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Regime shifts in different economic time series may be interconnected in various ways, some of which are investigated within a Markov-switching modeling framework. We derive restrictions implied by the lead-lag relationship and the conditional independence, estimate the restricted models, and test these dynamic relationships by using the standard likelihood ratio test. Our empirical examples suggest that the stock volatility regime leads the business cycle regime and that the evidence for a cross-border volatility spillover effect is sensitive to model assumptions.

Background: Cigarette smoking increases the risk of diabetes. The gut microbiota plays a crucial role in the pathogenesis of diabetes. However, the overall effects that active smoking has on the digestive tract microbiome are unclear. Smoking-induced alterations in the digestive tract microbiome and hyperglycemia have not been investigated simultaneously. Methods: We develop a rat model of active smoking and comprehensively characterize the effects of active smoking on the microbiota within multiple regions along the digestive tract. Blood glucose and some metabolic factors levels, the microbial diversity and composition, bacterial network correlations and predictive functional profiles were compared between the control group and active smoking group. Findings: We found that active smoking induced hyperglycemia and dramatic reductions in serum insulin and leptin levels. Active smoking did not remarkably alter the alpha diversity in each region, but induced significant difference in the beta diversity and community structure in the gastrointestinal tract. Our results demonstrated that active smoking resulted in a reduced abundance of some butyrate-producing bacteria (i.e. Clostridium) and increased abundance of sulphate-reducing bacteria (i.e. Desulfovibrio and Bilophila) in the stomach and cecum, and enrichment of opportunistic pathogens (i.e. Staphylococcus) in the oral cavity, cecum and colon. Functional prediction suggested that nutritional metabolism function could be impaired and antioxidant activity may be triggered. Interpretation: These results suggest that investigations of the digestive tract microbiome might be useful for further pathogenesis exploration and treatment improvement of smoking-related diseases. Funding Statement: This work was supported by the National Natural Scientific Foundation of China (81870767 & 81570978), the Key Project of Science and Technology Department of Jiangsu Province (BL2014018), the Project of Jiangsu Provincial Medical Youth Talent (QNRC2016118), the Natural Science Foundation of Jiangsu Province (BK20190134), the Preventive Medicine Project of Jiangsu Province (Y2015004), and the Nanjing Medical Science and Technique Development Foundation (ZKX17033 & YKK16162). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: All experimental procedures were approved by the local Animal Care and Ethics Committee [IRB Approval Number: 2015NL-001 (ks)].

Background: The roles of neuropeptides agouti-related peptide (AgRP) and neuropeptide Y (NPY) in feeding behavior regulation have been extensively studied in rodents. However, the biological functions of these peptides in primates are not fully addressed. Methods: Lenti-virus mediated expression of human NPY (hNPY) or human AgRP (hAgRP) in paraventricular nucleus (PVN) of the hypothalamus to establish obesity model in monkeys. Findings: The feeding behavior and bodyweight were significantly increased in transgenic Rhesus Macaques. Whereas, the blood level of glucose and insulin, as well as metabolic parameters, including blood levels of triglyceride (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c), non-esterified free fatty acids (NEFA) and leptin remained unchanged after virus injection. Interpretation: These results have recapitulated some parts of previous reports in rodents, and suggest that these non-germline genetically modified monkeys may provide new models for studying feeding behaviors and related disease, such as obesity and diabetes. Funding Statement: This study was supported by the National Natural Science Foundation of China (81671516 to X. Huang) and National Key R&D Program of China (2016YFC0905901 to X. Huang). Xingxu Huang is sponsored by Startup Foundation of ShanghaiTech University. Declaration of Interests: All authors have no competing interests to declare, financial or otherwise. Ethics Approval Statement: The use and care of animals complied with the guideline of the biomedical research ethics committee at the Shanghai University of Traditional Chinese Medicine. The experimental procedures were approved by the Sichuan Hengshu Bio-Tech Co., Ltd animal care and use committee.

The role of neuropeptides agouti-related peptide (AgRP) and neuropeptide Y (NPY) in feeding behavior regulation have been extensively studied in rodents. However, the biological functions of these peptides in primates are not fully addressed. Here we shown that, through Lenti-virus mediated selective expression of human NPY (hNPY) or human AgRP (hAgRP) in the paraventricular nucleus (PVN), the bodyweight was significantly increased in young Rhesus Macaques. Whereas, the blood level of glucose and insulin, as well as metabolic parameters, including blood level of triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), non-esterified free fatty acids (NEFA) and leptin remain unchanged after virus injection. Although further investigations of long-term effects are needed, these results have recapitulated some parts of previous reports in rodents, and suggest that these non-germlines geneticlly modified monkeys may provide new models for studying feeding behaviors and related disease, such as obesity and diabetes.

We offer improved dating of U.S. business cycle turning points both retrospectively and in real time. This improvement is made possible by augmenting existing Markov-switching dynamic factor models with additional information on stock return volatility. The model significantly improves prediction of the state of the economy using fully revised data. Real-time identification can be made noticeably earlier than NBER announcements, beating both peak and trough announcements for recent recessions by several months.

Recessions and subsequent recoveries are frequently classified as “L-shaped” or “U-shaped,” with output losses in the former being permanent and losses in the latter at least partially made up by higher than average growth during the recovery. We estimate the probability of a U-shaped recovery for post-War NBER recessions. Most earlier recessions were U-shaped but more recent recessions have been L-shaped. The shape of recoveries is tracked relatively well by durable consumption, investment, and labor hours, with shapes suggested by nondurable consumption and employment being less well identified. Perhaps surprisingly, total factor productivity appears to recover rapidly after all recessions.

Ever since the end of the Great Recession, the US economy has experienced a period of mild inflation, which contradicts with the output–inflation relationship depicted by a traditional Phillips curve. This paper examines how the permanent output loss during the Great Recession has affected the ability of the Phillips curve to explain US inflation dynamics. We find great similarity among several established trend–cycle decomposition methods: potential output declined substantially after the Great Recession. Due to the fact that a lower level of potential output implies a lesser deflationary pressure, we then show that the Phillips curve does predict a period of mild inflation. This finding is largely consistent with the observed data.

This paper investigates to what extent the declines of the U.S. real GDP are permanent during the Great Recession. Our trend-cycle decomposition indicates that the Great Recession is associated with a substantial permanent loss in the real GDP manifested in decelerated mean growth rate and lowered trend level. However, the cyclical component played a relatively minor role comparing to other post-war recessions. If the potential output grew at its pre-crisis rate, it could have been 4.5% higher at the end of the Great Recession.

This paper introduces a Bayesian MCMC method, referred to as marginalized mixture sampler, for the state space model whose disturbances follow stochastic volatility processes. The marginalized mixture sampler is based on a mixture-normal approximation of the log-chi square distribution but implemented without the need to simulate the mixture indicator variable. The key innovation is to use the filtering scheme developed by Kim (1994) and the forward-filtering backward-sampling algorithm to generate a proposal series of the latent stochastic volatility process. The proposal series is then accepted according to the Metropolis-Hastings acceptance probability. The new sampler is examined within a unobserved component model used extensively in empirical macroeconomic studies, and it reduces the correlations between MCMC draws substantially comparing to the conventional method. Finally, I applied the new sampler to a model of the real GDP growth rate of the U.S. economy and find the evidence for the time-varying shape of U.S. recessions.

Through the lens of the Taylor rule, New Keynesian models suggest that a central bank can enhance the macroeconomic stability by aiming for a low inflation target and by strengthening the response to changes in inflation, but these two strategies are difficult to be identified empirically.Using the Bayesian model comparison, I find that the evidence for the Markov-switching response to inflation vanishes when the time variations of the inflation target in the past four decades are taken account for. This paper provides empirical supports for the hypothesis that the low-inflation-target policy conducted by Volcker stabilized inflation expectation and contributed to the Great Moderation.