To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Local attitudes towards carnivores often reflect the degree of damage they are perceived to cause. Consequently, understanding the interactions between people and these species is essential to conservation efforts. This study investigated local perceptions of three Cerrado canid species and current chicken management practices, to identify the potential damage they cause and how this relates to peoples’ attitudes towards these species. Results from structured interviews at 50 ranches in Goiás, Brazil, highlighted that general knowledge about Cerrado canids differed significantly by species, with interviewees unable to correctly answer questions about the hoary fox Lycalopex vetulus and crab-eating fox Cerdocyon thous in comparison to the maned wolf Chrysocyon brachyurus. Chicken coops were identified as the most effective method for preventing predation, yet only 44% of respondents employed this method. Using a perceived predation measure, interviewees reported chicken predation by all three Cerrado canids even though most of these events were stated to occur during the day, outside the species’ active periods. Reported predation events were a strong predictor of attitude. Participants who experienced predation events reported they did not like having a Cerrado canid on their property. However, 86% of the respondents agreed that Cerrado canids should nevertheless be protected. Our findings support the need to incorporate the human dimension in canid and broader carnivore conservation issues.
Antimicrobial resistance is a limiting factor for the success of the treatment of infectious diseases and is associated with increased morbidity and cost. The present study aims to evaluate prescribing patterns of antimicrobials and quantify progress in relation to targets for quality improvement in the prescription of antimicrobials in Northern Ireland's secondary care sector using three repetitive point prevalence surveys (PPS) over a 6-year period: the European Surveillance of Antimicrobial Consumption (ESAC-PPS) in 2009 and 2011 and the Global-PPS on Antimicrobial Consumption and Resistance in 2015. Out of 3605 patients surveyed over the three time points, 1239 (34.4%) were treated with an antibiotic, the most frequently prescribed antibiotic groups were a combination of penicillins, including β-lactamase inhibitors. Compliance with hospital antibiotic policies in 2009, 2011 and 2015 were 54.5%, 71.5% and 79.9%, respectively. Likewise, an indication for treatment was recorded in patient notes 88.5%, 87.7% and 90.6% in 2009, 2011 and 2015, respectively, and surgical prophylactic antibiotic prescriptions for >24 h was 3.9%, 3.2% and 0.7% in 2009, 2011 and 2015, respectively. Treatment based on biomarker data was used in 61.5% of cases. In conclusion, a general trend in the improvement of key antimicrobial-related quality indicators was noted. The PPS tool provided a convenient, inexpensive surveillance system of antimicrobial consumption and should be considered an essential component to establish and maintain informed antibiotic stewardship in hospitals.
We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven railguns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: ne ≈ ni ~ 1016 cm−3, Te ≈ Ti ≈ 1.4 eV, Vjet ≈ 30–100 km/s, mean charge
≈ 1, sonic Mach number Ms ≡ Vjet/Cs > 10, jet diameter = 5 cm, and jet length ≈20 cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.
The Helicon-Cathode(HelCat) device is a medium-size linear experiment suitable for a wide range of basic plasma science experiments in areas such as electrostatic turbulence and transport, magnetic relaxation, and high power microwave (HPM)-plasma interactions. The HelCat device is based on dual plasma sources located at opposite ends of the 4 m long vacuum chamber – an RF helicon source at one end and a thermionic cathode at the other. Thirteen coils provide an axial magnetic field B ⩾ 0.220 T that can be configured individually to give various magnetic configurations (e.g. solenoid, mirror, cusp). Additional plasma sources, such as a compact coaxial plasma gun, are also utilized in some experiments, and can be located either along the chamber for perpendicular (to the background magnetic field) plasma injection, or at one of the ends for parallel injection. Using the multiple plasma sources, a wide range of plasma parameters can be obtained. Here, the HelCat device is described in detail and some examples of results from previous and ongoing experiments are given. Additionally, examples of planned experiments and device modifications are also discussed.
The photometric observations (UBVRI) of nine cool R Coronae Borealis (RCB) stars have been collected at Mt John University Observatory, New Zealand, over a period of twelve years. The analysis of the magnitude–colour and colour–colour diagrams for the recovery phase demonstrates that all declines exhibit a similar asymptotic approach to their normal brightness. Declines return to maximum brightness along a line with essentially the same slope that does not depend on the star or the depth of the decline. Assuming a uniform obscuration of the photosphere by the dust cloud during the recovery phase, the extinction properties of the material were determined. The ratio of total to selective extinction (RV) for the RCB stars in our sample is in the range 2.5 to 4.6, indicating that the obscuring dust has extinction properties similar to that of the interstellar dust. Observations have been compared with the theoretical extinction curves for different sorts of grains.
Visual perceptual problems are common in Parkinson's disease (PD) and often affect activities of daily living (ADLs). PD patients with non-tremor symptoms at disease onset (i.e., rigidity, bradykinesia, gait disturbance or postural instability) have more diffuse neurobiological abnormalities and report worse non-motor symptoms and functional changes than patients whose initial symptom is tremor, but the relation of motor symptom subtype to perceptual deficits remains unstudied. We assessed visual ADLs with the Visual Activities Questionnaire in 25 non-demented patients with PD, 13 with tremor as the initial symptom and 12 with an initial symptom other than tremor, as well as in 23 healthy control participants (NC). As expected, the non-tremor patients, but not the tremor patients, reported more impairment in visual ADLs than the NC group, including in light/dark adaptation, acuity/spatial vision, depth perception, peripheral vision and visual processing speed. Non-tremor patients were significantly worse than tremor patients overall and on light/dark adaptation and depth perception. Environmental enhancements especially targeted to patients with the non-tremor PD subtype may help to ameliorate their functional disability. (JINS, 2011, 17, 841–852)
Twin studies suggest that global and regional brain volumes are highly heritable. However, estimates of heritability vary across development. Given that all twin studies are open to the potential criticism of non-generalizability due to differences in intrauterine environment between twins and singletons, these age effects may reflect the influence of perinatal environmental factors, which are unique to twins and which may be especially evident early in life. To address this question, we compared brain volumes and the relationship of brain volumes to gestational age in 136 singletons (67 male, 69 female) and 154 twins (75 male, 79 female; 82 DZ, 72 MZ) who had received high resolution MRI scans of the brain in the first month of life. Intracranial volume, total white matter, and ventricle volumes did not differ between twins and singletons. However, cerebrospinal fluid and frontal white matter volume was greater in twins compared to singletons. While gray matter volumes at MRI did not differ between groups, the slope of the relationship between total and cortical gray matter and gestational age at the MRI scan was steeper in MZ twins compared to DZ twins. Post-hoc analyses suggested that gray matter development is delayed in MZ twins in utero and that they experience ‘catch-up’ growth in the first month of life. These differences should be taken into account when interpreting and designing studies in the early postnatal period.
A spectroscopic survey of nearly 700 stars probing the Galactic Thick Disc far from the
Solar neighbourhood is performed. The MATISSE (MATrix Inversion for Spectral SynthEsis)
algorithm is developed and trained in order to automatically obtain atmospheric parameters
of stars. The derived effective temperatures, surface gravities and overall metallicities
are then combined to stellar evolution isochrones, radial velocities and proper motions to
derive the distances, kinematics and orbital parameters of the sample stars. Results are
compared with simulations from the Besançon model of the Milky Way.
Epitaxial thin films of PbZr0.52Ti0.48O3 (PZT) were synthesized successfully on SrRuO3/SrTiO3/MgO/TiN/Si heterostructures by pulsed laser deposition. The films were single phase and had (001) orientation. The deposition parameters were varied to obtain the best epitaxial layer for each of the compounds. Transmission electron microscopy indicated good epitaxy for the entire heterostructure and sharp interfaces between the epilayers. Dielectric and P–E hysteresis loop measurements were carried out with evaporated Ag electrodes. The dielectric constant for the films was found to be between 400–450. The value of saturation polarization Ps was between 55–60 μC/cm2, and the coercive field Ec varied from 60–70 kV/cm. Integration of PZT films with silicon will be useful for future memory and micromechanical devices.
Polymer thick film (PTF) resistors were fabricated using a new laser-based transfer technique called matrix-assisted pulsed laser evaporation direct write (MAPLE-DW). MAPLE-DW is a versatile direct writing technique capable of writing a wide variety of materials on virtually any substrate in air and at room temperature. Epoxy-based PTF resistors spanning four decades of sheet resistances (10 Ω/sq. to 100 kΩ/sq.) were deposited on alumina substrates under ambient conditions. Electrical characteristics of these MAPLE-DW deposited resistors were studied at a wide frequency range (1 MHz to 1.8 GHz), and the results were explained through an equivalent circuit model and impedance spectroscopy. Temperature coefficient of resistance measurements for the PTF resistors were performed between 25 and 125 °C. The results based on the percolation theory were used to explain the temperature dependence of the resistance behavior of the PTF resistors.
Effects of the vicinal angle, film thickness, and temperature on the growth modes, microstructures, and electrical properties of YBa2Cu3O7–δ on SrTiO3 were studied. Island growth transition between the initial nucleation and the later coalescence stages was observed with film thickness on a planar SrTiO3, while no islands were observed at the later stage due to the step-flow mode. As the growth temperature increased, a-axis precipitates were transformed to c-axis precipitates (islands), while no islands formed on vicinal SrTiO3. The supercurrent critical temperature was strongly related to the substrate vicinal angle due to the step-flow mode.
Does incidence of dementia follow the age pattern of prevalence? Is gender a risk factor? Do patterns of incidence differ between dementias?
To assess age-specific incidence rates of undifferentiated dementias, Alzheimer's disease and vascular dementia.
5222 individuals aged $65 years, were interviewed using the Geriatric Mental State/History and Aetiology Schedule. The AGECAT package was used to identify cases at three interviewing waves at two-year intervals. Diagnoses were made using ICD −10 Research Criteria and validated against neurological and psychological examination, with imaging and neuropathology on unselected subsamples.
Incidence rates of the dementias increase with age. Age patterns are similar between Alzheimer's disease and vascular dementia. Gender appears influential in Alzheimer's disease. In England and Wales, 39 437 new cases of Alzheimer's disease (4.9/1000 person-years at risk); 20 513 of vascular dementia (2.6/1000 person-years) and 155 169 of undifferentiated dementia (19/1000 person-years) can be expected each year.
Incidence rates for Alzheimer's disease and vascular dementia appear to behave differently with an increased risk of Alzheimer's disease for women compared to vascular dementia.
Risk factors of depression in later life, particularly for sub-cases and for psychotic and neurotic types of depression, are unclear.
To identify such risk factors.
Over 5200 older people ($65 years), randomly selected from Liverpool, were interviewed using the Geriatric Mental State (GMS)and the Minimum Data Set (MDS). The computer-assisted diagnosis AGECAT identified 483 cases and 575 sub-cases of depression and 2451 with no mental problems. Logistic regression was employed to examine factors relevant to caseness.
In multiple logistical regression, odds ratios (ORs) were significantly high for being female (2.04, 95% CI 1.56–2.69), widowed (2.00, 1.18–3.39), having alcohol problems (4.37, 1.40–2.94), physical disablement (2.03, 1.40–2.94), physical illness (1.98,.1.25–3.15), taking medications to calm down (10.04, 6.41 −15.71), and dissatisfaction with life (moderate 4.54, 3.50–5.90; more severe 29.00, 16.00–52.59). Good social networks reduced the ORs. If sub-cases were included as controls, the statistical significance was reduced.
Age was not associated with depression in later life whereas gender, physical disablement and dissatisfaction with life were. The sub-cases shared many risk factors with cases, suggesting that prevention may need to be attempted at an early stage.
A newly-developed technique for the simultaneos characterization of the oxide-silicon interface properties and of bulk impurities was used for a systematic study of the nitridation process of thin oxides. This technique is based upon surface recombination velocity measurements, and does not require the formation of a capacitor structure, so it is very suitable for the characterization of as-grown interfaces.
Oxides grown both in dry and in wet enviroments were considered, and nitridation processes in N2O and in NO were compared to N2 annealing processes. The effect of nitridation temperature and duration were also studied, and RTO/RTN processes were compared to conventional furnace nitridation processes.
Surface recombination velocity was correlated with nitrogen concentration at the oxide-silicon interface obtained by Secondary Ion Mass Spectroscopy (SIMS) measurements. Surface recombination velocity (hence surface state density) decreases with increasing nitrogen pile-up at the oxide-silicon interface, indicating that in nitrided interfaces surface state density is limited by nitridation. NO treatments are much more effective than N2O treatments in the formation of a nitrogen-rich interface layer and, as a consequence, in surface state reduction.
Surface state density was measured in fully processed wafers before and after constant current stress. After a complete device process surface states are annealed out by hydrogen passivation, however they are reactivated by the electrical stress, and surface state results after stress were compared with data of surface recombination velocity in as-processed wafers.
A key to the ultimate technological applications of core-shell nanoparticle materials is the understanding of the structure-property correlation. This work focuses on the characterizations of the structural properties for composite thin films derived from gold nanoparticles and thiolates using infrared reflectance spectroscopic (IRS) and electron spin resonance (ESR) techniques. IRS provides information on molecular packing and ordering of the shell components in the films, which relates to the molecular interactions and interfacial reactivities. ESR probes the conduction electron spin resonance properties of the nanosized cores, which can be correlated with the network or environmental electronic effects on the crystal cores. Results are discussed in terms of their correlation with the nanoparticle core sizes and the organic shell functionality.