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Understanding of the pre-development, baseline denudation rates that deliver sediment to the Great Barrier Reef (GBR) has been elusive. Cosmogenic 10Be in sediment is a useful integrator of denudation rates and sediment yields averaged over large spatial and temporal scales. This study presents 10Be data from 71 sites across 11 catchments draining to the GBR: representing 80% of the GBR catchment area and provide background sediment yields for the region. Modern, short-term, sediment yields derived from suspended load concentrations are compared to the 10Be data to calculate an Accelerated Erosion Factor (AEF) that highlights denudation "hot-spots" where sediment yields have increased over the long-term background values. The AEF results show that 58% basins have higher modern sediment yields than long-term yields. The AEF is considered a useful approach to help prioritise on-ground investments in remediation and the additional measured empirical data in this paper will help support future predictive models.

Understanding of the pre-development, baseline denudation rates that deliver sediment to the Great Barrier Reef (GBR) has been elusive. Cosmogenic

Purpose To restore 12-lead electrocardiographic (ECG) signal fidelity inside MRI by removing magnetic field gradient-induced voltages during high gradient duty cycle sequences. Theory and Methods A theoretical equation was derived to provide first- and second-order electrical fields induced at individual ECG electrodes as a function of gradient fields. Experiments were performed at 3T on healthy volunteers using a customized acquisition system that captured the full amplitude and frequency response of ECGs, or a commercial recording system. The 19 equation coefficients were derived via linear regression of data from accelerated sequences and were used to compute induced voltages in real-time during full resolution sequences to remove ECG artifacts. Restored traces were evaluated relative to ones acquired without imaging. Results Measured induced voltages were 0.7 V peak-to-peak during balanced steady state free precession (bSSFP) with the heart at the isocenter. Applying the equation during gradient echo sequencing, three-dimensional fast spin echo, and multislice bSSFP imaging restored nonsaturated traces and second-order concomitant terms showed larger contributions in electrodes further from the magnet isocenter. Equation coefficients are evaluated with high repeatability (ρ = 0.996) and are dependent on subject, sequence, and slice orientation. Conclusion Close agreement between theoretical and measured gradient-induced voltages allowed for real-time removal. Prospective estimation of sequence periods in which large induced voltages occur may allow hardware removal of these signals. Magn Reson Med, 2015. © 2015 Wiley Periodicals, Inc.

International audience; Non-invasive fetal electrocardiography (NI-FECG) is a promising alternative continuous fetal monitoring method that has the potential to allow morphological analysis of the FECG. However, there are a number of challenges associated with the evaluation of morphological parameters from the NI-FECG, including low signal to noise ratio of the NI-FECG and methodological challenges for getting reference annotations and evaluating the accuracy of segmentation algorithms. This work aims to validate the measurement of the fetal QT interval in term laboring women using a NI-FECG electrocardiogram monitor. Fetal electrocardiogram data were recorded from 22 laboring women at term using the NI-FECG and an invasive fetal scalp electrode simultaneously. A total of 105 one-minute epochs were selected for analysis. Three pediatric electrophysiologists independently annotated individual waveforms and averaged waveforms from each epoch. The intervals measured on the averaged cycles taken from the NI-FECG and the fetal scalp electrode showed a close agreement; the root mean square error between all corresponding averaged NI-FECG and fetal scalp electrode beats was 13.6 ms, which is lower than the lowest adult root mean square error of 16.1 ms observed in related adult QT studies. These results provide evidence that NI-FECG technology enables accurate extraction of the fetal QT interval.

Background An MRI-compatible 12-lead ECG platform, equipped with MRI-gradient induced-voltage removal hardware and magneto-hydrodynamic voltage removal software [1], was previously applied to physiological monitoring and synchronization of cardiac imaging of patients inside MRI. This approach had limited success for highduty-cycle [(total Gradient-ramp-time per R-R)/(R-R time) >20%] MRI sequences, such as Steady State Free Precession (SSFP), Short-TR Gradient Echo (GRE), and Short-TR Fast Spin Echo. The study objective is to measure and develop a method to remove gradient-induced voltages on 12-lead ECGs during high-duty-cycle MRI sequences.

Objective To validate the non-radiometric, broth-based ESP system for determining Mycobacterium avium complex (MAC) susceptibilities. Methods MAC isolates from sterile body sites of 20 adult HIV-infected patients who were failing their present MAC regimen were identified. Susceptibilities were determined and comparisons made between the agar proportion method and the ESP system for clarithromycin, ethambutol, sparfloxacin and cycloserine. Results Ninety-nine percent of the MICs generated by the ESP system were identical to or lower than the MICs determined by the agar proportion method. In vitro resistance was documented by the ESP system for 86% of the drugs that patients were taking at the time of breakthrough, and no resistance was seen to cycloserine, a drug that no patient was taking. Conclusions The ESP system, a fast and reliable method for determining MAC susceptibilities, could be used to optimize MAC regimens in a timely fashion, avoid the use of ineffective drugs, minimize emerging resistance and ultimately improve outcome.

Objective We sought to evaluate the accuracy of a novel system for measuring fetal heart rate (FHR) and ST-segment changes using noninvasive electrodes on the maternal abdomen. Study Design Fetal electrocardiograms were recorded using abdominal sensors from 32 term laboring women who had a fetal scalp electrode (FSE) placed for a clinical indication. Results Good-quality data for FHR estimation were available in 91.2% of the FSE segments and 89.9% of the abdominal electrode segments. The root mean square error between the FHR data calculated by both methods over all processed segments was 0.36 beats per minute. ST deviation from the isoelectric point ranged from 0–14.2% of R-wave amplitude. The root mean square error between the ST change calculated by both methods averaged over all processed segments was 3.2%. Conclusion FHR and ST change acquired from the maternal abdomen is highly accurate and, on average, is clinically indistinguishable from FHR and ST change calculated using FSE data.

A prospective study was undertaken to determine colonization rates, susceptibility profiles, and outcomes in patients with clinical isolates of Acinetobacter baumannii. Fifty percent of patients became colonized with A baumannii, and 29% of these patients had clinical and colonizing isolates with discordant susceptibility profiles, without apparent relation to antibiotic use. Barrier infection control measures are necessary to prevent nosocomial transmission.

Reported rates of nephrotoxicity associated with the systemic use of polymyxins have varied widely. The emergence of infections due to multiresistant gram-negative bacteria has necessitated the use of systemic polymyxin B once again for the treatment of such infections. We retrospectively investigated the rate of nephrotoxicity in patients receiving polymyxin B parenterally for the treatment of infections caused by multiresistant gram-negative bacteria from October 1999 to September 2000. Demographic and clinical information was obtained for 60 patients. Outcome measures of interest were renal toxicity and clinical and microbiologic efficacy. Renal failure developed in 14% of the patients, all of whom had normal baseline renal function. Development of renal failure was independent of the daily and cumulative doses of polymyxin B and the length of treatment but was significantly associated with older age (76 versus 59 years, P = 0.02). The overall mortality was 20%, but it increased to 57% in those who developed renal failure. The organism was cleared in 88% of the patients from whom repeat specimens were obtained. The use of polymyxin B to treat multiresistant gram-negative infections was highly effective and associated with a lower rate of nephrotoxicity than previously described.

Objective To evaluate the results of treating vancomycin-resistant Enterococcus faecium (VREF) bacteremia with chloramphenicol. Methods We retrospectively reviewed the charts of all adult patients with VREF bacteremia treated with chloramphenicol during the calendar year 1998 at a 522-bed tertiary referral center in New York City. Patients were identified by reviewing microbiology laboratory records. Patients with clinically significant VREF bacteremia who received chloramphenicol for at least 48 h were included in the study. Clinical and microbiological outcomes were determined. Microbiological and molecular tests were performed on a small representative sample of isolates to identify the presence of resistance mechanisms and to look for similarity among the isolates. Results Seven episodes of significant VREF bacteremia occurred in six patients. Mean age was 54 years. All patients had cancer and three had severe neutropenia. Five of seven episodes were associated with chronic indwelling devices, but in only one of these cases was the device removed. All isolates were susceptible to chloramphenicol in vitro. All six microbiologically evaluable episodes had a favorable response to chloramphenicol treatment, and four of seven (57%) clinically evaluable episodes had favorable outcomes. Only one death may have been due to VREF bacteremia, so the maximal attributable mortality was 14%. The three representative samples that were tested further were indistinguishable from one another and they displayed no evidence of resistance mechanisms. Conclusions In a cohort of severely ill cancer patients, chloramphenicol was effective in treating VREF bacteremia. The use of chloramphenicol should be considered in treating infections with this highly resistant organism, where therapeutic options are limited.

To identify characteristics associated with mortality in HIV-infected patients with bacteremia, 88 bacteremic episodes in 80 HIV-infected patients were prospectively identified over a 5-month period and observed for 30 days. Demographic, clinical, laboratory, and radiologic data were collected. Mean and median age was 41 years. Most study subjects were homosexual men. Median CD4 count was 20 cells/mm3. Gram-positive organisms predominated (65%). The most common source of bacteremia was intravascular catheters (45%). Overall mortality was 30%. A history of malignancy, three or more opportunistic infections, shock, low hemoglobin, source of bacteremia other than an intravascular catheter, resistance to therapy, and a second bacteremic episode during the study period, were all found to be independent predictors of mortality. In this cohort of HIV-infected patients, most of whom were severely immunosuppressed, several factors were found to be significantly and independently associated with mortality.

We report a case of prostate abscess due to Histoplasma capsulatum in a patient with the acquired immunodeficiency syndrome. The diagnosis and management are discussed, and the literature is reviewed.

The prevalence of vitamin A deficiency and its association with dietary retinol intake in patients with AIDS was assessed in a cross-sectional study. Sixty eligible patients with AIDS provided serum samples that were analyzed for retinol content. Exclusion criteria included current use of vitamin supplements (57% of the 140 willing to participate) and pregnancy (none). Past dietary intake was determined using a standardized food intake frequency questionnaire. The prevalence of hyporetinemia was 22%. This was a 241-fold greater prevalence than that of a representative sample of the U.S. population, after adjusting for age and sex. There was a positive association between serum retinol status and dietary intake, but 27% of those with adequate intake had serum retinol levels below the normal range. These findings suggest that regardless of intake, patients with AIDS may represent a population at considerable risk of vitamin A deficiency.

NAFCILLIN, 6-(2-ethoxy-1-naphthamido) penicillin,1 is one of the semisynthetic, penicillinase-resistant penicillins that has been introduced since the isolation of 6-aminopenicillanic acid.2 Each of the newer penicillins in this series — namely, oxacillin, diphenicillin and nafcillin — has several readily apparent advantages over methicillin,3 the first one to become available for clinical use. Most important of these advantages are acid stability, permitting absorption of the drug when it is administered orally, and greater in vitro activity against both penicillinase-producing and nonpenicillinase-producing staphylococci. In addition, some data suggest that nafcillin may have greater therapeutic activity than methicillin or oxacillin in experimental infections in . . .

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Two patients with the adult respiratory distress syndrome were found to have rising complement-fixation titers to Mycoplasma pneumoniae. This unusual presentation of Mycoplasma and its management are discussed. The need to consider M pneumoniae in a patient with the adult respiratory distress syndrome is emphasized.

The susceptibility of Bacteroides fragilis to the administration of clindamycin, and the efficacy of this agent in Bacteroides infections are well documented. Clindamycin-resistant strains of B. fragilis were isolated from two patients with bacteremia at two institutions. Clinically significant resistance to clindamycin therapy has not been noted previously in B. fragilis infections.

Of the anaerobic, nonsporulating, gram-negative bacilli, those of the genus Bacteroides are most frequently associated with serious infections in man. Forty clinical isolates of the species Bacteroides fragilis were tested quantitatively against 24 antibiotics by an agar-dilution method under anaerobic conditions. Clindamycin, the most active antibiotic studied, had a median MIC of 0.19 ng/ml. Rifampin, erythromcyin, lincomycin, and chloramphenicol also inhibited all isolates in clinically attainable concentrations. More than half of the strains tested were resistant to tetracycline. Some isolates were susceptible to penicillin G, ampicillin, carbenicillin, and the cephalosporins, and all were resistant to the aminoglycosides, polymyxins, and semisynthetic penicillinase-resistant penicillins. The genus Bacteroides consists of nonsporulating, gram-negative bacilli which are obligate anaerobes. These organisms predominate numerically in the normal bacterial flora of the large bowel and are important components of the normal flora of the oral cavity and the urogenital tract [1]. Although they have long been recognized as significant human pathogens, the literature on infec