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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.
Pioneering studies of winds from non-coronal evolved late-type stars were plagued by uncertainties in the Ca ionization balance which severely limited the accuracy of derived mass-loss rates. Here we re-examine the Ca II ionization balance in these stellar winds using FUSE spectra which reveal, for the first time, the flux from the photoionizing radiation field shortward of 1045Â. We present a FUSE 912-1185Â spectroscopic survey of evolved late-K and M stars; including the M giants α Cet (M1.5 III), γ Cru (M3.5 III), β Gru (M4.5 III), and R Dor (M8e III). Using FUSE spectra of α Tau (K5 III), supplemented with partial redistribution calculations of H Ly-α and Ly-β, together with UV and radio data, we present a study of α Tau's wind ionization balance and derive new constraints which place the mass-loss rate significantly below that suggested by the Reimers formula.
The effect of the initial nitridation of the sapphire substrate on the GaN crystal quality as a function of substrate temperature was studied. GaN layers were grown by plasma-assisted molecular beam epitaxy (MBE) on sapphire substrates nitridated at different substrate temperatures. A strong improvement in the GaN crystal quality was observed at 100 °C nitridation temperature. Symmetric (0004) and asymmetric (10-5) full widths at half maximum (FWHM) of the x-ray rocking curves were 136 and 261 arcsec, respectively. This compares to an x-ray rocking curve full width at half maximum of 818 arcsec (0004) for conventional MBE buffer conditions. For our conventional buffer conditions, sapphire substrates were exposed to a N plasma at temperatures above 500 °C for 10min and then 25~50nm buffers were deposited without annealing at high temperature. The low temperature nitridation also shows an enhancement of the lateral growth of the GaN, resulting in larger grain sizes. The largest grain size achieved was approximately 2.8μm, while the average grain size was approximately 2.4μm at 100 °C nitridation temperature.
In 1867, British surgeon Joseph Lister published his landmark series On the Antiseptic Principle of the Practice of Surgery in which he presented his novel technique of applying carbolic acid on surgical wounds to destroy “septic germs” . This “aseptic” technique markedly decreased the incidence of gangrene and death and helped solidify the belief that “minute organisms” were the cause of suppuration. Rapid progress in aseptic technique followed and, coupled with the discovery of antibiotics such as penicillin in the mid-1900s, revolutionized the field of surgery from a practice that had been plagued by frequent infection and death into the discipline it is today. Yet, despite more than a century of great improvements in the prevention of surgical site infections (SSIs) and antimicrobial prophylaxis, surgery-related infections remain a problem.
Over 30 million operative procedures are performed in US hospitals each year, with an overall postsurgical infection rate of 2–5% [2,3]. Among healthcare-associated infections, surgical site infections (SSIs) are the second most common, accounting for 17–20% of all nosocomial infections [2,4]. The US Centers for Disease Control and Prevention (CDC) reports that about 500,000 SSIs occur yearly, but this number is likely an underestimation of the true burden. This underestimation probably can be attributed to the rapid proliferation of outpatient/ambulatory surgeries and shorter postoperative inpatient days, which, in turn, have made the detection of SSIs more difficult. In fact, outpatient operations accounted for 63% of all surgeries performed in US community hospitals in 2002, compared with just 16% in 1980 . In 2006, an estimated 53.3 million surgical and non-surgical procedures were performed in ambulatory surgery centers, yet there is no standardized method for SSI surveillance in these venues [2,6]. Globally, the lack of surveillance systems for SSIs in developing countries makes it difficult to gauge the worldwide burden of SSIs. However, in their meta-analysis of 220 studies of healthcare-associated infections in developing countries, Allegranzi and colleagues estimate that SSIs are the leading cause of nosocomial infections with an incidence up to three times higher than that recorded in developed countries .
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
Central line-associated bloodstream infection (CLABSI) is a national target for mandatory reporting and a Centers for Medicare and Medicaid Services target for value-based purchasing. Differences in chart review versus claims-based metrics used by national agencies and groups raise concerns about the validity of these measures.
Evaluate consistency and reasons for discordance among chart review and claims-based CLABSI events.
We conducted 2 multicenter retrospective cohort studies within 6 academic institutions. A total of 150 consecutive patients were identified with CLABSI on the basis of National Healthcare Safety Network (NHSN) criteria (NHSN cohort), and an additional 150 consecutive patients were identified with CLABSI on the basis of claims codes (claims cohort). Ail events had full-text medical record reviews and were identified as concordant or discordant with the other metric.
In the NHSN cohort, there were 152 CLABSIs among 150 patients, and 73.0% of these cases were discordant with claims data. Common reasons for the lack of associated claims codes included coding omission and lack of physician documentation of bacteremia cause. In the claims cohort, there were 150 CLABSIs among 150 patients, and 65.3% of these cases were discordant with NHSN criteria. Common reasons for the lack of NHSN reporting were identification of non-CLABSI with bacteremia meeting Centers for Disease Control and Prevention (CDC) criteria for an alternative infection source.
Substantial discordance between NHSN and claims-based CLABSI indicators persists. Compared with standardized CDC chart review criteria, claims data often had both coding omissions and misclassification of non-CLABSI infections as CLABSI. Additionally, claims did not identify any additional CLABSIs for CDC reporting. NHSN criteria are a more consistent interhospital standard for CLABSI reporting.
This study analyses whether there is a relationship between a psychiatry placement during the UK Foundation Programme and appointment to psychiatry training. A survey was distributed to all foundation year 2 doctors in the UK to determine how many have exposure to psychiatry before specialty applications and whether such exposure correlates with choosing psychiatry as a career.
The study showed that 14.6% of foundation doctors had exposure to psychiatry prior to specialty applications. Of these, 14.9% chose psychiatry as a career in contrast to only 1.8% of those who did not have psychiatry exposure (χ2P = 0.0008; risk ratio 8.19).
This study adds weight to calls to increase the proportion of psychiatry posts in the Foundation Programme as part of a broader strategy to improve recruitment. To answer this question categorically, we suggest a prospective cohort study looking at how attitudes and career preferences change with exposure to psychiatry posts.
Knowledge about the diet of fish-eating predators is critical when evaluating conflicts with the fishing industry. Numerous primary studies have examined the diet of grey seals Halichoerus grypus and common seals Phoca vitulina in a bid to understand the ecology of these predators. However, studies of large-scale spatial and temporal variation in seal diet are limited. Therefore this review combines the results of seal diet studies published between 1980 and 2000 to examine how seal diet varies at a range of spatial and temporal scales. Our results revealed extensive spatial variation in gadiform, perciform and flatfish consumption, likely reflecting variation in prey availability. Flatfish and gadiform consumption varied between years, reflecting changes in fish assemblages as a consequence of factors such as varying fishing pressures, climate change and natural fluctuations in populations. Perciform and gadiform consumption varied seasonally: in addition there was a significant interaction between season and seal species, indicating that grey and common seals exhibited different patterns of seasonal variation in their consumption of Perciformes and Gadiformes. Multivariate analysis of grey seal diet revealed spatial variation at a much smaller scale, with different species dominating the diet in different areas. The existence of spatial and temporal variation in seal diet emphasizes that future assessments of the impact of seal populations should not be based on past or localized estimates of diet and highlights the need for up-to-date, site specific estimates of diet composition in the context of understanding and resolving seal/fisheries conflict.
We have measured the transient events of the α-β martensitic transformation in nanocrystalline Ti films via single shot electron diffraction patterns with 1.5 ns temporal resolution. This was accomplished with a newly constructed dynamic transmission electron microscope (DTEM), which combines pulsed laser systems and pump-probe techniques with a conventional TEM. The DTEM thereby enables studies of transformations that are (1) far too fast to be captured by conventional bulk techniques, and (2) difficult to study with current ultrafast electron diffraction (UED) instruments (which typically require an accumulation of multiple shots for each diffraction pattern). Martensitic transformations in nanocrystalline materials meet both criteria, with their rapid nucleation, characteristic interface velocities ∼1 km/s, and significant irreversible microstructural changes. Free-standing 40-nm-thick Ti films were laser-heated at a rate of ∼1010 K/s to a temperature above the 1155 K transition point, then probed at various time intervals with a 1.5-ns-long intense electron pulse. Diffraction patterns show an almost complete transition to the β phase within 500 ns. Post-mortem analysis (after the sample is allowed to cool) shows a reversion to the α phase coupled with substantial grain growth, lath formation, and texture modification. The cooled material also shows a complete lack of apparent dislocations, suggesting the possible importance of a "massive" short-range diffusion mechanism.
The constitutive flow behavior of semi-solid metal alloy slurries has been modeled using an internal variable framework. The formulation represents the primary flow response of these materials: history dependence (thizotvopy), steady state shear rate thinning (pseudoplasticity) and constant internal structure shear rate thickening (dilatancy). The flow response at any given structure has been decoupled from structure-dependent response in carefully controlled rapid transient experiments done on a computer-controlled, high temperature, Couette geometry rheomneter. The data for Sn-15wt%Pb correlates well with the model.
Biaxial modulus and residual stress of silicon-rich silicon nitride (Si3 + xN4−x) films on silicon substrates were measured at multiple discrete locations across wafer surfaces using a versatile bulge testing method. An array of 0.2 μm thick silicon nitride membranes were fabricated across the surface of 100 mm diameter wafers. The membranes were 1 mm square. Material properties of the film were extracted by measuring the deflection of the silicon nitride membranes under controlled pressure loading conditions. Pressures from 0 to 12 psi were applied across the membranes, while their deflected shapes were measured with a white light interferometer. Numerical analysis of the measured pressure-deflection behavior of the membranes enabled the biaxial modulus and residual stress of the film to be mapped over the wafer surface. These initial results indicated that the technique was able to determine biaxial modulus to within ±1 % and residual stress within ±4 %. Furthermore, the technique can be applied to composite membranes, enabling the determination of biaxial modulus and residual stress of an additional film subsequently deposited upon the membrane film.
A test system has been assembled to examine factors controlling the reliability of microdevice switching. The system consists of a spherically tipped sputter-coated post driven by a piezoresistive actuator into a sputter-coated micromechanical membrane. Contact forces are calculated based upon the measured deflection of the micromechanical membrane, which is induced by post actuation. Membrane deflection is measured using white light interferometry. The known geometry of the membrane and probe tip permits the estimation of contact area and, hence, contact pressure. Preliminary testing of sputtered gold contacts resulted in localized melting, material transport to the membrane and failure of contact surfaces at relatively low contact pressures and current densities. Further testing will examine the factors governing the reliability of microdevice contacts, such as material properties, contact pressure and current density.
A regioregular copolymer of 3–hexylthiophene and 3–(6–hydroxyhexan–1yl)thiophene has been functionalised with biotin hydrazide; binding of avidin to the biotin moieties causes drastic changes to the absorption spectrum of the polymer in solution, and to the electrochemistry and conductivity of the polymer in thin films.