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To determine infection prevention and control (IPAC) practices for carbapenemase-producing Enterobacteriaceae (CPE), an emerging threat, at acute-care hospitals in Ontario, Canada.
A descriptive cross-sectional survey.
We surveyed IPAC directors and managers at all acute-care hospitals in Ontario, Canada, to gather information on IPAC practices related to CPE, including admission screening, other patient screening, environmental testing, use of precautions to prevent transmission, and outbreak management.
Of 116 acute-care hospitals, 105 (91%) responded. Admission screening included patients previously colonized or infected with CPE (n = 64, 61%), patients recently hospitalized outside of Canada (Indian subcontinent, n = 62, 59%; other countries, n = 56, 53%), and patients recently hospitalized in Canada (n = 22, 21%). Fifty-one hospitals (49%) screened patients for colonization during an outbreak. Almost all hospitals (n = 101, 96%) used precautions to prevent transmission from patients with CPE colonization or infection; most hospitals (n = 54, 53%) continued precautions indefinitely. Few hospitals (n = 19, 18%) performed environmental cultures. Eight hospitals (8%) reported at least 1 outbreak, and 6 hospitals (6%) reported transmission from sink or shower drains to patients.
Variability in practices may result from lack of evidence and challenges in updating guidelines as evidence emerges. A coordinated approach to slow the emergence of CPE should be considered in our population.
The aim of the study was to determine the main factors (sociodemographic, anthropometric, lifestyle and health status) associated with high Na excretion in a representative population of Chile.
Na excretion (g/d), a valid marker of Na intake, was determined by urine analysis and Tanaka’s formulas. Blood pressure was measured by trained staff and derived from the mean of three readings recorded after 15 min rest. The associations of Na excretion with blood pressure and the primary correlates of high Na excretion were determined using logistic regression.
Chileans aged ≥15 years.
Participants (n 2913) from the Chilean National Health Survey 2009–2010.
Individuals aged 25 years or over, those who were obese and those who had hypertension, diabetes or metabolic syndrome were more likely to have higher Na excretion. The odds for hypertension increased by 10·2 % per 0·4 g/d increment in Na excretion (OR=1·10; 95 % CI 1·06, 1·14; P < 0·0001). These findings were independent of major confounding factors.
Age, sex, adiposity, sitting behaviours and existing co-morbidities such as diabetes were associated with higher Na excretion levels in the Chilean population. These findings could help policy makers to implement public health strategies tailored towards individuals who are more likely to consume high levels of dietary salt.
Maritime accident statistics reveal that ship collisions are among the most frequent and severe accidents. The same statistics indicate that most of them are caused by human error, mainly due to breaches of the International Regulations for Preventing Collisions at Sea (COLREGs) and to the lack of communication between ships. There are also special situations where there is some ambiguity in the application of the COLREGs. In such occasions, and if there is no communication between the ships involved, compliance with the Rules may still end up in a collision. This article brings a new approach to Collision Avoidance Systems (CAS) and presents the earliest stages in the development of safety functions for the reduction of ship-to-ship collision risk on the high seas. These functions will help the concerned ships achieve coordinated compliance with the COLREGs. Functional safety standards are applied and, in their implementation, real, accessible electronic programmable systems (hardware and software) will be used.
This article is devoted to studying which conditions imply that a topological dynamical system is mean sensitive and which do not. Among other things, we show that every uniquely ergodic, mixing system with positive entropy is mean sensitive. On the other hand, we provide an example of a transitive system which is cofinitely sensitive or Devaney chaotic with positive entropy but fails to be mean sensitive. As applications of our theory and examples, we negatively answer an open question regarding equicontinuity/sensitivity dichotomies raised by Tu, we introduce and present results of locally mean equicontinuous systems and we show that mean sensitivity of the induced hyperspace does not imply that of the phase space.
The synthesis and antiprotozoal activity of some simple dialkyl pyrazole-3,5-dicarboxylates (compounds 2–6) and their sodium salts (pyrazolates) (compounds 7–9) against Trypanosoma cruzi, Leishmania infantum and Leishmania braziliensis are reported. In most cases the studied compounds showed, especially against the clinically significant amastigote forms, in vitro activities higher than those of the reference drugs (benznidazole for T. cruzi and glucantime for Leishmania spp.); furthermore, the low non-specific cytotoxicities against Vero cells and macrophages shown by these compounds led to good selectivity indexes, which are 8–72 times higher for T. cruzi amastigotes and 15–113 times higher for Leishmania spp. amastigotes than those of the respective reference drugs. The high efficiency of diethyl ester 3 and its sodium salt 8 against the mentioned protozoa was confirmed by further in vitro assays on infection rates and by an additional in vivo study in a murine model of acute and chronic Chagas disease. The inhibitory capacity of compounds 3 and 8 on the essential iron superoxide dismutase of the aforementioned parasites may be related to the observed anti-trypanosomatid activity. The low acute toxicity of compounds 3 and 8 in mice is also reported in this article.
Effect systems have the potential to help software developers, but their practical adoption has been very limited. We conjecture that this limited adoption is due in part to the difficulty of transitioning from a system where effects are implicit and unrestricted to a system with a static effect discipline, which must settle for conservative checking in order to be decidable. To address this hindrance, we develop a theory of gradual effect checking, which makes it possible to incrementally annotate and statically check effects, while still rejecting statically inconsistent programs. We extend the generic type-and-effect framework of Marino and Millstein with a notion of unknown effects, which turns out to be significantly more subtle than unknown types in traditional gradual typing. We appeal to abstract interpretation to develop and validate the concepts of gradual effect checking. We also demonstrate how an effect system formulated in the framework of Marino and Millstein can be automatically extended to support gradual checking. We use gradual effect checking to develop a fully gradual type-and-effect framework, which permits interaction between static and dynamic checking for both effects and types.
We define weaker forms of topological and measure-theoretical equicontinuity for topological dynamical systems, and we study their relationships with sequence entropy and systems with discrete spectrum. We show that for topological systems equipped with ergodic measures having discrete spectrum is equivalent to
-mean equicontinuity. In the purely topological category we show that minimal subshifts with zero topological sequence entropy are strictly contained in diam-mean equicontinuous systems; and that transitive almost automorphic subshifts are diam-mean equicontinuous if and only if they are regular (i.e. the maximal equicontinuous factor map is one–one on a set of full Haar measure). For both categories we find characterizations using stronger versions of the classical notion of sensitivity. As a consequence, we obtain a dichotomy between discrete spectrum and a strong form of measure-theoretical sensitivity.
This paper focuses on the impact of process parameters of gas metal arc welding (GMAW) on the mechanisms of fail and wear present in the contact tips (CT), component located in the welding gun, when high strength low alloy (HSLA) steel is welded with ER70S - 0.045” copper coated electrode in manual mode. By means of chemical analysis the alloy was identified as C12200. It was also identified that the maximum temperature reached by the CT is 850° C. 30 samples were obtained that had different lifetime, which were analyzed by stereoscope and its behavior against wear was determined by using an equation of relative wear. Microstructural changes as recrystallization and grain growth undergone by these CT were also evidenced by light microscopy. In addition the changes in their mechanical properties such as decrease in their hardness to about of half that initially had. Finally some significant samples were analyzed by scanning electron microscopy (SEM); microanalysis was used to identify the exchange of matter leaving from the electrode in the CT and spatter into the hole of the component.
Macrophages are widely distributed immune system cells with essential functions in tissue homeostasis, apoptotic cell clearance, and first defense in infections. A distinguishing feature of activated macrophages participating in different situations such as inflammatory and metabolic diseases is the presence of increased numbers of lipid-rich organelles, termed lipid bodies (LBs) or lipid droplets, in their cytoplasm. LBs are considered structural markers of activated macrophages and are involved in different functions such as lipid metabolism, intracellular trafficking, and synthesis of inflammatory mediators. In this review, we revisit the distinct morphology of LB organelles actively formed within macrophages in response to infections and cell clearance, taking into account new insights provided by ultrastructural studies. We also discuss the LB interactions within macrophages, revealed by transmission electron microscopy, with a focus on the remarkable LB–phagosome association and discuss potential links between structural aspects and function.
Eu3+, Bi3+ codoped Lu2O3 powders (Eu = 2.5 at.%, Bi = 0–3.0 at.%) were prepared using the sol–gel method. Fourier transform infrared spectroscopy, x-ray diffraction, and excitation and emission spectra were carried out to characterize the synthesis, structure, and luminescent properties. The excitation spectra show a strong peak at 350–390 nm, corresponding to the Bi3+1S0 → 3P1 transition, and the emission spectra present the emission from 5D0 → 7FJ (J = 0, 1, 2, 3, 4) level of Eu3+. The intensity of the reddish emission at 612 nm was monitored as a function of the Bi3+ content and showed a light yield increment of ≈400% compared to a monodoped sample at 1.0% at. Bi3+, produced by an energy transfer process from Bi3+ to Eu3+. This was a consequence of the overlapping of the Bi3+3P1 → 1S0 emission with the f–f Eu3+ transitions.
Wastewaters often contain offensive cations. Because of their high affinity for water, it is difficult to remove those using conventional solvents for liquid- liquid extraction . Hydrophobic ionic liquids may provide a useful extraction process. Because the properties of ionic liquids are turnable, it may be possible to identify some ionic liquids that have low viscosity, very low solubility in water, and high affinity for select metal ions . In this sense in this work liquid- liquid extraction of dilute Zn ions from water was performed near room temperature with two ionic liquids (IL). Distribution coefficients are reported for Zn ions extracted with bromide 1-hexyl-pyridinium and bromide 1-octyl-pyridinium diluted in decanol. The extraction has been studied, and these confirmed that the metal extraction proceeds via a cation – exchange mechanism. Furthermore, stripping of Zn (II) from ILs into an aqueous phase by sulfuric acid (1 M) and recycling of the extracting ILs phase was successfully accomplished.
Transplantation of spermatogonial stem cells (SSCs), the male germline stem cells, in experimental animal models has been successfully used to study mechanisms involved in SSC self-renewal and to restore fertility. However, there are still many challenges associated with understanding the recipient immune response for SSCs use in clinical therapies. Here, we have undertaken a detailed structural study of macrophages elicited by SSCs transplantation in mice using both high-resolution light microscopy (HRLM) and transmission electron microscopy (TEM). We demonstrate that SSCs transplantation elicits a rapid and potent recruitment of macrophages into the seminiferous epithelium (SE). Infiltrating macrophages were derived from differentiation of peritubular monocyte-like cells into typical activated macrophages, which actively migrate through the SE, accumulate in the tubule lumen, and direct phagocytosis of differentiating germ cells and spermatozoa. Quantitative TEM analyses revealed increased formation of lipid bodies (LBs), organelles recognized as intracellular platforms for synthesis of inflammatory mediators and key markers of macrophage activation, within both infiltrating macrophages and Sertoli cells. LBs significantly increased in number and size in parallel to the augmented macrophage migration during different times post-transplantation. Our findings suggest that LBs may be involved with immunomodulatory mechanisms regulating the seminiferous tubule niche after SSC transplantation.
Adequate nutritional support is essential for normal infant growth and development. Infants with congenital cardiac disease are known to be at risk for growth failure. We sought to describe perioperative growth in infants undergoing surgical repair of two-ventricle congenital cardiac disease and assess for predictors of their pattern of growth.
Materials and methods
Full-term infants who underwent surgical repair of two-ventricle congenital cardiac disease at a single institution were enrolled in a retrospective cohort study performed following a larger prospective study. Infants with facial, gastrointestinal, or neurologic anomalies, trisomy chromosomal abnormality, birth weight less than 2500 grams, or those transferred to another institution before discharge home were excluded. The primary outcome was change in weight-for-age z score from surgery to discharge. Our secondary outcome variable was post-operative hospital length of stay.
A total of 76 infants met the inclusion criteria. Medain age at surgery was 5 days with a range from 1 to 44. The median weight-for-age z score at surgery was −0.2 with a range from −2.9 to 2.8 and by discharge had dropped to −1.2 with a range from −3.4 to 1.8. The median change in weight-for-age z score from surgery to discharge was −1.0 with a range from −2.3 to 0.2. Delayed post-operative nutrition (p < 0.001) and reintubation following initial post-operative extubation (p = 0.001) were associated with decrease in weight-for-age z score.
Infants undergoing repair of two-ventricle congenital cardiac disease had poor growth in the post-operative period. This may be mitigated by early initiation of post-operative nutrition.
Brazing process is a cost effective technique to repair wide gap cracks in turbine components made from difficult to weld nickel base superalloys. In this process boron and silicon are used as melting point depressants, however, form hard and brittle intermetallic compounds with nickel (eutectic phases) which are detrimental to the mechanical properties of brazed joints. In this paper the effect of brazing parameters such as temperature and time on final microstructure of brazed joint of nickel base superalloy Inconel 738 using a commercial filler metal alloy (Ni-11Cr-3.5Si-2.25B-3.5Fe) was investigated. The microstructure of the joint layer was characterized by optical and scanning electron microscopy; chemical composition was carried out by energy dispersive X-ray spectrometry (EDS) microanalysis and microhardness testing. The results showed that the formation of eutectic microconstituents, within the joint regions, was significantly influenced by the brazing parameters and gap size, also that formation of eutectic constituents decreased by allowing a sufficient amount of time for a complete isothermal solidification to take place at the brazing temperature.
We studied the potential applications of Portland cement and Portland cement-Metakaolin blends as scaffolding materials for load bearing bone tissue engineering. Cementitious pastes were prepared by mixing Portland cement and Metakaolin at different ratios (100:0, 85:15), and hydrated under a concentrated CO2 atmosphere (carbonated pastes). Pastes fabricated similarly, but hydrated under normal atmospheric conditions were used for comparison (non-carbonated pastes). Compressive tests were run to evaluate the mechanical properties of the pastes. The bioactivity of the samples was tested in a simulated body fluid (SBF) solution for 1 and 4 days. Sample morphology and chemistry were characterized via scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The cytocompatibility was studied using human osteosarcoma (HOS) cell cultures and the direct contact assay. Mechanical characterization did not show significant differences in the compressive strength of the blends compared to pure cement controls. The bioactivity test revealed that the pastes induced surface precipitation of calcium phosphate (CaP) when exposed to the SBF solution (as confirmed by SEM and EDS). Non-carbonated pastes induced early CaP precipitation. Cytocompatibility experiments showed that the carbonated blends allowed adequate cell growth. Non-carbonated blends presented a highly cytotoxic behavior. The introduction of Metakaolin did not affect the cytocompatibility of the samples. These results show that Portland cement and Portland cement-Metakaolin blends could present suitable characteristics for applications as scaffolding materials in load bearing bone tissue engineering.
The purpose of this study was to assess the pattern of weight change from surgical intervention to home discharge and to determine predictors of poor growth in this population of infants with congenital cardiac disease.
Neonates with functionally univentricular physiology enrolled in a prospective cohort study examining growth between March, 2003 and May, 2007 were included. Weights were collected at birth, before surgical intervention, and at hospital discharge. In addition, retrospective echocardiographic data and data about post-operative complications were reviewed. Primary outcome variables were weight-for-age z-score at discharge and change in weight-for-age z-score between surgery and discharge.
A total of 61 infants met the inclusion criteria. The mean change in weight-for-age z-score between surgery and hospital discharge was minus 1.5 plus or minus 0.8. Bivariate analysis revealed a significant difference in weight-for-age z-score between infants who were discharged on oral feeds, minus 1.1 plus or minus 0.8 compared to infants with feeding device support minus 1.7 plus or minus 0.7, p-value equal to 0.01. Lower weight-for-age z-score at birth, presence of moderate or greater atrioventricular valve regurgitation, post-operative ventilation time, and placement of an additional central venous line were associated with 60% of the variance in weight-for-age z-score change.
Neonates undergoing staged surgical repair for univentricular physiology are at significant risk for growth failure between surgery and hospital discharge. Haemodynamically significant atrioventricular valve regurgitation and a complex post-operative course were risk factors for poor post-operative weight gain. Feeding device support appears to be insufficient to ensure adequate weight gain during post-operative hospitalisation.
This study confirms the diet and determines the trophic position of the bentfin devil ray (Mobula thurstoni) and spinetail devil ray (Mobula japanica) in the south-west Gulf of California. There has been an active fishery in the area for these filter-feeding elasmobranchs, which are highly susceptible to exploitation due to low fecundity and long lifespan. However, information on their basic biology is scarce. δ13C and δ15N values of devil rays and zooplankton (sorted according to trophic level: herbivores, carnivores and omnivores) were determined over a period of 11 months, to allow for isotopic temporal variations in isotopic signals at the base of the food web. On the basis of fractionation factors we determined that bentfin and spinetail devil rays fed mainly on Nyctiphanes simplex, the most abundant euphausiid in neritic waters of the Gulf of California. The trophic positions obtained for the devil rays correspond to second level consumers.
We studied the relationships between soil nutrient availability and microbial biomass and activity of two contrasting soil conditions in a tropical deciduous forest in western Mexico. Hilltops have higher pH, water, dissolved organic C, and ammonium concentrations than hillslopes. Our main hypothesis was that soil microbial biomass, microbial activity and bacterium species richness would be higher in soils with high availability of nutrients. Fifteen soil cores, 0–5 cm depth, were taken in the dry, early rainy and rainy season, from each of the ten replicate plots in hilltop and hillslope positions located on three contiguous small watersheds. We measured moisture, C, N and P availability, potential C mineralization, net nitrification, microbial biomass and culturable heterotrophic and nitrifying bacteria in composite samples from each plot. Microbial biomass, species richness of culturable heterotrophic bacteria and C mineralization were significantly higher on hilltops than on hillslopes. Net nitrification was, in contrast, significantly higher on hillslopes than on hilltops and counts of culturable nitrifying bacteria were also significantly higher in the rainy-season samples. Hilltops and hillslopes had low similarity in composition of culturable heterotrophic bacterial species, particularly during the rainy season. The results suggested that C and N availability and seasonal changes in soil moisture are important controlling factors for some soil culturable-bacterial species, which may affect both C mineralization and nitrification in these tropical deciduous forest soils.
Se abordan cuatro temas en la replica a Iriarte et. al (en este volumen): 1) Reconstrucciones paleoclimáticas, analizando la baja resolución del registro de Iriarte (2006), limitaciones del procedimiento de muestreo, sistema acuático elegido y dataciones. Se responde a las criticas sobre las inferencias paleoclimdticas realizadas, indicando que no consideran el total de las líneas de evidencia utilizadas ni la escala del registro y señalando la buena correspondencia con reconstrucciones propuestas para la región. 2) Evidencias de aldeas estructuradas en sitios con estructuras monticulares. Observamos las argumenlaciones esgrimidas para el sitio de Los Ajos, refiriendolas al contexto arqueológico de la región. Se responde a nuestra supuesta falta de observation de cambios culturales y ambientales, señalándose los problemas de las secuencias culturales propuestas. Se retoma el problema de la mecánica de construcción de los montículos como cuestión inicial a la horn de interpretar el registro y postular secuencias culturales. 3) Dataciones, desarrollando el concepto de fechados de baja resolutión y su pertinencia en la propuesta del Modelo de Crecimiento Continuo para las estructuras monticulares. 4) Por último se observa las implicaciones de la confusión entre la cuenca del Plata y la cuenca de la Laguna Merín.