Przemysław Włodarczyk

The article analyses the influence of crisis-induced changes in economic activity on the monetary transmission mechanism in the small open economies of Czechia, Hungary, Poland, and Sweden from 2000: 1 to 2016: 5 using the Markov Switching Structural Bayesian Vector Autoregressive models. The results confirm that in countries where the exchange rate transmission channel is relatively weak (Hungary and Sweden), changes in volatilities coincide with changes in the coefficients of the monetary transmission mechanism, reducing the efficiency of a monetary policy during a crisis. The changes of the coefficients occurred in neither Poland nor Czechia, where the exchange rate pass-through was not closed completely. The results imply that in small open economies, public authorities’ efforts to sustain exchange rate pass-through may critically affect their ability to retain monetary control during a crisis.

Introduction: There are still no effective diagnostic and prognostic biomarkers in pancreatic ductal adenocarcinoma (PDAC). The differentiation between PDAC and chronic pancreatitis (CP) is often challenging. The inflammatory mass in the course of CP causes diagnostic difficulties in differentiating them from neoplastic lesions and, thus, delays the initiation of radical treatment. Insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 2 (IGFBP-2) form a network involved in PDAC development. The role of IGFs in promoting pancreatic cancer cell proliferation, survival, and migration is well established, and their ability to stimulate tumor growth and metastasis is well documented. The aim of the study was to evaluate the usability of IGF-1, IGFBP-2, and IGF-1/IGFBP-2 ratio in PDAC and CP differentiation. Material and methods: The study included 137 patients: 89 patients with PDAC and 48 patients with CP. All subjects were tested for the levels of IGF-1 and IGFBP-2 using the ELISA method (Corgenix UK Ltd. R&D Systems), along with the level of CA 19-9 in serum. Additionally, the IGF-1/IGFBP-2 ratio was calculated. Further analyses used logit and probit models with varying determinants in order to discern between PDAC and CP patients. The models served as a basis for AUROC calculation. Results: The mean IGF-1 serum level was equal to 52.12 ± 33.13 ng/mL in PDAC vs. 74.23 ± 48.98 ng/mL in CP (p = 0.0053). The mean level of IGFBP-2 was equal to 305.95 ± 194.58 ng/mL in PDAC vs. 485.43 ± 299 ng/mL in CP (p = 0.0002). The mean CA 19-9 serum concentration was 434.95 ± 419.98 U/mL in PDAC vs. 78.07 ± 182.36 U/mL in CP (p = 0.0000). The mean IGF-1/IGFBP-2 ratio was 0.213 ± 0.14 in PDAC vs. 0.277 ± 0.33 in CP (p = 0.1914). The diagnostic usefulness of indicators for the purpose of PDAC and CP differentiation was assessed by means of AUROC comparison. The AUROCs of IGF-1, IGFBP-2, and IGF-1/IGFBP-2 ratio ranged below 0.7, being lower than the AUROC of CA 19-9 (0.7953; 0.719 within 95% CI). Together, the CA 19-9 and IGFBP-2 AUROCs also ranged below 0.8. When age was included, the AUROC increased to 0.8632, and its 95% confidence interval held above the 0.8 limit. The sensitivity of the used markers was not correlated to the stage of pancreatic PDAC. Conclusions: The presented results indicate that CA 19-9 is a marker demonstrating high potential for PDAC and CP differentiation. The inclusion of additional variables into the model, such as the serum level of IGF-1 or IGFBP-2, slightly increased the sensitivity in differentiating CP from PDAC. The IGF-1/IGFBP-2 ratio turned out to be a good marker of pancreatic diseases, but insufficient for the purpose of CP and PDAC differentiation.

The COVID-19 pandemic has raised many questions on how to manage an epidemiological and economic crisis around the world. Since the beginning of the COVID-19 pandemic, scientists and policy makers have been asking how effective lockdowns are in preventing and controlling the spread of the virus. In the absence of vaccines, the regulators lacked any plausible alternatives. Nevertheless, after the introduction of vaccinations, to what extent the conclusions of these analyses are still valid should be considered. In this paper, we present a study on the effect of vaccinations within the dynamic stochastic general equilibrium model with an agent-based epidemic component. Thus, we validated the results regarding the need to use lockdowns as an efficient tool for preventing and controlling epidemics that were obtained in November 2020.

Introduction: Insulin-like growth factor 1 (IGF-1) has been connected with development of pancreatic ductal adenocarcinoma (PDAC). Aim: To evaluate the serum concentration levels of IGF-1 and insulin-like growth factor binding protein 2 (IGFBP-2) in patients with chronic pancreatitis (CP) and PDAC. Their values in diabetes mellitus (DM) were also assessed. Material and methods: The study included 83 patients with CP 92 patients with PDAC, and 20 subjects as a control group. The concentrations of IGF-1 and IGFBP-2 were estimated with ELISA (Corgenix UK Ltd, R&D Systems). Results: The IGF-1 was higher in CP compared with PDAC (81.11 +/- 57.18 ng/ml vs. 53.18 +/- 36.05 ng/ml, p < 0.001), and both CP and PDAC were different from controls (81.11 +/- 57.18 ng/ml vs. 70.66 +/- 16.57 ng/ml, p < 0.001 and 53.18 +/- 36.05 ng/ml vs. 70.66 +/- 16.57 ng/ml, p < 0.001). CP without cysts have lower IGF-1 compared to those with CP and cysts (60.35 +/- 34.68 ng/ml vs. 93.55 +/- 64.78 ng/ml, p < 0.05). IGF-1 in CP without DM was higher compared to IGF-1 in PDAC without DM (91.13 +/- 65.48 ng/ml vs. 54.75 +/- 40.41 ng/ml, p < 0.001). In CP and DM the IGF-1 was elevated in comparison to PDAC and DM (62.20 +/- 32.38 ng/ml vs. 48.45 +/- 24.88 ng/ml, p < 0.05). IGFBP-2 was higher in CP compared to PDAC (512.42 +/- 299.77 ng/ml vs 301.59 +/- 190.36 ng/ml, p < 0.001). In CP and PDAC the IGFBP-2 level was elevated compared to the control group (512.42 +/- 299.77 ng/ml vs. 51.92 +/- 29.40 ng/ml, p < 0.001 and 301.59 +/- 190.36 ng/ml vs. 51.92 +/- 29.40 ng/ml, p < 0.001). IGFBP-2 in CP without DM was higher compared to PDAC without DM (559.39 +/- 281.43 vs. 296.53 +/- 196.93, p < 0.001). Conclusions: IGF-1 and IGFBP-2 may be biomarkers of CP and PDAC. IGF-1 may be an indicator that signals whether pancreatic diabetes is from CP or PDAC.

The ongoing COVID-19 pandemic has raised numerous questions concerning the shape and range of state interventions the goals of which are to reduce the number of infections and deaths. The lockdowns, which have become the most popular response worldwide, are assessed as being an outdated and economically inefficient way to fight the disease. However, in the absence of efficient cures and vaccines, there is a lack of viable alternatives. In this paper we assess the economic consequences of the epidemic prevention and control schemes that were introduced in order to respond to the COVID-19 pandemic. The analyses report the results of epidemic simulations that were obtained using the agent-based modelling methods under the different response schemes and their use in order to provide conditional forecasts of the standard economic variables. The forecasts were obtained using the dynamic stochastic general equilibrium model (DSGE) with the labour market component.

Background: Insulin-like growth factor 1 (IGF-1) and insulin-like growth factor–binding protein 2 (IGFBP-2) are proteins that belong to the IGF axis, which is involved in glucose and lipid metabolism and may as well promote carcinogenesis. Goals: The aim of this study was to evaluate the serum concentration levels of IGF-1 and IGFBP-2 in patients with newly diagnosed pancreatic adenocarcinoma (PDAC) to verify their possible role in the diagnosis of the disease. Study: The study included 69 patients with PDAC and 20 healthy controls. The concentrations of IGF-1 and IGFBP-2 were estimated by means of ELISA. The study protocol was approved by the Bioethics Committee at the Medical University of Lodz in Poland. Results: PDAC patients compared with controls have a significantly lower mean serum IGF-1 level (45.83±30.03 vs. 70.66±60.57 ng/mL; PP<0.0001). The results show that, at the 0.01 sensitivity level, the IGF-1/IGFBP-2 ratio <0.85 points indicates PDAC presence. At this level of sensitivity, the test has a specificity of 0.097 (α=0.01; β=0.097; IGF-1/IGFBP-2≤0.85). Conclusions: Our results show that IGF-1 to IGFBP-2 ratio ≤0.85 may be a powerful PDAC indicator. Further studies in this area in a larger patient group are necessary to confirm our findings.

The aim of this article is to review a body of research that uses labour market components to build models of Dynamic Stochastic General Equilibrium (DSGE) and to assess the implications of such models for monetary policy. The article presents methods that might be used to account for...

The stability of the transmitted optical frequency in a single bidirectionally operated fiber was compared with stability in a link consisting of two separate unidirectional fibers. The measurements were performed in a standard closed-loop system canceling the fiber induced phase noise. It was found that phase fluctuations in the higher frequency band (acoustic noise) are well suppressed in both configurations (single bidirectional fiber and separate unidirectional fibers). The long-term drifts however are not fully compensated in a link consisting of two separate unidirectional fibers, but still about two orders of magnitude noise reduction was observed in comparison with not compensated transfer.