A persistence model of the national minimum wage

This paper utilises the panel element of the BHPS (waves 9 to 14) to examine the dynamics of the National Minimum Wage (NMW) introduced to Britain in 1999. Specifically a persistence measure based on a random effects probit model for those affected by the NMW is constructed. The conditional probabilities imply some degree of state dependence, but there is also a considerable amount of turnover from one year to the next among those affected by the NM

The dynamics of the national minimum wage: transitions between different labour market states

An important policy issue is whether the National Minimum Wage (NMW) introduced in Britain in April 1999, is a stepping stone to higher wages or traps workers in a low-wage no-wage cycle. In this paper we utilise the longitudinal element of the Labour Force Survey over the period 1999 to 2003 to model transitions between different labour market states payment at or below the NMW, above the NMW, unemployment and inactivity, using a multinomial logit approach. It appears that for many workers payment at or below the NMW is of relatively short duration and a substantial number move into higher paid jobs

On the Brownian gas: a field theory with a Poissonian ground state

As a first step towards a successful field theory of Brownian particles in interaction, we study exactly the non-interacting case, its combinatorics and its non-linear time-reversal symmetry. Even though the particles do not interact, the field theory contains an interaction term: the vertex is the hallmark of the original particle nature of the gas and it enforces the constraint of a strictly positive density field, as opposed to a Gaussian free field. We compute exactly all the n-point density correlation functions, determine non-perturbatively the Poissonian nature of the ground state and emphasize the futility of any coarse-graining assumption for the derivation of the field theory. We finally verify explicitly, on the n-point functions, the fluctuation-dissipation theorem implied by the time-reversal symmetry of the action.Comment: 31 page

Picture-Hanging Puzzles

We show how to hang a picture by wrapping rope around n nails, making a polynomial number of twists, such that the picture falls whenever any k out of the n nails get removed, and the picture remains hanging when fewer than k nails get removed. This construction makes for some fun mathematical magic performances. More generally, we characterize the possible Boolean functions characterizing when the picture falls in terms of which nails get removed as all monotone Boolean functions. This construction requires an exponential number of twists in the worst case, but exponential complexity is almost always necessary for general functions.Comment: 18 pages, 8 figures, 11 puzzles. Journal version of FUN 2012 pape

Current Prescribing Practices for Skin and Soft Tissue Infections in Nursing Homes

Objectives Antibiotic stewardship has been called for across all sites of health care, including nursing homes (NHs). Skin and soft tissue infections (SSTIs) are the third most common indication for antibiotics in the NH, and so should be a focus of stewardship. This study audited medical records to identify signs and symptoms of SSTIs treated with antibiotics in relation to the McGeer criteria for surveillance, the Loeb minimum criteria for antibiotic initiation, and prescribing recommendations of the Infectious Disease Society of America. Design Cross-sectional study. Setting Thirty-one NHs in Southeastern United States. Measurements Chart data from a random sample of 161 antibiotic prescriptions for SSTIs were abstracted. To meet the McGeer criteria, pus was present at a suspected SSTI site, or at least four of the following findings were documented as present at the site: new or worsening warmth, redness, swelling, tenderness, serous drainage, or a constitutional finding. The Loeb minimum criteria for initiating antibiotics included findings of new or increasing purulent drainage at a suspected SSTI site or at least two of the following findings: fever or new or worsening redness, tenderness, warmth, or swelling at the suspected site. Audits also collected the name, route, and duration of the associated antibiotic. Analyses calculated the types of diagnoses and evaluated associations between published criteria and prescribing. Results Cellulitis, skin/soft tissue injury with infection, and abscess were diagnosed in 37% (N = 59), 18% (N = 29), and 16% (N = 26) of cases, respectively; 27% (N = 43) had less specific diagnoses. The McGeer criteria were met in 25% (N = 40), and the Loeb minimum criteria were met in 48% (N = 77) of cases. Doxycycline was the most frequently prescribed antibiotic. The mean treatment length was 9.6 days (standard deviation, 5.6), and the median length of treatment was 8.5 days (range, 3-45). Conclusion SSTIs are not routinely diagnosed or treated according to recommended standards of care, and prescriptions for systemic antibiotics appear to be frequently initiated without regard to recommended definitions of infection or therapies for the associated diagnoses. These findings indicate that SSTIs present various opportunities to improve antibiotic stewardship

Studies of the Action of Some Anti-Inflammatory Drugs on Complement Mediated Immune Haemolysis

1. The effects of various anti-inflammatory and non-anti-inflammatory drugs on complement mediated haemolysis have been studied. Drugs which were significantly protein-bound were found to inhibit this form of immune lysis, but only at greater concentrations than achieved therapeutically. 2. Removal of the drugs by prolonged dialysis resulted in restoration of complement activity with the exceptions of phenylbutazone and warfarin sodium. 3. Reconstitution experiments indicated that C2 and some of the later components especially C7 were affected by the drug. 4. Intra-articular injections of prednislone (100 mg) in patients with rheumatoid arthritis failed to produce significant changes in the synovial fluid component system. 5. None of the drugs affected by the antibody to antigen, or the ability of sensitised sheep cells to fix complement

Identification and single-cell functional characterization of an endodermally biased pluripotent substate in human embryonic stem cells

Human embryonic stem cells (hESCs) display substantial heterogeneity in gene expression, implying the existence of discrete substates within the stem cell compartment. To determine whether these substates impact fate decisions of hESCs we used a GFP reporter line to investigate the properties of fractions of putative undifferentiated cells defined by their differential expression of the endoderm transcription factor, GATA6, together with the hESC surface marker, SSEA3. By single-cell cloning, we confirmed that substates characterized by expression of GATA6 and SSEA3 include pluripotent stem cells capable of long-term self-renewal. When clonal stem cell colonies were formed from GATA6-positive and GATA6-negative cells, more of those derived from GATA6-positive cells contained spontaneously differentiated endoderm cells than similar colonies derived from the GATA6-negative cells. We characterized these discrete cellular states using single-cell transcriptomic analysis, identifying a potential role for SOX17 in the establishment of the endoderm-biased stem cell state

The Nursing Home Pneumonia Risk Index: A Simple, Valid MDS-Based Method of Identifying 6-Month Risk for Pneumonia and Mortality

Background Pneumonia is the leading infectious cause of hospitalization and death for nursing home (NH) residents; however, diagnosis is often delayed because classic signs of infection are not present. We sought to identify NH residents at high risk for pneumonia, to identify persons to target for more intensive surveillance and preventive measures. Methods Based on a literature review, we identified key risk factors for pneumonia and compiled them for use as prediction tool, limiting risk factors to those available on the Minimum Data Set (MDS). Next, we tested the tool's ability to predict 6-month pneumonia incidence and mortality rates in a sample of 674 residents from 7 NHs, evaluating it both as a continuous and a dichotomous variable, and applying both logistic regression and survival analysis to calculate estimates. Results NH Pneumonia Risk Index scores ranged from −1 to 6, with a mean of 2.1, a median of 2, and a mode of 2. For the outcome of pneumonia, a 1-point increase in the index was associated with a risk odds ratio of 1.26 (P =.038) or a hazard ratio of 1.24 (P =.037); using it as a dichotomous variable (≤2 vs ≥3), the corresponding figures were a risk odds ratio of 1.78 (P =.045) and a hazard ratio of 1.82 (P =.025). For the outcome of mortality, a 1-point increase in the NH Pneumonia Risk Index was associated with a risk odds ratio of 1.58 (P =.002) and a hazard ratio of 1.45 (P =.013); using the index as a dichotomous variable, the corresponding figures were a risk odds ratio of 3.71 (P <.001) and a hazard ratio of 3.29 (P =.001). Conclusions The NH Pneumonia Risk Index can be used by NH staff to identify residents for whom to apply especially intensive preventive measures and surveillance. Because of its strong association with mortality, the index may also be valuable in care planning and discussion of advance directives

Urine culture testing in community nursing homes: Gateway to antibiotic overprescribing

OBJECTIVE To describe current practice around urine testing and identify factors leading to overtreatment of asymptomatic bacteriuria in community nursing homes (NHs) DESIGN Observational study of a stratified random sample of NH patients who had urine cultures ordered in NHs within a 1-month study period SETTING 31 NHs in North Carolina PARTICIPANTS 254 NH residents who had a urine culture ordered within the 1-month study period METHODS We conducted an NH record audit of clinical and laboratory information during the 2 days before and 7 days after a urine culture was ordered. We compared these results with the urine antibiogram from the 31 NHs. RESULTS Empirical treatment was started in 30% of cases. When cultures were reported, previously untreated cases received antibiotics 89% of the time for colony counts of ≥100,000 CFU/mL and in 35% of cases with colony counts of 10,000-99,000 CFU/mL. Due to the high rate of prescribing when culture results returned, 74% of these patients ultimately received a full course of antibiotics. Treated and untreated patients did not significantly differ in temperature, frequency of urinary signs and symptoms, or presence of Loeb criteria for antibiotic initiation. Factors most commonly associated with urine culture ordering were acute mental status changes (32%); change in the urine color, odor, or sediment (17%); and dysuria (15%). CONCLUSIONS Urine cultures play a significant role in antibiotic overprescribing. Antibiotic stewardship efforts in NHs should include reduction in culture ordering for factors not associated with infection-related morbidity as well as more scrutiny of patient condition when results become available