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A thrips vector of tomato spotted wilt virus responds to tomato acylsugar chemical diversity with reduced oviposition and virus inoculation.
There is increasing evidence that acylsugars deter insect pests and plant virus vectors, including the western flower thrips (WFT), Frankliniella occidentalis (Pergande), vector of tomato spotted wilt virus (TSWV). Acylsugars are sugar-polyesters composed of saturated, un-saturated, and variously branched short and long chain fatty acids (FAs) esterified to a glucose (acylglucose) or sucrose (acylsucrose) moiety. We sought to understand how acylsucrose amount and composition of associated FA profiles interacted to mediate resistance to WFT oviposition and TSWV inoculation on tomato leaves. Towards this goal, we examined WFT oviposition and TSWV inoculation behavior on tomato lines bred to exude varying amounts of acylsucrose in association with diverse FA profiles. Our data show that as acylsucrose amounts increased, WFT egg-laying (oviposition) decreased and TSWV inoculation was suppressed. Western flower thrips also responded to FA profiles that included iC4, iC11, nC12 and nC10 FA. These findings support improving acylsugar-mediated resistance against WFT by breeding tomatoes exuding greater amounts of acylsucrose associated with specific FA profiles. We show that increasing acylsucrose amount output by type IV trichomes and selecting for particular FA profiles through advanced breeding profoundly affects WFT behavior in ways that benefit management of WFT as direct pests and as TSWV vectors
Fermat-linked relations for the Boubaker polynomial sequences via Riordan matrices analysis
The Boubaker polynomials are investigated in this paper. Using Riordan
matrices analysis, a sequence of relations outlining the relations with
Chebyshev and Fermat polynomials have been obtained. The obtained expressions
are a meaningful supply to recent applied physics studies using the Boubaker
polynomials expansion scheme (BPES).Comment: 12 pages, LaTe
Kaposi sarcoma in an HIV-negative Tunisian patient: A rare cause of metatarsalgia
AbstractBackgroundKaposi sarcoma (KS) is an angioproliferative neoplasm that is commonly associated with human herpes virus-8 (HHV-8) and human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). KS with osseous involvement is a rare occurrence, and is far more common in acquired immunodeficiency syndrome (AIDS)-related KS.Case presentationWe present a 32-year-old Tunisian man, HIV negative, who presented with a 4-year history of atraumatic mechanical metatarsalgia that progressively worsened with a limping gait. Physical examination revealed marked symmetrical forefoot lymphedema and a painful restricted left knee joint movement. Physical examination showed purple-blue plaques and nodules on the feet and ankles. Serologic tests for HIV and syphilis were negative. Plain radiography of the feet revealed numerous small lytic lesions. There were also scattered lytic lesions in the metaphysis of the proximal tibia and fibula. Osteolysis was predominantly left. Magnetic resonance imaging of the feet showed abnormal bone marrow signal of metatarsals and phalanges. Skin lesion biopsy yielded the diagnosis of Kaposi sarcoma. The disease was managed with chemotherapy including vinblastine.ConclusionIn a patient presenting with metatarsalgia without a commonly detected cause, it is mandatory to search for other lesions that may point to a rare diagnosis as KS which is famous for involvement of the metatarsal bone
Addition-Deletion Networks
We study structural properties of growing networks where both addition and
deletion of nodes are possible. Our model network evolves via two independent
processes. With rate r, a node is added to the system and this node links to a
randomly selected existing node. With rate 1, a randomly selected node is
deleted, and its parent node inherits the links of its immediate descendants.
We show that the in-component size distribution decays algebraically, c_k ~
k^{-beta}, as k-->infty. The exponent beta=2+1/(r-1) varies continuously with
the addition rate r. Structural properties of the network including the height
distribution, the diameter of the network, the average distance between two
nodes, and the fraction of dangling nodes are also obtained analytically.
Interestingly, the deletion process leads to a giant hub, a single node with a
macroscopic degree whereas all other nodes have a microscopic degree.Comment: 8 pages, 5 figure
Tumeur Germinale De L\'espace Para Pharynge : A Propos D\'un Cas
Les tumeurs germinales à localisation cervico-faciale sont rares. Nous rapportons l\'observation d\'une une fillette de 7 ans porteuse d\'une tumeur maligne à cellules germinales de l\'espace para-pharyngé droit traité par chimiothérapie. Les particularités
étiopathogéniques, thérapeutiques, et pronostiques de cette tumeur sont rappelées après une revue des données de la littérature.Extragonadal germ cell tumors of the head and neck are very rare. We report the case of a 7-year-old girl with malignant
germ cell tumor of the right parapharyngeal space treated by chemotherapy. Etiopathogenic, therapeutic, and prognostic characteristics of this tumour are recalled after a review of the literature data. Keywords: Extragonadal germ cell tumors, parapharyngeal tumors. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 18 2007: pp. 61-6
Myxome Du Maxillaire A Propos D\'un Cas
Les myxomes des maxillaires sont des tumeurs bénignes rares dont la pathogénie reste encore controversée. Leur indolence et la pauvreté des manifestations qui les accompagnent rendent leur diagnostic souvent tardif et leur prise en charge difficile. Nous présentons un cas de myxome du maxillaire chez un nourrisson âgé de 12 mois suivi d\'une revue de la littérature permettant de synthétiser les données cliniques ainsi que la stratégie thérapeutique à adopter.Maxillary myxoma are rare benign tumours whose pathogenesis remains extremely discussed. The poor clinical picture and the absence of pain makes the diagnosis difficult. We report a pediatric case of maxillary myxoma of a 12- monthold infant and review the clinical features, radiographic evaluation and the appropriate treatment Keywords:Myxoma - maxillary - benign tumor. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 18 2007: pp. 43-4
Cholesteatome Congenital De L’oreille Moyenne A Propos De Deux Cas
But :Le cholesteatome congenital de l’oreille moyenne est une entite rare. L’objectif de ce travail est de discuter les particularites cliniques et therapeutiques de cette pathologie a travers deux observations de malades presentant un cholesteatome congenital operes et suivis au service d’ORL et de chirurgie cervico-faciale Fattouma Bourguiba Monastir, entre 2002 et 2008. Résultats : Il s’agissait de deux garcons, ages de 5 et 7 ans. La symptomatologie etait dominee par l’apparition d’une hypoacousie et l’examen otologique a revele un tympan complet dans les deux cas. La TDM des rochers a permis d’evoquer le diagnostic du cholesteatome congenital et d’apprecier les extensions locales des lesions. Les deux malades ont eu une tympanoplastie en technique fermee. Conclusion : L’evolution du cholesteatome congenital est insidieuse et le diagnostic est souvent tardif. Le traitement est chirurgical, domine par la tympanoplastie en technique fermee. Mots clès : Chlolesteatome congenital, hypoacousie, tympan complet, tympanoplastie en technique fermee, technique ouverte
Understanding Search Trees via Statistical Physics
We study the random m-ary search tree model (where m stands for the number of
branches of a search tree), an important problem for data storage in computer
science, using a variety of statistical physics techniques that allow us to
obtain exact asymptotic results. In particular, we show that the probability
distributions of extreme observables associated with a random search tree such
as the height and the balanced height of a tree have a traveling front
structure. In addition, the variance of the number of nodes needed to store a
data string of a given size N is shown to undergo a striking phase transition
at a critical value of the branching ratio m_c=26. We identify the mechanism of
this phase transition, show that it is generic and occurs in various other
problems as well. New results are obtained when each element of the data string
is a D-dimensional vector. We show that this problem also has a phase
transition at a critical dimension, D_c= \pi/\sin^{-1}(1/\sqrt{8})=8.69363...Comment: 11 pages, 8 .eps figures included. Invited contribution to
STATPHYS-22 held at Bangalore (India) in July 2004. To appear in the
proceedings of STATPHYS-2
Spondylodiscite tuberculeuse : 12 ans d'expérience dans un centre hospitalier en Tunisie
Objectifs : Décrire les particularités épidémiologiques, cliniques et paracliniques des spondylodiscites
tuberculeuses et déterminer les facteurs prédictifs d’une évolution défavorable.
Patients et Méthode: Etude rétrospective sur une période de 12 ans. Le diagnostic a été porté sur des
preuves bactériologiques, anatomopathologiques ou sur un faisceau d’arguments.
Résultats : Il s’agissait de 49 patients (26F/23H), âgés en moyenne de 51,84 ans. Le délai moyen de
diagnostic était de 6,65 mois. Un facteur prédisposant à l’infection a été relevé chez 38,7% des
patients. L’étage lombaire était le plus touché (67,3%). L’imagerie par résonnance magnétique était
pathologique dans tous les cas où elle a été effectuée. Le diagnostic de certitude a été porté dans 9 cas
sur une preuve histologique. La ponction biopsie disco-vertébrale a permis de confirmer le diagnostic
dans 6/36 cas. Tous les patients ont reçu un traitement anti-tuberculeux d’une durée moyenne de 13,59
mois associé à un geste interventionnel dans 8 cas. L’évolution était favorable dans 84,2% des cas.
Nous avons identifiés quatre facteurs prédictifs d’une évolution défavorable: une hyperleucocytose
initiale ≥11500 éléments/mm3
(p=0,031), la présence d’abcès ou de collection à l’imagerie (p=0,018);
un tassement vertébral à l’IRM (p=0,018) et l’existence de déformation osseuse avant correction
chirurgicale (p<0,001).
Conclusion: La spondylodiscite tuberculeuse devrait être suspectée devant toute rachialgie
inflammatoire. Une prise en charge précoce est la clé pour éviter les complications neurologiques et
ostéo-articulaires
Research Output on Strategy Formulation and Implementation: Global Picture, Development and Key Bibliometric Indicators
Effective strategic management serves as the bedrock for an organization's vision, goal attainment, and stakeholder expectations. Consequently, the research focus on strategy formulation and implementation has garnered substantial attention in recent decades. This study aims to evaluate bibliometric indicators of research productivity related to strategy formulation and implementation through meticulous bibliometric analysis. The analysis leverages the R Bibliometrix library on scientific publications indexed in the Web of Science database. The dataset comprises 672 publications on strategy formulation and implementation, spanning the years 1971 to 2022. Authored by 1,280 contributors from 69 countries, these publications are dispersed across 374 diverse sources, including journals and books. Impressively, this body of work has garnered a cumulative total of 24,635 citations, averaging 36.66 citations per document. The top-ranking article, "The Resource-Based Theory of Competitive Advantage: Implications for Strategy Formulation" by Robert M. Grant, stands out with 3,649 citations. Examining global scientific production, the United States emerges as the primary contributor with 154 publications (22.91%), followed by China with 56 (8.33%) and the United Kingdom with 54 (8.03%).
The study's findings offer valuable insights for researchers and organizations alike, shedding light on significant research contributions. This comprehensive assessment enables a nuanced understanding of the historical progression and growth within this domain. Additionally, it identifies current focal points of research and highlights areas that warrant attention in future studies
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