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The learning hospital is distinguished by ceaseless evolution of erudition, enhancement, and implementation of clinical best practices. We describe a model for the learning hospital within the framework of a hospital infection prevention program and argue that a critical assessment of safety practices is possible without significant grant funding. We reviewed 121 peer-reviewed manuscripts published by the VCU Hospital Infection Prevention Program over 16 years. Publications included quasi-experimental studies, observational studies, surveys, interrupted time series analyses, and editorials. We summarized the articles based on their infection prevention focus, and we provide a brief summary of the findings. We also summarized the involvement of nonfaculty learners in these manuscripts as well as the contributions of grant funding. Despite the absence of significant grant funding, infection prevention programs can critically assess safety strategies under the learning hospital framework by leveraging a diverse collaboration of motivated nonfaculty learners. This model is a valuable adjunct to traditional grant-funded efforts in infection prevention science and is part of a successful horizontal infection control program.
Some studies found that providing micronutrient powder (MNP) causes adverse health outcomes, but modifying factors are unknown. We aimed to investigate whether Fe status and inherited Hb disorders (IHbD) modify the impact of MNP on growth and diarrhoea among young Lao children. In a double-blind controlled trial, 1704 children of age 6–23 months were randomised to daily MNP (with 6 mg Fe plus fourteen micronutrients) or placebo for about 36 weeks. IHbD, and baseline and final Hb, Fe status and anthropometrics were assessed. Caregivers provided weekly morbidity reports. At enrolment, 55·6 % were anaemic; only 39·3 % had no sign of clinically significant IHbD. MNP had no overall impact on growth and longitudinal diarrhoea prevalence. Baseline Hb modified the effect of MNP on length-for-age (LAZ) (P for interaction = 0·082). Among children who were initially non-anaemic, the final mean LAZ in the MNP group was slightly lower (–1·93 (95 % CI –1·88, –1·97)) v. placebo (–1·88 (95 % CI –1·83, –1·92)), and the opposite occurred among initially anaemic children (final mean LAZ –1·90 (95 % CI –1·86, –1·94) in MNP v. –1·92 (95 % CI –1·88, –1·96) in placebo). IHbD modified the effect on diarrhoea prevalence (P = 0·095). Among children with IHbD, the MNP group had higher diarrhoea prevalence (1·37 (95 % CI 1·17, 1·59) v. 1·21 (95 % CI 1·04, 1·41)), while it was lower among children without IHbD who received MNP (1·15 (95 % CI 0·95, 1·39) v. 1·37 (95 % CI 1·13, 1·64)). In conclusion, there was a small adverse effect of MNP on growth among non-anaemic children and on diarrhoea prevalence among children with IHbD.
We assessed the impact of an embedded electronic medical record decision-support matrix (Cerner software system) for the reduction of hospital-onset Clostridioides difficile. A critical review of 3,124 patients highlighted excessive testing frequency in an academic medical center and demonstrated the impact of decision support following a testing fidelity algorithm.
The spatial-intensity profile of light reflected during the interaction of an intense laser pulse with a microstructured target is investigated experimentally and the potential to apply this as a diagnostic of the interaction physics is explored numerically. Diffraction and speckle patterns are measured in the specularly reflected light in the cases of targets with regular groove and needle-like structures, respectively, highlighting the potential to use this as a diagnostic of the evolving plasma surface. It is shown, via ray-tracing and numerical modelling, that for a laser focal spot diameter smaller than the periodicity of the target structure, the reflected light patterns can potentially be used to diagnose the degree of plasma expansion, and by extension the local plasma temperature, at the focus of the intense laser light. The reflected patterns could also be used to diagnose the size of the laser focal spot during a high-intensity interaction when using a regular structure with known spacing.
Palaeochannels of lowland rivers provide a means of investigating the sensitivity of river response to climate-driven hydrologic change. About 80 palaeochannels of the lower Macquarie River of southeastern Australia record the evolution of this distributive fluvial system. Six Macquarie palaeochannels were dated by single-grain optically stimulated luminescence. The largest of the palaeochannels (Quombothoo, median age 54 ka) was on average 284 m wide, 12 times wider than the modern river (24 m) and with 21 times greater meander wavelength. Palaeo-discharge then declined, resulting in a younger, narrower, group of palaeochannels, Bibbijibbery (125 m wide, 34 ka), Billybingbone (92 m, 20 ka), Milmiland (112 m, 22 ka), and Mundadoo (86 m, 5.6 ka). Yet these channels were still much larger than the modern river and were continuous downstream to the confluence with the Barwon-Darling River. At 5.5 ka, a further decrease in river discharge led to the formation of the narrow modern river, the ecologically important Macquarie Marshes, and Marra Creek palaeochannel (31 m, 2.1 ka) and diminished sediment delivery to the Barwon-Darling River as palaeo-discharge fell further. The hydrologic changes suggest precipitation was a driving forcing on catchment discharge in addition to a temperature-driven runoff response.
Two single-nucleotide polymorphisms (SNPs) (rs4281084 and rs12155594) within the neuregulin-1 (NRG1) gene have been associated with psychosis transition. However, the neurobiological changes associated with these SNPs remain unclear. We aimed to determine what relationship these two SNPs have on lateral ventricular volume and white matter integrity, as abnormalities in these brain structures are some of the most consistent in schizophrenia.
Structural (n = 370) and diffusion (n = 465) magnetic resonance imaging data were obtained from affected and unaffected individuals predominantly of European descent. The SNPs rs4281084, rs12155594, and their combined allelic load were examined for their effects on lateral ventricular volume, fractional anisotropy (FA) as well as axial (AD) and radial (RD) diffusivity. Additional exploratory analyses assessed NRG1 effects on gray matter volume, cortical thickness, and surface area throughout the brain.
Individuals with a schizophrenia age of onset ⩽25 and a combined allelic load ⩾3 NRG1 risk alleles had significantly larger right (up to 50%, padj = 0.01) and left (up to 45%, padj = 0.05) lateral ventricle volumes compared with those with allelic loads of less than three. Furthermore, carriers of three or more risk alleles, regardless of age of onset and case status, had significantly reduced FA and elevated RD but stable AD in the frontal cortex compared with those carrying fewer than three risk alleles.
Our findings build on a growing body of research supporting the functional importance of genetic variation within the NRG1 gene and complement previous findings implicating the rs4281084 and rs12155594 SNPs as markers for psychosis transition.
The ex situ lift out (EXLO) adhesion forces are reviewed and new applications of EXLO for focused ion beam (FIB)-prepared specimens are described. EXLO is used to manipulate electron transparent specimens on microelectromechanical systems carrier devices designed for in situ electron microscope analysis. A new patented grid design without a support film is described for EXLO. This new slotted grid design provides a surface for holding the specimen in place and also allows for post lift out processing. Specimens may be easily manipulated into a backside orientation to reduce FIB curtaining artifacts with this slotted grid. Large EXLO specimens can be manipulated from Xe+ plasma FIB prepared specimens. Finally, applications of EXLO and manipulation of FIB specimens using a vacuum probe lift out method are shown. The vacuum probe provides more control for placing specimens on the new slotted grids and also allows for easy manipulation into a backside configuration.
Pharmacogenetic/pharmacogenomic (PGx) testing is currently available for a wide range of health problems including cardiovascular disease, cancer, diabetes, autoimmune disorders, mental health disorders and infectious diseases. PGx contributes important information to the field of precision medicine by clarifying appropriate treatments for specific disease subtypes. Tangible benefits to patients including improved outcomes and reduced total health care costs have been observed. However, PGx-guided therapy faces many barriers to full integration into clinical practice and acceptance by stakeholders, whether practitioner, patient or payer. Each stakeholder has a unique perspective on the role of PGx testing, although all are similarly challenged with demonstrating or appraising its cost-to-benefit value. Coverage by insurers is a critical step in achieving widespread adoption of PGx testing. The acceleration of adoption of precision medicine in general and for PGx testing in particular will be determined by how quickly robust evidence can be accumulated that shows a return on investment for payers in terms of real dollars, for clinicians in terms of patient clinical responses, and for patients in terms of economic, health and quality of life outcomes. Trends in PGx testing utilization and uptake by payers in real-world practice are discussed; the role of pharmacoeconomics in assessing cost-effectiveness is highlighted using a case study in psychiatric care, and several issues that will affect adoption of PGx testing in the United States (US) over the next few years are reviewed.
Determining the appropriate disposition of emergency department (ED) syncope patients is challenging. Previously developed decision tools have poor diagnostic test characteristics and methodological flaws in their derivation that preclude their use. We sought to develop a scale to risk-stratify adult ED syncope patients at risk for serious adverse events (SAEs) within 30 days.
We conducted a medical record review to include syncope patients age ≥ 16 years and excluded patients with ongoing altered mental status, alcohol or illicit drug use, seizure, head injury leading to loss of consciousness, or severe trauma requiring admission. We collected 105 predictor variables (demographics, event characteristics, comorbidities, medications, vital signs, clinical examination findings, emergency medical services and ED electrocardiogram/ monitor characteristics, investigations, and disposition variables) and information on the occurrence of predefined SAEs. Univariate and multiple logistic regression analyses were performed.
Among 505 enrolled patient visits, 49 (9.7%) suffered an SAE. Predictors of SAE and their resulting point scores were as follows: age ≥ 75 years (1), shortness of breath (2), lowest ED systolic blood pressure < 80 mm Hg (2), Ottawa Electrocardiographic Criteria present (2), and blood urea nitrogen > 15 mmol/L (3). The final score calculated by addition of the individual scores for each variable (range 0–10) was found to accurately stratify patients into low risk (score < 1, 0% SAE risk), moderate risk (score 1, 3.7% SAE risk), or high risk (score > 1, ≥ 10% SAE risk).
We derived a risk scale that accurately predicts SAEs within 30 days in ED syncope patients. If validated, this will be a potentially useful clinical decision tool for emergency physicians, may allow judicious use of health care resources, and may improve patient care and safety.
We report a systematic study of polarization and magnetic field effects on the optical response of Fe3O4-silicone elastomer composite. The Fe3O4 particles were aligned in a silicone elastomer matrix with an external static magnetic field. Films of composites containing 5wt% of 20nm ≤ d ≤ 30nm Fe3O4 particles aligned in- and out-of-plane in the elastomer host were prepared. The optical spectra of the films were measured with the Perkin-Elmer Lambda 950 UV/vis/NIR spectrometer. We observed a systematic redshift in the optical response of the outof-plane composite films with increasing static magnetic field strength, which saturated near 600 Gauss. We obtained a maximum redshift of ∼46 nm at 600 Gauss. The observed redshift in the optical response of the out-of-plane composite film is attributed to the effect of the magnetic field. This facilitated the formation of the highly aligned particles that induced strong electric dipole in the aligned particles. Interestingly, there were no observable shifts with increasing magnetic field strength in the in-plane films, suggesting that the orientation (polarization) of the magnetic dipole and the induced electric dipole play a crucial role in the optical response.
The purpose of this chapter is to show how double dividends could be obtained from using market instruments to tax water use in a developing country. The double dividends are namely environmental (water conservation) on the one hand, and poverty reduction dividends on the other. We apply a water tax on selected industries in South Africa to reduce demand for water, and then transfer the revenue from this tax to the poor to achieve reduction in absolute levels of poverty.
South Africa is classified as a semi-arid country. Precipitation has been fluctuating over the years with an average of 500 mm per annum, well below the world average of about 860 mm (DWAF 2002). The total flow of all the rivers in the country combined amounts to approximately 49 200 million m³ per year, while the National Water Resource Strategy estimated the total water requirement for the year 2000 at 13 280 million m3 per year, excluding environmental requirements. In addition, South Africa is poorly endowed in groundwater as most of the country is underlain by hard rock formations that do not contain any major groundwater aquifers (DWAF 2002).
While currently only about 24% of rural people have access to water on site, additional sources of water supply are environmentally, financially and politically hard to develop. At the same time, unemployment in rural areas of South Africa is extremely high, which results in severe poverty conditions in these areas.
The kinetics and phase formation sequence of thin-film solid-state reactions, including silicide forming reactions, have frequently been considered to be controlled by interfacial kinetic reaction barriers. These are purely phenomenological quantities which describe the finite rate of the interfacial reaction in terms of limited particle fluxes crossing the respective interfaces. No atomic mechanisms that might be responsible for the action of such barriers have so far been indicated, with the exception of Schmalzried's formulation. The latter says that the interfacial barrier is due to the limited relaxation time needed by the particles to rearrange into the proper sublattice after having crossed the interface. We present correlated kinetic and structural observations during the 2Ni + Si → NiSi2 reaction on the Si(111) surface and discuss them with the help of a model involving the formation and lateral propagation of interfacial steps of different height. The model allows us to explain the kinetic observations by reaction barriers formed as a result of the crystallographic boundary conditions of the reaction.
Previous studies have indicated that the sub-optimal performance of the San Francisco Syncope Rule (SFSR) is likely due to the misclassification of the “abnormal electrocardiogram (ECG)” variable. We sought to identify specific emergency department (ED) ECG and cardiac monitor abnormalities that better predict cardiac outcomes within 30 days in adult ED syncope patients.
This health records review included patients 16 years or older with syncope and excluded patients with ongoing altered mental status, alcohol or illicit drug use, seizure, head injury leading to loss of consciousness, or severe trauma requiring admission. We collected patient characteristics, 22 ECG variables, cardiac monitoring abnormalities, SFSR “abnormal ECG” criteria, and outcome (death, myocardial infarction, arrhythmias, or cardiac procedures) data. Recursive partitioning was used to develop the “Ottawa Electrocardiographic Criteria.”
Among 505 included patient visits, 27 (5.3%) had serious cardiac outcomes. We found that patients were at risk for cardiac outcomes within 30 days if any of the following were present: second-degree Mobitz type 2 or third-degree atrioventricular (AV) block, bundle branch block with first-degree AV block, right bundle branch with left anterior or posterior fascicular block, new ischemic changes, nonsinus rhythm, left axis deviation, or ED cardiac monitor abnormalities. The sensitivity and specificity of the Ottawa Electrocardiographic Criteria were 96% (95% CI 80–100) and 76% (95% CI 75–76), respectively.
We successfully identified specific ED ECG and cardiac monitor abnormalities, which we termed the Ottawa Electrocardiographic Criteria, that predict serious cardiac outcomes in adult ED syncope patients. Further studies are required to identify which adult ED syncope patients require cardiac monitoring in the ED and the optimal duration of monitoring and to confirm the accuracy of these criteria.
Nonautonomous parabolic equations of the form ut − Δu = f(u, t) on a symmetric domain are considered. Using the moving-hyperplane method, it is proved that any bounded nonnegative solution symmetrises as t → ∞. This is then used to show that for nonlinearities periodic in t, any non-negative bounded solution approaches a periodic solution.
Under- and over-nutrition during gestation may influence fetal hypothalamic development resulting in individuals predisposed to adverse health effects. This study examined fetuses from obese and control ewes to determine whether dam obesity alters hypothalamic expression of fetal appetite regulatory genes. A second objective was to contrast the expression of appetite regulatory genes in ewes that become the most obese to those that remained in moderate body condition on the same energy-rich diet. Multiparous, western white-faced ewes were weighed and individually fed 100% (control) or 150% (obese) of National Research Council requirements from day 60 before mating until day 75 of gestation. At day 75 of gestation, fetuses were collected and weighed. Hypothalamic tissue from fetal lambs and dams was collected and frozen for mRNA extraction. Dam obesity (P ⩾ 0.16), fetal sex (P ⩾ 0.44) or their interaction (P ⩾ 0.42) did not affect the relative expression of fetal hypothalamic regulators of appetite, including neuropeptide Y, agouti-related protein, pro-opiomelanocortin, cocaine- and amphetamine-regulated transcript and receptors for leptin. Maternal obesity at day 75 of gestation in ewes did not affect developmental mechanisms responsible for the expression of fetal appetite regulatory genes and would not be expected to predispose offspring to adult-onset obesity through disrupted appetite regulation at this developmental time point. In the ewe, appetite regulatory genes did not differ (P > 0.20) with ewe adiposity; however, expression of estrogen receptor α, but not β (P = 0.37), in the medial basal hypothalamus was greater (P = 0.04) in obese than in control ewes.