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La kératite fongique est une maladie rare en France, mais potentiellement grave. Nous avons cherché à décrire l’épidémiologie des kératites fongiques à l’île de la Réunion.

Abstract: Einstein's second postulate (light-speed constancy) is modified in the following manner:(1) as to motion of light emitters, no modification is made;(2) as to motion of light absorbers, if the absorber moves with velocityv with respect to the observer, that observer will attribute to light the velocity (c+v). It is shown, with reference to the original Einstein train example, that such a modification of the second postulate restores to kinematics a concept of distant simultaneity. Thus is indicated the complicated (acausal) behavior that must be attributed to light in order that the simple behavior earlier attributed (1) to matter (nonoccurrence of the Lorentz contraction) may be consistent with all known facts. A reply is made to Grøn's critique (2) of the earlier paper on metric standards. It is concluded that further experimental data are needed to decide the simple-light-complicated-matter versus complicated-light-simple-matter issue.

Abstract: In preceding parts of this paper the possibility was examined of accomplishing the entirety of physical description by means of mechanics, without help from field-theoretical ideas. Apart from some easily obtained qualitative agreements with general descriptive features of nuclei and elementary particles, we were balked in this program by an inability to handle in purely mechanical terms the relativistic many-body problem. The present paper is addressed directly to the latter problem. No quantitative calculations are attempted, but three suggestions are made — each of a quite radical nature — concerning the reformulation that will be necessary to restore mechanics to the mainstream of physics.

Abstract: The Ehrenfest paradox is reviewed in order to categorize classes of ldquoresolutionrdquo that are logically at least semiconsistent. Cantoni's candidate is analyzed with reference to such a taxonomy of resolutions.

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Abstract: In this, the first of a two-part paper, a conceptual purification of physics is advocated, whereby the idea of the field is completely eliminated in favor of particulate dynamical laws. Previous work concerning a specific formulation of such purely mechanical laws is reviewed and is shown to imply the possibility of existence of electrons and positrons within nuclei or ldquoelementaryrdquo particles in stable bound states characterized by real mass-energy and imaginary momentum. The second part of the paper will examine the qualitative implications and the sufficiency of such concepts for physical description.Newton, Introduction to thePrincipia

Abstract: Accepted quantum description is stochastic, yet history is nonstochastic, i.e., not representable by a probability distribution. Therefore ordinary quantum mechanics is unsuited to describe history. This is a limitation of the accepted quantum theory, rather than a failing of mechanics in general. To remove the limitation, it would be desirable to find a form of quantum mechanics that describes the future stochastically and the past nonstochastically. For this purpose it proves sufficient to introduce into quantum mechanics, by means of a perfected formal correspondence, certain analogs of the classical initial-condition constants. Through the restoration of such parameters at the quantum level one accomplishes a natural accommodation of time anisotropy, wave-function reduction, and ldquoeventrdquo description by quantum mechanical equations of motion alone, without the need for extra postulates (e.g., a projection postulate). This requires a complete restructuring of quantum measurement theory.

Monocytes were maintained in tissue culture for greater than 3 mo in media supplemented with rCSF-1. These cultures provided susceptible target cells for isolation and propagation of virus from PBMC of HIV-infected patients. HIV isolated into monocytes readily infected other rCSF-1-treated monocytes but only inefficiently infected PHA-stimulated lymphoblasts. Similarly, laboratory HIV strains passaged in T cell lines or virus isolated from patients' leukocytes into PHA-stimulated lymphoblasts inefficiently infected rCSF-1-treated monocytes. Persistent, low-level virion production was detected in macrophage culture fluids by reverse transcriptase activity or HIV antigen capture through 6-7 wk. Marked changes in cell morphology with cell death, syncytia, and giant cell formation were observed in monocyte cultures 2 wk after infection, but at 4-6 wk, all cells appeared morphologically normal. However, the frequency of infected cells in these cultures at 6 wk was 60-90% as quantified by in situ hybridization with HIV RNA probes or by immunofluorescence with AIDS patients' sera. Ultrastructural analysis by EM also showed a high frequency of infected cells; virtually all HIV budded into and accumulated within cytoplasmic vacuoles and virus particles were only infrequently associated with the plasma membrane. Retention of virus within macrophages and the macrophage tropism of HIV variants may explain mechanisms of both virus persistence and dissemination during disease.

Recombinant human colony-stimulating factor-1-treated human peripheral blood-derived monocytes-macrophages are efficient host cells for recovery of the human immunodeficiency virus (HIV) from blood leukocytes of patients with acquired immunodeficiency syndrome. These cells can be maintained as viable monolayers for intervals exceeding 3 months. Infection with HIV resulted in virus-induced cytopathic effects, accompanied by relatively high levels of released progeny virus, followed by a prolonged low-level release of virus from morphologically normal cells. In both acutely and chronically infected monocytes, viral particles were seen budding into and accumulating within cytoplasmic vacuoles. The number of intravacuolar virions far exceeded those associated with the plasma membrane, especially in the chronic phase, and were concentrated in the perinuclear Golgi zone. In many instances, the vacuoles were identified as Golgi elements. Fusion of virus-laden vacuoles with primary lysosomes were rare. The pattern of cytoplasmic assembly of virus was observed with both HIV types 1 and 2 and in brain macrophages of an individual with acquired immunodeficiency syndrome encephalopathy. Immunoglobulin-coated gold beads added to acutely infected cultures were segregated from the vacuoles containing virus; relatively few beads and viral particles colocalized. The assembly of HIV virions within vacuoles of macrophages is in contrast to the exclusive surface assembly of HIV by T lymphocytes. Intracytoplasmic virus hidden from immune surveillance in monocytes-macrophages may explain, in part, the persistence of HIV in the infected human host.

An enzyme-linked immunosorbent assay (ELISA) is described for Pseudomonas aeruginosa exotoxin A. A double antibody sandwich method was used, employing polyvinyl microtiter plates as the solid phase, a primary coat of monospecific rabbit antitoxin serum, an outer layer composed of a horseradish peroxidase-sheep antitoxin immunoglobulin G conjugate, and an ortho-phenylene-diamine substrate. Absorbance (optical density) of hydrolyzed end product was read spectrophotometrically at 492 nm. ELISA detected as little as 30 pg (0.3 ng/ml) of purified toxin, and absorbance was linear over a 20-fold or greater concentration range. Toxin was demonstrated in culture filtrates from 42 of 48 (88%) consecutive clinical P. aeruginosa isolates compared with 37 of 48 (77%) positive by hemagglutination inhibition. Results of the two assays correlated closely (r = 0.82, P less than 0.001). Specificity was confirmed by neutralizability of ELISA activity with monospecific antitoxin. ELISA was thus a sensitive, specific, and quantifiable technique for the assay of P. aeruginosa exotoxin A in both purified and crude culture materials.

Any formulation of the theory of relativity specifies implicitly or explicitly the exactness or inexactness of the temporal and spatial differentials which occur. In the Minkowski formulation one assumes implicitly the exactness of co-ordinate or common time and the inexactness of proper time. In this paper we examine several other possibilities, especially that of the exactness of proper time and the inexactness of common time. With this assumption one is led to a space—proper-time (SPT) representation of events whicha) yields the customary formal results of the theory including the differential ageing prediction of the « twin paradox »,b) permits an analog of Fermat’s principle to describe both particles and light, andc) leads to a many—proper-time formulation of the relativistic many-body problem essentially equivalent to the Minkowski space formulation. Analogies between this SPT geometry and the geometric approach to thermodynamics, especially as formulated by Carathéodory, suggest the γ-function of relativity is an integrating factor with physical meaning for the many-body problem and also provides insight into the concept of virtual photons. Qualsiasi formulazione della teoria della relatività specifica implicitamente o esplicitamente l’esattezza o l’inesattezza dei differenziali temporali e spaziali che vi si riscontrano. Nella formulazione di Minkowski si pone implicitamente l’ipotesi dell’esattezza della coordinata o del tempo commune e l’inesattezza del tempo proprio. In questo articolo si esaminano numerose altre possibilità, specialmente quella dell’esattezza del tempo proprio e dell’inesattezza del tempo comune. Con questa ipotesi si giunge alla rappresentazione di spazio-tempo proprio (SPT) degli eventi; rappresentazione chea) fornisce i normali risultati formali della teoria compresa la previsione del « paradosso dei gemelli »,b) permette un analogo del principio di Fermat per la descrizione delle particelle e della luce, ec) porta ad una formulazione a molti tempi propri del problema relativistico a molti corpi essenzialmente equivalente alla formulazione dello spazio di Minkowski. Analogie fra questa geometria SPT e l’approccio geometrico alla termodinamica, specialmente come è formulato da Carathéodory, suggeriscono che la funzioneγdella relatività è un fattore integrante con significato fisico per il problema a molti corpi e forniscono anche un mezzo di comprensione del concetto dei fotoni virtuali. Любая формулировка теории относительности точно устанавливает неявно или явно точность или неточность временных или пространственных дифференциалов, которые встречаются в теории. В формулировке Минковского явно предполагается точность координат или обычного времени и неточность собственного времени. В зтой статье мы исследуем некоторые другие воэможности, главным обраэом, точность собственного времени и неточность обычного времени. С помошью зтого предположения мы приходим к представлению пространства-соб ственного времени для событий, котороеa) дает обычные формальные реэультаты теории, включая предскаэание дифференциального старения для «двойникового парадокса»,b) допускает аналог принципа Ферма для описания и частиц и света, иc) приводит к формулировке многих собственных времен для релятивистской проблемы многих тел, по сушеству, зквивалентной формулировке пространства Минковского. Аналогий между зтой геометрией пространства и собственного времени и геометрическим подходом к термодинамике, особенно, как было сформулировано Каратеодори, предполагают, чтоγ-функция теории относительности представляет интегрируюший множитель с фиэическим эначеием для проблемы многих тел, а также обеспечивает правильное представление концепции виртуальных фотонов.