bluuebunny/crossref_metadata_2025 huggingface dataset:
Angiogenesis and Collagen Type IV Expression in Different Endothelial Cell Culture Systems
Authors: Bahramsoltani M. , Slosarek I. , De Spiegelaere W. , Plendl J.
Published: April 2013

In vitro angiogenesis assays constitute an important tool for studying the mechanisms of angiogenesis and for identification of pro‐ and anti‐angiogenic substances. Therefore, endothelial cell and media systems used for in vitro angiogenesis assays are required to mimic the angiogenic process in vivo including endothelial capability to express collagen type IV as a component of the basement membrane. In this study, the expression of collagen type IV and its α chains (α1‐6) was investigated in different endothelial cell culture systems in vitro qualitatively and quantitatively. These systems included four different batches of microvascular endothelial cells derived from the human skin, heart and lung, from which only two batches were found to be angiogenic and two batches were classified as non‐angiogenic. Distribution of the transcripts of the α chains of collagen type IV was similar in all cell and media systems investigated. However, secretion and deposition of a stable extracellular network of collagen type IV could only be observed in the angiogenic cultures. In conclusion, the consecutive steps of the angiogenic cascade in vivo as well as in vitro depend on an increasing secretion and subsequent extracellular deposition of collagen type IV.
Young people's participation in Fiji: Merits, challenges and the way forward
Authors: Vakaoti Patrick
Published: April 2013

Young people's participation is central to the attainment of meaningful governance systems. In Fiji, this is a challenge as the traditional view of young people's participation is restricted to that of ‘service’ and the precarious political environment restricting free expression. Despite these concerns, young people's participation and expression appear to be thriving in hybridised forms. This paper draws from conversations with a group of ‘active’ young people and discusses the merits and challenges of their participation in Fiji. As a nation, Fiji is at the threshold of a new socio‐political era, where young people are expected to play a significant role. This discussion offers an understanding of young people's participation in Fiji and draws attention to how they can be meaningfully supported as active citizens in the process of national development.
Of mice, men, and King Tut: autosomal recessive Klippel–Feil syndrome is caused by mutations in MEOX1
Authors: Rosti RO
Published: April 2013

Mutations in MEOX1, encoding mesenchyme homeobox 1, cause Klippel‐Feil anomaly.

Jawahir et al. (2013)

The American Journal of Human Genetics 92: 157–161
External negative electric potential accelerates exocytosis of lamellar bodies in human skin ex vivo
Authors: Kumamoto Junichi , Goto Makiko , Denda Sumiko , Nakatani Masashi , Takasugi Yuya , Tsuchiya Katsunori , Shimizu Yuji , Takatsuru Yusuke , Denda Mitsuhiro
Published: April 2013

Exocytosis of lamellar bodies at the uppermost nucleated layer of the epidermis is a crucial process for epidermal permeability barrier homoeostasis. We have previously suggested that skin surface electric potential might be associated with barrier homoeostasis. Thus, we hypothesized that the potential might drive exocytosis of lamellar bodies. In this study, we tested this idea by applying negative electric potential (−0.5 V) to human skin samples ex vivo for 2 h and observing the ultrastructure of the uppermost layer. The secretion of lamellar bodies was accelerated in the potential‐applied skin, compared to that in untreated control skin. Multiphoton observation indicated that extracellular lipid domains were more extensive in treated skin than in control skin. Moreover, the calcium ion gradient was greater at the uppermost layer of the epidermis of treated skin, compared to that in control skin. These results indicate that electric potential may regulate lamellar body secretion in healthy human skin.
Migrate or evolve: options for plant pathogens under climate change
Authors: Chakraborty Sukumar
Published: April 2013

Findings on climate change influence on plant pathogens are often inconsistent and context dependent. Knowledge of pathogens affecting agricultural crops and natural plant communities remains fragmented along disciplinary lines. By broadening the perspective beyond agriculture, this review integrates cross‐disciplinary knowledge to show that at scales relevant to climate change, accelerated evolution and changing geographic distribution will be the main implications for pathogens. New races may evolve rapidly under elevated temperature and CO2, as evolutionary forces act on massive pathogen populations boosted by a combination of increased fecundity and infection cycles under favourable microclimate within enlarged canopy. Changing geographic distribution will bring together diverse lineages/genotypes that do not share common ecological niche, potentially increasing pathogen diversity. However, the uncertainty of model predictions and a lack of synthesis of fragmented knowledge remain as major deficiencies in knowledge. The review contends that the failure to consider scale and human intervention through new technology are major sources of uncertainty. Recognizing that improved biophysical models alone will not reduce uncertainty, it proposes a generic framework to increase focus and outlines ways to integrate biophysical elements and technology change with human intervention scenarios to minimize uncertainty. To synthesize knowledge of pathogen biology and life history, the review borrows the concept of ‘fitness’ from population biology as a comprehensive measure of pathogen strengths and vulnerabilities, and explores the implications of pathogen mode of nutrition to fitness and its interactions with plants suffering chronic abiotic stress under climate change. Current and future disease management options can then be judged for their ability to impair pathogenic and saprophytic fitness. The review pinpoints improving confidence in model prediction by minimizing uncertainty, developing management strategies to reduce overall pathogen fitness, and finding new sources of data to trawl for climate signatures on pathogens as important challenges for future research.
The temporal response to drought in a Mediterranean evergreen tree: comparing a regional precipitation gradient and a throughfall exclusion experiment
Authors: Martin‐StPaul Nicolas K. , Limousin Jean‐Marc , Vogt‐Schilb Hélène , Rodríguez‐Calcerrada Jesus , Rambal Serge , Longepierre Damien , Misson Laurent
Published: April 2013

Like many midlatitude ecosystems, Mediterranean forests will suffer longer and more intense droughts with the ongoing climate change. The responses to drought in long‐lived trees differ depending on the time scale considered, and short‐term responses are currently better understood than longer term acclimation. We assessed the temporal changes in trees facing a chronic reduction in water availability by comparing leaf‐scale physiological traits, branch‐scale hydraulic traits, and stand‐scale biomass partitioning in the evergreenQuercus ilexacross a regional precipitation gradient (long‐term changes) and in a partial throughfall exclusion experiment (TEE, medium term changes). At the leaf scale, gas exchange, mass per unit area and nitrogen concentration showed homeostatic responses to drought as they did not change among the sites of the precipitation gradient or in the experimental treatments of theTEE. A similar homeostatic response was observed for the xylem vulnerability to cavitation at the branch scale. In contrast, the ratio of leaf area over sapwood area (LA/SA) in young branches exhibited a transient response to drought because it decreased in response to theTEEthe first 4 years of treatment, but did not change among the sites of the gradient. At the stand scale, leaf area index (LAI) decreased, and the ratios of stem SA toLAIand of fine root area toLAIboth increased in trees subjected to throughfall exclusion and from the wettest to the driest site of the gradient. Taken together, these results suggest that acclimation to chronic drought in long‐livedQ. ilexis mediated by changes in hydraulic allometry that shift progressively from low (branch) to high (stand) organizational levels, and act to maintain the leaf water potential within the range of xylem hydraulic function and leaf photosynthetic assimilation.
Clinical Satisfaction and Quality of Ceramic Fixed Dentures
Authors: Goiato Marcelo Coelho , Pesqueira Aldiéris Alves , Monteiro Douglas Roberto , de Faria Almeida Daniel Augusto , dos Santos Daniela Micheline
Published: April 2013

It is known that several factors can affect the clinical success and durability of fixed partial dentures. Therefore, the aim of the present study was to present a literature review about the longevity, clinical success, and quality, as well as, patients' and dental surgeons' satisfaction of ceramic fixed dentures. High rate of patients' satisfaction has been observed in relation to the esthetic of ceramic crowns. In addition, the literature has shown that dental ceramics can be used in several clinical situations with high success rate and longevity. Despite of failures and complications of ceramic restorations, nowadays, with the improvement of mechanical properties of such materials, ceramic crowns present a favorable prognosis and can be used in several clinical situations with high success rate, clinical quality, and great patients' satisfaction.
Texas Roundtable on: The Future of Graduate Business School Education
Authors: Sandefer Jeff , Gilligan Tom , Dewan Rajiv , Petty Bill , Naples Ron , Martin John , Chew Don
Published: April 2013

A small group of academics and practitioners discuss the challenges now facing today's business schools. First and foremost is the challenge now being mounted by “online” courses to the traditional methods of classroom lecture and discussion, supplemented in some cases by apprenticeships and other kinds of “experiential” learning. How will traditional universities burdened with high and rising fixed costs for buildings and faculty compete with very low‐cost competitors—programs that reportedly have enabled star lecturers to reach audiences that, in some cases, have exceeded 100,000 students?

In assessing the seriousness of the challenge, the panelists start by attempting to articulate what is valuable in current business school education—valuable enough to enable the best business schools to command as much as $175,000 for two‐year (or shorter) programs that confer MBAs. Much of the discussion focuses on establishing the relative importance of the disciplines, or body of knowledge, that are taught in business schools, as compared to the development of “collaborative” habits and interpersonal skills aimed at enabling students to make more effective use of their knowledge within large organizations. Some of the panelists, notably Jeff Sandefer, founder of the (now ten‐year old) Acton School of Business, argue that far too much of today's business school curriculum is devoted to the classroom and conventional learning. And many of the changes in the top business schools during the past decade appear to reflect Sandefer's charges. But, to the extent there is a consensus among the other panelists, it is that the best business schools will continue to try to accomplish both of these goals, though with varying degrees of effectiveness, while most schools attempt to maintain their specialized capabilities, and carve out distinctive niches based on them. For some schools, such specialization is likely to mean continued emphasis on theory and classroom learning—though almost certainly with more attention to practical application and collaborative decision‐making. For other schools, the main focus will continue to be the development of general management and leadership skills.
Corporate Governance and Value: Evidence from “Close Calls” On Shareholder Governance Proposals
Authors: Cuñat Vicente , Gine Mireia , Guadalupe Maria
Published: April 2013

The authors summarize the findings of their recent study of the effects of specific corporate governance provisions on firm value. Using a sample of governance provisions that were subjected to shareholder votes during the period 1997–2011, this study analyzes cases in which shareholder‐sponsored corporate governance proposals were either rejected or passed by a small margin (no more than 5% of the vote). By so doing, this study helps correct two limitations of the existing governance literature: (1) that the effects of expected governance changes are already incorporated in share prices (the “expectations” problem); and (2) that governance policies are often a consequence rather than a cause of other variables such as corporate performance and are thus correlated with many other firm characteristics (the “endogeneity” problem).

The authors' findings show that expected improvements in corporate governance through the adoption of particular corporate governance provisions—particularly the removal of anti‐takeover provisions—is associated with both positive abnormal stock returns and improvements in long‐term firm operating performance. The authors estimate that the adoption of such governance proposals increases shareholder value by 2.6%, on average. Moreover, these returns are consistent with, and thus accurate predictors of, future changes in corporate investment (reductions of capital spending, in most cases) and improvements in operating performance.
Genetic evaluation of remnant and translocated shiners, Notropis heterodon and Notropis heterolepis
Authors: Ozer F. , Ashley M. V.
Published: April 2013

Population and conservation genetics of two freshwater fish species, Notropis heterodon and Notropis heterolepis, were evaluated in north‐eastern Illinois, U.S.A., where both species have severely declined. Fishes were sampled from two remnant populations occurring in small glacial lakes (source samples) and from two man‐made ponds that had been stocked with fishes from those same lakes (sanctuary samples). The goal was to obtain information that would help inform conservation programme planning to reintroduce sanctuary fishes to areas where both species are extirpated. Microsatellite data showed that the two species were genetically quite distinct and there was no evidence of hybridization in either source or sanctuary samples. Within each species, source and sanctuary samples had moderate levels of heterozygosity and were not significantly different from each other. Many alleles observed in the source samples, however, were not detected in the sanctuary samples, indicating that translocation had resulted in reduced allelic diversity of the sanctuary samples. Sibship analysis indicated that full and half sibs occurred within source‐lake samples, thus reducing the effective population size of the reintroduced stock. Taken together, these results suggest that source‐lake stocks rather than sanctuary stocks are more appropriate for future reintroductions of both species in their native range, unless sanctuary populations can be established with hundreds of fishes. Also, fishes should be harvested from multiple locations in source lakes to avoid over‐representation of family groups.
Neuropeptide Y in black seabream Acanthopagrus schlegelii: identification, distribution and mRNA expression responses to ghrelin
Authors: Ma X. L. , Zheng L. W. , Mao L. T. , Zhou L. B. , Wang A. L.
Published: April 2013

The coding region of neuropeptide Y (NPY) complementary (c)DNA was cloned from the hypothalamus RNA of black seabream Acanthopagrus schlegelii, including 297 bp coding for prepro‐NPY of 98 amino acids. Real‐time reverse transcriptase‐polymerase chain reaction was performed to determine A. schlegelii npy gene expression; NPY messenger RNA (mRNA) was expressed highly in the brain and stomach. Treatment with acylated ghrelin significantly up‐regulated NPY mRNA level in the hypothalamus, suggesting that NPY may be involved in regulating food intake of A. schlegelii.
Development of the Parental Self‐Efficacy Scale for Child Autonomy toward Minor Surgery (PSESCAMS): Based on results of questionnaire surveys of parents raising children between 3 and 6 years old
Authors: Ono Satomi , Manabe Yukiko
Published: April 2013

Aim

The aim of this study is to prepare the Parental Self‐Efficacy Scale for Child Autonomy toward Minor Surgery (PSESCAMS) and verify its reliability and validity.

Methods

The PSESCAMS was developed based on the findings of previous qualitative studies on preschool children aged 3–6 years who were undergoing day surgery and their parents. The Generalized Self‐Efficacy Scale, Maternal Self‐Accomplishment Scale (MSAS), and Japanese‐language version of the State–Trait Anxiety Inventory A‐trait subscale (STAI: A‐trait) were used to examine the criterion‐related validity of the PSESCAMS. In addition, the test–retest method was utilized for the PSESCAMS.

Results

The number of valid responses was 586. A principle component analysis of the PSESCAMS was conducted of 18 items, extracting two factors. As a result of factor analysis that assumed two factors, the two factors were named “self‐efficacy for support related to child's emotional control for minor surgery” and “self‐efficacy for support related to child's understanding of minor surgery”. A structural equation model having high goodness of fit for the PSESCAMS was shown by a covariance structure analysis. The correlations between GSES, MSAS, STAI: A‐trait and the PSESCAMS were r = 0.323 (P < 0.001), r = 0.370 (P < 0.001), and r = −0.248 (P < 0.001), respectively. Cronbach's alpha of both the initial test and the test–retest for the PSESCAMS were 0.9 and the correlation between both was significant.

Conclusion

The PSESCAMS consists of two categories and includes 18 items. The reliability and validity of the PSESCAMS were proved.
Angiographic findings after vaginal gauze packing: New insight into an old technique
Authors: Koyama Shinsuke , Maeda Munehiro , Kobayashi Masaki , Tanaka Yusuke , Kubota Satoshi , Nakamura Ryo , Isobe Masanori , Shiki Yasuhiko
Published: April 2013

We had a transferred case of cervical ectopic pregnancy with hemorrhagic shock at 6 weeks of gestation. Upon arrival at hospital, we performed tight and full vaginal gauze packing to push the uterus upward to control the patient's hemorrhage. Following stabilization of her general condition, she was treated with uterine artery embolization. Using angiography, the effectiveness of vaginal gauze packing for emergency hemostasis by the presumed mechanism of impairing blood flow through the uterine artery was demonstrated. To our knowledge, there are no reports that have previously demonstrated angiographic findings similar to ours after vaginal gauze packing. Vaginal gauze packing is an effective, rapid, and convenient hemostatic procedure able to be carried out in a time‐sensitive and challenging situation. As a result, this procedure gives clinicians more time to improve the patients' general status and arrange for transfusion and further definitive treatment.
Women with Deep Infiltrating Endometriosis: Sexual Satisfaction, Desire, Orgasm, and Pelvic Problem Interference with Sex
Authors: Montanari Giulia , Di Donato Nadine , Benfenati Arianna , Giovanardi Giulia , Zannoni Letizia , Vicenzi Claudia , Solfrini Serena , Mignemi Giuseppe , Villa Gioia , Mabrouk Mohamed , Schioppa Claudio , Venturoli Stefano , Seracchioli Renato
Published: April 2013

Introduction

Endometriosis is a chronic and progressive condition of women of reproductive age. It is strongly associated with a significant reduction of quality of life (QOL) and sexual function.

Aims

This study aims to objectively evaluate sexual function in women with deep infiltrating endometriosis (DIE) and to study the impact of endometriosis symptoms and type of lesion on patient's sexual function.

Methods

This is a cross-sectional study in a tertiary care university hospital. It included 182 patients with preoperative clinical and ultrasound diagnosis of DIE who were referred to our center from 2008 to 2011.

Main Outcome Measures

A sexual activity questionnaire, the Sexual Health Outcomes in Women Questionnaire (SHOW-Q) was used to collect data pertaining to satisfaction, orgasm, desire, and pelvic problem interference with sex. Short Form 36 (SF-36) was used to evaluate QOL. Demographic and clinical characteristics were assessed: age, body mass index, parity, ethnicity, postsecondary education, employment, smoking, history of surgical treatment, and hormonal contraception. Patients were asked about pain symptoms (dysmenorrhea, dyspareunia, dyschezia, chronic pelvic pain, and dysuria) using a visual analog scale.

Results

The mean values obtained on the different scales of the SHOW-Q showed poor sexual function (mean SHOW-Q total score 56.38 ± 22.74). Satisfaction was the dimension most affected (mean satisfaction score 55.66 ± 34.55), followed by orgasm (mean orgasm score 56.90 ± 33.77). We found a significant correlation between the SF-36 scores and the SHOW-Q scores (P < 0.0001). Sexual dysfunction and deterioration of QOL seem to be correlated. Analyzing the impact of symptoms and lesions on sexual function, we found that dyspareunia and vaginal DIE nodules significantly affect sexual activity (P < 0.05).

Conclusion

The results of this study demonstrated that women with DIE have a sexual function impairment, correlated with the overall well-being decrease. Moreover, the presence of dyspareunia and vaginal endometriotic lesions seems to be involved in sexual dysfunction.
Effects of Mosquitofish, Gambusia affinis, on Channel Catfish, Ictalurus puncatatus, Production Ponds
Authors: Mischke Charles C. , Griffin Matt J. , Greenway Terrence E. , Wise David
Published: April 2013

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.
Use of Corn Germ Meal in Diets for Pond‐Raised Channel Catfish, Ictalurus punctatus
Authors: Li Menghe H. , Robinson Edwin H. , Oberle Daniel F. , Lucas Penelope M. , Bosworth Brian G.
Published: April 2013

Corn germ meal (CGM) is a by‐product of corn milling. On the basis of its nutrient composition and digestibility values, it appears to be a suitable ingredient for use in channel catfish, Ictalurus punctatus, diets. A study was conducted to examine the use of various levels of CGM in diets for pond‐raised channel catfish. Four 28% protein diets containing 0, 15, 25, and 35% CGM were evaluated. Fingerling channel catfish (mean initial weight: 71 g/fish) were stocked into 24, 0.04‐ha ponds at a rate of 14,826 fish/ha. Fish were fed once daily to apparent satiation for a 167‐d growing season. No significant differences were observed in total amount of diet fed, diet consumption per fish, net yield, weight gain, feed conversion ratio, survival, fillet yield, and fillet protein, fat, and moisture concentrations among fish fed diets containing various levels of CGM. Carcass yield decreased linearly as dietary CGM levels increased. Depending on prices, CGM can be used interchangeably with corn gluten feed in channel catfish diets as replacements for corn, wheat middlings, and soybean meal to reduce feed cost.
Density and Organic Matter Influence on Egg‐laying and Hatching of Branchiura sowerbyi (Oligochaeta)
Authors: Rech Karine Cristiane , Guereschi Renata Maria , de Oliveira Nuñer Alex Pires , Sticca Sarah Carvalho
Published: April 2013

This study aimed to assess the combined effects of density of adults of Branchiura sowerbyi and the source of organic matter on the production of eggs and young species. The experimental units used were 250‐mL beakers with 100 mL of fine sand (0.074–0.210 mm) and 150 mL of chlorine‐free water with constant aeration at the temperature 25 C. The experiment was conducted based on a two‐factor model with six treatments and three repetitions, applied in a completely random design. The densities 5 individuals/38.5cm2 (D5; 1298/m2) and 8 individuals/38.5cm2 (D8; 2078/m2) were assessed with commercial fish feed (FF), commercial poultry feed (PF), and turkey manure (TM) as sources of organic matter. A total of 1223 cocoons and 2138 eggs were produced, with average hatching of 40.0 ± 15.1%. The highest number of cocoons and eggs was found with the use of PF, D8 having produced the highest number of cocoons and eggs. The hatching rate was not influenced by the source of organic matter or density and no influence was registered from the density of adults on the survival. The PF provided the highest growth of adults, and generally the use of TM provided the worst performance.
Systolic and diastolic dysfunction in cirrhosis: a tissue‐Doppler and speckle tracking echocardiography study
Authors: Sampaio Francisco , Pimenta Joana , Bettencourt Nuno , Fontes‐Carvalho Ricardo , Silva Ana P. , Valente João , Bettencourt Paulo , Fraga José , Gama Vasco
Published: April 2013

Background & Aims

Cardiac dysfunction has been described in patients with cirrhosis. Conventional echocardiographic methods are frequently unable to detect abnormalities at rest and have limitations. We aimed to evaluate cardiac function in cirrhosis patients assessing: (i) left ventricular systolic function using speckle‐tracking imaging; (ii) diastolic function using a tissue‐Doppler based algorithm and comparing it with previously proposed definition of diastolic dysfunction (DD).

Methods

We included 109 hospitalized and ambulatory patients with cirrhosis and 18 healthy controls. Detailed echocardiographic evaluation was performed including tissue‐Doppler and speckle‐tracking analysis.

Results

Peak systolic longitudinal strain (PLS) was lower in patients [−19.99% (−21.88 to −18.71) vs −22.02% (−23.10 to −21.18), P = 0.003]. Ejection fraction was similar in patients and controls [64% (59–67) vs 61% (60–65), P = 0.42)]. Based on mitral‐flow pattern, DD was present in 44 patients (40.4%). Patients without DD had higher cardiac output compared with those with DD [6.4 L/min (5.4–7.2) vs 5.6 L/min (4.6–6.8), P = 0.02]. Using a tissue‐Doppler based definition, the prevalence of DD was 16.5%. No differences in haemodynamic variables were found in patients with and without this definition of DD. The agreement between the two definitions of DD was weak (kappa = 0.24, P = 0.003). Echocardiographic abnormalities in systolic and diastolic function were not different in compensated vs decompensated patients in different Child‐Pugh classes or cirrhosis aetiologies.

Conclusions

Patients with cirrhosis have systolic and diastolic cardiac dysfunction at rest. Newer echocardiographic techniques may identify patients with functional impairment more accurately than conventional methods, which are more influenced by flow conditions.
RADseq underestimates diversity and introduces genealogical biases due to nonrandom haplotype sampling
Authors: Arnold B. , Corbett‐Detig R. B. , Hartl D. , Bomblies K.
Published: April 2013

Reduced representation genome‐sequencing approaches based on restriction digestion are enabling large‐scale marker generation and facilitating genomic studies in a wide range of model and nonmodel systems. However, sampling chromosomes based on restriction digestion may introduce a bias in allele frequency estimation due to polymorphisms in restriction sites. To explore the effects of this nonrandom sampling and its sensitivity to different evolutionary parameters, we developed a coalescent‐simulation framework to mimic the biased recovery of chromosomes in restriction‐based short‐read sequencing experiments (RADseq). We analysed simulated DNA sequence datasets and compared known values from simulations with those that would be estimated using a RADseq approach from the same samples. We compare these ‘true’ and ‘estimated’ values of commonly used summary statistics, π, θw, Tajima's D and FST. We show that loci with missing haplotypes have estimated summary statistic values that can deviate dramatically from true values and are also enriched for particular genealogical histories. These biases are sensitive to nonequilibrium demography, such as bottlenecks and population expansion. In silico digests with 102 completely sequenced Drosophila melanogaster genomes yielded results similar to our findings from coalescent simulations. Though the potential of RADseq for marker discovery and trait mapping in nonmodel systems remains undisputed, our results urge caution when applying this technique to make population genetic inferences.
Whither Philosophy?
Authors: Stern Robert
Published: April 2013

This article considers possible future directions of philosophy, based around the experience of the author as editor of the European Journal of Philosophy for about a decade. After some discussion of the original impetus for the journal, and of how the philosophy scene has changed since it was founded in 1993, the article focuses particularly on the themes of transcendentalism and naturalism as likely to shape the philosophical debates of the future, as they have done in the past.
A meta‐analysis of experimental warming effects on terrestrial nitrogen pools and dynamics
Authors: Bai Edith , Li Shanlong , Xu Wenhua , Li Wei , Dai Weiwei , Jiang Ping
Published: April 2013

Global warming may have profound effects on terrestrial ecosystems. However, a comprehensive evaluation of the effects of warming on ecosystem nitrogen (N) pools and dynamics is not available.

Here, we compiled data of 528 observations from 51 papers and carried out a meta‐analysis of experimental warming effects on 13 variables related to terrestrial N pools and dynamics.

We found that, on average, net N mineralization and net nitrification rate were increased by 52.2 and 32.2%, respectively, under experimental warming treatment. N pools were also increased by warming, although the magnitude of this increase was less than that of N fluxes. Soil microbial N and N immobilization were not changed by warming, probably because microbes are limited by carbon sources. Grassland and shrubland/heathland were less responsive to warming than forest, probably because the reduction of soil moisture by warming offset the temperature effect in these areas. Soil heating cable and all‐day treatment appeared to be the most effective method on N cycling among all treatment methods.

Results of this meta‐analysis are useful for better understanding the response of N cycling to global warming and the underlying mechanism of warming effects on plants and ecosystem functions.
RADIOGRAPHIC CHARACTERIZATION OF PRESUMED PLATE‐LIKE ATELECTASIS IN 75 NONANESTHETIZED DOGS AND 15 CATS
Authors: Giglio Robson F. , Winter Matthew D. , Reese David J. , Thrall Donald E. , Abbott Jeffrey R. , Graham John P. , Berry Clifford R.
Published: April 2013

Discrete discoid or linear areas of increased soft opacity have been observed within the pulmonary parenchyma in thoracic radiographs of dogs and cats. Similar radiographic findings have been described in humans and termed plate‐like atelectasis. The purpose of this retrospective study was to describe locations and characteristics of presumed plate‐like atelectasis, presence of concurrent thoracic disease(s), and presence of persistent pulmonary changes on recheck thoracic radiographic studies in a cohort of dogs and cats. Hospital records between 2004 and 2011 were searched and a total of 90 cases were included (75 dogs and 15 cats, 2–17 years of age). Plate‐like atelectasis was most commonly found in left lateral radiographs. Plate‐like atelectasis was observed in the cranial thorax and was oriented in a dorsocranial to ventrocaudal direction in 68 (75%) patients. Plate‐like atelectasis averaged 29.6 ± 14.4 mm in length and 2.6 ± 1.3 mm in width. In 57 of the 90 patients (63%), plate‐like atelectasis was the only abnormality found. Plate‐like atelectasis was present in 7 of 22 cases where follow‐up radiographs were available. Findings from the current study indicated that, while the etiology of plate‐like atelectasis remains unknown, anatomic variations in sublobar pulmonary anatomy might account for pleural areas of atelectasis. The authors propose that the presence of plate‐like atelectasis may represent areas of atelectasis that track along sublobar lung lobe separations, an area of hypoventilation or decreased collateral ventilation, and/or area of decreased localized surfactant deficiency.
Removal of half the sympathetic innervation does not reduce vasoconstrictor responses in rat tail artery
Authors: Tripovic Diana , McLachlan Elspeth M. , Brock James A.
Published: April 2013

Key points

To test whether the responses of the normal rat tail artery to supramaximal nerve stimulation depend on activating all of its innervation, half the sympathetic innervation was surgically removed (partial denervation, PD).

After PD, the amplitude of excitatory junction potentials was halved but the amplitudes of contractions of isolated segments of PD arteries were of normal amplitude.

The effects of α2‐adrenoceptor mediated auto‐inhibition of noradrenaline release and prejunctional re‐uptake of released noradrenaline were not reduced after PD.

The normal contraction amplitude could not be explained by upregulation of junctional or extra‐junctional adrenoceptors after PD, although slightly increased α2‐adrenoceptor sensitivity prolonged contraction duration, amplifying responses during continuous stimulation.

A surprising conclusion is that post‐receptor mechanisms activated by noradrenaline released from sympathetic nerves are normally saturated. If this applies to other arteries, it significantly changes understanding of their control by sympathetic nerves.

Abstract  Following reinnervation of denervated rat tail arteries, nerve‐evoked contractions are at least as large as those evoked in normally innervated arteries despite a much lower nerve terminal density. Here nerve‐evoked contractions have been investigated after transection of half the sympathetic innervation of normal tail arteries. After 1 week, the noradrenergic plexus 50–70 mm along the tail was about half as dense as control. Excitatory junction potentials recorded in smooth muscle cells of arterial segments isolated in vitro were half their normal amplitude. Surprisingly, nerve‐evoked contractions of isometrically mounted segments were not reduced in amplitude, as was also the case after only 3 days. After 1 week, enhancement of nerve‐evoked contractions by blocking either neuronal re‐uptake of noradrenaline with desmethylimipramine or prejunctional α2‐adrenoceptors with idazoxan was similar to control, suggesting that these mechanisms are matched to the number of innervating axons. The relative contribution of postjunctional α2‐adrenoceptors to contractions evoked by long trains of stimuli was enhanced but that of α1‐adrenoceptors was unchanged. Transiently, sensitivity to the α1‐adrenoceptor agonist phenylephrine was slightly increased. After 7 weeks, amplitudes of nerve‐evoked contractions remained similar to control, and sensitivity to phenylephrine had recovered but that to the α2‐adrenoceptor agonist clonidine was slightly raised. The normal amplitude of nerve‐evoked contractions after partial denervation is only partly explained by the greater contribution of α2‐adrenoceptors. While the post‐receptor mechanisms activated by nerve‐released transmitter may be modified to amplify the contractions after partial denervation, our findings suggest that these mechanisms are normally saturated, at least in this artery.
Effects of leucine and its metabolite β‐hydroxy‐β‐methylbutyrate on human skeletal muscle protein metabolism
Authors: Wilkinson D. J. , Hossain T. , Hill D. S. , Phillips B. E. , Crossland H. , Williams J. , Loughna P. , Churchward‐Venne T. A. , Breen L. , Phillips S. M. , Etheridge T. , Rathmacher J. A. , Smith K. , Szewczyk N. J. , Atherton P. J.
Published: April 2013

Key points

The branched‐chain amino acid (BCAA) leucine acts as both a ‘trigger’ for the initiation of protein synthesis, and as a substrate for newly synthesized protein.

As a BCAA, leucine can be metabolized within skeletal muscle, leaving open the possibility that leucine metabolites might possess anabolic properties.

One metabolite in particular, β‐hydroxy‐β‐methylbutyrate (HMB), has shown positive effects on lean body mass and strength following exercise, and in disease‐related muscle wasting, yet its impact on acute human muscle protein turnover is undefined.

We report here that HMB stimulates muscle protein synthesis to a similar extent to leucine. HMB was also found to decrease muscle protein breakdown.

Our observation that HMB enhances muscle protein anabolism may partly (or wholly) underlie its pre‐defined anabolic/anti‐catabolic supplemental efficacy in humans.

Abstract  Maintenance of skeletal muscle mass is contingent upon the dynamic equilibrium (fasted losses–fed gains) in protein turnover. Of all nutrients, the single amino acid leucine (Leu) possesses the most marked anabolic characteristics in acting as a trigger element for the initiation of protein synthesis. While the mechanisms by which Leu is ‘sensed’ have been the subject of great scrutiny, as a branched‐chain amino acid, Leu can be catabolized within muscle, thus posing the possibility that metabolites of Leu could be involved in mediating the anabolic effect(s) of Leu. Our objective was to measure muscle protein anabolism in response to Leu and its metabolite HMB. Using [1,2‐13C2]Leu and [2H5]phenylalanine tracers, and GC‐MS/GC‐C‐IRMS we studied the effect of HMB or Leu alone on MPS (by tracer incorporation into myofibrils), and for HMB we also measured muscle proteolysis (by arteriovenous (A–V) dilution). Orally consumed 3.42 g free‐acid (FA‐HMB) HMB (providing 2.42 g of pure HMB) exhibited rapid bioavailability in plasma and muscle and, similarly to 3.42 g Leu, stimulated muscle protein synthesis (MPS; HMB +70%vs. Leu +110%). While HMB and Leu both increased anabolic signalling (mechanistic target of rapamycin; mTOR), this was more pronounced with Leu (i.e. p70S6K1 signalling ≤90 min vs. ≤30 min for HMB). HMB consumption also attenuated muscle protein breakdown (MPB; −57%) in an insulin‐independent manner. We conclude that exogenous HMB induces acute muscle anabolism (increased MPS and reduced MPB) albeit perhaps via distinct, and/or additional mechanism(s) to Leu.
Concurrent Design of Product Families and Reconfigurable Assembly Systems
Authors: Bryan April , Wang Hui , Abell Jeffrey
Published: April 2013

To cope with the challenges of market competition and the greater purchasing power of consumers, manufacturers have increased the variety of products they offer. Product families and reconfigurable manufacturing systems (RMS) are used to produce product variety cost-effectively. However, there is a lack of concurrent engineering methods for the joint design of a product family and an RMS, since existing concurrent engineering methods were developed for a single product and its associated manufacturing system. The presence of product variety brings challenges to the concurrent engineering of a product family and its reconfigurable assembly system (RAS), as the decision space is broader. This paper introduces a mathematical model for the concurrent design of a product family and a RAS. In addition, a mathematical model for the sequential approach to product family and RAS design is introduced to compare with the results of the concurrent methodology. A genetic algorithm has been developed to solve the models introduced for both the concurrent and sequential approaches. Examples are used to demonstrate the implementation of the concurrent approach to product family and RAS design and the benefits that could be achieved by using this approach. The solutions indicate that the concurrent design of product families and RASs leads to profits that are the same as or higher than the profits obtained with the sequential design approach. Therefore, the concurrent design of product families and RAS methodology is a more cost-effective approach to designing families of products and their associated manufacturing systems.
Estimation of fast and slow wave properties in cancellous bone using Prony's method and curve fitting
Authors: Wear Keith A.
Published: April 2013

The presence of two longitudinal waves in poroelastic media is predicted by Biot's theory and has been confirmed experimentally in through-transmission measurements in cancellous bone. Estimation of attenuation coefficients and velocities of the two waves is challenging when the two waves overlap in time. The modified least squares Prony's (MLSP) method in conjuction with curve-fitting (MLSP + CF) is tested using simulations based on published values for fast and slow wave attenuation coefficients and velocities in cancellous bone from several studies in bovine femur, human femur, and human calcaneus. The search algorithm is accelerated by exploiting correlations among search parameters. The performance of the algorithm is evaluated as a function of signal-to-noise ratio (SNR). For a typical experimental SNR (40 dB), the root-mean-square errors (RMSEs) for one example (human femur) with fast and slow waves separated by approximately half of a pulse duration were 1 m/s (slow wave velocity), 4 m/s (fast wave velocity), 0.4 dB/cm MHz (slow wave attenuation slope), and 1.7 dB/cm MHz (fast wave attenuation slope). The MLSP + CF method is fast (requiring less than 2 s at SNR = 40 dB on a consumer-grade notebook computer) and is flexible with respect to the functional form of the parametric model for the transmission coefficient. The MLSP + CF method provides sufficient accuracy and precision for many applications such that experimental error is a greater limiting factor than estimation error.
Development of a hybrid wave based–transfer matrix model for sound transmission analysis
Authors: Dijckmans A. , Vermeir G.
Published: April 2013

In this paper, a hybrid wave based–transfer matrix model is presented that allows for the investigation of the sound transmission through finite multilayered structures placed between two reverberant rooms. The multilayered structure may consist of an arbitrary configuration of fluid, elastic, or poro-elastic layers. The field variables (structural displacements and sound pressures) are expanded in terms of structural and acoustic wave functions. The boundary and continuity conditions in the rooms determine the participation factors in the pressure expansions. The displacement of the multilayered structure is determined by the mechanical impedance matrix, which gives a relation between the pressures and transverse displacements at both sides of the structure. The elements of this matrix are calculated with the transfer matrix method. First, the hybrid model is numerically validated. Next a comparison is made with sound transmission loss measurements of a hollow brick wall and a sandwich panel. Finally, numerical simulations show the influence of structural damping, room dimensions and plate dimensions on the sound transmission loss of multilayered structures.
The time course of perception of coarticulation
Authors: Beddor Patrice Speeter , McGowan Kevin B. , Boland Julie E. , Coetzee Andries W. , Brasher Anthony
Published: April 2013

The perception of coarticulated speech as it unfolds over time was investigated by monitoring eye movements of participants as they listened to words with oral vowels or with late or early onset of anticipatory vowel nasalization. When listeners heard [CṼNC] and had visual choices of images of CVNC (e.g., send) and CVC (said) words, they fixated more quickly and more often on the CVNC image when onset of nasalization began early in the vowel compared to when the coarticulatory information occurred later. Moreover, when a standard eye movement programming delay is factored in, fixations on the CVNC image began to occur before listeners heard the nasal consonant. Listeners' attention to coarticulatory cues for velum lowering was selective in two respects: (a) listeners assigned greater perceptual weight to coarticulatory information in phonetic contexts in which [Ṽ] but not N is an especially robust property, and (b) individual listeners differed in their perceptual weights. Overall, the time course of perception of velum lowering in American English indicates that the dynamics of perception parallel the dynamics of the gestural information encoded in the acoustic signal. In real-time processing, listeners closely track unfolding coarticulatory information in ways that speed lexical activation.
An acoustic inverse scattering problem for spheres with radially inhomogeneous compressibility
Authors: Bilgin Egemen , Yapar Ali , Yelkenci Tanju
Published: April 2013

An inverse acoustic scattering problem the main aim of which is to reconstruct the one-dimensional variation of the acoustical parameters of a spherical object is investigated. The problem is first formulated conventionally through a coupled system of integral equations, and then this system is reduced to one-dimensional form by using the orthogonality properties of spherical harmonics. The inverse problem is solved in an iterative fashion via classical Newton algorithm. Some numerical simulations are carried out to test the feasibility of the method as well as to see the effects of some parameters on the solution. It is shown that the method is very effective for the profiles having smooth variations provided that an appropriate initial guess is chosen. However, some of the classical disadvantages of the Newton type algorithms are also observed in numerical experiments which may limit the applicability of the method to a certain extent.
Sound scattering by a vortex dipole
Authors: Naugolnykh Konstantin
Published: April 2013

Sound scattering by a system of two counter-rotating vortices (Lamb dipole) is considered, using the effective approach of Pitaevskii [J. Exp. Theor. Phys (USSR) 35, 1271–1275 (1958); Sov. Phys. JETP 85, 888–890 (1959)], based on application of the asymptotic representation of the scattering Green function, the Dirac delta function modeling of the vortex, and the Fourier transformation of the vector of scattering. The sound frequency is supposed to be low. The directivity pattern of the radiation, scattered by the Lamb dipole is obtained. There is no singularity in scattering field in this case as it must be for the vorticity with zero circulation, so the dipole is a more appropriate object for the approximation used.