bluuebunny/crossref_metadata_2025 huggingface dataset:
Pricing in the Primary Market for Cat Bonds: New Empirical Evidence
Authors: Braun Alexander
Published: February 2015

We present empirical evidence from the primary market for cat bonds, which provides new insights concerning the prevailing pricing practice of these instruments. For this purpose, transactional information from a multitude of sources has been collected and cross‐checked in order to compile a data set comprising virtually all cat bond tranches that were launched between June 1997 and December 2012. In order to identify the main determinants of the cat bond spread at issuance, a series of OLS regressions with heteroskedasticity‐ and autocorrelation‐consistent standard errors is run. Our results confirm the expected loss as the most important factor. Apart from that, covered territory, sponsor, reinsurance cycle, and the spreads on comparably rated corporate bonds exhibit a major impact. Based on these findings, we then propose an econometric cat bond pricing model that is applicable for all territories, perils, and trigger types. It exhibits a robust fit across different calibration subsamples and achieves a higher in‐sample and out‐of‐sample accuracy than several competing specifications that have been introduced in earlier work.
Portfolio Choice in Retirement—What is The Optimal Home Equity Release Product?
Authors: Hanewald Katja , Post Thomas , Sherris Michael
Published: February 2015

We study the decision problem of the optimal choice between home equity release products from a retired homeowner's perspective in the presence of longevity, long‐term care, house price, and interest rate risk. The individual can choose to release home equity using reverse mortgages or home reversion plans, to buy annuities, and long‐term care insurance. The individual enjoys utility gains from having access to either one of the two equity release products. Higher utility gains are found for the reverse mortgage, as its product features allow for higher lump‐sum payouts and provide downside protection for house prices.
Net Contribution, Liquidity, and Optimal Pension Management
Authors: Choi Changhui , Jang Bong‐Gyu , Kim Changki , Roh Sang‐youn
Published: February 2015

This article presents an optimal portfolio balancing strategy for a pension fund manager in the presence of fixed and proportional transaction costs with respect to stock trades and changes in net contribution. An analytic solution to the one‐period problem is presented and a heuristic method for a multiperiod problem is developed. For reasonably calibrated parameters, we find that our numerical results explain the actual asset allocation schemes of some internationally renowned pension funds. Moreover, we show that net contribution and liquidity have significant impacts on the optimal asset allocation of a pension fund.
THE URBAN–RURAL GAP IN UNIVERSITY ATTENDANCE: DETERMINANTS OF UNIVERSITY PARTICIPATION AMONG CANADIAN YOUTH
Authors: Newbold K. Bruce , Brown W. Mark
Published: February 2015

Based on existing work, there are clear differences in the incidence of degree holders across the urban–rural hierarchy in favor of large urban areas. In large part, this gradient can be traced to the higher probability of obtaining a degree among residents of larger urban centers. Utilizing data from the Youth in Transition Survey (YITS), this paper explores factors that may account for university participation among Canadian youth. It asks whether this difference is due to local access to universities, family characteristics (e.g., parental income, education, and immigrant status), and local labor market characteristics that may increase the incentive for urban youth to attend university.
Improving T cell-induced response to subunit vaccines: opportunities for a proteomic systems approach
Authors: Dunston Christopher R , Herbert Rebecca , Griffiths Helen R
Published: February 2015

Prophylactic vaccines are an effective strategy to prevent development of many infectious diseases. With new and re-emerging infections posing increasing risks to food stocks and the health of the population in general, there is a need to improve the rationale of vaccine development. One key challenge lies in development of an effective T cell-induced response to subunit vaccines at specific sites and in different populations.

Objectives

In this review, we consider how a proteomic systems-based approach can be used to identify putative novel vaccine targets, may be adopted to characterise subunit vaccines and adjuvants fully.

Key findings

Despite the extensive potential for proteomics to aid our understanding of subunit vaccine nature, little work has been reported on identifying MHC 1-binding peptides for subunit vaccines generating T cell responses in the literature to date.

In combination with predictive and structural biology approaches to mapping antigen presentation, proteomics offers a powerful and as yet un-tapped addition to the armoury of vaccine discovery to predict T-cell subset responses and improve vaccine design strategies.
Non‐parametric methods reveal non‐linear functional trait variation of lichens along environmental and fire age gradients
Authors: Nelson Peter R. , McCune Bruce , Roland Carl , Stehn Sarah
Published: February 2015

Questions

Popular methods to analyse community–trait–environment relationships constrain community patterns by trait and environment relationships. What if some traits are strongly associated with community composition but unrelated to environmental variables and vice versa? We take a different approach, unconstrained by this assumption using non‐parametric methods. We applied this technique to lichen (fungal/algal and/or cyanobacterial symbioses) communities across environmental and fire age gradients by measuring richness and cover of four important functional traits: energy generation (type of photosynthetic symbiont), water relations (inferred from growth form), dispersal capability (from vegetative propagules) and microsite specificity (measured by substrate affinity).

Location

Denali National Park and Preserve, Alaska, USA.

Methods

We ordinated plots in species space and regressed trait and environmental variables against ordination axes, resulting in one‐ or two‐dimensional trait and environment surfaces. We then superimposed these surfaces on the ordination to create a new visual display, the ‘hilltop plot’, which enabled simultaneous measurement and display of one‐ and two‐dimensional, non‐linear community–trait–environment associations.

Results

Most traits examined show non‐linear relationships with community structure. Fire favoured simple cladoniiform lichens, species with higher vegetative dispersal capacity and specificity to grow on wood, but excluded the ‘reindeer’ lichens, which had lower cover even more than 20 yrs after fire. Forests had more sorediate lichens than non‐forested habitats, whereas high elevation, rocky areas had more green algal and fruticose lichens. Cyanobacterial lichen richness was positively related to shrub cover, while tripartite (cyanobacteria and green algae in a single lichen) and foliose lichen richness was highest in areas with higher moss cover.

Conclusions

Different combinations of lichen functional traits peaked along environmental and disturbance gradients, which we interpreted as balancing energy generation, water relations, vegetative dispersal and habitat specificity. Our method of trait–environment–community analysis revealed numerous one‐ and two‐dimensional, non‐linear relationships between community composition and functional traits, environmental variables and fire age gradients, which informed mechanisms behind community assembly. Our results indicate non‐parametric and non‐linear methods of trait–environment–community analysis have the potential to detect patterns that would have been missed using current popular techniques.
Prevalence and risk factors for biopsy‐proven non‐alcoholic fatty liver disease and non‐alcoholic steatohepatitis in a prospective cohort of adult patients with gallstones
Authors: García‐Monzón Carmelo , Vargas‐Castrillón Javier , Porrero José Luís , Alonso María Teresa , Bonachía Oscar , Castillo María José , Marcos Alberto , Quirós Esther , Ramos Beatriz , Sánchez‐Cabezudo Carlos , Villar Sol , Sáez Alicia , Rodríguez de Cía Javier , del Pozo Elvira , Vega‐Piris Lorena , Soto‐Fernández Susana , Lo Iacono Oreste , Miquilena‐Colina María Eugenia
Published: February 2015

Background & Aims

Relationship between gallstones and non‐alcoholic fatty liver disease (NAFLD), and largely non‐alcoholic steatohepatitis (NASH), is uncertain.

Aim

To determine the prevalence, non‐invasive fibrosis markers profile and risk factors for biopsy‐proven NAFLD and NASH among patients with gallstones.

Methods

Anthropometric and laboratory evaluation, an abdominal ultrasound and a liver biopsy were performed to 215 consecutive patients with gallstones referred for cholecystectomy.

Results

Prevalence of NASH was 10.2% whereas that of simple steatosis (SS) was 41.4%. In the cohort of NAFLD patients, negative predictive values for advanced fibrosis of FIB‐4 and NAFLD fibrosis score were 96 and 95% respectively. Gallstone patients with NASH had a higher mean homeostatic model assessment (HOMA) score than those with SS (P = 0.015). Noteworthy, NASH was 2.5‐fold more frequent in patients with gallstones who had metabolic syndrome than in those who did not (P < 0.001). Fatty liver on ultrasound was observed in 90.9% of gallstone patients with NASH compared with 61.8% of those with SS (P = 0.044). Using multivariate logistic regression, increased HOMA score (OR, 3.47; 95% CI, 1.41–8.52; P = 0.007) and fatty liver on ultrasound (OR, 23.27; 95% CI, 4.15–130.55; P < 0.001) were the only factors independently associated with NASH.

Conclusions

Prevalence of NASH among patients with gallstones is lower than estimated previously, but NASH is frequent particularly in those patients with concurrent metabolic syndrome. The combination of an increased HOMA score with fatty liver on ultrasound has a good accuracy for predicting NASH in patients with gallstones.
The APSES transcription factor LmStuA is required for sporulation, pathogenic development and effector gene expression in Leptosphaeria maculans
Authors: Soyer Jessica L. , Hamiot Audrey , Ollivier Bénédicte , Balesdent Marie‐Hélène , Rouxel Thierry , Fudal Isabelle
Published: February 2015

Leptosphaeria maculans causes stem canker of oilseed rape (Brassica napus). The APSES transcription factor StuA is a key developmental regulator of fungi, involved in morphogenesis, conidia production and also more recently described as required for secondary metabolite production and for effector gene expression in phytopathogenic fungi. We investigated the involvement of the orthologue of StuA in L. maculans, LmStuA, in morphogenesis, pathogenicity and effector gene expression. LmStuA is induced during mycelial growth and at 14 days after infection, corresponding to the development of pycnidia on oilseed rape leaves, consistent with the function of StuA described so far. We set up the functional characterization of LmStuA using an RNA interference approach. Silenced LmStuA transformants showed typical phenotypic defects of StuA mutants with altered growth in axenic culture and impaired conidia production and perithecia formation. Silencing of LmStuA abolished the pathogenicity of L. maculans on oilseed rape leaves and also resulted in a drastic decrease in expression of at least three effector genes during in planta infection, suggesting either that LmStuA regulates, directly or indirectly, the expression of several effector genes in L. maculans or that the infection stage in which effectors are expressed is not reached when LmStuA expression is silenced.
Assessing pyloric sphincter pathophysiology using EndoFLIP in patients with gastroparesis
Authors: Malik Z. , Sankineni A. , Parkman H. P.
Published: February 2015

Background

Pyloric dysfunction has been associated with gastroparesis, particularly diabetic gastroparesis. Endoscopic functional luminal imaging probe (EndoFLIP) uses 16 sensors inside a balloon that is inflated inside a sphincter to assess physiologic characteristics. The aim of this study was to measure the pressure, diameter, cross‐sectional area (CSA), and distensibility of the pylorus using EndoFLIP in patients with gastroparesis. In addition, the relationship between pyloric pathophysiology with gastroparesis etiology, symptoms, and gastric emptying was assessed.

Methods

EndoFLIP was performed in 54 patients (39 idiopathic gastroparesis, 15 diabetic gastroparesis). The EndoFLIP catheter was passed endoscopically so that the balloon straddled the pylorus. Pressure, diameter, CSA, and distensibility of the pylorus were measured at 20, 30, 40, and 50 cc balloon volume.

Key Results

Pyloric sphincter contour was seen best at 40 cc balloon distension (diameter 12.2 ± 0.44 mm, CSA 125.2 ± 9.15 mm2, pressure 18.0 ± 1.23 mmHg, length 1.59 ± 0.34 cm, distensibility 10.7 ± 2.57 mm2/mmHg). There was a wide range seen in diameter (5.6–22.1 mm) and distensibility (1–55 mm2/mmHg) of the pylorus. Symptoms of early satiety and postprandial fullness were inversely correlated with pyloric sphincter diameter and CSA. No significant difference was seen between diabetic and idiopathic gastroparetics.

Conclusions & Inferences

EndoFLIP is a novel technique that can be used to assess pyloric physiologic characteristics. Early satiety and postprandial fullness were inversely correlated with diameter and CSA of the pyloric sphincter. No significant differences were seen comparing diabetic and idiopathic gastroparetics. This technology may be of benefit to help select patients with pyloric sphincter abnormalities.
Oxidative metabolism of chemical pollutants in marine organisms: molecular and biochemical biomarkers in environmental toxicology
Authors: Benedetti Maura , Giuliani Maria Elisa , Regoli Francesco
Published: February 2015

Oxidative stress biomarkers are widely used in marine ecotoxicology. Environmental pollutants enhance intracellular formation of oxyradicals through several mechanisms, but complex oxidative interactions occur in response to chemical mixtures. Metabolism of individual classes of pollutants can be influenced by a sophisticated network of prooxidant relationships, reciprocal and cascade effects, changes of redox‐sensitive signaling proteins, and transcription factors. Chemically mediated pathways can affect antioxidant responses at different levels, including pretranscriptional, transcriptional, protein, and catalytic functions; such mechanisms remain largely unexplored in marine organisms. Molecular responses of antioxidants are frequently not paralleled by expected biochemical changes or cellular effects, and caution is needed when interpreting the effects of environmental pollutants. Results on antioxidant variations can be influenced by mRNA stability and protein turnover, different timing for transcriptional and translational mechanisms, metabolic capability of tissues, posttranscriptional modifications of proteins, biphasic responses of antioxidant enzymes, and adaptation mechanisms to chronic pollution.
Finite Element Modelling for Assessing Effect of Acetabular Component Orientation on the Basic Stress Path above Acetabular Dome
Authors: Nie Yong , Pei Fu‐xing , Li Zong‐ming
Published: February 2015

Objective

To investigate the effect of acetabular component orientation on the basic stress path above the acetabular dome in the recommended safe zone.

Methods

A subject‐specific normal hip finite element model was generated and a convergence study carried out to determine the number of material properties for trabecular bone using a normal hip model. Four abduction angles (35°, 40°, 45° and 50°) and four anteversion angles (10°, 15°, 20° and 25°) from the recommended safe zone of acetabular cup orientation were chosen to simulate acetabular reconstruction. The distribution and level of periacetabular stress was assessed using a normal hip model as a control and 16 reconstructed acetabula in simulated single‐legged stances.

Results

The error of the average stress between plans four and five (50 and 100 materials for trabecular bone respectively) was 4.8%, which is less than the previously defined 5% error. The effect of acetabular component orientation on stress distribution in trabecular bone was not pronounced. When the acetabular component was at 15° anteversion and the abduction angle was 40° or 45°, the stress level on posterolateral cortical bone above the acetabular dome was as stable as that in the normal hip model.

Conclusions

Acetabular component orientation affects the basic stress path above the acetabular dome. Thus, orientation should be considered when attempting to restore normal biomechanics in the main load‐bearing area.
No Evidence of Superiority in Reducing Outliers of Component Alignment for Patient‐specific Instrumentation for Total Knee Arthroplasty: a Systematic Review
Authors: Zhang Qing‐meng , Chen Ji‐ying , Li Heng , Chai Wei , Ni Ming , Zhang Zhen‐dong , Yang Fan
Published: February 2015

Patient‐specific instrumentation (PSI) technology has been developed to improve alignment when implanting total knee arthroplasty (TKA) and is a new focus in the orthopaedic community. Current controversial data concerning PSI are discussed. A systematic review to compare PSI with conventional instrumentation and assess the radiographic outcomes was performed. Electronic databases (including PubMed, Medline, Embase, the Cochrane Library and the Science Citation Index database) and conference proceedings from 1950 to 2014 in the English language were searched. Data, including relevant patient characteristics, sample size, radiographic method, PSI system manufacturer and outliers of implant positioning and alignment on radiography were independently extracted from all eligible studies by two of the authors. A total of 2739 TKAs were included (1410 performed with PSI and 1329 with conventional instrumentation). There were more TCA outliers (malalignment >3°) and tibial slope outliers (malalignment >3°) in the PSI group than in the conventional group. The other radiographic outcomes assessed, including coronal, sagittal or rotational alignment outliers did not differ between the two groups. With regard to radiographic outcomes, our findings indicate that PSI technology is not superior in reducing outliers of component alignment.
A New Pathological Classification of Lumbar Disc Protrusion and Its Clinical Significance
Authors: Ma Xin‐long
Published: February 2015

Lumbar disc protrusion is common. Its clinical manifestations and treatments are closely related to the pathological changes; however, the pathological classification of lumbar disc protrusion is controversial. This article introduces a new pathological classification comprising four types of lumbar disc protrusion according to intraoperative findings. The damage‐herniation type is probably caused by injury and is characterized by soft herniation, the capsule can easily be cut and the broken disc tissue blocks overflow or is easily removed. The broken disc substances should be completely removed; satisfactory results can be achieved by minimally invasive endoscopic surgery. The degeneration‐protrusion type is characterized by hard and tough protrusions and the pathological process by degeneration and proliferative reaction. The nerve should be decompressed and relaxed with minimally invasive removal of the posterior wall; the bulged or protruded disc often need not be excised. The posterior vertebral osteochondrosis with disc protrusion type is characterized by deformity of the posterior vertebral body, osteochondral nodules and intervertebral disc protrusion. The herniated and fragmented disc tissue should be removed with partially protruding osteochondral nodules. Intervertebral disc cyst is of uncertain pathogenesis and is characterized by a cyst that communicates with the disc. Resection of the cyst under microscopic or endoscopic control can achieve good results; and whether the affected disc needs to be simultaneously resected is controversial. The new pathological classification proposed here is will aid better understanding of pathological changes and pathogenesis of lumbar disc protrusion and provides a reference for diagnosis and treatment.
Combination Treatment with Whole Body Vibration and a Kidney‐tonifying Herbal Fufang Prevent Osteoporosis in Ovariectomized Rats
Authors: Wei Qiu‐shi , Wang Hai‐bin , Wang Jun‐ling , Fang Bin , Zhou Guang‐Quan , Tan Xin , He Wei , Deng Wei‐min
Published: February 2015

Objective

To assess the ability of whole body vibration (WBV) with the kidney‐tonifying herbal Fufang (Bushen Zhuanggu Granules, BZG) to prevent osteoporosis in ovariectomized rats.

Methods

Fifty 6‐month‐old female Sprague Dawley rats were divided into five groups: sham‐operated (SHAM), ovariectomized (OVX), OVX with WBV (OVX + WBV), OVX with BZG (OVX + BZG), OVX with both WBV and BZG (OVX + WBV + BZG). The SHAM group received normal saline. After 12 weeks of treatment, the rats were killed, their serum concentrations of osteopontin (OPN), receptor activator of nuclear factor kappa‐B ligand RANKL and bone turnover markers assayed and bone mineral density (BMD), histomorphometry and bone strength evaluated.

Results

Concentrations of OPN were significantly lower in the SHAM, OVX + WBV and OVX + WBV + BZG groups at 12 weeks, whereas concentrations of RANKL had decreased significantly in the SHAM, OVX + WBV, OVX + BZG and OVX + WBV + BZG groups. In the OVX + WBV, OVX + BZG and OVX + WBV + BZG groups the amount of bone turnover had been significantly antagonized. Compared with OVX group, BMD, % trabecular area (Tb.Ar), number of trabeculae (Tb.N) and assessed biomechanical variables were higher in OVX+WBV group, whereas and BMD, %Tb.Ar, Tb.N, maximal load and yield load were higher in the OVX + BZG group. All tested indices were significantly lower in the OVX + WBV and OVX + BZG groups than in the OVX + WBV + BZG group.

Conclusion

Either WBV or BZG alone prevents OVX‐induced bone loss. However, BZG enhances the effect of WBV by further enhancing BMD, bone architecture and strength.
Manipulating microRNAs for improved biomass and biofuels from plant feedstocks
Authors: Trumbo Jennifer Lynn , Zhang Baohong , Stewart Charles Neal
Published: February 2015

Petroleum‐based fuels are nonrenewable and unsustainable. Renewable sources of energy, such as lignocellulosic biofuels and plant metabolite‐based drop‐in fuels, can offset fossil fuel use and reverse environmental degradation through carbon sequestration. Despite these benefits, the lignocellulosic biofuels industry still faces many challenges, including the availability of economically viable crop plants. Cell wall recalcitrance is a major economic barrier for lignocellulosic biofuels production from biomass crops. Sustainability and biomass yield are two additional, yet interrelated, foci for biomass crop improvement. Many scientists are searching for solutions to these problems within biomass crop genomes. MicroRNAs (miRNAs) are involved in almost all biological and metabolic process in plants including plant development, cell wall biosynthesis and plant stress responses. Because of the broad functions of their targets (e.g. auxin response factors), the alteration of plant miRNA expression often results in pleiotropic effects. A specific miRNA usually regulates a biologically relevant bioenergy trait. For example, relatively low miR156 overexpression leads to a transgenic feedstock with enhanced biomass and decreased recalcitrance. miRNAs have been overexpressed in dedicated bioenergy feedstocks such as poplar and switchgrass yielding promising results for lignin reduction, increased plant biomass, the timing of flowering and response to harsh environments. In this review, we present the status of miRNA‐related research in several major biofuel crops and relevant model plants. We critically assess published research and suggest next steps for miRNA manipulation in feedstocks for increased biomass and sustainability for biofuels and bioproducts.
Genome‐wide association of drought‐related and biomass traits with HapMap SNPs in Medicago truncatula
Authors: Kang Yun , Sakiroglu Muhammet , Krom Nicholas , Stanton‐Geddes John , Wang Mingyi , Lee Yi‐Ching , Young Nevin D. , Udvardi Michael
Published: February 2015

Improving drought tolerance of crop plants is a major goal of plant breeders. In this study, we characterized biomass and drought‐related traits of 220 Medicago truncatula HapMap accessions. Characterized traits included shoot biomass, maximum leaf size, specific leaf weight, stomatal density, trichome density and shoot carbon‐13 isotope discrimination (δ13C) of well‐watered M. truncatula plants, and leaf performance in vitro under dehydration stress. Genome‐wide association analyses were carried out using the general linear model (GLM), the standard mixed linear model (MLM) and compressed MLM (CMLM) in TASSEL, which revealed significant overestimation of P‐values by CMLM. For each trait, candidate genes and chromosome regions containing SNP markers were found that are in significant association with the trait. For plant biomass, a 0.5 Mbp region on chromosome 2 harbouring a plasma membrane intrinsic protein, PIP2, was discovered that could potentially be targeted to increase dry matter yield. A protein disulfide isomerase‐like protein was found to be tightly associated with both shoot biomass and leaf size. A glutamate‐cysteine ligase and an aldehyde dehydrogenase family protein with Arabidopsis homologs strongly expressed in the guard cells were two of the top genes identified by stomata density genome‐wide association studies analysis.
Role of the Keap1/Nrf2 pathway in neurodegenerative diseases
Authors: Yamazaki Hiromi , Tanji Kunikazu , Wakabayashi Koichi , Matsuura Shin , Itoh Ken
Published: February 2015

As the elderly population increases, a growing number of individuals suffer from age‐associated neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). Oxidative stress is considered to play a crucial role in the pathogenesis of age‐related diseases. The transcription factor Nrf2 (nuclear factor erythroid 2‐related factor 2) is activated by oxidative stress and regulates the expression of a variety of antioxidant enzymes and proteins that exert cytoprotective effects against oxidative stress. Numerous studies have addressed the role of Nrf2 in age‐related diseases, including neurodegenerative diseases, using animal or in vitro cell culture models. Here, we introduce the role of oxidative stress in the pathogenesis of neurodegenerative diseases and critically examine the recent findings concerning the role for Nrf2 in the amelioration of AD and PD. Nrf2 not only regulates antioxidant proteins but also regulates the genes associated with autophagy and nerve growth factor signaling. Current research unequivocally demonstrates that the activation of the Nrf2 pathway is a promising novel strategy for the prevention and modification of neurodegenerative diseases.
Advances in pathology of diabetes from pancreatic islets to neuropathy—a tribute to Paul Langerhans
Authors: Yagihashi Soroku
Published: February 2015

There emerges a world epidemic of diabetes, afflicting over 3.8 billion people globally. The socio‐economic burden of this disorder is tremendous and there is an urgent need to solve the problems incurred from this disorder and to establish an efficient way of prevention and treatment. Fundamental pathology of diabetes has been too diverse to reach a simple etiology and the mechanisms of how the lesions specific to diabetes develop are yet to be clear. Nevertheless, there has been slow but significant advancement in the understanding of the disease based on characterization of the salient features of pathological lesions in human diabetic subjects. Progressive decline of islet β cells associated with increased α cell volume density was found to account for clinical manifestation of hypoinsulinemia and hyperglucagonemia in type 2 diabetes. Concurrently, signs of complications represented by distal nerve fiber loss in the skin commences from the beginning of this disease. Thus the pathological studies disclosed the major attributes in this disorder targeting the islet of pancreas and epidermal nerve, both of which were discovered by Paul Langerhans more than 140 years ago. In this review, I attempt to summarize the progress in pathology of diabetes which Langerhans opened this field.
Anaplastic lymphoma kinase translocation is correlated with anaplastic lymphoma kinase expression and mutually exclusive with epidermal growth factor receptor mutation in Taiwanese non‐small cell lung cancer
Authors: Hsu Sheng‐Chi , Hung Tsai‐Hsien , Wang Chih‐Wei , Ng Kwai‐Fong , Chen Tse‐Ching
Published: February 2015

The echinoderm microtubule‐associated protein‐like 4‐anaplastic lymphoma kinase (EML4‐ALK) fusion gene is an important biomarker for target therapy. The aim of this study is to better understand the clinical and molecular features of the EML4‐ALK fusion gene in lung cancer patients in Taiwan and therefore to generate an efficient algorithm for the detection of ALK translocation. In the first cohort, ALK translocation was identified in 1 adenocarcinoma from 100 lung cancer patients by using break apart fluorescent in situ hybridization (FISH). Next, we detected 6 ALK translocations in another 40 EGFR wild type adenocarcinomas but not in 40 cases with EGFR mutation. Histological analysis revealed that solid growth with signet‐ring cells or cribriform glands with extracellular mucin were noted in all the 7 ALK translocated cases. One ALK positive cancer with mucinous cribriform pattern had no ALK expression. ALK expression was correlated with ALK translocation (p < 0.001), but not with ALK gene copy number gain (CNG) (P = 0.838). ALK translocation was also mutually exclusive with EGFR mutation in Taiwanese non‐small cell lung cancer (P = 0.033). These results indicate that screening tests for EGFR mutation status and/or ALK expression could help efficiently select ALK translocated patients for target therapy.
CONVERGENCE IN PROVINCIAL‐LEVEL SOUTH AFRICAN HOUSE PRICES: EVIDENCE FROM THE CLUB CONVERGENCE AND CLUSTERING PROCEDURE
Authors: Apergis Nicholas , Simo‐Kengne Beatrice D. , Gupta Rangan
Published: February 2015

This empirical study analyzes the long run behavior of provincial house prices in South Africa based on the club convergence and clustering procedure of Phillips and Sul. Using quarterly data covering the period of 1976Q2–2012Q4, 1974Q1–2012Q4 and 1977Q3–2012Q4 for the large, medium, and small middle segments of the housing market, respectively, we test the law of one price across nine provinces. The empirical findings suggest that the nine provinces do not form a homogeneous convergence club. Unlike the small middle segment, which consists of two convergence clubs of seven and two provinces, the large and medium middle segments have three convergence clubs corresponding to three segmented independent local markets. Possible intuitive explanations for the existence of such clubs are discussed and resulting policy implications provided.
ECONOMIC LIBERALIZATION AND GENDER INEQUALITY IN THE LABOR MARKET: A THEORETICAL APPROACH
Authors: Mukhopadhyay Ujjaini
Published: February 2015

The paper seeks to provide a theoretical foundation to the diverse empirical findings with regard to the role of liberalization in perpetuating gender inequality in the labor market. It studies the role of female labor supply decisions on gender wage inequality by considering the interrelation between liberalized policies, gender wage inequality, and female labor force participation. A three–sector Harris‐Todaro general equilibrium model has been developed to examine the effects of liberalized trade, investment, and labor market policies on the gender wage gap and female labor force participation. There are two underlying assumptions: first, women are paid less because they are employed in the informal sectors; even within the informal sector, they are engaged in particularly low paying activities because of gender segregation. Second, female labor supply decisions or female labor force participation is endogenous, and depends on male and female wages, and the unemployment of male workers. The comparative static analysis indicates that while a reduction in import tariff may narrow the gender wage gap and raise female workforce participation, foreign capital inflow and labor market deregulation may aggravate gender wage inequality and lower female labor force participation.
Iterative Scaling in Curved Exponential Families
Authors: Klimova Anna , Rudas Tamás
Published: February 2015

The paper describes a generalized iterative proportional fitting procedure that can be used for maximum likelihood estimation in a special class of the general log‐linear model. The models in this class, called relational, apply to multivariate discrete sample spaces that do not necessarily have a Cartesian product structure and may not contain an overall effect. When applied to the cell probabilities, the models without the overall effect are curved exponential families and the values of the sufficient statistics are reproduced by the MLE only up to a constant of proportionality. The paper shows that Iterative Proportional Fitting, Generalized Iterative Scaling, and Improved Iterative Scaling fail to work for such models. The algorithm proposed here is based on iterated Bregman projections. As a by‐product, estimates of the multiplicative parameters are also obtained. An implementation of the algorithm is available as an R‐package.
Innate and adaptive genetic pathways in HCV infection
Authors: Buchanan R. , Hydes T. , Khakoo S. I.
Published: February 2015

Infection with hepatitis C virus (HCV) leads to a wide spectrum of clinical manifestations. This heterogeneity is underpinned by the host immune response and the genetic factors that govern it. Polymorphisms affecting both the innate and adaptive immunity determine the outcome of exposure. However the innate immune system appears to play a greater role in determining treatment‐associated responses. Overall the effects of IFNL3/4 appear dominant over other polymorphic genes. Understanding how host genetics determines the disease phenotype has not been as intensively studied. This review summarizes our current understanding of innate and adaptive immunogenetic factors in the outcome of HCV infection. It focuses on how they relate to resolution and the progression of HCV‐related liver disease, in the context of current and future treatment regimes.
Monetary Policy Independence under Flexible Exchange Rates: An Illusion?
Authors: Edwards Sebastian
Published: February 2015

I analyse whether countries with flexible exchange rates are able to pursue an independent monetary policy, as suggested by traditional theory. I use data for three Latin American countries with flexible exchange rates, inflation targeting and capital mobility – Chile, Colombia and Mexico – to investigate the extent to which Federal Reserve actions are translated into local central banks' policy rates. The results indicate that there is significant ‘policy contagion’ and that these countries tend to ‘import’ Fed policies. The degree of monetary policy independence is lower than what traditional models suggest.
A Multibody Dynamic Model of Drillstring for Torque and Drag Analysis
Authors: Caijin Yang , Zaibin Cheng , Wei Jang , Shiquan Jiang , Gexue Ren
Published: February 2015

Excessive torque and drag in the wellbore can result in the buckling and the failure of the drillstring. Accurate predicting torque and drag is important in drilling operations. Due to the nature of the drilling, determination of torque and drag is a dynamic problem. A multibody dynamic model of the drillstring for the torque and drag analysis is developed here. Unlike traditional softstring models and stiffstring models, the developed model relaxes the assumption of continuous contact between the drillstring and the wellbore. Moreover, this model can account for overall rigid motion, three-dimensional (3D) rotation and large deformation of the drillstring with large-scale slenderness ratio and random contact between the drillstring and the wellbore. The effects of local protuberant components of the drillstring, such as the drillpipe subs and the stabilizers are also incorporated in the current model, which are not considered in most of existing models. Numerical analysis with three cases is carried out to show the application of the developed model in predicting torque and drag in the wellbore.
Application of a Three-Dimensional Computational Wrist Model to Proximal Row Carpectomy
Authors: Wayne Jennifer S. , Mir Afsarul Q.
Published: February 2015

A three-dimensional (3D) computational model of the wrist examined the biomechanical effects of the proximal row carpectomy (PRC), a surgical treatment of certain wrist degenerative conditions but with functional consequences. Model simulations, replicating the 3D bony anatomy, soft tissue restraints, muscle loading, and applied perturbations, demonstrated quantitatively accurate responses for the decreased motions subsequent to the surgical procedure. It also yielded some knowledge of alterations in radiocarpal contact force which likely increase contact pressure as well as additional insight into the importance of the triangular fibrocartilage complex and retinacular/capsular structures for stabilizing the deficient wrist. As better understanding of the wrist joint is achieved, this model could serve as a useful clinical tool.
Molecular dynamic simulation of damage formation at Si vertical walls by grazing incidence of energetic ions in gate etching processes
Authors: Mizotani Kohei , Isobe Michiro , Hamaguchi Satoshi
Published: February 2015

During gate etching processes of multigate fin-type field effect transistors (finFETs), energetic ions may hit the vertical walls at grazing angles and form damaged layers there. Such damages, if formed, can affect the device performance since part of the Si vertical walls of a finFET structure is used as a conductive channel. In this article, possible damage formation mechanisms at a Si vertical wall by energetic incidence of hydrogen ions (H+) and other heavier ions are discussed based on molecular dynamics simulation. In typical plasma processing conditions, incident ions are highly directional toward the wafer surface and therefore ions that hit such a vertical wall do so only at nearly grazing angles. It has been found in this study that the penetration depth of H+ into a Si substrate is weakly dependent on the incident angle and therefore ions at grazing incidence can form deep damage. The results indicate that, in gate etching processes with HBr plasmas or other plasmas with hydrogen, control of energetic hydrogen ion bombardment is critical in minimizing possible surface damage at Si vertical walls.
Consecutive Days of Prolonged Tennis Match Play: Performance, Physical, and Perceptual Responses in Trained Players
Authors: Gescheit Danielle T. , Cormack Stuart J. , Reid Machar , Duffield Rob
Published: February 2015

Purpose:

To determine how consecutive days of prolonged tennis match play affect performance, physiological, and perceptual responses.

Methods:

Seven well-trained male tennis players completed 4-h tennis matches on 4 consecutive days. Pre- and postmatch measures involved tennis-specific (serve speed and accuracy), physical (20-m sprint, countermovement jump [CMJ], shoulder-rotation maximal voluntary contraction, isometric midthigh pull), perceptual (Training Distress Scale, soreness), and physiological (creatine kinase [CK]) responses. Activity profile was assessed by heart rate, 3D load (accumulated accelerations measured by triaxial accelerometers), and rating of perceived exertion (RPE). Statistical analysis compared within- and between-days values. Changes (± 90% confidence interval [CI]) ≥75% likely to exceed the smallest important effect size (0.2) were considered practically important.

Results:

3D load reduced on days 2 to 4 (mean effect size ± 90% CI –1.46 ± 0.40) and effective playing time reduced on days 3 to 4 (–0.37 ± 0.51) compared with day 1. RPE did not differ and total points played only declined on day 3 (–0.38 ± 1.02). Postmatch 20-m sprint (0.79 ± 0.77) and prematch CMJ (–0.43 ± 0.27) performance declined on days 2 to 4 compared with prematch day 1. Although serve velocity was maintained, compromised postmatch serve accuracy was evident compared with prematch day 1 (0.52 ± 0.58). CK increased each day, as did ratings of muscle soreness and fatigue.

Conclusions:

Players reduced external physical loads, through declines in movement, over 4 consecutive days of prolonged competitive tennis. This may be affected by tactical changes and pacing strategies. Alongside this, impairments in sprinting and jumping ability, perceptual and biochemical markers of muscle damage, and reduced mood states may be a function of neuromuscular and perceptual fatigue.
The Effects of Red Bull Energy Drink Compared With Caffeine on Cycling Time-Trial Performance
Authors: Quinlivan Alannah , Irwin Christopher , Grant Gary D. , Anoopkumar-Dukie Sheilandra , Skinner Tina , Leveritt Michael , Desbrow Ben
Published: February 2015

This study investigated the ergogenic effects of a commercial energy drink (Red Bull) or an equivalent dose of anhydrous caffeine in comparison with a noncaffeinated control beverage on cycling performance. Eleven trained male cyclists (31.7 ± 5.9 y 82.3 ± 6.1 kg, V̇O2max = 60.3 ± 7.8 mL · kg–1 · min–1) participated in a double-blind, placebo-controlled, crossover-design study involving 3 experimental conditions. Participants were randomly administered Red Bull (9.4 mL/kg body mass [BM] containing 3 mg/kg BM caffeine), anhydrous caffeine (3 mg/kg BM given in capsule form), or a placebo 90 min before commencing a time trial equivalent to 1 h cycling at 75% peak power output. Carbohydrate and fluid volumes were matched across all trials. Performance improved by 109 ± 153 s (2.8%, P = .039) after Red Bull compared with placebo and by 120 ± 172 s (3.1%, P = .043) after caffeine compared with placebo. No significant difference (P > .05) in performance time was detected between Red Bull and caffeine treatments. There was no significant difference (P > .05) in mean heart rate or rating of perceived exertion among the 3 treatments. This study demonstrated that a moderate dose of caffeine consumed as either Red Bull or in anhydrous form enhanced cycling time-trial performance. The ergogenic benefits of Red Bull energy drink are therefore most likely due to the effects of caffeine, with the other ingredients not likely to offer additional benefit.
The Relationship Between Start Performance and Race Outcome in Elite 500-m Short-Track Speed Skating
Authors: Haug William B. , Drinkwater Eric J. , Mitchell Lachlan J. , Chapman Dale W.
Published: February 2015

Initial short-track speed-skating 14-m start performance has substantial influence on 500-m race outcome at the international level, yet the relationship has not been systematically quantified. The purpose of this investigation was to examine the relationship between rank position entering first corner (RPEFC) and race outcome and to understand how this relationship changes with competition round and absolute race intensity. Data were compiled from 2011–2014 World Cup seasons and 2010 and 2014 Olympic Winter Games. Association between RPEFC and race outcome was determined through Kendall tau-rank correlations. A visual comparison was made of how the relationship changes with relative competition level (race tau correlations were sorted by competition round) and with race intensity (race tau correlations were sorted by within-event winning time). A very large relationship between RPEFC and race outcome was observed (correlations for cohort, τ = .60; men, τ = .53; women, τ = .67). When examined by competition round (quarter- to A-finals), no substantial change in relationship was observed (men, τ = .57–.46; women, τ = .73–.53). However, when the start–performance relationship was considered by within-event winning time, the relationship strength increased with decreasing time (men, τ = .61 to .46; women, τ = .76 to .57; fastest to 7th- and 8th-fastest combined, respectively). These results establish and quantify RPEFC as an important aspect of elite short-track 500-m race outcome. RPEFC as an indicator of race outcome becomes increasingly important with absolute race intensity, suggesting that RPEFC capability is a discriminating factor for competitors of similar top speed and speed endurance.
Standardization of the Dmax Method for Calculating the Second Lactate Threshold
Authors: Chalmers Samuel , Esterman Adrian , Eston Roger , Norton Kevin
Published: February 2015

Purpose:

The purpose of this study was to test the reliability and validity of 2 standardized methods for calculating speed at the second lactate-threshold point (LT2) based on the preexisting Dmax (LTD) and modified Dmax (LTMOD) procedures.

Methods:

13 trained male road runners and triathletes completed 2 incremental laboratory running tests to determine LT2, followed by separate time trials (5, 10, 15 km) on an outdoor running track. Two new methods were proposed for calculating the speed at LT2: (1) the single standardized lactate threshold (LTSDs) and (2) the paired standardized lactate threshold (LTSDp) for quantifying changes over time.

Results:

The LTSDs and LTSDp methods had high relative (ICC ≥ .98) and absolute (CV ≤ 1.9%) reliability in identifying the speed at LT2. The speed at LT2 according to the LTSDs and LTSDp methods had a strong correlation and was not different to the performance speed during the 10- and 15-km time trials (≤2.3%; ρc > 0.8; P > .05). The following natural logbased formula was created to estimate the percentage of LT2 speed (using the LTSDs method) that could be sustained for events ~15–75 min: y = –7.256(ln x) + 157.64, where y = %LT2 speed, x = time-trial performance (s), and ln = natural log.

Conclusions:

The standardized methods are reliable for determining LT2. The LTSDs and LTSDp methods for calculating the speed at LT2 from a near-maximal incremental test calculated speeds similar to those exhibited in 10- and 15-km running time trials. A prediction equation for estimating the percentage of LT2 that can be sustained for events of ~15–75 min was generated.
Sleep Disorders, Physical Activity, and Sedentary Behavior Among U.S. Adults: National Health and Nutrition Examination Survey
Authors: Farnsworth James L. , Kim Youngdeok , Kang Minsoo
Published: February 2015

Background:

Disruptive sleeping patterns have been linked to serious medical conditions. Regular physical activity (PA) has a positive impact on health; however, few research have investigated the relationships between PA, body mass index (BMI), sedentary behaviors (SB), and sleep disorders (SD).

Methods:

Data from the 2005–2006 NHANES were analyzed for this study. Participants (N = 2989; mean age = 50.44 years) were grouped based upon responses to SD questions. Accelerometers were used to measure the average time spent in moderate or vigorous physical activity (MVPA) and SB. Multinomial logistic regression analyses were used to examine the associations between PA, SB, and SD after controlling for covariates and to explore potential moderation effects among common risk factors and the main study variables.

Results:

Among middle-aged adults, PA was significantly associated with SD [Wald χ2 (8) = 22.21; P < .001]. Furthermore, among adults in the highest tertile of SB, PA was significantly associated with SD [Wald χ2 (8) = 32.29; P < .001].

Conclusions:

These results indicate that middle-aged adults who are less active may have increased likelihoods of SD. It is important for health care professionals to continue developing methods for increasing PA to decrease the risk of SD.
Systematic inequality and hierarchy in faculty hiring networks
Authors: Clauset Aaron , Arbesman Samuel , Larremore Daniel B.
Published: February 2015

An analysis of networks of graduate-to-faculty hires reveals systematic hiring biases and patterns.