Prevalence and Antimicrobial Agent Susceptibility of Methicillin-resistant Staphylococcus aureus in Healthy Pediatric Outpatients in Las Vegas

Colonization and infection by community-associated resistant strains of Staphylococcus aureus are being reported in epidemic proportions. The purpose of this study was to determine the local prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization in children and to characterize the MRSA isolates in the laboratory with regard to antimicrobial agent susceptibility patterns, and the presence of the mecA and the Panton-Valentine leukocidin (PVL) genes. Nasal swabs were collected at two pediatric clinics from a total of 505 children during health maintenance visits. A brief questionnaire was administered to collect demographic data and pertinent medical, family, and social history. Samples were cultured onto 2 selective media for S. aureus and MRSA. Potential MRSA isolates were further evaluated by real-time polymerase chain reaction (PCR), and for susceptibility to eight antibiotics by disk diffusion. Culture results showed that MRSA was present in 15 of the 505 specimens (3.0%). Six different antimicrobial susceptibility profiles were observed among the MRSA isolates. PCR amplification results showed that all 15 MRSA isolates were positive for the presence of the mecA gene, and 10 MRSA isolates contained the PVL gene. Understanding local prevalence rates and the role of colonization in infection are needed to develop effective interventions to reduce MRSA infections

Microbial Contamination on Ambulance Surfaces: A Systematic Literature Review

Healthcare-associated infections (HAIs) are infections that patients acquire while receiving medical treatment in a healthcare facility. During ambulatory transport, the patient may be exposed to pathogens transmitted from emergency medical service (EMS) personnel or EMS surfaces. The aim of this study was to determine whether organisms commonly associated with HAIs have been detected on surfaces in the patient-care compartment of ambulances. Five electronic databases – PubMed, Scopus, Web of Science, Embase and Google Scholar were used to search for articles using inclusion and exclusion criteria following the PRISMA checklist. Inclusion criteria consisted of articles published in English, between 2009 and 2020, had positive samples collected from the patient-care compartment of a ground ambulance, and reported sample collection methods of either swab sampling and/or Replicate Organism Detection and Counting (RODAC) contact plates. Studies not meeting these criteria were excluded from this review. From a total of 1376 articles identified, 16 were included in the review. Organisms associated with HAIs were commonly detected in the patient-care compartment of ambulances across a variety of different surfaces, including blood pressure cuffs, oxygen apparatuses, and areas of patient stretchers. A high prevalence of pathogenic bacteria in ambulances suggests that standard protocols related to cleaning compliance may not be effective. The primary recommendation is that designated subject matter experts in infection prevention should be incorporated as liaisons in the pre-hospital setting, acting as a link between the pre-hospital (e.g., ambulance transport) and hospital environments

Emergent spatial patterns of competing benthic and pelagic algae in a river network: A parsimonious basin-scale modeling analysis

Algae, as primary producers in riverine ecosystems, are found in two distinct habitats: benthic and pelagic algae typically prevalent in shallow/small and deep/large streams, respectively. Over an entire river continuum, spatiotemporal patterns of the two algal communities reflect specificity in habitat preference determined by geomorphic structure, hydroclimatic controls, and spatiotemporal heterogeneity in nutrient loads from point- and diffuse-sources. By representing these complex interactions between geomorphic, hydrologic, geochemical, and ecological processes, we present here a new river-network-scale dynamic model (CnANDY) for pelagic (A) and benthic (B) algae competing for energy and one limiting nutrient (phosphorus, P). We used the urbanized Weser River Basin in Germany (7th-order; ~8.4 million population; ~46 K km2) as a case study and analyzed simulations for equilibrium mass and concentrations under steady median river discharge. We also examined P, A, and B spatial patterns in four sub-basins. We found an emerging pattern characterized by scaling of P and A concentrations over stream-order ω, whereas B concentration was described by three distinct phases. Furthermore, an abrupt algal regime shift occurred in intermediate streams from B dominance in ω≤3 to exclusive A presence in ω≥6. Modeled and long-term basin-scale monitored dissolved P concentrations matched well for ω>4, and with overlapping ranges in ω<3. Power-spectral analyses for the equilibrium P, A, and B mass distributions along hydrological flow paths showed stronger clustering compared to geomorphological attributes, and longer spatial autocorrelation distance for A compared to B. We discuss the implications of our findings for advancing hydro-ecological concepts, guiding monitoring, informing management of water quality, restoring aquatic habitat, and extending CnANDY model to other river basins

Infection Prevention and the Protective Effects of Unidirectional Displacement Flow Ventilation in the Turbulent Spaces of the Operating Room

Background: Unidirectional displacement flow (UDF) ventilation systems in operating rooms are characterized by a uniformity of velocity 80% and protect patients and operating room personnel against exposure to hazardous substances. However, the air below the surgical lights and in the surrounding zone is turbulent, which impairs the ventilation system’s effect. Aim: We first used the recovery time (RT) as specified in International Organization for Standardization 14644 to determine the particle reduction capacity in the turbulent spaces of an operating room with a UDF system. Methods: The uniformity of velocity was analyzed by comfort-level probe grid measurements in the protected area below a hemispherical closed-shaped and a semi-open column-shaped surgical light (tilt angles: 0/15/30) and in the surrounding zone of a research operating room. Thereafter, RTs were calculated. Results: At a supply air volume of 10,500 m3/h, the velocity, reported as average uniformity+standard deviation, was uniform in the protected area without lights (95.8% + 1.7%), but locally turbulent below the hemispherical closedshaped (69.3% + 14.6%), the semi-open column-shaped light (66.9% + 10.9%), and in the surrounding zone (51.5%+17.6%). The RTs ranged between 1.1 and 1.7 min below the lights and 3.5+0.28 min in the surrounding zone and depended exponentially on the volume flow rate. Conclusions: Compared to an RT of 20 min as required for operating rooms with mixed dilution flow, particles here were eliminated 12–18 times more quickly from below the surgical lights and 5.7 times from the surrounding zone. Thus, the effect of the lights was negligible and the UDF’s retained its strong protective effect

Analysing the polarisation of the CMB with spin scale-discretised wavelets

We discuss a new scale-discretised directional wavelet transform to analyse spin signals defined on the sphere, in particular the polarisation of the cosmic microwave background (CMB).Comment: 1 page, Proceedings of International BASP Frontiers Workshop 201

Spectral bounds for the Hellmann potential

The method of potential envelopes is used to analyse the bound state spectrum of the Schroedinger Hamiltonian H=-\Delta+V(r), where the Hellmann potential is given by V(r) = -A/r + Be^{-Cr}/r, A and C are positive, and B can be positive or negative. We established simple formulas yielding upper and lower bounds for all the energy eigenvalues.Comment: 9 pages, 2 figures, typos correcte

Controlling magnetic anisotropy in La_0.7Sr_0.3MnO₃ nanostructures

We have developed a chlorine based dry etching process for nanopatterning the ferromagnetic oxide La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> (LSMO). Large arrays of millions of identical structures have been fabricated from thin LSMO films by electron-beam lithography and reactive ion etching. SQUID magnetometry demonstrates that patterned nanostructures with lateral dimensions down to 100 nm retain their full magnetization and the Curie temperature of the bulk layer. In addition, their shape anisotropy is sufficient to overcome the crystalline anisotropy of the bulk. High resolution scanning transmission electron microscopy shows that crystallinity is preserved even at the edges of the nanostructures

Is Entrepreneurial Success Predictable? An Ex-Ante Analysis of the Character-Based Approach

This paper empirically analyzes whether the character-based approach, which focuses on the personality structure and the human capital of business founders, allows prediction of entrepreneurial success. A unique data set is used consisting of 414 persons whose personal characteristics were analyzed by different methods, namely an one-day assessment center (AC) and a standardized questionnaire, before they launched their business. Results are partly unexpected and weaker than previous ex-post findings: first, we found correlations between the AC data and the questionnaire in one subgroup only. Second, the predictive power of the AC data is slightly better than that of the questionnaire, but lower than expected in theory. Interestingly, for those subgroups where the AC data have low predictive power, the questionnaire does better. Third, when success is measured in terms of employees hired, the character-based approach is a poor predictor. Copyright 2008 The Authors.

A Crystal Structure of the Bifunctional Antibiotic Simocyclinone D8, Bound to DNA Gyrase

Simocyclinones are bifunctional antibiotics that inhibit bacterial DNA gyrase by preventing DNA binding to the enzyme. We report the crystal structure of the complex formed between the N-terminal domain of the Escherichia coli gyrase A subunit and simocyclinone D8, revealing two binding pockets that separately accommodate the aminocoumarin and polyketide moieties of the antibiotic. These are close to, but distinct from, the quinolone-binding site, consistent with our observations that several mutations in this region confer resistance to both agents. Biochemical studies show that the individual moieties of simocyclinone D8 are comparatively weak inhibitors of gyrase relative to the parent compound, but their combination generates a more potent inhibitor. Our results should facilitate the design of drug molecules that target these unexploited binding pockets

Proporción diaria de alimento del diablillo antártico (pleuragramma antarcticum boulenger, 1902) en el este del mar de weddell

[EN] The daily ration of Pleuragramma antarcticum in the Eastern Weddell Sea was investigated from midwater and bottom trawl samples collected in the Antarctic in the summer of 1998. Using a gastric evacuation model that takes into account Weddell Sea temperature below zero and information on the prey type daily ration estimates were: 1.133% BW for immature fish of 10-16 cm and 0.484% BW for mature fish of 17-24 cm. The low daily ration intake was influenced by the low temperatures that limited the rate of gastric evacuation. This model seems more realistic than results from the classic Elliot & Persson and Eggers models that are also used in this paper, since their assumptions on feeding regularity are more rigid and they do not consider data of energy density of the prey[ES] La ración diaria de alimento de Pleuragramma antarcticum en el mar de Weddell es investigada en muestras de arrastres de fondo y pelágicas recogidas durante diferentes horas del día en el verano antártico de 1998. Utilizando un modelo de evacuación gástrica que tiene en cuenta la temperatura bajo del Mar de Weddell e información sobre el tipo de presa, las estimaciones de consumo diario fueron: 1.133% BW para peces inmaduros entre 10 -16 cm y 0.484% BW para peces maduros entre 17-24 cm. La baja ración diaria ingerida estuvo influida por las bajas temperaturas que limitan la tasa de evacuación gástrica. Este modelo parece más realista que los resultados de los modelos clásicos de Elliot & Persson and Eggers también empleados, ya que sus asunciones sobre su periodicidad de alimentación son más rígidas y no consideran datos de densidad energética de las presasThis work was conducted under the SCAR EASIZ programme, and was supported by the Alfred Wegener Institute and the Spanish Antarctic ProgrammePeer reviewe