965 research outputs found

    Pathogenicity of local Metarhizium anisopliae var. acridum strains on Locusta migratoria migratorioides Reiche and Farmaire and Zonocerus variegatus Linnaeus in Senegal

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    Locusts and grasshoppers are the most important economical threat in the sahelian agricultural system. Principal control strategies of these pests are synthetic chemicals which are, however, harmful to the environment and human health. Metarhizium anisopliae based biopesticide Green Muscle IMI330189 has been recently developed for the control of locusts and grasshoppers. In this paper, we assessed the pathogenicity of three local strains of M. anisopliae var. acridum on Locusta migratoria migratorioides and Zonocerus variegatus, in comparison to the commercial product, IMI330189. There was various level of pathogenicity within the strains on the two pests. On L. migratoria, DPV5 caused the highest mortality after three weeks (91.2%). There was a significant difference between DPV5 and IMI330189. However, there were no significant differences between IMI330189 and the other strains. On Z. variegatus there were no significant differences between IMI330189 DPV5 and DPV10. DPV15 had the lowest pathogenic activity. Moreover, the comparison of susceptibility of both insect pests to Metarhizium strains showed that L. migratoria is more susceptible than Z. variegatus. DPV5 had the shortest LT50 on L. migratoria 7.1 days whereas on Z. variegatus, the LT50 value of DPV5 was comparable to IMI330189. Our study suggests that, DPV5 which was isolated from Kraussaria angulifera in Senegal is a promising candidate for future development for locusts and grasshoppers control in the country.Keywords: Green Muscle, African migratory locust, grasshoppers, local strains, biopesticide

    Osteolipoma: An unusual tumor of the parotid region

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    SummaryPurpose of studyOncology of the parotid region is rich and varied, like its components. During his career, the ENT surgeon may come across such an exceptional tumor as osteolipoma. The aim of this study was to describe the rarity and the etiopathogeny of osteolipoma with parapharyngeal location.Patients and methodWe had the opportunity to find this uncommon tumor in a 21-year-old female patient. The mass located in the parotid region was hard, barely mobile and at first looked like a parotid tumor. Total parotidectomy with facial nerve preservation was performed. It revealed a stony and dented tumor inside the internal lobe of the parotid located in the parapharyngeal space between the vertical portion of the mandible anteriorly and the styloid apophyse posteriorly. Macroscopic examination of the piece evidenced a lipomatous mass with hard as bone nodes in its middle. Histology revealed an osteolipoma.ConclusionA review of the literature shows the uncommon occurrence of this type of tumor. A few rare cases were reported among which two involving the parapharyngeal space

    Non-local corrections to dynamical mean-field theory from the two-particle self-consistent method

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    Theoretical methods that are accurate for both short-distance observables and long-wavelength collective modes are still being developed for the Hubbard model. Here, we benchmark against published diagrammatic quantum Monte Carlo results an approach that combines local observables from dynamical mean-field theory (DMFT) with the two-particle self-consistent theory (TPSC). This method (TPSC+DMFT) is relevant for weak to intermediate interaction, satisfies the local Pauli principle and allows us to compute a spin susceptibility that satisfies the Mermin-Wagner theorem. The DMFT double occupancy determines the spin and charge vertices through local spin and charge sum rules. The TPSC self-energy is also improved by replacing its local part with the local DMFT self-energy. With this method, we find improvements for both spin and charge fluctuations and for the self-energy. We also find that the accuracy check developed for TPSC is a good predictor of deviations from benchmarks. TPSC+DMFT can be used in regimes where quantum Monte Carlo is inaccessible. In addition, this method paves the way to multi-band generalizations of TPSC that could be used in advanced electronic structure codes that include DMFT.Comment: 15 pages, 19 figures. Changes from v1: added reference

    Plasmodium falciparum malaria co-infection with tick-borne relapsing fever in Dakar

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    Abstract Background West African tick-borne relapsing fever (TBRF) due to Borrelia crocidurae and malaria are co-endemics in Senegal. Although expected to be high, co-infections are rarely reported. A case of falciparum malaria and B. crocidurae co-infection in a patient from Velingara (South of Senegal) is discussed. Case A 28\ua0year-old-male patient presented to Aristide Le Dantec Hospital for recurrent fever. He initially presented to a local post health of Pikine (sub-urban of Dakar) and was diagnosed for malaria on the basis of positive malaria rapid diagnostic test (RDT) specific to Plamodium falciparum . The patient was treated as uncomplicated falciparum malaria. Four days after admission the patient was referred to Le Dantec Hospital. He presented with fever (39\ua0\ub0C), soreness, headache and vomiting. The blood pressure was 120/80\ua0mmHg. The rest of the examination was normal. A thick film from peripheral blood was performed and addressed to the parasitology laboratory of the hospital. Thick film was stained with 10% Giemsa. Trophozoite of P. falciparum was identified at parasite density of 47 parasites per microlitre. The presence of Borrelia was also observed, concluding to malaria co-infection with borreliosis. Conclusions Signs of malaria can overlap with signs of borreliosis leading to the misdiagnosis of the latter. Thick and thin smear or QBC test or molecular method may be helpful to detect both Plamodium species and Borrelia . In addition, there is a real need to consider co-infections with other endemics pathogens when diagnosing malaria

    Spin Hall conductivity in the Kane-Mele-Hubbard model at finite temperature

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    The Kane-Mele model is known to show a quantized spin Hall conductivity at zero temperature. Including Hubbard interactions at each site leads to a quantum phase transition to an XY antiferromagnet at sufficiently high interaction strength. Here, we use the two-particle self-consistent approach (TPSC), which we extend to include spin-orbit coupling, to investigate the Kane-Mele-Hubbard model at finite temperature and half-filling. TPSC is a weak to intermediate coupling approach capable of calculating a frequency- and momentum-dependent self-energy from spin and charge fluctuations. We present results for the spin Hall conductivity and correlation lengths for antiferromagnetic spin fluctuations for different values of temperature, spin-orbit coupling and Hubbard interaction. The vertex corrections, which here are analogues of Maki-Thompson contributions, show a strong momentum dependence and give a large contribution in the vicinity of the phase transition at all temperatures. Their inclusion is necessary to observe the quantization of the spin Hall conductivity for the interacting system in the zero temperature limit. At finite temperature, increasing the Hubbard interaction leads to a decrease of the spin Hall conductivity. This decrease can be explained by band-gap renormalization from scattering of electrons on antiferromagnetic spin fluctuations.Comment: 11 pages, 8 figure

    An Improved Two-Particle Self-Consistent Approach

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    The two-particle self-consistent approach (TPSC) is a method for the one-band Hubbard model that can be both numerically efficient and reliable. However, TPSC fails to yield physical results deep in the renormalized classical regime of the bidimensional Hubbard model where the spin correlation length becomes exponentially large. We address the limitations of TPSC with improved approaches that we call TPSC+ and TPSC+SFM. In this work, we show that these improved methods satisfy the Mermin-Wagner theorem and the Pauli principle. We also show that they are valid in the renormalized classical regime of the 2D Hubbard model, where they recover a generalized Stoner criterion at zero temperature in the antiferromagnetic phase. We discuss some limitations of the TPSC+ approach with regards to the violation of the f-sum rule and conservation laws, which are solved within the TPSC+SFM framework. Finally, we benchmark the TPSC+ and TPSC+SFM approaches for the one-band Hubbard model in two dimensions and show how they have an overall better agreement with available diagrammatic Monte Carlo results than the original TPSC approach

    Anévrismes de l’aorte abdominale sous-rénale rompus: aspects chirurgicaux à Dakar: à propos de 6 observations

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    La rupture des anévrismes de l'aorte est une situation catastrophique. La chirurgie ouverte et le traitement endovasculaire sont débattus comme option. Dans cette étude sont évaluées les modalités du traitement chirurgical et ses résultats sur 6 malades opérés pour rupture d'un anévrysme de l'aorte abdominale sous-rénale. Dans 4 cas, il s'agissait d'une « rupture contenue » dans le péritoine pariétal postérieur, avec un hématome péri vertébral. Dans les 2 autres cas, il s'agissait d'une rupture en péritoine libre. Tous les malades avaient bénéficié après contrôle de l'hémostase d'une mise à plat de l'anévrisme suivie de greffe d'une prothèse aortique. Des complications précoces étaient notées chez 2 patients à type d'insuffisance rénale aigue et de poussée hypertensive. La mortalité opératoire était de 16,66%. La morbi-motalité des anévrismes rompus de l'aorte abdominale est particulièrement élevée, d'où la nécessité d'un dépistage précoce des patients à risque et l'introduction de la chirurgie endovasculaire

    The endogenous subcellular localisations of the long chain fatty acid-activating enzymes ACSL3 and ACSL4 in sarcoma and breast cancer cells

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    Fatty acid uptake and metabolism are often dysregulated in cancer cells. Fatty acid activation is a critical step that allows these biomolecules to enter cellular metabolic pathways such as mitochondrial β-oxidation for ATP generation or the lipogenic routes that generate bioactive lipids such as the inositol phospholipids. Fatty acid activation by the addition of coenzyme A is catalysed by a family of enzymes called the acyl CoA synthetase ligases (ACSL). Furthermore, enhanced expression of particular ACSL isoforms, such as ACSL4, is a feature of some more aggressive cancers and may contribute to the oncogenic phenotype. This study focuses on ACSL3 and ACSL4, closely related structural homologues that preferentially activate palmitate and arachidonate fatty acids, respectively. In this study, immunohistochemical screening of multiple soft tissue tumour arrays revealed that ACSL3 and ACSL4 were highly, but differentially, expressed in a subset of leiomyosarcomas, fibrosarcomas and rhabdomyosarcomas, with consistent cytoplasmic and granular stainings of tumour cells. The intracellular localisations of endogenously expressed ACSL3 and ACSL4 were further investigated by detailed subcellular fractionation analyses of HT1080 fibrosarcoma and MCF-7 breast cancer cells. ACSL3 distribution closely overlapped with proteins involved in trafficking from the trans-Golgi network and endosomes. In contrast, the ACSL4 localisation pattern more closely followed that of calnexin which is an endoplasmic reticulum resident chaperone. Confocal immunofluorescence imaging of MCF-7 cells confirmed the intracellular localisations of both enzymes. These observations reveal new information regarding the compartmentation of fatty acid metabolism in cancer cells
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