bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographical delimitation of a partial selective sweep in African Drosophila melanogaster
Authors: Frezal L. , Meli F. , Mousset S. , Mona S. , Veuille M.
Published: October 2012

Positive selection leaves characteristic footprints on DNA variation but detecting such patterns is challenging as the age, the intensity and the mode of selection as well as demography and evolutionary parameters (mutation and recombination rates) all play roles and these are difficult to disentangle. We recorded nucleotide variation in a sample of isogenic chromosomes from a western African population of Drosophila melanogaster at a locus (Fbp2) for which a partial selective sweep had previously been reported. We compared this locus to four other genes from the same chromosomes and from a European and an East African population. Then, we assessed Fbp2 variation in a sample of 370 chromosomes covering a comprehensive geographic sampling of 16 African localities. The signature of selection was tested while accounting for the demographic history of the populations. We found a significant signal of selection in two West African localities including Ivory Coast. Variation at Fpb2 would thus represent a case of an ongoing selective sweep in the range of this species. A weaker, nonsignificant, signal of selection was, however, apparent in some other populations, thus leaving open several possibilities: (i) the selective sweep originated in Ivory Coast and has spread to the rest of the continent; (ii) several African populations report the signature of a selective event having occurred in an ancestral population; (iii) this genome region is subject to independent selective events in African populations; and (iv) A neutral scenario with population subdivision and local bottleneck cannot be fully excluded to explain the molecular patterns observed in some populations.
QST < FSTAs a signature of canalization
Authors: Lamy Jean‐Baptiste , Plomion Christophe , Kremer Antoine , Delzon Sylvain
Published: October 2012

A key aim of evolutionary biology – inferring the action of natural selection on wild species – can be achieved by comparing neutral genetic differentiation between populations (FST) with quantitative genetic variation (QST). Each of the three possible outcomes of comparisons ofQSTandFST(QST > FST,QST = FST,QST < FST) is associated with an inference (diversifying selection, genetic drift, uniform selection, respectively). However, published empirical and theoretical studies have focused on theQST > FSToutcome. We believe that this reflects the absence of a straightforward biological interpretation of theQST < FSTpattern. We here report recent evidence of this neglected evolutionary pattern, provide guidelines to its interpretation as either a canalization phenomenon or a consequence of uniform selection and discuss the significant importance this issue will have for the area of evolutionary biology.
The proteomics of feather development in pied flycatchers (Ficedula hypoleuca) with different plumage coloration
Authors: Leskinen Paula K. , Laaksonen Toni , Ruuskanen Suvi , Primmer Craig R. , Leder Erica H.
Published: October 2012

The genetic theory of morphological evolution postulates that form evolves largely by changing the expression proteins that are functionally conserved. It follows that understanding the function of proteins during different phases of development as well as the mechanisms by which the functions are modified is a prerequisite for understanding evolutionary change. Male pied flycatchers exhibit marked phenotypic variation in their breeding plumage. This variation has repeatedly been shown to have adaptive significance, but the molecular basis of this variation is not known. Here, we characterize the proteome of developing pied flycatcher feathers from differently pigmented males and also introduce a new method for examining the effect sizes of expression differences in protein interaction networks. Approximately 300 proteins were identified in the developing feathers of males. Gene products associated with cellular transport, cell metabolism and protein synthesis formed a large part of the developing feather proteome. Sixty‐five proteins associated with the development of the epidermis and/or pigmentation were detected in the data. The examination of expression level differences of protein–protein interaction networks revealed an immunological signalling–related network to exhibit significantly higher expression in black compared to brown males. Additionally, indications of differences in energy balance and oxidative stress related characteristics were detected. Together, these results provide new insight into the molecular mechanisms and evolutionary significance of plumage colour variation.
Inferences on population history of a seed chalcid wasp: invasion success despite a severe founder effect from an unexpected source population
Authors: Auger‐Rozenberg M.‐A. , Boivin T. , Magnoux E. , Courtin C. , Roques A. , Kerdelhué C.
Published: October 2012

Most invasive species established inEurope originate from eitherAsia orNorthAmerica, but little is currently known about the potential of theAnatolianPeninsula (AsiaMinor) and/or theNearEast to constitute invasion sources. Mediterranean forests are generally fragile ecosystems that can be threatened by invasive organisms coming from different regions of theMediterraneanBasin, but for which historical data are difficult to gather and the phylogeographic patterns are still poorly understood for most terrestrial organisms. In this study, we characterized the genetic structure ofMegastigmus schimitscheki, an invasive seed‐feeding insect species originating from the Near East, and elucidated its invasion route inSouth‐easternFrance in the mid 1990s. To disentangle the evolutionary history of this introduction, we gathered samples from the main native regions (TaurusMountains inTurkey,Lebanon andCyprus) and from the invaded region that we genotyped using five microsatellite markers and for which we sequenced the mitochondrialCytochromeOxidaseIgene. We applied a set of population genetic statistics and methods, including approximate Bayesian computation. We proposed a detailed phylogeographic pattern for theNearEast populations, and we unambiguously showed that the French invasive populations originated fromCyprus, although the available historical data strongly suggested thatTurkey could be the most plausible source area. Interestingly, we could show that the introduced populations were founded from an extremely restricted number of individuals that realized a host switch fromCedrus brevifoliatoC. atlantica. Evolutionary hypotheses are discussed to account for this unlikely scenario.
Enteric‐coated mycophenolate sodium in combination with full dose or reduced dose cyclosporine, basiliximab and corticosteroids in Australian de novo kidney transplant patients
Authors: Chadban Steve , Eris Josette , Russ Graeme , Campbell Scott , Chapman Jeremy , Pussell Bruce , Trevillian Paul , Ierino Francesco , Thomson Napier , Hutchison Brian , Irish Ashley , Woodcock Chad , Kurstjens Nicol , Walker Rowan ,   the MyProms AU01 Study Group
Published: October 2012

This RCT examined whether enteric‐coated mycophenolate sodium would enable use of CsA dosed to reduced C2 targets. There was no significant difference in creatinine clearance, AR, graft loss or death for usual versus reduced exposure CsA suggesting de novo renal transplant patients can safely receive a regimen of either full or reduced exposure CsA with EC‐MPS, corticosteroids and basiliximab.
The earliest records of internally stratified cyanobacterial and algal lichens from the Lower Devonian of the Welsh Borderland
Authors: Honegger Rosmarie , Edwards Dianne , Axe Lindsey
Published: October 2012

Lichenization is assumed to be a very ancient mode of fungal nutrition, but fossil records are rare. Here we describe two fragments of exceptionally preserved, probably charred, lichen thalli with internal stratification.Cyanolichenomycites devonicushas a cyanobacterial andChlorolichenomycites salopensisa unicellular, presumably green algal photobiont. Fruiting bodies are missing.Cyanolichenomycites devonicusforms asexual spores in a pycnidium.

All specimens were examined with scanning electron microscopy techniques. The fossils were extracted by maceration. Extant lichens and free‐living cyanobacteria were either experimentally charcoalified for comparison or conventionally prepared.

Based on their septate hyphal structure, both specimens are tentatively interpreted as representatives of the Pezizomycotina (Ascomycota). Their presence in 415 million yr (Myr) old rocks from the Welsh Borderland predates existing Late Cretaceous records of pycnidial conidiomata by some 325 Myr and Triassic records of lichens with broadly similar organization by some 195 Myr.

These fossils represent the oldest known record of lichens with symbionts and anatomy as typically found in morphologically advanced taxa today. The latter does not apply toWinfrenatia reticulata, the enigmatic crustose lichen fossil from the Lower Devonian, nor to presumed lichen‐like organisms such as the CambrianFarghera robustaor to the Lower DevonianSpongiophyton minutissimum.
Surfactant lavage therapy for respiratory deterioration in extremely premature infants
Authors: Iwatani Sota , Mizobuchi Masami , Tanaka Satoshi , Inomata Kei , Sakai Hitomi , Yoshimoto Seiji , Nakao Hideto
Published: October 2012

The following article from Pediatrics International, ‘Surfactant lavage therapy for respiratory deterioration in extremely premature infants’ by Sota Iwatani, Masami Mizobuchi, Satoshi Tanaka, Kei Inomata, Hitomi Sakai, Seiji Yoshimoto and Hideto Nakao, posted online as an Accepted Article on 30 October 2012 in Wiley Online Library (wileyonlinelibrary.com), has been withdrawn by agreement between the authors, the journal Editor in Chief, and Wiley Publishing Asia Pty. Ltd. The withdrawal has been agreed due to deficiencies in the study design.

Reference

Sota Iwatani, Masami Mizobuchi, Satoshi Tanaka, Kei Inomata, Hitomi Sakai, Seiji Yoshimoto and Hideto Nakao

Accepted manuscript online: 30 OCT 2012

DOI: 10.1111/ped.12003
Factors affecting exclusive breast‐feeding during the first 6 months in Korea
Authors: Kim Myo Jing , Kim Yu‐Mi , Yoo Jae‐Ho
Published: October 2012

Background

The aim of this study was to identify the status of exclusive breast‐feeding (EBF) in Korea and analyze the factors affecting exclusive breast‐feeding at 6 months of age.

Method

This study was based on data obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) IV, conducted from January 2007 to December 2008. A total of 404 mother–infant pairs were recruited. Exclusive breast‐feeding was defined according to the criteria established by the World Health Organization.

Result

The rate of EBF was 60.9% for 1 month, 55.0% for 3 months, 35.4% for 6 months, 3.7% for 9 months and 1.2% for 12 months after birth. According to a stepwise logistic regression analysis, factors that were positively associated with EBF at 6 months were younger maternal age (odds ratio [OR] = 0.85, 95% confidence interval [CI]: 0.79–0.92), higher maternal education level (OR = 2.29, 95%CI: 1.17–4.46) and living in a capital city (OR = 2.64, 95%CI: 1.46–4.75).

Conclusion

The rate of EBF in Korea is still suboptimal. To promote EBF, persistent and systematic education and campaigns for breast‐feeding should be provided, particularly in vulnerable regions.
Factors Affecting the First Service Conception Rate of Cows in Smallholder Dairy Farms in Bangladesh
Authors: Siddiqui MAR , Das ZC , Bhattacharjee J , Rahman MM , Islam MM , Haque MA , Parrish JJ , Shamsuddin M
Published: October 2012

Contents

The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows.
Effects of a plastic cover on soil moisture change in a Mediterranean climatic regime
Authors: Díaz‐Hernández J. L. , Salmerón T.
Published: October 2012

Water deficit is a serious problem for most agricultural crops, especially in arid–semiarid regions, and limits sustainable development. Production can be improved by reducing evapotranspiration and loss of infiltrated water by the use of a plastic cover. We monitored soil moisture fortnightly over 1 yr using a neutron probe near four trees in an olive grove (Olea europaea, var. Arbequina), two of which had a plastic cover buried in the topsoil around them. These trees were monitored using three neutron probe access tubes per tree to compare the behaviour of soil moisture over time with two other identically instrumented and nearby trees with no cover. Analysis was based on the resultant moisture profiles. The plastic cover retained moisture and increased soil water residence time. During the dry season, the amount of water retained in the plots was at most 15–20% greater in the mid‐season and at least 5–6% greater at the end of season than in the central part of the plots near the trunk. The plastic cover was effective to ca. 50 cm with maximum water content near the soil surface. During the wet season, the cover did not affect soil water. Soil moisture was greater near the tree trunk as a result of stemflow and throughfall.
Myocardial scars correlate with eletrocardiographic changes in chronic Trypanosoma cruzi infection for dogs treated with Benznidazole
Authors: Caldas Ivo Santana , da Matta Guedes Paulo Marcos , dos Santos Fabiane Matos , de Figueiredo Diniz Lívia , Martins Tassiane Assíria Fontes , da Silva do Nascimento Alvaro Fernando , Azevedo Maira Araújo , de Lima Wanderson Geraldo , Neto Raimundo Marques Nascimento , Torres Rosália Morais , Talvani André , Bahia Maria Terezinha
Published: October 2012

Objectives  The cardiac form of Chagas disease is evidenced by a progressive cardiac inflammation that leads to myocarditis, fibrosis and electrocardiographic (ECG) conduction abnormalities. Considering these characteristics, the aim of this study was to prospectively evaluate the early ECG changes in dogs that were experimentally inoculated with Benznidazole (Bz)‐susceptibly (Berenice‐78) and Bz‐resistant (VL‐10, and AAS) Trypanosoma cruzi strains and, later, evaluate the efficacy of Bz treatment for preventing these ECG alterations.

Methods  Electrocardiographic changes of treated and untreated animals were prospectively evaluated for up to 270 days after infection, at which point collagen (right atrium) quantification was performed.

Results  All infected dogs had a high intensity of heart fibrosis (4616.00 ± 1715.82 collagen/74931 μm2 in dogs infected with Berenice‐78 strain, 5839.2 ± 1423.49 collagen/74931 μm2 in infected by AAS and 6294.40 ± 896.04 collagen/74931 μm2 in animals infected with VL‐10 strain), while 78.57% of all infected dogs showed ECG alterations. Bz Therapy reduced or prevented fibrosis in Bz‐susceptible Berenice‐78 (2813.00 ± 607.13 collagen/74931 μm2) and Bz‐resistant AAS strains (4024 ± 1272.44 collagen/74931 μm2), coincident with only 10% de ECG alterations at 270 days. However, in those animals infected with a Bz‐resistant VL‐10 strain, specific treatment did not alter collagen deposition (6749.5 ± 1596.35 collagen/74931 μm2) and there was first atrioventricular block and chamber overload at 120 and 270 days after infection, with 75% abnormal ECG exams.

Conclusions  These findings indicate that an effective antiparasitic treatment in the early stage of Chagas disease can lead to a significant reduction in the frequency and severity of the parasite‐induced cardiac disease, even if parasites are not completely eliminated.
Emergence of a new focus of Plasmodium malariae in forest villages of district Balaghat, Central India: implications for the diagnosis of malaria and its control
Authors: Bharti Praveen K. , Chand Sunil K. , Singh Mrigendra P. , Mishra Sweta , Shukla Man M. , Singh Rajesh , Singh Neeru
Published: October 2012

Objective  During an epidemiological study (January–July 2012) on malaria in forest villages of Central India, Plasmodium malariae‐like malaria parasites were observed in blood smears of fever cases. We aimed to confirm the presence of P. malariae using molecular tools i.e. species‐specific nested polymerase chain reaction (PCR) and DNA sequencing.

Methods  All fever cases or cases with history of fever in 25 villages of Balaghat district were screened for malaria parasite using bivalent rapid diagnostic test and microscopy after obtaining written informed consent. Nested PCR was employed on microscopically suspected P. malariae cases. DNA sequences in the target region for PCR diagnosis were analysed for all the suspected cases of P. malariae.

Results  Among the 22 microscopy suspected P. malariae cases, nested PCR confirmed the identity of P. malariae in 19 cases. Among these 14 were mono P. malariae infections, three were mixed infection of P. malariae with Plasmodium falciparum and two were mixed infection of P. malariae with Plasmodium vivax. Clinically P. malariae subjects generally presented with fever and headache. However, the typical 3‐day pattern of quantum malaria was not observed. The parasite density of P. malariae was significantly lower than that of P. vivax and P. falciparum.

Discussions  Plasmodium malariae may have been in existence in forest villages of central India but escaped identification due to its close resemblance to P. vivax. The results re‐affirm the importance of molecular methods of testing on routine basis for efficacious control strategies against malaria.
Nutritional supplementation: the additional costs of managing children infected with HIV in resource‐constrained settings
Authors: Cobb G. , Bland R. M.
Published: October 2012

Objective

To explore the financial implications of applying the WHO guidelines for the nutritional management of HIV‐infected children in a rural South African HIV programme.

Methods

WHO guidelines describe Nutritional Care Plans (NCPs) for three categories of HIV‐infected children: NCP‐A: growing adequately; NCP‐B: weight‐for‐age z‐score (WAZ) ≤−2 but no evidence of severe acute malnutrition (SAM), confirmed weight loss/growth curve flattening, or condition with increased nutritional needs (e.g. tuberculosis); NCP‐C: SAM. In resource‐constrained settings, children requiring NCP‐B or NCP‐C usually need supplementation to achieve the additional energy recommendation. We estimated the proportion of children initiating antiretroviral treatment (ART) in the Hlabisa HIV Programme who would have been eligible for supplementation in 2010. The cost of supplying 26‐weeks supplementation as a proportion of the cost of supplying ART to the same group was calculated.

Results

A total of 251 children aged 6 months to 14 years initiated ART. Eighty‐eight required 6‐month NCP‐B, including 41 with a WAZ ≤−2 (no evidence of SAM) and 47 with a WAZ >−2 with co‐existent morbidities including tuberculosis. Additionally, 25 children had SAM and required 10‐weeks NCP‐C followed by 16‐weeks NCP‐B. Thus, 113 of 251 (45%) children were eligible for nutritional supplementation at an estimated overall cost of $11 136, using 2010 exchange rates. These costs are an estimated additional 11.6% to that of supplying 26‐week ART to the 251 children initiated.

Conclusions

It is essential to address nutritional needs of HIV‐infected children to optimise their health outcomes. Nutritional supplementation should be integral to, and budgeted for, in HIV programmes.
Relative benefits of on‐plot water supply over other ‘improved’ sources in rural Vietnam
Authors: Brown Joe , Hien Vo Thi , McMahan Lanakila , Jenkins Marion W. , Thie Lauren , Liang Kaida , Printy Erin , Sobsey Mark D.
Published: October 2012

Objective

Access to improved water sources is rapidly expanding in rural centralVietnam. We examined oneNGO‐led piped water supply programme to assess the drinking water quality and health impacts of piped water systems where access to ‘improved’ water sources is already good.

Methods

This longitudinal, prospective cohort study followed 300 households in seven project areas inDaNang province,Vietnam: 224 households who paid for an on‐plot piped water connection and 76 control households from the same areas relying primarily on ‘improved’ water sources outside the home. The 4‐month study was intended to measure the impact of theNGO‐led water programmes on households' drinking water quality and health and to evaluate system performance.

Results

We found that: (i) households connected to a piped water supply had consistently better drinking water quality than those relying on other sources, including ‘improved’ sources and (ii) connected households experienced less diarrhoea than households without a piped water connection (adjusted longitudinal prevalence ratio: 0.57 (95%CI0.39–0.86,P = 0.006) and households using an ‘improved’ source not piped to the plot: (adjusted longitudinal prevalence ratio: 0.59 (95%CI0.39–0.91,P = 0.018).

Conclusions

Our results suggest that on‐plot water service yields benefits over other sources that are considered ‘improved’ by theWHO/UNICEFJoint Monitoring Programme.
Impact of Severe Temperature Distortion on Turbine Efficiency
Authors: Beard Paul F. , Smith Andy , Povey Thomas
Published: October 2012

This paper presents an experimental and computational study of the effect of severe inlet temperature distortion (hot streaks) on the efficiency of the MT1 HP turbine, which is a highly-loaded unshrouded transonic design. The experiments were performed in the Oxford Turbine Research Facility (OTRF) (formerly the TTF at QinetiQ Farnborough): an engine scale, short duration, rotating transonic facility, in which M, Re, Tgas/Twall and N/T01 are matched to engine conditions. The research formed part of the EU Turbine Aero-Thermal External Flows (TATEF II) program. An advanced second generation temperature distortion simulator was developed for this investigation, which allows both radial and circumferential temperature profiles to be simulated. A pronounced profile was used for this study. The system was novel in that it was designed to be compatible with an efficiency measurement system which was also developed for this study. To achieve low uncertainty (bias and precision errors of approximately 1.5% and 0.2% respectively, to 95% confidence), the mass flow rate of the hot and cold streams used to simulate temperature distortion were independently metered upstream of the turbine nozzle using traceable measurement techniques. Turbine power was measured directly with an accurate torque transducer. The efficiency of the test turbine was evaluated experimentally for a uniform inlet temperature condition, and with pronounced temperature distortion. Mechanisms for observed changes in the turbine exit flow field and efficiency are discussed. The data are compared in terms of flow structure to full stage computational fluid dynamics (CFD) performed using the Rolls Royce Hydra code.
Use of an Immersed Mesh for High Resolution Modeling of Film Cooling Flows
Authors: Lad B. , He L.
Published: October 2012

The development of a high pressure turbine requires the accurate prediction of flow within and around film cooling holes. However, the length scales inherent to film cooling flows produce a large disparity against those of the mainstream flow; hence they cannot be resolved by a mesh generated for an aerodynamics analysis. Furthermore, the process of meshing cooling holes is not only time consuming but cumbersome; thus making the parametric study of film cooling effectiveness for a given blade geometry, using hole geometry and distribution, very difficult in a design environment. In this paper an immersed mesh block (IMB) approach is proposed which allows the refined mesh of a cooling hole to be immersed into the coarser mesh of a nozzle guide vane (NGV) and solved simultaneously while maintaining mass conservation. By employing two-way coupling, the flow physics in and around cooling holes is able to interact with the mainstream; hence the length scales of both types of flow are appropriately resolved. A generic cooling hole design can then be mapped to a given aerofoil geometry multiple times to achieve an appropriate distribution of cooling holes. The results show that for a realistic transonic blade, a configuration consisting of up to 200 cooling holes can be efficiently and accurately calculated—while retaining the original aerodynamic mesh but with a much enhanced resolution for the film cooling.
Shock Propagation and MPT Noise From a Transonic Rotor in Nonuniform Flow
Authors: Defoe Jeffrey J. , Spakovszky Zoltán S.
Published: October 2012

One of the major challenges in high-speed fan stages used in compact, embedded propulsion systems is inlet distortion noise. A body-force-based approach for the prediction of multiple-pure-tone (MPT) noise was previously introduced and validated. In this paper, it is employed with the objective of quantifying the effects of nonuniform flow on the generation and propagation of MPT noise. First-of-their-kind back-to-back coupled aero-acoustic computations were carried out using the new approach for conventional and serpentine inlets. Both inlets delivered flow to the same NASA/GE R4 fan rotor at equal corrected mass flow rates. Although the source strength at the fan is increased by 38 dB in sound power level due to the nonuniform inflow, far-field noise for the serpentine inlet duct is increased on average by only 3.1 dBA overall sound pressure level in the forward arc. This is due to the redistribution of acoustic energy to frequencies below 11 times the shaft frequency and the apparent cut-off of tones at higher frequencies including blade-passing tones. The circumferential extent of the inlet swirl distortion at the fan was found to be two blade pitches, or 1/11th of the circumference, suggesting a relationship between the circumferential extent of the inlet distortion and the apparent cut-off frequency perceived in the far field. A first-principles-based model of the generation of shock waves from a transonic rotor in nonuniform flow showed that the effects of nonuniform flow on acoustic wave propagation, which cannot be captured by the simplified model, are more dominant than those of inlet flow distortion on source noise. It demonstrated that nonlinear, coupled aerodynamic and aero-acoustic computations, such as those presented in this paper, are necessary to assess the propagation through nonuniform mean flow. A parametric study of serpentine inlet designs is underway to quantify these propagation effects.
Prediction of Turbomachinery Aeroelastic Behavior From a Set of Representative Modes
Authors: Mayorca María A. , Vogt Damian M. , Mårtensson Hans , Fransson Torsten H.
Published: October 2012

A method is proposed for the determination of the aeroelastic behavior of a system responding to mode-shapes which are different from the tuned in vacuo ones, due to mistuning, mode family interaction, or any other source of mode-shape perturbation. The method is based on the generation of a data base of unsteady aerodynamic forces arising from the motion of arbitrary modes and uses least square approximations for the prediction of any responding mode. The use of a reduced order technique allows for mistuning analyses and is also applied for the selection of a limited number of arbitrary modes. The application of this method on a transonic compressor blade shows that the method captures the aeroelastic properties well in a wide frequency range. A discussion of the influence of the mode-shapes and frequency on the final stability response is also provided.
Effect of Noise on Generalized Synchronization: An Experimental Perspective
Authors: Ray Anirban , RoyChowdhury A. , Basak Sankar
Published: October 2012

Generalized synchronization between two different nonlinear systems under influence of noise is studied with the help of an electronic circuit and numerical experiment. In the present case, we have studied the phenomena of generalized synchronization between the Lorenz system and another nonlinear system (modified Lorenz) proposed in Ray et al. (2011, “On the Study of Chaotic Systems With Non-Horseshoe Template,” Frontier in the Study of Chaotic Dynamical Systems With Open Problems, Vol. 16, E. Zeraoulia and J. C. Sprott, eds., World Scientific, Singapore, pp. 85–103) from the perspective of electronic circuits and corresponding data collected digitally. Variations of the synchronization threshold with coupling (between driver and driven system) and noise intensity have been studied in detail. Later, experimental results are also proved numerically. It is shown that in certain cases, noise enhances generalized synchronization, and in another it destroys generalized synchronization. Numerical studies in the latter part have also proved results obtained experimentally.
Simulation of Natural Pisa Clay Using an Enhanced Anisotropic Elastoplastic Bounding Surface Model
Authors: Jiang Jianhong , Ling Hoe I. , Kaliakin Victor N.
Published: October 2012

The experimental behavior of natural Pisa clay under complex stress paths is simulated by an enhanced anisotropic elastoplastic bounding surface model. In its present application, the model has nine parameters and focuses on the basic features of clay behavior, such as yielding, critical state, overconsolidation and plastic anisotropy. The model is first calibrated against the test results obtained from tri-axial compression tests and subsequently used to predict the behavior of true tri-axial tests. The overall agreement between the model predictions and the experimental data is very good for proportional loading tests in both meridional and deviatoric stress spaces. The result of prediction is also compared with the original simulations that were conducted by an advanced clay model.
Heat Transfer in a Liquid Film Due to an Unsteady Stretching Surface With Variable Heat Flux
Authors: Liu I.-Chung , Megahed Ahmed M. , Wang Hung-Hsun
Published: October 2012

The heat transfer characteristics of a viscous liquid film flow over an unsteady stretching sheet subject to variable heat flux are investigated numerically. The effect of thermal radiation applying to an optically thick medium is also considered. The governing boundary layer equations are transformed into a set of nonlinear ordinary differential equations using an efficient fifth-order step-adapted Runge–Kutta integration scheme together with Newton–Raphson method. The dimensionless temperature is plotted for various governing parameters; say, unsteadiness parameter, effective Prandtl number, distance index, as well as time index. It is found that the heat transfer aspects are strongly influenced by the relevant parameters.
Energy Harvesting Dynamic Vibration Absorbers
Authors: Ali Shaikh Faruque , Adhikari Sondipon
Published: October 2012

Energy harvesting is a promise to harvest unwanted vibrations from a host structure. Similarly, a dynamic vibration absorber is proved to be a very simple and effective vibration suppression device, with many practical implementations in civil and mechanical engineering. This paper analyzes the prospect of using a vibration absorber for possible energy harvesting. To achieve this goal, a vibration absorber is supplemented with a piezoelectric stack for both vibration confinement and energy harvesting. It is assumed that the original structure is sensitive to vibrations and that the absorber is the element where the vibration energy is confined, which in turn is harvested by means of a piezoelectric stack. The primary goal is to control the vibration of the host structure and the secondary goal is to harvest energy out of the dynamic vibration absorber at the same time. Approximate fixed-point theory is used to find a closed form expression for optimal frequency ratio of the vibration absorber. The changes in the optimal parameters of the vibration absorber due to the addition of the energy harvesting electrical circuit are derived. It is shown that with a proper choice of harvester parameters a broadband energy harvesting can be obtained combined with vibration reduction in the primary structure.
Three-Dimensional Piezoelectricity Solutions for Uniformly Loaded Circular Plates of Functionally Graded Piezoelectric Materials With Transverse Isotropy
Authors: Li X.-Y. , Ding H.-J. , Chen W.-Q. , Li P.-D.
Published: October 2012

This paper considers the bending of a uniformly loaded transversely isotropic piezoelectric circular plate with material properties being arbitrary functions of the thickness coordinate. The displacements and electric potential are expressed in terms of appropriate polynomials of r, the radial coordinate, with coefficients being undetermined functions of z, the axial coordinate. The differential equations satisfied by eight z-dependent functions are derived for the general case. For the uniform load, the eight functions can be obtained through a step-by-step integration with properly incorporating the boundary conditions at the upper and lower surfaces of the plate. The three-dimensional solutions for functionally graded piezoelectric circular plates with simply-supported or clamped boundary are presented. These solutions can be readily degenerated into those for a homogenous circular plate. Three numerical examples are finally given to show the validity of the analysis, the effect of material heterogeneity and the merits of the present analyses. Since no ad hoc hypotheses on the distribution of the elastic and electric fields are introduced, the present three-dimensional solutions could provide a useful way for checking the validity of various approximate theories and numerical methods.
An Accurate and Efficient Augmented Finite Element Method for Arbitrary Crack Interactions
Authors: Liu W. , Yang Q. D. , Mohammadizadeh S. , Su X. Y. , Ling D. S.
Published: October 2012

This paper presents a new augmented finite element method (A-FEM) that can account for path-arbitrary, multiple intraelemental discontinuities with a demonstrated improvement in numerical efficiency by two orders of magnitude when compared to the extended finite element method (X-FEM). We show that the new formulation enables the derivation of explicit, fully condensed elemental equilibrium equations that are mathematically exact within the finite element context. More importantly, it allows for repeated elemental augmentation to include multiple interactive cracks within a single element without additional external nodes or degrees of freedom (DoFs). A novel algorithm that can rapidly and accurately solve the nonlinear equilibrium equations at the elemental level has also been developed for cohesive cracks with piecewise linear traction-separation laws. This efficient new solving algorithm, coupled with the mathematically exact elemental equilibrium equation, leads to dramatic improvement in numerical accuracy, efficiency, and stability when dealing with arbitrary cracking problems. The A-FEM's excellent capability in high-fidelity simulation of interactive cohesive cracks in homogeneous and heterogeneous solids has been demonstrated through several numerical examples.
Prenatal Stress, Telomere Biology, and Fetal Programming of Health and Disease RiskA Presentation from the European Society for Paediatric Endocrinology (ESPE) New Inroads to Child Health (NICHe) Conference on Stress Response and Child Health in Heraklion, Crete, Greece, 18 to 20 May 2012.
Authors: Entringer Sonja , Buss Claudia , Wadhwa Pathik D.
Published: October 2012

Telomere biology may mediate the effects of intrauterine stress on subsequent newborn, child, and adult health and disease risk outcomes.
Protein Complexes and Target Genes Identification by in Vivo Biotinylation: The STAT5 ParadigmA Presentation from the European Society for Paediatric Endocrinology (ESPE) New Inroads to Child Health (NICHe) Conference on Stress Response and Child Health in Heraklion, Crete, Greece, 18 to 20 May 2012.
Authors: Katsantoni Eleni
Published: October 2012

Identification of a transcription factor’s interacting partners and target genes can reveal context-specific signaling and transcriptional outputs.
Science Signaling
Podcast: 30 October 2012
Authors: Senis Yotis A. , VanHook Annalisa M.
Published: October 2012

Mice lacking an inhibitory receptor have defects in the number, size, and function of platelets.
On the Receiving End
Authors: Hines Pamela J.
Published: October 2012

A protein in a hippocampal postsynaptic neuron templates transmitter release kinetics in its presynaptic neuron.
Conserved Behavioral Controller
Authors: VanHook Annalisa M.
Published: October 2012

A neuropeptide related to oxytocin and vasopressin controls mating behavior and associative learning in nematodes.
A Partner for Smoothened in Cilia
Authors: VanHook Annalisa M.
Published: October 2012

A protein implicated in inherited ciliopathies recruits Smoothened to a ciliary microdomain and is required for Hedgehog signaling.
ERK Activation Without Ras
Authors: Gough Nancy R.
Published: October 2012

The adaptor Bam32 mediates a pathway involving phospholipase C and the kinase Pak to activate the MAPK pathway independently of guanosine triphosphatases.
Inducing Pluripotency Innately
Authors: Andrianantoandro Ernesto
Published: October 2012

Innate immunity signals enable exogenously delivered transcription factors to induce pluripotency.
Family-based association study of ADHD and genes increasing the risk for smoking behaviours
Authors: Thakur Geeta A , Sengupta Sarojini M , Grizenko Natalie , Choudhry Zia , Joober Ridha
Published: October 2012

Objective

To investigate five top single nucleotide polymorphisms (SNPs) located in different genes and loci (CHRNA3, BDNF, DBH and LOC100188947) that were highly associated with different dimensions of smoking behaviour, in relation to attention-deficit hyperactivity disorder (ADHD).

Design

Cohort study consisting of a clinical sample of children with ADHD.

Setting

Douglas Institute ADHD Clinic, Montreal, Canada.

Patients

Families of 454 children with ADHD aged
6–12 years old.

Interventions

Family-based association tests used to study the transmission of risk alleles within these five genetic markers.

Main outcome measures

Clinical diagnosis of ADHD, and a number of behavioural and neurocognitive phenotypes relevant to the disorder.

Results

One SNP (rs1329650) from a non-coding RNA (LOC100188947) was significantly associated with overall ADHD diagnosis with the C* risk allele being over-transmitted from parents to children with ADHD (p=0.02). It was also over-transmitted to children with higher scores on Conners’ Parents (p=0.01) and Conners’ Teacher (p=0.002) index scores, and Child Behaviour Checklist withdrawn (p=0.001) and aggressive (p=0.007) behaviours. Children with poorer performances on executive and attention tasks were more likely to inherit the risk allele.

Conclusions

The C* allele of rs1329650 may be increasing the risk for ADHD and smoking behaviour through a common mechanism, possibly externalising behaviours and specific cognitive deficits that manifest as ADHD in childhood and are the gateway to smoking behaviour later in life. This exploratory study illustrates the use of comorbid disorders to investigate ADHD genetics. In spite of its relatively large sample size, replication in future studies is warranted.

Trial Registration Number

NCT00483106.
A ‘‘not so superficial” skin infection in a patient with diabetes
Authors: Carr James Michael , Hagan Guy , Guest Peter , Gompertz Simon
Published: October 2012

A woman in her 60s with type 2 diabetes presented with a 4-week history of a rash on her chest wall, flu-like symptoms and a red right eye. On examination, there was a cellulitic rash over the right chest wall, breast and neck and a hypopyon in the right eye. Chest x-ray demonstrated right upper lobe opacification, with subsequent CT and MRI revealing bilateral collections at the lung apices, and a possible permeative bone destruction of the manubrium, respectively. A diagnosis of primary sternal osteomyelitis with associated lung abscesses, chest wall cellulitis and hypopyon due to endogenous endophthalmitis was made, with microbiological assessment identifying group B β-haemolytic streptococci. The patient underwent surgical debridement of the affected tissue and received 6 weeks of intravenous antibiotics. This case highlights the role of multidisciplinary team involvement in management of infections and the need to consider deep-seated infection in diabetics.
Illicit ketamine and its bladder consequences: is it irreversible?
Authors: Jalil Rozh , Gupta Suresh
Published: October 2012

Ketamine bladder is a new clinical entity that may lead to irreversible damage to the urinary system. We report the severe lower urinary tract symptoms of four young patients referred to our urology unit who were found to have ulcerative cystitis secondary to ketamine abuse. The pathophysiology remains unclear and the treatment is symptomatic.
A MODEL-INDEPENDENT METHOD TO STUDY DARK MATTER INDUCED LEPTONS AND GAMMA RAYS
Authors: LUO MINGXING , WANG LIUCHENG , ZHU GUOHUAI
Published: October 2012

By using recent data, we directly determine the dark matter (DM)-induced e± spectrum at the source from experimental measurements at the earth, without reference to specific particle physics models. The DM-induced gamma rays emitted via inverse Compton scattering are then obtained in a model-independent way. However, the results depend on the choice of the astrophysical e± background, which is not reliably known. Nevertheless, we calculate, as an illustration, the fluxes of gamma rays from the Fornax cluster in the decaying DM scenario with various astrophysical e± backgrounds. Without any assumptions on details of the DM model, the predictions turn out to be either in disagreement with or only marginally below the upper limits measured recently by the Fermi-LAT Collaboration. In addition, these DM-induced ICS gamma rays in the GeV range are shown to be almost independent of choices of cosmic ray propagation model and of DM density profile, when a given astrophysical e± background is assumed. This provides a strong constraint on decaying DM scenario as the gamma rays may be produced in other processes besides inverse Compton scattering, such as the bremsstrahlung and neutral pion decays.
ABSORPTION OF A PARTICLE BY A ROTATING BLACK HOLE
Authors: HELLER LEON
Published: October 2012

We examine the absorption of a test particle by a near-extreme Kerr black hole, including both positive and negative energy particles. Allowing arbitrary values of the particle's radial momentum at the horizon, we display the region in which the absorption of the particle would "overspin" the black hole and also the region in which it would reduce the area of the black hole. The portions of these regions for a positive energy particle, shrink and disappear as the angular momentum of the initial black hole approaches the extreme Kerr limit. But even in that limit the absorption of a negative energy particle can reduce the area. Proposals to go beyond the test particle approximation are also discussed.
THE FLAVOR SYMMETRY IN THE STANDARD MODEL AND THE TRIALITY SYMMETRY
Authors: FURUI SADATAKA
Published: October 2012

A Dirac fermion is expressed by a four-component spinor, which is a combination of two quaternions and can be treated as an octonion. The octonion possesses the triality symmetry, which defines symmetry of fermion spinors and bosonic vector fields. The triality symmetry relates three sets of spinors and two sets of vectors, which are transformed among themselves via transformations G23, G12, G13, G123 and G132. If the electromagnetic (EM) interaction is sensitive to the triality symmetry, i.e. EM probe selects one triality sector, EM signals from the five transformed world would not be detected and be treated as the dark matter. According to an astrophysical measurement, the ratio of the dark to ordinary matter in the universe as a whole is almost exactly 5. We expect quarks are insensitive to the triality, and triality will appear as three times larger flavor degrees of freedom in the lattice simulation.
CHARGED PION CONDENSATION PHENOMENON OF DENSE BARYONIC MATTER INDUCED BY FINITE VOLUME: THE NJL2 MODEL CONSIDERATION
Authors: EBERT D. , KHUNJUA T. G. , KLIMENKO K. G. , CH. ZHUKOVSKY V.
Published: October 2012

The properties of two-flavored massless Nambu–Jona-Lasinio (NJL) model in (1+1)-dimensional R1 × S1 space–time with compactified space coordinate are investigated in the presence of isospin and quark number chemical potentials μI, μ. The consideration is performed in the large Nc limit, where Nc is the number of colored quarks. It is shown that at L = ∞ (L is the length of the circumference S1) the charged pion condensation (PC) phase with zero quark number density is realized at arbitrary nonzero μI and for rather small values of μ. However, at arbitrary finite values of L the phase portrait of the model contains the charged PC phase with nonzero quark number density (in the case of periodic boundary conditions for quark fields). Hence, finite sizes of the system can serve as a factor promoting the appearance of the charged PC phase in quark matter with nonzero baryon densities. In contrast, the phase with chiral symmetry breaking may exist only at rather large values of L.
A UNIFORM APPROACH TO EXPLORING THE BELL-TYPE SOLITARY WAVE SOLUTIONS OF NONLINEAR EVOLUTION EQUATIONS
Authors: XIE YUANXI , PENG SHIYU , SU KALIN
Published: October 2012

By introducing a transformation containing two unknown functions and selecting appropriate trial functions, we develop a simple and unified approach to construct the bell-type solitary wave solutions of nonlinear evolution equations (NEEs). We demonstrate the effectiveness of our approach by applications to some physically significant equations as particular examples. The procedure used herein can also be applied to seek the bell-type solitary wave solutions of other NEEs.