In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Ex Input:
In this paper, we analyze a delayed SEIR epidemic model in which the latent and infected states are infective. The model has a globally asymptotically stable disease-free equilibrium whenever a certain epidemiological threshold, known as the basic reproduction number R 0 , is less than or equal to unity. We investigate the effect of the time delay on the stability of endemic equilibrium when R 0 > 1. We give criteria that ensure that endemic equilibrium is asymptotically stable for all time delays and a Hopf bifurcation occurs as time delay exceeds the critical value. We give formulae for the direction of Hopf bifurcations and the stability of bifurcated periodic solutions by applying the normal form theory and the center manifold reduction for functional differential equations. Numerical simulations are presented to illustrate the analytical results.

Ex Output:
Hopf bifurcation analysis of a delayed SEIR epidemic model with infectious force in latent and infected period

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This study uses panel regression tests to examine the response of hotel performance to international tourism development and crisis events in Taiwan. Hotel performance measures are revenue (revenue per available room and occupancy rate), profitability (return on assets and return on equity) and stock performance. The crises were the earthquake on September 21, 1999 (the 9/21 earthquake), the terrorist attacks of September 11, 2001 in the US (the 9/11 terrorist attacks) and the outbreak of Severe Acute Respiratory Syndrome on April 22, 2003 (the SARS outbreak). This study makes four major contributions. First, test results confirm that international tourism development (ITD), proxied by the growth of total inbound tourist arrivals, has a more direct influence on hotel sales and profitability than it does on hotel stock performance. Second, this study identifies that the absence of a strong tie between ITD and hotel stock returns that was found in previous studies is due to the time-varying discount rate caused by investors' changing expectations for the prospect of future cash flows from holding hotel stocks. Third, this study finds new evidence that while the poor performance of hotel stocks caused by the 9/21 earthquake and the 9/11 terrorist attacks was attributed to the loss of hotel sales revenue, the adverse effect of the SARS outbreak on hotel stock returns is attributed not only to decreased hotel sales revenue but also to the increased discount rate. Lastly, this study is the first to investigate whether the response of hotel stock returns to ITD depends on the state of economy and concludes that the response of hotel stock performance to ITD in business cycle contraction is statistically different from that in business cycle expansion. Further, although the influence of ITD on hotel stock performance is still irrelevant during expansion periods, ITD can significantly enhance hotel stock returns during contraction periods.

Ex Output:
The response of hotel performance to international tourism development and crisis events

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Background: Campylobacter jejuni is commonly found in the gastrointestinal tract of many food-animals including sheep without causing visible clinical symptoms of disease. However, C. jejuni has been implicated in ovine abortion cases worldwide. Specifically, in the USA, the C. jejuni sheep abortion (SA) clone has been increasingly associated with sheep abortion. In vivo studies in sheep (the natural host) are needed to better characterize the virulence potential and pathogenesis of this clone. Results: Pregnant ewes intravenously (IV) or orally inoculated with ovine or bovine abortion-associated C. jejuni SA clones exhibited partial or complete uterine prolapse with retained placenta, and abortion or stillbirth, whereas delivery of healthy lambs occurred in pregnant ewes inoculated with C. jejuni 81-176 or in the uninfected group. In sheep inoculated with the SA clone, histopathological lesions including suppurative necrotizing placentitis and/or endometritis coincided with: 1) increased apoptotic death of trophoblasts, 2) increased expression of the host genes (e.g. genes encoding interleukin IL-6 and IL-15) related to cellular necrosis and pro-inflammatory responses in uterus, and 3) decreased expression of the genes encoding GATA binding protein 6, chordin, and insulin-like 3 (INSL3) that account for embryonic development in uterus. Immunohistochemistry revealed localization of bacterial antigens in trophoblasts lining the chorioallantoic membrane of ewes inoculated with the C. jejuni SA clone. Conclusions: The results showed that C. jejuni SA clones are capable of causing abortion or stillbirth in experimentally infected sheep. Furthermore, down-or up-regulation of specific genes in the uterus of infected pregnant ewes might implicate host genes in facilitating the disease progression. Since the C. jejuni SA strains share genotypic similarities with clones that have been isolated from human clinical cases of gastroenteritis, these strains might represent a potential public health risk.

Ex Output:
Insights into potential pathogenesis mechanisms associated with Campylobacter jejuni-induced abortion in ewes