686 research outputs found
Terms of Trade Shocks and Economic Performance Under Different Exchange Rate Regimes
The impact of terms of trade shocks on a country’s output and price level are, according to economic theory, expected to vary according to the de facto exchange rate regime. This paper tests this hypothesis how terms of trade shocks impact on 22 African countries, which operate different de facto exchange rate regimes, using a structural VAR with long-run restrictions, over the period from 1980 to 2007. The empirical findings support the view that the exchange rate regime matters as to how countries respond to exogenous external shocks like terms of trade shocks, in that output variation is greater for countries with fixed regimes, while for flexible regime countries real exchange rate variation reduces the need for output variability.Terms of Trade, Exchange Rate Regimes, Structural VARs
Dynamics of precipitation pattern formation at geothermal hot springs
We formulate and model the dynamics of spatial patterns arising during the
precipitation of calcium carbonate from a supersaturated shallow water flow.
The model describes the formation of travertine deposits at geothermal hot
springs and rimstone dams of calcite in caves. We find explicit solutions for
travertine domes at low flow rates, identify the linear instabilities which
generate dam and pond formation on sloped substrates, and present simulations
of statistical landscape evolution
Fundamental nursing care: a systematic review of the evidence on the effect of nursing care interventions for nutrition, elimination, mobility and hygiene
This is the final version of the article. Available from Wiley via the DOI in this record.AIMS AND OBJECTIVES: To determine the effects of nursing interventions for people's nutrition, elimination, mobility and hygiene needs. BACKGROUND: Patient experience of health care is sensitive to nursing quality. A refocus on fundamental nursing care is undermined by lack of evidence of effectiveness for interventions in core areas such as elimination, nutrition, mobility and hygiene. DESIGN: SYSTEMATIC REVIEW: METHODS: We searched for and included experimental studies on interventions by professionally qualified and unregistered nurses that addressed participants' nutrition, elimination, mobility and hygiene needs. We extracted data on scope, quality and results of studies followed by descriptive narrative synthesis of included study outcomes using a novel form of harvest plots. RESULTS: We included 149 studies, 35 nutrition, 56 elimination, 16 mobility, 39 hygiene, and three addressing two or more areas simultaneously (67 randomised controlled trials (RCTs), 32 non-RCTs and 50 uncontrolled trials). Studies into interventions on participant self-management of nutrition (n=25), oral health (n=26), catheter care (n=23), and self-management of elimination (n=21) were the most prevalent. Most studies focussed their outcomes on observational or physiological measures, with very few collecting patient reported outcomes, such as quality of life, experience or self-reported symptoms. All but 13 studies were of low quality and at significant risk of bias. The majority of studies did not define primary outcomes, included multiple measures of identical concepts, used inappropriate analyses, and did not conform to standard reporting quality criteria. CONCLUSIONS: The current evidence for fundamental nursing care interventions is sparse, of poor quality and unfit to provide evidence-based guidance to practising nurses. This article is protected by copyright. All rights reserved.This study was funded by a Programme Development Grant from the UK National Institute of Health Research (NIHR). RP-DG-1214-10001. David Richards and Victoria Goodwin receive funding support from the UK National Institute for Health Research South West Peninsula Collaboration for Leadership in Applied Health Research and Care
Listeria monocytogenes Invades the Epithelial Junctions at Sites of Cell Extrusion
Listeria monocytogenes causes invasive disease by crossing the intestinal epithelial barrier. This process depends on the interaction between the bacterial surface protein Internalin A and the host protein E-cadherin, located below the epithelial tight junctions at the lateral cell-to-cell contacts. We used polarized MDCK cells as a model epithelium to determine how L. monocytogenes breaches the tight junctions to gain access to this basolateral receptor protein. We determined that L. monocytogenes does not actively disrupt the tight junctions, but finds E-cadherin at a morphologically distinct subset of intercellular junctions. We identified these sites as naturally occurring regions where single senescent cells are expelled and detached from the epithelium by extrusion. The surrounding cells reorganize to form a multicellular junction that maintains epithelial continuity. We found that E-cadherin is transiently exposed to the lumenal surface at multicellular junctions during and after cell extrusion, and that L. monocytogenes takes advantage of junctional remodeling to adhere to and subsequently invade the epithelium. In intact epithelial monolayers, an anti-E-cadherin antibody specifically decorates multicellular junctions and blocks L. monocytogenes adhesion. Furthermore, an L. monocytogenes mutant in the Internalin A gene is completely deficient in attachment to the epithelial apical surface and is unable to invade. We hypothesized that L. monocytogenes utilizes analogous extrusion sites for epithelial invasion in vivo. By infecting rabbit ileal loops, we found that the junctions at the cell extrusion zone of villus tips are the specific target for L. monocytogenes adhesion and invasion. Thus, L. monocytogenes exploits the dynamic nature of epithelial renewal and junctional remodeling to breach the intestinal barrier
The Clostridium difficile problem: A South African tertiary institution's prospective perspective
BACKGROUND AND OBJECTIVES: The aim of this study is to report the incidence of Clostridium difficile-associated disease (CDAD) in a tertiary-care hospital in South Africa and to identify risk factors, assess patient outcomes and determine the impact of the hypervirulent strain of the organism referred to as North American pulsed-field type 1 (NAP1). METHODS: Adults who presented with diarrhoea over a period of 15 months were prospectively evaluated for CDAD using stool toxin enzyme immunoassay (EIA). Positive specimens were evaluated by PCR. Patient demographics, laboratory parameters and outcomes were analysed. RESULTS: CDAD was diagnosed in 59 (9.2%) of 643 patients (median age 39 years, IQR 30 - 55). Thirty-four (58%) were female. Recent antibiotic exposure was reported in 39 (66%), 27 (46%) had been hospitalised within 3 months, and 14 (24%) had concomitant inflammatory bowel disease (IBD). Nineteen (32%) had community-acquired CDAD (CA-CDAD). The annual incidence of hospital-acquired CDAD (HA-CDAD) was 8.7 cases/10 000 hospitalisations. Two cases of the hypervirulent strain NAP1 were identified. Seven (12%) patients underwent colectomy (OR 6.83; 95% CI 2.41 - 19.3). On logistic regression, only antibiotic exposure independently predicted for CDAD (OR 2.9; 95% CI 1.6 - 5.1). Three (16%) cases of CA-CDAD reported antibiotic exposure (v. 90% of HA-CDAD, p<0.0001). Twelve (86%) patients had concomitant IBD (p<0.0001 v. HA-CDAD). CA-CDAD was significantly associated with antibiotic exposure (OR 0.04, 95% CI 0.01 - 0.24) and IBD (OR 9.6, 95% CI 1.15 - 79.8). CONCLUSION: The incidence of HA-CDAD in the South African setting is far lower than that reported in the West. While antibiotic use was a major risk factor for HA-CDAD, CA-CDAD was not associated with antibiotic therapy. Concurrent IBD was a predictor of CA-CDAD
Dyadic influences on awareness of condition in people with dementia: findings from the IDEAL cohort
Copyright \ua9 2023 Alexander, Martyr, Gamble, Quinn, Pentecost, Morris, Clare and on behalf of the IDEAL study team.Introduction: The discrepancy between caregiver-ratings and self-ratings of abilities is commonly used to assess awareness in people with dementia. We investigated the contribution of caregiver and dyadic characteristics to the difference in perspective between caregiver-informants and people with dementia about difficulties experienced, when considering awareness of condition. Methods: We conducted exploratory cross-sectional analyses using data from the IDEAL cohort. Participants were 1,038 community-dwelling people with mild-to-moderate dementia, and coresident spouse/partner caregivers. The Representations and Adjustment to Dementia Index (RADIX) checklist reporting difficulties commonly experienced in dementia was completed by 960 caregiver-informants and 989 people with dementia. Difference in scores was calculated for 916 dyads. Demographic information, cognition, informant-rated functional ability and neuropsychiatric symptoms were recorded for the person with dementia. Self-reported data were collected on mood, comorbidity, religion, importance of religion, relationship quality, and caregiver stress. Results: For most dyads, caregivers reported more RADIX difficulties than people with dementia. Caregiver RADIX ratings were more closely associated with informant-rated functional ability and neuropsychiatric symptoms than with cognition. More RADIX difficulties and higher stress were reported by female caregivers. Greater RADIX difference was associated with more caregiver stress, and older age but less depression in people with dementia. Conclusion: Few dyadic characteristics were important, but caregiver stress was higher where caregivers reported more RADIX difficulties and/or the difference in perspective was greater, whereas partners with dementia reported better mood. In addition to offering information about awareness of condition, the caregiver rating and difference in perspectives could indicate where more support is needed
Identifying aggregate supply and demand shocks in small open economies:empirical evidence from African countries
This paper uses a tri-variate structural VAR with a long-run identification scheme, akin to the Blanchard and Quah method, to identify external and domestic supply and demand shocks in 22 African countries between 1980 and 2005. Domestic supply shocks are found to be the most important factor contributing over 70% to output fluctuations in these countries, with external shocks playing a relatively minor role. A partial correlation analysis between the identified shocks and a measure of the fiscal policies of the countries revealed that the fiscal policies pursued by most of the countries during the period are counter-cyclical
Exchange rate regime verification:An alternative method of testing for regime changes
This work proposes a change in persistence test for identifying de facto exchange rate regime changes. The results from 25 African countries show that this approach is able to identify some regime changes not captured by existing methods
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