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Non-cholera Vibrio (NCV) species are important causes of disease. These pathogens are thermophilic and climate change could increase the risk of NCV infection. The El Niño Southern Oscillation (ENSO) is a ‘natural experiment’ that may presage ocean warming effects on disease incidence. In order to evaluate possible climatic contributions to observed increases in NCV infection, we obtained NCV case counts for the United States from publicly available surveillance data. Trends and impacts of large-scale oceanic phenomena, including ENSO, were evaluated using negative binomial and distributed non-linear lag models (DNLM). Associations between latitude and changing risk were evaluated with meta-regression. Trend models demonstrated expected seasonality (P < 0.001) and a 7% (6.1%–8.1%) annual increase in incidence from 1999 to 2014. DNLM demonstrated increased vibriosis risk following ENSO conditions over the subsequent 12 months (relative risk 1.940, 95% confidence interval (CI) 1.298–2.901). The ‘relative–relative risk’ (RRR) of annual disease incidence increased with latitude (RRR per 10° increase 1.066, 95% CI 1.027–1.107). We conclude that NCV risk in the United States is impacted by ocean warming, which is likely to intensify with climate change, increasing NCV risk in vulnerable populations.
Rice (Oryza sativa L.) is one of the most important cereal crops in the world and a potentially important source of zinc (Zn) in the diet. The improvement of Zn content of rice is a global challenge with implications for both rice production and human health. The objective of the present study was to identify the effects of nitrogen (N) fertilizer rates and Zn application methods on Zn content of rice by evaluating rice production on native soils with different Zn availabilities in 2010/11. The results indicated that Zn application increased rice grain yield and Zn content in grains compared with the control; however, this effect was also affected by the native soil Zn availability, N fertilizer rate and Zn fertilizer application method. The native soil Zn status was the dominant factor influencing grain yield and grain Zn content in response to Zn fertilizer application. Grain Zn content ranged from 19·74 to 26·93 mg/kg under the different Zn statuses. The results also indicated that Zn application method has a significant influence on grain yield. Application of Zn fertilizer to the soil was more effective than the foliar spray on rice grain yield; however, the foliar spray resulted in a greater increase in grain Zn content when compared with soil application. Grain Zn content was affected by application method and displayed the following general trend: soil application + foliar spray > foliar spray > soil application. The experiments investigating the effect of N fertilizer rate combined with Zn application method showed a clear increase in both grain yield and Zn content as the N fertilizer level increased from 200 to 300 kg/ha. In addition, the results also indicated that N content and accumulation increased in all plant tissues, which suggests that Zn application might influence the uptake and translocation of N in rice plants. These results suggest that soil application in addition to a foliar spray of Zn should be considered as an important strategy to increase grain yield and grain Zn content of rice grown in soils with low background levels of Zn-associated diethylene triamine pentaacetate acid. Moreover, this process could be further strengthened by a high N application rate. In conclusion, these results demonstrate the potential of optimizing nutrient management using Zn fertilizer to obtain higher grain yields and higher grain Zn content in fields with low native Zn status.
Stars are tidally disrupted and accreted when they approach massive black holes (MBHs) closely, producing a flare of electromagnetic radiation. The majority of the (approximately two dozen) tidal disruption events (TDEs) identified so far have been discovered by their luminous, transient X-ray emission. Once TDEs are detected in much larger numbers, in future dedicated transient surveys, a wealth of new applications will become possible. Here, we present the proposed Einstein Probe mission, which is a dedicated time-domain soft X-ray all-sky monitor aiming at detecting X-ray transients including TDEs in large numbers. The mission consists of a wide-field micro-pore Lobster-eye imager (60° × 60°), and is designed to carry out an all-sky transient survey at energies of 0.5-4 keV. It will also carry a more sensitive telescope for X-ray follow-ups, and will be capable of issuing public transient alerts rapidly. Einstein Probe is expected to revolutionise the field of TDE research by detecting several tens to hundreds of events per year from the early phase of flares, many with long-term, well sampled lightcurves.
Although communicable diseases have hitherto played a small part in illness associated with Olympic Games, an outbreak of infection in a national team, Games venue or visiting spectators has the potential to disrupt a global sporting event and distract from the international celebration of athletic excellence. Preparation for hosting the Olympic Games includes implementation of early warning systems for detecting emerging infection problems. Ensuring capability for rapid microbiological diagnoses to inform situational risk assessments underpins the ability to dispel rumours. These are a prelude to control measures to minimize impact of any outbreak of infectious disease at a time of intense public scrutiny. Complex multidisciplinary teamwork combined with laboratory technical innovation and efficient information flows underlie the Health Protection Agency's preparation for the London 2012 Olympic and Paralympic Games. These will deliver durable legacies for clinical and public health microbiology, outbreak investigation and control in the coming years.
Mechanical cues in cellular microenvironment are central in directing a
class of cellular behaviors such as the dynamic of cell adhesion, migration,
and differentiation. Several advanced optical techniques, such as
structured-illumination nano-profilometry (SINAP), have been developed for a
better resolution of these dynamic processes. These techniques however
require culturing cells on materials of refractive index close to that of
glass, while most studies regarding the effects of mechanical cues on
cellular dynamics were conducted on hydrogel-based substrates. Here we
report the development of culturing substrates of tunable rigidity and
refractive index suitable for SINAP studies. Polyvinyl chloride (PVC)-based
substrates were mixed with a softener called Di(isononyl)
Cyclohexane-1,2-Dicarboxylate (DINCH) and cured by heating. The volume
ratios of PVC to DINCH were varied from 1:1 to 3:1. The Young’s modulus of
the resulting substrates ranged from 18 kPa to 40 kPa. The yielded
refractive indices of the composite substrates as measured by phase contrast
tomography ranged from 1.47 to 1.53. Human lung adenocarcinoma cells CL1-5
were cultured on the composite substrates and cell viability was examined
using the MTT assay. The dynamics of cell adhesion and filopodia activities
were examined using SINAP. Preliminary results suggest that PVC based
culturing substrates have a great potential in the application of SINAP
Colossal magnetoresistive (CMR) manganites display a spectacular range of structural, magnetic, and electronic phases as a function of hole concentration, temperature, magnetic field, etc. Although the bulk of research has concentrated on the 3-D perovskite manganites, the ability to study anisotropic magnetic and electronic interactions made available in reduced dimensions has accelerated interest in the layered Ruddlesden-Popper (R-P) phases of the manganite class. The quest for understanding the coupling among lattice, spin, and electronic degrees of freedom (and dimensionality) is driven by the availability of high quality materials. In this talk, we will present recent results on synthesis and magnetic properties of layered manganites from the La2−2xSr1+2xMn2O7 series in the Mn4+-rich regime x > 0.5. This region of the composition diagram is populated by antiferromagnetic structures that evolve from the A-type layered order to G-type “rocksalt” order as x increases. Between these two regimes is a wide region (0.7 < x < 0.9) where an incommensurate magnetic structure is observed. The IC structure joins spin canting and phase separation as a mode for mixed-valent manganites to accommodate FM/AF competition. Transport in these materials is dominated by highly insulating behavior, although a region close to x = 0.5 exhibits metal-nonmetal transitions and an extreme sensitivity to oxygen content. We suggest two possible explanations for this transport behavior at doping just above x=0.5: localization by oxygen defects or charge ordering of Mn3+/Mn4+ sites.
Silica nanoparticles with metallic nanoclusters are of great interest in many applications from bio imaging to optical devices. The nanometric size of metallic particles induces specific absorption properties due to surface plasmon resonance. This absorption mainly depends on the morphology of the nanoparticles. If the encapsulation of metallic nanoparticles into a silica shell is now well developed, there is a great interest on the synthesis of either silica nanoparticles covered by metallic nanoparticles or silica cores with metallic shells. Two main ways are described in the literature to bind metallic nanoparticles onto the silica nanoparticles. The first way consists on the mixing of a metallic colloidal sol with another sol containing silica nanoparticles bringing at their surface the suitable chemical functions, able to properly interact with the metal nanoparticles. The second way consists on the use of a reducing agent to reduce the metallic ions introduced successively into a suspension of silica nanoparticles. Herein is proposed an original third method based on a double surface functionalization of the silica nanoparticles. This method is actually based on an in-situ reduction of metallic ions by two chemical function (amino and thiol) previously grafted onto the surface of the silica nanoparticles. The silica nanoparticles are synthesized by a reverse micro-emulsion sol-gel process. This synthesis gives monodispersed silica nanoparticles of 40 nm diameter. The surface functionalization of the silica nanoparticles is performed by sol-gel reactions within the micro-emulsion, using two silane-coupling agents owning either a thiol function or a diamino function.The functionalized silica shell increases the chemical activity of the surface of the nanoparticles. But the capability of this functionalized surface to reduce metallic ions depends mainly on the chemical function used. Two examples are given in this study: the diamino functions, which reduce the copper ions, and the combination of the diamino and the thiol functions in a silver nitrate solutionwhich induces the growth of small silver nanoparticles (4-5 nm) on the silica nanoparticles’ surface.
Background and objectives: Preoperative evaluation performed by anaesthesiologists primarily aims to estimate the risk of perioperative complications and to create opportunities to optimize the patients' condition before surgery. In this study an inventory was made of the current practice of preoperative evaluation in Dutch hospitals. It was estimated how many hospitals had implemented an outpatient preoperative evaluation clinic in 2004. Subsequently, current practice was compared with the results of a previous inventory (2000). It was also evaluated to what extent the guidelines of the Dutch Health Council and the Netherlands Society of Anaesthesiology were followed. Methods: The study consisted of two phases. First, a literature research was performed and pilot interviews were constructed. The interviews were conducted face-to-face with anaesthesiologists in a sample of Dutch hospitals. Based on the results, written questionnaires were constructed. In the second phase these questionnaires were sent to all general and academic hospitals in the Netherlands. Results: In 2004, 74% of the hospitals had an outpatient preoperative evaluation clinic, compared with 50% in 2000. The percentage of hospitals with an outpatient preoperative evaluation clinic available for all elective patients increased from 20% to 52%. Conclusions: The Dutch guidelines on preoperative evaluation seem to have influenced current practice. An increase in the number of outpatient preoperative evaluation clinics was seen after the guidelines were published. The implementation of an outpatient preoperative clinic seems to warrant that anaesthesiologists are carrying out the activities prescribed by the guidelines. Most hospitals without a clinic aim to implement one in the future.
Following the Nipah virus (NV) outbreak in March 1999 in Singapore, a serological survey was undertaken to screen individuals potentially exposed to NV. Blood samples were tested for NV IgM, IgG and neutralizing antibodies. Twenty-two (1·5%) of 1469 people tested had antibodies suggesting NV infection. Although 12 of the 22 infected people (54·6%) were symptomatic, the remaining 10 (45·4%) were clinically well and had no past history of compatible pulmonary or neurological disease. Clinical and serological findings suggested three people had been infected with NV before the outbreak was recognized. All those who were infected were male abattoir workers. None of the people who had contact with horses, and no healthcare workers exposed to infected patients and their specimens had detectable antibodies. This study provides evidence that NV causes asymptomatic infection. All of the antibody positive individuals had direct contact with pigs and there was no evidence of human to human transmission.
Because the three-dimensional large-scale vortex structures dominate the dispersion
of particles at intermediate Stokes numbers in shear layers, there is interest in
understanding the two-way thermal coupling effect in droplet–gas flows for practical
combustion applications. Using pseudo-spectral and Lagrangian approaches, three-dimensional
two-way thermally coupled droplet-laden mixing layers are studied with
hot air and cool water droplets. Higher air density is observed around the region of
the interface of the two streams and, thus, thermal contraction occurs in this region.
This thermal contraction results in an increase of the magnitude of the vorticity field,
a more unstable flow, a higher droplet concentration and a lower droplet dispersion
across the mixing layer.
Deposition of a (La0.5Sr0.5)CoO3 (LSCO) layer on top of Pt/Ti/Si substrates was observed to substantially improve the stability of the subsequently deposited Pb1−xLaxTi1−x/4O3 (PLT) films. Platinum coating of silicon substrates by itself is known to enhance the formation of PLT phase. In this paper, the elemental depth profile examined by secondary ion mass spectroscopy (SIMS) and the structural profile examined by grazing angle incident x-ray diffractometry (GIXD) reveals that the Ti species precoated underneath the Pt layer diffuses outward through the Pt layer at high temperature, forming a rutile TiO2 layer on top of Pt coating. It is this outermost TiO2 layer which promotes the transformation kinetics of the PLT species adhered onto substrates into the perovskite phase. Thus obtained films (PLT/Pt/Ti/Si) are, however, not stable enough to survive subsequent high-temperature processing. On the other hand, the PLT/LSCO/Pt/Ti/Si films, which incorporate LSCO as buffer layer, can survive 650 °C without significant deterioration.
The three-dimensional mixing layer is characterized by both two-dimensional
streamwise large-scale structures. Understanding the effects of those large-scale
on the dispersion of particles is very important. Using a pseudospectral
the large-scale structures of a three-dimensional temporally developing
and the associated dispersion patterns of particles were simulated. The
was used for spatial derivatives due to the periodic boundary conditions
in the streamwise and the spanwise directions and the free-slip boundary
in the transverse direction. A second-order Adam–Bashforth scheme
was used in
the time integration. Both a two-dimensional perturbation, which was based
unstable wavenumbers of the streamwise direction, and a three-dimensional
derived from an isotropic energy spectrum, were imposed initially. Particles
different Stokes numbers were traced by the Lagrangian approach based on
coupling between the continuous and the dispersed phases.
The time scale and length scale for the pairing were found to be twice
those for the
rollup. The streamwise large-scale structures develop from the initial
the most unstable wavelength in the spanwise direction was found to be
thirds of that in the streamwise direction. The pairing of the spanwise
vortices was also
found to have a suppressing effect on the development of the three-dimensionality.
Particles with Stokes number of the order of unity were found to have the
concentration on the circumference of the two-dimensional large-scale structures.
The presence of the streamwise large-scale structures causes the variation
particle concentrations along the spanwise and the transverse directions.
of variation also increases with the development of the three-dimensionality,
results in the ‘mushroom’ shape of the particle distribution.
CBA/T6 mice inoculated with Plasmodium berghei ANKA strain (PbA) exhibited cerebral symptoms and died from cerebral malaria 6–8 days p.i. whereas DBA/2J mice developed (around days 6–9) a non-fatal cerebral malaria, with milder cerebral symptoms, and died between days 15 and 22 from other malaria-related complications. When inoculated with P. berghei K173 (Pb) these mouse strains did not develop cerebral malaria. These mouse/parasite strain combinations were used, in conjunction with the retinal whole-mount technique, to elucidate factors critical in the pathology of murine cerebral malaria. CBA/T6 mice infected with PbA (PbA-CBA mice) demonstrated mild changes in vascular permeability as early as days 2–3, prior to the appearance on day 5 of cerebral symptoms, whereas mice with non-cerebral malaria did not show any vascular permeability changes until the very late stage of the disease (days 14–22). In the PbA infections, progressive deterioration of endothelial barrier properties, demonstrated by Evans' Blue leakage both generally and from specific focal areas, as well as a developing monocytosis and adherence of mononuclear cells to the endothelium of the retinal vessels continued until death (in CBA/T6 mice) or resolution (in DBA/2J mice). Adherent monocytes, particularly in PbA-CBA mice, were associated with reduced Hoechst staining of individual endothelial cells and a banking up proximally of both parasitized and non-parasitized blood cells in the small blood vessels, often with accompanying focal leakage of Evans' Blue from the retinal vessels. The occurrence and severity of these early changes in the microcirculation correlated with the subsequent development of cerebral symptoms. Monocyte margination appeared to be the most significant factor associated with the development of cerebral symptoms.
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