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Although Chlamydia causes disease of the urethra and prostate of male koalas, its impact on the testis and epididymis has not been examined. This study describes chronic-active and granulomatous orchitis and epididymitis with interstitial fibrosis associated with infection by Chlamydia pecorum in 2 of 18 adult male koalas being euthanized at a koala hospital, 8 of which also had chlamydial prostatitis. By immunohistochemistry and transmission electron microscopy, chlamydial inclusions were demonstrated within Sertoli cells directly associated with mild inflammation surrounding intact seminiferous and epididymal tubules, marked pyogranulomatous inflammation around disrupted tubules, replacement of tubules by interstitial fibrosis, and aspermia. The presence of C. pecorum but not Chlamydia pneumoniae was detected by quantitative polymerase chain reaction of formalin-fixed tissues of the left and right testes and right epididymis in 1 animal. This is the first report of orchitis and epididymitis in a koala infected with C. pecorum. [ABSTRACT FROM AUTHOR]

Major histocompatibility complex class II (MHCII) genes code for proteins that bind and present antigenic peptides and trigger the adaptive immune response. We present a broad geographical study of MHCII DA β1 (DAB) and DB β1 (DBB) variants of the koala (Phascolarctos cinereus; n=191) from 12 populations across eastern Australia, with a total of 13 DAB and 7 DBB variants found. We identified greater MHCII variation and, possibly, additional gene copies in koala populations in the north (Queensland and New South Wales) relative to the south (Victoria), confirmed by STRUCTURE analyses and genetic differentiation using analysis of molecular variance. The higher MHCII diversity in the north relative to south could potentially be attributed to (i) significant founder effect in Victorian populations linked to historical translocation of bottlenecked koala populations and (ii) increased pathogen-driven balancing selection and/or local genetic drift in the north. Low MHCII genetic diversity in koalas from the south could reduce their potential response to disease, although the three DAB variants found in the south had substantial sequence divergence between variants. This study assessing MHCII diversity in the koala with historical translocations in some populations contributes to understanding the effects of population translocations on functional genetic diversity. [ABSTRACT FROM AUTHOR]

Griffith, J.E., Higgins, D.P., Li, K.M., Krockenberger, M.B., Govendir, M. Absorption of enrofloxacin and marbofloxacin after oral and subcutaneous administration in diseased koalas ( Phascolarctos cinereus). J. vet. Pharmacol. Therap. doi: 10.1111/j.1365-2885.2009.01172.x. Koalas ( n = 43) were treated daily for up to 8 weeks with enrofloxacin: 10 mg/kg subcutaneously (s.c.), 5 mg/kg s.c., or 20 mg/kg per os (p.o.); or marbofloxacin: 1.0-3.3 mg/kg p.o., 10 mg/kg p.o. or 5 mg/kg s.c. Serial plasma drug concentrations were determined on day 1 and again at approximately 2 weeks, by liquid chromatography. The median (range) plasma maximum concentrations ( C) for enrofloxacin 5 mg/kg s.c. and 10 mg/kg s.c. were 0.83 (0.68-1.52) and 2.08 (1.34-2.96) μg/mL and the median (range) T were 1.5 h (1-2) and 1 h (1-2) respectively. Plasma concentrations of orally dosed marbofloxacin were too low to be quantified. Oral administration of enrofloxacin suggested absorption rate limited disposition pharmacokinetics; the median (range) C for enrofloxacin 20 mg/kg p.o. was 0.94 (0.76-1.0) μg/mL and the median (range) T was 4 h (2-8). Oral absorption of both drugs was poor. Plasma protein binding for enrofloxacin was 55.4 ± 1.9% and marbofloxacin 49.5 ± 5.3%. Elevations in creatinine kinase activity were associated with drug injections. Enrofloxacin and marbofloxacin administered at these dosage and routes are unlikely to inhibit the growth of chlamydial pathogens in vivo. [ABSTRACT FROM AUTHOR]

The fabrication of cylindrical probes having diameters as small as 50 nm is described in this article. The planar endface (advantageously oriented perpendicular to the axis of the cylindrical probe) and sharp 90° corners of the end portion of the probe enable accurate measurement of a feature being scanned, even at sudden jumps in the surface. Conical and flaired probes can also be fabricated with variations of this technique. The fabrication techniques described in this article are simple and inexpensive; only a Teflon beaker, optical fiber, etching solution, polymer solution, fiber cleaver, and optical microscope are necessary. [ABSTRACT FROM AUTHOR]

There exists interest in the measurement of small forces for applications such as microtopography of semiconductor devices and atomic force microscopy. A new method is introduced here in which a small silicon beam, that is acted on by the external force of interest, has its position sensed by an rf phase shift technique. The position information in turn is fed back via electrostatic forces to continuously rebalance the beam about its central support. This force-feedback approach provides high sensitivity, submillisecond response, inherent force calibration, and electronically controlled stiffness. [ABSTRACT FROM AUTHOR]

Probe tips for scanning tunneling microscopy have been sharpened using focused ion beam milling. Reproducible tips were formed on polycrystalline W and Pt-Ir shanks, but this technique is not limited to these materials. The tips were found to have cone angles of 12±3° and radii of curvature as sharp as 4 nm. Focused ion beam machining allows precise control of the final shape of the tips which is important in metrology measurements of various nanostructure devices. [ABSTRACT FROM AUTHOR]

The article discusses the importance of the Mississippi River to the state of Iowa and the North-West. The author states that Iowa lies between the Mississippi and Missouri rivers which makes the state essential for trade. The article talks about some obstructions at certain points in the Mississippi River which slow down communication between ships. The author stresses the need to remove these obstructions and says that citizen's of Iowa should help. Subjects of the article also include canals, a channel at Rock Island, Illinois, and the growing of wheat in Iowa.

The article discusses the rapids of the Des Moines and Mississippi rivers in Iowa. The author states that the rapids, known as the Lower Rapids, are located near the mouth of the Des Moines river and extend 11 miles from Keokuk to Montrose, Iowa. The article details the physical attributes of the river, including the river bottom, the outlet of the lake, and their gradual descent. Subjects of the article also include the removal of a rock near the rapids, how to navigate the channel at Montrose, and the construction of locks and canals to help boats travel the rapids.

The article discusses magnesium limestone in Iowa and the use of it as building material. The author states that magnesium limestone belongs to the subcarboniferous age. He explains that the limestone between Keokuk, Iowa and St. Louis, Missouri is difficult to draw from the earth. The reasons this limestone makes a good building material are listed. The color and structure of the limestone are discussed. The author mentions how the limestone was used to construct three locks in the rapids of the Des Moines river.