How Should Monetary Policy Respond to Asset-Price Bubbles?

We present a simple macroeconomic model that includes a role for an asset-price bubble. We then derive optimal monetary policy settings for two policymakers: a skeptic, for whom the best forecast of future asset prices is the current price; and an activist, whose policy recommendations take into account the complete stochastic implications of the bubble. We show that the activist’s recommendations depend sensitively on the detailed stochastic properties of the bubble. In some circumstances the activist clearly recommends tighter policy than the skeptic, but in others the appropriate recommendation is to be looser. Our results highlight the stringent informational requirements inherent in an activist policy approach to handling asset-price bubbles.

How Should Monetary Policy Respond to Asset-price Bubbles?

We present a simple model of the macroeconomy that includes a role for an asset-price bubble, and derive optimal monetary policy settings for two policy-makers. The first policy-maker, a sceptic, does not attempt to forecast the future possible paths for the asset-price bubble when setting policy. The second policy-maker, an activist, takes into account the complete stochastic implications of the bubble when setting policy. We examine the optimal policy recommendations of these two policy-makers across a range of plausible assumptions about the bubble. We show that the optimal monetary policy recommendations of the activist depend on the detailed stochastic properties of the bubble. There are some circumstances in which the activist clearly recommends tighter policy than that of the sceptic, while in other cases, the appropriate recommendation is to be looser than the sceptic. Other things equal, the case for ‘leaning against’ a bubble with monetary policy is stronger the lower the probability of the bubble bursting of its own accord, the larger the efficiency losses associated with big bubbles, and the higher the assumed impact of monetary policy on the bubble process.optimal monetary policy; asset-price bubble

Single spin-polarised Fermi surface in SrTiO3_3 thin films

The 2D electron gas (2DEG) formed at the surface of SrTiO$_3$(001) has attracted great interest because of its fascinating physical properties and potential as a novel electronic platform, but up to now has eluded a comprehensible way to tune its properties. Using angle-resolved photoemission spectroscopy with and without spin detection we here show that the band filling can be controlled by growing thin SrTiO$_3$ films on Nb doped SrTiO$_3$(001) substrates. This results in a single spin-polarised 2D Fermi surface, which bears potential as platform for Majorana physics. Based on our results it can furthermore be concluded that the 2DEG does not extend more than 2 unit cells into the film and that its properties depend on the amount of SrO$_x$ at the surface and possibly the dielectric response of the system

Observation of Wannier-Stark localization at the surface of BaTiO3_3 films by photoemission

Observation of Bloch oscillations and Wannier-Stark localization of charge carriers is typically impossible in single-crystals, because an electric field higher than the breakdown voltage is required. In BaTiO$_3$ however, high intrinsic electric fields are present due to its ferroelectric properties. With angle-resolved photoemission we directly probe the Wannier-Stark localized surface states of the BaTiO$_3$ film-vacuum interface and show that this effect extends to thin SrTiO$_3$ overlayers. The electrons are found to be localized along the in-plane polarization direction of the BaTiO$_3$ film

How Should Monetary Policy Respond to Asset-Price Bubbles?

We present a simple macroeconomic model that includes a role for an asset-price bubble. We then derive optimal monetary policy settings for two policymakers: a skeptic, for whom the best forecast of future asset prices is the current price; and an activist, whose policy recommendations take into account the complete stochastic implications of the bubble. We show that the activist’s recommendations depend sensitively on the detailed stochastic properties of the bubble. In some circumstances the activist clearly recommends tighter policy than the skeptic, but in others the appropriate recommendation is to be looser. Our results highlight the stringent informational requirements inherent in an activist policy approach to handling asset-price bubbles

Health professional networks as a vector for improving healthcare quality and safety: a systematic review

Background: While there is a considerable corpus of theoretical and empirical literature on networks within and outside of the health sector, multiple research questions are yet to be answered. Objective: To conduct a systematic review of studies of professionals' network structures, identifying factors associated with network effectiveness and sustainability, particularly in relation to quality of care and patient safety. Methods: The authors searched MEDLINE, CINAHL, EMBASE, Web of Science and Business Source Premier from January 1995 to December 2009. Results: A majority of the 26 unique studies identified used social network analysis to examine structural relationships in networks: structural relationships within and between networks, health professionals and their social context, health collaboratives and partnerships, and knowledge sharing networks. Key aspects of networks explored were administrative and clinical exchanges, network performance, integration, stability and influences on the quality of healthcare. More recent studies show that cohesive and collaborative health professional networks can facilitate the coordination of care and contribute to improving quality and safety of care. Structural network vulnerabilities include cliques, professional and gender homophily, and over-reliance on central agencies or individuals. Conclusions: Effective professional networks employ natural structural network features (eg, bridges, brokers, density, centrality, degrees of separation, social capital, trust) in producing collaboratively oriented healthcare. This requires efficient transmission of information and social and professional interaction within and across networks. For those using networks to improve care, recurring success factors are understanding your network's characteristics, attending to its functioning and investing time in facilitating its improvement. Despite this, there is no guarantee that time spent on networks will necessarily improve patient care

Intermediate septal accessory pathways: Electrocardiographic characteristics, electrophysiologic observations and their surgical implications

AbstractIntermediate septal accessory pathways are located in close proximity to the atrioventricular (AV) node and His bundle, have unique features that distinguish them from typical anterior and posterior accessory pathways and have been associated with a high risk for unsuccessful pathway division and the production of complete AV block after surgery. Between July 1986 and May 1990, 4 of 70 patients (3 men and 1 woman; mean age 33 ± 13 years) undergoing surgery for accessory pathway division were found to have an intermediate septal accessory pathway. The presenting arrhythmia was atrial fibrillation with rapid anterograde conduction over the accessory pathway in two patients and recurrent orthodromic reciprocating tachycardia in two patients.In all patients, the delta wave on the electrocardiogram (ECG) was inversed in lead V1, but two patterns of delta wave configuration were observed. In three patients (type 1 intermediate septal accessory pathway), the delta wave was upright in lead II, inverted in lead III and isoelectric in lead aVF; the transition from a negative to an upright delta wave occurred in lead V2. The fourth patient exhibited a different delta wave pattern (type 2 intermediate septal accessory pathway). The delta wave was upright in each of leads II, III and aVF; the transition from a negative to an upright delta wave occurred at lead V3.Intraoperative electrophysiologic study localized the atrial insertion of type 1 pathways to the midpoint of Koch's triangle close to the AV node. In the one patient with a type 1 pathway in which both anterograde and retrograde accessory pathway conduction was present, preoperative catheter mapping demonstrated that earliest retrograde atrial activation occurred near the foramen ovale. Intraoperative mapping during anterograde conduction over the type 1 pathway demonstrated earliest epicardial ventricular activation to occur simultaneously at the crux and the base of the aorta. The atrial insertion of the type 2 intermediate septal accessory pathway was localized to the apex of Koch's triangle in close proximity to the bundle of His. Preoperative catheter mapping revealed that earliest retrograde atrial activation occurred on the His bundle electrogram. Intraoperative mapping during anterograde conduction over the type 2 pathway demonstrated that earliest epicardial ventricular activation occurred anteriorly at the base of the aorta.Intraoperative ablation of the intermediate septal accessory pathway was accomplished by cooling the endocardium at the site of pathway insertion on the atrial side of the tricuspid anulus with a 5 mm cryoprobe. Patients with a type 1 intermediate septal accessory pathway had preservation of AV conduction, but the patient with the type 2 pathway did not and required permanent pacing. At late follow-up study, no patient has had return of intermediate septal accessory pathway conduction. Distinguishing an intermediate septal accessory pathway close to the AV node (type 1) from one close to the His bundle (type 2) is useful to predict both surgical success and success without the production of permanent complete AV block

Are preoperative CT variables associated with the success or failure of subsequent ventral hernia repair: nested case-control study

OBJECTIVES: Systematic review of CT measurements to predict the success or failure of subsequent ventral hernia repair has found limited data available in the indexed literature. To rectify this, we investigated multiple preoperative CT metrics to identify if any were associated with postoperative reherniation. METHODS: Following ethical permission, we identified patients who had undergone ventral hernia repair and had preoperative CT scanning available. Two radiologists made multiple measurements of the hernia and abdominal musculature from these scans, including loss of domain. Patients were divided subsequently into two groups, defined by hernia recurrence at 1-year subsequent to surgery. Hypothesis testing investigated any differences between CT measurements from each group. RESULTS: One hundred eighty-eight patients (95 male) were identified, 34 (18%) whose hernia had recurred by 1-year. Only three of 34 CT measurements were significantly different when patients whose hernia had recurred were compared to those who had not; these significant findings were assumed contingent on multiple testing. In particular, preoperative hernia volume (recurrence 155.3 cc [IQR 355.65] vs. no recurrence 78.2 [IQR 303.52], p = 0.26) nor loss of domain, whether calculated using the Tanaka (recurrence 0.02 [0.04] vs. no recurrence 0.009 [0.04], p = 0.33) or Sabbagh (recurrence 0.019 [0.05] vs. no recurrence 0.009 [0.04], p = 0.25) methods, differed between significantly between groups. CONCLUSIONS: Preoperative CT measurements of ventral hernia morphology, including loss of domain, appear unrelated to postoperative recurrence. It is likely that the importance of such measurements to predict recurrence is outweighed by other patient factors and surgical reconstruction technique. KEY POINTS: • Preoperative CT scanning is often performed for ventral hernia but systematic review revealed little data regarding whether CT variables predict postoperative reherniation. • We found that the large majority of CT measurements, including loss of domain, did not differ significantly between patients whose hernia did and did not recur. • It is likely that the importance of CT measurements to predict recurrence is outweighed by other patient factors and surgical reconstruction technique

Spin-resolved electronic response to the phase transition in MoTe2_2

The semimetal MoTe$_2$ is studied by spin- and angle- resolved photoemission spectroscopy to probe the detailed electronic structure underlying its broad range of response behavior. A novel spin-texture is uncovered in the bulk Fermi surface of the non-centrosymmetric structural phase that is consistent with first-principles calculations. The spin-texture is three-dimensional, both in terms of momentum dependence and spin-orientation, and is not completely suppressed above the centrosymmetry-breaking transition temperature. Two types of surface Fermi arc are found to persist well above the transition temperature. The appearance of a large Fermi arc depends strongly on thermal history, and the electron quasiparticle lifetimes are greatly enhanced in the initial cooling. The results indicate that polar instability with strong electron-lattice interactions exists near the surface when the bulk is largely in a centrosymmetric phase

METRIC-EF: magnetic resonance enterography to predict disabling disease in newly diagnosed Crohn's disease-protocol for a multicentre, non-randomised, single-arm, prospective study

INTRODUCTION: Crohn's disease (CD) is characterised by discontinuous, relapsing enteric inflammation. Instituting advanced therapies at an early stage to suppress inflammation aims to prevent future complications such as stricturing or penetrating disease, and subsequent surgical resection. Therapeutics are effective but associated with certain side-effects and relatively expensive. There is therefore an urgent need for robust methods to predict which newly diagnosed patients will develop disabling disease, to identify patients who are most likely to benefit from early, advanced therapies. We aim to determine if magnetic resonance enterography (MRE) features at diagnosis improve prediction of disabling CD within 5 years of diagnosis. METHODS AND ANALYSIS: We describe the protocol for a multicentre, non-randomised, single-arm, prospective study of adult patients with newly diagnosed CD. We will use patients already recruited to the METRIC study and extend their clinical follow-up, as well as a separate group of newly diagnosed patients who were not part of the METRIC trial (MRE within 3 months of diagnosis), to ensure an adequate sample size. Follow-up will extend for at least 4 years. The primary outcome is to evaluate the comparative predictive ability of prognostic models incorporating MRE severity scores (Magnetic resonance Enterography Global Score (MEGS), simplified MAgnetic Resonance Index of Activity (sMaRIA) and Lémann Index) versus models using standard characteristics alone to predict disabling CD (modified Beaugerie definition) within 5 years of new diagnosis. ETHICS AND DISSEMINATION: This study protocol achieved National Health Service Research Ethics Committee (NHS REC), London-Hampstead Research Ethics Committee approval (IRAS 217422). Our findings will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: ISRCTN76899103