2,332 research outputs found
Bounded rationality and valuation
A computational valuation model is developed to predict discrepancies between choices and valuations in economic experiments. The model is based on Boundedly Rational Expected Utility Theory (Navarro-Martinez et al., 2017) and predicts average certainty equivalents for monetary lotteries that are higher than choices would imply from the same set of underlying preferences. Thereby, the model predicts the preference reversal phenomenon (Slovic and Lichtenstein, 1968).
The model predicts that a choice between a lottery and a sure payoff can influence a subsequent money valuation of the choice’s strength of preference. This monetary strength of preference (MSoP), can be positively affected by spill-over effects from the choice process and also by consistency-seeking behaviour towards information about the choice. This can explain observations by Butler et al. (2014a) that participants systematically state MSoP values that are too high relative to their choices. Model simulations show how this model differs from existing computational valuation models. When adapted to predict MSoP values, these instead predict a negative MSoP mismatch.
These predictions are tested in a laboratory experiment, which finds a positive MSoP mismatch but only when MSoP values stem from upward adjustments to a sure amount. When sure amounts are adjusted downwards, a negative MSoP mismatch occurs instead. Neither the novel model nor existing theory can explain this two-fold pattern. Controlling for the delay between choices and MSoP valuations also rules out the possibility of spill-over effects.
Participants also value lotteries too high relative to their choice behaviour. Contrary to theory, a reaction time analysis shows that individually-longer reaction times do not reduce discrepancies between valuations and choice data. Preference reversals do not become less frequent when participants deliberate for longer.
Altogether, these results show novel and yet unexplained phenomena in valuation behaviour but also highlight how theory needs to be adapted to explain these
Leguminosenkörnerschrote und andere vegetabile Dünger im Ökologischen Gemüsebau
The potential of different plant based organic fertilisers (PBOF) to substitute animal based organic fertilisers (ABOF) in organic vegetable production were investigated in incubation, pot and field experiments. PBOFs have the potential to replace ABOFs. Particularly legume seed meals show fast net N-release even at low soil temperatures. Considerable differences in nitrate contents of vegetables can be found between the different fertilisers although fresh matter and N yields are nearly identical
Surface concentration dependent structures of iodine on Pd(110)
We use photoelectron spectroscopy, low energy electron diffraction, scanning tunneling microscopy, and density functional theory to investigate coverage dependent iodine structures on Pd(110). At 0.5 ML (monolayer), a c(2 × 2) structure is formed with iodine occupying the four-fold hollow site. At increasing coverage, the iodine layer compresses into a quasi-hexagonal structure at 2/3 ML, with iodine occupying both hollow and long bridge positions. There is a substantial difference in electronic structure between these two iodine sites, with a higher electron density on the bridge bonded iodine. In addition, numerous positively charged iodine near vacancies are found along the domain walls. These different electronic structures will have an impact on the chemical properties of these iodine atoms within the layer
Point-of-care method for total white cell count: an evaluation of the HemoCue WBC device
Point-of-care testing (POCT) is becoming an important adjunct to haematology laboratory practice. An important component of the blood count is the total white cell count (WBC). Previously, this required laborious microscopic cell counting, but it can now be performed by means of automation; however, in many under-resourced countries, costly automated counters are only available in very few central hospitals. Moreover, neither method is practical in most POCT situations. The HemoCue WBC has been developed as a simplified alternative method, consisting of a reagent pre-loaded disposable cuvette together with basic image analysis technology. This report describes an assessment of its utility. The WBC of 500 routine blood samples from the hospital were tested in parallel by the HemoCue WBC and by a reference analyser to assess accuracy and utility of the former. The tests included precision, linearity, type of blood sample and anticoagulant and potential interfering substances in blood specimens. In the tests for accuracy, 192 of the 200 showed percentage difference from the NEQAS reference of <10% whilst the remaining eight samples differed by <12%, thus meeting the requirements of Clinical laboratory improvement amendments (CLIA)-88 regulations. Of the samples tested with potential interfering substances only those with >2% normoblasts or reticulocytosis showed significant differences from the reference measurements. The HemoCue WBC is reliable for WBC counts within the analytical range of 0.4–30.0 × 109/l, except in samples where there are significant numbers of normoblasts or reticulocytes. It is simple to use and provides a valuable advance in the facilities available for POCT in haematology
Disorder, inhomogeneity and spin dynamics in f-electron non-Fermi liquid systems
Muon spin rotation and relaxation (SR) experiments have yielded evidence
that structural disorder is an important factor in many f-electron-based
non-Fermi-liquid (NFL) systems. Disorder-driven mechanisms for NFL behaviour
are suggested by the observed broad and strongly temperature-dependent SR
(and NMR) linewidths in several NFL compounds and alloys. Local disorder-driven
theories (Kondo disorder, Griffiths-McCoy singularity) are, however, not
capable of describing the time-field scaling seen in muon spin relaxation
experiments, which suggest cooperative and critical spin fluctuations rather
than a distribution of local fluctuation rates. A strong empirical correlation
is established between electronic disorder and slow spin fluctuations in NFL
materialsComment: 24 pages, 15 figures, submitted to J. Phys.: Condens. Matte
Non-Invasive Measurement of Hemoglobin: Assessment of Two Different Point-of-Care Technologies
Measurement of blood hemoglobin (Hb) concentration is a routine procedure. Using a non-invasive point-of-care device reduces pain and discomfort for the patient and allows time saving in patient care. The aims of the present study were to assess the concordance of Hb levels obtained non-invasively with the Pronto-7 monitor (version 2.1.9, Masimo Corporation, Irvine, USA) or with the NBM-200MP monitor (Orsense, Nes Ziona, Israel) and the values obtained from the usual colorimetric method using blood samples and to determine the source of discordance.We conducted two consecutive prospective open trials enrolling patients presenting in the emergency department of a university hospital. The first was designed to assess Pronto-7™ and the second NBM-200MP™. In each study, the main outcome measure was the agreement between both methods. Independent factors associated with the bias were determined using multiple linear regression. Three hundred patients were prospectively enrolled in each study. For Pronto-7™, the absolute mean difference was 0.56 g.L(-1) (95% confidence interval [CI] 0.41 to 0.69) with an upper agreement limit at 2.94 g.L(-1) (95% CI [2.70;3.19]), a lower agreement limit at -1.84 g.L(-1) (95% CI [-2.08;-1.58]) and an intra-class correlation coefficient at 0.80 (95% CI [0.74;0.84]). The corresponding values for the NBM-200MP™ were 0.21 [0.02;0.39], 3.42 [3.10;3.74], -3.01 [-3.32;-2.69] and 0.69 [0.62;0.75]. Multivariate analysis showed that age and laboratory values of hemoglobin were independently associated with the bias when using Pronto-7™, while perfusion index and laboratory value of hemoglobin were independently associated with the bias when using NBM-200MP™.Despite a relatively limited bias in both cases, the large limits of agreement found in both cases render the clinical usefulness of such devices debatable. For both devices, the bias is independently and inversely associated with the true value of hemoglobin.ClinicalTrials.gov NCT01321580 and NCT01321593
SWITCH : A randomised, sequential, open-label study to evaluate the efficacy and safety of Sorafenib-sunitinib versus Sunitinib-sorafenib in the treatment of metastatic renal cell cancer
Background
Understanding how to sequence targeted therapies for metastatic renal
cell carcinoma (mRCC) is important for maximisation of clinical benefit.
Objectives
To prospectively evaluate sequential use of the multikinase inhibitors sorafenib followed by sunitinib (So-Su) versus sunitinib followed by sorafenib (Su-So) in patients with mRCC.
Design, setting, and participants
The multicentre, randomised, open-label, phase 3 SWITCH study assessed So-Su versus Su-So in patients with mRCC without prior systemic therapy, and stratified by Memorial Sloan Kettering Cancer Center risk score (favourable or intermediate).
Intervention
Patients were randomised to sorafenib 400 mg twice daily followed, on progression or intolerable toxicity, by sunitinib 50 mg once daily (4 wk on, 2 wk off) (So-Su), or vice versa (Su-So).
Outcome measurements and statistical analysis
The primary endpoint was improvement in progression-free survival (PFS) with So-Su versus Su-So, assessed from randomisation to progression or death during second-line therapy. Secondary endpoints included overall survival (OS) and safety.
Results and limitations
In total, 365 patients were randomised (So-Su, n = 182; Su-So, n = 183). There was no significant difference in total PFS between So-Su and Su-So (median 12.5 vs 14.9 mo; hazard ratio [HR] 1.01; 90% confidence interval [CI] 0.81–1.27; p = 0.5 for superiority). OS was similar for So-Su and Su-So (median 31.5 and 30.2 mo; HR 1.00, 90% CI 0.77–1.30; p = 0.5 for superiority). More So-Su patients than Su-So patients reached protocol-defined second-line therapy (57% vs 42%). Overall, adverse event rates were generally similar between the treatment arms. The most frequent any-grade treatment-emergent first-line adverse events were diarrhoea (54%) and hand-foot skin reaction (39%) for sorafenib; and diarrhoea (40%) and fatigue (40%) for sunitinib.
Conclusions
Total PFS was not superior with So-Su versus Su-So. These results demonstrate that sorafenib followed by sunitinib and vice versa provide similar clinical benefit in mRCC
A study of the metal binding capacity of saccharinic acids formed during the alkali catalysed decomposition of cellulosic materials: nickel complexation by glucoisosaccharinic acids and xyloisosaccharinic acids
The stoichiometry of the metal complexes formed between nickel and the ligand β-glucoisosaccharinic acid (β-GISA) and a racemic mixture of enantiomers of xyloisosaccharinic acid (XISA) has been determined at both neutral and alkaline pHs. Bjerrum plots, Job's plots and conductance measurements indicated that for each of the systems one to one Ni(ligand) complexes were formed at near neutral pHs (13) sparingly soluble Ni2(ligand)(OH)4 complexes were formed. The stability constants for the Ni(β-GISA), Ni(α-GISA) and Ni(XISA) complexes formed at neutral pH were determined under identical conditions using polarographic studies. The measured stability constants for Ni(β-GISA) (log10 β = 1.94 ± 0.15) and for Ni(α-GISA)(log10 β = 2.07 ± 0.13) are very similar; the value measured for the Ni(XISA) complex (log10 β = 0.83) was an order of magnitude smaller. The stability constants for the Ni2(Ligand)(OH)4 complexes formed at highly alkaline pHs were determined using the Schubert method. The measured stability constant for Ni2(β-GISA)(OH)4 (log10 β = 30.6 ± 0.5) was an order of magnitude bigger than the value for Ni2(α-GISA)(OH)4 (log10 β = 29.0 ± 0.5) measured under identical conditions. Attempts to measure the stability constant for Ni2(XISA)(OH)4 were unsuccessful; Ni2(XISA)(OH)4 complexes were not present in significant amounts at high pH to allow the log10β value to be determined by the Schubert method
Biochemical Characterization of APPL Endosomes: The Role of Annexin A2 in APPL Membrane Recruitment
APPL endosomes are a recently identified subpopulation of early endosomes characterized by the presence of two homologous Rab5 effector proteins APPL1 and APPL2. They exhibit only limited colocalization with EEA1, another Rab5 effector and a marker of the canonical early endosomes. Although APPL endosomes appear to play important roles in cargo trafficking and signal transduction, their protein composition and biochemical properties remain largely unknown. Here we employed membrane fractionation methods to characterize APPL endosomes biochemically. We demonstrate that they represent heterogeneous membrane structures which can be discriminated from the canonical EEA1-positive early endosomes by their partly different physical properties and a distinct migration pattern in the continuous density gradients. In search for other potential markers of APPL endosomes we identified Annexin A2 as an interacting partner of both APPL1 and APPL2. Annexin A2 is a Ca2+ and phosphatidylinositol 4,5-bisphosphate binding protein, previously implicated in several endocytic steps. We show that Annexin A2 co-fractionates and colocalizes with APPL endosomes. Moreover, silencing of its expression causes solubilization of APPL2 from endosomes. Although Annexin A2 is not an exclusive marker of APPL endosomes, our data suggest that it has an important function in membrane recruitment of APPL proteins, acting in parallel to Rab5
The Society for Immunotherapy of Cancer statement on best practices for multiplex immunohistochemistry (IHC) and immunofluorescence (IF) staining and validation.
OBJECTIVES: The interaction between the immune system and tumor cells is an important feature for the prognosis and treatment of cancer. Multiplex immunohistochemistry (mIHC) and multiplex immunofluorescence (mIF) analyses are emerging technologies that can be used to help quantify immune cell subsets, their functional state, and their spatial arrangement within the tumor microenvironment.
METHODS: The Society for Immunotherapy of Cancer (SITC) convened a task force of pathologists and laboratory leaders from academic centers as well as experts from pharmaceutical and diagnostic companies to develop best practice guidelines for the optimization and validation of mIHC/mIF assays across platforms.
RESULTS: Representative outputs and the advantages and disadvantages of mIHC/mIF approaches, such as multiplexed chromogenic IHC, multiplexed immunohistochemical consecutive staining on single slide, mIF (including multispectral approaches), tissue-based mass spectrometry, and digital spatial profiling are discussed.
CONCLUSIONS: mIHC/mIF technologies are becoming standard tools for biomarker studies and are likely to enter routine clinical practice in the near future. Careful assay optimization and validation will help ensure outputs are robust and comparable across laboratories as well as potentially across mIHC/mIF platforms. Quantitative image analysis of mIHC/mIF output and data management considerations will be addressed in a complementary manuscript from this task force
- …