algérien (barrage de Beni Amrane) basée sur la logique floue. Cette dernière utilise des termes flous tels que « faible », « moyen » et « élevé », pour décomposer le processus débit-MES en plusieurs sous-ensembles flous et d’en déduire les quantités de matières solides en fonction du débit observé de la rivière. Les performances de cette méthode ont été évaluées en période de calage, mais aussi en période de validation, pour mieux juger de la capacité prédictive du modèle à ces deux échelles. En comparant la logique floue avec un modèle empirique régressif utilisant une relation de puissance, nous avons démontré la robustesse du modèle flou en tant qu’outil de quantification du transport solide.Sediment transport and erosion is a complex natural process that is strongly influenced by human activities such as deforestation, agriculture and urbanization. In particular, suspended sediments play a key role in controlling water quality and they can cause a major reduction in the capacity of a stream for handling floods. In Algeria, increasing erosion and suspended loads are responsible for serious problems in agricultural land and hydraulic reservoirs, since the suspended load and its sedimentation lead to flooding and dam silting. Water and soil conservation practices, such as contour ridges and areas of reforestation, were introduced in many regions of Algeria in order to decrease erosion and to collect runoff in hill-slope catchments.Relationships for water discharge and suspended sediment load can be divided into three types: empirical models that allow quantification of erosion on annual time scales, such as the Wischmeier and Smith soil loss equation; conceptual models, which include several reservoirs estimating sediment load on different time scales; and finally, physically-based models, which introduce physical laws such as the Saint-Venant equation. These models represent another category, and allow the estimation of sediment load in different areas of the watershed and supply spatial results. These models also take into account numerous variables that are difficult to obtain on a regional scale.The objective of this research was to develop runoff-suspended sediment models for the Beni Amrane reservoir. This reservoir is located in the Isser watershed, situated in northern Algeria. This basin covers an area of 4,000 km2 and is characterized by a semi-arid climate and a very high soil erosion rate, exceeding 2,000 tons/km2/year. The Beni Amrane reservoir represents an important dam as it supplies the Keddara dam, which in turn supplies the town of Algiers with drinking water.In the present study, two approaches to suspended sediment simulation were applied on hourly time scales for suspended sediment concentrations, and on daily time scales for water discharge and solid discharge analysis. The first approach is an empirical regression model based on a rating curve and uses a relationship between the observed runoff and the sediment concentration values. The model uses only two parameters, with the second being based on fuzzy logic. Fuzzy logic is already used in many scientific domains, and represents a new simulation technique based on artificial intelligence. Fuzzy variables were used to organize knowledge that is expressed ‘linguistically’ into a formal analysis (for example ‘high suspended sediment’, ‘average suspended sediment’ and ‘low suspended sediment’). The simulation results confirm the performances and robustness of the fuzzy logic model for the two time scales. In fact, the Nash criterion, which is the principal validation criterion for the models, displayed high performances in calibration and validation periods. The neurofuzzy model (fuzzy logic with neural supervised learning) offers a simulation advantage. On an hourly time scale, while increasing the number of fuzzy rules, the model results in good precision with the observed suspended sediments.The fuzzy logic model results showed that the Nash criterion for two periods (calibration and validation) was greater than 88%, and the peaks of suspended sediments were generally correctly reproduced for the four episodes studied. This is in contrast to the empirical model, where the Nash efficiency was generally weak and decreased during the validation period. In this latter period, the Nash criterion was often negative, the global error was high and the maximum concentration peak was underestimated.On a daily time scale, knowing the complexity of the runoff-suspended sediment process, we have analyzed these two models for solid discharge simulation. The study was carried out on daily solid discharge data collected from the gauging station on the Isser River (1986 to 1989). While based on the same validation criteria, i.e. the Nash efficiency and the global error, the fuzzy logic model appeared more robust than the empirical model. The fuzzy logic model produced better estimates of the daily sediment yield than the empirical model during calibration and validation periods, and it represents a high prediction power. Thus, we have validated the fuzzy logic model as a tool for simulation of runoff of suspended sediments, and it can be explored to predict sediment loading and silting in Algerian reservoirs

    Evaluation of Optical Model Potential using Neutron Induced Cross Section Reactions for Spherical Uranium-235 Isotope up to 20MeV

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    The evaluation is based mainly on the calculations of the nuclear optical model potential and the relevant parameters are collected and selected from References Input Parameter Library (RIPL) which is being developed under the international project coordinated by the International Atomic Energy Agency (IAEA).  The analyzing of a complete energy range has been done starting from threshold energy for each reaction.  The cross sections are reproduced in fine steps of incident neutron energy with 0.01MeV intervals with their corresponding errors.   The recommended cross sections for available experimental data taken from EXFOR library have been calculated for all the considered neutron induced reactions for U-235 isotope.  The calculated results are analyzed and compared with the experimental data.  The optimized optical potential model parameters give a very good agreement with the experimental data over the energy range 0.001-20MeV for neutron induced cross section reactions (n,f), (n,tot), (n,el), (n,inl), (n,2n), (n,3n), and (n,γ)  for spherical U-235 target element. Keywords: EXFOR nuclear data, induced neutron reactions, 20MeV, recommended cross section, optical model potential

    Extensive primary retroperitoneal fibrosis (Ormond’s disease) with common bile duct and ureteral obstruction: A rare case report

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    AbstractIntroductionIdiopathic retroperitoneal fibrosis (Ormond’s disease) may involve the perirenal tissue, mesentery and biliary system in extremely uncommon situations in addition to classical compression of retroperitoneal structures particularly the ureters.Presentation of caseWe report the case of a 60 year’s old man with clinical manifestation of obstructive jaundice, due to the common bile duct narrowing caused by a primary retroperitoneal fibrosis. Magnetic resonance cholangiopancreatography (MRCP) showed the presence of intrahepatic bile duct obstruction, suggesting the diagnosis of a hilar cholangiocarcinoma. Endoscopic retrograde cholangiopancreatography (ERCP) showed strictures in the proximal common bile duct. A biliary endoprosthesis was inserted at ERCP. Histological investigations as well as CT-scan were compatible with retroperitoneal fibrosis.DiscussionThe main clinical presentation of the Ormond’s disease is compression of the ureters, and less commonly blood vessels and nerves. Our patient presented with obstructive jaundice, due to the common bile duct (CBD) compression, which was unusual. The first description of the extrahepatic biliary obstruction secondary to retroperitoneal fibrosis was made in 1964 and since then only 13 cases have been reported in the medical literature.ConclusionRetroperitoneal fibrosis can cause compression of the CBD and therefore mimic a cholangiocarcinoma. Patients can be successfully managed with long-term CBD stent placement
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