Mean reversion of inflation rates in 19 OECD countries: Evidence from panel Lm unit root tests with structural breaks

The paper applies the recently developed panel LM unit root tests with heterogeneous structural breaks by Im et al., [The Oxford Bulletin of Economics and Statistics, 2005] in order to re-examine the validity of mean reversion in the inflation rates of 19 OECD countries for the time period 1960-2004. Our empirical findings are favorable to the stationarity of the inflation ratesand therefore point to the absence of hyperinflation in the majority of the countries. The results indicate that most shocks to inflation rates are temporary and soon converge when we control for breaks, with the inflation rates showing mean reversion. Overall, some policy implications are obtained in this paper.Inflation

Are Fruit and Vegetable Prices Non-linear Stationary? Evidence from Smooth Transition Autoregressive Models

Over the last decade, there has been a growing interest in investigating agricultural commodity prices. We apply two more powerful smooth transition autoregressive models of the non-linear unit-root test - namely, the ESTAR model of Kapetanios et al. [Journal of Econometrics (2003)] and the LSTAR model of Leybourne, et a . [Journal of Time Series Analysis (1998)] - with a view to investigating non-linear stationarity for the retail prices of 8 major kinds of fruit and 18 major kinds of vegetable in Taiwan. The empirical evidence clearly finds that the Kapetanios et al. model provides solid, substantive evidence in favor of a non-linear mean-reverting adjustment for the individual price of 4 kinds of fruit and 5 kinds of vegetable. However, when we employ the Leybourne et al. model, we find that any such similar evidence of non-linear stationarity is considerably weaker. Finally, compared with the traditional linear unit root tests, it is important to note here that, all in all, the non-linear unit root tests do indeed provide much more evidence of the stationarity, albeit to varying degrees. This paper offers some policy implications.Smooth transition autoregressive model; Non-linear stationary; Fruit price; Vegetable price; Taiwan

The protective role of carotenoids and polyphenols in patients with head and neck cancer

AbstractHead and neck cancer is a critical global health problem and approximately 650,000 patients per year are diagnosed with this type of cancer. In addition, head and neck cancer exhibits a high recurrence rate, readily causing second primary cancers in other locations, often yielding a poor prognosis. Current medical and surgical treatment options result in considerable impairment of speaking and swallowing functions, with side effects such as nausea, vomiting, bone marrow suppression, and renal damage, thereby impairing patients' quality of life. Thus, developing a prevention and therapeutic intervention strategy for head and neck cancer is vital. Phytochemicals have been shown to have a unique ability to protect cells from damage and modulation of cell repair. The chemopreventive activities of phytochemicals have also been demonstrated to be associated with their antioxidant properties and the induction and stimulation of intercellular communication via gap junctions, which play a role in the regulation of cancer cell cycle, differentiation, apoptosis, and stagnate cancer cell growth. Phytochemicals can also regulate cancer cell signaling pathways, reduce the invasion and metastasis of cancer cells, and protect normal cells during treatment, thus reducing the damage caused by chemotherapy and radiotherapy. The most studied of the chemopreventive effects of phytochemicals are the carotenoids and phenolics. In this review, we investigated the multiple mechanisms of carotenoids and polyphenols (PPs) for use in preventing head and neck cancer, reducing the side effects of chemotherapy and radiotherapy, improving patient survival rates, and reducing the occurrence rate of second primary cancers

Gender and Posture are Significant Risk Factors to Musculoskeletal Symptoms during Touchscreen Tablet Computer Use

[Purpose] To investigate the prevalence of neck and shoulder symptoms during the use of tablet computer, and to identify the risk factors associated with these symptoms. [Subjects and Methods] A cross-sectional survey was conducted to study tablet computer usage, posture during use, and neck and shoulder symptoms in 412 participants in a school setting. Significant risk factors for musculoskeletal symptoms during tablet computer use were identified. [Results] Overall prevalence of musculoskeletal symptoms during tablet computer use was 67.9% with greater prevalence of neck symptoms (neck: 84.6%; shoulder/upper extremity: 65.4%). Significant risk factors associated with symptoms during use were: current musculoskeletal symptoms, gender, roles, and postural factors including: sitting without back support, sitting with device in lap, and lying on the side and on the back during tablet computer use. A multivariate analysis further showed that the odds for females to have symptoms were 2.059 times higher than males. [Conclusion] The findings revealed that female gender and other postural factors were significantly associated with musculoskeletal symptoms during the use of tablet computer. Among all postural factors, sitting without back support was identified as the most important risk factor for having musculoskeletal symptom

Turbine-Compound Free-Piston Linear Alternator Engine.

The free-piston engine (FPE) was being used on stationary power plants and automobile test back in 1950’s. The advantages of the FPE are obtained mainly from the freely moving piston, with which a variable compression ratio can be easily achieved. This gives the possibility of high compression ratio with high efficiency and the flexibility of burning different fuels. With many alternative fuels, such as biofuels under development to replace the traditional gasoline or diesel fuel, the potential of the FPE is again becoming valuable. The primary goal of the present research is to develop a numerical model of the FPE that can be used to understand the conceptual design and operation. Until now, a model for the FPE was not available, so a model is built in Matlab/Simulink with many user-defined functions and algorithms. The second goal was to integrate the FPE with a linear alternator. Historically, the FPE extracted power solely through a power turbine. Many research groups have used the linear alternator with the FPE and have claimed high efficiency. This study focused on using both power extraction devices together, namely turbine-compound free-piston linear alternator (TCFPLA) engine. It is believed that the linear alternator as the secondary power output has the potential to increase the efficiency when combined with the turbine. The most special characteristic of the TCFPLA engine is its energy-recovering configuration. With the air box fully surrounding the combustion chamber, it absorbs most of the heat from the combustion chamber. This heat recovery process was proven in the study to be a great advantage on efficiency. Two important control parameters were defined, namely the bounce chamber mass and the injection position. These two parameters have to change with load for the best performance output. A 2D engine map is generated for various linear alternator output at each given fueling rate. The brake efficiency reached 50% at the mid to high load conditions with high alternator output. This makes the TCFPLA engine very competitive with the diesel engine.PHDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/107140/1/brandlee_1.pd

Patellar Tendon Morphology in Trans-tibial Amputees Utilizing a Prosthesis with a Patellar-tendon- Bearing Feature

A patellar-tendon-bearing (PTB) bar is a common design feature used in the socket of trans-tibial prostheses to place load on the pressure-tolerant tissue. As the patellar tendon in the residual limb is subjected to the perpendicular compressive force not commonly experienced in normal tendons, it is possible for tendon degeneration to occur over time. The purpose of this study was to compare patellar tendon morphology and neovascularity between the residual and intact limbs in trans-tibial amputees and healthy controls. Fifteen unilateral trans-tibial amputees who utilized a prosthesis with a PTB feature and 15 age- and sex- matched controls participated. Sonography was performed at the proximal, mid-, and distal portions of each patellar tendon. One-way ANOVAs were conducted to compare thickness and collagen fber organization and a chi-square analysis was used to compare the presence of neovascularity between the three tendon groups. Compared to healthy controls, both tendons in the amputees exhibited increased thickness at the mid- and distal portions and a higher degree of collagen fber disorganization. Furthermore, neovascularity was more common in the tendon of the residual limb. Our results suggest that the use of a prosthesis with a PTB feature contributes to morphological changes in bilateral patellar tendons

Role of tissue transglutaminase 2 in the acquisition of a mesenchymal-like phenotype in highly invasive A431 tumor cells

<p>Abstract</p> <p>Background</p> <p>Cancer progression is closely linked to the epithelial-mesenchymal transition (EMT) process. Studies have shown that there is increased expression of tissue tranglutaminase (TG2) in advanced invasive cancer cells. TG2 catalyzes the covalent cross-linking of proteins, exhibits G protein activity, and has been implicated in the modulation of cell adhesion, migration, invasion and cancer metastasis. This study explores the molecular mechanisms associated with TG2's involvement in the acquisition of the mesenchymal phenotype using the highly invasive A431-III subline and its parental A431-P cells.</p> <p>Results</p> <p>The A431-III tumor subline displays increased expression of TG2. This is accompanied by enhanced expression of the mesenchymal phenotype, and this expression is reversed by knockdown of endogenous TG2. Consistent with this, overexpression of TG2 in A431-P cells advanced the EMT process. Furthermore, TG2 induced the PI3K/Akt activation and GSK3β inactivation in A431 tumor cells and this increased Snail and MMP-9 expression resulting in higher cell motility. TG2 also upregulated NF-κB activity, which also enhanced Snail and MMP-9 expression resulting in greater cell motility; interestingly, this was associated with the formation of a TG2/NF-κB complex. TG2 facilitated acquisition of a mesenchymal phenotype, which was reversed by inhibitors of PI3K, GSK3 and NF-κB.</p> <p>Conclusions</p> <p>This study reveals that TG2 acts, at least in part, through activation of the PI3K/Akt and NF-κB signaling systems, which then induce the key mediators Snail and MMP-9 that facilitate the attainment of a mesenchymal phenotype. These findings support the possibility that TG2 is a promising target for cancer therapy.</p