Emergence of chaotic scattering in ultracold Er and Dy

We show that for ultracold magnetic lanthanide atoms chaotic scattering emerges due to a combination of anisotropic interaction potentials and Zeeman coupling under an external magnetic field. This scattering is studied in a collaborative experimental and theoretical effort for both dysprosium and erbium. We present extensive atom-loss measurements of their dense magnetic Feshbach resonance spectra, analyze their statistical properties, and compare to predictions from a random-matrix-theory inspired model. Furthermore, theoretical coupled-channels simulations of the anisotropic molecular Hamiltonian at zero magnetic field show that weakly-bound, near threshold diatomic levels form overlapping, uncoupled chaotic series that when combined are randomly distributed. The Zeeman interaction shifts and couples these levels, leading to a Feshbach spectrum of zero-energy bound states with nearest-neighbor spacings that changes from randomly to chaotically distributed for increasing magnetic field. Finally, we show that the extreme temperature sensitivity of a small, but sizeable fraction of the resonances in the Dy and Er atom-loss spectra is due to resonant non-zero partial-wave collisions. Our threshold analysis for these resonances indicates a large collision-energy dependence of the three-body recombination rate

Variability in testing policies and impact on reported Clostridium difficile infection rates: results from the pilot Longitudinal European Clostridium difficile Infection Diagnosis surveillance study (LuCID)

Lack of standardised Clostridium difficile testing is a potential confounder when comparing infection rates. We used an observational, systematic, prospective large-scale sampling approach to investigate variability in C. difficile sampling to understand C. difficile infection (CDI) incidence rates. In-patient and institutional data were gathered from 60 European hospitals (across three countries). Testing methodology, testing/CDI rates and case profiles were compared between countries and institution types. The mean annual CDI rate per hospital was lowest in the UK and highest in Italy (1.5 vs. 4.7 cases/10,000 patient bed days [pbds], p < 0.001). The testing rate was highest in the UK compared with Italy and France (50.7/10,000 pbds vs. 31.5 and 30.3, respectively, p < 0.001). Only 58.4 % of diarrhoeal samples were tested for CDI across all countries. Overall, only 64 % of hospitals used recommended testing algorithms for laboratory testing. Small hospitals were significantly more likely to use standalone toxin tests (SATTs). There was an inverse correlation between hospital size and CDI testing rate. Hospitals using SATT or assays not detecting toxin reported significantly higher CDI rates than those using recommended methods, despite testing similar testing frequencies. These data are consistent with higher false-positive rates in such (non-recommended) testing scenarios. Cases in Italy and those diagnosed by SATT or methods NOT detecting toxin were significantly older. Testing occurred significantly earlier in the UK. Assessment of testing practice is paramount to the accurate interpretation and comparison of CDI rates

Possible Seasonality of Clostridium difficile in Retail Meat, Canada

We previously reported Clostridium difficile in 20% of retail meat in Canada, which raised concerns about potential foodborne transmissibility. Here, we studied the genetic diversity of C. difficile in retail meats, using a broad Canadian sampling infrastructure and 3 culture methods. We found 6.1% prevalence and indications of possible seasonality (highest prevalence in winter)

Clostridium difficile Infection in Patients Discharged from US Short-stay Hospitals, 1996–20031

Clinicians should be aware of the increasing risk of C. difficile–associated disease and make efforts to control its transmission

Predictors of first recurrence of clostridium difficile infection: Implications for initial management

Symptomatic recurrence of Clostridium difficile infection (CDI) occurs in approximately 20 of patients and is challenging to treat. Identifying those at high risk could allow targeted initial management and improve outcomes. Adult toxin enzyme immunoassay-positive CDI cases in a population of approximately 600 000 persons from September 2006 through December 2010 were combined with epidemiological/clinical data. The cumulative incidence of recurrence ≥14 days after the diagnosis and/or onset of first-ever CDI was estimated, treating death without recurrence as a competing risk, and predictors were identified from cause-specific proportional hazards regression models. A total of 1678 adults alive 14 days after their first CDI were included; median age was 77 years, and 1191 (78) were inpatients. Of these, 363 (22) experienced a recurrence ≥14 days after their first CDI, and 594 (35) died without recurrence through March 2011. Recurrence risk was independently and significantly higher among patients admitted as emergencies, with previous gastrointestinal ward admission(s), last discharged 4-12 weeks before first diagnosis, and with CDI diagnosed at admission. Recurrence risk also increased with increasing age, previous total hours admitted, and C-reactive protein level at first CDI (all P <. 05). The 4-month recurrence risk increased by approximately 5 (absolute) for every 1-point increase in a risk score based on these factors. Risk factors, including increasing age, initial disease severity, and hospital exposure, predict CDI recurrence and identify patients likely to benefit from enhanced initial CDI treatment

Clostridium difficile infection among hospitalized HIV-infected individuals: epidemiology and risk factors: results from a case-control study (2002-2013).

BACKGROUND: HIV infection is a risk factor for Clostridium difficile infection (CDI) yet the immune deficiency predisposing to CDI is not well understood, despite an increasing incidence of CDI among such individuals. We aimed to estimate the incidence and to evaluate the risk factors of CDI among an HIV cohort in Italy. METHODS: We conducted a retrospective case-control (1:2) study. Clinical records of HIV inpatients admitted to the National Institute for Infectious Disease "L. Spallanzani", Rome, were reviewed (2002-2013). CASES: HIV inpatients with HO-HCFA CDI, and controls: HIV inpatients without CDI, were matched by gender and age. Logistic regression was used to identify risk factors associated with CDI. RESULTS: We found 79 CDI episodes (5.1 per 1000 HIV hospital admissions, 3.4 per 10000 HIV patient-days). The mean age of cases was 46 years. At univariate analysis factors associated with CDI included: antimycobacterial drug exposure, treatment for Pneumocystis pneumonia, acid suppressant exposure, previous hospitalization, antibiotic exposure, low CD4 cell count, high Charlson score, low creatinine, low albumin and low gammaglobulin level. Using multivariate analysis, lower gammaglobulin level and low serum albumin at admission were independently associated with CDI among HIV-infected patients. CONCLUSIONS: Low gammaglobulin and low albumin levels at admission are associated with an increased risk of developing CDI. A deficiency in humoral immunity appears to play a major role in the development of CDI. The potential protective role of albumin warrants further investigation