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The main risk factor for acquisition of antimicrobial-resistant bacteria (ARB) is antimicrobial exposure, although acquisition can occur in their absence. The aim of this study was to quantify the proportion of patients who acquire ARB without antimicrobial exposure.
We searched Medline, Embase, and the Cochrane library for publications between January 1, 2000, and July 24, 2017, to identify studies of ARB acquisition in endemic settings. Studies required collection of serial surveillance cultures with acquisition defined as a negative baseline culture and a subsequent positive culture for an ARB, including either multidrug-resistant gram-negative bacteria or antimicrobial-resistant enterococci. Intervention studies were excluded. For each study, the proportion of patients who acquired an ARB but were not exposed to antimicrobials during the study period was quantified.
A total of 4,233 citations were identified; 147 underwent full-text review. Of these, 10 studies met inclusion criteria; 7 studies were considered to be at low risk of bias; and 6 studies were conducted in the intensive care unit (ICU) setting. The overall summary estimate for the proportion of patients who were not exposed to antimicrobials among those who acquired an ARB was 16.6% (95% CI, 7.8%–31.8%; P < .001), ranging from 0% to 57.1%. We observed no heterogeneity in the ICU studies but high heterogeneity among the non-ICU studies.
In most included studies, a subset of patients acquired an ARB but were not exposed to antimicrobials. Future studies need to address transmission dynamics of ARB acquisition in the absence of antimicrobials.
A theoretically based relationship for the Darcy–Weisbach friction factor
for rough-bed open-channel flows is derived and discussed. The derivation procedure is based on the double averaging (in time and space) of the Navier–Stokes equation followed by repeated integration across the flow. The obtained relationship explicitly shows that the friction factor can be split into at least five additive components, due to: (i) viscous stress; (ii) turbulent stress; (iii) dispersive stress (which in turn can be subdivided into two parts, due to bed roughness and secondary currents); (iv) flow unsteadiness and non-uniformity; and (v) spatial heterogeneity of fluid stresses in a bed-parallel plane. These constitutive components account for the roughness geometry effect and highlight the significance of the turbulent and dispersive stresses in the near-bed region where their values are largest. To explore the potential of the proposed relationship, an extensive data set has been assembled by employing specially designed large-eddy simulations and laboratory experiments for a wide range of Reynolds numbers. Flows over self-affine rough boundaries, which are representative of natural and man-made surfaces, are considered. The data analysis focuses on the effects of roughness geometry (i.e. spectral slope in the bed elevation spectra), relative submergence of roughness elements and flow and roughness Reynolds numbers, all of which are found to be substantial. It is revealed that at sufficiently high Reynolds numbers the roughness-induced and secondary-currents-induced dispersive stresses may play significant roles in generating bed friction, complementing the dominant turbulent stress contribution.
Introduction: Prompt defibrillation is critical during paediatric cardiac arrest. The main objective of this systematic review was to determine the initial defibrillation energy dose for ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT) that is associated with sustained return of spontaneous circulation (ROSC) during paediatric cardiac arrest. Associations between initial defibrillation energy dose with any ROSC, survival and defibrillation-induced complications were also assessed. Methods: A systematic review was performed using four databases (Medline, Embase, Web of Science, Cochrane Library) (PROSPERO: CRD42016036734). Human studies (cohort studies or controlled trials) and animal model studies (controlled trials) of pediatric cardiac arrest involving assessment of external defibrillation energy dosing were considered. The primary outcome was sustained ROSC. Two researchers independently reviewed all the titles and abstracts of the retrieved citations, selected the studies and extracted the data using a standardized template. Risk of bias of human non-randomised studies were assessed using the ROBIN-I tool (formerly ACROBAT-NRSI) tool proposed by the Cochrane Collaboration group. Results: The search strategy identified 14,471 citations of which 232 manuscripts were reviewed. Ten human and 10 animal model studies met the inclusion criteria. Human studies were prospective (n = 6) or retrospective (n = 4) cohort studies and included between 11 and 266 patients (median = 46 patients). Sustained ROSC rates ranged from 0 to 61% (n = 7). No studies reported a statistically significant association between the initial defibrillation energy dose and the rate of sustained ROSC (n = 7) or survival (n = 6). No human studies reported defibrillation-induced complications. Meta-analysis was not considered appropriate due to clinical heterogeneity. The overall risk of bias was moderate. All animal studies were randomized controlled trials with 8 and 52 (median = 27) piglets. ROSC was frequently achieved (more than 85%) with energy dose ranging from 2 to 7 joules/kg (n = 7). The defibrillation threshold varied according to the body weight and appears to be higher in infant models. Conclusion: Defibrillation energy doses and thresholds varied according to the body weight and trended higher for infants. No definitive association between initial defibrillation doses and the outcomes of sustained ROSC or survival could be demonstrated.
Introduction: This systematic scoping review aims to synthetize the available evidence on the epidemiology, risk factors, clinical characteristics, screening tools, prevention strategies, interventions and knowledge of health care providers regarding elder abuse in the emergency department (ED). Methods: A systematic literature search was performed using three databases (Medline, Embase and Cochrane Library). Grey literature was scrutinized. Studies were considered eligible when they were observational studies or randomized control trials reporting on elder abuse in the prehospital and/or ED setting. Data extraction was performed independently by two researchers and a qualitative approach was used to synthetize the findings. Results: A total of 443 citations were retrieved from which 58 studies published between 1988 and 2018 were finally included. Prevalence of elder abuse following an ED visit varied between 0.01% and 0.03%. Reporting of elder abuse to proper law authorities by ED physicians varied between 2% to 50% of suspected cases. The most common reported type of elder abuse detected was neglect followed by physical abuse. Female gender was the most consistent factor associated with elder abuse. Cognitive impairment, behavioral problems and psychiatric disorder of the patient or the caregiver were also associated with physical abuse and neglect as well as more frequent ED consultations. Several screening tools have been proposed, but ED-based validation is lacking. Literature on prehospital- or ED-initiated prevention and interventions was scarce without any controlled trial. Health care providers were poorly trained to detect and care for older adults who are suspected of being a victim of elder abuse. Conclusion: Elder abuse in the ED is an understudied topic. It remains underrecognized and underreported with ED prevalence rates lower than those in community-dwelling older adults. Health care providers reported lacking appropriate training and knowledge with regards to elder abuse. Dedicated ED studies are required.
Speleothem organic matter can be a powerful tracer for past environmental conditions and karst processes. Carbon isotope measurements (δ13C and 14C) in particular can provide crucial information on the provenance and age of speleothem organic matter, but are challenging due to low concentrations of organic matter in stalagmites. Here, we present a method development study on extraction and isotopic characterization of speleothem organic matter using a rapid procedure with low laboratory contamination risk. An extensive blank assessment allowed us to quantify possible sources of contamination through the entire method. Although blank contamination is consistently low (1.7 ± 0.34 – 4.3 ± 0.86 μg C for the entire procedure), incomplete sample decarbonation poses a still unresolved problem of the method, but can be detected when considering both δ13C and 14C values. We test the method on five stalagmites, showing reproducible results on samples as small as 7 μg C for δ13C and 20 μg C for 14C. Furthermore, we find consistently lower non-purgeable organic carbon (NPOC) 14C values compared to the carbonate 14C over the bomb spike interval in two stalagmites from Yok Balum Cave, Belize, suggesting overprint of a pre-aged or even fossil source of carbon on the organic fraction incorporated by these stalagmites.
Spectroscopic data from a var iety of analyt ical techniques such as x-ray diffraction (XRD), infrared (IR) and Raman spectroscopies, secondary ion mass spectrometry (SIMS) and energy dispersive X-ray analysis (EDX) can be obtained from small areas of samples (< 1 mm2) through the use of microscope sampling accessories. If provisions are made to scan or translate the sample, then a spectrum that is characteristic of each region of interest can be obtained. Alternatively, selective area detectors eliminate the requirement for scanning the sample. Extract ion of information about a specific energy band from each spectrum allows elucidat ion of the spatial distribution of the feature giving rise to that band. For example, the distribution of a compound could be imaged by extracting the intensity of an IR band or XRD peak due to that compound. Peak posit ion and peak width are other parameters that can be extracted as a function of posit ion. Similarly, elemental distributions could be obtained using SIMS and EDX.
We know little about the retirement plans of adults with chronic diseases. This research recruited Canadian workers 50–67 years of age from a national panel of 80,000 individuals (arthritis, n = 631; diabetes, n = 286; both arthritis and diabetes, n = 111; no chronic disabling conditions, n = 538). A cross-sectional survey asked participants about their expected age of retirement, future work plans, whether they were retiring sooner than planned, and bridged retirement. Chi-square analyses, analyses of variance, and regression analyses examined expectations and factors associated with them. Despite health difficulties, workers with arthritis and diabetes had retirement plans similar to those of healthy controls and consistent with normative expectations of working to a traditional retirement age. However, more respondents with arthritis or diabetes reported bridged retirement than healthy controls. Contrary to predictions, health factors accounted for less of the variance in retirement expectations than other factors. These findings point to the complexity surrounding retirement expectations and highlight person–job fit rather than disease factors alone.
The fluctuating drag forces acting on spherical roughness elements comprising the bed of an open-channel flow have been recorded along with synchronous measurements of the surrounding velocity field using stereoscopic particle image velocimetry. The protrusion of the target particle, equipped with a force sensor, was systematically varied between zero and one-half diameter relative to the hexagonally packed adjacent spheres. Premultiplied spectra of drag force fluctuations were found to have bimodal shapes with a low-frequency (
) peak corresponding to the presence of very-large-scale motions (VLSMs) in the turbulent flow. The high-frequency (
) region of the drag force spectra cannot be explained by velocity time series extracted from points around the particle, but instead appears to be dominated by the action of pressure gradients in the overlying flow field. For small particle protrusions, this high-frequency region contributes a majority of the drag force variance, while the relative importance of the low-frequency drag force fluctuations increases with increasing protrusion. The amplitude of high-frequency drag force fluctuations is modulated by the VLSMs irrespective of particle protrusion. These results provide some insight into the mechanics of bed particle stability and indicate that the optimum conditions for particle entrainment may occur when a low-pressure region embedded in the high-velocity portion of a VLSM overlays a particle.
Significant ethnic and socio-economic disparities exist in infectious diseases (IDs) rates in New Zealand, so accurate measures of these characteristics are required. This study compared methods of ascribing ethnicity and socio-economic status. Children in the Growing Up in New Zealand longitudinal cohort were ascribed to self-prioritised, total response and single-combined ethnic groups. Socio-economic status was measured using household income, and both census-derived and survey-derived deprivation indices. Rates of ID hospitalisation were compared using linked administrative data. Self-prioritised ethnicity was simplest to use. Total response accounted for mixed ethnicity and allowed overlap between groups. Single-combined ethnicity required aggregation of small groups to maintain power but offered greater detail. Regardless of the method used, Māori and Pacific children, and children in the most socio-economically deprived households had a greater risk of ID hospitalisation. Risk differences between self-prioritised and total response methods were not significant for Māori and Pacific children but single-combined ethnicity revealed a diversity of risk within these groups. Household income was affected by non-random missing data. The census-derived deprivation index offered a high level of completeness with some risk of multicollinearity and concerns regarding the ecological fallacy. The survey-derived index required extra questions but was acceptable to participants and provided individualised data. Based on these results, the use of single-combined ethnicity and an individualised survey-derived index of deprivation are recommended where sample size and data structure allow it.
Keto analogues and amino acids (KAAA) supplementation can reduce blood ammonia concentrations in athletes undergoing high-intensity exercise under both ketogenic and thermoneutral conditions. This study evaluated the acute effects of KAAA supplementation on ammonia metabolism during extenuating endurance exercise in rats fed a ketogenic diet. In all, eighty male Fischer rats at 90 d of age were divided into eight groups, and some were trained using a swimming endurance protocol. A ketogenic diet supplemented with keto analogues was administered for 10 d. Administration of the ketogenic diet ended 3 d before the exhaustion test (extenuating endurance exercise). A ketogenic diet plus KAAA supplementation and extenuating endurance exercise (trained ketogenic diet supplemented with KAAA (TKKa)) increased blood ammonia concentrations by approximately 50 % compared with the control diet (trained control diet supplemented with KAAA (TCKa)) and similar training (effect size=1·33; statistical power=0·50). The KAAA supplementation reduced blood urea concentrations by 4 and 18 % in the control and ketogenic diet groups, respectively, compared with the groups fed the same diets without supplementation. The trained groups had 60 % lower blood urate concentrations after TCKa treatment than after TKKa treatment. Our results suggest that KAAA supplementation can reduce blood ammonia concentrations after extenuating endurance exercise in rats fed a balanced diet but not in rats fed a ketogenic diet.
We use a random utility model for birding destination choices based on the reports of Oregon and Washington State members of the Cornell University Laboratory of Ornithology eBird citizen science project. We estimate spatially differentiated welfare effects that birders may experience as a consequence of forecasted changes in land cover and climate. We predict per-trip welfare effects (equivalent variations) expected under a business-as-usual scenario using published forecasts for both land cover and species richness. We find significant county-level heterogeneity across eBirders in predicted average per-trip welfare effects. The results suggest discernible distributional consequences across active birders in different areas.
Vanadium Oxide has application to infrared bolometers due to high temperature coefficient of resistivity (TCR). It has attracted interest for switchable plasmonic devices due to its metal to insulator transition near room temperature. We report here the properties of vanadium oxide deposited by an aqueous spray process. The films have a ropy surface morphology with ∼70 nm surface roughness. The polycrystalline phase depends on annealing conditions. The films have TCR of ∼2%/deg, which compares well with sputtered films. Only weak evidence is found for an insulator-metal phase transition in these films.
OBJECTIVES/SPECIFIC AIMS: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) skin and soft tissue infections (SSTIs) recurrence ranges from 16% to 43% and presents significant challenges to clinicians, patients, and families. This comparative effectiveness research study aims to disseminate, implement and evaluate whether an existing intervention, consisting of decolonization and decontamination procedures, which has been determined to be effective in hospital intensive care unit settings, can be implemented by Community Health Workers (CHWs) or “promotoras” conducting home visits prevent recurrence of CA-MRSA and transmission within their households for patients presenting to primary care with SSTIs. METHODS/STUDY POPULATION: In partnership with 3 Community Health Centers and 4 community hospitals in NYC, this study will recruit patients (n=278) with confirmed MRSA SSTIs and their household members. Participants are randomized to receive either a CHW/Promotora-delivered decolonization-decontamination intervention or usual care, which includes hygiene education. The highly engaged stakeholder team meets monthly to review interim results, identify areas for refinement and new research questions, and develop and implement strategies to improve participant engagement and retention. RESULTS/ANTICIPATED RESULTS: MRSA and MSSA were found in 19% and 21.1% of wound cultures, respectively. 59.5% with MRSA+ wound culture had one or more MRSA+ surveillance culture; 67.8% with MSSA+ wound culture had one or more MSSA+ surveillance culture. The “warm handoff” approach, developed and implemented by the stakeholder team to engage patients from their initial consent to return of lab results and scheduling of the home visits, helped improve completion of baseline home visits by 14%, from 45% to 59% of eligible participants. Home visits have demonstrated that 60% of households had at least one surface contaminated with S. aureus. Of the surfaces that tested positive in the households, nearly 20% were MRSA and 81% were MSSA; 32.5% of household members had at least one surveillance culture positive for S. aureus (MRSA: 7.7%, MSSA: 92.3%). DISCUSSION/SIGNIFICANCE OF IMPACT: This study aims to understand the systems-level, patient-level, and environmental-level factors associated with SSTI recurrence and household transmission, and to examine the interactions between bacterial genotypic and clinical/phenotypic factors on decontamination, decolonization, SSTI recurrence and household transmission. This study will evaluate the barriers and facilitators of implementation of home visits by CHWs in underserved populations, and aims to strengthen the weak evidence base for implementation of strategies to reduce SSTI recurrence and household transmission.
OBJECTIVES/SPECIFIC AIMS: Neurological injury remains as the main limiting factor for overall recovery after cardiac arrest (CA). Currently available indicators of neurological injury are inadequate for early prognostication after return of spontaneous circulation (ROSC). High diversification of brain mitochondrial cardiolipins (CL) makes them unique candidates to quantify brain injury and to predict prognosis early after ROSC. METHODS/STUDY POPULATION: CL content in plasma in 39 patients within 6 hours of ROSC and 10 healthy subjects as well as CL content in human heart and brain specimens were quantified using a high-resolution liquid chromatography mass spectrometry method. The quantities of brain-type CL species were correlated with clinical parameters of brain injury severity permitting derivation of a cerebral CL score (C-score) using linear regression. C-score and a single CL species (70:5) were evaluated in patients with varying neurological injury and outcome. Using a rat model of CA, CL was quantified in the plasma and brain of rats using similar methods and results compared with the controls. RESULTS/ANTICIPATED RESULTS: We found that brain and the heart fell on extreme ends of the CL diversity spectrum with 26 species of CL exclusively present in human brain not heart. Nine of these 26 species were present in plasma within 6 hours of ROSC with quantities correlating with greater brain injury. The C-score correlated with early neurologic injury and predicted discharge neurologic/functional outcome. CL (70:5) emerged as a potential point-of-care marker that alone was predictive of injury severity and outcome nearly as well as C-score. Using a rat CA model we showed a significant reduction in hippocampal CL content corresponding to CL released from the brain into systemic circulation. C-score was significantly increased in 10 minute Versus 5 minute no-flow CA and naïve controls. DISCUSSION/SIGNIFICANCE OF IMPACT: CA results in appearance and accumulation of CL in plasma, proportional to injury severity. Quantitation of brain-type CL species in plasma can be used to prognosticate neurological injury within 6 hours after ROSC.