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We assessed the impact of personal protective equipment (PPE) doffing errors on healthcare worker (HCW) contamination with multidrug-resistant organisms (MDROs).
Prospective, observational study.
The study was conducted at 4 adult ICUs at 1 tertiary-care teaching hospital.
HCWs who cared for patients on contact precautions for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci, or multidrug-resistant gram-negative bacilli were enrolled. Samples were collected from standardized areas of patient body, garb sites, and high-touch environmental surfaces in patient rooms. HCW hands, gloves, PPE, and equipment were sampled before and after patient interaction. Research personnel observed PPE doffing and coded errors based on CDC guidelines.
We enrolled 125 HCWs; most were nurses (66.4%) or physicians (19.2%). During the study, 95 patients were on contact precautions for MRSA. Among 5,093 cultured sites (HCW, patient, environment), 652 (14.7%) yielded the target MDRO. Moreover, 45 HCWs (36%) were contaminated with the target MDRO after patient interactions, including 4 (3.2%) on hands and 38 (30.4%) on PPE. Overall, 49 HCWs (39.2%) made multiple doffing errors and were more likely to have contaminated clothes following a patient interaction (risk ratio [RR], 4.69; P = .04). All 4 HCWs with hand contamination made doffing errors. The risk of hand contamination was higher when gloves were removed before gowns during PPE doffing (RR, 11.76; P = .025).
When caring for patients on CP for MDROs, HCWs appear to have differential risk for hand contamination based on their method of doffing PPE. An intervention as simple as reinforcing the preferred order of doffing may reduce HCW contamination with MDROs.
We compared sepsis “time zero” and Centers for Medicare and Medicaid Services (CMS) SEP-1 pass rates among 3 abstractors in 3 hospitals. Abstractors agreed on time zero in 29 of 80 (36%) cases. Perceived pass rates ranged from 9 of 80 cases (11%) to 19 of 80 cases (23%). Variability in time zero and perceived pass rates limits the utility of SEP-1 for measuring quality.
We investigated the clinical predictors of methicillin-resistance and their impact on mortality in 371 patients with Staphylococcus aureus bacteraemia identified from two prospective multi-centre studies. Methicillin resistant S. aureus (MRSA) accounted for 42.2% of community-onset and 74.5% of hospital-onset cases. No significant clinical difference was found between patients infected with MRSA vs. methicillin-sensitive S. aureus (MSSA), except that the former were more likely to have had hospital-onset bacteraemia and received antibiotics in the preceding 90 days. After stratifying according to the acquisition site, prior antibiotic use was the only independent predictor of having MRSA in both community-onset and hospital-onset cases. The frequency of inappropriate empirical antibiotic therapy was higher in patients with MRSA than in those with MSSA bacteraemia. However, methicillin resistance was not a predictor of mortality in patients and the clinical characteristics and outcomes of both MRSA and MSSA bacteraemia were similar. This study indicates that there are no definitive clinical or epidemiological risk factors which could distinguish MRSA from MSSA cases with the exception of the previous use of antibiotics for having MRSA bacteraemia, which emphasises the prudent use of glycopeptide treatment of patients at risk for invasive MRSA infections.
Bathing intensive care unit (ICU) patients with 2% chlorhexidine gluconate (CHG)–impregnated cloths decreases the risk of healthcare-associated bacteremia and multidrug-resistant organism transmission. Hospitals employ different methods of CHG bathing, and few studies have evaluated whether those methods yield comparable results.
To determine whether 3 different CHG skin cleansing methods yield similar residual CHG concentrations and bacterial densities on skin.
Prospective, randomized 2-center study with blinded assessment.
PARTICIPANTS AND SETTING
Healthcare personnel in surgical ICUs at 2 tertiary-care teaching hospitals in Chicago, Illinois, and Boston, Massachusetts, from July 2015 to January 2016.
Cleansing skin of one forearm with no-rinse 2% CHG-impregnated polyester cloth (method A) versus 4% CHG liquid cleansing with rinsing on the contralateral arm, applied with either non–antiseptic-impregnated cellulose/polyester cloth (method B) or cotton washcloth dampened with sterile water (method C).
In total, 63 participants (126 forearms) received method A on 1 forearm (n=63). On the contralateral forearm, 33 participants received method B and 30 participants received method C. Immediately and 6 hours after cleansing, method A yielded the highest residual CHG concentrations (2500 µg/mL and 1250 µg/mL, respectively) and lowest bacterial densities compared to methods B or C (P<.001).
In healthy volunteers, cleansing with 2% CHG-impregnated cloths yielded higher residual CHG concentrations and lower bacterial densities than cleansing with 4% CHG liquid applied with either of 2 different cloth types and followed by rinsing. The relevance of these differences to clinical outcomes remains to be determined.
We present first results from pilot observations using a phased array feed (PAF) mounted on the Parkes 64-m radio telescope. The observations presented here cover a frequency range from 1 150 to 1 480 MHz and are used to show the ability of PAFs to suppress standing wave problems by a factor of ~10, which afflict normal feeds. We also compare our results with previous HIPASS observations and with previous H i images of the Large Magellanic Cloud. Drift scan observations of the GAMA G23 field resulted in direct H i detections at z = 0.0043 and z = 0.0055 of HIPASS galaxies J2242-30 and J2309-30. Our new measurements generally agree with archival data in spectral shape and flux density, with small differences being due to differing beam patterns. We also detect signal in the stacked H i data of 1 094 individually undetected galaxies in the GAMA G23 field in the redshift range 0.05 ⩽ z ⩽ 0.075. Finally, we use the low standing wave ripple and wide bandwidth of the PAF to set a 3σ upper limit to any positronium recombination line emission from the Galactic Centre of <0.09 K, corresponding to a recombination rate of <3.0 × 1045 s−1.
It is unclear which of four popular contemporary diet patterns is best for weight maintenance among postmenopausal women. Four dietary patterns were characterised among postmenopausal women aged 49–81 years (mean 63·6 (sd 7·4) years) from the Women’s Health Initiative Observational Study: (1) a low-fat diet; (2) a reduced-carbohydrate diet; (3) a Mediterranean-style (Med) diet; and (4) a diet consistent with the US Department of Agriculture’s Dietary Guidelines for Americans (DGA). Discrete-time hazards models were used to compare the risk of weight gain (≥10 %) among high adherers of each diet pattern. In adjusted models, the reduced-carbohydrate diet was inversely related to weight gain (OR 0·71; 95 % CI 0·66, 0·76), whereas the low-fat (OR 1·43; 95 % CI 1·33, 1·54) and DGA (OR 1·24; 95 % CI 1·15, 1·33) diets were associated with increased risk of weight gain. By baseline weight status, the reduced-carbohydrate diet was inversely related to weight gain among women who were normal weight (OR 0·72; 95 % CI 0·63, 0·81), overweight (OR 0·67; 95 % CI 0·59, 0·76) or obese class I (OR 0·63; 95 % CI 0·53, 0·76) at baseline. The low-fat diet was associated with increased risk of weight gain in women who were normal weight (OR 1·28; 95 % CI 1·13, 1·46), overweight (OR 1·60; 95 % CI 1·40, 1·83), obese class I (OR 1·73; 95 % CI 1·43, 2·09) or obese class II (OR 1·44; 95 % CI 1·08, 1·92) at baseline. These findings suggest that a low-fat diet may promote weight gain, whereas a reduced-carbohydrate diet may decrease risk of postmenopausal weight gain.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
Solar radiation pressure can cause rotational bursting and eventual elimination from the solar system of small asymmetric interplanetary particles by a windmill effect. The life span determined by this process for stony meteoritic material or tektite glass with radii of 1 cm is on the order of 105 years. Same size material which contains iron, nickel or aluminum, with properties such that it is subject to 5 percent of the amount of spin damping as pure metals, can be removed from the solar system on the order of 106 years by this process. Ordinary chondritic material, despite its high resistivity, is subject to a type of magnetic spin damping, in addition to the normal spin damping, with the consequent result that this type material cannot be removed from the solar system by this process. This depletion mechanism appears to work faster than the traditional Poynting-Robertson effect by approximately two orders of magnitude for the nonmetallic particles and one order of magnitude for the metallic particles.
NASA’s Space Interferometry Mission (SIM), scheduled for launch in 2009, will determine the positions of thousands of stars as faint as V = 20 to a precision better than 4 microarcseconds (µas). A key part of the mission is the Astrometric Grid, which is a reference frame of several thousand stars with V ≤ 13 against which all relative measurements will be calibrated. To serve as a reliable inertial reference frame, the Grid must be astrometrically stable against photocenter jitter (from planets, binary companions, flaring or spotting) at the ~ 4µas level. Sub–solar metallicity giant stars, by virtue of their intrinsic luminosity, can probe the Galaxy to greater distances than almost any other stellar type at the same apparent magnitude. Thus, distant (> 3 kpc) giants with V < 13 will have proportionately smaller astrometric jitter compared to other potential Astrometric Grid star candidates. The Grid Giant Star Survey is a patchwork all-sky survey to find sub–solar metallicity K giants for the Grid, and to provide a unique database for studies of Galactic stellar populations. We describe here the survey characteristics and give examples of results to date.
Methicillin-resistant Staphylococcus aureus (MRSA) infections due to USA300 have become widespread in community and healthcare settings. It is unclear whether risk factors for bloodstream infections (BSIs) differ by strain type.
To examine the epidemiology of S. aureus BSIs, including USA300 and non-USA300 MRSA strains.
Retrospective observational study with molecular analysis.
Large urban public hospital.
Individuals with S. aureus BSIs from January 1, 2007 through December 31, 2013.
We used electronic surveillance data to identify cases of S. aureus BSI. Available MRSA isolates were analyzed by pulsed-field gel electrophoresis. Poisson regression was used to evaluate changes in BSI incidence over time. Risk factor data were collected by medical chart review and logistic regression was used for multivariate analysis of risk factors.
A total of 1,015 cases of S. aureus BSIs were identified during the study period; 36% were due to MRSA. The incidence of hospital-onset (HO) MRSA BSIs decreased while that of community-onset (CO) MRSA BSIs remained stable. The rate of CO– and HO– methicillin-susceptible S. aureus infections both decreased over time. More than half of HO-MRSA BSIs were due to the USA300 strain type and for 4 years, the proportion of HO-MRSA BSIs due to USA300 exceeded 60%. On multivariate analysis, current or former drug use was the only epidemiologic risk factor for CO- or HO-MRSA BSIs due to USA300 strains.
USA300 MRSA is endemic in communities and hospitals and certain populations (eg, those who use illicit drugs) may benefit from enhanced prevention efforts in the community.
Infect. Control Hosp. Epidemiol. 2015;36(12):1417–1422
The Yang-Baxter-like matrix equation AXA = XAX is reconsidered, where A is any complex square matrix. A collection of spectral solutions for the unknown square matrix X were previously found. When A is diagonalisable, by applying the mean ergodic theorem we propose numerical methods to calculate those solutions.
This paper examines the role of local attitudes toward gambling on corporate innovative activity. Using a county’s Catholics-to-Protestants ratio as a proxy for local gambling preferences, we find that firms located in gambling-prone areas tend to undertake riskier projects, spend more on innovation, and experience greater innovative output. We contrast the local gambling effect with chief executive officer (CEO) overconfidence, another behavioral effect reported to influence innovation. We find that local gambling preferences are a stronger determinant of innovative activity, with CEO overconfidence being more relevant to innovation in areas where gambling attitudes are strong.
Adjustment for body weight and physical activity has been suggested as an alternative to adjusting for reported energy intake in nutritional epidemiology. We examined which of these approaches would yield stronger correlations between nutrients and their biomarkers.
A cross-sectional study in which dietary fatty acids, carotenoids and retinol were adjusted for reported energy intake and, separately, for weight and physical activity using the residual method. Correlations between adjusted nutrients and their biomarkers were examined.
Cases and controls from a nested case–control study of erythrocyte fatty acids and CHD (n 442) and of plasma carotenoids and retinol and breast cancer (n 1254).
Correlations between intakes and plasma levels of trans-fatty acids were 0·30 (energy-adjusted) and 0·16 (weight- and activity-adjusted); for erythrocyte levels, the corresponding correlations were 0·37 and 0·25. Energy-adjusted intakes of linoleic acid and α-linolenic acid were more strongly correlated with their respective biomarkers than weight- and activity-adjusted intakes, but the differences were not significant except for linoleic acid (erythrocyte). Weight- and activity-adjusted DHA intake was slightly more strongly correlated with its plasma biomarker than energy-adjusted intake (0·37 v. 0·34). Neither method made a difference for DHA (erythrocyte), carotenoids and retinol.
The effect of energy adjustment depends on the nutrient under investigation, and adjustment for energy calculated from the same questionnaire used to estimate nutrient intakes improves the correlation of some nutrients with their biomarkers appreciably. For the nutrients examined, adjustment using weight and physical activity had at most a small effect on these correlations.
To assess how healthcare professionals caring for patients in intensive care units (ICUs) understand and use antimicrobial susceptibility testing (AST) for multidrug-resistant gram-negative bacilli (MDR-GNB).
A knowledge, attitude, and practice survey assessed ICU clinicians' knowledge of antimicrobial resistance, confidence interpreting AST results, and beliefs regarding the impact of AST on patient outcomes.
Sixteen ICUs affiliated with NewYork-Presbyterian Hospital.
Attending physicians and subspecialty residents with primary clinical responsibilities in adult or pediatric ICUs as well as infectious diseases subspecialists and clinical pharmacists.
Participants completed an anonymous electronic survey. Responses included 4-level Likert scales dichotomized for analysis. Multivariate analyses were performed using generalized estimating equation logistic regression to account for correlation of respondents from the same ICU.
The response rate was 51% (178 of 349 eligible participants); of the respondents, 120 (67%) were ICU physicians. Those caring for adult patients were more knowledgeable about antimicrobial activity and were more familiar with MDR-GNB infections. Only 33% and 12% of ICU physicians were familiar with standardized and specialized AST methods, respectively, but more than 95% believed that AST improved patient outcomes. After adjustment for demographic and healthcare provider characteristics, those familiar with treatment of MDR-GNB bloodstream infections, those aware of resistance mechanisms, and those aware of AST methods were more confident that they could interpret AST results and/or request additional in vitro testing.
Our study uncovered knowledge gaps and educational needs that could serve as the foundation for future interventions. Familiarity with MDR-GNB increased overall knowledge, and familiarity with AST increased confidence interpreting the results.
If A is a nonsingular matrix such that its inverse is a stochastic matrix, the classic Brouwer fixed point theorem implies that the matrix equation AXA = XAX has a nontrivial solution. An explicit expression of this nontrivial solution is found via the mean ergodic theorem, and fixed point iteration is considered to find a nontrivial solution.
Increasing trends in the consumption of commercial sugar-sweetened beverages (SSB) have occurred in parallel with rising levels of obesity in Latin America, but data showing the relationship between these SSB and obesity are limited. The current study examined the association between commercial and traditional SSB and measures of adiposity in Costa Rica.
A cross-sectional analysis was conducted in which the exposure, SSB intake, was defined as frequency of daily servings of ‘fresco’ (a traditional home-made beverage), fruit drink (commercially available SSB), soda and fruit juice (made from fruits at home). Multivariate linear regression was used to estimate associations between SSB intake and BMI, waist-to-hip ratio and skinfold thickness.
Central Valley, Costa Rica.
Controls (n 2045) of a case–control study on diet and heart disease in Costa Rica.
Fresco, fruit drink, soda and fruit juice were consumed ≥1 time/d by 47 %, 14 %, 4 % and 14 % of the population, respectively. One serving/d of soda, fruit drink and fresco was associated with 0·89, 0·49 and 0·21 kg/m2 higher BMI, respectively (all P < 0·05). Fruit drink (≥1 serving/d) was associated with higher waist-to-hip ratio (P = 0·004), while soda and fresco were associated with higher skinfold thickness (P = 0·02 and 0·01, respectively). Associations with fruit juice intake were modest and not statistically significant. Other factors associated with higher BMI were higher income and less education, smoking and physical inactivity (all P < 0·05).
Increasing intake of commercially available SSB could be in part responsible for the high prevalence of obesity among Hispanic adults.
We present results from a study of the vibrational, structural, and electronic properties of C60 powder and thin films. Raman spectroscopy and diamond anvil cell have been used to study pressure dependence of the Raman active modes of C60 powder. The material undergoes structural phase transition between 9 and 15 GPa. Some of the Raman modes soften, while others harden with increasing pressure. Thin films of C60 and La-doped C60 have also been studied by using Raman scattering, x-ray diffraction, x-ray photoelectron spectroscopy and uv photoemission spectroscopy. Whereas the powder and La-doped C60 films exhibit fcc crystalline structure, the C60 film appears disordered. Further, we observe a significant difference in the electronic valence bands of the doped and undoped films.