Clostridium perfringens is an anaerobic, spore-forming bacterium that may lead to necrotic enteritis, resulting in poor feed efficiency and increased mortality in chickens. It is estimated that C. ...perfringens infects almost 1 million people in the United States every year. The objective of this research was to compare the Fung double tube (FDT) and conventional Petri plates using 3 different media to detect and enumerate Clostridium spp. in chicken intestines. Nine Cobb 500 broilers were randomly selected and euthanized at 21 and 42 d of age for a total of 18 samples. The jejunum and ileum from each broiler were harvested and studied in 2 methods and 3 media combinations, utilizing a 2 × 3 factorial totaling 6 treatments. The 2 methods were FDT and conventional Petri plates, and the 3 media were Shahidi-Ferguson Perfringens (SFP) with egg yolk supplement, polymyxin B, and kanamycin (E); SFP with polymyxin B and kanamycin (P); and SFP with d-cycloserine (C). Enumerations were performed after 24 h of incubation at 37°C. At 21 d, counts using medium C with FDT (4.51 log10 cfu/g) and plates (2.38 log10 cfu/g) were higher (P < 0.05) than using media E or P. On d 42, there were no differences among plate treatments and medium E had the highest counts (0.98 log10 cfu/g). Of all the FDT, medium C (5.35 log10 cfu/g) had the highest counts (P < 0.05), followed by medium P (3.54 log10 cfu/g). This study illustrates that the FDT method is able to enumerate Clostridium spp. at higher levels (P < 0.001) than the conventional Petri plate method; therefore, the FDT should be implemented and further explored.
Design, calibration, and performance of the MINERvA detector Aliaga, L.; Bagby, L.; Baldin, B. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2014, Letnik:
743
Journal Article
Recenzirano
Odprti dostop
The MINERvA66Main INjector ExpeRiment ν-A. experiment is designed to perform precision studies of neutrino-nucleus scattering using νμ and ν¯μ neutrinos incident at 1–20GeV in the NuMI beam at ...Fermilab. This article presents a detailed description of the MINERvA detector and describes the ex situ and in situ techniques employed to characterize the detector and monitor its performance. The detector is composed of a finely segmented scintillator-based inner tracking region surrounded by electromagnetic and hadronic sampling calorimetry. The upstream portion of the detector includes planes of graphite, iron and lead interleaved between tracking planes to facilitate the study of nuclear effects in neutrino interactions. Observations concerning the detector response over sustained periods of running are reported. The detector design and methods of operation have relevance to future neutrino experiments in which segmented scintillator tracking is utilized.
An abstract of a study by Rude et al evaluating the effects of a formaldehyde based feed additive on free lysine is presented. these study conditions reflect an experimental scenario. There was no ...effect of d post-mix (P = 0.1253) and no interaction between SC inclusion and L-lysine HCl level (P = 0.6880). Even with Sal CURB levels being higher than the label requirements there were no effects of Sal CURB inclusion on free lysine.
MINERvA neutrino detector response measured with test beam data Aliaga, L.; Altinok, O.; Araujo Del Castillo, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2015, Letnik:
789, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The MINERvA collaboration operated a scaled-down replica of thesolid scintillator tracking and sampling calorimeter regions of the MINERvA detector in a hadron test beam at the Fermilab Test Beam ...Facility. This paper reports measurements with samples of protons, pions, and electrons from 0.35 to 2.0GeV/c momentum. The calorimetric response to protons, pions, and electrons is obtained from these data. A measurement of the parameter in Birks׳ law and an estimate of the tracking efficiency are extracted from the proton sample. Overall the data are well described by a Geant4-based Monte Carlo simulation of the detector and particle interactions with agreements better than 4% for the calorimetric response, though some features of the data are not precisely modeled. These measurements are used to tune the MINERvA detector simulation and evaluate systematic uncertainties in support of the MINERvA neutrino cross-section measurement program.
To assess the false positive rate of blood lead (BPb) determinations on samples obtained by fingerstick from children screened in an urban clinic.
From a single fingerstick (N = 1573), blood was ...collected in a capillary tube for determining lead concentration (CPb) by graphite furnace and an additional sample was absorbed onto a filter paper for determining lead concentration (FPb) by atomic absorption spectrophotometry with Delves cup. Zinc protoporphyrin (ZPP) was measured immediately and a confirmatory venous lead (VPb) specimen was obtained at the same visit if the ZPP was > or = 35 micrograms/dL (0.6 mumol/L); children with either a CPb or FPb > or = 15 micrograms/dL (0.7 mumol/L) were later recalled for determining VPb.
For the 172 children who had a VPb on the same day as the screening tests, the false positive rates (95% confidence intervals) at a lead threshold of 15 micrograms/dL (0.7 mumol/L) were: CPb, 13.5% (6.7-20.3); FPb, 19.1% (11.8-26.4). Analyses using all 679 screens with a paired venous specimen (mean delay between screen and venous testing = 30 days) yielded much higher false positive rates (CPb, 31.3%; FPb, 46.0%).
Screening for lead poisoning is feasible within an urban pediatric clinic by direct measurement of lead concentration in blood samples obtained by fingerstick. The false positive rate that can be obtained is acceptable given the precision of measuring BPb concentration. Practitioners using a staged screening protocol may incorrectly attribute a higher false positive rate to the screening tests, when much of the error may be due to the temporal variability of BPb resulting from both biologic variability in BPb concentration and intermittent exposures.
Hypoxaemia may cause postoperative confusion after operations for hip fractures in elderly patients. Twenty-two consecutive patients, with a median age of 73 years, had fractures fixed with a sliding ...hip screw within 48 hours of admission. The incidence of hypoxaemia was investigated postoperatively using a pulse oximeter. We have demonstrated that this complication occurs frequently on the first day and severe hypoxaemia can be prevented by supplementary oxygen therapy. Our results support the hypothesis that postoperative confusion can be caused by hypoxaemia.
Diagnostic ultrasound was used in 103 patients with a clinically suspected fracture of the scaphoid bone in order to achieve an early diagnosis. There were 48 women and 55 men aged 10-75 years (mean ...31.4 years) tested with ultrasound. Of the patients, 72 were tested within 3 days after injury the remainder between 4 and 42 days. Fracture was confirmed radiologically in 27. We found that the ultrasound test, applied with a frequency of 1 MHz and intensity of 0.5 W/cm2 and 2.0 W/cm2 for 30s, had a sensitivity of 37 per cent and a specificity of 61 per cent. We thus conclude that ultrasound is not suitable for early diagnosis of scaphoid fracture.
For most of the chemical substances that are subject to regulatory and industrial decision making, important toxicological data are missing. The available dataset is often difficult to interpret, and ...the differences between alternative, scientifically reasonable interpretations may have major impact on decision making. Since such uncertainties are an important factor in decision making it is essential that they be reported in a transparent and understandable way. In order to clarify how toxicologists report uncertainties, 30 risk assessments for one and the same substance (trichloroethylene) from the years 1973–2001 were searched for phrases indicating uncertainty. These phrases can be divided between four categories: contentual, epistemic, conditionalising, and inferential uncertainty indicators. A typology of uncertainty indicators, based on these categories, is proposed. It is concluded that the use of uncertainty indicators in these texts is not transparent and that the development of standardised uncertainty indicators should significantly improve communications both within the scientific community and between scientists and policymakers.
The authors describe 4 patients who had functioning distal splenorenal shunts despite obstruction of the left renal vein at its insertion into the inferior vena cava. The angiographic technique and ...findings of left renal vein evaluation in 40 shunted patients are reviewed. There were two important findings. First, no correlation existed between the degree of portal hypertension and the degree of filling of collateral tributaries of renal veins. Second, obstruction of the left renal vein does not impair a splenorenal shunt if good collateral pathways are present.
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