440 research outputs found
The intensity and motion of hybrid cyclones in the Australian region in a composite potential vorticity framework
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordHybrid cyclones (HCs) in the Australian region typically reach their peak intensity in an amplified flow comprising upperâtropospheric ridges upstream and downstream of the cyclone and a northâsouth elongated trough. Nonetheless, there is considerable caseâtoâcase variability. Taking a composite viewpoint, the present study investigates how such variations in the upperâtropospheric potential vorticity (PV) anomalies affect the subsequent intensity and motion of HCs in the Australian region. First, cyclones are grouped into four clusters with structurallyâsimilar environments through a kâmeans clustering of the 315âK PV anomaly. The clusters reveal that HCs can be associated with a northâsouth elongated trough (Cluster 1), a PV cutâoff (Cluster 2), and cyclonically breaking troughs (Clusters 3 and 4). Second, the effect of these features on the intensity and tracks is quantified using piecewise PV inversion. The maximum intensity of cyclones in Cluster 1 is largely determined by their upperâtropospheric cyclonic PV anomaly. Conversely, diabatically generated lowerâtropospheric PV anomalies dominate the intensity of cyclones in Clusters 3 and 4. In these two clusters, the cyclonically breaking trough and a downstream ridge induce an anomalous northeasterly lowâlevel flow across the cyclone centre. The downstream ridge is most pronounced in Cluster 4, leading to the greatest poleward cyclone displacement compared to the other clusters. In Clusters 1 and 2, the upperâlevel PV anomaly primarily slows the eastward motion of the cyclones. In agreement with recent idealised studies, the analysis suggests that the effect of upperâtropospheric PV anomalies on the poleward motion of HCs is analogous to the betaâgyres that influence the motion of tropical cyclones.Helmholtz-AssociationAustralian Research Council Centre of Excellence for Climate ExtremesAustralian Research Counci
Synoptic climatology of hybrid cyclones in the Australian region
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordâŻIn May and September 2016, two intense hybrid cyclones (HCs) developed over the Great Australian Bight damaging infrastructure and causing a stateâwide power outage in South Australia. These two cyclones motivate the compilation of the first synoptic climatology of HCs in the Australian region, including an analysis of their importance for wind and precipitation extremes, and a composite view of the largeâscale flow in which they develop. HCs are identified in ERAâInterim data from 1979 to 2010 using an objective feature tracking method and a cyclone phase space diagnostic. HCs exhibit a pronounced seasonal cycle with most of them occurring from May to September. During these months, HCs are most frequent over the Tasman Sea and the Great Australian Bight where they account for 50% of all cyclones. A common characteristic of all HCs is that the strongest precipitation, which is locally extreme in 91% of all HCs, falls in the warmâsector and along a bentâback warm front on the poleward side of the cyclones. Moreover, the area affected by extreme precipitation and the maximum precipitation in HCs are no different from nonâhybrid cyclones (NHCs). In contrast, the area affected by extreme wind gusts is significantly larger in HCs than for NHCs. In both HCs and NHCs the strongest nearâsurface wind gusts typically occur in the cold air mass in the wake of the cyclones, especially in those over the Great Australian Bight. The upperâtropospheric structure of HCs is characterised by an elongated cyclonic potential vorticity anomaly embedded between two ridges that eventually cuts off. In contrast, NHCs are characterised by a zonal flow upstream and upperâtropospheric cyclonic wave breaking.Helmholtz-AssociationAustralian Research Council Centre of Excellence for Climate ExtremesAustralian Research Counci
On the Relationship Between the MaddenâJulian Oscillation and the Hadley and Walker Circulations
This study investigates: (i) how the local meridional (Hadley) and zonal (Walker) circulations change in each phase of the MaddenâJulian Oscillation (MJO); and (ii) the effect of enhanced and suppressed MJOârelated convection on the poleward extent of the local Hadley circulations and, thus, the strengths and positions of the subtropical jets. We examine these effects in ERAâInterim reanalysis by decomposing the vertical mass flux into zonal and meridional components. We show for the first time, that as the envelope of enhanced convection moves eastwards from Africa to the Central Pacific the local Hadley circulation is enhanced. The regional Walker circulation in the Pacific is strengthened when the envelope of active MJO convection is located over the Maritime Continent and weakened when the region of suppressed convection is located there. In regions of anomalous upperâlevel divergence the subtropical jet is enhanced. The core of the subtropical jet over Asia shifts eastwards with the progression of the MJO and shifts farther poleward in regions of anomalous upperâlevel divergence linked with enhanced convection. The region of either enhanced or suppressed convection over the Maritime Continent strengthens or weakens the local Hadley circulation, producing disturbances in the subtropical jet. These disturbances then force midlatitude Rossby waves that propagate across the Pacific Ocean in both hemispheres
Trends in the local Hadley and local Walker circulations
The linear trend in the local Hadley and Walker circulations from 1979 to 2009 is calculated. These local circulations are defined through a decomposition of the vertical mass flux into its zonal and meridional components. Defining the local circulation this way ensures that the two orthogonal circulations (the local Hadley and Walker circulations) sum to the original circulation even after averaging the circulations regionally. Large regional differences in changes in the local Hadley and Walker circulations over a 31 year period are found. For example, the local Hadley circulation has shifted southward over Africa, the Maritime Continent, and the western and central Pacific by about 1°. Over the Americas and the Atlantic the local Hadley circulation has strengthened by about 1-5%. The zonal component of the vertical mass flux has increased by about 10-20% in the tropics over all continents and decreased over the adjacent oceans by about 10-20%. Although the local Walker circulations in the Indian Ocean and the Atlantic have weakened, the circulation in the Pacific has changed little (about 1-2%). The local Walker circulations in all ocean basins have shifted westward by about 1-2°on average
Beliefs about bad people are volatile
People form moral impressions rapidly, effortlessly and from a remarkably young age1,2,3,4,5. Putatively \u2018bad\u2019 agents command more attention and are identified more quickly and accurately than benign or friendly agents5,6,7,8,9,10,11,12. Such vigilance is adaptive, but can also be costly in environments where people sometimes make mistakes, because incorrectly attributing bad character to good people damages existing relationships and discourages forming new relationships13,14,15,16. The ability to accurately infer the moral character of others is critical for healthy social functioning, but the computational processes that support this ability are not well understood. Here, we show that moral inference is explained by an asymmetric Bayesian updating mechanism in which beliefs about the morality of bad agents are more uncertain (and therefore more volatile) than beliefs about the morality of good agents. This asymmetry seems to be a property of learning about immoral agents in general, as we also find greater uncertainty for beliefs about the non-moral traits of bad agents. Our model and data reveal a cognitive mechanism that permits flexible updating of beliefs about potentially threatening others, a mechanism that could facilitate forgiveness when initial bad impressions turn out to be inaccurate. Our findings suggest that negative moral impressions destabilize beliefs about others, promoting cognitive flexibility in the service of cooperative but cautious behaviour
Influence of design and material characteristics on 3D printed flow-cells for heat transfer-based analytical devices
Redesigning 3D-printed flow cells is reported used for heat transfer based detection of biomolecules from a flow-through system to an addition-type measurement cell. The aim of this study is to assess the performance of this new measurement design and critically analyse the influence of material properties and 3D printing approach on thermal analysis. Particular attention is paid to reduce the time to stabilisation, the sample volume in order to make the technique suitable for clinical applications, and improving the sensitivity of the platform by decreasing the noise and interference of air bubbles. The three different approaches that were studied included a filament polylactic acid cell using only fused filament fabrication (FFF), a resin cell printed using stereolitography (SLA), and finally a design made of copper, which was manufactured by combining metal injection moulding (MIM) with fused filament fabrication (FFF). Computational fluid dynamic (CFD) modelling was undertaken using ANSYS Fluent V18.1 to provide insight into the flow of heat within the measurement cell, facilitating optimisation of the system and theoretical response speed. It was shown that the measurement cells using SLA had the lowest noise (~ 0.6%) and shortest measurement time (15 min), whereas measurement cells produced using other approaches had lower specificity or suffered from voiding issues. Finally, we assessed the potential of these new designs for detection of biomolecules and amoxicillin, a commonly used beta lactam antibiotic, to demonstrate the proof of concept. It can be concluded that the resin addition-type measurement cells produced with SLA are an interesting affordable alternative, which were able to detect amoxicillin with high sensitivity and have great promise for clinical applications due to the disposable nature of the measurement cells in addition to small sample volumes
Defining seasonal marine microbial community dynamics
Here we describe, the longest microbial time-series analyzed to date using high-resolution 16S rRNA tag pyrosequencing of samples taken monthly over 6 years at a temperate marine coastal site off Plymouth, UK. Data treatment effected the estimation of community richness over a 6-year period, whereby 8794 operational taxonomic units (OTUs) were identified using single-linkage preclustering and 21â130 OTUs were identified by denoising the data. The Alphaproteobacteria were the most abundant Class, and the most frequently recorded OTUs were members of the Rickettsiales (SAR 11) and Rhodobacteriales. This near-surface ocean bacterial community showed strong repeatable seasonal patterns, which were defined by winter peaks in diversity across all years. Environmental variables explained far more variation in seasonally predictable bacteria than did data on protists or metazoan biomass. Change in day length alone explains >65% of the variance in community diversity. The results suggested that seasonal changes in environmental variables are more important than trophic interactions. Interestingly, microbial association network analysis showed that correlations in abundance were stronger within bacterial taxa rather than between bacteria and eukaryotes, or between bacteria and environmental variables
TP53 abnormalities correlate with immune infiltration and associate with response to flotetuzumab immunotherapy in AML
Somatic TP53 mutations and 17p deletions with genomic loss of TP53 occur in 37% to 46% of acute myeloid leukemia (AML) with adverse-risk cytogenetics and correlate with primary induction failure, high risk of relapse, and dismal prognosis. Herein, we aimed to characterize the immune landscape of TP53-mutated AML and determine whether TP53 abnormalities identify a patient subgroup that may benefit from immunotherapy with flotetuzumab, an investigational CD123 Ă CD3 bispecific dual-affinity retargeting antibody (DART) molecule. The NanoString PanCancer IO360 assay was used to profile 64 diagnostic bone marrow (BM) samples from patients with TP53-mutated (n = 42) and TP53-wild-type (TP53-WT) AML (n = 22) and 45 BM samples from patients who received flotetuzumab for relapsed/refractory (R/R) AML (15 cases with TP53 mutations and/or 17p deletion). The comparison between TP53-mutated and TP53-WT primary BM samples showed higher expression of IFNG, FOXP3, immune checkpoints, markers of immune senescence, and phosphatidylinositol 3-kinase-Akt and NF-ÎșB signaling intermediates in the former cohort and allowed the discovery of a 34-gene immune classifier prognostic for survival in independent validation series. Finally, 7 out of 15 patients (47%) with R/R AML and TP53 abnormalities showed complete responses to flotetuzumab (less than 5% BM blasts) on the CP-MGD006-01 clinical trial (NCT #02152956) and had significantly higher tumor inflammation signature, FOXP3, CD8, inflammatory chemokine, and PD1 gene expression scores at baseline compared with nonresponders. Patients with TP53 abnormalities who achieved a complete response experienced prolonged survival (median, 10.3 months; range, 3.3-21.3 months). These results encourage further study of flotetuzumab immunotherapy in patients with TP53-mutated AML
Perceptual expertise improves category detection in natural scenes
There is much debate about how detection, categorization, and within-category identification relate to one another during object recognition. Whether these tasks rely on partially shared perceptual mechanisms may be determined by testing whether training on one of these tasks facilitates performance on another. In the present study we asked whether expertise in discriminating objects improves the detection of these objects in naturalistic scenes. Self-proclaimed car experts (N = 34) performed a car discrimination task to establish their level of expertise, followed by a visual search task where they were asked to detect cars and people in hundreds of photographs of natural scenes. Results revealed that expertise in discriminating cars was strongly correlated with car detection accuracy. This effect was specific to objects of expertise, as there was no influence of car expertise on person detection. These results indicate a close link between object discrimination and object detection performance, which we interpret as reflecting partially shared perceptual mechanisms and neural representations underlying these tasks: the increased sensitivity of the visual system for objects of expertise â as a result of extensive discrimination training â may benefit both the discrimination and the detection of these objects. Alternative interpretations are also discussed
Drug waste minimisation and cost-containment in Medical Oncology: Two-year results of a feasibility study
<p>Abstract</p> <p>Background</p> <p>Cost-containment strategies are required to face the challenge of rising drug expenditures in Oncology. Drug wastage leads to economic loss, but little is known about the size of the problem in this field.</p> <p>Methods</p> <p>Starting January 2005 we introduced a day-to-day monitoring of drug wastage and an accurate assessment of its costs. An internal protocol for waste minimisation was developed, consisting of four corrective measures: 1. A rational, per pathology distribution of chemotherapy sessions over the week. 2. The use of multi-dose vials. 3. A reasonable rounding of drug dosages. 4. The selection of the most convenient vial size, depending on drug unit pricing.</p> <p>Results</p> <p>Baseline analysis focused on 29 drugs over one year. Considering their unit price and waste amount, a major impact on expense was found to be attributable to six drugs: cetuximab, docetaxel, gemcitabine, oxaliplatin, pemetrexed and trastuzumab. The economic loss due to their waste equaled 4.8% of the annual drug expenditure. After the study protocol was started, the expense due to unused drugs showed a meaningful 45% reduction throughout 2006.</p> <p>Conclusion</p> <p>Our experience confirms the economic relevance of waste minimisation and may represent a feasible model in addressing this issue.</p> <p>A centralised unit of drug processing, the availability of a computerised physician order entry system and an active involvement of the staff play a key role in allowing waste reduction and a consequent, substantial cost-saving.</p
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