Availability analysis of the traveling-wave maser amplifiers in the deep space network. Part 1: The 70-meter antennas

The results of the reliability and availability analyses of the individual S- and X-band traveling-wave maser (TWM) assemblies and their operational configurations in the 70-meter antennas of NASA's Deep Space Network (DSN) are described. For the period 1990 through 1991, the TWM availability parameters for the Telemetry Data System are: mean time between failures (MTBF), 930 hr; mean time to restore services (MTTRS), 1.4 hr; and the average availability, 99.85 percent. In previously published articles, the performance analysis of the TWM assemblies was confined to the determination of the parameters specified above. However, as the mean down time (MDT) for the repair of TWM's increases, the levels of the TWM operational availabilities and MTTRS are adversely affected. A more comprehensive TWM availability analysis is presented to permit evaluation of both MTBF and MDT effects. Performance analysis of the TWM assemblies, based on their station monthly failure reports, indicates that the TWM's required MTBF and MDT levels of 3000 hr and 36 to 48 hr, respectively, have been achieved by the TWM's only at the Canberra Deep Space Station (DSS 43). The Markov Process technique is employed to develop suitable availability measures for the S- and X-band TWM configurations when each is operated in a two-assembly standby mode. The derived stochastic expressions allow for the evaluation of those configurations' simultaneous availability for the Antenna Microwave Subsystem. The application of these expressions to demonstrate the impact of various levels of TWM maintainability (or MDT) on their configurations' operational availabilities is presented for each of the 70-m antenna stations

Isolation of Trichophyton mentogrophytes var mentogrophytes from naturally infected laboratory albino rats: experimental infection and treatment in rabbits

The present study demonstrated for the first time the occurrence of dermatophytosis in naturally infected rats and from asymptomatic and from breeding boxes of white rats kept in animal housing of college of Veterinary Medicine, University of Dohuk, Iraq. The prevalence rate of infection was (28%), clinically infected rats characterized by appearance of scaly ovoid type lesions with crusty edge and patch of hair loss mostly seen on the back, neck and face of the infected rats, itching was reported in some rats. Only one species of the trichophyton, T. mentogrophytes var mentogrophytes was isolated with growth rate (85.71%) of samples collected from clinically infected rats, and (28.57%) from asymptomatic and from breeding cages, the growth was observed within the 21 days at 25ºC on Sabouraud's Dextrose Agar. Lacto phenol cotton blue staining slides of T. mentogrophytes var mentogrophytes revealed both microconidia and macroconidia. Microconidia found in numerous numbers often in dense cluster which were hyaline, smooth walled and predominantly spherical to sub spherical in shape, varying numbers of chlamydoconidia. Spiral hyphae and smooth, thin walled clavate shaped multicelled macroconidia were also present. The study also dealt with experimental infection in rabbits with T. mentogrophytes var mentogrophytes and treated by two drugs, natural herbal preparation of acidic pomegranate (Punica granatum) fruit and synthetic nystatine ointment. The complete recovery of lesions was recorded after 14 days and 21 days of topical application of a pomegranate and nystatine ointment for 5 successive days respectively

Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana reduce the survival of Xenopsylla brasiliensis larvae (Siphonaptera: Pulicidae).

Entomopathogenic fungi, particularly those belonging to the genera Metarhizium and Beauveria have shown great promise as arthropod vector control tools. These agents, however, have not been evaluated against flea vectors of plague. A 3-h exposure to the fungi coated paper at a concentration of 2 × 108 conidia m-2 infected >90% of flea larvae cadavers in the treatment groups. The infection reduced the survival of larvae that had been exposed to fungus relative to controls. The daily risk of dying was four- and over three-fold greater in larvae exposed to M. anisopliae (HR = 4, p<0.001) and B. bassiana (HR = 3.5, p<0.001) respectively. Both fungi can successfully infect and kill larvae of X. brasiliensis with a pooled median survival time (MST±SE) of 2±0.31 days post-exposure. These findings justify further research to investigate the bio-control potential of entomopathogenic fungi against fleas.\ud \u

Staple Line Polyposis and Cytomegalovirus Infection after Stapled Haemorrhoidectomy

Early bleeding after stapled haemorrhoidectomy (SH) is not uncommon. Late and persistent bleeding occurring weeks or months after SH, however, is rare; it has only been described in more than 10% of cases. It is attributed to the development of inflammatory polyps at the staple line. Occurrence of rectal bleeding in the presence of palpable polypoid lesions at the stapled anastomotic line can cause diagnostic confusions, and it is not uncommon that such lesions are initially confused with rectal carcinoma. We report a case of a 38-year-old male who presented with persistent rectal bleeding some 6 months after SH performed in another hospital. Rectal and colonoscopic examinations revealed polypoid lesions at the anastomotic line. The biopsy failed to confirm malignancy, but identified cytomegalovirus (CMV) infection. The development of multiple inflammatory polypoid lesions in conjunction with CMV infection at the stapled anastomotic line has caused a diagnostic confusion, but – after exclusion of cancer – this complication was efficiently treated by CMV infection eradication combined with surgical excision of the remaining polyps due to persistence of bleeding. This case is reported to highlight late bleeding due to inflammatory polyps after SH and to increase the awareness of surgeons and gastroenterologists of this benign but somewhat common complication

Elastography in Chronic Liver Diseases

Elastography is useful for diagnosing and grading hepatic fibrosis in patients with chronic liver diseases (CLD). In addition, it may be used as a noninvasive tool for surveillance and prognostication of patients with complications related to CLD. Elastography uses real-time ultrasound to assess for tissue elasticity and is a fast, simple, reproducible, and reliable method for noninvasive liver fibrosis evaluation. Management of chronic liver disease is dependent on the grade of liver fibrosis to ascertain the urgency and choice of treatment and advice on further screening for cirrhosis and hepatocellular carcinoma. This chapter will highlight the role of elastography in the evaluation of chronic liver disease including hepatitis B and C and HIV-related liver disease and nonalcoholic fatty liver disease (NAFLD)

Etapes et méthodes de formulation d’aliment de volaille : Une synthèse bibliographique

L’alimentation joue un rôle déterminant dans la réussite et la rentabilité économique des productions avicoles. Lors de la formulation d’un aliment efficient, son coût et sa qualité nutritionnelle qui permet de couvrir tous les besoins nutritionnels essentiels des volailles doivent être considérés. Ce travail basé sur la collecte des articles, fait la revue des étapes à suivre pour la formulation d’aliment de volaille et décrit les méthodes qui ont été utilisées dans la formulation d’aliment de volaille. Le carré de Pearson, l’équation algébrique simultanée, la méthode matérielle et la méthode essai et erreur sont des méthodes manuelles utilisées pour la formulation d’aliment de volaille. Les programmations linéaire, non linéaire, multi objective et quadratique sont quant à elles les méthodes de programmation mathématique de formulation d’aliment de volaille. Les méthodes manuelles permettent de faire une formulation avec peu d’ingrédient et les méthodes mathématiques permettent de faire une formulation à moindre coût.© 2015 International Formulae Group. All rights reserved.Mots clés: Aliment de volaille, formulation, étapes, méthode

First report of Metarhizium anisopliae IP 46 pathogenicity in adult Anopheles gambiae s.s. and An. arabiensis (Diptera; Culicidae).

The entomopathogenic fungus Metarhizium anisopliae isolate IP 46, originating from a soil sample collected in 2001 in the Cerrado of Central Brazil, was tested for its ability to reduce the survival of adult male and female Anopheles gambiae s.s. and An. arabiensis mosquitoes. A 6-h exposure to the fungus coated on test paper at a concentration of 3.3 x 106 conidia cm-2 reduced the daily survival of both mosquito species (HR = 3.14, p < 0.001), with higher risk of dying in An. gambiae s.s relative to An. arabiensis (HR = 1.38, p < 0.001). Fungal sporulation was observed in >95% of mosquito cadavers in the treatment groups. The results indicate that M. anisopliae IP 46 has the potential to be a bio-control agent for African malaria vector species, and is a suitable candidate for further research and development

The effect of N-acetylcysteine on the sensory retina of male albino rats exposed prenatally to cypermethrin

Background: Cypermethrin (CYP), a pyrethroid that is globally used in the field and house to fight the pests. CYP can induce cellular toxicity and cross the placental barrier. N-acetylcysteine (NAC) can fight the prenatal exposure to the inflammation. This work aimed to study, for the first time, the effects of NAC on the sensory retina of male albino rats exposed prenatally to cypermethrin. Materials and methods: Twenty-four sexually mature female albino rats and 12 male albino rats were allowed for mating and divided equally into the following groups: group I (control group): kept without treatment; group II (NAC group): received 1 g/kg/day NAC diluted in distilled water orally by gastric tube from the 7th day of gestation till delivery; group III (CYP group): received 12 mg/kg/day of cypermethrin orally by gastric tube from the 7th day of gestation till delivery; group IV (CYP and NAC group): received 12 mg/kg/day of cypermethrin and 1 g/kg/day of NAC. The ten male offspring of each group were divided into subgroups a and b that were sacrificed at the age of 7th and 14th days postnatal, respectively. At the end of the experiment, the eye samples were subjected to histological, immunohistochemical and morphometric studies. Results: Concerning the different previous studies, the sensory retina of CYP subgroups showed vacuolation of the inner and outer plexiform layers, dilated congested blood vessels, hyalinisation and disorganisation of the photoreceptor layer. Also, the expression of collagen IV and caspase 3 (a marker of apoptosis) was up-regulated in the CYP subgroups. Conclusions: N-acetylcysteine significantly protected the sensory retina from the damaging effects of CYP. NAC could be considered as a good protective agent against the damaging effect of CYP on the sensory retina