Since the early 1990s, the Netherlands has experienced several large measles epidemics, in 1992-94, 1999-2000 and in 2013-14. These outbreaks mainly affected orthodox Protestants, a geographically ...clustered population with overall lower measles-mumps-rubella first dose (MMR-1) vaccination coverage (60%) than the rest of the country (> 95%). In the 2013-14 epidemic described here, which occurred between 27 May 2013 and 12 March 2014, 2,700 cases were reported. Several control measures were implemented including MMR vaccination for 6-14-month-olds and recommendations to reduce the risk in healthcare workers. The vast majority of reported cases were unvaccinated (94%, n = 2,539), mostly for religious reasons (84%, n = 2,135). The median age in the epidemic was 10 years, 4 years older than in the previous epidemic in 1999-2000. A likely explanation is that the inter-epidemic interval before the 2013-2014 epidemic was longer than the interval before the 1999-2000 epidemic. The size of the unvaccinated orthodox Protestant community is insufficient to allow endemic transmission of measles in the Netherlands. However, large epidemics are expected in the future, which is likely to interfere with measles elimination in the Netherlands and elsewhere.
To differentiate between the effects of heat stress (HS) and decreased dry matter intake (DMI) on physiological and metabolic variables in growing beef cattle, we conducted an experiment in which a ...thermoneutral (TN) control group (n
=
6) was pair fed (PF) to match nutrient intake with heat-stressed Holstein bull calves (n
=
6). Bulls (4 to 5 mo old, 135
kg body weight BW) housed in climate-controlled chambers were subjected to 2 experimental periods (P): (1) TN (18
°C to 20
°C) and ad libitum intake for 9 d, and (2) HS (cyclical daily temperatures ranging from 29.4
°C to 40.0
°C) and ad libitum intake or PF (in TN conditions) for 9 d. During each period, blood was collected daily and all calves were subjected to an intravenous insulin tolerance test (ITT) on day 7 and a glucose tolerance test (GTT) on day 8. Heat stress reduced (12%) DMI and by design, PF calves had similar nutrient intake reductions. During P1, BW gain was similar between environments and averaged 1.25
kg/d, and both HS and PF reduced (
P
<
0.01) average daily gain (-0.09
kg/d) during P2. Compared to PF, HS decreased (
P
<
0.05) basal circulating glucose concentrations (7%) and tended (
P
<
0.07) to increase (30%) plasma insulin concentrations, but neither HS nor PF altered plasma nonesterified fatty acid concentrations. Although there were no treatment differences in P2, both HS and PF increased (
P
<
0.05) plasma urea nitrogen concentrations (75%) compared with P1. In contrast to P1, both HS and PF had increased (16%) glucose disposal, but compared with PF, HS calves had a greater (67%;
P
<
0.05) insulin response to the GTT. Neither period nor environment acutely affected insulin action, but during P2, calves in both environments tended (
P
=
0.11) to have a blunted overall glucose response to the ITT. Independent of reduced nutrient intake, HS alters post-absorptive carbohydrate (basal and stimulated) metabolism, characterized primarily by increased basal insulin concentrations and insulin response to a GTT. However, HS-induced reduction in feed intake appears to fully explain decreased average daily gain in Holstein bull calves.
A dated sediment core from an eutrophic mangrove area presented non-significant differences in carbon accumulation rates before (55.7±10.2gm−2yr−1) and after three decades of deforestation ...(59.7±7.2gm−2yr−1). Although eutrophication effects appear to compensate the loss of mangrove organic matter input, the results in this work show a threefold lower carbon accumulation than the global averages estimated for mangrove sediments. The effects of increasing eutrophication and enhanced sediment dry bulk density observed after deforestation (~30% higher) did not result in higher carbon stocks. Moreover, the lower TOC:OP (<400) and C:N (~20) molar ratios, as well as increased nutrient accumulation, reflect the dominance of phytoplankton-derived organic matter after deforestation, resulting in less-efficient sedimentary carbon sinks. These results indicate that the organic material deposited from eutrophication may not compensate mangrove deforestation losses on carbon accumulation in mangrove ecosystems.
•Sedimentary carbon flux was not significantly lower after deforestation.•Changes in TOC:OP and C:N ratios reflected eutrophication-driven algal deposition.•Mangrove deforestation resulted in the deposition of more labile organic matter.•Resulting carbon flux was three-fold lower than the mangrove global average.
The kinematics of inertial particles suspended in the near-wall region of Newtonian and non-Newtonian turbulent channel flows was experimentally investigated. The non-Newtonian fluid was a ...homogeneous solution of 90 part per million of a polyacrylamide polymer in water with 66% drag reduction. All the experiments were performed at the same volumetric flow rate with Reynolds number of 34,300 based on bulk velocity, channel height, and the kinematic viscosity of water. The inertial particles were 250-μm glass beads with
St
of 35 (in water) at a volumetric concentration of 0.05%. A time-resolved two-dimensional particle tracking velocimetry was used to record particle images at acquisition frequency of 17.6 kHz and detect trajectory of flow tracers and the glass beads. The recorded data were processed using a two-dimensional particle tracking algorithm to obtain the Lagrangian kinematics of the beads. The comparison between laden flows of water and polymer solution showed reduction of number density of the beads and their momentum in the vicinity of the wall in the polymeric flow. The polymer solution remarkably reduced the wall-normal and shear Reynolds stresses of the beads, but had a negligible effect on their streamwise Reynolds stress. The wall-normal fluctuation of the beads reduced in the polymeric flow and their trajectories became parallel with the channel wall. Results also showed that the ejection and sweep motions were not the major mechanism for wall-normal distribution of the beads in the polymeric flow. Outcomes suggest that drag-reducing polymer solutions have the potential of reducing erosive wear in particle-laden pipelines.
Graphic abstract
This paper develops the architecture of a digital PWM controller for application in multiphase voltage regulation modules (VRMs). In this context, passive current sharing and VRM transient response ...with nonzero controller delay are analyzed. A scheme for sensing a combination of the VRM output voltage and output current with a single low-resolution window analog-to-digital converter (ADC) is proposed. The architecture and IC implementation of a digital PWM (DPWM) generation module, using a ring-oscillator-multiplexer scheme, is discussed. Experimental results from a prototype VRM and a partial controller IC implementation are presented.
The emergence of
as a significant human diarrheal pathogen is associated with the production of highly transmissible spores and the acquisition of antimicrobial resistance genes (ARGs) and virulence ...factors. Unlike the hospital-associated
RT027 lineage, the community-associated
RT078 lineage is isolated from both humans and farm animals; however, the geographical population structure and transmission networks remain unknown. Here, we applied whole-genome phylogenetic analysis of 248
RT078 strains from 22 countries. Our results demonstrate limited geographical clustering for
RT078 and extensive coclustering of human and animal strains, thereby revealing a highly linked intercontinental transmission network between humans and animals. Comparative whole-genome analysis reveals indistinguishable accessory genomes between human and animal strains and a variety of antimicrobial resistance genes in the pangenome of
RT078. Thus, bidirectional spread of
RT078 between farm animals and humans may represent an unappreciated route disseminating antimicrobial resistance genes between humans and animals. These results highlight the importance of the "One Health" concept to monitor infectious disease emergence and the dissemination of antimicrobial resistance genes.
Site-specific contamination related to fertilizer industry activity was demonstrated by light rare earth element (REE) anomalies (sum of La, Ce, Pr, Nd, Sm, and Eu concentrations up to 4.141 mg kg
−1
...) and radionuclides (
210
Pb and
226
Ra activities up to 994 and 498 Bq kg
−1
, respectively) from industrial contamination, within a subtropical estuary (SE Brazil). Anthropogenic influence was also supported by the site-specific
210
Pb and
226
Ra distribution down the estuarine system. The distribution of REE and radionuclide contamination varied along the estuary, which reflected differing sedimentation patterns of phosphogypsum and/or phosphate ore pollutants as identified downstream from the source, likely influenced by sediment–hydrodynamic processes within the estuarine system. Redox- and ion exchange-sensitive pollutants are mobile at the fresh–sea water interface causing an uneven distribution of the pollutants, indicating that the phosphgypsum and/or phosphate ore pollutant deposition can be also influenced by physical and/or geochemical processes associated to estuarine systems.
This paper develops a multimode control strategy which allows for efficient operation of the buck converter over a wide load range. A method for control of synchronous rectifiers as a direct function ...of the load current is introduced . The function relating the synchronous-rectifier timing to the load current is optimized on-line with a gradient power-loss-minimizing algorithm. Only low-bandwidth measurements of the load current and a power-loss-related quantity are required, making the technique suitable for digital controller implementations. Compared to alternative loss-minimizing approaches, this method has superior adjustment speed and robustness to disturbances, and can simultaneously optimize multiple parameters. The proposed synchronous-rectifier control also accomplishes an automatic, optimal transition to discontinuous-conduction mode at light load. Further, by imposing a minimum duty-ratio, the converter automatically enters pulse-skipping mode at very light load. Thus, the same controller structure can be used in both fixed-frequency pulsewidth modulation and variable-frequency pulse-skipping modes. These techniques are demonstrated on a digitally-controlled 100-W buck converter
Abstract
We present a family of self-consistent axisymmetric rotating globular cluster models which are fitted to spectroscopic data for NGC 362, NGC 1851, NGC 2808, NGC 4372, NGC 5927 and NGC 6752 ...to provide constraints on their physical and kinematic properties, including their rotation signals. They are constructed by flattening Modified Plummer profiles, which have the same asymptotic behaviour as classical Plummer models, but can provide better fits to young clusters due to a slower turnover in the density profile. The models are in dynamical equilibrium as they depend solely on the action variables. We employ a fully Bayesian scheme to investigate the uncertainty in our model parameters (including mass-to-light ratios and inclination angles) and evaluate the Bayesian evidence ratio for rotating to non-rotating models. We find convincing levels of rotation only in NGC 2808. In the other clusters, there is just a hint of rotation (in particular, NGC 4372 and NGC 5927), as the data quality does not allow us to draw strong conclusions. Where rotation is present, we find that it is confined to the central regions, within radii of R ≤ 2r
h
. As part of this work, we have developed a novel q-Gaussian basis expansion of the line-of-sight velocity distributions, from which general models can be constructed via interpolation on the basis coefficients.
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