Discontinuous Research Articles

Survey of the main causal agents of fusarium head blight of durum wheat around Bologna, northern Italy

Several Fusarium species and Microdochium nivale are involved in fusarium head blight (FHB), which in Italy has been constantly present on wheat since 1995. This study was carried out from 1995 to 2007 on FHB-infected durum wheat heads collected in the Bologna countryside, Emilia-Romagna, northern Italy. The most frequent Fusarium species found were: Fusarium graminearum (32.1%), F. culmorum (25.2%) and F. poae (17.8%), while F. avenaceum and M. nivale occurred discontinuously. Other Fusarium species were also found, but only sporadically. It is important to identify and characterize the main species involved in the FHB syndrome for this will help us to establish control strategies that will contain the disease and the content of mycotoxins in food and animal feed.

CYCLICAL CHANGES IN THE TIMING RESIDUALS FROM THE PULSAR B0919+06

We report the detection of a large glitch in the pulsar B0919+06 (J0922+0638). The glitch occurred in 2009 November 5 (MJD 55140) and was characterized by a fractional increase in the rotation frequency of Deltanu/nu=1.3x10^{-6}. A large glitch happens in the pulsar whose rotation has unstable character. We present the results of the analysis of the rotation behavior of this pulsar over the 30-year time span from 1979 to 2009. These results show that the pulsar's rotation frequency underwent continuous, slow oscillations which look like glitch-like events. During the 1991-2009 interval, the pulsar experienced a continuous sequence of 12 slow glitches with a fractional increase in the rotation frequency Deltanu/nu=1.5x10^{-9}. All the slow glitches observed have a similar signature related to a slow increase in the rotation frequency during 200 days and the subsequent relaxation back to the pre-glitch value during 400 days. We show that a continuous sequence of such slow glitches is characterized by practically identical amplitudes equal to Deltanu=3.5x10^{-9} Hz and identical time intervals between glitches of about 600 days and is well described by a periodic sawtooth-like function. The detection of two different phenomena, such as a large glitch and a sequence of slow glitches, indicates the presence of two types of discontinuities in the rotation frequency of the pulsar B0919+06. These discontinuities can be classified as normal and slow glitches.

Method of multiple references for 3D imaging with Fourier transform interferometry

This letter presents an improved phase referencing technique, called Method of Multiple References, for optical profilometry. Based on a lookup table, the method eliminates several major drawbacks of single-reference Fourier Transform Interferometry by enabling surface error correction for steep slopes and step discontinuities, and by allowing mapping of multiple discrete objects using a single image set. The algorithm is tested using a fiber optic coupler-based FTI system and shown to have RMS surface error less than 0.03 mm.

A Smooth Finite Element Method Based on Reproducing Kernel DMS-Splines

The element-based piecewise smooth functional approximation in the conventional finite element method (FEM) results in discontinuous first and higher order derivatives across element boundaries Despite the significant advantages of the FEM in modelling complicated geometries, a motivation in developing mesh-free methods has been the ease with which higher order globally smooth shape functions can be derived via the reproduction of polynomials There is thus a case for combining these advantages in a so-called hybrid scheme or a `smooth FEM' that, whilst retaining the popular mesh-based discretization, obtains shape functions with uniform C-p (p >= 1) continuity One such recent attempt, a NURBS based parametric bridging method (Shaw et al 2008b), uses polynomial reproducing, tensor-product non-uniform rational B-splines (NURBS) over a typical FE mesh and relies upon a (possibly piecewise) bijective geometric map between the physical domain and a rectangular (cuboidal) parametric domain The present work aims at a significant extension and improvement of this concept by replacing NURBS with DMS-splines (say, of degree n > 0) that are defined over triangles and provide Cn-1 continuity across the triangle edges This relieves the need for a geometric map that could precipitate ill-conditioning of the discretized equations Delaunay triangulation is used to discretize the physical domain and shape functions are constructed via the polynomial reproduction condition, which quite remarkably relieves the solution of its sensitive dependence on the selected knotsets Derivatives of shape functions are also constructed based on the principle of reproduction of derivatives of polynomials (Shaw and Roy 2008a) Within the present scheme, the triangles also serve as background integration cells in weak formulations thereby overcoming non-conformability issues Numerical examples involving the evaluation of derivatives of targeted functions up to the fourth order and applications of the method to a few boundary value problems of general interest in solid mechanics over (non-simply connected) bounded domains in 2D are presented towards the end of the paper

3D Goussev filter—a signal separation and edge detection filter applied to aeromagnetic data in the Great Australian Bight

A phase of image processing usually precedes the initial stages of any interpretation project. With aeromagnetic data, this image processing involves the construction of a variety of derivative grids of the total magnetic intensity data to enhance the magnetic signal and make it ready for interpretation. Routinely, the reduction-to-the-pole (RTP) transform is performed on the total magnetic intensity (TMI) data and then the first and, possibly, second vertical derivative calculations to enhance the magnetic signal. The first vertical derivative (1VD) of the RTP data is the most common derivative filter to enhance the magnetic signal to allow anomalies generated by structure and boundaries to become more evident. The tilt derivative is an excellent edge-detection filter (Miller and Singh, 1994; Fairhead et al., 2004). The Goussev filter (Goussev et al., 1998, 2003; Nabighian et al., 2005) provides high signal-to-noise ratio and high lateral resolution of magnetic anomalies from different types of structural discontinuities. These more complex filters are often applied on aeromagnetic data to produce enhanced imagery for interpretation and then compared to the RTP 1VD grid to see where they can add value to the interpretation process.

Directional Derivatives of Oblique Reflection Maps

Given an oblique reflection map Γ and functions [Formula: see text] (the space of ℝK-valued functions that have finite left and right limits at every point), the directional derivative [Formula: see text] of Γ along χ, evaluated at ψ, is defined to be the pointwise limit, as [Formula: see text], of the family of functions [Formula: see text]. Directional derivatives are shown to exist and lie in [Formula: see text] for oblique reflection maps associated with reflection matrices of the so-called Harrison-Reiman class. When ψ and χ are continuous, the convergence of [Formula: see text] to [Formula: see text] is shown to be uniform on compact subsets of continuity points of the limit [Formula: see text], and the derivative [Formula: see text] is shown to have an autonomous characterization as the unique fixed point of an associated map. Directional derivatives arise as functional central limit approximations to time-inhomogeneous queueing networks. In this case ψ and χ correspond, respectively, to the functional strong law of large numbers and functional central limits of the so-called netput process. In this work it is also shown how the various types of discontinuities of the derivative [Formula: see text] are related to the reflection matrix and properties of the function Γ(ψ). In the queueing network context, this describes the influence of the topology of the network and the states (of underloading, overloading, or criticality) of the various queues in the network on the discontinuities of the directional derivative. Directional derivatives have also been found useful for identifying optimal controls for fluid approximations of time-inhomogoeneous queueing networks and are also of relevance to the study of differentiability of stochastic flows of obliquely reflected Brownian motions.

Evaluation of contrast-enhanced transrectal ultrasound in differential diagnosis of prostate cancer and benign prostatic hyperplasia

Objective To evaluate the application of contrast-enhanced transrectal ultrasound ( CETRUS) to identify prostate cancer(PCa) from benign prostatic hyperplasia(BPH). Methods A total of 86 patients with focal prostatic disease detected by trans rectal ultrasound(TRUS) were enrolled in this study.Each patient underwent grey-scale TRUS, CE-TRUS, and targeted-biopsy of prostateunder ultrasound guidance successively on the same day. The criteria of perfusion pattern would be statistically analyzed among groups divided by pathological findings. Every patient's images of CE-TRUS were observed and features of perfusion pattern were recorded by two doctors who were blind to any clinical data of patient.Then these features recorded by two doctors were compared, if the features were coherent, they would be recorded as final results,and otherwise two doctors would consult till the features were coherent. Results Compared with BPH group, the enhancement features of PCa group were rapid enhancement, increased enhancement, heterogeneous enhancement, well-defined boundary of lesion after enhancement, asymmetric appearance of intraprostatic vessels, rapid decrease, perfusion defect areas within lesions and the roughly discontinuous juncture between enhancement and no enhancement area within lesions. Conclusions There was significant difference in enhancement pattern between BPH and PCa groups, observing enhancement pattern could help to identify prostate cancer from benign prostate hyperplasia. Key words: Ultrasonography; Microbubbles; Prostatic neoplasms; Prostatic hyperplasia

Experimental study on prevention and treatment of Helicobacter pylori infection by Lactobacillus acidophilus in C57BL/6 mice

Objective To investigate the potential effects of Lactobacillus acidophilus strain L6 on prevention and treatment of Helicobacter pylori (H. pylori) infection in animal models. Methods A total of 200 hundred C57BL/6 mice were used in the study. ① Sixty mice were divided into control group (infected with H. pylori) and prevention group (previously treated with L6 and followed by infection with H. pylori) with 30 each. The incidence of H. pylori infection was compared between two groups.② Sixty mice were divided into control group (infected with H. pylori) and treatment group (infected with H. pylori for 4 weeks and followed by treatment with L6) with 30 each. The changes of H. pylori infection was compared between tow groups. ③ Eighty mice previously infected with H. pylori were orally administrated with L6 in the water supply over a period of 9 months. Of which, 40 H. pylori negative mice were either continuously or discontinuously treated with L6. The re-infection of H. pylori was compared between two groups. The H. pylori infection, gastric mucosal inflammatory and serum anti-H. pylori-lgG titer was measured by using urea breath test, histopathology and ELISA, respectively. Results The positive rate of H. pylori infection was 100% in control group and 20% in prevention group (pre-treated with L6 for 1 week). Whereas there was no H. pylori infection in the rest mice of prevention group pre-treated with L6 for 2 or 4 weeks. There was significant difference in H. pylori infection between two groups (P<0. 05). The serum anti-H. pylori IgG titer was lower in treatment group than in control group (P<0. 05). The reinfection of H. pylori in mice continuously treated with L6 was significantly lower than those discontiously treated with L6 (P<0. 05). Conclusions Preventively feeding L6 can significantly reduce the H. pylori infection in C57BL/6 mice, whereas the inhibition of H. pylori re-infection can also be achieved with long-term administration of L6. Key words: Lactobacillusacidophilus; Helicobacter pylori; Animal experimentation

Research on correlative factor of spinal segment distribution in cervical hyperextension injury

Objective To discuss the degenerative factors, the spinal segment distribution, and the mechanism in hyperextension injury of cervical spine. Method Eighty-nine patients with hyperextension injury of cervical spine were retrospectively analyzed by observing the degenerativelesion, the spinal cord segment with high signal in T2WI, and the location of facial trauma. Results Fifty-eight cases showed the disc hemiation which was the most common lesion, followed by 8 cases showing the calcification of the posterior longitudinal ligament. Besides, 7 cases presented the developmental stenosis of spinal canal, and also, 6 cases showed disc hemiation combined with the yellow ligament hypertrophy. The intervertebral level of the spinal cord with high signal in T2WI were distributed as follows:4 cases were at C2/3, of which onesuffered the forehead trauma; 12 cases were at C3/ 4, of which 10 had the forehead trauma, and one had the zygomatic trauma; 12 cases were at C4/5, of which 5 had the forehead trauma, one had both the zygomatic and the forehead trauma, and one had both the forehead and with the lower jaw trauma; 11 cases were at CS/6,of which 3 had the forehead trauma, 3 had the zygomatic trauma, and 2 had the lower jaw trauma. The location of the spinal cord with single high signal in T2WI did not correspond with the intervertebral disc level in 4 cases. For 10 cases the high signal in T2WI was found at two discontinuous segments. For 2 cases the 1 high signal in T2WI was found at over two segments. For 6 cases the high signal in T2WI was found at over three segments. Conclusions Disc hemiation is the most common underlyding factor in cervical hyperextension injury. The spinal level with high signal in T2WI was correlative to the impacted facial site. The shear force at the inflection point with or without the anterior-posterior compression force accounted for the cervical hyperextension injury. Key words: Cervical spine; Degeneration; Hyperextension injury; Segment distribution of injury; Vertebral dynamic change

Identification of aerodynamic characteristics with discontinuities of the first kind from trajectory data for a free-flying object

A method is proposed for identifying the aerodynamic characteristics of a model the flow about which varies considerably in the course of motion. In this method, the trajectory of the model is split into sections with different types of the flow and then similar data from these sections are collected into groups and processed. The aerodynamic characteristics are identified by the method of successive approximation using a differential correction algorithm. The accuracy of the results is analyzed.

“The Hard Hunger”: Famine, Sexuality, and Form in Eugene McCabe’s Tales from the Poorhouse

By the end of the nineteenth century Ireland had, in many respects, assumed the aspect of a quintessential Gothic landscape "with all its nationalist and all its Gothic graves, with all its mouldering estates and emerging farms, its Land Acts, and its history of confiscations."1 The contested nature of the Irish geo graphical and cultural landscapes meant that these topographies were haunted by the disinherited revenants of colonial misappropriation. Any Romantic san itization of Ireland's rugged terrain for the purposes of tourism belied the frac tious memorial inheritances of the country's disenfranchised population. Indeed, the Gothic had emerged, at least in part, to serve as a form of exfoliant of past injustice; as Leslie Fiedler observes, the Gothic "had been invented to deal with the past and with history from a typically Protestant and enlightened point of view."2 Fiedler's point resonates with both late nineteenthand late twentieth-century narrations of Irish history. The Gothic in Ireland reveals that the past is not easily confined to the com posed rhetoric and streamlined contours of historical writing. The Irish land scape, punctuated with the fragments of edifices, bespeaks a culture of discon tinuous and unsettled histories. Political writings and speeches before and during the nineteenth century frequently figure Ireland as a haunted country. For example, William O'Brien's speech before the Cork Young Ireland Society in 1885 is saturated in Gothic rhetoric. O'Brien invokes the dead generations, and asserts defiantly that

Digital Waveguide Modeling for Wind Instruments: Building a State–Space Representation Based on the Webster–Lokshin Model

This paper deals with digital waveguide modeling of wind instruments. It presents the application of state-space representations for the refined acoustic model of Webster-Lokshin. This acoustic model describes the propagation of longitudinal waves in axisymmetric acoustic pipes with a varying cross-section, visco-thermal losses at the walls, and without assuming planar or spherical waves. Moreover, three types of discontinuities of the shape can be taken into account (radius, slope, and curvature). The purpose of this work is to build low-cost digital simulations in the time domain based on the Webster-Lokshin model. First, decomposing a resonator into independent elementary parts and isolating delay operators lead to a Kelly-Lochbaum network of input/output systems and delays. Second, for a systematic assembling of elements, their state-space representations are derived in discrete time. Then, standard tools of automatic control are used to reduce the complexity of digital simulations in the time domain. The method is applied to a real trombone, and results of simulations are presented and compared with measurements. This method seems to be a promising approach in term of modularity, complexity of calculation, and accuracy, for any acoustic resonators based on tubes.

On the steady-state structure of shock waves in elastic media and dielectrics

A simplified system of equations describing small-amplitude nonlinear quasi-transverse waves in an elastic weakly anisotropic medium with complicated dissipation and dispersion is considered. A simplified system of equations derived for describing the propagation and evolution of one-dimensional weakly nonlinear electromagnetic waves in a weakly anisotropic dielectric is found to be of the same type as the system of equations for quasi-transverse waves in an elastic medium. The steady-state structure of small-amplitude quasi-transverse discontinuities and a large number of admissible discontinuity types is studied using this system of equations. Viscous dissipation is traditionally assumed to be described in terms of the next differentiation order as compared to those constituting the hyperbolic system describing long waves, while the terms responsible for dispersion have an even higher differentiation order.

Calculated Sound Velocity Change in LaFeAsO0.89F0.11 at the Superconducting Transition

The changes in the bulk modulus and sound velocity in LaFeAsO0.89F0.11 superconductor at the transition temperature were calculated using various thermodynamic data. Step discontinuities of 16 ppm in the bulk modulus and 5 ppm in the longitudinal sound velocity are expected at the superconducting transition. The calculated acoustic Debye temperature for the parent compound is 367 K and this is slightly higher than the values determined by specific heat measurements for LaO0.89F0.11FeAs.

INFLUENCE OF T6I6 TEMPER ON TENSILE AND INTERGRANULAR CORROSION PROPERTIES OF 6061 ALUMINUM ALLOY

It is important to achieve a good combinization of high tensile properties and high intergranular corrosion resistance for 6000 series alloys in wider applications.In this paper,the effect of T6I6 temper on tensile and intergranular corrosion properties of 6061 aluminum alloy was investigated by tensile test,intergranular corrosion test,OM and TEM.The experimental results show that after T6 temper the ultimate strength and yield strength of 6061 alloy are 356.0 and 331.6 MPa respectively, but it has a serious tendency to intergranular corrosion sensitivity.It is found that pre-ageing time of T6I6 temper has no remarked effect on tensile properties of the alloy,but interrupted temperature and interrupted time have obvious effects on its tensile and intergranular corrosion properties.After T6I6 treatment,the tensile strength of 6061 aluminium alloy reaches its peak strength firstly and then decreases to a small value with the increase of interrupted time after pre-ageing at interrupted temperature of 150℃,and the corrosion mode also changes from intergranular to uniform corrosion.Higher interrupted temperature and longer interrupted time are beneficial to achieve a good combinization of tensile properties and intergranular corrosion resistance,which results from the high density of precipitates inside grains and discontinuously distributed precipitates on grain boundaries.After an optimum T6I6 treatment of 180℃×2 h+150℃×2160 h+180℃×8 h,the ultimate strength and yield strength are 348.5 and 326.9 MPa respectively,close to those after T6 temper.The corrosion mode is changed from the intergranular corrosion of 6061 Al alloy after T6 temper to a uniform etching with the etching depth about 30μm.

Clinical assessment of pediatric anthropometry

Children are special groups who grow rapidly,the characteristics of physical growth are discontinuous,and individual in different stages.Growth level,growth velocity and proportion of body need in consideration for a proper assessment and explanation of growth status in children. Key words: Children; Growth and development; Evaluation

Behavior of Nemopsis bachei L. Agassiz, 1849 medusae in the presence of physical gradients and biological thin layers

In pelagic systems, thin layers (discontinuities with narrow vertical extents and high concentrations of organisms) create patches of food, and aggregations of gelatinous zooplankton can exploit such resources. The establishment, maintenance, and trophic effects of these functional relationships depend on behavioral responses to thin layers by individuals, which remain largely unexplored. In this study, we used laboratory experiments to test the hypothesis that a common and abundant hydromedusa predator, Nemopsis bachei L. Agassiz, 1849, would respond similarly to salinity gradients with and without thin layers of algae and copepods. Approximately 75% of the hydromedusae remained in both types of discontinuities. These distributions were not created solely by passive responses related to osmoconformation or an inability to swim through salinity gradients because approximately 25% of hydromedusae swam through or away from salinity gradients or biological thin layers. Biological thin layers stimulated feeding. Feeding success was related directly to encounter rates and it was independent of swimming, as expected for an ambush predator. Feeding increased at higher prey densities, and capture, handling time, and ingestion were not saturated even at 150–200 copepods l−1. The proportion of N. bachei that ceased feeding and began swimming increased when encounters with prey decreased to approximately 2 encounters hydromedusa−1 10 min−1. Thus, hydromedusae may seek new patches of prey once encounter rates and subsequent feeding success fall below a threshold. Exposing N. bachei to salinity gradients with and without biological thin layers indicated that these hydromedusae will remain in discontinuities and exert predation pressure that should be considered when assessing trophic webs and estimating carbon flux.

Spatial organization of multiple plant species in arid ecosystems: linking patterns and processes

Spatial organization of multiple plant species that appears as a non-random distribution of vegetative patches is one of the mostly observed spatial patterns in arid ecosystems. Yet understanding of ecological processes allowing this spatial pattern to emerge through interspecific interactions is still lacking. With a proposed conceptual model involving interspecific trade-offs between species competitive ability and colonization ability, we have argued that within patch abundance dynamics regulated by the mechanisms of competition are strongly influenced by the between patches colonization dynamics that are maintained via this trade-offs and it holds a positive, intraspecific occupancy-abundance relationship, in which increased patch occupancy increases species density within inhabiting patches. In a constant environment, while local abundance dynamics approach toward a stable equilibrium point, a fixed spatial arrangement of spe- cies can be retained through this coupled dynamics. However, in fluctuating environments where existence of such stable equilibriums is highly uncertain, it may involve continuous transitions from one community state to another as species re-organized themselves over space through the rapid changes in local species abundances. While some of the inhabiting patches are destroyed exogenously or endogenously, or species responses to increasing environmental fluctuations vary increasingly with time, discontinuous transitions into an abrupt, irreversible state of the community dynamics may occur, as with this effect the inherent positive relationship between occupancy and abundance of species is no longer maintained.

Characteristics of the wave form of intrabronchial spark sounds on the chest wall and discontinuous adventitious lung sounds (author's transl)

Characteristics of the wave form of intrabronchial spark sounds on the chest wall and discontinuous adventitious lung sounds (author's transl)

Procoagulant activity of alveolar macrophages in bleomycin-induced lung fibrosis in rats

Interstitial and intraalveolar fibrin deposition is a prominent feature in adult respiratory distress syndrome and is also observed in the inflammatory phase of interstitial lung disease (ILD). It is suggested that the coagulation abnormality in these disorders may be implicated in the pathogenesis of subsequent fibrosis of the lung. In this study, we examined the procoagulant activity (PCA) of alveolar macrophages during the development of bleomycin-induced lung fibrosis in rats. The PCA of alveolar macrophages was significantly increased at 2, 7 and 14 days after the intratracheal administration of bleomycin compared with that of control rats. The greatest PCA was observed at 7 days after the bleomycin injection, the inflammatory phase in the development of lung fibrosis. Increased PCA returned to the normal value at 21 days, while the fibrotic process advanced and the collagen content increased in the lung. Alveolar macrophages at 7 days after the administration of bleomycin or saline were separated into five density fractions on discontinuous Percoll gradients. The increase in the percentage of low-density macrophages was observed in bleomycin-injected rats. The greatest PCA was demonstrated in the lowest-density fraction (specific gravity less than 1.030), while reduced activities were observed in the higher-density fractions, in each group. The increased PCA of alveolar macrophages during lung injury was due in part to the increase of low-density subpopulation, which had greater PCA, although the fibrin deposition in the development of lung fibrosis remained to be defined, the increase of coagulation pathways may contribute to the progression of interstitial fibrotic lung diseases.