Journal articles: 'Critical sequence of points'

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SCHECHTER, MARTIN. "Linking sandwich pairs." Mathematical Proceedings of the Cambridge Philosophical Society 147, no. 3 (June 15, 2009): 679–700. http://dx.doi.org/10.1017/s0305004109990089.

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AbstractSince the development of the calculus of variations there has been interest in finding critical points of functionals. This was intensified by the fact that for many equations arising in practice, the solutions are critical points. In searching for critical points, there is a distinct advantage if the functional G is semibounded. In this case one can find a Palais–Smale (PS) sequence or even a Cerami sequence These sequences produce critical points if they have convergent subsequences. However, there is no clear method of finding critical points of functionals which are not semibounded. Linking subsets do provide such a method. They can produce a PS sequence provided they separate the functional. In the present paper we show that there are pairs of subsets that can produce Cerami-like sequences even though they do not separate the functional. All that is required is that the functional be bounded from above on one of the sets and bounded from below on the other, with no relationship needed between the bounds. This provides a distinct advantage in applications. We apply the method to several situations.

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Schechter, Martin. "The Use of Cerami Sequences in Critical Point Theory." Abstract and Applied Analysis 2007 (2007): 1–28. http://dx.doi.org/10.1155/2007/58948.

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The concept of linking was developed to produce Palais-Smale (PS) sequencesG(uk)→a,G'(uk)→0forC1functionalsGthat separate linking sets. These sequences produce critical points if they have convergent subsequences (i.e., ifGsatisfies the PS condition). In the past, we have shown that PS sequences can be obtained even when linking does not exist. We now show that such situations produce more useful sequences. They not only produce PS sequences, but also Cerami sequences satisfyingG(uk)→a,(1+||uk||)G'(uk)→ 0as well. A Cerami sequence can produce a critical point even when a PS sequence does not. In this situation, it is no longer necessary to show thatGsatisfies the PS condition, but only that it satisfies the easier Cerami condition (i.e., that Cerami sequences have convergent subsequences). We provide examples and applications. We also give generalizations to situations when the separating criterion is violated.

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Zhang, Peng, and Chun-Lei Tang. "Infinitely Many Periodic Solutions for Nonautonomous Sublinear Second-Order Hamiltonian Systems." Abstract and Applied Analysis 2010 (2010): 1–10. http://dx.doi.org/10.1155/2010/620438.

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Two sequences of distinct periodic solutions for second-order Hamiltonian systems with sublinear nonlinearity are obtained by using the minimax methods. One sequence of solutions is local minimum points of functional, and the other is minimax type critical points of functional. We do not assume any symmetry condition on nonlinearity.

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LI, YUXIANG, and YOUDE WANG. "BUBBLING LOCATION FOR SEQUENCES OF APPROXIMATE f-HARMONIC MAPS FROM SURFACES." International Journal of Mathematics 21, no. 04 (April 2010): 475–95. http://dx.doi.org/10.1142/s0129167x10006136.

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Let f be a positive smooth function on a closed Riemann surface (M, g). The f-energy of a map u from M to a Riemannian manifold (N, h) is defined as [Formula: see text] and its L2-gradient is: [Formula: see text] We will study the blow-up properties of some approximate f-harmonic map sequences in this paper. For a sequence uk : M → N with ‖τf(uk)‖L2 < C1 and Ef(uk) < C2, we will show that, if the sequence is not compact, then it must blow-up at some critical points of f or some concentrate points of |τf(uk)|2dVg. For a minimizing α-f-harmonic map sequence in some homotopy class of maps from M into N we show that, if the sequence is not compact, the blow-up points must be the minimal point of f and the energy identity holds true.

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Harju, Tero. "Critical factorisation in square-free words." RAIRO - Theoretical Informatics and Applications 56 (2022): 3. http://dx.doi.org/10.1051/ita/2022003.

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A position p in a word w is critical if the minimal local period at p is equal to the global period of w. According to the Critical Factorisation Theorem all words of length at least two have a critical point. We study the number η(w) of critical points of square-free ternary words w, i.e., words over a three letter alphabet. We show that the sufficiently long square-free words w satisfy η(w) ≤|w|− 5 where |w| denotes the length of w. Moreover, the bound |w|− 5 is reached by infinitely many words. On the other hand, every square-free word w has at least |w|∕4 critical points, and there is a sequence of these words closing to this bound.

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Amir, Fouzia, Ali Farajzadeh, and Narin Petrot. "Proximal point algorithm for differentiable quasi-convex multiobjective optimization." Filomat 34, no. 7 (2020): 2367–76. http://dx.doi.org/10.2298/fil2007367a.

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The main aim of this paper is to consider the proximal point method for solving multiobjective optimization problem under the differentiability, locally Lipschitz and quasi-convex conditions of the objective function. The control conditions to guarantee that the accumulation points of any generated sequence, are Pareto critical points are provided.

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Wang, Tao, Jiang-hua Huang, Lin Lin, and Chang'an A. Zhan. "Continuous- and Discrete-Time Stimulus Sequences for High Stimulus Rate Paradigm in Evoked Potential Studies." Computational and Mathematical Methods in Medicine 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/396034.

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To obtain reliable transient auditory evoked potentials (AEPs) from EEGs recorded using high stimulus rate (HSR) paradigm, it is critical to design the stimulus sequences of appropriate frequency properties. Traditionally, the individual stimulus events in a stimulus sequence occur only at discrete time points dependent on the sampling frequency of the recording system and the duration of stimulus sequence. This dependency likely causes the implementation of suboptimal stimulus sequences, sacrificing the reliability of resulting AEPs. In this paper, we explicate the use of continuous-time stimulus sequence for HSR paradigm, which is independent of the discrete electroencephalogram (EEG) recording system. We employ simulation studies to examine the applicability of the continuous-time stimulus sequences and the impacts of sampling frequency on AEPs in traditional studies using discrete-time design. Results from these studies show that the continuous-time sequences can offer better frequency properties and improve the reliability of recovered AEPs. Furthermore, we find that the errors in the recovered AEPs depend critically on the sampling frequencies of experimental systems, and their relationship can be fitted using a reciprocal function. As such, our study contributes to the literature by demonstrating the applicability and advantages of continuous-time stimulus sequences for HSR paradigm and by revealing the relationship between the reliability of AEPs and sampling frequencies of the experimental systems when discrete-time stimulus sequences are used in traditional manner for the HSR paradigm.

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Christodoulou, Dimitris M., Demosthenes Kazanas, Isaac Shlosman, and Joel E. Tohline. "Phase-Transition Theory of Instabilities. IV. Critical Points on the Maclaurin Sequence and Nonlinear Fission Processes." Astrophysical Journal 446 (June 1995): 510. http://dx.doi.org/10.1086/175809.

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RAMADAS, ROHINI. "Dynamical degrees of Hurwitz correspondences." Ergodic Theory and Dynamical Systems 40, no. 7 (December 4, 2018): 1968–90. http://dx.doi.org/10.1017/etds.2018.125.

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Let $\unicode[STIX]{x1D719}$ be a post-critically finite branched covering of a two-sphere. By work of Koch, the Thurston pullback map induced by $\unicode[STIX]{x1D719}$ on Teichmüller space descends to a multivalued self-map—a Hurwitz correspondence ${\mathcal{H}}_{\unicode[STIX]{x1D719}}$—of the moduli space ${\mathcal{M}}_{0,\mathbf{P}}$. We study the dynamics of Hurwitz correspondences via numerical invariants called dynamical degrees. We show that the sequence of dynamical degrees of ${\mathcal{H}}_{\unicode[STIX]{x1D719}}$ is always non-increasing and that the behavior of this sequence is constrained by the behavior of $\unicode[STIX]{x1D719}$ at and near points of its post-critical set.

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Albers, Gerhard, Leonidas J. Guibas, Joseph S. B. Mitchell, and Thomas Roos. "Voronoi Diagrams of Moving Points." International Journal of Computational Geometry & Applications 08, no. 03 (June 1998): 365–79. http://dx.doi.org/10.1142/s0218195998000187.

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Consider a set of n points in d-dimensional Euclidean space, d ≥ 2, each of which is continuously moving along a given individual trajectory. As the points move, their Voronoi diagram changes continuously, but at certain critical instants in time, topological events occur that cause a change in the Voronoi diagram. In this paper, we present a method of maintaining the Voronoi diagram over time, at a cost of O( log n) per event, while showing that the number of topological events has an upper bound of O(ndλs(n)), where λs(n) is the (nearly linear) maximum length of a (n,s)-Davenport-Schinzel sequence, and s is a constant depending on the motions of the point sites. In addition, we show that if only k points are moving (while leaving the other n - k points fixed), there is an upper bound of O(knd-1λs(n)+(n-k)dλ s(k)) on the number of topological events.

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Whicker, Marcia Lynn, and Malcolm E. Jewell. "Rejoinder to Hadley." American Review of Politics 14 (April 1, 1993): 123–27. http://dx.doi.org/10.15763/issn.2374-7781.1993.14.0.123-127.

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Charles D. Hadley has made several interesting points, including some legitimate criticisms of our study. Some criticisms, however, are less relevant and do not undermine the integrity of our effort. We shall discuss his points in sequence: Confusion over “critical” and “realigning” elections. Hadley contends that we have confused critical and realigning elections. We acknowledge that perhaps we have been too loose with our use of terminology. His point that critical elections, representing a fundamental shift in the political attitudes and preferences of the populace, may be divided into realigning and converting subsets is well taken. We have erred in using the terms “critical election” and “realigning election” interchangeably, and should have restricted ourselves to using the former. This misuse of terms, however, is incidental to our analysis, since we have analyzed all critical elections from the founding of the country to the present, with special attention to the four critical elections about which there is the greatest agreement (1828, 1860, 1896, and 1932).

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Molloy, Michael, and Bruce Reed. "A critical point for random graphs with a given degree sequence." Random Structures & Algorithms 6, no. 2-3 (March 1995): 161–80. http://dx.doi.org/10.1002/rsa.3240060204.

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KALOSHIN, V., and O. S. KOZLOVSKI. "A Cr unimodal map with an arbitrary fast growth of the number of periodic points." Ergodic Theory and Dynamical Systems 32, no. 1 (April 19, 2011): 159–65. http://dx.doi.org/10.1017/s0143385710000817.

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AbstractIn this paper we present a surprising example of a Cr unimodal map of an interval f:I→I whose number of periodic points Pn(f)=∣{x∈I:fnx=x}∣ grows faster than any ahead given sequence along a subsequence nk=3k. This example also shows that ‘non-flatness’ of critical points is necessary for the Martens–de Melo–van Strien theorem [M. Martens, W. de Melo and S. van Strien. Julia–Fatou–Sullivan theory for real one-dimensional dynamics. Acta Math.168(3–4) (1992), 273–318] to hold.

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DILÃO, RUI, and JOSÉ AMIGÓ. "COMPUTING THE TOPOLOGICAL ENTROPY OF UNIMODAL MAPS." International Journal of Bifurcation and Chaos 22, no. 06 (June 2012): 1250152. http://dx.doi.org/10.1142/s0218127412501520.

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We derive an algorithm to determine recursively the lap number (minimal number of monotone pieces) of the iterates of unimodal maps of an interval with free end-points. For this family of maps, the kneading sequence does not determine the lap numbers. The algorithm is obtained by the sign analysis of the itineraries of the critical point and of the boundary points of the interval map. We apply this algorithm to the estimation of the growth number and the topological entropy of maps with direct and reverse bifurcations.

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BERTOLIM, M. A., D. V. S. LIMA, M. P. MELLO, K. A. DE REZENDE, and M. R. DA SILVEIRA. "A global two-dimensional version of Smale’s cancellation theorem via spectral sequences." Ergodic Theory and Dynamical Systems 36, no. 6 (March 19, 2015): 1795–838. http://dx.doi.org/10.1017/etds.2014.142.

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In this article, Conley’s connection matrix theory and a spectral sequence analysis of a filtered Morse chain complex $(C,{\rm\Delta})$ are used to study global continuation results for flows on surfaces. The briefly described unfoldings of Lyapunov graphs have been proved to be a well-suited combinatorial tool to keep track of continuations. The novelty herein is a global dynamical cancellation theorem inferred from the differentials of the spectral sequence $(E^{r},d^{r})$. The local version of this theorem relates differentials $d^{r}$ of the $r$th page $E^{r}$ to Smale’s theorem on cancellation of critical points.

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CANDITO, PASQUALE, ROBERTO LIVREA, and DUMITRU MOTREANU. "2-SYMMETRIC CRITICAL POINT THEOREMS FOR NON-DIFFERENTIABLE FUNCTIONS." Glasgow Mathematical Journal 50, no. 3 (September 2008): 447–66. http://dx.doi.org/10.1017/s0017089508004333.

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AbstractIn this paper, some min–max theorems for even andC1functionals established by Ghoussoub are extended to the case of functionals that are the sum of a locally Lipschitz continuous, even term and a convex, proper, lower semi-continuous, even function. A class of non-smooth functionals admitting an unbounded sequence of critical values is also pointed out.

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MICHEL, M. E., J. T. KEETON, and G. R. ACUFF. "Pathogen Survival in Precooked Beef Products and Determination of Critical Control Points in Processing." Journal of Food Protection 54, no. 10 (October 1, 1991): 767–72. http://dx.doi.org/10.4315/0362-028x-54.10.767.

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Surfaces of precooked, roast beef slices were inoculated with Clostridium perfringens, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, or Listeria monocytogenes, vacuum packaged and then stored at 3°C for 70 d to determine survival of pathogens under extended refrigerated storage in the presence of a natural competing microflora. S. typhimurium and L. monocytogenes remained present on the slices for the duration of the experiment. Numbers of S. aureus did not decrease significantly (P>0.05), and counts of C. perfringens decreased steadily over the 70-d storage period. Numbers of E. coli also declined, but more rapidly than the other pathogens during initial storage of the product. Total bacterial numbers for both uninoculated (control) and inoculated slices were similar. Samples obtained at selected locations in the processing sequence of a commercial restructured beef product contained L. monocytogenes at most sampling locations prior to heat processing, but not after heating. Salmonella was occasionally isolated from the product prior to heating. Total bacterial numbers decreased as processing day progressed, as did counts for S. aureus, E. coli, and coliforms. Counts of S. aureus and total bacterial numbers increased after the cooked product was removed from the package and coated with a seasoning mix. Data collected in this study support the designation of the following locations as critical control points: initial bacterial levels on raw products, cooking temperature and time, proper cooling after cooking, sanitation after opening the package (rubbing with seasonings and rebagging), and temperature control of the final product.

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Kruger, F., and S. Scheidl. "Spin and charge ordering transitions in stripes." Journal de Physique IV 12, no. 9 (November 2002): 259–60. http://dx.doi.org/10.1051/jp4:20020409.

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We study the interplay of topological excitations in stripe phases: charge dislocations, charge loops, and spin vortices. In two dimensions these defects interact logarithmically on large distances. Using a renormalization-group analysis in the Coulomb gas representation of these defects, we calculate the phase diagram and the critical properties of the transitions. Depending on the interaction parameters, spin and charge order can disappear at a single transition or in a sequence of two transitions (spin-charge separation). These transitions are non-universal with continuously varying critical exponents. We also determine the nature of the points where three phases coexist.

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LECHTENFELD, OLAF. "EIGENVALUE TUNNELING IN MATRIX MODELS." International Journal of Modern Physics A 07, no. 10 (April 20, 1992): 2335–54. http://dx.doi.org/10.1142/s0217751x92001046.

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We investigate the nonperturbative physics of the zero-dimensional random Hermitian matrix model, using semiclassical analysis as well as orthogonal polynomials. Finite-N tunneling leads to a unique equilibration of the Dyson gas of eigenvalues and dissolves a fictitious family of N=∞ saddle points. We present a mean-field potential for the limiting multiple-arc eigenvalue distribution. The sequence of the orthogonal-polynomial recursion coefficients Rk is characterized by the critical points of the matrix potential. Its large-N limit can show regions of smooth, quasi-periodic and seemingly chaotic behavior. The tunneling competition between nondegenerate potential wells is the origin of the unpredictability.

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Steuding, Jörn, and Ade Irma Suriajaya. "Value-Distribution of the Riemann Zeta-Function Along Its Julia Lines." Computational Methods and Function Theory 20, no. 3-4 (April 3, 2020): 389–401. http://dx.doi.org/10.1007/s40315-020-00316-x.

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AbstractFor an arbitrary complex number $$a\ne 0$$ a ≠ 0 we consider the distribution of values of the Riemann zeta-function $$\zeta $$ ζ at the a-points of the function $$\Delta $$ Δ which appears in the functional equation $$\zeta (s)=\Delta (s)\zeta (1-s)$$ ζ ( s ) = Δ ( s ) ζ ( 1 - s ) . These a-points $$\delta _a$$ δ a are clustered around the critical line $$1/2+i\mathbb {R}$$ 1 / 2 + i R which happens to be a Julia line for the essential singularity of $$\zeta $$ ζ at infinity. We observe a remarkable average behaviour for the sequence of values $$\zeta (\delta _a)$$ ζ ( δ a ) .

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Liebold, F., and H. G. Maas. "Strategy for Crack Width Measurement of Multiple Crack Patterns in Civil Engineering Material Testing Using a Monocular Image Sequence Analysis." PFG – Journal of Photogrammetry, Remote Sensing and Geoinformation Science 88, no. 3-4 (February 26, 2020): 219–38. http://dx.doi.org/10.1007/s41064-020-00103-2.

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Abstract An image sequence analysis procedure is developed to quantitatively analyze complex multiple crack patterns in tension tests of fiber-reinforced composite specimens. Planar textured surfaces of such specimens can be observed with a monocular image sequence using a camera of suitable spatial and temporal resolution. Due to the narrow crack paths, a dense high-precision displacement vector field is computed applying least-squares image matching techniques. Some uniformly distributed matching points are triangulated into a mesh. To measure deformations, principal strains and crack widths are computed for each face. Stretched triangles presumably containing one or multiple cracks are subdivided into three new triangles to densify the mesh in critical regions. The subdivision is repeated for some iterations. The crack width computation of the triangles requires at least three vertices and its displacements. Due to the dense displacement vector field, there are more points available. In this paper, an algorithm for the crack width computation in a least-squares fit is presented.

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Geum, Young Hee, and Young Ik Kim. "On Locating and Counting Satellite Components Born along the Stability Circle in the Parameter Space for a Family of Jarratt-Like Iterative Methods." Mathematics 7, no. 9 (September 11, 2019): 839. http://dx.doi.org/10.3390/math7090839.

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This paper is devoted to an analysis on locating and counting satellite components born along the stability circle in the parameter space for a family of Jarratt-like iterative methods. An elementary theory of plane geometric curves is pursued to locate bifurcation points of such satellite components. In addition, the theory of Farey sequence is adopted to count the number of the satellite components as well as to characterize relationships between the bifurcation points. A linear stability theory on local bifurcations is developed based upon a small perturbation about the fixed point of the iterative map with a control parameter. Some properties of fixed and critical points under the Möbius conjugacy map are investigated. Theories and examples on locating and counting bifurcation points of satellite components in the parameter space are presented to analyze the bifurcation behavior underlying the dynamics behind the iterative map.

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Chang, Zuling, Pinhui Ke, and Yongcheng Zhao. "Some Enumeration Results on Binary 2n-Periodic Sequences." International Journal of Foundations of Computer Science 28, no. 02 (February 2017): 171–84. http://dx.doi.org/10.1142/s0129054117500113.

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This paper studies some enumeration problems of binary sequences with period 2n based on the Games-Chan algorithm and a modified Stamp-Martin algorithm. We provide the exact number of critical error sequences of binary 2n-periodic sequences corresponding to the second critical point. The exact formula for the number of binary 2n-periodic sequences with exactly three critical points is also derived.

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LAMPREIA, J. P., and J. SOUSA RAMOS. "TRIMODAL MAPS." International Journal of Bifurcation and Chaos 03, no. 06 (December 1993): 1607–17. http://dx.doi.org/10.1142/s0218127493001276.

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In this paper we present a result that establishes the admissibility rules for the symbolic sequences that are realizable as orbits of the critical points of three parameter families of maps on the interval with three critical points. We also introduce a method that simplifies the calculation of the topological entropy for these maps.

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SECCHI, SIMONE, and MARCO SQUASSINA. "ON THE LOCATION OF SPIKES FOR THE SCHRÖDINGER EQUATION WITH ELECTROMAGNETIC FIELD." Communications in Contemporary Mathematics 07, no. 02 (April 2005): 251–68. http://dx.doi.org/10.1142/s0219199705001738.

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We consider the standing wave solutions of the three dimensional semilinear Schrödinger equation with competing potential functions V and K and under the action of an external electromagnetic field B. We establish some necessary conditions for a sequence of such solutions to concentrate, in two different senses, around a given point. In the particular but important case of nonlinearities of power type, the spikes locate at the critical points of a smooth ground energy map independent of B.

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Dubinin, E. M., K. Sauer, and J. F. McKenzie. "Nonlinear 1-D stationary flows in multi-ion plasmas – sonic and critical loci – solitary and "oscillatory" waves." Annales Geophysicae 24, no. 11 (November 22, 2006): 3041–57. http://dx.doi.org/10.5194/angeo-24-3041-2006.

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Abstract. One-dimensional stationary flows of a plasma consisting of two ion populations and electrons streaming against a heavy ion cloud are studied. The flow structure is critically governed by the position of sonic and critical points, at which the flow is shocked or choked. The concept of sonic and critical points is suitably generalized to the case of multi-ion plasmas to include a differential ion streaming. For magnetic field free flows, the sonic and critical loci in the (upx, uhx) space coincide. Amongst the different flow patterns for the protons and heavy ions, there is a possible configuration composed of a "heavy ion shock" accompanied by a proton rarefaction. The magnetic field introduces a "stiffness" for the differential ion streaming transverse to the magnetic field. In general, both ion fluids respond similarly in the presence of "ion obstacle"; the superfast (subfast) flows are decelerated (accelerated). The collective flow is choked when the dynamic trajectory (upx, uhx) crosses the critical loci. In specific regimes the flow contains a sequence of solitary structures and as a result, the flow is strongly bunched. In each such substructure the protons are almost completely replaced by the heavies. A differential ion streaming is more accessible in the collective flows oblique to the magnetic field. Such a flexibility of the ion motion is determined by the properties of energy integrals and the Bernoulli energy functions of each ion species. The structure of flows, oblique to the magnetic field, depends critically on the velocity regime and demonstrates a rich variety of solitary and oscillatory nonlinear wave structures. The results of the paper are relevant to the plasma and field environments at comets and planets through the interaction with the solar wind.

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Eccleston, Marcus, Andrew Willems, Adam Beveridge, and Justin R. Nodwell. "Critical Residues and Novel Effects of Overexpression of the Streptomyces coelicolor Developmental Protein BldB: Evidence for a Critical Interacting Partner." Journal of Bacteriology 188, no. 23 (September 8, 2006): 8189–95. http://dx.doi.org/10.1128/jb.01119-06.

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ABSTRACT The bldB gene of Streptomyces coelicolor encodes the best-characterized member of a family of small proteins that have low isoelectric points but that lack any previously characterized sequence motifs. BldB is dimeric and is required for the efficient production of antibiotics and spore-forming cells, called aerial hyphae, by growing colonies. The mechanism of action of BldB and its relatives is unknown. Here, we have explored amino acids in BldB that either are highly conserved or have been implicated in function genetically. We show that five amino acids are important for its function at physiological expression levels. Mutations in three of these amino acids gave rise to proteins that were either monomeric or unstable in vivo, while two others are not. We find that overexpression of bldB in S. coelicolor blocks sporulation prior to sporulation-specific septation but permits the formation of aerial hyphae. Vegetative septation was apparently normal in both the bldB null mutant and the bldB overexpression strain. To our surprise, overexpression of the dimerization-competent but functionally defective alleles caused a dramatic acceleration of sporulation. Our results suggest that BldB makes at least one important contact with another subcellular constituent and that a loss or alteration of this interaction impairs the phenotypic properties of the organism.

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Tian, Yu, and Juan J. Nieto. "The Applications of Critical-Point Theory to Discontinuous Fractional-Order Differential Equations." Proceedings of the Edinburgh Mathematical Society 60, no. 4 (March 16, 2017): 1021–51. http://dx.doi.org/10.1017/s001309151600050x.

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AbstractWe consider a fractional equation involving the left and right Riemann–Liouville fractional integrals and with Sturm–Liouville boundary-value conditions. We establish the variational structure of the problem and, by using critical-point theory, the existence of an unbounded sequence of solutions is obtained.

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Moreno, Glaucia Sousa. "AGROTÓXICOS: CONTROVÉRSIAS SOCIOCIENTÍFICAS COMO POSSIBILIDADE DIDÁTICA NO ENSINO DE CIÊNCIAS." Cadernos de Educação Tecnologia e Sociedade 12, no. 4 (December 29, 2019): 373. http://dx.doi.org/10.14571/brajets.v12.n4.373-381.

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This work reports on the socioscientific controversy surrounding the subject of pesticides as a didactic possibility in teaching sciences in basic education. The analysis points out the need to understand the subject by means of scientific, social, economic, environmental and political aspects in a decision-making process. To reach our goal, we have opted for the methodology of “Three Pedagogical Moments”, to structure a didactic sequence thought for the teaching of science in basic education. Thus, it provides an emergency of critical awareness about the consequences of pesticide use and the education of students on the reality of their effects, through contents and / or knowledge of science practiced in schools. This methodology could assist in the development of critical, conscious and consistent teaching that advances in the condition of maximum consciousness for the maximum possible condition of consciousness, based on ethical values, social justice, and environmental responsibility. This work also proposes a structured didactic sequence with interdisciplinary knowledge of sciences of nature in dialogue with the Agrarian sciences.

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Henderson, Nélio, Anderson Alvarenga De Moura Menezes, Wagner F. Sacco, and Nelza E. Barufatti. "Computation of Critical Points of Mixtures Using Particle Swarm Optimization with Low-Discrepancy Sequences." Chemical Engineering Communications 202, no. 11 (September 10, 2014): 1478–92. http://dx.doi.org/10.1080/00986445.2014.947365.

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Kaur, Navjot, and Bhushan J. Toley. "Paper-based nucleic acid amplification tests for point-of-care diagnostics." Analyst 143, no. 10 (2018): 2213–34. http://dx.doi.org/10.1039/c7an01943b.

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IMHOF, LORENS A. "Proof of Lorch's conjecture on ultraspherical polynomials." Mathematical Proceedings of the Cambridge Philosophical Society 132, no. 3 (May 2002): 545–53. http://dx.doi.org/10.1017/s0305004101005746.

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We use a Volterra integral equation to derive lower bounds for the local maxima of |un(θ)| = (sin θ)λ|P(λ)n(cos θ)|, where P(λ)n (·) is the nth ultraspherical polynomial with parameter 0 < λ < 1. Moreover, inequalities for the critical points and inequalities between the extrema of un(θ) and un−1(θ) are obtained. The results are applied to show that, for every λ, the maxima of (n+λ)1−λ|un(θ)| form a strictly increasing sequence. This establishes a conjecture of Lorch [12, 13].

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Stark, Alan E. "Variation in Prevalence of Rare Heritable Traits — A Simulation Study — Illustrated by Neurofibromatosis Type 1." Twin Research and Human Genetics 22, no. 4 (July 25, 2019): 229–32. http://dx.doi.org/10.1017/thg.2019.47.

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AbstractThe epidemiology of heritable traits whose prevalence is determined by a balance between mutation and selection is often explored through deterministic models. Here, the properties are explored by simulation of a model population followed through a sequence of closely spaced time points. Mutation and birth and death occur randomly. The condition neurofibromatosis type 1 (NF1) is used as a point of reference. Critical parameters, such as mutation rates and selection forces, are not known precisely for NF1 so speculative values based on published data from Finland and other studies are proposed.

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Rock, E. P., P. R. Sibbald, M. M. Davis, and Y. H. Chien. "CDR3 length in antigen-specific immune receptors." Journal of Experimental Medicine 179, no. 1 (January 1, 1994): 323–28. http://dx.doi.org/10.1084/jem.179.1.323.

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In both immunoglobulins (Ig) and T cell receptors (TCR), the rearrangement of V, D, and J region sequence elements during lymphocyte maturation creates an enormous degree of diversity in an area referred to as the complementarity determining region 3 (CDR3) loop. Variations in the particular V, D, and J elements used, precise points of recombination, and random nucleotide addition all lead to extensive length and sequence heterogeneity. CDR3 loops are often critical for antigen binding in Igs and appear to provide the principal peptide binding residues in TCRs. To better understand the physical and selective constraints on these sequences, we have compiled information on CDR3 size variation for Ig H, L (kappa and lambda) and TCR alpha, beta, gamma, and delta. Ig H and TCR delta CDR3s are the most variable in size and are significantly longer than L and gamma chains, respectively. In contrast, TCR alpha and beta chain distributions are highly constrained, with nearly identical average CDR3 lengths, and their length distributions are not altered by thymic selection. Perhaps most significantly, these CDR3 length profiles suggest that gamma/delta TCRs are more similar to Igs than to alpha/beta TCRs in their putative ligand binding region, and thus gamma/delta and alpha/beta T cells may have fundamentally different recognition properties.

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Zhang, Yixiong, Mingliang Tao, Kewei Yang, and Zhenmiao Deng. "Video Superresolution Reconstruction Using Iterative Back Projection with Critical-Point Filters Based Image Matching." Advances in Multimedia 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/285969.

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To improve the spatial resolution of reconstructed images/videos, this paper proposes a Superresolution (SR) reconstruction algorithm based on iterative back projection. In the proposed algorithm, image matching using critical-point filters (CPF) is employed to improve the accuracy of image registration. First, a sliding window is used to segment the video sequence. CPF based image matching is then performed between frames in the window to obtain pixel-level motion fields. Finally, high-resolution (HR) frames are reconstructed based on the motion fields using iterative back projection (IBP) algorithm. The CPF based registration algorithm can adapt to various types of motions in real video scenes. Experimental results demonstrate that, compared to optical flow based image matching with IBP algorithm, subjective quality improvement and an average PSNR score of 0.53 dB improvement are obtained by the proposed algorithm, when applied to video sequence.

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Truchado, Pilar, María I. Gil, Ania Pino Querido-Ferreira, Cecilia López Capón, Avelino Álvarez-Ordoñez, and Ana Allende. "Frozen Vegetable Processing Plants Can Harbour Diverse Listeria monocytogenes Populations: Identification of Critical Operations by WGS." Foods 11, no. 11 (May 25, 2022): 1546. http://dx.doi.org/10.3390/foods11111546.

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Frozen vegetables have emerged as a concern due to their association with foodborne outbreaks such as the multi-country outbreak of Listeria monocytogenes serogroup IVb linked to frozen corn. The capacity of L. monocytogenes to colonize food-processing environments is well-known, making the bacteria a real problem for consumers. However, the significance of the processing environment in the contamination of frozen foods is not well established. This study aimed to identify potential contamination niches of L. monocytogenes in a frozen processing plant and characterize the recovered isolates. A frozen vegetable processing plant was monitored before cleaning activities. A total of 78 points were sampled, including frozen vegetables. Environmental samples belonged to food-contact surfaces (FCS); and non-food-contact surfaces (n-FCS). Positive L. monocytogenes samples were found in FCS (n = 4), n-FCS (n = 9), and the final product (n = 1). A whole-genome sequencing (WGS) analysis revealed two clusters belonging to serotypes 1/2a-3a and 1/2b-3b). The genetic characterization revealed the presence of four different sequence types previously detected in the food industry. The isolate obtained from the final product was the same as one isolate found in n-FCS. A multi-virulence-locus sequence typing (MVLST) analysis showed four different virulence types (VT). The results obtained highlight the relevant role that n-FCS such as floors and drains can play in spreading L. monocytogenes contamination to the final product.

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Jeanes, Annette, Fiona Henderson, Nick Drey, and Dinah Gould. "Hand hygiene expectations in radiography: A critical evaluation of the opportunities for and barriers to compliance." Journal of Infection Prevention 20, no. 3 (March 27, 2019): 122–31. http://dx.doi.org/10.1177/1757177419836161.

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Introduction: Good hand hygiene practices reduce the risk of transmission of infection in healthcare. In common with other areas of healthcare, infection control knowledge and practice in radiography has potential for improvement. Regular hand hygiene compliance (HHC) monitoring indicated poor compliance in radiology which did not accurately reflect practice in one organisation. Using a quality improvement cycle, the process and context of work undertaken in radiology were examined in order to improve the validity and utility of HHC monitoring data collection process in the department. Methods: Following examination of the evidence base and with agreement from the radiology team, the chest X-ray process was observed and actions notated. This was then scored using the organisation and the World Health Organization five moments of hand hygiene tool. An alternative risk-based scoring system was developed. Results: The HHC score of 22% was obtained using standard measurements. Achievement of 100% compliance would require the radiographer to clean their hands nine times for each X-ray. The sequence of taking a chest X-ray was examined and two points in the process were identified as key points at which hand cleaning should take place to reduce the risk of transmission of infection. Conclusions: Cleaning hands frequently to achieve compliance expectations in this short low-risk process is neither feasible nor beneficial. A pragmatic risk-based approach to hand hygiene expectations in predictable procedures such as taking a chest X-ray reduces ambiguity and potentially increases compliance.

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Bischi, Gian-Italo, and Laura Gardini. "Basin Fractalization Due to Focal Points in a Class of Triangular Maps." International Journal of Bifurcation and Chaos 07, no. 07 (July 1997): 1555–77. http://dx.doi.org/10.1142/s0218127497001229.

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For a class of rational triangular maps of a plane, characterized by the presence of points in which a component assumes the form [Formula: see text], a new type of bifurcation is evidenced which creates loops in the boundaries of the basins of attraction. In order to explain such bifurcation mechanism, new concepts of focal point and line of focal values are defined, and their effects on the geometric behavior of the map and of its inverses are studied in detail. We prove that the creation of loops, which generally constitute the boundaries of lobes of the basins issuing from the focal points, is determined by contacts between basin boundaries and the line of focal values. A particular map is proposed for which the sequence of such contact bifurcations occurs, causing a fractalization of basin boundaries. Through the analytical and the numerical study of this example new structures of the basins of attraction are evidenced, characterized by fans of stable sets issuing from the focal points, assuming the shape of lobes and arcs, the latter created by the merging of lobes due to contacts between the basin boundaries and the critical curve LC.

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Cholewa, Michał, and Przemysław Głomb. "Estimation of the number of states for gesture recognition with Hidden Markov Models based on the number of critical points in time sequence." Pattern Recognition Letters 34, no. 5 (April 2013): 574–79. http://dx.doi.org/10.1016/j.patrec.2012.12.002.

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Kamm, Judith B., and Aaron J. Nurick. "The Stages of Team Venture Formation: A Decision-making Model." Entrepreneurship Theory and Practice 17, no. 2 (January 1993): 17–27. http://dx.doi.org/10.1177/104225879301700202.

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This model of multi-founder organizational formation assumes that organizations emerge In stages, following an a priori sequence of transitions. The idea stage comes first. In it, individuals or groups within the context of their social networks make decisions about the business concept and what Is needed to implement it. The second stage consists of implementation decisions, Including who will supply resources, what Inducements will be used to attract more partners if necessary, and how the team will be kept together. Feedback loops Indicate that the process may return to the concept and implementation needs decisions, depending upon choices made at certain critical points.

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Yang, In Young, Young Jea Cho, Young Nam Kim, Uk Heo, Sang Guk Park, Kwang Hee Im, Ji Hoon Kim, and Jae Ki Sim. "The Penetration Characteristics of CF/Epoxy Curved Sheller According to Stacking Sequence." Key Engineering Materials 321-323 (October 2006): 885–88. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.885.

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Carbon fiber reinforced plastics, among the advanced composite material watched with keen interests today, is widely used as structural components requiring light weight property because of its high specific strength as well as high specific rigidity. However, this material has a drawback of weakness against a transverse impact loading acting toward the direction of its stacked thickness, which requires different design parameters other than those used for general metal products in actual application. In connection with this point of view, this study utilized specimen of laminated composite material shell having certain radius of curvature considering actual structural component made of laminated CFRP composite material. Penetration experiment was conducted by measuring time of penetration of steel ball between two points where ballistic-screen sensors were attached on front and reverse side of the specimen with the air gun under air pressure that is adjusted by the pressure gauge attached to. Critical penetration energy was found by measuring kinetic energies of the steel ball before and after the penetration. In order to identify crack pattern and penetration mode generated inside the specimen after the experimental penetration, this study used digitalized optical microscope. Through this study, therefore, penetration characteristics by changes in number of layers, by different stacking sequences as well as penetration mode have been observed.

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Volyar, A. V., E. G. Abramochkin, E. V. Razueva, Ya E. Akimova, and M. V. Bretsko. "Structural stability of spiral beams and fine structure of an energy flow." Computer Optics 45, no. 4 (July 2021): 482–89. http://dx.doi.org/10.18287/2412-6179-co-885.

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The problem of structural stability of wave systems with great numbers of degrees of freedom directly concerns the issue of redistribution of energy fluxes in structured vortex beams that ensure their stability under propagating and focusing. A special place in this variety is occupied by spiral vortex beams capable of mapping complex figures, letters and even words. Spiral beams contain an infinite set of Laguerre-Gauss beams with a strong sequence of topological charges and radial numbers, their amplitudes and phases are tightly matched. Therefore, the problem of structural stability plays a special role for their applications. Using a combination of theory and computer simulation, supported by experiment, we ana-lyzed the structure of critical points in energy flows for two main types of spiral beams: triangular beams with zero radial number and triangular beams with complex framing of their faces with both quantum numbers. Structural stability is provided by triads of critical points, both inside and outside the triangle, which direct the light flux along the triangular generatrix and hold the framing when rotating the beam. The experiment showed that a simple triangular spiral beam turns out to be stable even with small alignment inaccuracies, whereas a complex triangular beam with a fram-ing requires careful alignment.

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Bae, Taegeun, Hanseop Kim, Jeong Hee Kim, Yong Jun Kim, Seung Hwan Lee, Byung-Joo Ham, and Junho K. Hur. "Specificity Assessment of CRISPR Genome Editing of Oncogenic EGFR Point Mutation with Single-Base Differences." Molecules 25, no. 1 (December 22, 2019): 52. http://dx.doi.org/10.3390/molecules25010052.

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In CRISPR genome editing, CRISPR proteins form ribonucleoprotein complexes with guide RNAs to bind and cleave the target DNAs with complete sequence complementarity. CRISPR genome editing has a high potential for use in precision gene therapy for various diseases, including cancer and genetic disorders, which are caused by DNA mutations within the genome. However, several studies have shown that targeting the DNA via sequence complementarity is imperfect and subject to unintended genome editing of other genomic loci with similar sequences. These off-target problems pose critical safety issues in the therapeutic applications of CRISPR technology, with particular concerns in terms of the genome editing of pathogenic point mutations, where non-mutant alleles can become an off-target with only a one-base difference. In this study, we sought to assess a novel CRISPR genome editing technique that has been proposed to achieve a high specificity by positioning the mismatches within the protospacer adjacent motif (PAM) sequence. To this end, we compared the genome editing specificities of the PAM-based and conventional methods on an oncogenic single-base mutation in the endothelial growth factor receptor (EGFR). The results indicated that the PAM-based method provided a significantly increased genome editing specificity for pathogenic mutant alleles with single-base precision.

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Janson, Lucas, Brian Ichter, and Marco Pavone. "Deterministic sampling-based motion planning: Optimality, complexity, and performance." International Journal of Robotics Research 37, no. 1 (June 22, 2017): 46–61. http://dx.doi.org/10.1177/0278364917714338.

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Probabilistic sampling-based algorithms, such as the probabilistic roadmap (PRM) and the rapidly exploring random tree (RRT) algorithms, represent one of the most successful approaches to robotic motion planning, due to their strong theoretical properties (in terms of probabilistic completeness or even asymptotic optimality) and remarkable practical performance. Such algorithms are probabilistic in that they compute a path by connecting independently and identically distributed (i.i.d.) random points in the configuration space. Their randomization aspect, however, makes several tasks challenging, including certification for safety-critical applications and use of offline computation to improve real-time execution. Hence, an important open question is whether similar (or better) theoretical guarantees and practical performance could be obtained by considering deterministic, as opposed to random, sampling sequences. The objective of this paper is to provide a rigorous answer to this question. Specifically, we first show that PRM, for a certain selection of tuning parameters and deterministic low-dispersion sampling sequences, is deterministically asymptotically optimal, in other words, it returns a path whose cost converges deterministically to the optimal one as the number of points goes to infinity. Second, we characterize the convergence rate, and we find that the factor of sub-optimality can be very explicitly upper-bounded in terms of the[Formula: see text] -dispersion of the sampling sequence and the connection radius of PRM. Third, we show that an asymptotically optimal version of PRM exists with computational and space complexity arbitrarily close to [Formula: see text] (the theoretical lower bound), where n is the number of points in the sequence. This is in contrast to the [Formula: see text] complexity results for existing asymptotically optimal probabilistic planners. Fourth, we discuss extending our theoretical results and insights to other batch-processing algorithms such as FMT*, to non-uniform sampling strategies, to k-nearest-neighbor implementations, and to differentially constrained problems. Importantly, our main theoretical tool is the [Formula: see text]-dispersion, an interesting consequence of which is that all our theoretical results also hold for low-[Formula: see text]-dispersion random sampling (which i.i.d. sampling does not satisfy). In other words, achieving deterministic guarantees is really a matter of i.i.d. sampling versus non-i.i.d. low-dispersion sampling (with deterministic sampling as a prominent case), as opposed to random versus deterministic. Finally, through numerical experiments, we show that planning with deterministic (or random) low-dispersion sampling generally provides superior performance in terms of path cost and success rate.

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Willmott, Devin, David Murrugarra, and Qiang Ye. "Improving RNA secondary structure prediction via state inference with deep recurrent neural networks." Computational and Mathematical Biophysics 8, no. 1 (March 31, 2020): 36–50. http://dx.doi.org/10.1515/cmb-2020-0002.

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AbstractThe problem of determining which nucleotides of an RNA sequence are paired or unpaired in the secondary structure of an RNA, which we call RNA state inference, can be studied by different machine learning techniques. Successful state inference of RNA sequences can be used to generate auxiliary information for data-directed RNA secondary structure prediction. Typical tools for state inference, such as hidden Markov models, exhibit poor performance in RNA state inference, owing in part to their inability to recognize nonlocal dependencies. Bidirectional long short-term memory (LSTM) neural networks have emerged as a powerful tool that can model global nonlinear sequence dependencies and have achieved state-of-the-art performances on many different classification problems.This paper presents a practical approach to RNA secondary structure inference centered around a deep learning method for state inference. State predictions from a deep bidirectional LSTM are used to generate synthetic SHAPE data that can be incorporated into RNA secondary structure prediction via the Nearest Neighbor Thermodynamic Model (NNTM). This method produces predicted secondary structures for a diverse test set of 16S ribosomal RNA that are, on average, 25 percentage points more accurate than undirected MFE structures. Accuracy is highly dependent on the success of our state inference method, and investigating the global features of our state predictions reveals that accuracy of both our state inference and structure inference methods are highly dependent on the similarity of pairing patterns of the sequence to the training dataset. Availability of a large training dataset is critical to the success of this approach. Code available at https://github.com/dwillmott/rna-state-inf.

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Perera, Kanishka, Marco Squassina, and Yang Yang. "A note on the Dancer–Fučík spectra of the fractional p-Laplacian and Laplacian operators." Advances in Nonlinear Analysis 4, no. 1 (February 1, 2015): 13–23. http://dx.doi.org/10.1515/anona-2014-0038.

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AbstractWe study the Dancer–Fučík spectrum of the fractional p-Laplacian operator. We construct an unbounded sequence of decreasing curves in the spectrum using a suitable minimax scheme. For p = 2, we present a very accurate local analysis. We construct the minimal and maximal curves of the spectrum locally near the points where it intersects the main diagonal of the plane. We give a sufficient condition for the region between them to be nonempty and show that it is free of the spectrum in the case of a simple eigenvalue. Finally, we compute the critical groups in various regions separated by these curves. We compute them precisely in certain regions and prove a shifting theorem that gives a finite-dimensional reduction in certain other regions. This allows us to obtain nontrivial solutions of perturbed problems with nonlinearities crossing a curve of the spectrum via a comparison of the critical groups at zero and infinity.

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Lai, Honggang, Yuanyue Tang, Fangzhe Ren, Zeng Li, Fengming Li, Chaoyue Cui, Xinan Jiao, and Jinlin Huang. "An Investigation into the Critical Factors Influencing the Spread of Campylobacter during Chicken Handling in Commercial Kitchens in China." Microorganisms 9, no. 6 (May 28, 2021): 1164. http://dx.doi.org/10.3390/microorganisms9061164.

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Campylobacteriosis is the most common cause of bacterial gastroenteritis worldwide. Consumption of chicken meat is considered the main route for human infection with Campylobacter. This study aimed to determine the critical factors for Campylobacter cross-contamination in Chinese commercial kitchens during chicken handling. Five commercial kitchens were visited to detect Campylobacter occurrence from 2019 to 2020. Chicken samples (n = 363) and cotton balls from the kitchen surfaces (n = 479) were collected, and total bacterial counts and Campylobacter spp. were detected. Genotypic characterization of 57 Campylobacter jejuni isolates was performed by multilocus sequence typing (MLST). In total, 77.41% of chicken carcass samples and 37.37% of kitchen surfaces showed Campylobacter spp. contamination. Before chicken preparation, Campylobacter spp. were already present in the kitchen environment; however, chicken handling significantly increased Campylobacter spp. prevalence (p < 0.05). After cleaning, boards, hands, and knives still showed high bacterial loads including Campylobacter spp., which related to poor sanitary conditions and ineffective handling practices. Poor sanitation conditions on kitchen surfaces offer greater opportunities for Campylobacter transmission. Molecular typing by MLST revealed that Campylobacter cross-contamination occurred during chicken preparation. The most prevalent sequence types, ST693 and ST45, showed strong biofilm formation ability. Consequently, sanitary condition of surfaces and biofilm formation ability of isolates were the critical points contributing to spread of Campylobacter in kitchen environment. These results provide insight into potential targeted control strategies along the farm-to-plate chain and highlight the necessity for improvements in sanitary conditions. The implementation of more effective cleaning measures should be considered to decrease the campylobacteriosis risk.

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Cho, Yunhyung. "Unimodality of Betti numbers for Hamiltonian circle actions with index-increasing moment Maps." International Journal of Mathematics 27, no. 05 (May 2016): 1650043. http://dx.doi.org/10.1142/s0129167x16500439.

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The unimodality conjecture posed by Tolman in [L. Jeffrey, T. Holm, Y. Karshon, E. Lerman and E. Meinrenken, Moment maps in various geometries, http://www.birs.ca/workshops/2005/05w5072/report05w5072.pdf ] states that if [Formula: see text] is a [Formula: see text]-dimensional smooth compact symplectic manifold equipped with a Hamiltonian circle action with only isolated fixed points, then the sequence of Betti numbers [Formula: see text] is unimodal, i.e. [Formula: see text] for every [Formula: see text]. Recently, the author and Kim [Y. Cho and M. Kim, Unimodality of the Betti numbers for Hamiltonian circle action with isolated fixed points, Math. Res. Lett. 21(4) (2014) 691–696] proved that the unimodality holds in eight-dimensional case by using equivariant cohomology theory. In this paper, we generalize the idea in [Y. Cho and M. Kim, Unimodality of the Betti numbers for Hamiltonian circle action with isolated fixed points, Math. Res. Lett. 21(4) (2014) 691–696] to an arbitrary dimensional case. We prove the conjecture in arbitrary dimension under the assumption that the moment map [Formula: see text] is index-increasing, which means that [Formula: see text] implies [Formula: see text] for every pair of critical points [Formula: see text] and [Formula: see text] of [Formula: see text], where [Formula: see text] is the Morse index of [Formula: see text] with respect to [Formula: see text].

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Seah, S., W. Spielmeyer, J. Jahier, K. Sivasithamparam, and E. S. Lagudah. "Resistance Gene Analogs within an Introgressed Chromosomal Segment Derived from Triticum ventricosum That Confers Resistance to Nematode and Rust Pathogens in Wheat." Molecular Plant-Microbe Interactions® 13, no. 3 (March 2000): 334–41. http://dx.doi.org/10.1094/mpmi.2000.13.3.334.

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A resistance (R) gene-rich 2S chromosomal segment from Triticum ventricosum contains a cereal cyst nematode (CCN; Heterodera avenae) R gene locus CreX and a closely linked group of genes (Sr38, Yr17, and Lr37) that confer resistance to stem rust (Puccinia graminis f. sp. tritici), stripe rust (P. striiformis f. sp. tritici), and leaf rust (P. recondita f. sp. tritici) when introgressed into wheat. The 2S chromosomal segment from T. ventricosum is further delineated in translocations onto chromosome 2A of bread wheat, where the rust genes are retained but not the CreX gene. Using these critical genetic stocks, we have isolated family members of R gene analogs that are associated with either the 2S segment from T. ventricosum carrying the CreX locus or the rust genes. Derivatives of the Cre3 candidate R gene sequence and a rice (Oryza sativa) R gene analog that mapped to the 2S homologous chromosome groups in wheat were used to isolate related gene sequences from T. ventricosum that contain a nucleotide binding site-leucine rich repeat domain. The potential of these gene sequences as entry points for isolating candidate genes or gene family members of the CreX or rust genes and their further applications to plant breeding are discussed.

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Poston, Rebecca, Jenny Bernstein, and Susan Braid. "Ethics and the Genome in the NICU: Stewardship from the Bedside Nurse." Neonatal Network 38, no. 5 (August 1, 2019): 286–95. http://dx.doi.org/10.1891/0730-0832.38.5.286.

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Medical technology has rapidly decreased the time and cost required to sequence, visualize, and analyze an individual's genome since the Human Genome Project (HGP) ended in April of 2003. The resulting real-time implementation and expanded use of genetic testing in clinical practice, especially in the NICU, has often left ethicists playing catch-up and providing reactive guidance rather than proactive guidance, and nurses struggling to understand their role in resolving associated legal, ethical, and social concerns. This article provides proactive guidance concerning some of the common ethical issues that are manifest in the application of genomics in the NICU as well as practical resources for navigating these conversations with parents and families. Clinical scenarios illustrate key points of consideration for NICU nurses engaged with challenging issues related to genomics in the NICU.

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Journal articles on the topic 'Critical sequence of points'

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