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NILAPARVATA lugens, RICE, INSECT pests, SINGLE nucleotide polymorphisms, FOOD crops, and IDENTIFICATION

Rice is the most important staple food crop, and it feeds more than half of the world population. Brown planthopper (BPH) is a major insect pest of rice that causes 20–80% yield loss through direct and indirect damage. The identification and use of BPH resistance genes can efficiently manage BPH. A molecular marker-based genetic analysis of BPH resistance was carried out using 101 BC1F5 mapping population derived from a cross between a BPH-resistant indica variety Khazar and an elite BPH-susceptible line Huang–Huan–Zhan. The genetic analysis indicated the existence of Mendelian segregation for BPH resistance. A total of 702 high-quality polymorphic single nucleotide polymorphism (SNP) markers, genotypic data, and precisely estimated BPH scores were used for molecular mapping, which resulted in the identification of the BPH38(t) locus on the long arm of chromosome 1 between SNP markers 693,369 and id 10,112,165 of 496.2 kb in size with LOD of 20.53 and phenotypic variation explained of 35.91%. A total of 71 candidate genes were predicted in the detected locus. Among these candidate genes, LOC_Os01g37260 was found to belong to the FBXL class of F-box protein possessing the LRR domain, which is reported to be involved in biotic stress resistance. Furthermore, background analysis and phenotypic selection resulted in the identification of introgression lines (ILs) possessing at least 90% recurrent parent genome recovery and showing superior performance for several agro-morphological traits. The BPH resistance locus and ILs identified in the present study will be useful in marker-assisted BPH resistance breeding programs. [ABSTRACT FROM AUTHOR]

HIGGS bosons, SCALAR field theory, SUPERSYMMETRY, STANDARD model (Nuclear physics), DARK matter, and MATHEMATICAL models

The goal of this report is to summarize the current situation and discuss possible search strategies for charged scalars, in non-supersymmetric extensions of the Standard Model at the LHC. Such scalars appear in Multi-Higgs-Doublet models, in particular in the popular Two-Higgs-Doublet model, allowing for charged and additional neutral Higgs bosons. These models have the attractive property that electroweak precision observables are automatically in agreement with the Standard Model at the tree level. For the most popular version of this framework, Model II, a discovery of a charged Higgs boson remains challenging, since the parameter space is becoming very constrained, and the QCD background is very high. We also briefly comment on models with dark matter which constrain the corresponding charged scalars that occur in these models. The stakes of a possible discovery of an extended scalar sector are very high, and these searches should be pursued in all conceivable channels, at the LHC and at future colliders. [ABSTRACT FROM AUTHOR]

Striated craniofacial and limb muscles differ in their embryological origin, regulatory program during myogenesis, and innervation. In an attempt to explore the effects of these differences on the striated muscle phenotype in humans, the expression of myosin and myosin-associated thick filament proteins were studied at the single fiber level both in the human jaw-closing masseter muscle and in two limb muscles (biceps brachii and quadriceps femoris muscles). In the masseter, unique combinations of myosin heavy chain (MyHC) and myosin binding protein C (MyBP-C) isoforms were observed at the single fiber level. Compared to the limb muscles, the MyHC isoform expression was more complex in the masseter while the opposite was observed for MyBP-C. In limb muscles, a coordinated expression of three MyHC and three MyBP-C isoforms were observed, i.e., single fibers contained one or two MyHC isoforms, and up to three MyBP-C isoforms. Also, the relative content of the different MyBP-C isoforms correlated with the MyHC isoform expression. In the masseter, on the other hand, up to five different MyHC isoforms could be observed in the same fiber, but only one MyBP-C isoform was identified irrespective MyHC isoform expression. This MyBP-C isoform had a migration rate similar to the slow MyBP-C isoform in limb muscle fibers. In conclusion, a unique myofibrillar protein isoform expression was observed in the human masseter muscle fibers, suggesting significant differences in structural and functional properties between muscle fibers from human masseter and limb muscles. [ABSTRACT FROM AUTHOR]

INTERTIDAL ecology, SEDIMENTATION & deposition, POLYMERIC composites, DIATOMS, and ALGAE

The sediment-stabilizing effect of benthic diatoms was investigated in a laboratory setting. Axenic cultures of the benthic diatoms Nitzschia cf. brevissima and Cylindrotheca closterium were inoculated in Petri dishes containing sand and incubated under axenic conditions. By ensuring aseptic routines throughout the experiments, interference from other organisms occurring with diatoms in natural photothrophic biofilms was avoided. This allowed the examination of the role of benthic diatoms in sediment stabilization. Increases in the critical erosion shear stress of the sediment were observed in the presence of both diatom taxa relative to sterile sediment. However, N. cf. brevissima was more effective than C. closterium. Values of critical shear stress in the experimental system were in the same range as those observed in natural biofilms, which indicates that diatoms are important agents for biogenic stabilization. Extracellular carbohydrate contents in the microcosms were similar for both diatom species. However, in the presence of N cf. brevissima, extracellular carbohydrate correlated significantly to critical shear stress, explaining up to 80% of the variation, whereas this was not the case for C. closterium. Therefore, it was concluded that the quantity of extracellular polymeric substances (EPS) alone did not explain the biogenic stabilization. Observed adsorption of EPS to sediment particles depended on the relative amount of uronic acids in the exopolymers. Using fluorescently labeled lectins, confocal laser scanning microscopy showed that EPS secretion by N. cf. brevissima resulted in ordered three-dimensional matrix structures. It is suggested that the structuring of EPS plays an prominent role in the process of biostabilization, and that diatoms such as N. cf. brevissima are actively involved in producing the structure of EPS, whereas others such as C. closterium do not do so to the same extent. [ABSTRACT FROM AUTHOR]

NITROGEN fixation and OCEAN

Explores the ecological aspects of dinitrogen fixation in the world's oceans. Diversity of dinitrogen-fixing microorganisms; Major controls on rates of oceanic dinitrogen fixation; Significance of dinitrogen fixation for the global carbon cycle; Role of human activities in the alteration of oceanic dinitrogen fixation.

The aim of this study was to investigate whether different mammographic categories of interval cancer classified according to findings at the latest screening are associated with different distributions of prognostic factors or with different survival rates. The series consisted of all patients with invasive interval cancer detected from May 1978 to August 1995 (n = 544). The tumours were evaluated with regard to age, radiological category, interval between the latest screen and diagnosis and tumour characteristics at the time of diagnosis. We investigated possible relationships between the survival rate of patients with interval cancer and the interval between the latest screen and diagnosis, tumour characteristics and radiological category of the interval tumours. The study focused on comparison of patients with true interval and missed interval cancer. Women with mammographically occult tumours were younger than those in the other radiological categories. Comparisons of true interval cancers with overlooked or misinterpreted tumours showed equal distributions of age, tumour size, TNM stage and lymph node status. The overlooked or misinterpreted tumours showed significantly higher proportions of grade-I tumours (22 vs 11 %), tumours with low S-phase fraction (SPF; 44 vs 24 %) and oestrogen receptor (ER) positive tumours (72 vs 57 %). However, analyses of survival rates disclosed no clear differences between the two radiological categories. Radiological category and interval between the latest screen and diagnosis were not genuine predictors of the prognosis in patients with invasive interval breast cancer. No certain prognostic difference existed between true interval cancers and overlooked or misinterpreted interval breast cancers, despite higher proportions of grade-I tumours, ER positive tumours and tumours with low SPF in the latter group. [ABSTRACT FROM AUTHOR]

In the sintering shop at OAO Ural'skaya Stal', industrial trials are conducted with a view to improving the pelletization by wetting the sintering batch with water-soluble organic surfactants. The use of surfactants improves the granulometric composition of the batch, its gas permeability, and hence the sintering efficiency. The use of surfactant is most effective with optimal wetting of the batch (7-8%), with consumption of the experimental binder at a rate of 1.2-1.6 L/h. (The surfactant concentration in aqueous solution is 0.3⎯0.4 mL/L.) [ABSTRACT FROM AUTHOR]

Detailed morphological redescriptions of cockroaches of the subfamily Epilamprinae Brunner von Wattenwyl, 1865 from the New World based on the collection of the Zoological Institute of the Russian Academy of Sciences are given. Poeciloderrhis verticalis (Burmeister, 1838), the type species of the genus Poeciloderrhis Stål, 1874; Phoraspis picta (Drury, 1782), the type species of the genus Phoraspis Serville, 1831; Epilampra mexicana Saussure, 1862 and E. sodalis Walker, 1868, the members of the ' mexicana' and ' sodalis' species-groups, respectively, are redescribed. Parapoeciloderrhis dilatatus Anisyutkin, gen. et sp. n. is described from Ecuador. The paper pays special attention to the structures of the male and female genitalia. The hypothetical relationships between the taxa studied are briefly considered. The possible synapomorphies of the group [ Poeciloderrhis, Epilampra, and Phoraspis] are considered. The genus Epilampra is possibly artificial and needs division into several genera. [ABSTRACT FROM AUTHOR]

SALIVARY glands, DIGESTIVE enzymes, HEMIPTERA, PLANT parasites, and COWPEA

The salivary glands of the cowpea pod-sucking bugs Anoplocnemis curvipes (Fabricius), Clavigralla tomentosicollis Stål, Clavigralla shadabi Dolling, Riptortus dentipes (Fabricius) and Mirperus jaculus (Thunberg) are described and illustrated. Extracts of the glands were assayed for the presence of proteinases, α-amylase, β-amylase and amyloglucosidase. The salivary glands consist of four-lobed principal glands and a tubular accessory gland, and they differ in shape and size among the different species except for the median lobe, which is more or less spherical. The sickle-shaped nature of the posterior lobe reported before for Riptortus linearis (Linnaeus) was also observed in R. dentipes, suggestive of a probable generic characteristic. Anoplocnemis curvipes has the biggest salivary gland, and it is followed by R. dentipes, M. jaculus, C. tomentosicollis and C. shadabi in descending order. Assays of the gland extracts revealed that the four digestive enzymes tested are present in the five coreoid species. Proteinases were preponderant (1.4-94.9 µg/ml), while amylases were detected in traces [(0.5-11.0) x 10-3 µg/ml]. Proteinases may be largely responsible for the feeding damage caused by the coreoid species and their concentration in the glands of the different species correlates well with their known capacity to inflict pod damage and yield reduction in cowpea. Fourth instar nymphs of the different species also had higher concentrations of the digestive enzymes compared with their respective adults; and this correlates with the known ability of the nymphs to cause greater pod damage and yield reduction than adults. [ABSTRACT FROM AUTHOR]

This paper describes blistering of rhenium following 21 keV He-ion irradiation at temperatures between 300 K and 1200 K. Blistering starts at 300 K at a dose of 3×10 ions/cm. The most probable blister diameter varies from 4400 Å at 300 K to 10100 Å at 1200 K. The blister depth τ, the blister diameter φ and the blister height h show a distribution. From the observations one could derive the following relationships: h = 0.35φ; τ=3.43φ. The erosion yield E due to blistering is function of dose E =0.51 atoms/ion at 3×10 ions/cm, E =0.56 atoms/ion at 6×10 ions/cm and E =0.14 atoms/ion at 3×10 ions/cm. The sputtering yield S (21 keV) is estimated to be ∼0.1 atom/ion. The corresponding surface regression is 44Å at 3×10 ions/cm and 1323 Å at 9×10 ions/cm. Surface regression has therefore little influence on the observations at low doses. [ABSTRACT FROM AUTHOR]

NILAPARVATA lugens, PHOSPHORIBOSYLTRANSFERASES, HISTIDINE, PROTEIN synthesis, and MESSENGER RNA

Histidine is an essential amino acid assumed to be synthesized by an obligatory yeast-like symbiont ( Entomomyces delphacidicola str. NLU) in Nilaparvata lugens, an important rice pest. The adenosine-triphosphate phosphoribosyltransferase (ATP-PRTase) facilities the committed first step of the histidine biosynthesis pathway. In the current study, a putative ATP- PRTase was cloned and verified to be of E. delphacidicola origin ( EdePRTase). The expression of the gene was spatial and temporal universal with a profile that matched the distribution of the fungal symbiont. RNA interference aided the knockdown of the EdePRTase-suppressed EdePRTase expression by 32-48 %. Hemolymph histidine level was also reduced followed by significant reduction of adult body weight. However, other performance characters including nymph development, survival, and adult sex ratio were not adversely affected by the knockdown. Furthermore, forced histidine exposure (through injection or feeding) significantly inhibited the EdePRTase mRNA levels at higher concentrations, but significantly increased EdePRTase expression levels at lower concentrations (feeding only). The significance of these findings support that the EdePRTase is from symbiont E. delphacidicola, and its involvement in histidine biosynthesis of N. lugens was discussed. The results provide a better understanding of EdePRTase and the encoded functional ATP-PRTase enzyme regulation in N. lugens and insects in general. [ABSTRACT FROM AUTHOR]

CYANOBACTERIA, NITROGEN fixation, and PHOTOSYNTHESIS

NITROGEN fixation, CYANOBACTERIA, MARINE biology, and MICROBIOLOGY

MYELOFIBROSIS, JANUS kinases, HEMATOPOIETIC stem cell transplantation, MYELOSUPPRESSION, CLINICAL trials, THERAPEUTICS, DRUG therapy, COMPARATIVE studies, HETEROCYCLIC compounds, RESEARCH methodology, MEDICAL cooperation, BIOLOGICAL mutation, RESEARCH, RESEARCH funding, EVALUATION research, TREATMENT effectiveness, KAPLAN-Meier estimator, PROTEIN kinase inhibitors, and DIAGNOSIS

Myelofibrosis (MF) is a chronic yet progressive myeloid neoplasm in which only a minority of patients undergo curative therapy, hematopoietic stem cell transplantation. Ruxolitinib, a JAK1/2 inhibitor, is the lone therapy approved for MF, offering a clear symptom and spleen benefit at the expense of treatment-related cytopenias. Pacritinib (PAC), a multi-kinase inhibitor with specificity for JAK2, FLT3, and IRAK1 but sparing JAK1, has demonstrated clinical activity in MF with minimal myelosuppression. Due to an FDA-mandated full clinical hold, the randomized phase 3 PERSIST trials were abruptly stopped and PAC was immediately discontinued for all patients. Thirty-three patients benefitting from PAC on clinical trial prior to the hold were allowed to resume therapy on an individual, compassionate-use basis. This study reports the detailed outcomes of 19 of these PAC retreatment patients with a median follow-up of 8 months. Despite a median platelet count of 49 × 109/L at restart of PAC, no significant change in hematologic profile was observed. Grade 3/4 adverse events of epistaxis (n = 1), asymptomatic QT prolongation (n = 1), and bradycardia (n = 1) occurred in three patients within the first 3 months of retreatment. One death due to catheter-associated sepsis occurred. The median time to discontinuation of PAC therapy on compassionate use for all 33 patients was 12.2 (95% CI 8.3-NR) months. PAC retreatment was associated with modest improvement in splenomegaly without progressive myelosuppression and supports the continued development of this agent for the treatment of MF second line to ruxolitinib or in the setting of treatment-limiting thrombocytopenia. [ABSTRACT FROM AUTHOR]

ELECTRICAL steel, ELECTRICAL engineering materials, SILICON steel, STEEL, IRON, and STEEL alloys

The results of investigation of the relation between the grain size in the intermediate stages of manufacturing electrical steel and various physical characteristics are given. The investigations are carried out for the purpose of clarifying the possibility of using these characteristics for arranging nondestructive testing of the grain size in the process of steel manufacturing. The paper contains the results of tests performed with the use of the methods of measuring the leakage magnetic fields on the grain boundaries by means of yttrium iron garnet films employed for visualization of the magnetic fields, the Barkhausen effect, the ultrasonic and eddy-current methods, the electromagnetic-acoustic conversion (EMAC) method, and the use of the relation between the grain size and the value of the coercive force. [ABSTRACT FROM AUTHOR]