99 research outputs found
Geometric analysis of satellite laser ranging data
The analysis of simultaneous laser data is investigated using the method of trilateration. Analysis of data from 1987 to 1992 is presented with selected baseline rates and station positions. The use of simultaneous Etalon data is simulated to demonstrate the additional global coverage these satellites provide. Trilateration has a great potential for regional deformation studies with monthly LAGEOS American solutions between 3-12 millimeters
Reply
No abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78300/1/20291_ftp.pd
Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design
<p>Abstract</p> <p>Background</p> <p>The green peach aphid, <it>Myzus persicae </it>(Sulzer), is a world-wide insect pest capable of infesting more than 40 plant families, including many crop species. However, despite the significant damage inflicted by <it>M. persicae </it>in agricultural systems through direct feeding damage and by its ability to transmit plant viruses, limited genomic information is available for this species.</p> <p>Results</p> <p>Sequencing of 16 <it>M. persicae </it>cDNA libraries generated 26,669 expressed sequence tags (ESTs). Aphids for library construction were raised on <it>Arabidopsis thaliana</it>, <it>Nicotiana benthamiana</it>, <it>Brassica oleracea, B. napus</it>, and <it>Physalis floridana </it>(with and without <it>Potato leafroll virus </it>infection). The <it>M. persicae </it>cDNA libraries include ones made from sexual and asexual whole aphids, guts, heads, and salivary glands. <it>In silico </it>comparison of cDNA libraries identified aphid genes with tissue-specific expression patterns, and gene expression that is induced by feeding on <it>Nicotiana benthamiana</it>. Furthermore, 2423 genes that are novel to science and potentially aphid-specific were identified. Comparison of cDNA data from three aphid lineages identified single nucleotide polymorphisms that can be used as genetic markers and, in some cases, may represent functional differences in the protein products. In particular, non-conservative amino acid substitutions in a highly expressed gut protease may be of adaptive significance for <it>M. persicae </it>feeding on different host plants. The Agilent eArray platform was used to design an <it>M. persicae </it>oligonucleotide microarray representing over 10,000 unique genes.</p> <p>Conclusion</p> <p>New genomic resources have been developed for <it>M. persicae</it>, an agriculturally important insect pest. These include previously unknown sequence data, a collection of expressed genes, molecular markers, and a DNA microarray that can be used to study aphid gene expression. These resources will help elucidate the adaptations that allow <it>M. persicae </it>to develop compatible interactions with its host plants, complementing ongoing work illuminating plant molecular responses to phloem-feeding insects.</p
The solvation and dissociation of 4-benzylaniline hydrochloride in chlorobenzene
A reaction scheme is proposed to account for the liberation of 4-benzylaniline from 4-benzylaniline hydrochloride, using chlorobenzene as a solvent at a temperature of 373 K. Two operational regimes are explored: “closed” reaction conditions correspond to the retention of evolved hydrogen chloride gas within the reaction medium, whereas an “open” system permits gaseous hydrogen chloride to be released from the reaction medium. The solution phase chemistry is analyzed by 1H NMR spectroscopy. Complete liberation of solvated 4-benzylaniline from solid 4-benzylaniline hydrochloride is possible under “open” conditions, with the entropically favored conversion of solvated hydrogen chloride to the gaseous phase thought to be the thermodynamic driver that effectively controls a series of interconnecting equilibria. A kinetic model is proposed to account for the observations of the open system
Recommended from our members
Outcomes in patients with gunshot wounds to the brain.
Introduction:Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR. Methods:We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation. Results:825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation. Conclusion:We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition. Level of evidence:Level II
Oral steroids for hearing loss associated with otitis media with effusion in children aged 2–8 years: the OSTRICH RCT
Background Children with hearing loss associated with otitis media with effusion (OME) are commonly managed through surgical intervention, hearing aids or watchful waiting. A safe, inexpensive, effective medical treatment would enhance treatment options. Small, poorly conducted trials have found a short-term benefit from oral steroids. Objective To determine the clinical effectiveness and cost-effectiveness of a 7-day course of oral steroids in improving hearing at 5 weeks in children with persistent OME symptoms and current bilateral OME and hearing loss demonstrated by audiometry. Design Double-blind, individually randomised, placebo-controlled trial. Setting Ear, nose and throat outpatient or paediatric audiology and audiovestibular medicine clinics in Wales and England. Participants Children aged 2–8 years, with symptoms of hearing loss attributable to OME for at least 3 months, a diagnosis of bilateral OME made on the day of recruitment and audiometry-confirmed hearing loss. Interventions A 7-day course of oral soluble prednisolone, as a single daily dose of 20 mg for children aged 2–5 years or 30 mg for 6- to 8-year-olds, or matched placebo. Main outcome measures Acceptable hearing at 5 weeks from randomisation. Secondary outcomes comprised acceptable hearing at 6 and 12 months, tympanometry, otoscopic findings, health-care consultations related to OME and other resource use, proportion of children who had ventilation tube (grommet) surgery at 6 and 12 months, adverse effects, symptoms, functional health status, health-related quality of life, short- and longer-term cost-effectiveness. Results A total of 389 children were randomised. Satisfactory hearing at 5 weeks was achieved by 39.9% and 32.8% in the oral steroid and placebo groups, respectively (absolute difference of 7.1%, 95% confidence interval –2.8% to 16.8%; number needed to treat = 14). This difference was not statistically significant. The secondary outcomes were consistent with the picture of a small or no benefit, and we found no subgroups that achieved a meaningful benefit from oral steroids. The economic analysis showed that treatment with oral steroids was more expensive and accrued fewer quality-adjusted life-years than treatment as usual. However, the differences were small and not statistically significant, and the sensitivity analyses demonstrated large variation in the results. Conclusions OME in children with documented hearing loss and attributable symptoms for at least 3 months has a high rate of spontaneous resolution. Discussions about watchful waiting and other interventions will be enhanced by this evidence. The findings of this study suggest that any benefit from a short course of oral steroids for OME is likely to be small and of questionable clinical significance, and that the treatment is unlikely to be cost-effective and, therefore, their use cannot be recommended
The medical student
The Medical Student was published from 1888-1921 by the students of Boston University School of Medicine
Crop Updates 2007 - Cereals
This session covers twenty six papers from different authors:
CEREAL BREEDING
1. Strategies for aligning producer and market imperatives in cereal breeding in Western Australia, R. Loughman, R. Lance, I. Barclay, G. Crosbie, S. Harasymow, W. Lambe, C. Li, R. McLean, C. Moore, K. Stefanova, A. Tarr and R. Wilson, Department of Agriculture and Food
2. LongReach plant breeders wheat variety trials – 2006, Matu Peipi and Matt Whiting, LongReach Plant Breeders
WHEAT AGRONOMY
3. Response of wheat varieties to sowing time in the northern agricultural region in 2006, Christine Zaicou, Department of Agriculture and Food
4. Response of wheat varieties to sowing time in the central agricultural region in 2006, Shahajahan Miyan, Department of Agriculture and Food
5. Response of wheat varieties to sowing time in the Great Southern and Lakes region, Brenda Shackleyand Ian Hartley, Department of Agriculture and Food
6. Response of wheat varieties to time of sowing time in Esperance region in 2006, Christine Zaicou, Ben Curtis and Ian Hartley, Department of Agriculture and Food
7. Performance of wheat varieties in National Variety Testing (NVT) WA: Year 2, Peter Burgess, Agritech Crop Research
8. Flowering dates of wheat varieties in Western Australia in 2006, Darshan Sharma, Brenda Shackley and Christine Zaicou, Department of Agriculture and Food
9. Prospects for perennial wheat: A feasibility study, Len J. Wade, Lindsay W. Bell, Felicity Byrne (nee Flugge) and Mike A. Ewing, School of Plant Biology and CRC for Plant-based Management of Dryland Salinity, The University of Western Australia
BARLEY AGRONOMY
10. Barley agronomy highlights: Time of sowing x variety, Blakely Paynter and Andrea Hills, Department of Agriculture and Food
11. Barley agronomy highlights: Weeds and row spacing, Blakely Paynter and Andrea Hills, Department of Agriculture and Food
12. Barley agronomy highlights: Weeds and barley variety, Blakely Paynter and Andrea Hills, Department of Agriculture and Food
OAT AGRONOMY
13. Agronomic performance of dwarf potential milling oat varieties in varied environments of WA, Raj Malik, Blakely Paynter and Kellie Winfield, Department of Agriculture and Food
14. Sourcing oat production information in 2007, Kellie Winfield, Department of Agriculture and Food
HERBICIDE TOLERANCE
15. Response of new wheat varieties to herbicides, Harmohinder Dhammu, Department of Agriculture and Food
16. Herbicide tolerance of new barley varieties, Harmohinder Dhammu, Vince Lambert and Chris Roberts, Department of Agriculture and Food
17. Herbicide tolerance of new oat varieties, Harmohinder Dhammu, Vince Lambert and Chris Roberts, Department of Agriculture and Food
NUTRITION
18. Nitrogen Decision Tools – choose your weapon, Jeremy Lemon, Department of Agriculture and Food
DISEASES
19. Barley agronomy highlights: Canopy management, Andrea Hills and Blakely Paynter, Department of Agriculture and Food
20. Barley agronomy highlights: Leaf diseases and spots, Andrea Hills and Blakely Paynter, Department of Agriculture and Food
21. Fungicide applications for stripe rust management in adult plant resistant (APR) wheat varieties, Geoff Thomas, Rob Loughman, Ian Hartley and Andrew Taylor; Department of Agriculture and Food
22. Effect of seed treatment with Jockey on time of onset and disease severity of stripe rust in wheat, Manisha Shankar, John Majewski and Rob Loughman, Department of Agriculture and Food
23. Rotations for management of Cereal Cyst Nematode, Vivien Vanstone, Department of Agriculture and Food
24. Occurrence of Wheat Streak Mosaic Virus in Western Australian grainbelt during the 2006 growing season, Brenda Coutts, Monica Kehoe and Roger Jones, Department of Agriculture and Food
25. Development of a seed test for Wheat Streak Mosaic Virus in bulk samples of wheat, Geoffrey Dwyer, Belinda Welsh, Cuiping Wang and Roger Jones, Department of Agriculture and Food
MARKETS
26. Developing the Australian barley value chain, Linda Price, Barley Australi
Harnessing landrace diversity empowers wheat breeding
Harnessing genetic diversity in major staple crops through the development of new breeding capabilities is essential to ensure food security1. Here we examined the genetic and phenotypic diversity of the A.E. Watkins landrace collection2 of bread wheat (Triticum aestivum), a major global cereal, through whole-genome re-sequencing (827 Watkins landraces and 208 modern cultivars) and in-depth field evaluation spanning a decade. We discovered that modern cultivars are derived from just two of the seven ancestral groups of wheat and maintain very long-range haplotype integrity. The remaining five groups represent untapped genetic sources, providing access to landrace-specific alleles and haplotypes for breeding. Linkage disequilibrium (LD) based haplotypes and association genetics analyses link Watkins genomes to the thousands of high-resolution quantitative trait loci (QTL), and significant marker-trait associations identified. Using these structured germplasm, genotyping and informatics resources, we revealed many Watkins-unique beneficial haplotypes that can confer superior traits in modern wheat. Furthermore, we assessed the phenotypic effects of 44,338 Watkins-unique haplotypes, introgressed from 143 prioritised QTL in the context of modern cultivars, bridging the gap between landrace diversity and current breeding. This study establishes a framework for systematically utilising genetic diversity in crop improvement to achieve sustainable food security.</p
- …