bluuebunny/crossref_metadata_2025 huggingface dataset:
Monosomy and trisomy induced by the r-x1 deletion in maize, and associated effects on endosperm development
Authors: Lin Bor-Yaw , Coe Jr. E. H.
Published: November 2014

The r-x1 deficiency on chromosome 10 of maize conditions nondisjunction during embryo sac development. Variations in kernel size associated with r-x1 are found to be correlated with aneuploidy, both monosomy and trisomy, in the embryo. Among a sample of 70 normal-sized kernels only 10% had aneuploid embryos (4 monosomies, 3 trisomies), while 41 selected small kernels had 44% aneuploids (10 monosomies, 1 double monosomic, 7 trisomics) and 32 medium kernels also had 44% aneuploids (1 monosomic, 12 trisomics, 1 triple trisomic). On the assumption that reduced kernel size is due to aneuploidy in the endosperm following nondisjunction at one of the embryo sac mitoses, the observed proportion of hypoploid:hyperploid:euploid embryos among small kernels is inconsistent with nondisjunction at the first or third mitoses but fits well the expectation for nondisjunction occurring at the second mitosis. Nondisjunction at this division leads to both corresponding and noncorresponding constitutions between the embryo, and endosperm.Key words: Zea, aneuploidy, embryo sac, nondisjunction.
Cytogenetics of Blattella germanica: comparison of an insecticide-resistant and an insecticide-susceptible field strain
Authors: Ross Mary H.
Published: November 2014

Meiotic chromosomes of a cockroach field strain that is highly resistant to several insecticides were compared with those of a susceptible field strain. The resistant strain was characterized by extensive autosome–autosome associations. They resulted in fragmentation, deletions, and insertion or attachment of segments in novel positions. The distribution pattern of chiasma frequency was also aberrant. One individual was heterozygous for an interchange between chromosomes 6 and 12. Properties of the susceptible strain were generally similar to those described earlier from a laboratory susceptible strain, except that a terminal knob on chromosome 4 was frequently present.Key words: Blattella, cockroach, chromosome, resistance.
A chromosome marker for the early detection of mouse embryos carrying the neural tube defect mutation splotch
Authors: Kapron-Brás C. M. , Vekemans M. J. J. , Trasler D. G.
Published: November 2014

A major problem in the study of neural tube defects caused by the splotch (Sp) gene in the mouse has been the identification of gene carriers or potentially affected embryos at an early stage of development, since the gene's effects become visible only late in gestation or after birth. To aid in the identification of Sp carriers, we have developed a technique using a Robertsonian translocation as a marker for this gene. The accuracy of identification is reduced by crossing-over between the Sp locus and the centromere but, because of crossover suppression in the particular cross used, there was only 23.2% recombination compared with the known map distance of 36%. Paternal age had no effect on the frquency of recombination, but individual males differed significantly in the degree of crossover suppression.Key words: mouse, embryo, neural tube defects, marker, chromosome.
Genetic load and heterozygosity in the Pinaceae
Authors: Mitchell-Olds Thomas , Guries Raymond P.
Published: November 2014

Lethal genetic load might be caused by a few lethal genes or by large numbers of mildly deleterious polygenes. The extent of this lethal load can be quantified as the number of "lethal equivalents" in each individual. If there are large numbers of deleterious genes scattered throughout the genome then we might expect a correlation between the number of lethal equivalents and the level of heterozygosity at isozyme marker loci. Using data from 52 isozyme loci, we estimated this correlation on 68 individuals in four conifer species (Pinus ponderosa Laws., Pinus contorta Dougl., Picea glauca (Moench) Voss., and Pseudotsuga menziesii (Mirb.) Franco). No significant correlation was detected. We interpret this consistent result in four species as indicating that lethal equivalents do not represent large numbers of mildly deleterious polygenes in these forest trees.Key words: genetic load, lethal equivalent, Pinaceae, heterozygosity.
Differentiation of H genomes in the genus Critesion: evidence from synthetic hybrids involving Elymus and Critesion and one natural hybrid of C. violaceum and C. bogdanii
Authors: Wang Richard R. -C. , Hsiao C.
Published: November 2014

Hybrids of Elymus canadensis (2n = 28; SSHH) × Critesion californicum (2n = 14) and E. canadensis × C. bulbosum (2n = 14) were synthesized at relative frequencies of 11.8 and 0.3%, respectively, by the aid of embryo rescue techniques. A natural hybrid was identified as C. violaceum × C. bogdanii (2n = 14) by a combination of karytotype analysis and plant morphology. Gross spike morphology of the hybrids was intermediate to that of the parents. Meiotic chromosome pairings in these hybrids suggested that the genome of C. californicum and C. bogdanii is more or less homologous with one of the two genomes of E. canadensis. Genomes of C. violaceum and C. bulbosum appeared to be different from each other and from those in C. bogdanii and C. californicum. Based on the data in this study and others, the degree of genome differentiation among some Critesion and some Elymus species containing the H genome was examined and discussed. The symbol H is proposed for the genome in C. bogdanii and C. californicum, Hv for C. violaceum, Hb for C. bulbosum, and Hc for C. chilense.Key words: interspecific hybrids, synapsis, phylogeny, Hordeum, Elymus, Critesion.
Use of Neurospora Spore killer strains to obtain centromere linkage data without dissecting asci
Authors: Perkins David D. , Raju Namboori B. , Pollard Virginia C. , Campbell Joseph L. , Richman Adam M.
Published: November 2014

Use of a centromere-linked Spore killer gene Sk reduces manyfold the labor involved in obtaining tetrad data that would otherwise require ordered dissection of intact linear eight-spored asci. Heterozygous crosses are made for Spore killer (SkK × SkS) and for markers to be tested. In such crosses only SkK ascospores survive. The four viable (SkK) and four aborted (SkS) ascospores of each ascus are ejected from the perithecium as a physically disordered group. The four surviving SkK ascospores of individual asci are germinated and scored. SkK segregates from SkS at the first meiotic division. If both marker alleles are represented in the surviving products, they must therefore have segregated from one another at the second division. Four-spore (Fsp) genes have been used to eliminate one postmeiotic nuclear division, so that only two ascospores per ascus need to be scored. The Spore killer method has been useful for mapping closely linked genes in centromere regions, for identifying genes that are far out on chromosome arms, for obtaining information on meiotic crossing-over, and for comparing linkages in different species.Key words: tetrad analysis, centromere mapping, Spore killer, Neurospora.
Genetic and demographic effects of single wild-type immigrants on a mutant population of Tribolium castaneum
Authors: Delgado Michael A. , Englert DuWayne C.
Published: November 2014

The effects of single wild-type immigrants on populations of Tribolium castaneum initially homozygous for the antennapedia (ap) allele were examined in reference to gene frequencies and age structures. One population received a wild-type male, another received a wild-type female, and the control population received no wild-type immigrant. The rate of increase in the wild-type gene frequency was significantly higher in the female immigrant population. Rapid increase in heterozygosity for this population resulted in a higher average number of adults than for the other two treatment groups. No significant differences in the numbers of larvae and pupae were observed. Results indicated increased larval survivability to be the major factor in establishment of the wild-type gene and the sex of the immigrant in the rate of increase.Key words: Tribolium, population, selection, immigration, antennapedia.
A new method for producing homozygous duplications in maize
Authors: Carlson W. R. , Curtis C.
Published: November 2014

Translocations between the B chromosomes of maize and standard (A) chromosomes have been widely used to manipulate the dosage of A chromosome segments. The B chromosome frequently undergoes nondisjunction at the second pollen mitosis as part of its normal pattern of inheritance. BA chromosomes also undergo nondisjunction and, therefore, are used to produce duplications and deficiencies of A-chromatin. Duplications are useful in gene dosage studies and some may have agronomic value if they are associated with useful phenotypes. However, duplications produced by BA nondisjunction cannot be easily maintained during propagation. The BA undergoes nondisjunction each generation, destabilizing its inheritance. A new method is presented here for systematically duplicating segments of the maize genome using B–A translocations. The method uses meiotic segregation rather than nondisjunction to produce duplications. It employs AB chromosomes instead of BA chromosomes. As a test of the method, homozygous duplications (segmental tetrasomics) were constructed for a region on chromosome 3 and for another region on chromosome 9.Key words: maize, B chromosome, duplication.
Nature of sterility and mechanism of the evolution of higher ploidy in Solanum section Solanum (Maurella)
Authors: Ganapathi A. , Rao G. R.
Published: November 2014

Cytomorphology of solanum nigrum L. (2n = 6x = 72) and S. americanum Mill. (2n = 2x = 24) was studied. Crosses were made between these two species, but crosses were successful only when the higher ploidy form was used as the maternal parent. The F1 hybrid was a tetraploid (2n = 4x = 48) and showed highly irregular meiosis. It did not set fruit either on selfing or on open pollination. A fertile octoploid branch spontaneously grew from the sterile hybrid. The octoploid had regular meiosis and produced several fruits with viable seeds. Pollen stainability was 82%. From cytological studies of the tetraploid and its amphiploid, it is concluded that hybridization and polyploidy have played a significant role in the origin and evolution of higher chromosomal forms of Solanum section Solanum (Maurella).Key words: Solanum, polyploid, sterility.
Heat shock induced changes in the gene expression of terminally differentiating avian red blood cells
Authors: Atkinson Burr G. , Dean Rob L. , Blaker Timothy W.
Published: November 2014

Reticulocytes, purified from the blood of quail and chickens recovering from anaemia, respond to heat shock by (i) the new and (or) enhanced synthesis of heat-shock protein (HSPs) with relative molecular masses of > 400 000, 90 000, 70 000, and 26 000 (quail) or 24 000 (chicken) and (ii) the depressed synthesis of many proteins normally produced at a control temperature. The synthesis of these HSPs is noncoordinate since the expression of each protein depends upon the particular temperature and duration of the time at that temperature. Separation of proteins from quail reticulocytes into Triton X-100 soluble and insoluble fractions demonstrates that the 70 000 and 26 000 Da HSPs are found in both fractions, whereas the > 400 000 and 90 000 Da HSPs are located only in the detergent-soluble fraction. Triton X-100 fractionation also reveals that there are three isoelectric variants of the 70 000 Da HSP and that they are constitutively synthesized and selectively partitioned between cellular compartments. Heat shock induced synthesis of the 90 000, 70 000, and 26 000 Da quail HSPs is prevented by actinomycin D, while enhanced synthesis of the > 400 000 Da HSP is unaffected by this inhibitor. These results demonstrate that nucleated, terminally differentiating avian red blood cells are capable of responding to heat stress by rapid changes in their highly restricted "program" of gene expression.Key words: heat shock, heat-shock proteins, reticulocytes, avian, red blood cells, gene expression.
Murine plasmacytomas constitute a class of natural heat-shock variants in which the major inducible hsp-68 gene is not expressed
Authors: Aujame L.
Published: November 2014

Analysis of the heat-shock response in murine plasmacytomas reveals that, as demonstrated previously for the MPC-11 cell line, the genes coding for the 68-kilodalton heat-shock protein (hsp-68) are not expressed upon heat shock or sodium arsenite treatment. Noninduction is unique to the normally coordinated set of three hsp-68 genes since at least two other heat-shock protein genes (hsp-70 and hsp-89) are properly induced. No other lymphoid cell line was found to possess silent hsp-68 genes. Cell lines examined included a T lymphoma, a pre-B lymphocyte, and a non-B–non-T tumor cell line, as well as an Ig-nonproducing myeloma of undetermined differentiated status. Nonexpression is strain-independent as observed in BALB/c and C3H plasmacytomas. Based on S1 nuclease analysis using a cloned genomic hsp-68 probe, nonexpression is caused by the absence of hsp-68 mRNA following heat shock. A time-course experiment suggests that rapid degradation of mRNA does not occur, implying that the block is most likely at the transcriptional level. Southern blot analysis does not indicate any minor deletions around the region of transcription initiation, at least in the probed hsp-68 gene. These results suggest that the absence of hsp-68 gene expression may be a reflection of the differentiated and (or) transformed state of murine plasma cells, possibly through the absence or deregulation of a regulatory factor required for induction of heat-shock genes.Key words: heat shock, gene expression, plasmacytoma, mouse.
Temperature-stress response in maize: a comparison of several cultivars
Authors: Yacoob Reza K. , Filion W. Gary
Published: November 2014

The protein synthetic response to a heat (28–41 °C) and a cold (28–4 °C) shock was studied in seedlings from 10 cultivars of maize with varying levels of cold tolerance. This response was compared by fluorography of one-dimensional polyacrylamide gels and immunoblot analysis. We utilized polyclonal antibodies against the 18 000 dalton (Da) heat-shock protein and the 73 000–89 000 Da heat-shock protein complex from Oh43 maize seedlings to ascertain antigenic similarity of these polypeptides. The heat-shock response varied in the numbers and relative molecular masses of the heat-shock proteins. Only three polypeptides appeared to be conserved across cultivars: a 93 000, 71 000, and 18 000 Da polypeptide. The cold-shock response varied from none to a dramatically altered pattern in a few cultivars. Thus, the heat- and cold-shock responses in these cultivars of corn differ in the types of polypeptides that are induced. All cultivars showed varying degrees of cross-reactivity when probed with the anti 18 000 Da heat-shock protein antibody. The inbred lines appeared to respond more to a cold shock than the hybrid lines but there was little relationship between the cold tolerance and the induction of a cold-shock response. Two of the cultivars demonstrated unique binding to a higher molecular weight polypeptide under control (28 °C) conditions. These data suggest that within species variation in both number and relative molecular weight of thermal stress polypeptides (heat and cold) is a function of genotype.Key words: heat shock, cold shock, cold tolerance, maize, gene expression.
A novel dynamical community detection algorithm based on weighting scheme
Authors: Li Ju , Yu Kai , Hu Ke
Published: November 2014

Network dynamics plays an important role in analyzing the correlation between the function properties and the topological structure. In this paper, we propose a novel dynamical iteration (DI) algorithm, which incorporates the iterative process of membership vector with weighting scheme, i.e. weighting W and tightness T. These new elements can be used to adjust the link strength and the node compactness for improving the speed and accuracy of community structure detection. To estimate the optimal stop time of iteration, we utilize a new stability measure which is defined as the Markov random walk auto-covariance. We do not need to specify the number of communities in advance. It naturally supports the overlapping communities by associating each node with a membership vector describing the node's involvement in each community. Theoretical analysis and experiments show that the algorithm can uncover communities effectively and efficiently.
Lattice hydrodynamic model for bidirectional pedestrian flow with the consideration of pedestrian density difference
Authors: Zhou Jie , Shi Zhong-Ke
Published: November 2014

Considering the effect of density difference, an extended lattice hydrodynamic model for bidirectional pedestrian flow is proposed in this paper. The stability condition is obtained by the use of linear stability analysis. It is shown that the stability of pedestrian flow varies with the reaction coefficient of density difference. Based on nonlinear analysis method, the Burgers, Korteweg–de Vries (KdV) and modified Korteweg–de Vries (MKdV) equations are derived to describe the triangular shock waves, soliton waves and kink–antikink waves in the stable, metastable and unstable regions, respectively. The results show that jams may be alleviated by considering the effect of density difference. The findings also indicate that in the process of building and subway station design, a series of auxiliary facilities should be considered in order to alleviate the possible pedestrian jams.
Review on photonic crystal coatings for scintillators
Authors: Knapitsch Arno , Lecoq Paul
Published: November 2014

The amount of light and its time distribution are key factors determining the performance of scintillators when used as radiation detectors. However most inorganic scintillators are made of heavy materials and suffer from a high index of refraction which limits light extraction efficiency. This increases the path length of the photons in the material with the consequence of higher absorption and tails in the time distribution of the extracted light. Photonic crystals are a relatively new way of conquering this light extraction problem. Basically they are a way to produce a smooth and controllable index matching between the scintillator and the output medium through the nanostructuration of a thin layer of optically transparent high index material deposited at the coupling face of the scintillator. Our review paper discusses the theory behind this approach as well as the simulation details. Furthermore the different lithography steps of the production of an actual photonic crystal sample will be explained. Measurement results of LSO scintillator pixels covered with a nanolithography machined photonic crystal surface are presented together with practical tips for the further development and improvement of this technique.
Degenerate Grazing Bifurcations in a Simple Bilinear Oscillator
Authors: Yi Tingting , Du Zhengdong
Published: November 2014

Degenerate grazing bifurcation occurring in a simple bilinear oscillator, namely the limit discontinuous case of the smooth and discontinuous (SD) oscillator, is investigated by numerical simulations. The unperturbed system has a saddle-like singularity at the origin with two periodic orbits grazing at the same point. The matrix in the leading-order truncation of the Poincaré map at a grazing bifurcation for either of the two periodic orbits has a zero eigenvalue. Our numerical experiments suggest that the near-grazing dynamics are much more complicated than previously found. The results obtained in this paper is expected to be useful in developing analytical methods of this type of degenerate grazing bifurcations.
Is that Really Hidden? The Presence of Complex Fixed-Points in Chaotic Flows with No Equilibria
Authors: Pham Viet-Thanh , Jafari Sajad , Volos Christos , Wang Xiong , Golpayegani S. Mohammad Reza Hashemi
Published: November 2014

In this letter we investigate the role of complex fixed-points in finding hidden attractors in chaotic flows with no equilibria. If these attractors could be found by starting the trajectory in the neighborhood of complex fixed-points, maybe it would be better not to call them hidden.
Bifurcation Results for Traveling Waves in Nonlinear Magnetic Metamaterials
Authors: Agaoglou M. , Rothos V. M. , Frantzeskakis D. J. , Veldes G. P. , Susanto H.
Published: November 2014

In this work, we study a model of a one-dimensional magnetic metamaterial formed by a discrete array of nonlinear resonators. We focus on periodic and localized traveling waves of the model, in the presence of loss and an external drive. Employing a Melnikov analysis we study the existence and persistence of such traveling waves, and study their linear stability. We show that, under certain conditions, the presence of dissipation and/or driving may stabilize or destabilize the solutions. Our analytical results are found to be in good agreement with direct numerical computations.
Note on Nonejective Topological Fractals on Peano's Continua
Authors: Andres Jan , Górniewicz Lech
Published: November 2014

The Browder nonejective fixed point theorem [Browder, 1965] will be generalized in two directions. One generalization will be then applied to the existence of nonejective topological multivalued fractals on Peano's continua. An illustrative example will be supplied.
On the Ultimate Dynamics of the Four-Dimensional Rössler System
Authors: Starkov Konstantin E.
Published: November 2014

In this paper, we construct the polytope which contains all compact ω-limit sets of the four-dimensional Rössler system which is a generalization of the hyperchaotic Rössler system for the case of positive parameters. Further, we find a few three-dimensional planes containing all compact ω-limit sets for bounded positive half-trajectories located in some subdomains in the half-space z > 0. Besides, we analyze one case in which all compact ω-limit sets in the half-space z > 0 are contained in one three-dimensional plane. Our approach is based on a combination of the LaSalle theorem and the extreme-based localization method of compact invariant sets.
Carbon Dioxide Flooding Technology Research and Field Test in Liuzan North Block
Authors: Zhang Hanshi , Luo Pingya , Sun Lei , Fu Zhijun
Published: November 2014

The fault roots of Liuzan north block in Jidong oilfield of China have been long-term explored by solution gas drive. Recently, oil production declined rapidly because of shortage of formation energy and needing high water injection pressure. Carbon dioxide injection pressure is found to be generally low, and CO 2 has good solubility in crude oil to supply formation energy and achieve high oil recovery efficiency. In this work, a pilot program of CO 2 EOR technology was carried out. The slim tube test results showed that the minimal miscible pressure of Liuzan north block was 28.28 MPa. The injection parameters were optimized by numerical simulation method: the injection method was continuous, the slug size was 0.2 HCPV and the EOR efficiency was 7.23%. After two months of gas injection field test, the formation pressure of two gas injectors just increased by 14.02 MPa and 2.98 MPa, respectively, indicating that carbon dioxide could supply the formation energy effectively. 16 months after gas injection, the CO 2 injection amount was 14640 t, and the oil increment was 16424 t. The present work demonstrates the potential applicability of CO 2 flooding technology from high water injection reservoirs.
Component, Microstructure and Simulation Calculation Study of Bimetallic Pt-Cu Alloys Towards Catalyzing Methanol Oxidation Reaction
Authors: Wei Shenying , Gao Huaizhi , Li Haibo , Li Rui , Liu Jifeng
Published: November 2014

Three Pt - Cu alloys ( Pt 0.3 Cu 0.7, Pt 0.5 Cu 0.5, and Pt 0.7 Cu 0.3) with different Cu contents were synthesized by adjusting the Pt / Cu precursor ratio, and their electrocatalytic activities for methanol oxidation reaction (MOR) were systematically studied. Component and microstructure study revealed that the relationship between the lattice parameters and Cu content followed the Vegard's law. Electrochemistry measurement showed that the MOR catalytic activity for Pt - Cu alloys displayed a dependency on the Cu content, and it decreased following: Pt 0.3 Cu 0.7 > Pt 0.5 Cu 0.5 > Pt 0.7 Cu 0.3. Among the three Pt - Cu alloys, the Pt 0.3 Cu 0.7 alloy exhibited the highest oxidation current density and best CO tolerance activity. Density functional theory simulation calculation, taking into account the shrinking of Pt - Cu alloy's lattice after Cu incorporation, confirmed that the adsorption energy of CO also displayed a dependency on the Cu content in Pt - Cu alloys, and it increased following: Pt 0.3 Cu 0.7 < Pt 0.5 Cu 0.5 < Pt 0.7 Cu 0.3 < Pt , which could rationally explain the best CO tolerance ability for the Pt 0.3 Cu 0.7.
Numerical estimates for the regularization of nonautonomous ill-posed problems
Authors: Fury Matthew A.
Published: November 2014

The regularization of ill-posed problems has become a useful tool in studying initial value problems that do not adhere to certain desired properties such as continuous dependence of solutions on initial data. Because direct computation of the solution becomes difficult in this situation, many authors have alternatively approximated the solution by the solution of a closely defined well posed problem. In this paper, we demonstrate this process of regularization for nonautonomous ill-posed problems including the backward heat equation with a time-dependent diffusion coefficient. In the process, we provide two different approximate well posed models and numerically compare convergence rates of their solutions to a known solution of the original ill-posed problem.
Intensive up-conversion photoluminescence of Er3+-doped Bi7Ti4NbO21 ferroelectric ceramics and its temperature sensing
Authors: Zou Hua , Li Jun , Cao Qiufeng , Wang Xusheng , Hui Xinwei , Li Yanxia , Yu Yao , Yao Xi
Published: November 2014

The intensive up-conversion (UC) photoluminescence and temperature sensing behavior of Er 3+-doped Bi 7 Ti 4 NbO 21( BTN ) ferroelectric ceramics prepared by a conventional solid-state reaction technique have been investigated. The X-ray diffraction and field emission scanning electron microscope analyses demonstrated that the Er 3+-doped BTN ceramics are single phase and uniform flake-like structure. With the Er 3+ ions doping, the intensive UC emission was observed without obviously changing the properties of ferroelectric. The optimal emission intensity was obtained when Er doping level was 15 mol.%. The temperature sensing behavior was studied by fluorescence intensity ratio (FIR) technique of two green UC emission bands, and the experimental data fitted very well with the function of temperature in a range of 133–573 K. It suggested that the Er 3+-doped BTN ferroelectric ceramics are very good candidates for applications such as optical thermometry, electro-optical devices and bio-imaging ceramics.
Studies of permittivity and permeability of dielectric matrix with cuboid metallic inclusions in different orientations
Authors: Wu W. M. , Njoku C. C. , Whittow W. G. , Zagoskin A. M. , Kusmartsev F. V. , Vardaxoglou J. C.
Published: November 2014

In this paper, we investigate the possibility of using the heterogeneous materials, with cuboid metallic inclusions inside a dielectric substrate (host) to control the effective permittivity. We find that in the gigahertz range, such a material demonstrates a significantly larger permittivity compared to the pure dielectric substrate. Three principal orientations of microscale cuboid inclusions have been taken into account in this study. The highest permittivity is observed when the orientation provides the largest polarization (electric dipole moment). The detrimental side effect of the metallic inclusion, which leads to the decrease of the effective magnetic permeability, can be suppressed by the proper choice of shape and orientation of the inclusions. This choice can in fact reduce the induced current and hence maximize the permeability. The dissipative losses are shown to be negligible in the relevant range of frequencies and cuboid dimensions.
Holocene climate variability in the Labrador Sea
Authors: Hoogakker Babette A. A. , McCave I. Nick , Elderfield Henry , Hillaire-Marcel Claude , Simstich Johannes
Published: November 2014

Formation of Labrador Sea Water proper commenced about 7000 years ago during the Holocene interglacial. To test whether fresher surface water conditions may have inhibited Labrador Sea Water convection during the early Holocene we measured planktonic foraminiferal (
Globigerina bulloides
) oxygen isotopes (δ
18
O) and Mg/Ca ratios at Orphan Knoll (cores HU91-045-093 and MD95-2024, 3488 m) in the Labrador Sea to reconstruct shallow subsurface summer conditions (temperature and seawater δ
18
O). Lighter foraminiferal δ
18
O values are recorded during the early Holocene between 11000 and 7000 years ago. Part of these lighter foraminiferal δ
18
O values can be explained by increased calcification temperatures. Reconstructed seawater δ
18
O values were, however, still on average 0.5‰ lighter compared with those of recent times, confirming that fresher surface waters in the Labrador Sea were probably a limiting factor in Labrador Sea Water formation during the early Holocene.
Chronology, petrogenesis and heat sources for successive Carboniferous magmatic events in the Southern–Central Variscan Vosges Mts (NE France)
Authors: Tabaud Anne-Sophie , Janoušek Vojtěch , Skrzypek Etienne , Schulmann Karel , Rossi Philippe , Whitechurch Hubert , Guerrot Catherine , Paquette Jean-Louis
Published: November 2014

Plutonic bodies of the Central and Southern Vosges Mts can be assigned to two major early Carboniferous magmatic events: a Visean Mg–K event (
c.
345 and 340–336 Ma) and a younger S-type event (329–322 Ma). New petrological, geochemical and Sr–Nd isotopic data highlight the existence of two groups of Mg–K intrusions that might be related to the nature of their primary magma sources; that is, CHUR-like and enriched mantle, which interacted with juvenile and mature crustal material, respectively. The differences between these two groups are explained by a geodynamic scenario involving deep subduction and relamination of the Saxothuringian continental crust under the Moldanubian continent. The relaminated radiogenic Saxothuringian material is thought to have been responsible for dehydration melting of both subducted crust and underlying metasomatized mantle, thereby generating the Mg–K magma subsequently emplaced at middle crustal depth. During their ascent, the mafic magmas interacted with crustally derived felsic melts. Significantly later (
c
. 10–15 myr) a widespread mid-crustal anatexis occurred, generating voluminous granite intrusions from mixed crustal sources (paragneisses and/or immature felsic–intermediate metaigneous rocks mixed with Mg–K plutons). The principal heat source for such a major melting event is related to the presence of Mg–K plutons rich in heat-producing elements, which were responsible, after the time lag specified, for a temperature increase at mid-crustal levels by
in situ
radiogenic heat production. The current study underlines the importance of deep continental crust subduction and relamination for the magmatism and development of collisional orogens.

Supplementary material:

Analytical methods and data, and supplementary figures, are available at
http://www.geolsoc.org.uk/SUP18795
.
Polygonal feeder tubes filled with hydroclasts: a new volcanic lithofacies marking shoreline subaerial–submarine transition
Authors: Perez-Torrado F. J. , Gimeno D. , Aulinas M. , Cabrera M. C. , Guillou H. , Rodriguez-Gonzalez A. , Gisbert G. , Fernandez-Turiel J. L.
Published: November 2014

This paper describes for the first time a new lithofacies that formed in the passage zone during the construction of pahoehoe lava-fed deltas in the north and NE coastal areas of Gran Canaria (Canary Islands, Atlantic Ocean). These lava-fed deltas, which are Pliocene in age, present similar lithofacies associations to those previously described in the literature, except for two distinct features: low abundance of hyaloclastites and a new lithofacies in the passage zone. This new lithofacies, which we propose to name ‘polygonal feeder tubes filled with hydroclasts’, comprises metre-scale lava feeder tubes with decimetre-scale coherent poorly vesicular and aphanitic rinds of polygonal morphology, filled with closely packed hydroclasts generated
in situ
. It represents the first stage in the interaction between seawater and thick lava flows entering the sea under the influence of a tidal regime, thus marking sea level. This lithofacies should be easily recognizable in ancient successions, and thus represents a useful marker of palaeoshorelines.

Supplementary material:

Sample preparation and sample geochemistry are available at
http://www.geolsoc.org.uk/SUP18785
.
Global stone heritage: Larvikite, Norway
Authors: Heldal Tom , Meyer G. B. , Dahl R.
Published: November 2014

Larvikite is a peculiar and unique monzonitic rock originating in the Carboniferous–Permian Oslo Rift, SE Norway. The blue iridescence in the feldspar crystals made the rock particularly attractive as ornamental stone, and since the start of industrial scaled production in 1884, the use of larvikite has reached every corner of the global community. With resources for hundreds of years, the region will produce larvikite blocks far into the future. The production of larvikite has changed significantly during the last decades, towards more sustainable production finding new applications and markets for excess rock in the quarries. The significance of larvikite in the global market has also created a wider appreciation of the rock in the Norwegian society, acknowledging the rich history of larvikite production and use.
Villamayor Stone (Golden Stone) as a Global Heritage Stone Resource from Salamanca (NW of Spain)
Authors: Garcia-Talegón J. , Iñigo A. C. , Alonso-Gavilán G. , Vicente-Tavera S.
Published: November 2014

Villamayor Stone (VS) is an arkosic stone and is known by several names: (i) VS because the quarries are located in Villamayor de Armuña village (Salamanca, Spain); (ii) Golden Stone due to its patina, which gives the stone a ochreous/golden colour; (iii) Franca Stone is known locally and in historical documents. VS has several varieties ranging from channel to floodplain facies. In this work, we have selected three varieties. VS was quarried and used in the construction of Romanesque monuments such as the Old Cathedral, Gothic monuments including the New Cathedral and the University façade, and Baroque monuments, notably the Main Square. Also, VS was used in the reconstruction of the Roman Bridge (Salamanca, Spain). Currently, VS is quarried by a small number of family businesses, using traditional methods for cladding façades of new buildings. Unfortunately, part of the construction sector went bankrupt in the 2008 crisis. However, VS is still the main stone used in the city of Salamanca for the restoration of monuments, even though used in relatively small quantities in comparison with usage before the economic crisis. It is thus of great importance for future generations that their quarries and the craft of masonry be protected. This work proposes that VS should be designated as a Global Heritage Stone Resource.
Characteristics of Lake Chad Level Variability and Links to ENSO, Precipitation, and River Discharge
Authors: Okonkwo Churchill , Demoz Belay , Gebremariam Sium
Published: November 2014

This study used trend, correlation, and wavelet analysis to characterize Lake Chad (LC) level fluctuations, river discharge, El Niño Southern Oscillation (ENSO), and precipitation regimes and their interrelationships. Linear correlation results indicate a negative association between ENSO and LC level, river discharge and precipitation. Trend analysis shows increasing precipitation in the Lake Chad Basin (LCB) but decreasing LC level. The mode of interannual variability in LC level, rainfall, and ENSO analyzed using wavelet analysis is dominated by 3-4-year periods. Results show that variability in ENSO could explain only 31% and 13% of variations in LC level at Kindjeria and precipitation in the northern LCB, respectively. The wavelet transform coherency (WTC) between LC level of the southern pool at Kalom and ENSO is statistically significant at the 95% confidence level and phase-locked, implying a cause-and-effect association. These strong coherencies coincide with the La Niña years with the exception of 1997-1998 El Niño events. The WTC shows strong covariance between increasing precipitation and LC level in the northern pool at a 2- to 4-year band and 3- to 4-year band localized from 1996 to 2010. Implications for water resource planning and management are discussed.
The Impact of the Introduction of MELD on the Dynamics of the Liver Transplantation Waiting List in São Paulo, Brazil
Authors: Chaib Eleazar , Massad Eduardo , Varone Bruno Butturi , Bordini Andre Leopoldino , Galvão Flavio Henrique Ferreira , Crescenzi Alessandra , Filho Arnaldo Bernal , D’Albuquerque Luiz Augusto Carneiro
Published: November 2014

Until July 15, 2006, the time on the waiting list was the main criterion for allocating deceased donor livers in the state of São Paulo, Brazil. After this date, MELD has been the basis for the allocation of deceased donor livers for adult transplantation. Our aim was to compare the waitlist dynamics before MELD (1997–2005) and after MELD (2006–2012) in our state. A retrospective study was conducted including the data from all the liver transplant candidate waiting lists from July 1997 to December 2012. The data were related to the actual number of liver transplantations (Tr), the incidence of new patients on the list (I), and the number of patients who died while being on the waitlist (D) from 1997 to 2005 (the pre-MELD era) and from 2006 to 2012 (the post-MELD era). The number of transplantations from 1997 to 2005 and from 2006 to 2012 increased nonlinearly, with a clear trend to levelling to equilibrium at approximately 350 and 500 cases per year, respectively. The implementation of the MELD score resulted in a shorter waiting time until liver transplantation. Additionally, there was a significant effect on the waitlist dynamics in the first 4 years; however, the curves diverge from there, implying a null long-range effect on the waitlist by the MELD scores.
Nurse Scheduling Using Genetic Algorithm
Authors: Leksakul Komgrit , Phetsawat Sukrit
Published: November 2014

This study applied engineering techniques to develop a nurse scheduling model that, while maintaining the highest level of service, simultaneously minimized hospital‐staffing costs and equitably distributed overtime pay. In the mathematical model, the objective function was the sum of the overtime payment to all nurses and the standard deviation of the total overtime payment that each nurse received. Input data distributions were analyzed in order to formulate a simulation model to determine the optimal demand for nurses that met the hospital’s service standards. To obtain the optimal nurse schedule with the number of nurses acquired from the simulation model, we proposed a genetic algorithm (GA) with two‐point crossover and random mutation. After running the algorithm, we compared the expenses and number of nurses between the existing and our proposed nurse schedules. For January 2013, the nurse schedule obtained by GA could save 12% in staffing expenses per month and 13% in number of nurses when compare with the existing schedule, while more equitably distributing overtime pay between all nurses.
Interlamellar Space Configuration under Variable Environmental Conditions in the Case of Ni‐Exchanged Montmorillonite: Quantitative XRD Analysis
Authors: Ammar Marwa , Oueslati Walid , Chorfi Nejmeddine , Ben Rhaiem Hafsia
Published: November 2014

Interlamellar space organization of low‐charge montmorillonite was studied by modeling of X‐ray diffraction (XRD) patterns recorded under controlled relative humidity (RH) conditions on Ni saturated specimens. The quantitative XRD investigation, based on an indirect method consisting of the comparison of experimental reflections with the other calculated from structural models, is used to characterize eventual nanostructural changes along c* axis of Ni‐exchanged montmorillonite. This method allowed us to determine, respectively, the relative layer types contribution, the layer thickness, nanoconfiguration of the interlamellar space, and position, amount, and organization of water molecules and exchangeable cations. Obtained theoretical models exhibit heterogeneous hydration state which is the dominating character detected all over studied cycles. Along RH cycle a modification in the main structure of the host materials is performed and the presence of a mixed layer structure (MLS) is noted. The hydration hysteresis at the low and the high RH range can be explained by fluctuations in the water retention mechanism and hydration heterogeneities created within the smectite crystallite.
A New Method for Solving Supervised Data Classification Problems
Authors: Shabanzadeh Parvaneh , Yusof Rubiyah
Published: November 2014

Supervised data classification is one of the techniques used to extract nontrivial information from data. Classification is a widely used technique in various fields, including data mining, industry, medicine, science, and law. This paper considers a new algorithm for supervised data classification problems associated with the cluster analysis. The mathematical formulations for this algorithm are based on nonsmooth, nonconvex optimization. A new algorithm for solving this optimization problem is utilized. The new algorithm uses a derivative-free technique, with robustness and efficiency. To improve classification performance and efficiency in generating classification model, a new feature selection algorithm based on techniques of convex programming is suggested. Proposed methods are tested on real-world datasets. Results of numerical experiments have been presented which demonstrate the effectiveness of the proposed algorithms.
Virtual Sensor for Calibration of Thermal Models of Machine Tools
Authors: Dementjev Alexander , Hensel Burkhard , Kabitzsch Klaus , Kauschinger Bernd , Schroeder Steffen
Published: November 2014

Machine tools are important parts of high-complex industrial manufacturing. Thus, the end product quality
strictly depends on the accuracy of these machines, but they are prone to deformation caused by their own heat. The deformation needs to be compensated in order to assure accurate production. So an adequate model of the high-dimensional thermal deformation process must be created and parameters of this model must be evaluated. Unfortunately, such parameters are often unknown and cannot be calculated a priori. Parameter identification during real experiments is not an option for these models because of its high engineering and machine time effort. The installation of additional sensors to measure these parameters directly is uneconomical. Instead, an effective calibration of thermal models can be reached by combining real and virtual measurements on a machine tool during its real operation, without additional sensors installation. In this paper, a new approach for thermal model calibration is presented. The expected results are very promising and can be recommended as an effective solution for this class of problems.
Expression, Purification, and Functional Analysis of Novel RelE Operon fromX. nematophila
Authors: Rathore Jitendra Singh , Gautam Lalit Kumar
Published: November 2014

Bacterial toxin-antitoxin (TA) complexes induce programmed cell death and also function to relieve cell from stress by various response mechanisms.Escherichia coliRelB-RelE TA complex consists of a RelE toxin functionally counteracted by RelB antitoxin. In the present study, a novel homolog of RelE toxin designated as Xn-relE toxin fromXenorhabdus nematophilapossessing its own antitoxin designated as Xn-relEAT has been identified. Expression and purification of recombinant proteins under native conditions with GST and Ni-NTA chromatography prove the existence of novel TA module. The expression of recombinant Xn-relE under tightly regulated ara promoter inE. coliTop 10 cells confirms its toxic nature in endogenous toxicity assay. The neutralization activity in endogenous toxicity assay by Xn-relEAT antitoxin confirms its antidote nature when studying the whole TA operon under ara regulated promoter. This study promotes newly discovered TA module to be regarded as important as other proteins of type II toxin-antitoxin system.
Gram-Negative Infections in Adult Intensive Care Units of Latin America and the Caribbean
Authors: Luna Carlos M. , Rodriguez-Noriega Eduardo , Bavestrello Luis , Guzmán-Blanco Manuel
Published: November 2014

This review summarizes recent epidemiology of Gram-negative infections in selected countries from Latin American and Caribbean adult intensive care units (ICUs). A systematic search of the biomedical literature (PubMed) was performed to identify articles published over the last decade. Where appropriate, data also were collected from the reference list of published articles, health departments of specific countries, and registries. Independent cohort data from all countries (Argentina, Brazil, Chile, Colombia, Cuba, Mexico, Trinidad and Tobago, and Venezuela) signified a high rate of ICU infections (prevalence: Argentina, 24%; Brazil, 57%). Gram-negative pathogens, predominantlyAcinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, andEscherichia coli, accounted for>50% of ICU infections, which were often complicated by the presence of multidrug-resistant strains and clonal outbreaks. Empirical use of antimicrobial agents was identified as a strong risk factor for resistance development and excessive mortality. Infection control strategies utilizing hygiene measures and antimicrobial stewardship programs reduced the rate of device-associated infections. To mitigate the poor health outcomes associated with infections by multidrug-resistant Gram-negative bacteria, urgent focus must be placed on infection control strategies and local surveillance programs.
A Challenging Twist in Pulmonary Renal Syndrome
Authors: Namas Rajaie , Rubin Bernard , Adwar Wamidh , Meysami Alireza
Published: November 2014

Case. We report a rare case of hydralazine-induced anti-neutrophil cytoplasmic antibody-associated vasculitis. A 75-year-old African American woman with history of high blood pressure on hydralazine for 3 years presented with acute onset of shortness of breath and hemoptysis. Lab workup revealed a severe normocytic anemia and a serum creatinine of 5.09 mg/dL (baseline 0.9). Bronchoscopy demonstrated active pulmonary hemorrhage. A urine sample revealed red cell casts and a renal biopsy demonstrated pauci-immune, focally necrotizing glomerulonephritis with small crescents consistent with possible anti-neutrophil cytoplasmic antibody-positive renal vasculitis. Serologies showed high-titer MPO-ANCA and high-titer anti-histone antibodies. She was treated with intravenous steroids and subsequently with immunosuppression after cessation of hydralazine. The patient was subsequently discharged from hospital after a rapid clinical improvement.Conclusion. Hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis is a rare adverse effect and can present as a severe vasculitic syndrome with multiple organ involvement. Features of this association include the presence of high titer of anti-myeloperoxidase anti-neutrophil cytoplasmic antibody with multiantigenicity, positive anti-histone antibodies, and the lack of immunoglobulin and complement deposition. Prompt cessation of hydralazine may be sufficient to reverse disease activity but immunosuppression may be needed.