223 research outputs found
Urea drilled with seed affects germination and yield
Trials in 1968 at Burracoppin and York again showed it is safer to topdress urea just before seeding than to drill a mixture of seed and urea.
At all but the lowest urea rates, urea drilled with the seed reduced the number of plants emerging and surviving, and reduced final wheat yields
Characterization of Pseudomonas aeruginosa mutants deficient in the establishment of lysogeny
Mutants of Pseudomonas aeruginosa with impaired ability to establish a lysogenic relationship with temperate bacteriophage (Les-) have been isolated. These les mutations map to two areas of the P. aeruginosa chromosomal map as determined by conjugational and transductional analyses. Two phenotypic classes of Les- mutants were identified. One class of mutations has pleiotropic effects on DNA metabolism. These mutants are unable to recombine genetic material acquired as a result of either conjugation or transduction (Rec-). In addition, the ability of these Les- Rec- mutants to repair UV-induced damage to bacteriophage is reduced (host-cell reactivation deficient, Hcr-). Mutants of the second class are Les-, Rec+, and Hcr+.Peer reviewedMicrobiology and Molecular Genetic
An efficient two-step method to purify very small embryonic-like (VSEL) stem cells from umbilical cord blood (UCB).
Effect and Safety of Meropenem\u2013Vaborbactam versus Best-Available Therapy in Patients with Carbapenem-Resistant Enterobacteriaceae Infections: The TANGO II Randomized Clinical Trial
Introduction: Treatment options for carbapenem-resistant Enterobacteriaceae (CRE) infections are limited and CRE infections remain associated with high clinical failure and mortality rates, particularly in vulnerable patient populations. A Phase 3, multinational, open-label, randomized controlled trial (TANGO II) was conducted from 2014 to 2017 to evaluate the efficacy/safety of meropenem\u2013vaborbactam monotherapy versus best available therapy (BAT) for CRE. Methods: A total of 77 patients with confirmed/suspected CRE infection (bacteremia, hospital-acquired/ventilator-associated bacterial pneumonia, complicated intra-abdominal infection, complicated urinary tract infection/acute pyelonephritis) were randomized, and 47 with confirmed CRE infection formed the primary analysis population (microbiologic-CRE-modified intent-to-treat, mCRE-MITT). Eligible patients were randomized 2:1 to meropenem\u2013vaborbactam (2 g/2 g over 3 h, q8h for 7\u201314 days) or BAT (mono/combination therapy with polymyxins, carbapenems, aminoglycosides, tigecycline; or ceftazidime-avibactam alone). Efficacy endpoints included clinical cure, Day-28 all-cause mortality, microbiologic cure, and overall success (clinical cure + microbiologic eradication). Safety endpoints included adverse events (AEs) and laboratory findings. Results: Within the mCRE-MITT population, cure rates were 65.6% (21/32) and 33.3% (5/15) [95% confidence interval (CI) of difference, 3.3% to 61.3%; P = 0.03)] at End of Treatment and 59.4% (19/32) and 26.7% (4/15) (95% CI of difference, 4.6% to 60.8%; P = 0.02) at Test of Cure;.Day-28 all-cause mortality was 15.6% (5/32) and 33.3% (5/15) (95% CI of difference, 12 44.7% to 9.3%) for meropenem\u2013vaborbactam versus BAT, respectively. Treatment-related AEs and renal-related AEs were 24.0% (12/50) and 4.0% (2/50) for meropenem\u2013vaborbactam versus 44.0% (11/25) and 24.0% (6/25) for BAT. Exploratory risk\u2013benefit analyses of composite clinical failure or nephrotoxicity favored meropenem\u2013vaborbactam versus BAT (31.3% [10/32] versus 80.0% [12/15]; 95% CI of difference, 12 74.6% to 12 22.9%; P < 0.001). Conclusions: Monotherapy with meropenem\u2013vaborbactam for CRE infection was associated with increased clinical cure, decreased mortality, and reduced nephrotoxicity compared with BAT. Clinical Trials Registration: NCT02168946. Funding: The Medicines Company
Peripheral Nerve Activation Evokes Machine-Learnable Signals in the Dorsal Column Nuclei
The brainstem dorsal column nuclei (DCN) are essential to inform the brain of tactile and proprioceptive events experienced by the body. However, little is known about how ascending somatosensory information is represented in the DCN. Our objective was to investigate the usefulness of high-frequency (HF) and low-frequency (LF) DCN signal features (SFs) in predicting the nerve from which signals were evoked. We also aimed to explore the robustness of DCN SFs and map their relative information content across the brainstem surface. DCN surface potentials were recorded from urethane-anesthetized Wistar rats during sural and peroneal nerve electrical stimulation. Five salient SFs were extracted from each recording electrode of a seven-electrode array. We used a machine learning approach to quantify and rank information content contained within DCN surface-potential signals following peripheral nerve activation. Machine-learning of SF and electrode position combinations was quantified to determine a hierarchy of information importance for resolving the peripheral origin of nerve activation. A supervised back-propagation artificial neural network (ANN) could predict the nerve from which a response was evoked with up to 96.8 ± 0.8% accuracy. Guided by feature-learnability, we maintained high prediction accuracy after reducing ANN algorithm inputs from 35 (5 SFs from 7 electrodes) to 6 (4 SFs from one electrode and 2 SFs from a second electrode). When the number of input features were reduced, the best performing input combinations included HF and LF features. Feature-learnability also revealed that signals recorded from the same midline electrode can be accurately classified when evoked from bilateral nerve pairs, suggesting DCN surface activity asymmetry. Here we demonstrate a novel method for mapping the information content of signal patterns across the DCN surface and show that DCN SFs are robust across a population. Finally, we also show that the DCN is functionally asymmetrically organized, which challenges our current understanding of somatotopic symmetry across the midline at sub-cortical levels
A comparison of faecal analysis with backtracking to determine the diet composition and species preference of the black rhinoceros (Diceros bicornis minor)
Monitoring and identification of black rhinoceros <i>Diceros bicomis</i> in Damaraland and the compilation of a population register
Selected Papers from the Rhinoceros Conservation Workshop, Skukuza, Kruger National Park,31 August – 4 September 1988 Identification files for black rhinoceros in Damaraland were begun in 1982. By 1986 almost every individual animal known to occur in the area was listed and documented by means of photographs and relevant data pertaining to individual animals. The maintenance of the identification files is described as are the activities of the monitoring teams. Records show that tracking on foot is the most reliable method of censusing and identifying black rhinoceros in the Damaraland area
Coupled productivity and carbon isotope records in the southwest Pacific Ocean during the late Miocene–early Pliocene biogenic bloom
Biogenic components of sediment accumulated at high rates beneath frontal zones of the Indian and Pacific oceans during the late Miocene and early Pliocene. The δ13C of bulk and foraminiferal carbonate also decreased during this time interval. Although the two observations may be causally linked, and signify a major perturbation in global biogeochemical cycling, no site beneath a frontal zone has independent records of export production and δ13C on multiple carbonate phases across the critical interval of interest. Deep Sea Drilling Project (DSDP) site 590 lies beneath the Tasman Front (TF), an eddy-generating jetstream in the southwest Pacific Ocean. To complement previous δ13C records of planktic and benthic foraminifera at this location, late Neogene records of CaCO3 mass accumulation rate (MAR), Ca/Ti, Ba/Ti, Al/Ti, and of bulk carbonate and foraminiferal δ13C were constructed at site 590. The δ13C records include bulk sediment, bulk sediment fractions (<63 µm and 5–25 µm), and the planktic foraminifera Globigerina bulloides, Globigerinoides sacculifer (with and without sac), and Orbulina universa. Using current time scales, CaCO3 MARs, Ca/Ti, Al/Ti and Ba/Ti ratios are two to three times higher in upper Miocene and lower Pliocene sediment relative to overlying and underlying units. A significant decrease also occurs in all δ13C records. All evidence indicates that enhanced export production – the ‘biogenic bloom’ – extended to the southwest Pacific Ocean between ca. 9 and 3.8 Ma, and this phenomenon is coupled with changes in δ13C – the ‘Chron C3AR carbon shift’. However, CaCO3 MARs peak ca. 5 Ma whereas elemental ratios are highest ca. 6.5 Ma; foraminiferal δ13C starts to decrease ca. 8 Ma whereas bulk carbonate δ13C begins to drop ca. 5.6 Ma. Temporal discrepancies between the records can be explained by changes in the upwelling regime at the TF, perhaps signifying a link between changes in ocean–atmosphere circulation change and widespread primary productivity
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