Experimental verification of principal losses in a regulatory particulate matter emissions sampling system for aircraft turbine engines.

A sampling system for measuring emissions of nonvolatile particulate matter (nvPM) from aircraft gas turbine engines has been developed to replace the use of smoke number and is used for international regulatory purposes. This sampling system can be up to 35 m in length. The sampling system length in addition to the volatile particle remover (VPR) and other sampling system components lead to substantial particle losses, which are a function of the particle size distribution, ranging from 50 to 90% for particle number concentrations and 10-50% for particle mass concentrations. The particle size distribution is dependent on engine technology, operating point, and fuel composition. Any nvPM emissions measurement bias caused by the sampling system will lead to unrepresentative emissions measurements which limit the method as a universal metric. Hence, a method to estimate size dependent sampling system losses using the system parameters and the measured mass and number concentrations was also developed (SAE 2017; SAE 2019). An assessment of the particle losses in two principal components used in ARP6481 (SAE 2019) was conducted during the VAriable Response In Aircraft nvPM Testing (VARIAnT) 2 campaign. Measurements were made on the 25-meter sample line portion of the system using multiple, well characterized particle sizing instruments to obtain the penetration efficiencies. An agreement of ± 15% was obtained between the measured and the ARP6481 method penetrations for the 25-meter sample line portion of the system. Measurements of VPR penetration efficiency were also made to verify its performance for aviation nvPM number. The research also demonstrated the difficulty of making system loss measurements and substantiates the E-31 decision to predict rather than measure system losses.

Nasal and cloacal bacteria in free-ranging desert tortoises from the western United States.

Aerobic bacteria were collected from three free-ranging desert tortoise (Gopherus agassizii) populations in the eastern Mojave Desert (Arizona, Utah; USA) from 1989 to 1993, and from two free-ranging populations in the central Sonoran Desert (Arizona, USA) from 1990 to 1994. Six species of nasal bacteria and 18 species of cloacal bacteria were identified. At least one potential pathogen was found in the nasal cavity (Pasteurella testudinis), and at least two potential pathogens in the cloaca (Pseudomonas spp., Salmonella spp.).

Osteonecrosis in sickle cell trait.

Osteonecrosis is common in sickle cell anemia but has been rarely reported with sickle cell trait. Two cases of osteonecrosis of the femoral head caused by sickle cell trait are presented. One patient's diagnosis was delayed because the association of osteonecrosis and sickle cell trait was not recognized. The previous reported cases of this association are discussed, emphasizing diagnostic implications for 12 black patients presenting with hip pain.

Septic arthritis due to Aerococcus viridans.

A 20-year-old woman was found to have septic arthritis of the hip due to Aerococcus viridans. This organism closely resembles Streptococcus viridans, but forms gram positive tetrads rather than chains in broth media. The organism has been reported rarely to cause endocarditis and one case of osteomyelitis has been observed. To our knowledge septic arthritis due to Aerococcus viridans has not been previously reported.

Ram epididymitis: A clinical report.

Two hundred and five ram lambs originating from several sources were assembled for a ram performance trial. All rams were immunized with a commercial Brucella ovis bacterin. Four rams developed clinical evidence of epididymitis during the 150 day trial. Actinobacillus seminis was identified as the causative agent.

Further studies on trypanosomes in game animals in Wyoming II.

Further studies on moose revealed trypanosomes in two captive moose (Alces alces shirasi) and in 4 of 7 free-ranging moose in Wyoming by blood culture. Two free-ranging moose from Utah were negative. One of two additional captive moose calves was positive for trypanosomes. Trypanosomes also were detected in blood cultures of 8 of 39 American Bison (Bison bison) being brought into Wyoming from Nebraska. Nineteen additional bison were negative for trypanosomes by blood cultures. Identification of species was not possible due to the failure to obtain bloodstream trypomastigotes from this host. Trypanosomes were recovered from 8 of 57 pronghorn antelope (Antilocapra americana). This is the first report of Trypanosoma sp. from bison and from pronghorn; the trypanosome from moose was identified as Trypanosoma cervi from bloodstream trypomastigotes. In 1978, natural transplacental transmission of trypanosomes was found to occur in 1 of 15 mule deer (Odocoileus hemionus) fetuses, examined near term by blood culture. No trypanosomes were found in 18 male deer fetuses examined in 1979. Of 100 free-ranging elk from western Wyoming examined by blood culture in 1979, 71 were infected. These data are compared with data from 1973-74.

Continuous cultivation of Trypanosoma theileri at 37 C in bovine cell culture.

Trypanosoma theileri was cultivated at 37 C in bovine bone marrow cell culture through 50 consecutive subcultures. Medium 199, supplemented with Bacto-peptone, vitamin B12, and fetal bovine serum, was utilized both for primary and continuous cultivation. The number of trypanosomes produced in culture averaged 8 x 10(6) (1-26 x 10(6)) trypanosomes/ml. In each subculture the organisms divided as epimastigotes and transformed into trypomastigotes; a round from was observed during the stationary and declining phase of growth. Gradual changes such as increased generation time, size reduction, and decreased trypomastigote production were observed as subculturing progressed. Cultured trypanosomes were infective for the bovine through the 48th serial transfer and could be cultivated at 26 degrees C.

A bovine herpesvirus isolated from sheep.

A viral agent was isolated from the trachea of a lamb that was suffering from a respiratory disorder. The physical and chemical properties of the isolates are characteristic of the herpesvirus group. It contains DNA in its virion, is ether sensitive, acid labile at pH 3.0 and heat labile at 56 degrees C after five minutes. The cytopathology observed provided further evidence of a herpesvirus isolate. The neutralization of the infectivity of the isolate with antiserum to bovine herpesvirus 1 is evidence that it should be considered an isolate of bovine herpesvirus 1. It is concluded that this is a report of a bovine herpesvirus infection in sheep.