bluuebunny/crossref_metadata_2025 huggingface dataset:
Species delimitation and DNA barcoding of Atlantic Ensis (Bivalvia, Pharidae)
Authors: Vierna Joaquín , Cuperus Joël , Martínez‐Lage Andrés , Jansen Jeroen M. , Perina Alejandra , Van Pelt Hilde , González‐Tizón Ana M.
Published: September 2013

Ensis Schumacher, 1817 razor shells occur at both sides of the Atlantic and along the Pacific coasts of tropical west America, Peru, and Chile. Many of them are marketed in various regions. However, the absence of clear autapomorphies in the shell and the sympatric distributions of some species often prevent a correct identification of specimens. As a consequence, populations cannot be properly managed, and edible species are almost always mislabelled along the production chain. In this work, we studied whether the currently accepted Atlantic Ensis morphospecies are different evolutionary lineages, to clarify their taxonomic status and enable molecular identifications through DNA barcoding. For this, we studied 109 specimens sampled at 27 sites, which were identified as belonging to nine of those morphospecies. We analysed nucleotide variation at four nuclear (18S, 5.8S, ITS1, and ITS2) and two mitochondrial (COI and 16S) regions, although the 18S and 5.8S regions were not informative at the species level and were not further considered. The phylogenetic trees and networks obtained supported all morphospecies as separately evolving lineages. Phylogenetic trees recovered Ensis at each side of the Atlantic as reciprocally monophyletic. Remarkably, we confirm the co‐occurrence of the morphologically similar E. minor (Chenu, 1843) and E. siliqua (Linné, 1758) along the NW Iberian coast, a fact that has been often overlooked. In South America, a relevant divergence between E. macha (Molina, 1792) individuals from Chile and Argentina was unveiled and suggests incipient speciation. We also confirm the occurrence of the North American species E. directus (Conrad, 1843) as far south as north‐eastern Florida. Among the genomic regions analysed, we suggest COI as the most suitable DNA barcode for Atlantic Ensis. Our results will contribute to the conservation and management of Ensis populations and will enable reliable identifications of the edible species, even in the absence of the valves. The name Ensis coseli Vierna nom. nov. is proposed to replace E. minor Dall, 1899 non (Chenu, 1843).
HCN1 channels in cerebellar Purkinje cells promote late stages of learning and constrain synaptic inhibition
Authors: Rinaldi Arianna , Defterali Cagla , Mialot Antoine , Garden Derek L. F. , Beraneck Mathieu , Nolan Matthew F.
Published: September 2013

Key points

Purkinje cells in the cerebellum are important for motor learning and have electrical signalling properties determined by several different types of ion channel.

Using a restricted genetic deletion, we investigate the roles of HCN1 ion channels expressed by cerebellar Purkinje cells.

This deletion causes specific learning impairments in a subset of behaviours to which Purkinje cells contribute.

At a cellular level this specificity of function is mirrored by increases in the duration of responses to inhibitory synaptic input, without changes in responses to excitatory synaptic input activated in the absence of inhibition.

The results help us to understand how behaviours are influenced by ion channels important for aspects of computation in a defined neuronal cell type.

Abstract  Neural computations rely on ion channels that modify neuronal responses to synaptic inputs. While single cell recordings suggest diverse and neurone type‐specific computational functions for HCN1 channels, their behavioural roles in any single neurone type are not clear. Using a battery of behavioural assays, including analysis of motor learning in vestibulo‐ocular reflex and rotarod tests, we find that deletion of HCN1 channels from cerebellar Purkinje cells selectively impairs late stages of motor learning. Because deletion of HCN1 modifies only a subset of behaviours involving Purkinje cells, we asked whether the channel also has functional specificity at a cellular level. We find that HCN1 channels in cerebellar Purkinje cells reduce the duration of inhibitory synaptic responses but, in the absence of membrane hyperpolarization, do not affect responses to excitatory inputs. Our results indicate that manipulation of subthreshold computation in a single neurone type causes specific modifications to behaviour.
Sign‐preserving and sign‐inverting synaptic interactions between rod and cone photoreceptors in the dark‐adapted retina
Authors: Gao Fan , Pang Ji‐Jie , Wu Samuel M.
Published: September 2013

Key points

Five types of rods and cones in the dark‐adapted salamander retina are electrically coupled with linear and symmetrical junctional conductances Gj of different average values.

The average Gj values of the five types of rod–cone pairs recorded at day and night times suggest that the the circadian‐dependent changes in rod–cone coupling observed in the fish and rodent retinas are not present in the tiger salamander.

In addition to rod–cone coupling, there is a sign‐inverting, unidirectional rod→cone current IRC, and the current–voltage (IRC–VCone) relations are linear, with a reversal potential near the chloride reversal potential ECl.

I
RC can be observed in rods and cones separated by at least 260 μm, and its waveform resembles that of the rod‐elicited horizontal cell (HC) response IHC; a glutamate transporter‐associated chloride channel blocker TBOA suppresses IRC without affecting IHC.

These results suggest that IRC is largely mediated by HCs via a sign‐inverting feedback chemical synapse associated with a chloride channel in cones.

Abstract  We show that various types of rods and cones in the dark‐adapted salamander retina are electrically coupled with linear and symmetrical junctional conductances Gj (40–223 pS) and a rank order: RodC–large single cone, rod–large single cone, rod–small single cone, rod–accessory double cone and rod–principal double cone. By systematically comparing the transjunctional current–voltage (Ij–Vj) relations and average Gj values of the five types of rod–cone pairs recorded at day and night times, our results suggest that the differences in Gj values among various types of rod–cone pairs are not caused by circadian differences, and the circadian‐dependent changes in rod–cone coupling observed in the fish and rodent retinas are not present in the tiger salamander. In addition to rod–cone coupling, there is a sign‐inverting, unidirectional rod→cone current IRC, and the IRC–VCone relations are linear, with a reversal potential near the chloride reversal potential ECl. IRC can be observed in rods and cones separated by at least 260 μm, and its waveform resembles that of the rod‐elicited horizontal cell (HC) response IHC. A glutamate transporter‐associated chloride channel blocker TBOA suppresses IRC but not IHC. These results suggest that IRC is largely mediated by HCs via a sign‐inverting feedback chemical synapse associated with a chloride channel. IRC significantly reduced rod→cone coupling in the frequency range below 15 Hz, allowing better separation of rod and cone signals in the dark‐adapted retina.
Fault Tolerant Control of an Industrial Gas Turbine Based on a Hybrid Fuzzy Adaptive Unscented Kalman Filter
Authors: Mirzaee Amin , Salahshoor Karim
Published: September 2013

Gas turbines are generally used in power generation, the oil and gas industries, and as jet engines in aircrafts. Fault tolerance and reliability is important in such applications. Thus, accurate modeling and control system design is necessary. In this paper, first a nonlinear hybrid fuzzy model was developed for an industrial gas turbine, and then this model was used as the core of a fault tolerant control (FTC) system. The aforementioned model was trained by use of three months of operational data of a GE MS 5002 D gas turbine that is used for gas injection application, then it was fine tuned using expert knowledge and physical principles. A graphical user interface (GUI) was also developed to run various realistic operational scenarios of the gas turbine. The main point of the present work consists in introducing nonlinear fuzzy model schemes as the core of an adaptive unscented Kalman filter (AUKF) for fault diagnostic purposes. Analysis of the simulation results discloses that this FTC approach alleviates the effects of faults in two different scenarios such as sequential drift and bias in sensors/actuators and also in simultaneous faults that are a disastrous situation.
Statistical Characteristics of Fatigue Failure of Copper Thin Films
Authors: Jang Jae-Won , Hwangbo Yun , Kim Jae-Hyun , Lee Hak-Joo , Mag-isa Alexander E. , Lee Soon-Bok
Published: September 2013

Tension–tension fatigue tests were conducted on an electrodeposited copper film with a thickness of 12 μm under four levels of maximum stress and two levels of mean stress. Statistical characteristics of the measured fatigue lives were analyzed using three estimation methods for cumulative distribution function and five probability distributions in order to identify the dominant probability distribution for the fatigue life of copper film. It was found that while the 3-parameter Weibull distribution provided the best fit for the measured data in most cases, the other distributions also provide a similar coefficient of correlation for the fit. The absence of the dominant probability distribution was discussed with considerations of the deformation mode and the scanning electron microscope (SEM) measurements of fatigue-fractured surfaces. Based on the statistical analysis, the probabilistic stress-life (PSN) curves were obtained for statistical prediction of fatigue life of the copper film in the intermediate life regime.
Fabrication of GaN nanodots via GaN thermal decomposition in H2 atmosphere
Authors: Hui Xiong , Zhang Jin , Li Senlin , Wang Hu , Fang Yanyan , Dai Jiangnan , Chen Changqing
Published: September 2013

GaN nanodots were fabricated by thermal decomposition of GaN in H2 atmosphere at high temperatures. By varying annealing time and temperature, it was found that dot size and density were highly dependent on annealing conditions. Surface morphology of the sample indicates that the dot formation mechanism is chemical erosion under H2 flow. The etching proceeds in lateral directions, and the dots are formed in hexagonal pit areas. The fitted activation energy of GaN decomposition agrees well with the chemical properties of GaN in the experimental conditions.
Characterizing the modulation transfer function (MTF) of proton/carbon radiography using Monte Carlo simulations
Authors: Seco Joao , Oumano Michael , Depauw Nicolas , Dias Marta F. , Teixeira Rui P. , Spadea Maria F.
Published: September 2013

Purpose:

To characterize the modulation transfer function (MTF) of proton/carbon radiography using Monte Carlo simulations. To assess the spatial resolution of proton/carbon radiographic imaging.

Methods:

A phantom was specifically modeled with inserts composed of two materials with three different densities of bone and lung. The basic geometry of the phantom consists of cube‐shaped inserts placed in water. The thickness of the water, the thickness of the cubes, the depth of the cubes in the water, and the particle beam energy have all been varied and studied. There were two phantom thicknesses considered 20 and 28 cm. This represents an average patient thickness and a thicker sized patient. Radiographs were produced for proton beams at 230 and 330 MeV and for a carbon ion beam at 400 MeV per nucleon. The contrast‐to‐noise ratio (CNR) was evaluated at the interface of two materials on the radiographs, i.e., lung‐water and bone‐water. The variation in CNR at interface between lung‐water and bone‐water were study, where a sigmoidal fit was performed between the lower and the higher CNR values. The full width half‐maximum (FWHM) value was then obtained from the sigmoidal fit. Ultimately, spatial resolution was defined by the 10% point of the modulation‐transfer‐function (), in units of line‐pairs per mm (lp/mm).

Results:

For the 20 cm thick phantom, the FWHM values varied between 0.5 and 0.7 mm at the lung‐water and bone‐water interfaces, for the proton beam energies of 230 and 330 MeV and the 400 MeV/n carbon beam. For the 28 cm thick phantom, the FWHM values varied between 0.5 and 1.2 mm at the lung‐water and bone‐water interface for the same inserts and beam energies. For the 20 cm phantom the for lung‐water interface is 2.3, 2.4, and 2.8 lp/mm, respectively, for 230, 330, and 400 MeV/n beams. For the same 20 cm thick phantom but for the bone‐water interface the yielded 1.9, 2.3, and 2.7 lp/mm, respectively, for 230, 330, and 400 MeV/n beams. In the case of the thicker 28 cm phantom, the authors observed that at the lung‐water interface the is 1.6, 1.9, and 2.6 lp/mm, respectively, for 230, 330, and 400 MeV/n beams. While for the bone‐water interface the was 1.4, 1.9, and 2.9 lp/mm, respectively, for 230, 330, and 400 MeV/n beams.

Conclusions:

Carbon radiography (400 MeV/n) yielded best spatial resolution, with = 2.7 and 2.8 lp/mm, respectively, at the lung‐water and bone‐water interfaces. The spatial resolution of the 330 MeV proton beam was better than the 230 MeV proton, because higher incident proton energy suffer smaller deflections within the patient and thus yields better proton radiographic images. The authors also observed that submillimeter resolution can be obtained with both proton and carbon beams.
Enhancing Wnt Signaling in Rafts
Authors: VanHook Annalisa M.
Published: September 2013

A GPI-anchored protein promotes Wnt signaling by restricting Lrp6 phosphorylation to lipid rafts.
Postpartum spontaneous pneumomediastinum ‘Hamman's syndrome’
Authors: Kouki Sami , Fares Abd Allah
Published: September 2013

Spontaneous pneumomediastinum and subcutaneous emphysema (Hamman's syndrome) are rare but potentially dangerous complications of labour. The authors reported a case of a 23-year-old primigravida, admitted to our hospital for delivery after 40 weeks of pregnancy. She delivered a baby of 4.27 kg after 9 h from the start of labour. A few minutes after delivery, the patient developed dyspnoea and chest tightness, which made her doctor suspect pulmonary embolism. A chest X-ray and CT scan revealed pneumomediastinum and subcutaneous emphysema. The patient had been followed up for 3 days in our hospital, without specific therapy.
Complex sacral fracture
Authors: Alves José Luís , Duarte Nubélio , Rocha Armando , Frade Maria João
Published: September 2013

We reported a case of a patient with suspectedcauda equinasyndrome secondary to sacral fracture, after sustaining a fall. The difficulty in early diagnosis of complex sacral fractures and the lack of clearly defined guidelines for treatment are highlighted. Thorough clinical examination is mandatory, in order to make an adequate initial assessment and follow symptoms progression and response to treatment. The threshold for performing CT imaging (or MRI, if advised), when suspecting sacral fracture and neurological compromise, should be low. A multidisciplinary approach, with contributions from orthopaedic and/or neurosurgical surgery and physiatry, should be the gold standard of treatment. In this particular case, conservative management and close follow-up led to a significant improvement of problems and a good final outcome, showing that surgical decompression is not the only valid option and that further prospective studies are needed, regarding patient selection and timing of intervention.
Chronic low-dose aspirin use does not alter colonic mucosa in asymptomatic individuals: a prospective cross-sectional study (STROBE 1a)
Authors: Zagorowicz Edyta , Mroz Andrzej , Kraszewska Ewa , Rupinski Maciej , Kaminski Michal F , Regula Jaroslaw
Published: September 2013

Objectives

Aspirin may be involved in microscopic colitis (MC) development, but there are no data on colon histology in asymptomatic aspirin users. We prospectively assessed colonic and rectal mucosa from aspirin users, searching for MC features.

Methods

From colonoscopy screenees, two biopsy samples were taken from each of three locations: ascending colon, transverse colon and rectum. A pathologist measured chronicity of inflammation and activity indicators, epithelial cell height and subepithelial collagen layer width. Intraepithelial lymphocytes (IELs), intralaminal eosinophils and apoptotic cells/100 crypts were counted. Panel data models were used to analyse associations between aspirin use, biopsy location and microscopic parameters.

Results

Of 100 screenees (age: 40–65 years), 42 were current aspirin users. Median duration of aspirin usage was 48 months (range: 36–60) with dosage ranging from 75–325 mg/day. We observed reduced epithelium polymorphs in subjects who used aspirin for <48 months versus non-users (p=0.008). Paneth cell metaplasia was significantly less frequent in aspirin users versus non-users (p=0.006). Inflammatory cells in lamina propria (eosinophils) and epithelium (IELs) were most abundant in the ascending colon and decreased distally (ascending colon vs transverse colon and transverse colon vs rectum). Cryptitis was more frequent in the ascending colon vs the rectum.

Conclusions

We observed no specific MC features in asymptomatic chronic low-dose aspirin users. We found subtle physiological and histopathological differences between the bowel segments.
Vertical gradients in population characteristics of canopy lichens in boreal rainforests of Norway
Authors: Hilmo Olga , Gauslaa Yngvar , Rocha Lester , Lindmo Sigrid , Holien Håkon
Published: September 2013

All specimens of three foliose lichens (Lobaria pulmonaria (L.) Hoffm., n = 725; Lobaria scrobiculata (Scop.) DC., n = 6613; Pseudocyphellaria crocata (L.) Vain., n = 1237) and two pendulous lichens (Alectoria sarmentosa (Ach.) Ach., n = 441; Ramalina thrausta (Ach.) Nyl., n = 990) were collected from 160 random Picea abies (L.) H. Karst. branches (2–15 m above the ground) in three spruce-dominated boreal rainforests in Norway. Maximum diameter (foliose lichens), length (pendulous lichens), and reproductive structures were quantified in each thallus. The effects of measured tree and branch variables on abundance and reproduction were tested by generalized linear mixed models with binomial errors (binomial GLMM) and zero-altered (over-dispersed) Poisson generalized linear mixed models (ZAPGLMM). Lobaria pulmonaria, P. crocata, and R. thrausta occurred predominantly in the lower canopy, whereas the remaining species were also common at higher levels. The portions of thalli producing soredia and (or) isidia were 60%, 22%, and 14% for P. crocata, L. scrobiculata, and L. pulmonaria, respectively. Isidiate and (or) sorediate L. pulmonaria thalli occurred mainly on low, dead branches, whereas sorediate L. scrobiculata and P. crocata occurred at all heights. The occurrence of small P. crocata, <5 mm, decreased by branch height and small L. scrobiculata, <5 mm, increased with branch length and decreased with tree age. Upper branches supported a significant part of the total populations of studied lichens and are, thus, important when evaluating epiphyte conservation status.
A simulation-based approach to assess sensitivity and robustness of fisheries management indicators for the pelagic fishery in the Bay of Biscay
Authors: Lehuta Sigrid , Mahévas Stéphanie , Le Floc’h Pascal , Petitgas Pierre
Published: September 2013

Indicators are widely promoted as means to monitor ecosystem status or to evaluate fisheries management performance. “Which indicators are most relevant as decision-support tools in fisheries management?” still remains a topical question. Indicators should be metrics related to fish populations and fleets and should be sensitive to management strategies. However, given the complexity of the processes involved, it is often difficult to unequivocally interpret variations in metrics. A simulation approach was used to study metric properties and to identify robust and relevant fishery indicators. By applying sensitivity analysis methods, simulation designs were built that cross a variety of management scenarios and uncertainty hypotheses. Bio-economic outputs were simulated using a mechanistic model (ISIS-Fish), and their properties were statistically analyzed. This approach was applied to the pelagic fishery of the Bay of Biscay. The analysis of metric properties highlighted the major factors driving variations in each metric and identified the important sources of uncertainty that need to be reduced to allow the use of metrics as indicators. Although very few metrics gave robust indications of management performance, sensitivity indices evidenced how management performances could be improved, and spatially disaggregated metrics provided insights into the mechanisms underlying management performance.
Atypical antipsychotics such as risperidone, but not paliperidone, worsen vascular endothelial function via upregulation of adhesion molecules VCAM-1, ICAM-1, and E-selectin in diabetic rats
Authors: Aboul-Fotouh Sawsan , Elgayar Nesreen
Published: September 2013

Schizophrenia doubles the odds of diabetes, and atypical antipsychotics (AAPs) also increase risk of diabetes. Indeed, little is known about the effects of AAPs on vascular dysfunctions associated with diabetes. This study aimed to determine the effects of risperidone (RISP) and paliperidone (PALI) on the vascular function of diabetic rats. Diabetes was induced by feeding with a high-fat diet followed by the administration of streptozotocin (35 mg·(kg body mass)−1, by intraperitoneal injection). Rats received RISP or PALI (1.25 mg·kg−1·d−1, per os) for 3 weeks. Endothelium-dependent relaxation, systolic blood pressure, lipid profile, insulin resistance, and adhesion molecules, vascular cell-adhesion-molecule-1 (VCAM-1), intracellular-adhesion-molecule-1 (ICAM-1), and E-selectin were investigated. RISP significantly worsened the impaired endothelium-dependent relaxation of diabetic aortic rings with upregulation of the adhesion molecules VCAM-1, ICAM-1, and E-selectin, and proinflammatory cytokines MPC-1 and TNF-α. RISP augmented the metabolic dysfunctions and reduced insulin sensitivity in the insulin tolerance test as well as HOMA–IR. PALI produced insignificant effects on vascular and metabolic aberrations. Our results suggest that RISP, but not PALI, aggravates the metabolic abnormalities and vascular dysfunction associated with diabetes, which may be mediated by upregulation of VCAM-1, ICAM-1, and E-selectin. Nevertheless, future investigation for the possible mechanisms underlying the difference noticed between the 2 AAPs is warranted.
Grape seed and skin extract mitigates heart and liver oxidative damage induced by a high-fat diet in the rat: gender dependency
Authors: Charradi Kamel , Mahmoudi Mohamed , Elkahoui Salem , Limam Ferid , Aouani Ezzedine
Published: September 2013

Obesity is a public health problem contributing to morbidity and mortality from metabolic syndrome. It has long been recognized that there is a gender dependency in several obesity-related health risks. Using a high fat diet (HFD) to induce obesity in Wistar rats, we studied the gender dependency of fat-induced oxidative stress in the heart and liver, with a special emphasis on the distribution of transition metals, as well as the protective effects of grape seed and skin extract (GSSE). HFD induced obesity in both male and female rats, characterized by increased body weight as well as relative liver mass in both genders, and increased relative heart mass in the males only. HFD also provoked the accumulation of triglycerides and total cholesterol into the male hearts, and into the livers of both genders. HFD induced oxidative stress in the male hearts and also in the livers of both genders. Furthermore, HFD affected cardiac levels of copper in the males, and hepatic levels of copper and zinc in both genders, whereas HFD affected free iron in the male hearts and female livers, specifically. In conclusion, HFD treatment altered transition metal homeostasis more drastically in the male heart than in the female liver, and GSSE efficiently protected these organs against fat-induced disturbances, regardless of gender.
Sexual dimorphism in an under-ice spawning fish: the burbot (Lota lota)
Authors: Cott P.A. , Johnston T.A. , Gunn J.M.
Published: September 2013

Sexual dimorphic characteristics arise in response to differing selective pressures on the sexes and can be used to attract mates or signal reproductive readiness. How sexual dimorphism is expressed where visual cues may be of limited use is an underexplored aspect of reproductive ecology. The burbot (Lota lota (L., 1758)) is a common boreal fish that is not overtly sexually dimorphic. It spawns mid-winter in a light-limited under-ice environment. We examined a variety of morphological and reproductive characteristics in burbot from a northern lake over one full year to assess both seasonal and sex-based variation. Spawning occurred under ice in early February. Seasonal variation was more pronounced in females for many of the traits examined. Growth, fin lengths, swim bladder mass, and liver lipid concentration did not differ between the sexes. Male burbot had significantly higher body condition, larger gas glands, and smaller livers. Males also had significantly larger gonads than females, unusual for boreal fishes. The high gonadal investment of male burbot suggests that sperm competition may be intense in this species. This study demonstrates that sexual dimorphism can be subtle and is present in a seemingly monomorphic species—the burbot.
FUNCTIONAL INTEGRAL REPRESENTATIONS AND GOLDEN–THOMPSON INEQUALITIES IN BOSON–FERMION SYSTEMS
Authors: ARAI ASAO
Published: September 2013

For a general class of boson–fermion Hamiltonians H acting in the tensor product Hilbert space L2(ℝn) ⊗ ∧(ℂr) of L2(ℝn) and the fermion Fock space ∧(ℂr) over ℂr(n, r ∈ ℕ), we establish, in terms of an n-dimensional conditional oscillator measure, a functional integral representation for the trace Tr (F ⊗ zN f e-tH)(F ∈ L∞(ℝn), z ∈ ℂ∖{0}, t > 0), where N f is the fermion number operator on ∧(ℂr). We prove a Golden–Thompson type inequality for | Tr (F ⊗ zN f e-tH)|. Also we discuss applications to a model in supersymmetric quantum mechanics and present an improved version of the Golden–Thompson inequality in supersymmetric quantum mechanics given by Klimek and Lesniewski ([Lett. Math. Phys.21 (1991) 237–244]). An upper bound for the number of the supersymmetric states is given as well as a sufficient condition for the spontaneous supersymmetry breaking. Moreover, we derive a functional integral representation for the analytical index of a Dirac type operator on ℝn (Witten index) associated with the supersymmetric quantum mechanical model.
EFFECTS ON MECHANICAL PROPERTIES OF REFRACTORY METAL DOPED Ti3Al ALLOY
Authors: ZHANG CHUAN-HUI , HUANG SHUO , LI RUI-ZI , SHEN JIANG , CHEN NAN-XIAN
Published: September 2013

The elastic constants and the mechanical properties of doped Ti 3 Al alloys are studied by using embedded-atom method. The calculated formation enthalpies and volumes of some Ti 75-x Al 25-y M x+y( M = V , Nb and Ta ) decrease with increasing the additional concentrations. The effects of mechanical properties are different by doping different elements. As a result, small amounts of doping Nb and Ta elements would reduce the fracture of Ti 3 Al alloy; while Nb and Ta doping into Ti sites would improves the hardness. Most doped Ti 3 Al are good ductile materials and the alloying elements Nb and Ta significant decrease the brittleness. Our results consist with the experiments.
KERNEL-BASED 2D FISHER DISCRIMINANT ANALYSIS WITH PARAMETER OPTIMIZATION FOR FACE RECOGNITION
Authors: LIU XIAO-ZHANG , WANG PATRICK S. P. , FENG GUO-CAN
Published: September 2013

As is known, kernel methods are developed to handle nonlinear classification. However, we have found that based on vector representation of face images, it is not easy to improve the performance of LDA-based methods by incorporating the kernel trick. Actually, in the case that the dimensionality of face images in vector form is far greater than the number of samples, linear classifiers are adequate and it is illogical to increase dimensions of vectors using kernel methods. In order to give full play to the strong point of the kernel technique for manipulating the nonlinearity of pattern distribution, we propose a new image feature extraction method for face recognition, called kernel-based two-dimensional Fisher discriminant analysis (K2DFDA), which deals with a face image directly as a matrix, instead of a stacked vector from rows or columns of the image. Moreover, we present a kernel parameter optimization scheme for K2DFDA, based on the maximum margin criterion and the damped Newton's method. Experimental results show the effectiveness of K2DFDA and its parameter optimization scheme.
COSMIC ACCELERATION AND CONCORDANCE FROM CAUSAL BACKREACTION WITH RECURSIVE NONLINEARITIES
Authors: BOCHNER BRETT
Published: September 2013

We review the causal backreaction paradigm, in which the need for Dark Energy is eliminated via the generation of an apparent cosmic acceleration from the causal flow of inhomogeneity information coming in from distant structure-forming regions. The formalism detailed here incorporates the effects of "recursive nonlinearities": the process by which already-established metric perturbations will subsequently act to slow-down all future flows of inhomogeneity information. Despite such effects, we find viable cosmological models in which causal backreaction successfully serves as a replacement for Dark Energy, via the adoption of relatively large values for the dimensionless "strength" of the clustering evolution functions being modeled. These large values are justified by the hierarchical nature of clustering and virialization in the universe, which occurs on multiple cosmic length scales simultaneously; moreover, the clustering model amplitudes needed to match the apparent acceleration can be moderated via the incorporation of a model parameter representing the late-time slow-down of clustering due to astrophysical feedback processes. In summary, an alternative cosmic concordance can be achieved for a matter-only universe in which the apparent acceleration observed is generated entirely by causal backreaction effects. Lastly, considering the long-term fate of the universe, while the possibility of an "eternal" acceleration due to causal backreaction seems unlikely, this conclusion does not take into account the large-scale breakdown of cosmological isotropy in the far future, or the eventual ubiquity of gravitationally-nonlinear perturbations.
HYBRID MODIFIED GRAVITY UNIFYING LOCAL TESTS, GALACTIC DYNAMICS AND LATE-TIME COSMIC ACCELERATION
Authors: CAPOZZIELLO SALVATORE , HARKO TIBERIU , LOBO FRANCISCO S. N. , OLMO GONZALO J.
Published: September 2013

The nonequivalence between the metric and Palatini formalisms of f(R) gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric Einstein–Hilbert Lagrangian with an [Formula: see text] term constructed à la Palatini, the "true" gravitational field is described by the interpolation of these two nonequivalent approaches. The theory predicts the existence of a light long-range scalar field, which passes the local constraints and affects the galactic and cosmological dynamics. Thus, the theory opens new possibilities for a unified approach, in the same theoretical framework, to the problems of dark energy and dark matter, without distinguishing a priori matter and geometric sources, but taking their dynamics into account under the same standard.
PREPARATION OF NICKEL OXIDE EMBEDDED SELF ORGANIZED TITANIA NANOTUBES ARRAY BY NEW ALGINATE METHOD AS A SUPERCAPACITOR ELECTRODE
Authors: DABAGHI HABIBEH HADAD , KAZEMZAD MAHMOOD , GANJKHANLOU YADOLAH , ESKANDARI RAHMATOLLAH
Published: September 2013

Potentiostatic two step anodizing of titanium utilized for preparation of self organized titania nanotubes arrays with diameter of 150 nm. Then the new alginate method has been applied for incorporation of NiO into the nanotubes. The prepared hybrid materials have been characterized by various methods including field emission scanning electron microscopy, X-ray diffractometry and cyclic voltammetry analyses. The X-ray diffraction patterns of samples were also studied by Rietveld's method. Results showed that the prepared electrode containing anatase, rutile and NiO phases with fraction of 70, 8, and 22%, respectively. It was found that by application of the new method, porous NiO uniformly coated on nanotubes surface and great enhancement of specific capacitance from 0.14 to 3.8 mF cm-2could be obtained. The prepared nanocomposites are promising materials for supercapacitance application and also for solar energy harvesting systems.
AN IMPROVED ANALYTICAL METHOD FOR RESTRAINED RC STRUCTURES SUBJECTED TO STATIC AND DYNAMIC LOADS
Authors: CHEN LI , FANG QIN , GUO ZHIKUN , LIU JINCHUN
Published: September 2013

Once a RC structure is laterally restrained, both the static and dynamic load resistances will be enhanced due to the membrane action. Despite this known advantage, the apparent lack of systemic and efficient methods of analysis poses a drawback in the design and assessment of blast-resistant RC structures. First, a simplified membrane action theory was presented by modifying the maximum membrane force design method (MMFM) for predicting the total static resistance-deflection curves of restrained beam-slab RC structures. Second, a series of constrained beams were tested to validate the new theory, for which better agreement was observed between the test data, the results predicted by the proposed theory and those by MMFM. The results show that the static load carrying capacity and membrane force increase with increasing restraint stiffness, and the smaller the reinforcement ratio is, the larger the load carrying capacity increases. Third, based on the improved compressive static membrane action theory, a new analytical method was developed to investigate the dynamic responses of restrained RC structures subjected to blast loads, using an equivalent single degree of freedom system that combines the three-parameter elasto-viscoplastic rate-sensitive material model with the proposed static theory. Good agreement is observed between the test data and the analytical results. Finally, it is demonstrated that the dynamic resistance capacity increases with increasing load rate and restraint stiffness and with decreasing tensile reinforcement ratio, but the larger the dynamic resistance is, the larger the plastic deformation of the structure.
TEST RANK OF THE LIE ALGEBRA F/[R′, F]
Authors: ÖĞÜŞLÜ NAZAR ŞAHİN
Published: September 2013

Let F be a free Lie algebra of rank n ≥ 2 and R be a fully invariant ideal of F. We show that the test rank of the Lie algebra F/[R′, F] is equal to 1 when n is even and less than or equal to 2 when n is odd.
Conformal gravity with electrodynamics for fermion fields and their symmetry breaking mechanism
Authors: Fabbri Luca
Published: September 2013

In this paper, we consider an axial torsion to build metric-compatible connections in conformal gravity, with gauge potentials; the geometric background is filled with Dirac spinors: scalar fields with suitable potentials are added eventually. The system of field equations is worked out to have torsional effects converted into spinorial self-interactions: the massless spinors display self-interactions of a specific form that gives them the features they have in the non-conformal theory but with the additional character of renormalizability, and the mechanisms of generation of mass and cosmological constants become dynamical. As a final step we will address the cosmological constant problem and the coincidence issue.
DECOUPLING FROM STANDARDS — PROCESS MANAGEMENT AND TECHNICAL INNOVATION IN SOFTWARE DEVELOPMENT ORGANISATIONS
Authors: FRIED ANDREA , GEY RONNY , PRETORIUS AGNIETA , GÜNTHER LARS
Published: September 2013

The paper explores process management standards in software development organisations. It centres on the question how organisations manage the compliance with process standards as well as the need for ongoing technical innovation at the same time. It refers to former studies where it was concluded that process management standards tend to crowd out technical innovations in organisations. By reconsidering the coupling approach of Orton and Weick (1990) we show based on four case studies that it does not apply to those organisations which allow innovating activities being loosely coupled or decoupled from the reigning standard script. These organisations sustain their chances for incremental and fundamental technical innovations. Dealing with loosely coupled or decoupled innovating activities implies a dialectical standard management. It means that potentially contradictory and conflict-ridden activities like standardised practices and innovating activities are manageable by specific institutional, temporarily limited and formal/informal solutions. Furthermore, we scrutinise in this paper the decoupling discussion of some parts of the standard management literature. Standard decoupling is often seen as an unfortunate, but necessary solution to cope with external pressure for internal standardisation. In contrast to this, we develop an understanding where standard decoupling is not defined as a set of activities without affecting the 'technical core' of an organisation. (Brunsson and Jacobsson, 2000b; Meyer and Rowan, 1967). Rather, decoupling is seen as a temporary and locally limited situation of an innovating subsystem within an organisation where it is allowed to detach from reigning standardised practices and to test and develop innovative ideas under less formalised conditions.
THEORETICAL STUDY OF THE ADSORPTION AND DIFFUSION OF OXYGEN ATOM ONO-TERMINATEDZnO$(000\bar 1)$ SURFACE
Authors: QIAO LIANG , ZENG YI , QU CHAOQUN , HU XIAOYING , SONG LIJUN , LIU SHUJIE , SUI YONGMING
Published: September 2013

The adsorption and diffusion of oxygen atom on the O -terminated ZnO [Formula: see text] surface have been systematically investigated based on first-principles density functional theory. The results show that the surface relaxation of the ZnO [Formula: see text] surface is significant. In the view of the maximization of the adsorption energy, the preferred site for the adsorption of oxygen atom is the top- O site above the oxygen atom of the first Zn – O bilayer. There is chemical bond formed between the adsorbed oxygen atom and the oxygen atom on the surface, which will result in the redistribution of the charges. The charges transfer from the ZnO surface to the adsorbed oxygen atom, which will heighten the surface potential of ZnO surface and increase the surface work function. Moreover, the diffusion of the oxygen atom on the ZnO surface has also been investigated, and the potential barriers of the diffusion have been identified to reveal the adsorption stability.
MAPPING ASPERITIES ALONG THE SAGAING FAULT ZONE, MYANMAR USING b-VALUE ANOMALIES
Authors: PAILOPLEE SANTI
Published: September 2013

In this study, the b-values of frequency-magnitude earthquake distributions were mapped spatially along the sagaing fault zone (SFZ), central Myanmar. Three sub-datasets of the complete earthquake catalogue were tested in order to ensure the applied assumption. Using the present-day dataset (1980–2010), two areas of low b-values, which are prospective potential earthquake sources, were identified at the Naypyidaw-Mandalay and southwestern part of Myitkyina in the central and northern part of the SFZ, respectively. To assess the possible earthquake magnitudes, the b-values were mapped in the cross-section dimension along the SFZ. The obtained areas of low b-values, referred to as the fault asperity regions, conformed to those illustrated in the surface map. The asperity's sizes, examined from specific low b-values of ≤ 0.65 and ≤ 0.060 were quantitatively estimated and empirically converted to the potential earthquake magnitudes. This analysis revealed three prospective areas surrounding the Myitkyina regions capable of generating earthquakes in the future with a possible magnitude of 8.6 Richter. The contribution of effective mitigation plans are, therefore, urgently needed for Myanmar and the adjacent area.
THE MEDIAN FUNCTION ON TREES
Authors: ORTEGA OSCAR , KRISTON G.
Published: September 2013

A median of a sequence π = (x1, x2, …, xk) of elements of a finite metric space (X, d) is an element x for which [Formula: see text] is minimum. The function with domain the set of all finite sequences on X and defined by Med(π) = {x | x is a median of π} is called the Median function on X. In this note, an axiomatic characterization of the median function on finite trees is given.
Does Treewidth Help in Modal Satisfiability?
Authors: Praveen M.
Published: September 2013

Many tractable algorithms for solving the Constraint Satisfaction Problem (
Csp
) have been developed using the notion of the treewidth of some graph derived from the input
Csp
instance. In particular, the
incidence graph
of the
Csp
instance is one such graph. We introduce the notion of an incidence graph for modal logic formulas in a certain normal form. We investigate the parameterized complexity of modal satisfiability with the modal depth of the formula and the treewidth of the incidence graph as parameters. For various combinations of Euclidean, reflexive, symmetric, and transitive models, we show either that modal satisfiability is Fixed Parameter Tractable (
Fpt
), or that it is W[1]-hard. In particular, modal satisfiability in general models is
Fpt
, while it is W[1]-hard in transitive models. As might be expected, modal satisfiability in transitive and Euclidean models is
Fpt
.
A framework for acquisition and application of software architecture evolution knowledge
Authors: Ahmad Aakash , Jamshidi Pooyan , Pahl Claus
Published: September 2013

Software systems continuously evolve as a consequence of frequent changes in their functional requirements and the environment surrounding them. Architecture-centric software evolution (ACSE) enables changes in software structure and behaviour while abstracting the complex implementation-specific details. However, due to recurring evolution there is a need for solutions that enable a systematic reuse of frequent changes in software architectures. In recent years, architecture change patterns and evolution styles proved successful in promoting reuse expertise to tackle architecture evolution. However, there do not exist any solutions that enable a continuous
acquisition and application
of architecture evolution knowledge to systematically address frequent changes in software architectures. In this paper, we propose a framework
PatEvol
that aims to unify the concepts of i) software repository mining and ii) software evolution to enable acquisition and application of architecture evolution knowledge. In the proposed
PatEvol
framework, we present knowledge acquisition (
architecture evolution mining
) to enable post-mortem analysis of evolution histories to empirically discover evolution-centric knowledge. Furthermore, we support reuse of discovered knowledge to enable knowledge application (
architecture evolution execution
) that enables evolution-off-the-shelf in software architectures. Tool support facilitates the knowledge acquisition and knowledge application processes in the
PatEvol
framework.
Data rate based adaptive thread assignment solution for combating the SlowPOST denial of service attack
Authors: Raghunath Amritha , Ramachandran Sadhana , Subramanian Selvakumar , Vaidyanathan Sreevatsan
Published: September 2013

Denial of Service (DoS) attacks represent a major threat to network security, especially in today's networked world. There has been significant research in this area, primarily focused on mitigating and preventing DoS attacks affecting transport layer services. This paper addresses issues arising from a new variation of a DoS attack, namely the SlowPOST attack that affects Application Layer services. In SlowPOST, the malicious clients send data at a slow rate after the connection is established, and the server is left waiting for the data to arrive. These attacks are particularly devastating due to their ability to resist detection due to their protocol compliance. In addition, such attacks do not require the massive resources that DoS attacks normally require, making them easier to launch. Some solutions for this issue have already been deployed in some commercial servers. These solutions are based on either monitoring traffic or enforcing a time limit on the transmission of the protocol headers. In order to achieve reliable detection, the detection parameters need to adapt to the constantly changing traffic. This paper proposes a novel algorithm that uses the data rate of connections to evolve a threshold for determining potential attackers in SlowPOST. This proposed method is tested by subjecting a server to an attack, and it was observed that in the absence of this method, the servicing of legitimate requests is not completed.
A novel fuzzy based approach for effort estimation in software development
Authors: Sinhal Amit , Verma Bhupendra
Published: September 2013

Accurate and credible software effort estimation is always a challenge for academic research and software industry. In the beginning, estimation was carried out using only human expertise or algorithmic models, but more recently, interest has turned to a range of Soft Computing techniques. New paradigms such as Fuzzy Logic enable a choice for software effort estimation. Constructive Cost Model (COCOMO) is considered to be the most widely used model for effort estimation. Effort drivers have immense influence on COCOMO and this paper investigates the role of cost drivers (effort features) in improving the precision of effort estimation using Fuzzy Logic. Fuzzy logic-based estimation models are more appropriate when indistinct and incorrect information is to be used. This paper aims at estimating effort in an efficient way using a Fuzzy technique. For this purpose, the COCOMO81 dataset and the Fuzzy Inference System (FIS) of MATLAB are used for implementation. At the end, the outcomes are compared against traditional methods using parameters like Mean Magnitude of Relative Error (MMRE) and Pred (25).
Research challenges in large-scale agile software development
Authors: Dingsøyr Torgeir , Moe Nils Brede
Published: September 2013

Agile software development methods are increasingly used in large-scale software development. This article summarizes some of the discussion on research challenges in large-scale agile development at a workshop at the International Conference on Agile Software Development (XP2013), in the form of a research agenda.
Views on software engineering from the twin peaks of requirements and architecture
Authors: Galster Matthias , Mirakhorli Mehdi , Cleland-Huang Jane , Burge Janet E. , Franch Xavier , Roshandel Roshanak , Avgeriou Paris
Published: September 2013

The disciplines of requirements engineering (RE) and software architecture (SA) are fundamental to the success of software projects. Even though RE and SA are often considered in isolation, drawing a line between RE and SA is neither feasible nor reasonable as requirements and architectural design impact each other. This observation motivated the Twin Peaks model that was the subject of the Second International Workshop on the Twin Peaks of Requirements and Architecture (TwinPeaks@ICSE 2013). TwinPeaks@ICSE 2013 was held in conjunction with the 35th International Conference on Software Engineering 2013 in San Francisco, CA. The workshop aimed at providing a forum for researchers, practitioners and educators from the areas of RE and SA to discuss their experiences, forge new collaborations, and explore innovative solutions that address the challenges that occur when relating RE and SA. The workshop provided participants with an opportunity to become familiar with the relationship between RE and SA in the broader context of software engineering, rather than in an isolated context of either RE or SA. The workshop featured one industrial keynote, five research paper presentations, two invited talks and four working group discussions.