987 resultados para 169-1034


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Mr=328.32, triclinic, P1, a=5.801 (1), b=7.977(1), c=9.110(2)A, ~t=102.33 (1), fl= 97.92 (1), y= 109.82 (1) °, v= 377.2 (1) A 3 at 293 K, Z=I, D x=1.45, D m=1.45 g cm -3, 2(MoKs)= 0.7107 A, ~ = 0.74 cm -1, F(000) = 174.0. R = 0.046 for 990 unique observed [F o > 4O(Fo)] reflections. The crystal structure is stabilized by extensive hydrogen bonding involving all N and O atoms.

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The methods for estimating methane emissions from cattle as used in the Australian national inventory are based on older data that have now been superseded by a large amount of more recent data. Recent data suggested that the current inventory emissions estimates can be improved. To address this issue, a total of 1034 individual animal records of daily methane production (MP) was used to reassess the relationship between MP and each of dry matter intake (DMI) and gross energy intake (GEI). Data were restricted to trials conducted in the past 10 years using open-circuit respiration chambers, with cattle fed forage-based diets (forage >70%). Results from diets considered to inhibit methanogenesis were omitted from the dataset. Records were obtained from dairy cattle fed temperate forages (220 records), beef cattle fed temperate forages (680 records) and beef cattle fed tropical forages (133 records). Relationships were very similar for all three production categories and single relationships for MP on a DMI or GEI basis were proposed for national inventory purposes. These relationships were MP (g/day) = 20.7 (±0.28) × DMI (kg/day) (R2 = 0.92, P < 0.001) and MP (MJ/day) = 0.063 (±0.008) × GEI (MJ/day) (R2 = 0.93, P < 0.001). If the revised MP (g/day) approach is used to calculate Australia’s national inventory, it will reduce estimates of emissions of forage-fed cattle by 24%. Assuming a global warming potential of 25 for methane, this represents a 12.6 Mt CO2-e reduction in calculated annual emissions from Australian cattle.

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Reaction of Bi2O3 with MgO, NiO, Co3O4 and Al2O3 gives rise to the corresponding ternary bismuth oxides, Bi18Mg8O36, Bi18Ni8O36, Bi20Co6O39 and Bi24Al2O39. These oxides have the general formula Bi26�xMxO40�y and exhibit BCC structures related to α - Bi2O3. In the first three solids, the metal ions, M, replace bismuth randomly at the octahedral 24r sites (space group 123); in the last case, aluminium ions occupy the tetrahedral 2a sites, the phase being isostructural with Bi24Ge2O40. Starting from Bi2O3 and NiO, orthorhombic Bi2Ni2O5 has also been obtained.

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The gall fly Cecidochares connexa (Diptera: Tephritidae) is a potential biological control agent for Chromolaena odorata in Australia. Its host specificity was determined against 18 species in the tribe Eupatorieae (Family Asteraceae) in which C. odorata belongs, in quarantine in Brisbane, Australia. Oviposition occurred and flies developed on only C. odorata and Praxelis clematidea, both of which are in the subtribe Praxelinae. P. clematidea is considered a weed outside tropical America. In both multiple-species-minus-C. odorata choice tests and single-species no-choice tests, the mean number of galls/plant was significantly greater on C. odorata (48 and 41, respectively) than on P. clematidea (2 and 9, respectively). There were also significantly more adults emerging from C. odorata (mean 129 and 169, respectively) in the two types of tests than from P. clematidea (1 and 8, respectively). Paired choice, multiple generation (continuation) and time dependent tests further clarified the extent that C. connexa could develop on P. clematidea. In these tests, the mean number of galls formed and the mean number of emerging adults were consistently less for P. clematidea than C. odorata and populations of C. connexa could not be maintained on P. clematidea. Galls were not seen on any other plant species tested. This study supports the results of host specificity testing conducted in seven other countries and confirms that C. connexa poses little risk to other plant species in Australia. C. connexa has been released in 10 countries and an application seeking approval to release in Australia has been submitted to the Australian Government.

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A rate equation is developed for the liquid phase hydrogenation of aniline over cylindrical catalyst pellets of 30% nickel deposited on clay in a trickle bed reactor. The equation takes into account external and internal diffusional limitations, and describes the experimental data adequately. The hydrogenation reaction is first order with respect to hydrogen and zero order with respect to aniline. Effectiveness factors are in the range 0.003-0.03. Apparent activation energy of the reaction is 12.7 kcal/mol and true activation energy is 39.6 kcal/mol.

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A generalised theory for the natural vibration of non-uniform thin-walled beams of arbitrary cross-sectional geometry is proposed. The governing equations are obtained as four partial, linear integro-differential equations. The corresponding boundary conditions are also obtained in an integro-differential form. The formulation takes into account the effect of longitudinal inertia and shear flexibility. A method of solution is presented. Some numerical illustrations and an exact solution are included.

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Depending on their developmental stage in the life cycle, malaria parasites develop within or outside host cells, and in extremely diverse contexts such as the vertebrate liver and blood circulation, or the insect midgut and hemocoel. Cellular and molecular mechanisms enabling the parasite to sense and respond to the intra- and the extra-cellular environments are therefore key elements for the proliferation and transmission of Plasmodium, and therefore are, from a public health perspective, strategic targets in the fight against this deadly disease. The MALSIG consortium, which was initiated in February 2009, was designed with the primary objective to integrate research ongoing in Europe and India on i) the properties of Plasmodium signalling molecules, and ii) developmental processes occurring at various points of the parasite life cycle. On one hand, functional studies of individual genes and their products in Plasmodium falciparum (and in the technically more manageable rodent model Plasmodium berghei) are providing information on parasite protein kinases and phosphatases, and of the molecules governing cyclic nucleotide metabolism and calcium signalling. On the other hand, cellular and molecular studies are elucidating key steps of parasite development such as merozoite invasion and egress in blood and liver parasite stages, control of DNA replication in asexual and sexual development, membrane dynamics and trafficking, production of gametocytes in the vertebrate host and further parasite development in the mosquito. This article, which synthetically reviews such signalling molecules and cellular processes, aims to provide a glimpse of the global frame in which the activities of the MALSIG consortium will develop over the next three years.

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A single administration of 2-allyl-2-isopropylacetamide, a porphyrinogenic drug, enhanced the 32P-labelling of nucleoplasmic as well as cytoplasmic poly(A)-containing RNA in rat liver. The synthesis of total microsomal RNA is only marginally increased under these conditions. The drug enhances the labelling of a variety of cytoplasmic poly(A)-containing RNA species, and this effect is counteracted by the simultaneous administration of haemin. 2-Allyl-2-isopropylacetamide also enhanced the release of RNA from the nucleus to the cytoplasm.

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My System of Career Influences (MSCI) is a qualitative guided reflection process for adolescents and for adults that is based on the Systems Theory Framework (STF; McMahon & Patton, 1995; Patton & McMahon, 1999, 2006, 2014) of career development. Reflective of the trend towards more holistic theories and models of career counselling, the MSCI enables users to identify, prioritise and story their career influences, thus enabling them to contextualise career decisions and career transitions.

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Context: Pheochromocytomas and paragangliomas (PPGLs) are heritable neoplasms that can be classified into gene-expression subtypes corresponding to their underlying specific genetic drivers. Objective: This study aimed to develop a diagnostic and research tool (Pheo-type) capable of classifying PPGL tumors into gene-expression subtypes that could be used to guide and interpret genetic testing, determine surveillance programs, and aid in elucidation of PPGL biology. Design: A compendium of published microarray data representing 205 PPGL tumors was used for the selection of subtype-specific genes that were then translated to the Nanostring gene-expression platform. A support vector machine was trained on the microarray dataset and then tested on an independent Nanostring dataset representing 38 familial and sporadic cases of PPGL of known genotype (RET, NF1, TMEM127, MAX, HRAS, VHL, and SDHx). Different classifier models involving between three and six subtypes were compared for their discrimination potential. Results: A gene set of 46 genes and six endogenous controls was selected representing six known PPGL subtypes; RTK1–3 (RET, NF1, TMEM127, and HRAS), MAX-like, VHL, and SDHx. Of 38 test cases, 34 (90%) were correctly predicted to six subtypes based on the known genotype to gene-expression subtype association. Removal of the RTK2 subtype from training, characterized by an admixture of tumor and normal adrenal cortex, improved the classification accuracy (35/38). Consolidation of RTK and pseudohypoxic PPGL subtypes to four- and then three-class architectures improved the classification accuracy for clinical application. Conclusions: The Pheo-type gene-expression assay is a reliable method for predicting PPGL genotype using routine diagnostic tumor samples.

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The silver-headed antechinus (Antechinus argentus) is one of Australia’s most recently described mammals, and the single known population at Kroombit Tops in south-east Queensland is threatened. Nothing is known of the species’ ecology, so during 2014 we collected faecal pellets each month (March–September) from a population at the type locality to gather baseline data on diet composition. A total of 38 faecal pellets were collected from 12 individuals (eight females, four males) and microscopic analysis of pellets identified seven invertebrate orders, with 70% combined mean composition of beetles (Coleoptera: 38%) and cockroaches (Blattodea: 32%). Other orders that featured as prey were ants, crickets/grasshoppers, butterflies/moths, spiders, and true bugs. Given that faecal pellets could only be collected from a single habitat type (Eucalyptus montivaga high-altitude open forest) and location, this is best described as a generalist insectivorous diet that is characteristic of other previously studied congeners.

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A mathematical model is developed to simulate oxygen consumption, heat generation and cell growth in solid state fermentation (SSF). The fungal growth on the solid substrate particles results in the increase of the cell film thickness around the particles. The model incorporates this increase in the biofilm size which leads to decrease in the porosity of the substrate bed and diffusivity of oxygen in the bed. The model also takes into account the effect of steric hindrance limitations in SSF. The growth of cells around single particle and resulting expansion of biofilm around the particle is analyzed for simplified zero and first order oxygen consumption kinetics. Under conditions of zero order kinetics, the model predicts upper limit on cell density. The model simulations for packed bed of solid particles in tray bioreactor show distinct limitations on growth due to simultaneous heat and mass transport phenomena accompanying solid state fermentation process. The extent of limitation due to heat and/or mass transport phenomena is analyzed during different stages of fermentation. It is expected that the model will lead to better understanding of the transport processes in SSF, and therefore, will assist in optimal design of bioreactors for SSF.

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Esophageal atresia (EA), a common congenital anomaly comprising interrupted esophagus with or without a tracheoesophageal fistula (TEF), affects one in 2840 newborns. Over half have associated anomalies. After EA repair in infancy, gastroesophageal reflux (GER) and esophageal dysmotility and respiratory problems are common. As there exist no previous population-based long-term follow-up-studies on EA, its long-term sequelae are unclear. The aims of this study were to assess the cancer incidence (I), esophageal morbidity and function (II), respiratory morbidity (III), and the spinal defects (IV) in adults with repaired EA. All patients treated for EA at the Hospital for Children and Adolescents, University of Helsinki, from 1947 to 1985 were identified, and those alive with their native esophagus were contacted, and the first hundred who replied made up the study group. The patients were interviewed, they filled in symptom questionnaires, and they underwent esophageal endoscopy and manometry, pulmonary function tests, and a full orthopedic evaluation was performed with radiographs of the spine. The questionnaire was also sent by mail to adults with repaired EA not attending the clinical study, and to 287 general population-derived controls matched for age, gender, and municipality of residence. Incidence of cancer among the study population was evaluated from the population-based countrywide cancer registry. 169 (72%) adults with repaired EA replied; 101 (42%) (58 male) participated in the clinical studies at a median age of 36 years (range, 22-56). Symptomatic GER occurred in 34% and dysphagia in 85% of the patients and in 8% and 2% of the controls (P<0.001 for both). The main endoscopic findings included hiatal hernia (28%), Barrett´s esophagus (11%), esophagitis (8%), and stenotic anastomosis (8%). Histology revealed esophagitis in 25 individuals, and epithelial metaplasia in another 21. At immunohistochemistry, CDX2-positive columnar epithelial metaplasia was present in all 21 individuals, and 6 of these also demonstrated goblet cells and MUC2 positivity. In all histological groups, GER and dysphagia were equally common (P=ns). Esophageal manometry demonstrated non-propagating peristalsis in most of the patients, and low ineffective pressure of the distal esophageal body in all. The changes were significantly worse in those with epithelial metaplasia (P≤0.022). Anastomotic complications (OR 8.6-24, 95%CI 1.7-260, P=0.011-0.008), age (OR 20, 95%CI 1.3-310, P=0.034), low distal esophageal body pressure (OR 2.6, 95%CI 0.7-10, P=0.002), and defective esophageal peristalsis (OR 2.2, 95%CI 0.4-11, P=0.014) all predicted development of epithelial metaplasia. Despite the high incidence of esophageal metaplasia, none of the EA patients had suffered esophageal cancer, according to the Finnish Cancer Registry. Although three had had cancer (SIR, 1.0; 95% CI, 0.20-2.8). The overall cancer incidence among adults with repaired EA did not differ from that of the general Finnish population. Current respiratory symptoms occurred in 11% of the patients and 2% of the controls (P<0.001). Of the patients, 16%, and 6% of the controls had doctor-diagnosed asthma (P<0.001). A total of 56% and 70% of the patients and 20% and 50% of the controls had a history of pneumonia and of bronchitis (P<0.001 for both). Respiratory-related impaired quality of life was observable in 11% of the patients in contrast to 6% of the controls (P<0.001). PFT revealed obstruction in 21 of the patients, restriction in 21, and both in 36. A total of 41 had bronchial hyper-responsiveness (BHR) in HCT, and 15 others had an asthma-like response. Thoracotomy-induced rib fusion (OR 3.4, 95%CI 1.3-8.7, P=0.01) and GER-associated epithelial metaplasia in adulthood (OR 3.0, 95%CI 1.0-8.9, P=0.05) were the most significant risk factors for restrictive ventilatory defect. Vertebral anomalies were evident in 45 patients, predominating in the cervical spine in 38. The most significant risk factor for the occurrence of vertebral anomalies was any additional anomaly (OR 27, 95%C I8-100). Scoliosis (over 10 degrees) was observable in 56 patients, over 20 degrees in 11, and over 45 degrees in one. In the EA patients, risk for scoliosis over 10 degrees was 13-fold (OR 13, 95%CI 8.3-21) and over 20 degrees, 38-fold (OR 38, 95%CI 14-106) when compared to that of the general population. Thoracotomy-induced rib fusion (OR 3.6, 95%CI 0.7-19) and other associated anomalies (OR 2.1, 95%CI 0.9-2.9) were the strongest predictive factors for scoliosis. Significant esophageal morbidity associated with EA extends into adulthood. No association existed between the esophageal symptoms and histological findings. Surgical complications, increasing age, and impaired esophageal motility predicted development of epithelial metaplasia after repair of EA. According to our data, the risk for esophageal cancer is less than 500-fold that of the general population. However, the overall cancer incidence among adults with repaired EA did not differ from that of the general population. Adults with repaired EA have had significantly more respiratory symptoms and infections, as well as more asthma, and allergies than does the general population. Thoracotomy-induced rib fusion and GER-associated columnar epithelial metaplasia were the most significant risk factors for the restrictive ventilatory defect that occurred in over half the patients. Over half the patients with repaired EA are likely to develop scoliosis. Risk for scoliosis is 13-fold after repair of EA in relation to that of the general population. Nearly half the patients had vertebral anomalies. Most of these deformities were diagnosed neither in infancy nor during growth. The natural history of spinal deformities seems, however, rather benign, with spinal surgery rarely indicated.

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Without estrogen action, the fusion of the growth plates is postponed and statural growth continues for an exceptionally long time. Aromatase inhibitors, blockers of estrogen biosynthesis, have therefore emerged as a new potential option for the treatment of children with short stature. We investigated the efficacy of the aromatase inhibitor letrozole in the treatment of boys with idiopathic short stature (ISS) using a randomised, placebo-controlled, double-blind research setting. A total of 30 boys completed the two-year treatment. By decreasing estrogen-mediated central negative feedback, letrozole increased gonadotrophin and testosterone secretion in pubertal boys, whereas the pubertal increase in IGF-I was inhibited. Treatment with letrozole effectively delayed bone maturation and increased predicted adult height by 5.9 cm (P0.001), while placebo had no effect on either parameter. The effect of letrozole treatment on near-final height was studied in another population, in boys with constitutional delay of puberty, who received letrozole (n=9) or placebo (n=8) for one year, in combination with low-dose testosterone for six months during adolescence. The mean near-final height of boys randomised to receive testosterone and letrozole was significantly greater than that of boys who received testosterone and placebo (175.8 vs. 169.1 cm, P=0.04). As regards safety, treatment effects on bone health, lipid metabolism, insulin sensitivity, and body composition were monitored in boys with ISS. During treatment, no differences in bone mass accrual were evident between the treatment groups, as evaluated by dual-energy x-ray absorptiometry measurements of the lumbar spine and femoral neck. Bone turnover and cortical bone growth, however, were affected by letrozole treatment. As indicated by differences in markers of bone resorption (U-INTP) and formation (S-PINP and S-ALP), the long-term rate of bone turnover was lower in letrozole-treated boys, despite their more rapid advancement in puberty. Letrozole stimulated cortical bone growth in those who progressed in puberty: the metacarpal index (MCI), a measure of cortical bone thickness, increased more in letrozole-treated pubertal boys than in placebo-treated pubertal boys (25% vs. 9%, P=0.007). The change in MCI correlated positively with the mean testosterone-to-estradiol ratio. In post-treatment radiographic evaluation of the spine, a high rate of vertebral deformities - mild anterior wedging and mild compression deformities - were found in both placebo and letrozole groups. In pubertal boys with ISS treated with letrozole, stimulated testosterone secretion was associated with a decrease in the percentage of fat mass and in HDL-cholesterol, while LDL-cholesterol and triglycerides remained unchanged. Insulin sensitivity, as evaluated by HOMA-IR, was not significantly affected by the treatment. In summary, treatment with the aromatase inhibitor letrozole effectively delayed bone maturation and increased predicted adult height in boys with ISS. Long-term follow-up data of boys with constitutional delay of puberty, treated with letrozole for one year during adolescence, suggest that the achieved gain in predicted adult height also results in increased adult height. However, until the safety of aromatase inhibitor treatment in children and adolescents is confirmed, such treatment should be considered experimental.