57 research outputs found

    Magnetotransport in polycrystalline La2/3_{2/3}Sr1/3_{1/3}MnO3_{3} thin films of controlled granularity

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    Polycrystalline La2/3_{2/3}Sr1/3_{1/3}MnO3_{3} (LSMO) thin films were synthesized by pulsed laser ablation on single crystal (100) yttria-stabilized zirconia (YSZ) substrates to investigate the mechanism of magneto-transport in a granular manganite. Different degrees of granularity is achieved by using the deposition temperature (TD_{D}) of 700 and 800 0^{0}C. Although no significant change in magnetic order temperature (TC_C) and saturation magnetization is seen for these two types of films, the temperature and magnetic field dependence of their resistivity (ρ\rho(T, H)) is strikingly dissimilar. While the ρ\rho(T,H) of the 800 0^{0}C film is comparable to that of epitaxial samples, the lower growth temperature leads to a material which undergoes insulator-to-metal transition at a temperature (TP_{P} \approx 170 K) much lower than TC_C. At T \ll TP_P, the resistivity is characterized by a minimum followed by ln \emph{T} divergence at still lower temperatures. The high negative magnetoresistance (\approx 20%) and ln \emph{T} dependence below the minimum are explained on the basis of Kondo-type scattering from blocked Mn-spins in the intergranular material. Further, a striking feature of the TD_D = 700 0^{0}C film is its two orders of magnitude larger anisotropic magnetoresistance (AMR) as compared to the AMR of epitaxial films. We attribute it to unquenching of the orbital angular momentum of 3d electrons of Mn ions in the intergranular region where crystal field is poorly defined.Comment: 26 pages, 7 figure

    Existence and Construction of LCD codes over Finite Fields

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    We demonstrate the existence of Euclidean and Hermitian LCD codes over finite fields with various parameters. In addition, we provide a method for constructing multiple Hermitian LCD (self orthogonal, self dual) codes from a given Hermitian LCD (self orthogonal, self dual) code, as well as a method for constructing Euclidean (Hermitian) LCD codes with parameters [n+1,k+1][n+1, k+1] and [n,k+1][n,k+1] from a given Euclidean (Hermitian) LCD code with parameters [n,k][n,k] over finite fields. Finally, we provide some findings on σ\sigma-LCD codes over finite fields

    Combining ability analysis for yield and protein content in bread wheat (Triticum aestivum)

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    The experiment was conducted with 10 parents and their 45 F1s (half diallel) during crop seasons (2008/09 and 2009/10) under normal and heat-stress environment to find out combining ability effects. The analysis of variance showed highly significant differences for all the traits at genotypic level under both normal and heat-stress environment. The significant additive variance (D) and dominance variance (H1) indicated that, expression of these traits is controlled by both additive and non-additive gene action. Among the parents, there was asymmetrical distribution of positive and negative dominant genes and preponderance of over-dominance gene action for all the traits under both the environment. Estimates of narrow-sense heritability were higher for days to 50% flowering; days to maturity; plant height and spike length. Our results also indicated that only three parents (HD 2285 for grain filling duration and thousand grains weight; PBW 373 for the days to maturity and plant height and UP 2425 for number of tillers and grain yield) had favorable general combining ability (GCA) effects under normal sown environment. While under heat-stress environment, cultivar HD 2285 showed highest GCA effect for days to 50% flowering, grain filling duration and thousand grain weight; HD 2733 for plant height and protein content; and PBW 373 for number of tillers and grain yield. Five cross combinations showed contrasting favorable specific combining ability (SCA) effect for more than one trait under both normal and heat-stress environment. Attempting combinations involving parents with high GCA for desirable yield components could be useful. The traits showing more than 35 percent narrow-sense heritability could be rewarding for further improvement of grain yield and protein content in wheat (Triticum aestivum L.)

    Dopunska prehrana ribljim uljem poboljšala je funkciju jajnika, koncepciju i određene reprodukcijske pokazatelje kod kobila pasmine marvari

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    We investigated the effect of dietary fish oil supplementation on the development of the ovarian follicles, corpus luteum (CL), conceptus and certain reproductive events in Marwari mares, since it is reported to improve reproduction in cows. Accordingly, non-lactating mares (n = 20) were randomly assigned into two groups (10 per group) and fed either the control diet (CTR) or a diet enriched with fish oil (FOS) to supplement n-3 polyunsaturated fatty acids (PUFA) at the rate of 64 mg/kg body weight/day for 70 days or until 45 days post-ovulation in the mares that became pregnant. Estrus was detected using a teaser and insemination was performed using frozen thawed semen in the experimental mares. Development of the ovarian follicle, CL and conceptus were recorded using trans-rectal ultrasonography. Plasma concentrations of progesterone and estradiol were estimated by radioimmunoassay. In the FOS group, the diameter of the largest follicle from day 4 of estrus until ovulation, and the diameter of the CL on day 7 post-ovulation (D7PO) were greater (P<0.05). However, on day 15 post-ovulation (D15PO), the CL diameter increased significantly in the pregnant mares. Dietary fish oil significantly improved the development of the embryo as evidenced by an increase in the diameter of the embryonic vesicle on day 15 post-ovulation (D15PO), and the embryo proper on day 28 post ovulation (D28PO). Further, the mean plasma estradiol concentration was higher on the day of estrus onset (P<0.05) and day 4 of estrus (P<0.01) in the FOS group. Similarly, dietary fish oil significantly increased the plasma progesterone on D15PO in the pregnant mares (P<0.01). Although the duration of estrus was shorter by 19 hours (P<0.05), the length of the estrous cycle did not vary in the FOS group. A non-significant increase in the pregnancy rate was observed in the mares that received fish oil. It was concluded that dietary fish oil supplementation improved ovarian function and embryonic development in the Marwari mares.Na temelju prethodnih izvješća o poboljšanju reprodukcije krava, kod kobila pasmine marvari istražili smo učinak ribljeg ulja kao prehrambenog dodatka na razvoj folikula jajnika, žutog tijela, koncepcije i određenih reprodukcijskih pokazatelja. U skladu s ciljem, 20 kobila koje nisu bile u laktaciji je metodom slučajnog izbora podijeljeno u dvije skupine s po 10 kobila. Za razliku od kontrolne skupine, kobile u eksperimentalnoj skupini hranjene su obrokom obogaćenim ribljim uljem u obliku dodatka koji je sadržavao n-3 polinezasićene masne kiseline (PUFA), u dnevnoj količini od 64 mg na jedan kg tjelesne mase. Eksperiment je trajao 70 dana, odnosno za kobile koje su ostale gravidne do 45 dana nakon ovulacije. Estrus je praćen teaserom, a osjemenjivanje je provedeno zamrznutim sjemenom. Razvoj folikula jajnika i žutih tijela te gravidnosti praćeni su transrektalnim ultrazvukom. Koncentracija progesterona i estradiola u plazmi procijenjena je radioimunološkom metodom. U eksperimentalnoj skupini utvrđen je veći (P<0,05) promjer najvećeg folikula od 4. dana estrusa do ovulacije i veći promjer žutog tijela 7. dan nakon ovulacije. No, 15. dan nakon ovulacije promjer žutih tijela bio je signifikantno povećan kod gravidnih kobila. Obrok obogaćen ribljim uljem signifikantno je poboljšao razvoj embrija, što se očitovalo povećanjem promjera embrionalne vezikule 15. dan nakon ovulacije i povećanjem embrija 28. dan nakon ovulacije. Nadalje, u eksperimentalnoj skupini kobila srednja koncentracija estradiola u plazmi bila je veća na dan početka estrusa (P<0,05) i 4. dan estrusa (P<0,01). Slično tome, obrok obogaćen ribljim uljem kod gravidnih je kobila signifikantno (P<0,01) povećao progesteron u plazmi 15. dan nakon ovulacije. U kobila eksperimentalne skupine je, uz varijacije estrusnog ciklusa, utvrđeno i za 19 sati kraće trajanje estrusa (P<0,05). Povećana stopa gravidnosti kod kobila dohranjivanih ribljim uljem nije bila signifikantna. Zaključeno je da je hranidba s dodatkom ribljeg ulja kod kobila pasmine marvari poboljšala funkciju jajnika i razvoj embrija

    Germplasm characterization, association and clustering for salinity and waterlogging tolerance in bread wheat (Triticum aestivum)

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    A study was conducted for characterizing germplasm, estimating interrelationship of traits and clustering of wheat genotypes in five environments covering salinity, waterlogging and neutral soils using, 100 elite but diverse genotypes with eight checks of bread wheat (Triticum aestivum L.). These genotypes were planted under five distinct environments during rabi 2009-10 under augmented design in four blocks wherein each check was repeated twice. The genetic variance, correlation coefficients and cluster analysis were carried out for assessment of lines through seven metric traits, namely, plant stand, plant height, days to heading, days to maturity, tillers/meter, 1000-grain weight and grain yield. Analysis of variance revealed wide variability for most of the traits under study. The phenotypic coefficient of variation (PCV) was high for tillers/meter and grain yield, while high heritability coupled with high genetic advance were found for tillers/meter, 1000-grain weight and grain yield under all five environments. At phenotypic level, positive and significant correlation coefficients revealed that under all the normal and stressed environments used here, grain yield is directly influenced by plant stand, tillers/meter and thousand grain weights. Significant and positive correlations were estimated between tillers/meter (r = 0.31 to 0.66), and 1000 grain weight (r = 0.24 to 0.61) with grain yield under all five environments. Under waterlogged conditions there were significant negative correlations of plant height to grain yield (r = –0.38 to –0.39) across two sites. These results, thereby suggests that yield improvement in bread wheat could be possible by emphasizing these traits through selection in these diverse environments. On the basis of D2 values of pooled data, 108 genotypes were grouped into four clusters. In all, only 26 lines were found common in cluster III under two waterlogging environments (Faizabad and Karnal), while only 15 lines were common in cluster I under non waterlogging (Faizabad, CSSRI and DWR) conditions. These results indicate different constraints exist in waterlogged and non-waterlogged condition at these sites. Genetic diversity available for these traits may be utilized for yield improvement in bread wheat under different soil conditions through planned hybridization and selection in target environments

    Prognostic Value of Normal Stress Echocardiography in Obese Patients

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    Background. Chest pain is a common problem in obese patients. Because of the body habitus, the results of noninvasive evaluation for CAD may be limited in this group. Methods. We reviewed the records of 1446 consecutive patients who had undergone clinically indicated stress echocardiography (SE). We compared major adverse cardiac events (MACE; myocardial infarction, cardiac intervention, cardiac death, subsequent hospitalization for cardiac events, and emergency department visits) at 1 year in normal weight, overweight, and obese subjects with normal SE. Results. Excluding patients with an abnormal and indeterminate SE and those who were lost to follow-up, a retrospective analysis of 704 patients was performed. There were 366 obese patients (BMI ≥ 30), 196 overweight patients (BMI 25-29.9), and 142 patients with normal BMI (18.5-24.9). There was no MACE in the groups at 1-year follow-up after a normal SE. Conclusions. In obese patients including those with multiple risk factors and symptoms concerning for cardiac ischemia, stress echocardiography is an effective and reliable noninvasive tool for identifying those with a low 1-year risk of cardiac events

    Harnessing genetic potential of wheat germplasm banks through impact-oriented-prebreeding for future food and nutritional security

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    The value of exotic wheat genetic resources for accelerating grain yield gains is largely unproven and unrealized. We used next-generation sequencing, together with multi-environment phenotyping, to study the contribution of exotic genomes to 984 three-way-cross-derived (exotic/elite1//elite2) pre-breeding lines (PBLs). Genomic characterization of these lines with haplotype map-based and SNP marker approaches revealed exotic specific imprints of 16.1 to 25.1%, which compares to theoretical expectation of 25%. A rare and favorable haplotype (GT) with 0.4% frequency in gene bank identified on chromosome 6D minimized grain yield (GY) loss under heat stress without GY penalty under irrigated conditions. More specifically, the ‘T’ allele of the haplotype GT originated in Aegilops tauschii and was absent in all elite lines used in study. In silico analysis of the SNP showed hits with a candidate gene coding for isoflavone reductase IRL-like protein in Ae. tauschii. Rare haplotypes were also identified on chromosomes 1A, 6A and 2B effective against abiotic/biotic stresses. Results demonstrate positive contributions of exotic germplasm to PBLs derived from crosses of exotics with CIMMYT’s best elite lines. This is a major impact-oriented pre-breeding effort at CIMMYT, resulting in large-scale development of PBLs for deployment in breeding programs addressing food security under climate change scenarios

    Effect of surgical experience and spine subspecialty on the reliability of the {AO} Spine Upper Cervical Injury Classification System

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    OBJECTIVE The objective of this paper was to determine the interobserver reliability and intraobserver reproducibility of the AO Spine Upper Cervical Injury Classification System based on surgeon experience (&lt; 5 years, 5–10 years, 10–20 years, and &gt; 20 years) and surgical subspecialty (orthopedic spine surgery, neurosurgery, and "other" surgery). METHODS A total of 11,601 assessments of upper cervical spine injuries were evaluated based on the AO Spine Upper Cervical Injury Classification System. Reliability and reproducibility scores were obtained twice, with a 3-week time interval. Descriptive statistics were utilized to examine the percentage of accurately classified injuries, and Pearson’s chi-square or Fisher’s exact test was used to screen for potentially relevant differences between study participants. Kappa coefficients (κ) determined the interobserver reliability and intraobserver reproducibility. RESULTS The intraobserver reproducibility was substantial for surgeon experience level (&lt; 5 years: 0.74 vs 5–10 years: 0.69 vs 10–20 years: 0.69 vs &gt; 20 years: 0.70) and surgical subspecialty (orthopedic spine: 0.71 vs neurosurgery: 0.69 vs other: 0.68). Furthermore, the interobserver reliability was substantial for all surgical experience groups on assessment 1 (&lt; 5 years: 0.67 vs 5–10 years: 0.62 vs 10–20 years: 0.61 vs &gt; 20 years: 0.62), and only surgeons with &gt; 20 years of experience did not have substantial reliability on assessment 2 (&lt; 5 years: 0.62 vs 5–10 years: 0.61 vs 10–20 years: 0.61 vs &gt; 20 years: 0.59). Orthopedic spine surgeons and neurosurgeons had substantial intraobserver reproducibility on both assessment 1 (0.64 vs 0.63) and assessment 2 (0.62 vs 0.63), while other surgeons had moderate reliability on assessment 1 (0.43) and fair reliability on assessment 2 (0.36). CONCLUSIONS The international reliability and reproducibility scores for the AO Spine Upper Cervical Injury Classification System demonstrated substantial intraobserver reproducibility and interobserver reliability regardless of surgical experience and spine subspecialty. These results support the global application of this classification system

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
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