274 research outputs found
Inflation dynamics under optimal discretionary fiscal and monetary policies
We examine the dynamic properties of inflation in a model of optimal discretionary fiscal and monetary policies. The lack of commitment and the presence of nominally risk-free debt provide the government with an incentive to implement policies which induce positive and persistent inflation rates. We show that this property obtains already in an environment with flexible prices and perfectly competitive product markets. Introducing nominal rigidities and imperfect competition has no qualitative but important quantitative implications. In particular, with a modest degree of price stickiness our model generates inflation dynamics very similar to those experienced in the U.S. since the Volcker disinflation of the early 1980s.
Optimal Fiscal and Monetary Policy Without Commitment
This paper studies optimal fiscal and monetary policy in a stochastic economy with imperfectly competitive product markets and a discretionary government. We find that, in the flexible price economy, optimal time-consistent policy implements the Friedman rule independently of the degree of imperfect competition. This result is in contrast to the Ramsey literature, where the Friedman rule emerges as the optimal policy only if markets are perfectly competitive. Second, once nominal rigidities are introduced, the Friedman rule ceases to be optimal, inflation rates are low and stable, and tax rates are relatively volatile. Finally, optimal time-consistent policy under sticky prices does not generate the near-random walk behavior of taxes and real debt that can be observed under optimal policy in the Ramsey problem. A common reason for these results is that the discretionary government, in an effort to asymptotically eliminate its time-consistency problem, accumulates a large net asset position such that it can finance its expenditures via the associated interest earnings.
Central bank independence and the monetary instrument problem
We study the monetary instrument problem in a model of optimal discretionary fiscal and monetary policy. The policy problem is cast as a dynamic game between the central bank, the fiscal authority, and the private sector. We show that, as long as there is a conflict of interest between the two policy-makers, the central bank's monetary instrument choice critically affects the Markov-perfect Nash equilibrium of this game. Focussing on a scenario where the fiscal authority is impatient relative to the monetary authority, we show that the equilibrium allocation is typically characterized by a public spending bias if the central bank uses the nominal money supply as its instrument. If it uses instead the nominal interest rate, the central bank can prevent distortions due to fiscal impatience and implement the same equilibrium allocation that would obtain under cooperation of two benevolent policy authorities. Despite this property, the welfare-maximizing choice of instrument depends on the economic environment under consideration. In particular, the money growth instrument is to be preferred whenever fiscal impatience has positive welfare effects, which is easily possible under lack of commitment.
Is NIRS monitoring well tolerated in term and preterm neonates?
Background. Near infrared spectroscopy (NIRS) is a new, non-invasive monitoring method in neonates, which has now become part of routine monitoring in many neonatal intensive care units (NICU). New, additional, non-invasive technical monitoring might have an influence on neonatal wellbeing.
Objectives. The aim of the present study was to evaluate the wellbeing of neonates during peripheral and cerebral NIRS monitoring and venous occlusions.
Methods. In the present study, secondary outcome parameters of prospective observational studies with NIRS in term and preterm neonates were analysed. Heart rate (HR), arterial oxygen saturation (SpO2), respiratory rate (RR), mean arterial blood pressure (MABP), pain score and skin condition at four defined time points during NIRS measurements of regional tissue oxygenation were recorded and analysed.
Results. Thirty-six term and preterm neonates were included (gestational age (GA) 36±1 week, 2779±930g birth weight). SpO2 and peripheral tissue oxygenation index (pTOI) increased and HR dropped while RR, mean MABP and pain scores remained unchanged during NIRS measurements. In eight infants, a mildly irritated area of skin was noted where the NIRS sensors had been attached.
Conclusion. Cerebral and peripheral NIRS monitoring and venous occlusions were painless and well tolerated by term and preterm neonates
Leukocytes influence peripheral tissue oxygenation and perfusion in neonates
Background. Leukocyte counts may influence peripheral (micro) circulation due to changes in rheology. The aim of this study was to investigate a possible association between leukocyte counts and peripheral tissue oxygenation/perfusion measured with near infrared spectroscopy (NIRS) in term and preterm neonates. Methods. In this observational study we included term and preterm neonates within the first 2 months of life, in whom peripheral tissue NIRS measurements were performed and blood samples (leukocytes and C reactive protein (CRP)) taken to investigate clinical signs of infection. Tissue-oxygenation index (TOI), fractional oxygen extraction (FTEO), oxygen delivery (DO
2 ), oxygen consumption (VO
TOI, FTOE, DO 2
, VO 2
2 ) and vascular resistance (VR) were measured by NIRS and venous occlusion method.
and VR were correlated to leukocyte counts on the same day and maximal CRP levels within 24 hours (CRP max). Results. In 180 infants, with a mean gestational age of 35.5±3.3 weeks, leukocyte counts were 16546± 8830/l (median 14830; range 1790 to 67840) and CRP max was 8.0± 19.0 mg/l (median 0.0; range 0.0 to 110.0mg/l). TOI was 71.1±5.5%, FTOE 28.5±6.1%, DO
2 46.7±19.7, VO
2 12.5±4.4 and VR 11.7±6.4.
Leukocyte counts correlated negatively (r= -0.21; p= 0.005) with TOI and positively (r=0.17; p=0.029) with VR. Correlations with CRP max did not reach significance. Conclusion. We demonstrated that peripheral tissue oxygen consumption decreases and vascular resistance increases with increasing leukocyte counts
Precision and normal values of cerebral blood volume in preterm neonates using time-resolved near-infrared spectroscopy
AIM
To investigate cerebral blood volume (CBV) in preterm neonates using time-resolved near-infrared spectroscopy.
METHODS
In this prospective observational study, time-resolved near-infrared spectroscopy measurements of CBV using tNIRS-1 were performed in 70 preterm neonates. For measurements, a sensor was placed for a duration of 1 min, followed by four further reapplications of the sensor, overall five measurements.
RESULTS
In this study, 70 preterm neonates with a mean ± SD gestational age of 33.4 ± 1.7 weeks and a birthweight of 1931 ± 398 g were included with a postnatal age of 4.7 ± 2.0 days. Altogether, 2383 CBV values were obtained with an overall mean of 1.85 ± 0.30 mL/100 g brain. A total of 95% of the measured CBV values varied in a range from -0.31 to 0.33 from the overall individual mean. Taking the deviation of the mean of each single application for each patient, this range reduced from -0.07 to 0.07. The precision of the measurement defined as within-variation in CBV was 0.24 mL/100 g brain.
CONCLUSION
The overall mean CBV in stable preterm neonates was 1.85 ± 0.30 mL/100 g brain. The within-variation in CBV was 0.24 mL/100 g brain. Based on the precision obtained by our data, CBV of 1.85 ± 0.30 mL/100 g brain may be assumed as normal value for this cohort
Upward Lightning at the Gaisberg Tower: Initiation Mechanism and Flash Type and the Atmospheric Influence
Upward lightning is much rarer than downward lightning and requires tall
(~m) structures to initiate. It may be either triggered by other
lightning discharges or completely self-initiated. While conventional lightning
location systems reliably detect downward lightning, they miss a specific flash
type of upward lightning that consists only of a continuous current. Globally,
only few specially instrumented towers can detect this flash type. The
proliferation of wind turbines in combination with large damage from upward
lightning necessitates an improved understanding under which conditions the
self-initiated and the undetected subtype of upward lightning occur. To find
larger-scale meteorological conditions favorable for self-initiated and
undetectable upward lightning, this study uses a random forest machine learning
model. It combines direct measurements at the specially instrumented tower at
Gaisberg mountain in Austria with explanatory variables from larger-scale
atmospheric reanalysis data (ERA5). Atmospheric variables reliably explain
whether upward lightning is self-initiated by the tower or triggered by other
lightning discharges. The most important variable is the height of the
C isotherm above the tall structure: the closer it is the higher is
the probability of self-initiated upward lightning. Two-meter temperature and
the amount of CAPE are also important. For the occurrence of upward lightning
undetectable by lightning location systems, this study finds a strong
relationship to the absence of lightning in the vicinity
MiR-199a and miR-497 are associated with better overall survival due to increased chemosensitivity in diffuse large b-cell lymphoma patients
Micro-RNAs (miRNAs) are short non-coding single-stranded RNA molecules regulating gene expression at the post-transcriptional level. miRNAs are involved in cell development, differentiation, apoptosis, and proliferation. miRNAs can either function as tumor suppressor genes or oncogenes in various important pathways. The expression of specific miRNAs has been identified to correlate with tumor prognosis. For miRNA expression analysis real-time PCR on 81 samples was performed, including 63 diffuse large B-cell lymphoma (DLBCL, 15 of germinal center B-cell like subtype, 17 non germinal center B-cell, 23 transformed, and eight unclassified) and 18 controls, including nine peripheral B-cells, 5 germinal-center B-cells, four lymphadenitis samples, and 4 lymphoma cell lines (RI-1, SUDHL4, Karpas, U2932). Expression levels of a panel of 11 miRNAs that have been previously involved in other types of cancer (miR-15b_2, miR-16_1*, miR-16_2, miR-16_2*, miR-27a, miR-27a*, miR-98-1, miR-103a, miR-185, miR-199a, and miR-497) were measured and correlated with clinical data. Furthermore, cell lines, lacking miR-199a and miR-497 expression, were electroporated with the two respective miRNAs and treated with standard immunochemotherapy routinely used in patients with DLBCL, followed by functional analyses including cell count and apoptosis assays. Seven miRNAs (miR-16_1*, miR-16_2*, miR-27a, miR-103, miR-185, miR-199, and miR-497) were statistically significantly up-regulated in DLBCL compared to normal germinal cells. However, high expression of miR-497 or miR-199a was associated with better overall survival (p = 0.042 and p = 0.007). Overexpression of miR-199a and miR-497 led to a statistically significant decrease in viable cells in a dose-dependent fashion after exposure to rituximab and various chemotherapeutics relevant in multi-agent lymphoma therapy. Our data indicate that elevated miR-199a and miR-497 levels are associated with improved survival in aggressive lymphoma patients most likely by modifying drug sensitivity to immunochemotherapy. This functional impairment may serve as a potential novel therapeutic target in future treatment of patients with DLBCL
Beyond Infrastructure -- Modelling Scholarly Research and Collaboration
International audienceThis paper explores what is needed to foster an acceptance of digital practices in the humanities beyond the creation of pure infrastructure, specifically in terms of understanding and technically modelling traditional scholarly research within a digital medium while enabling new modes of scholarly work that could only be carried out within a digitally-mediated environment
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