bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerodynamic modelling of flapping flight using lifting line theory
Authors: Bhowmik Joydeep , Das Debopam , Ghosh Saurav Kumar
Published: February 2013

Purpose

The purpose of the work is to design a flapping wing that generates net positive propulsive force and vertical force over a flapping cycle operating at a given freestream velocity. In addition, an optimal wing is designed based on the comparison of the force estimated from the quasi‐steady theory, with the wind‐tunnel experiments. Based on the designed wing configuration, a flapping wing ornithopter is fabricated.

Design/methodology/approach

This paper presents a theoretical aerodynamic model of the design of an ornithopter with specific twist distribution that results generation of substantial net positive vertical force and thrust over a cycle at non‐zero advance ratio. The wing has a specific but different twist distribution during the downstroke and the upstroke that maintains the designed angle of attack during the strokes. The wing is divided into spanwise strips and Prandtl's lifting line theory is applied to estimate aerodynamic forces with the assumptions of quasi‐steady flow and the wings are without any dihedral or anhedral. Spanwise circulation distribution is obtained and hence lift is calculated. The lift is resolved along the freestream velocity and perpendicular to the freestream velocity to obtain vertical force and propulsive thrust force. Experiments are performed in a wind tunnel to find the forces generated in a flapping cycle which compares well with the theoretical estimation at low flying speeds.

Findings

The estimated aerodynamic force indicates whether the wing geometry and operating conditions are sufficient to carry the weight of the vehicle for a sustainable flight. The variation of the aerodynamic forces with varying flapping frequencies and freestream velocities has been illustrated and compared with experimental data that shows a reasonable match with the theoretical estimations. Based on the calculations a prototype has been fabricated and successfully flown.

Research limitations/implications

The theory does not take into account the unsteady effects and estimates the aerodynamic forces at wing level condition. It doesn’t predict stall and ignores structural deformations due to aerodynamic loads. The airfoil section is only specified by the chord, zero lift angle of attack, lift slope, profile drag coefficient and angle of attack as given inputs. To fabricate a light weight wing that maintains a very accurate geometric twist and camber distribution as per the theoretical requirement is challenging.

Practical implications

Useful for designing ornithopter wing (preferably bigger) involving an unswept rigid spar with flapping and twisting.

Originality/value

The novelty of the present wing design is the appropriate spanwise geometric twisting about the leading edge spar.
Generalization of learned predator recognition in coral reef ecosystems: how cautious are damselfish?
Authors: Mitchell Matthew D. , McCormick Mark I. , Chivers Douglas P. , Ferrari Maud C. O.
Published: February 2013

Learned predator recognition provides animals with an adaptive mechanism to rapidly adapt to current levels of predation risk. Prey may be able to reduce the cost associated with learning if they can use information learned about known predators to respond to cues from closely related predators with which they are unfamiliar.

The capacity of prey to generalize recognition and distinguish between novel predators and non‐predators is poorly understood, particularly in species‐diverse communities with many closely related predators and non‐predators.

Lemon damselfish, Pomacentrus moluccensis, conditioned to recognize the odour of a predatory moon wrasse, Thalassoma lunare, as a risky stimulus, were subsequently tested for their response to T. lunare and a range of closely related predators and non‐predators from within the Labridae family, a distantly related non‐predator and a saltwater control.

Pomacentrus moluccensis displayed antipredator responses not only to T. lunare odour, but also generalized their recognition to congeneric T. amblycephalum and T. hardwicke odours. Recognition was not extended to other species within (Labridae; Coris batuensis and Halichoeres melanurus) or beyond (Pseudochromidae; Pseudochromis fuscus) the family. Individuals could not distinguish between the predator T. hardwicke and non‐predator T. amblycephalum when generalizing their recognition to congeneric species based on chemosensory assessment alone.

Our results demonstrate that reef fishes may limit their generalization to congeneric species only, and may be unable to distinguish between predators and non‐predators using chemosensory cues. Recognition patterns may result from uncertainties in predicting the identities of predators in species‐diverse communities.
Neuroscientists’ everyday experiences of ethics: the interplay of regulatory, professional, personal and tangible ethical spheres
Authors: Brosnan Caragh , Cribb Alan , Wainwright Steven P. , Williams Clare
Published: February 2013

The ethical issues neuroscience raises are subject to increasing attention, exemplified in the emergence of the discipline neuroethics. While the moral implications of neurotechnological developments are often discussed, less is known about how ethics intersects with everyday work in neuroscience and how scientists themselves perceive the ethics of their research. Drawing on observation and interviews with members of one UK group conducting neuroscience research at both the laboratory bench and in the clinic, this article examines what ethics meant to these researchers and delineates four specific types of ethics that shaped their day‐to‐day work: regulatory, professional, personal and tangible. While the first three categories are similar to those identified elsewhere in sociological work on scientific and clinical ethics, the notion of ‘tangible ethics’ emerged by attending to everyday practice, in which these scientists’ discursive distinctions between right and wrong were sometimes challenged. The findings shed light on how ethical positions produce and are, in turn, produced by scientific practice. Informing sociological understandings of neuroscience, they also throw the category of neuroscience and its ethical specificity into question, given that members of this group did not experience their work as raising issues that were distinctly neuro‐ethical.
DNA Barcodes indicate members of the Anopheles fluviatilis (Diptera: Culicidae) species complex to be conspecific in India
Authors: Pradeep kumar N. , Krishnamoorthy N. , Sahu S. S. , Rajavel A. R. , Sabesan S. , Jambulingam P.
Published: February 2013

Anopheles fluviatilis, a major vector of malaria in India has been described as a complex of three sibling species members, named as S, T and U, based on variations in chromosomal inversions. Also, ribosomal DNA markers (repetitive Internal Transcribed Spacer 2 (ITS2) and 28S D3 region) were described to differentiate these three sibling species members. However, controversies prevail on the genetic isolation status of these cryptic species. Hence, we evaluated this taxonomic incongruence employing DNA barcoding, the well established methodology for species identification, using 60 An. fluviatilis sensu lato specimens, collected from two malaria endemic eastern states of India. These specimens were also subjected to sibling species characterization by ITS2 and D3 DNA markers. The former marker identified 31 specimens among these as An. fluviatilis S and 21 as An. fluviatilis T. Eight specimens amplified DNA fragments specific for both S and T. The D3 marker characterized 39 specimens belonging to species S and 21 to species T. Neither marker identified species U. Neighbor Joining analysis of mitochondrial cytochrome c oxidase gene 1 sequences (the DNA barcode) categorized all the 60 specimens into a single operational taxonomic unit, their Kimura 2 parameter (K2P) genetic variability being only 0.8%. The genetic differentiation (FST) and gene flow (Nm) estimates were 0.00799 and 62.07, respectively, indicating these two ‘species’ (S & T) as genetically con‐specific intermixing populations with negligible genetic differentiation. Earlier investigations have refuted the existence of species U. Also, this study demonstrated that An. fluviatilis and the closely related An. minimus could be taxonomically differentiated by the DNA Barcode approach (K2P = 5.0%).
Comparison of the Abbott RealTime High Risk HPV with Genomica HPV Clinical Array for the detection of human papillomavirus DNA
Authors: Sias Catia , Garbuglia Anna Rosa , Piselli Pierluca , Cimaglia Claudia , Lapa Daniele , Nonno Franca Del , Baiocchini Andrea , Capobianchi Maria Rosaria
Published: February 2013

Human papillomavirus (HPV) has been identified as the major cause of cervical cancer worldwide and HPV DNA testing is recommended in primary cervical cancer screening. Several molecular tests for detection/typing of HPV DNA with different sensitivity and specificity are commercially available. The present study compared the performance of the Abbott RealTime High Risk HPV assay and the Genomica HPV Clinical Array CLART2 in 78 specimens (63 cervical smears and 15 rectal/urethral swabs).The typing results of the Genomica assay were in absolute agreement with each of the four possible result categories of the Abbott assay (HPV16, HPV18, Other HR HPV, not detected) in 87.2% (68/78) of the samples, with a Cohen' kappa agreement coefficient for every HR type of 0.62 (95% CI: 0.39–0.85), higher in cervical swabs (k = 0.74, 95% CI: 0.50–0.99) than in rectal/urethral swabs (k = 0.36, 95% CI: 0.00–0.82). There was an excellent agreement of the Genomica results with those of Abbott in cervical samples harbored HPV single infection (100% agreement). Nonetheless, both methods may lose sensitivity for detecting HPV types in multiple infections, giving discordant results (10/78). This underlines the importance of establishing the analytical sensitivity in HPV type detection in single and multiple HPV infections.

In rectal/urethral swabs, 5 of 15 (33%) discordant cases were observed, most of which became compatible when the Genomica assay was performed starting from nucleic acid extracted with the Abbott m2000sp system. These results suggest that nucleic extraction based on the magnetic beads technique is suitable for HPV DNA detection in urethral/rectal swabs.
Restorative proctocolectomy impairs fertility and pregnancy outcomes in women with ulcerative colitis
Authors: Tulchinsky H. , Averboukh F. , Horowitz N. , Rabau M. , Klausner J. M. , Halpern Z. , Dotan I.
Published: February 2013

Aim

The effect of restorative proctocolectomy (RPC) on fertility and pregnancy in women with ulcerative colitis (UC) was evaluated.

Method

Post‐RPC female patients with UC who were attempting to become pregnant filled out questionnaires on fertility and pregnancy. Demographic and pouch data of pregnancies ending with delivery were collected from a prospective database.

Results

Forty‐one women, 44 ± 10 years of age, completed the questionnaires. The median follow‐up period post‐RPC was 167 (range, 20–352) months. Before RPC, 26 women had 70 pregnancies and 62 deliveries. After RPC, 17 women had 32 pregnancies and 26 deliveries (P = 0.0035). Post‐RPC, 10 (37%) of 27 patients failed to conceive compared with 26/26 successful attempts before RPC (P = 0.0006). The number of offspring per patient was 2.38 ± 1.27 before, and 0.68 ± 0.93 after, RPC (P < 0.0001). A higher number of spontaneous pregnancies occurred before (56/62; 90%) than after (15/25; 60%) RPC (P = 0.0004). The time to conception was longer (5.0 ± 11.6 vs 16.3 ± 25.1 months; P = 0.039) and there were more in‐vitro fertilization procedures (three vs six) post‐RPC. The gestation period was similar, but after RPC more deliveries were by Caesarean section (12.9% vs 46.2%; P = 0.0007). Babies born before RPC weighed more than those born after RPC (3.16 ± 0.61 kg vs 2.79 ± 0.68 kg, respectively; P = 0.0327).

Conclusion

RPC is associated with an increased risk of infertility, similar duration of gestation and lower birthweight. Female candidates for RPC who have not finished family planning should be counselled accordingly.
Should paediatric stroke be treated as adult stroke?
Authors: Kossorotoff Manoëlle
Published: February 2013

This commentary is on the original article by Lagman‐Bartolome et al. on pages 434–439 of this issue.
Ventilation in ALS
Authors: Swash M.
Published: February 2013

Click here to view the accompanying paper in this issue.
Approach towards developing a novel procedure to selectively quantify topically applied substances in the hair follicles of the model tissue porcine ear skin
Authors: Knorr Fanny , Patzelt Alexa , Richter Heike , Schanzer Sabine , Sterry Wolfram , Lademann Juergen
Published: February 2013

Hair follicles represent reservoirs for localized drug therapy and transport pathways for systemic drug delivery. This study describes an approach towards developing a novel procedure for quantifying topically applied substances located in the hair follicles of porcine ear skin, a model for human in vivo skin, using a fluorescent dye. Approximately 5% of the topically applied dye was recovered from the hair follicles, which is in accordance with a previous study.
NF1 gene silencing induces upregulation of vascular endothelial growth factor expression in both Schwann and non‐Schwann cells
Authors: Kawachi Yasuhiro , Maruyama Hiroshi , Ishitsuka Yosuke , Fujisawa Yasuhiro , Furuta Junichi , Nakamura Yasuhiro , Ichikawa Eiko , Furumura Minao , Otsuka Fujio
Published: February 2013

Neurofibromatosis type I (NF1) is associated with typical hypervascular tumors, including neurofibroma, glioma, malignant peripheral nerve sheath tumors (MPNST) and glomus tumors. Previously, we and other groups reported that neurofibromas showed high‐level expression of vascular endothelial growth factor (VEGF), a potent angiogenic factor involved in neovascularization. However, the molecular mechanism underlying the upregulation of VEGF in neurofibromas remains unclear. In this study, we examined the effects of Nf1 gene silencing on VEGF expression in Schwann cell and non‐Schwann cell line and the upstream mTOR‐HIF‐1α – VEGF pathway in Schwann cell line. The results indicated that Nf1 gene silencing by lentiviral‐mediated RNA interference resulted in elevated expression of VEGF, HIF‐1α and phosphorylated mTOR at the protein level. The results obtained from Nf1 gene silencing in murine Schwann cell line analogously suggest that NF1 gene haploinsufficiency in human tumor Schwann cells may directly elicit upregulation of VEGF expression without the tumor microenvironment by activation of the mTOR‐HIF‐1α – VEGF pathway. We also showed that interleukin‐6 is upregulated in Nf1 gene knock‐down Schwann cells at the protein level.
Detection and Molecular Variability of Apple Stem Grooving Virus in Shaanxi, China
Authors: Liu Ping , Zhang Lei , Zhang Huawei , Jiao Honghong , Wu Yunfeng
Published: February 2013

Apple stem grooving virus (ASGV) is one of the economically important latent viruses that are distributed in apple production areas worldwide. The presence of ASGV in apple trees was studied by serological assay and molecular biology methods. A total of 550 apple leaf samples from 14 different areas in Shaanxi were tested by DAS‐ELISA, and the results revealed an ASGV infection level of 55%. Those samples were also examined by RT‐PCR, and an infection level of 67% was found. Fourteen complete coat protein gene sequences of ASGV were obtained; phylogenetic analysis revealed that these 14 sequences separated into two clusters regardless of the geographic origin or host plants. To our knowledge, this is the first report of molecular variability analysis of ASGV in apple trees in China.
Isolation of clonal axenic strains of the symbiotic dinoflagellate Symbiodinium and their growth and host specificity1
Authors: Xiang Tingting , Hambleton Elizabeth A. , DeNofrio Jan C. , Pringle John R. , Grossman Arthur R.
Published: February 2013

The cnidarian‐dinoflagellate mutualism is integral to the survival of the coral‐reef ecosystem. Despite the enormous ecological and economic importance of corals, their cellular and molecular biology and the ways in which they respond to environmental change are still poorly understood. We have been developing a proxy system for examining the coral mutualism in which the dinoflagellate symbiont Symbiodinium is introduced into a clonal population of the host Aiptasia, a small sea anemone closely related to corals. To further develop the tools for this system, we generated five clonal, axenic strains of Symbiodinium and verified the lack of contaminants by growth on rich medium, microscopic examination, and PCR analysis. These strains were assigned to clades A (two strains), B, E, and F based on their chloroplast 23S rDNA sequences. Growth studies in liquid cultures showed that the clade B strain and one of the clade A strains were able to grow photoautotrophically (in light with no fixed carbon), mixotrophically (in light with fixed carbon), or heterotrophically (in dark with fixed carbon). The clade E strain, thought to be free‐living, was able to grow photoautotrophically but not heterotrophically. Infection of an aposymbiotic Aiptasia host with the axenic strains showed consistent patterns of specificity, with only the clade B and one of the clade A strains able to successfully establish symbiosis. Overall, the Aiptasia‐Symbiodinium association represents an important model system for dissecting aspects of the physiology and cellular and molecular biology of cnidarian‐dinoflagellate mutualism and exploring issues that bear directly on coral bleaching.
Fibroblast Growth Factor 23 in Feline Chronic Kidney Disease
Authors: Geddes R.F. , Finch N.C. , Elliott J. , Syme H.M.
Published: February 2013

Background

Fibroblast growth factor 23 (FGF‐23) is a phosphaturic hormone involved in the pathogenesis of secondary renal hyperparathyroidism (SRHP) in humans. There are no published studies examining feline FGF‐23.

Objectives

Validation of a method for FGF‐23 quantification in feline plasma and assessment of the associations among plasma FGF‐23, PTH, creatinine, and phosphate concentrations in cats with chronic kidney disease (CKD).

Animals

One hundred nonazotemic and azotemic geriatric (>9 years) client‐owned cats.

Methods

Retrospective cross‐sectional study: Cats were categorized into 4 groups: control group (plasma creatinine (Cr) ≤2.0 mg/dL), stage 2 (Cr 2.1–2.8 mg/dL), stage 3 (Cr 2.9–5.0 mg/dL), stage 4 (Cr >5.0 mg/dL). Stages 2 and 3 were further subdivided based on International Renal Interest Society targets for plasma phosphate concentration (PO4): stage 2a (PO4 ≤4.5 mg/dL), stage 2b (PO4 >4.5 mg/dL), stage 3a (PO4 ≤5 mg/dL), stage 3b (PO4 >5 mg/dL). Plasma FGF‐23 concentrations were measured by a human intact FGF‐23 ELISA. Descriptive statistics and linear regression were performed.

Results

The ELISA demonstrated acceptable precision, reproducibility, and specificity. Plasma FGF‐23 concentrations increased with increasing plasma creatinine concentrations and were significantly different between all groups (P < .008). Plasma FGF‐23 concentrations were significantly higher in cats in stage 2b than stage 2a (P = .008) and in stage 3b than in stage 3a (P = .012). Phosphate, log creatinine, total calcium, log parathyroid hormone, and packed cell volume were all independent predictors of FGF‐23.

Conclusions and Clinical Importance

FGF‐23 concentrations increase with increasing stage of feline CKD and might be a marker or mediator of feline SRHP.
History of Reading: The long Eighteenth Century
Authors: Bannet Eve Tavor
Published: February 2013

Describes recent developments in this interdisciplinary field, showing how they alter our previous assumptions about eighteenth‐century reading; indicates lacunae and opportunities for future work.
Postscript on Credibility
Authors: McDade John
Published: February 2013

The article considers some of the factors relevant to the question of the credibility of Christian faith. It argues that atheism is a product of a certain kind of Western Christianity: when you exceed the boundaries of what can be said about God and create “religion”, at the same time you create the conditions for disbelief in that religion. Nietzsche is a point of reference for various aspects of the question which centres on the status of “God” in relation to religious narratives that have lost power. How might Christians conduct themselves in the “Courtyard of the Gentiles” that Pope Benedict proposes?
Church, Culture and Credibility: A Perspective from Ireland
Authors: Regan Ethna
Published: February 2013

This article explores the crisis in the Catholic Church in Ireland in light of the child-abuse scandals exposed in recent reports and outlines some of the theological responses to that crisis. It suggests that it is necessary to examine not just the crimes of the perpetrators of abuse and the inadequate response of individual church leaders but also the structural sin within the Church that is at the root of the crisis. It is argued that the collusion between Church and State in modern Ireland that emerges from these reports can be defined in terms of Hiberno-Christendom, drawing from Charles Taylor definition of “Christendom”. In the midst of the crisis, the ongoing revelations of clerical abuse and the accompanying analysis, there is still pastoral vibrancy and people are trying to cultivate hope. The Catholic Church in Ireland may need to learn how to become what Juan Luis Segundo calls a “creative minority”, re-imagining the parameters of its power and developing a new political theology.
Faith in Culture
Authors: Sweeney James
Published: February 2013

This article, working within a sociological framework, discusses the issues and challenges arising at the church-culture interface, which are of central importance for ecclesial credibility, many of which came up in the 2012 Synod of Bishops on the New Evangelization. It suggests that, while there are evident problems with postmodern culture, the key problem lies within the Church itself, in the disconnect between contemporary modes of cultural production and the dominant mode of transmission of the Christian faith. The remedy would be a presentation of the gospel and an ecclesial witness that is deeply respectful of individuals searching for authentic ways of living and that invites and enables them to find in a renewed church the path to true freedom.
Radio‐protective effects of Nigella sativa oil on oxidative stress in tongue tissue of rats
Authors: Üstün K , Taysı S , Sezer U , Demir E , Baysal E , Demir T , Sarıçiçek E , Alkış H , Şenyurt SZ , Tarakçıoğlu M , Aksoy N
Published: February 2013

Objective

The aim of this study was to evaluate the effects of Nigella sativa (N.S.) oil against radiation‐induced oxidative stress in the rat tongue.

Material and Methods

Thirty‐two Sprague‐Dawley rats were randomly divided into four equal groups. Group 1 [control group(C)] did not receive N.S. oil or irradiation. Group 2 [sham control group(CN)] did not receive N.S. oil or irradiation but received 1‐ml saline orally, plus sham irradiation. Group 3 [irradiation group(R)] received irradiation, plus 1‐ml saline orally. Group 4 [irradiation plus N.S. oil group(RN)] received irradiation plus 1 g kg−1 per day of N.S. oil orally for 10 days. The animals were euthanized on day 10, and tongue tissues were collected for evaluating biochemical oxidative parameters.

Results

The oxidative stress index, total oxidant status and lipid hydroperoxides levels in the R group were statistically higher than those in the C, CN and RN groups. The paraoxonase levels in the R group were statistically lower than those in the C, CN and RN groups. No statistically significant differences were detected between any of the groups, in terms of total antioxidant status and the arylesterase, ceruloplasmin and total sulfhydryl group levels.

Conclusion

Nigella sativa (N.S.) oil may be a beneficial agent in protecting against ionizing radiation‐related tissue injury.
Polymorphism of the Melatonin Receptor Genes and its Relationship with Seasonal Reproduction in the Gulin Ma Goat Breed
Authors: Lai P , Zhang BY , Wang PQ , Chu MX , Song WJ , Cai BJ
Published: February 2013

Contents

Melatonin is thought to be the main molecule that transmits the signal of seasonal change to the neuroendocrine system in seasonal breeding species. Melatonin exerts its effects through specific melatonin receptors, MTNR1A and MTNR1B. In the present study, six native goat breeds in China and one introduced goat breed were analysed to investigate the relationship between the genetic polymorphism of receptor genes and seasonal reproduction. Sequencing results showed that there were five polymorphic mutations in the MTNR1A gene and two in the MTNR1B gene. In the MTNR1A gene, genotypes AA, AB and BB for 424C>T and genotypes CC, CD and DD for 589C>A were observed in these goat breeds. In all six native goat breeds, only genotype AA was detected. In the MTNR1B gene, genotypes EE, EF and FF for 1179G>A and genotypes GG, GH and HH for 1529A>G were detected. However, in Gulin Ma goats, the genotypes EE and HH were not found. Moreover, the base of G at position 1179 and A at position 1529 were linked (By Arlequin ver 3.1, Zoological Institute, Berne, Switzerland, http://cmpg.unibe.ch/software/arlequin3,D′ = 0.7496, r2 = 0.4421, χ2 = 489.8679, p = 0.000). Among these mutations, no amino acid change was found in MTNR1A, while both of the mutations in MTNR1B gene caused amino acid changes of R222H and S339G, respectively. The structural analysis showed that the R222H mutation occurred in the first amino acid residue of the third cytoplasmic loop, and the S339G mutation was located in the carboxyl terminus of the protein. In terms of seasonal breeding, all the genotypes we detected showed a similar kidding frequency distribution trend with a higher frequency in May–August than in January–April and in September–December. This suggests that the relationship between the polymorphisms in the MTNR1A and MTNR1B genes and seasonal breeding could not be established.
An Empirical Approach to Sufficient Similarity: Combining Exposure Data and Mixtures Toxicology Data
Authors: Marshall Scott , Gennings Chris , Teuschler Linda K. , Stork LeAnna G. , Tornero‐Velez Rogelio , Crofton Kevin M. , Rice Glenn E.
Published: February 2013

When assessing risks posed by environmental chemical mixtures, whole mixture approaches are preferred to component approaches. When toxicological data on whole mixtures as they occur in the environment are not available, Environmental Protection Agency guidance states that toxicity data from a mixture considered “sufficiently similar” to the environmental mixture can serve as a surrogate. We propose a novel method to examine whether mixtures are sufficiently similar, when exposure data and mixture toxicity study data from at least one representative mixture are available. We define sufficient similarity using equivalence testing methodology comparing the distance between benchmark dose estimates for mixtures in both data‐rich and data‐poor cases. We construct a “similar mixtures risk indicator”(SMRI) (analogous to the hazard index) on sufficiently similar mixtures linking exposure data with mixtures toxicology data. The methods are illustrated using pyrethroid mixtures occurrence data collected in child care centers (CCC) and dose‐response data examining acute neurobehavioral effects of pyrethroid mixtures in rats. Our method shows that the mixtures from 90% of the CCCs were sufficiently similar to the dose‐response study mixture. Using exposure estimates for a hypothetical child, the 95th percentile of the (weighted) SMRI for these sufficiently similar mixtures was 0.20 (i.e., where SMRI <1, less concern; >1, more concern).
Thermoelectric Performance of Novel Composite and Integrated Devices Applied to Waste Heat Recovery
Authors: Reddy B. V. K. , Barry Matthew , Li John , Chyu Minking K.
Published: February 2013

Thermoelectric elements, made of semiconductor slices laminated onto highly conductive interconnector materials, are termed composite thermoelectric device (TED). An integrated TED is a composite TED with the interconnector designed as an internal heat exchanger with flow channels directing the working fluid between the source and element legs. In this work, novel composite and integrated TEDs are proposed as an alternative to conventional TEDs, and their performance in terms of power output P0, heat input Qh, conversion efficiency η, and the produced electrical current I is studied using analytical solutions. The top and bottom surfaces of the TED are subjected to a temperature differential while the side surfaces are exposed to either ambient or adiabatic conditions. An increment in temperature differential results in enhanced device performance. For a fixed temperature differential, the integrated TED shows nearly an eight-fold increase in both P0 and Qh and a four-fold increase in I, whereas the composite TED shows approximately a two-fold increase in P0, Qh, and I when compared to the conventional TED values. Both novel TED designs have a minimal impact on efficiency predictions. However, an increase in semiconductor slice thickness resulted in an exponential decrease in P0, Qh, and I, and an exponential increase in η values and reaches a limit of conventional TED values. The effect of semiconductor slice thickness on η in the novel TEDs is remarkable when it is less than 1 mm. The change in ambient conditions via convective heat transfer coefficient has negligible effects on P0; however, a substantial change in η occurs when it is less than 100 Wm-2K-1.
A Variational Boundary Element Formulation for Shear-Deformable Plate Bending Problems
Authors: Naga Taha H. A. , Rashed Youssef F.
Published: February 2013

This paper presents the derivation of a new boundary element formulation for plate bending problems. The Reissner's plate bending theory is employed. Unlike the conventional direct or indirect formulations, the proposed integral equation is based on minimizing the relevant energy functional. In doing so, variational methods are used. A collocation based series, similar to the one used in the indirect discrete boundary element method (BEM), is used to remove domain integrals. Hence, a fully boundary integral equation is formulated. The main advantage of the proposed formulation is production of a symmetric stiffness matrix similar to that obtained in the finite element method. Numerical examples are presented to demonstrate the accuracy and the validity of the proposed formulation.
On Solving One-Dimensional Partial Differential Equations With Spatially Dependent Variables Using the Wavelet-Galerkin Method
Authors: Jones Simon , Legrand Mathias
Published: February 2013

The discrete orthogonal wavelet-Galerkin method is illustrated as an effective method for solving partial differential equations (PDE's) with spatially varying parameters on a bounded interval. Daubechies scaling functions provide a concise but adaptable set of basis functions and allow for implementation of varied loading and boundary conditions. These basis functions can also effectively describe C0 continuous parameter spatial dependence on bounded domains. Doing so allows the PDE to be discretized as a set of linear equations composed of known inner products which can be stored for efficient parametric analyses. Solution schemes for both free and forced PDE's are developed; natural frequencies, mode shapes, and frequency response functions for an Euler–Bernoulli beam with piecewise varying thickness are calculated. The wavelet-Galerkin approach is shown to converge to the first four natural frequencies at a rate greater than that of the linear finite element approach; mode shapes and frequency response functions converge similarly.
Fabrication of multiscale electrodes on organic photovoltaic thin films and in situ electrical characterization by nanostencil combined with Qplus AFM
Authors: Grévin Benjamin , Jradi Khalil , Nisa Yahya Wan Zaireen , De Bettignies Rémi , Demadrille Renaud
Published: February 2013

The authors demonstrate the fabrication of multiscale electrodes (with lateral dimensions ranging from 10 μm to a few hundred of nanometers) on organic donor–acceptor photovoltaic thin films by mean of nanostencil lithography. The experimental setup allows the realization and in situ investigation of structures by combining nanostencil and atomic force microscopy (AFM) capabilities based on the use of tuning forks. Qplus AFM sensors with tungsten etched tips were used for near field imaging, and as microprobes to contact the deposited electrodes. The photovoltaic behavior was characterized by mean of current–voltage measurements in dark and under selective illumination. The influence of the electrode geometry on the electrical parameters is analyzed and the effect of in situ annealing is discussed in view of frequency modulation AFM images of the active layer surface morphology. This illustrates the powerfulness of nanostencil combined with Qplus AFM for local investigations of organic photovoltaic materials and in situ fabrication of devices.
Effects of severe caloric restriction from birth on the hearts of adult rats
Authors: Melo Dirceu Sousa , Riul Tania Regina , Esteves Elizabeth Adriana , Moraes Patrícia Lanza , Ferreira Fernanda Oliveira , Gavioli Mariana , Alves Márcia Netto Magalhães , Almeida Pedro William Machado , Guatimosim Silvia , Ferreira Anderson José , Dias Peixoto Marco Fabricio
Published: February 2013

There has been increasing evidence suggesting that a severe caloric restriction (SCR) (above 40%) has beneficial effects on the hearts of rats. However, most of the reports have focused on the effects of SCR that started in adulthood. We investigated the consequences of SCR on the hearts of rats subjected to SCR since birth (CR50). From birth to the age of 3 months, CR50 rats were fed 50% of the food that the ad libitum group (AL) was fed. Thereafter, a maximal aerobic test was performed to indirectly evaluate global cardiovascular function. Indices of contractility (+dT/dt) and relaxation (−dT/dt) were analyzed in isolated heart preparation, and cardiomyocyte diameter, number, density, and myocardium collagen content were obtained through histologic analysis. Ventricular myocytes were isolated, using standard methods to evaluate phosphorylated AKT levels, and Ca2+ handling was evaluated with a combination of Western blot analysis, intracellular Ca2+ imaging, and confocal microscopy. CR50 rats exhibited increased aerobic performance and cardiac function, as shown by the increase in ±dT/dt. Despite the smaller cardiomyocyte diameter, CR50 rats had an increased heart−body weight ratio, increased cardiomyocyte density and number, and similar levels of myocardium collagen content, compared with AL rats. AKT was hyperphosphorylated in cardiomyocytes from CR50 rats, and there were no significant differences in Ca2+ transient and SERCA2 levels in cardiomyocytes between CR50 and AL rats. Collectively, these observations reveal the beneficial effects of a 50% caloric restriction on the hearts of adult rats restricted since birth, which might involve cardiomyocyte AKT signaling.
Influence of water on diffusion and porosity parameters of soil–cement materials
Authors: Goreham Vincent C. , Lake Craig B.
Published: February 2013

In this paper a conservative tracer (tritiated water) is used to assess the diffusive properties of 14 different laboratory-prepared soil–cement mixtures. A single-reservoir diffusion test setup to determine the effective porosity (ne) and the effective diffusion coefficient (De) through saturated, monolithic, soil–cement materials is used to assess the importance of mixture design on ne and De. Values of De and ne were found to range from 2.5 × 10−10 to 7.0 × 10−10 m2/s and from 0.21 to 0.41, respectively. Results indicate that the water content of the initial mixture has a substantial effect on the diffusive properties of the soil–cement material. The results suggest, from a contaminant transport perspective, that designers should generally aim to minimize the water content of cement-based solidification–stabilization materials.
Applications of rare event dynamics on the free energy calculations for membrane protein systems
Authors: Wang Yun-Kun , Wei Dong-Qing , Gu Ruo-Xu , Fan Huai-Meng , Ulmschneider Jakob
Published: February 2013

Techniques of rare event dynamics were reviewed, including string methods, which will be implemented with the biochemical simulation packages. The existing methods were applied to study biological systems with relevance to drug design and drug metabolism. The rare event dynamics simulations were performed to understand the kinetic and thermodynamic free energy information on the drug binding sites in the M2 proton channel, the free energy of insertion and association of membrane proteins and membrane active peptides. Results give a theoretical framework to interpret and reconcile existing and often conflicting opinions.
A density functional study of Rh13
Authors: Calaminici Patrizia , Vásquez-Pérez José M. , Espíndola Velasco Diego A.
Published: February 2013

A density functional study was performed for the Rh13 cluster using the linear combination of Gaussian-type orbitals density functional theory (LCGTO-DFT) approach. The calculations employed both the local density approximation (LDA) as well as the generalized gradient approximation (GGA) in combination with a quasi-relativistic effective core potential (QECP). Initial structures for the geometry optimization were taken along Born–Oppenheimer molecular dynamics (BOMD) trajectories. The BOMD trajectories were performed at different temperatures and considered different potential energy surfaces (PES). As a result, several hundred isomers of the Rh13 cluster in different spin multiplicities were optimized with the aim to determine the lowest energy structures. All geometry optimizations were performed without any symmetry restriction. A vibrational analysis was performed to characterize these isomers. Structural parameters, relative stability energy, harmonic frequencies, binding energy, and most relevant Kohn–Sham (KS) molecular orbitals are reported. The obtained results are compared with available data from the literature. This study predicts a low symmetry biplanarlike structure as the ground-state structure of Rh13 with 11 unpaired electrons. This isomer was first noticed by inspection of first-principle Born–Oppenheimer molecular dynamics (BOMD) simulations between 300 and 600 K. This represents the most extensive theoretical study on the ground-state structure of the Rh13 cluster and underlines the importance of BOMD simulations to fully explore the PES landscapes of complicated systems.
An Assessment of Maintainability of an Aspect-Oriented System
Authors: Mguni Kagiso , Ayalew Yirsaw
Published: February 2013

Software maintenance is an important activity in software development. Some development methodologies such as the object-oriented have contributed in improving maintainability of software. However, crosscutting concerns are still challenges that affect the maintainability of OO software. In this paper, we discuss our case study to assess the extent of maintainability improvement that can be achieved by employing aspect-oriented programming. Aspect-oriented programming (AOP) is a relatively new approach that emphasizes dealing with crosscutting concerns. To demonstrate the maintainability improvement, we refactored a COTS-based system known as OpenBravoPOS using AspectJ and compared its maintainability with the original OO version. We used both structural complexity and concern level metrics. Our results show an improvement of maintainability in the AOP version of OpenBravoPOS.
A Cost Model for Integrated Logistic Support Activities
Authors: Nenni M. Elena
Published: February 2013

An Integrated Logistic Support (ILS) service has the objective of improving a system’s efficiency and availability for the life cycle. The system constructor offers the service to the customer, and she becomes the Contractor Logistic Support (CLS). The aim of this paper is to propose an approach to support the CLS in the budget formulation. Specific goals of the model are the provision of the annual cost of ILS activities through a specific cost model and a comprehensive examination of expected benefits, costs and savings under alternative ILS strategies. A simple example derived from an industrial application is also provided to illustrate the idea. Scientific literature is lacking in the topic and documents from the military are just dealing with the issue of performance measurement. Moreover, they are obviously focused on the customer’s perspective. Other scientific papers are general and focused only on maintenance or life cycle management. The model developed in this paper approaches the problem from the perspective of the CLS, and it is specifically tailored on the main issues of an ILS service.
Dkk-3, a Secreted Wnt Antagonist, Suppresses Tumorigenic Potential and Pulmonary Metastasis in Osteosarcoma
Authors: Lin Carol H. , Guo Yi , Ghaffar Samia , McQueen Peter , Pourmorady Jonathan , Christ Alexander , Rooney Kevin , Ji Tao , Eskander Ramez , Zi Xiaolin , Hoang Bang H.
Published: February 2013

Osteosarcoma (OS) is the most common primary bone malignancy with a high propensity for local invasion and distant metastasis. Despite current multidisciplinary treatments, there has not been a drastic change in overall prognosis within the past 2 decades. Dickkopf-3 protein (Dkk-3/REIC) has been known to inhibit canonical Wnt/β-catenin pathway, and its expression has been shown to be downregulated in OS cell lines. Usingin vivoandin vitrostudies, we demonstrated that Dkk-3-transfected 143B cells inhibited tumorigenesis and metastasis in an orthotopic xenograft model of OS. Inoculation of Dkk-3-transfected 143B cell lines into nude mice showed significant decreased tumor growth and less metastatic pulmonary nodules (88.7%) compared to the control vector.In vitroexperiments examining cellular motility and viability demonstrated less anchorage-independent growth and decreased cellular motility for Dkk-3-transfected 143B and SaOS2 cell lines compared to the control vector. Downstream expressions of Met, MAPK, ALK, and S1004A were also downregulated in Dkk-3-transfected SaOS2 cells, suggesting the ability of Dkk-3 to inhibit tumorigenic potential of OS. Together, these data suggest that Dkk-3 has a negative impact on the progression of osteosarcoma. Reexpressing Dkk-3 in Dkk-3-deficient OS tumors may prove to be of benefit as a preventive or therapeutic strategy.
Assessment of Impacts Produced by Anthropogenic Sources in a Little City near an Important Industrial Area (Modugno, Southern Italy)
Authors: Amodio Martino , de Gennaro Gianluigi , Marzocca Annalisa , Trizio Livia , Tutino Maria
Published: February 2013

An annual monitoring campaign of VOCs, consisting of twelve sampling periods, was carried out from June 2008 to June 2009 in Modugno, a city located in the Apulia region (Southern Italy), in order to assess the urban air quality, identify the main emission sources, and quantify the cancer and no‐cancer risk attributable to inhalation exposures. Monitoring, carried out by using the Radiello diffusive samplers, was conducted in eleven sampling sites throughout the city taking into account the traffic density and the architecture of the city. From the study of the data, it was found that, among all considered VOCs, benzene, toluene, ethylbenzene, and xylenes (BTEX) are the pollutants at higher concentration. The analysis of VOC concentrations, the study of the topography of the city, and the use of different diagnostic ratios between the BTEX species showed that the vehicular traffic emissions were the predominant source of VOCs in the urban area of Modugno. Despite that the annual concentration of benzene is lower than the regulatory limit, the estimation of cancer risk showed that the global lifetime cancer risk attributed to the investigated VOC exposure was not negligible and therefore should be taken into account in future regulatory approaches.
A Proposal to Speed up the Computation of the Centroid of an Interval Type-2 Fuzzy Set
Authors: Celemin Carlos E. , Melgarejo Miguel A.
Published: February 2013

This paper presents two new algorithms that speed up the centroid computation of an interval type-2 fuzzy set. The algorithms include precomputation of the main operations and initialization based on the concept of uncertainty bounds. Simulations over different kinds of footprints of uncertainty reveal that the new algorithms achieve computation time reductions with respect to the Enhanced-Karnik algorithm, ranging from 40 to 70%. The results suggest that the initialization used in the new algorithms effectively reduces the number of iterations to compute the extreme points of the interval centroid while precomputation reduces the computational cost of each iteration.
A Fluorescent Sensor for Zinc Detection and Removal Based on Core‐Shell Functionalized Fe3O4@SiO2 Nanoparticles
Authors: Xu Yaohui , Zhou Yang , Ma Wenhui , Wang Shixing
Published: February 2013

The magnetic Fe3O4@SiO2 nanoparticles (NPs) functionalized with 8‐chloroacetylaminoquinoline as a fluorescent sensor for detection and removal of Zn2+ have been synthesized. The core‐shell structures of the nanoparticles and chemical composition have been confirmed by TEM, XRD, FTIR, and XPS techniques. The addition of functionalized Fe3O4@SiO2 NPs into the acetonitrile solution of Zn2+ had an effect of visual color change as well as significant fluorescent enhancement. High‐saturated magnetizations (24.7 emu/g) of functionalized Fe3O4@SiO2 NPs could help to separate the metal ions from the aqueous solution. The magnetic sensor exhibited high removal efficiency towards Zn2+ (92.37%). In this work, we provided an easy and efficient route to detect Zn2+ and simultaneously remove Zn2+.
A Rare Case of Segmental Clavicle Fracture in an Adolescent
Authors: Daolagupu Arup Kumar , Gogoi Parag Jyoti , Mudiganty Srikanth
Published: February 2013

Clavicular fractures commonly occur in adults and children. The usual mechanism of injury is a fall on the outstretched hand or direct trauma. The usual site of these fractures is the mid clavicle with lateral end and medial end clavicular fractures being less common, respectively. Segmental clavicular fractures have been reported in the literature; they usually occur at the medial and lateral ends and tend to occur in adults. Bipolar clavicular injuries involving medial and lateral ends have also been reported rarely but all in adults. We report a very rare case of segmental clavicular fracture involving the mid clavicle and lateral end in an adolescent caused by direct trauma. The management of segmental clavicle fractures has not been clearly outlined although operative intervention is indicated. We report the successful management of segmental fracture clavicle in an adolescent and discuss the relevant literature.