We experimentally determine weak values for a single photon's polarization, obtained via a weak measurement that employs a two-photon entangling operation, and postselection. The weak values cannot ...be explained by a semiclassical wave theory, due to the two-photon entanglement. We observe the variation in the size of the weak value with measurement strength, obtaining an average measurement of the S1 Stokes parameter more than an order of magnitude outside of the operator's spectrum for the smallest measurement strengths.
We demonstrate complete characterization of a two-qubit entangling process--a linear optics controlled-NOT gate operating with coincident detection--by quantum process tomography. We use a ...maximum-likelihood estimation to convert the experimental data into a physical process matrix. The process matrix allows an accurate prediction of the operation of the gate for arbitrary input states and a calculation of gate performance measures such as the average gate fidelity, average purity, and entangling capability of our gate, which are 0.90, 0.83, and 0.73, respectively.
Although the strengths of optical nonlinearities available experimentally have been rapidly increasing in recent years, significant challenges remain to using such nonlinearities to produce useful ...quantum devices such as efficient optical Bell state analyzers or universal quantum optical gates. Here we describe a new approach that avoids the current limitations by combining strong nonlinearities with active Gaussian operations in efficient protocols for Bell state analyzers and controlled-sign gates.
Fungi on the skin: dermatophytes and Malassezia White, Theodore C; Findley, Keisha; Dawson, Jr, Thomas L ...
Cold Spring Harbor perspectives in medicine,
08/2014, Volume:
4, Issue:
8
Journal Article
Peer reviewed
Open access
Several human skin diseases and disorders are associated with two groups of fungi, the dermatophytes and Malassezia. Although these skin-related problems are not generally life threatening, they are ...among the most common diseases and disorders of mankind. These fungi are phylogenetically divergent, with the dermatophytes within the Ascomycota and Malassezia within Basidiomycota. Genome analysis indicates that the adaptations to the skin environment are different in these two groups of fungi. Malassezia are dependent on host lipids and secrete lipases and phospholipases that likely release host fatty acids. The dermatophytes encode multiple enzymes with potential roles in modulating host interactions: polyketide synthases, nonribosomal peptide synthetases, LysM, proteases, kinases, and pseudokinases. These two fungal groups have maximized their interactions with the host using two very different mechanisms.
•Over 120 downwind landfill methane emission transects undertaken.•Monitoring successful between 2000 and 6700 m downwind.•Negative correlation between wind speed and emissions.•Tracer gas technique ...used to estimate methane emissions from gas engine.•About 69% methane capture and recovery.
The methane emissions from a landfill in south-east, UK were successfully quantified during a six-day measurement campaign using the tracer dispersion method. The fair weather conditions made it necessary to perform measurements in the late afternoon and in the evening when the lower solar flux resulted in a more stable troposphere with a lower inversion layer. This caused a slower mixing of the gasses, but allowed plume measurements up to 6700 m downwind from the landfill. The average methane emission varied between 217 ± 14 and 410 ± 18 kg h−1 within the individual measurement days, but the measured emission rates were higher on the first three days (333 ± 27, 371 ± 42 and 410 ± 18 kg h−1) compared to the last three days (217 ± 14, 249 ± 20 and 263 ± 22 kg h−1). It was not possible to completely isolate the extent to which these variations were a consequence of measuring artefacts, such as wind/measurement direction and measurement distance, or from an actual change in the fugitive emission. Such emission change is known to occur with changes in the atmospheric pressure. The higher emissions measured during the first three days of the campaign were measured during a period with an overall decrease in atmospheric pressure (from approximately 1014 mbar on day 1 to 987 mbar on day 6). The lower emissions measured during the last three days of the campaign were carried out during a period with an initial pressure increase followed by a period of slowly reducing pressure. The average daily methane recovery flow varied between 633 and 679 kg h−1 at STP (1 atm, 0 °C). The methane emitted to the atmosphere accounted for approximately 31% of the total methane generated, assuming that the methane generated is the sum of the methane recovered and the methane emitted to the atmosphere, thus not including a potential methane oxidation in the landfill cover soil.
Summary
We re‐analysed prospective data collected by anaesthetists in the Anaesthesia Sprint Audit of Practice (ASAP‐1) to describe associations with linked outcome data. Mortality was 165/11,085 ...(1.5%) 5 days and 563/11,085 (5.1%) 30 days after surgery and was not associated with anaesthetic technique (general vs. spinal, with or without peripheral nerve blockade). The risk of death increased as blood pressure fell: the odds ratio (95% CI) for mortality within five days after surgery was 0.983 (0.973–0.994) for each 5 mmHg intra‐operative increment in systolic blood pressure, p = 0.0016, and 0.980 (0.967–0.993) for each mmHg increment in mean pressure, p = 0.0039. The equivalent odds ratios (95% CI) for 30‐day mortality were 0.968 (0.951–0.985), p = 0.0003 and 0.976 (0.964–0.988), p = 0.0001, respectively. The lowest systolic blood pressure after intrathecal local anaesthetic relative to before induction was weakly correlated with a higher volume of subarachnoid bupivacaine: r2 −0.10 and −0.16 for hyperbaric and isobaric bupivacaine, respectively. A mean 20% relative fall in systolic blood pressure correlated with an administered volume of 1.44 ml hyperbaric bupivacaine. Future research should focus on refining standardised anaesthesia towards administering lower doses of spinal (and general) anaesthesia and maintaining normotension.
☛ CPD available at http://www.learnataagbi.org
We have constructed de novo a high-resolution genetic map that includes the largest set, to our knowledge, of polymorphic markers (
N=14,759) for which genotype data are publicly available; that ...combines genotype data from both the Centre d'Etude du Polymorphisme Humain (CEPH) and deCODE pedigrees; that incorporates single-nucleotide polymorphisms; and that also incorporates sequence-based positional information. The position of all markers on our map is corroborated by both genomic sequence and recombination-based data. This specific combination of features maximizes marker inclusion, coverage, and resolution, making this map uniquely suitable as a comprehensive resource for determining genetic map information (order and distances) for any large set of polymorphic markers.
•Use Gaussian dispersion models to plan tracer gas dispersion campaigns for landfill.•Understand relationship between plume mixing and measurement error before campaign.•Differences in vertical ...mixing in the source/tracer plume causes measurement error.•Place tracer release points parallel to wind direction in idealised situation.•Optimal wind speed for TDM campaigns is between ∼ 4 and 8 m/s.
The measurement of methane emissions from landfills is important to the understanding of landfills’ contribution to greenhouse gas emissions. The Tracer Dispersion Method (TDM) is becoming widely accepted as a technique, which allows landfill emissions to be quantified accurately provided that measurements are taken where the plumes of a released tracer-gas and landfill-gas are well-mixed. However, the distance at which full mixing of the gases occurs is generally unknown prior to any experimental campaign.
To overcome this problem the present paper demonstrates that, for any specific TDM application, a simple Gaussian dispersion model (AERMOD) can be run beforehand to help determine the distance from the source at which full mixing conditions occur, and the likely associated measurement errors. An AERMOD model was created to simulate a series of TDM trials carried out at a UK landfill, and was benchmarked against the experimental data obtained. The model was used to investigate the impact of different factors (e.g. tracer cylinder placements, wind directions, atmospheric stability parameters) on TDM results to identify appropriate experimental set ups for different conditions.
The contribution of incomplete vertical mixing of tracer and landfill gas on TDM measurement error was explored using the model. It was observed that full mixing conditions at ground level do not imply full mixing over the entire plume height. However, when full mixing conditions were satisfied at ground level, then the error introduced by variations in mixing higher up were always less than 10%.
PDF
