SURGICAL DEMONSTRATION OF PRESSURE DIFFERENTIAL THROUGH AN OPTIC DISK PIT.

Purpose: To demonstrate intraoperative dynamic flow through an optic disk pit.

Methods: Retrospective interventional case report.

Results: Surgical management of an optic disk pit involved standard, 25-gauge, pars plana vitrectomy, induction of posterior hyaloid separation with triamcinolone stain, temporal peripapillary laser, and SF 6 gas.

Generalist bird exhibits site-dependent resource selection.

Quantifying resource selection (an organism's disproportionate use of available resources) is essential to infer habitat requirements of a species, develop management recommendations, predict species responses to changing conditions, and improve our understanding of the processes that underlie ecological patterns. Because study sites, even within the same region, can differ in both the amount and the arrangement of cover types, our objective was to determine whether proximal sites can yield markedly different resource selection results for a generalist bird, northern bobwhite (). We used 5 years of telemetry locations and newly developed land cover data at two, geographically distinct but relatively close sites in the south-central semi-arid prairies of North America.

Woody encroachment happens via intensification, not extensification, of species ranges in an African savanna.

Widespread woody encroachment is a prominent concern for savanna systems as it is often accompanied by losses in productivity and biodiversity. Extensive ecosystem-level work has advanced our understanding of its causes and consequences. However, there is still debate over whether local management can override regional and global drivers of woody encroachment, and it remains largely unknown how encroachment influences woody community assemblages.

Overcoming an "irreversible" threshold: A 15-year fire experiment.

A key pursuit in contemporary ecology is to differentiate regime shifts that are truly irreversible from those that are hysteretic. Many ecological regime shifts have been labeled as irreversible without exploring the full range of variability in stabilizing feedbacks that have the potential to drive an ecological regime shift back towards a desirable ecological regime. Removing fire from grasslands can drive a regime shift to juniper woodlands that cannot be reversed using typical fire frequency and intensity thresholds, and has thus been considered irreversible.

Ocular metastasis as initial presentation in breast cancer.

Two patients presented to their ophthalmologists with vision disturbances. On ocular examination, retinopathic lesions were observed. On subsequent examination, these lesions were diagnosed as metastases of breast cancer.

Fatal air embolism during endoresection of choroidal melanoma.

Purpose: To describe a case of intraoperative mortality because of air embolism during resection of a choroidal melanoma by pars plana vitrectomy.

Methods: Retrospective interventional case report.

Results: A 69-year-old man died unexpectedly at the time of pars plana vitrectomy.

Estimating seasonal nitrogen removal and biomass yield by annuals with the extended logistic model.

The Extended Logistic Model (ELM) has been previously shown to adequately describe seasonal biomass production and N removal with respect to applied N for several types of annuals and perennials. In this analysis, data from a corn (Zea mays L.) study with variable applied N were analyzed to test hypotheses that certain parameters in the ELM are invariant with respect to site specific attributes, like environmental conditions and soil type.

Brachytherapy and endoresection for choroidal melanoma: a cohort study.

Aim: To report and compare the outcomes of brachytherapy and endoresection in the conservative treatment of medium sized choroidal melanoma.

Methods: A retrospective cohort study. Medium tumours were defined as 2.

Accumulation of biomass and mineral elements with calendar time by cotton: application of the expanded growth model.

Accumulation of plant biomass (Mg ha(-1)) with calendar time (wk) occurs as a result of photosynthesis for green land-based plants. A corresponding accumulation of mineral elements (kg ha(-1)) such as nitrogen, phosphorus, and potassium occurs from the soil through plant roots. Field data from literature for the warm-season annual cotton (Gossypium hirsutum L.

Accumulation of biomass and mineral elements with calendar time by corn: application of the expanded growth model.

The expanded growth model is developed to describe accumulation of plant biomass (Mg ha(-1)) and mineral elements (kg ha(-1)) in with calendar time (wk). Accumulation of plant biomass with calendar time occurs as a result of photosynthesis for green land-based plants. A corresponding accumulation of mineral elements such as nitrogen, phosphorus, and potassium occurs from the soil through plant roots.

Model of yield response of corn to plant population and absorption of solar energy.

Biomass yield of agronomic crops is influenced by a number of factors, including crop species, soil type, applied nutrients, water availability, and plant population. This article is focused on dependence of biomass yield (Mg ha(-1) and g plant(-1)) on plant population (plants m(-2)). Analysis includes data from the literature for three independent studies with the warm-season annual corn (Zea mays L.

Extracapsular cataract extraction with posterior chamber lens implantation in primary angle-closure glaucoma.

Purpose: To evaluate long-term intraocular pressure (IOP) control after extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens (IOL) implantation in patients with primary angle-closure glaucoma.

Setting: Ophthalmology Department, Groote Schuur Hospital, Cape Town, South Africa.

Methods: This retrospective study comprised 17 patients (19 eyes) with primary angle-closure glaucoma who had ECCE and posterior chamber IOL implantation.

The effect of reducing the exposure time of mitomycin C in glaucoma filtering surgery.

Background: The use of adjunctive intraoperative mitomycin C has considerably improved the success rate of glaucoma filtering surgery. However, the ideal concentration and exposure time of mitomycin C is unknown. The purpose of this study is to determine whether a satisfactory surgical outcome can be achieved with a lower incidence of adverse side effects by using a shorter exposure time of mitomycin C than has been recommended previously.

16S ribosomal RNA sequence analysis for determination of phylogenetic relationship among methylotrophs.

16S ribosomal RNAs (rRNA) of 12 methylotrophic bacteria have been almost completely sequenced to establish their phylogenetic relationships. Methylotrophs that are physiologically related are phylogenetically diverse and are scattered among the purple eubacteria (class Proteobacteria). Group I methylotrophs can be classified in the beta- and the gamma-subdivisions and group II methylotrophs in the alpha-subdivision of the purple eubacteria, respectively.

Three dehalogenases and physiological restraints in the biodegradation of haloalkanes by Arthrobacter sp. strain HA1.

Arthrobacter sp. strain HA1 utilizes 18 C2-to-C8 1-haloalkanes for growth and synthesizes an inducible 1-bromoalkane debrominase of unknown physiological function (R. Scholtz, T.

Dichloromethane dehalogenase with improved catalytic activity isolated from a fast-growing dichloromethane-utilizing bacterium.

A methylotrophic bacterium, denoted strain DM11, was isolated from groundwater and shown to utilize dichloromethane or dibromomethane as the sole carbon and energy source. The new isolate grew at the high rate of 0.22 h-1 compared with 11 previously characterized dichloromethane-utilizing bacteria (micromax, 0.

Transformation of tetrachloromethane to dichloromethane and carbon dioxide by Acetobacterium woodii.

Five anaerobic bacteria were tested for their abilities to transform tetrachloromethane so that information about enzymes involved in reductive dehalogenations of polychloromethanes could be obtained. Cultures of the sulfate reducer Desulfobacterium autotrophicum transformed some 80 microM tetrachloromethane to trichloromethane and a small amount of dichloromethane in 18 days under conditions of heterotrophic growth. The acetogens Acetobacterium woodii and Clostridium thermoaceticum in fructose-salts and glucose-salts media, respectively, degraded some 80 microM tetrachloromethane completely within 3 days.

Characterization of 1-chlorohexane halidohydrolase, a dehalogenase of wide substrate range from an Arthrobacter sp.

1-Chlorohexane halidohydrolase from Arthrobacter sp. strain HA1 was purified to homogeneity by fractional precipitation, ion-exchange chromatography, gel filtration, and high-performance liquid chromatography gel filtration. The enzyme was a monomer with a molecular weight of about 37,000; its amino acid composition and N-terminal sequence were determined.