985 resultados para 126-793


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The anti-T lectin from peanut (Arachis hypogaea) crystallizes in the orthorhombic space group P21212 with one tetrameric molecule (Mr 110,000) in the asymmetric unit in a cell of dimensions a = 129.3 Å, B = 126.9 Å and C = 76.9 Å. The crystals are suitable for high resolution work.

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Spontaneous sequence changes and the selection of beneficial mutations are driving forces of gene diversification and key factors of evolution. In highly dynamic co-evolutionary processes such as plant-pathogen interactions, the plant's ability to rapidly adapt to newly emerging pathogens is paramount. The hexaploid wheat gene Lr34, which encodes an ATP-binding cassette (ABC) transporter, confers durable field resistance against four fungal diseases. Despite its extensive use in breeding and agriculture, no increase in virulence towards Lr34 has been described over the last century. The wheat genepool contains two predominant Lr34 alleles of which only one confers disease resistance. The two alleles, located on chromosome 7DS, differ by only two exon-polymorphisms. Putatively functional homoeologs and orthologs of Lr34 are found on the B-genome of wheat and in rice and sorghum, but not in maize, barley and Brachypodium. In this study we present a detailed haplotype analysis of homoeologous and orthologous Lr34 genes in genetically and geographically diverse selections of wheat, rice and sorghum accessions. We found that the resistant Lr34 haplotype is unique to the wheat D-genome and is not found in the B-genome of wheat or in rice and sorghum. Furthermore, we only found the susceptible Lr34 allele in a set of 252 Ae. tauschii genotypes, the progenitor of the wheat D-genome. These data provide compelling evidence that the Lr34 multi-pathogen resistance is the result of recent gene diversification occurring after the formation of hexaploid wheat about 8,000 years ago.

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Nested association mapping (NAM) offers power to dissect complex, quantitative traits. This study made use of a recently developed sorghum backcross (BC)-NAM population to dissect the genetic architecture of flowering time in sorghum; to compare the QTL identified with other genomic regions identified in previous sorghum and maize flowering time studies and to highlight the implications of our findings for plant breeding. A subset of the sorghum BC-NAM population consisting of over 1,300 individuals from 24 families was evaluated for flowering time across multiple environments. Two QTL analysis methodologies were used to identify 40 QTLs with predominately small, additive effects on flowering time; 24 of these co-located with previously identified QTL for flowering time in sorghum and 16 were novel in sorghum. Significant synteny was also detected with the QTL for flowering time detected in a comparable NAM resource recently developed for maize (Zea mays) by Buckler et al. (Science 325:714-718, 2009). The use of the sorghum BC-NAM population allowed us to catalogue allelic variants at a maximal number of QTL and understand their contribution to the flowering time phenotype and distribution across diverse germplasm. The successful demonstration of the power of the sorghum BC-NAM population is exemplified not only by correspondence of QTL previously identified in sorghum, but also by correspondence of QTL in different taxa, specifically maize in this case. The unification across taxa of the candidate genes influencing complex traits, such as flowering time can further facilitate the detailed dissection of the genetic control and causal genes.

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Root architecture traits in wheat are important in deep soil moisture acquisition and may be used to improve adaptation to water-limited environments. The genetic architecture of two root traits, seminal root angle and seminal root number, were investigated using a doubled haploid population derived from SeriM82 and Hartog. Multiple novel quantitative trait loci (QTL) were identified, each one having a modest effect. For seminal root angle, four QTL (-log10(P) >3) were identified on 2A, 3D, 6A and 6B, and two suggestive QTL (-log10(P) >2) on 5D and 6B. For root number, two QTL were identified on 4A and 6A with four suggestive QTL on 1B, 3A, 3B and 4A. QTL for root angle and root number did not co-locate. Transgressive segregation was found for both traits. Known major height and phenology loci appear to have little effect on root angle and number. Presence or absence of the T1BL.1RS translocation did not significantly influence root angle. Broad sense heritability (h 2) was estimated as 50 % for root angle and 31 % for root number. Root angle QTL were found to be segregating between wheat cultivars adapted to the target production region indicating potential to select for root angle in breeding programs. © 2013 Springer-Verlag Berlin Heidelberg.

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Eucalyptus argophloia Blakely (Western white gum) has shown potential as a commercial forestry timber species in marginal environments of north-eastern Australia. We measured early pollination success in Eucalyptus argophloia to compare pollination methods, determine the timing of stigma receptivity and compare fresh and stored pollen. Early pollination success was measured by counting pollen tubes in the style of E. argophloia 12 days after pollination. We compared the early pollination success of 1) Artificially Induced Protogyny (AIP), one-stop and three-stop methods of pollination; 2) flowers pollinated at 2 day intervals between 2 days before and 6 days after anthesis and 3) fresh pollen and pollen that had been stored for 9 months. Our results show significantly more pollen tubes from unpollinated AIP and AIP treatments than either the one-stop pollination or three-stop pollination treatments. This indicates that self-pollination occurs in the unpollinated AIP treatment. There was very little pollen tube growth in the one-stop method indicating that the three-stop method is the most suitable for this species. Stigma receptivity in E. argophloia commenced six days after anthesis and no pollen tube growth was observed prior to this. Fresh pollen resulted in pollen tube growth in the style whereas the stored pollen resulted in a total absence of pollen tube growth. We recommend that breeding programs incorporating E. argophloia as a female parent use the three-stop pollination method, and controlled pollination be carried out at least six days after anthesis using fresh pollen.

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Impulsivity and hyperactivity share common ground with numerous mental disorders, including schizophrenia. Recently, a population-specific serotonin 2B (5-HT2B) receptor stop codon (ie, HTR2B Q20*) was reported to segregate with severely impulsive individuals, whereas 5-HT2B mutant (Htr2B−/−) mice also showed high impulsivity. Interestingly, in the same cohort, early-onset schizophrenia was more prevalent in HTR2B Q*20 carriers. However, the putative role of 5-HT2B receptor in the neurobiology of schizophrenia has never been investigated. We assessed the effects of the genetic and the pharmacological ablation of 5-HT2B receptors in mice subjected to a comprehensive series of behavioral test screenings for schizophrenic-like symptoms and investigated relevant dopaminergic and glutamatergic neurochemical alterations in the cortex and the striatum. Domains related to the positive, negative, and cognitive symptom clusters of schizophrenia were affected in Htr2B−/− mice, as shown by deficits in sensorimotor gating, in selective attention, in social interactions, and in learning and memory processes. In addition, Htr2B−/− mice presented with enhanced locomotor response to the psychostimulants dizocilpine and amphetamine, and with robust alterations in sleep architecture. Moreover, ablation of 5-HT2B receptors induced a region-selective decrease of dopamine and glutamate concentrations in the dorsal striatum. Importantly, selected schizophrenic-like phenotypes and endophenotypes were rescued by chronic haloperidol treatment. We report herein that 5-HT2B receptor deficiency confers a wide spectrum of antipsychotic-sensitive schizophrenic-like behavioral and psychopharmacological phenotypes in mice and provide first evidence for a role of 5-HT2B receptors in the neurobiology of psychotic disorders

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Chromolaena odorata (L.) King and Robinson (Asteraceae) is a significant agricultural weed in Papua New Guinea (PNG), affecting plantations, food gardens and grazing lands. It was the focus of a collaborative biocontrol program funded by the Australian Government between 1998 and 2007. Chromolaena was recorded at 680 sites in 13 provinces of PNG through surveys, field releases of biocontrol agents and feedback from public awareness programs. Three biocontrol agents, the moth Pareuchaetes pseudoinsulata Rego Barros (Lepidoptera: Arctiidae), the stemgalling fly Cecidochares connexa (Macquart) (Diptera: Tephritidae) and the leaf mining fly Calycomyza eupatorivora Spencer (Diptera: Agromyzidae), were introduced to control chromolaena. Cecidochares connexa was found to be the most effective of the agents introduced as it quickly established at over 300 sites where it was released and spread up to 100km in five years from some sites. Experimental field plots established to determine the impact of the agents on chromolaena, showed that the size of chromolaena infestations decreased with the presence of C. connexa. A survey was conducted to quantify the social and economic benefits of biocontrol of chromolaena to landholders. Chromolaena is considered to be under substantial/significant control in nine provinces in PNG, with about 50% of respondents stating that there is less than 50% of chromolaena remaining following the release of the gall fly. This has resulted in landholders spending less time clearing chromolaena and the re-establishment of small-scale subsistence farms and the regeneration of natural vegetation. Crop yield and income generated from the sale of agricultural produce have increased by at least 50% since chromolaena was brought under biocontrol. It is anticipated that the gall fly will continue to spread and control chromolaena in areas where it has not yet reached, thereby further reducing the impact of the weed in PNG.

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Tässä työssä selvitetään lentosääennusteiden käyttöä lennon suunnittelun ja toteutuksen perusteena. Tuodaan esille määräyksiä ja lentosäätietojen käyttöä kaikissa lennon vaiheissa. Perehdytään ennustettujen olosuhteiden ja ennusteiden laadun merkitykseen lentojen toteutuksessa. Selvitetään lentosääennusteisiin liittyviä lentoliikenteen kustannuksia. Työn aineistona käytettiin joulukuu 2006 - heinäkuu 2007 välisenä aikana eri pituisina jaksoina kerättyä 185 liikennelennon lennonsuunnittelumateriaalia ja 126 satunnaisella otoksella otettuja Suomen GAFOR -ennusteita. Liikennelennot toteutettiin Suomen ja Euroopan alueella. Työssä todennettiin METAR –lentopaikkasanoman avulla TAF -lentopaikka-, TREND -laskeutumis-, GAFOR -yleisilmailuennusteita. Yleisestä sääpalvelusta saatua materiaalia käsiteltiin EXCEL –taulukkolaskentaohjelmalla Lentosääennusteita käsiteltiin usean eri käyttäjäryhmän kannalta. Reittilentomittauksilla tutkittiin SIGMET –varoituspalvelun, SWC –merkitsevän sään ja yläilmakehän tuulen sekä lämpötilan ennusteita. TAF –pilvikorkeusennusteiden keskimääräinen hyvyysluku oli lähes sama pilvikorkeudesta riippumatta. Suhteellisen hyvissä olosuhteissa toimivat käyttäjät saivat ennusteista paljon hyötyä. Vaakanäkyvyysennusteiden keskimääräinen hyvyysluku oli suurempi hyvissä kuin huonoissa olosuhteissa. Huonojen olosuhteiden ennusteet olivat lentotoiminnalle enemmän harmillisia kuin hyödyllisiä. Ennustustyö olisi tarvinnut apuvälinettä. Tutkittiin TREND –ennusteiden ominaista osuvuutta. NOSIG –ennuste oli suhteellisen usein julkaistu vaikka sitä seurasi olosuhteen muutos. BECMG -ennuste toteutui pääsääntöisesti ennusteajan alkupuolella. Ajoittaisten olosuhdemuutosten aikana TEMPO -ennusteita julkaistiin hyvin, mutta ennusteen osuvuus vaihteli. Tässä muodossa jaettu ennustetieto ei palvele kovin hyvin päätöstilannetta, jossa on arvioitava polttoaineen riittävyys lennon loppuosalle. GAFOR -pintatuuliennusteet olivat onnistuneita kuten TAF -ennusteissa. Vaakanäkyvyys- ja pilvikorkeusolosuhteissa vertailupisteissä oli 10% havainnoista ennustettua huonompaa olosuhdetta, jos käytettiin vain GAFOR –ennusteen perusosaa lennonsuunnittelussa ja 6% havainnoista, jos käytettiin koko ennustetta. Ilma-aluksen päällikön on valvottava näkölento-olosuhteiden kehitystä lennon aikana ja varmistettava aina näkölento-olosuhteinen lentoreitti laskupaikalle. Lentosääennusteet ovat osa lentotoimintaa mahdollistavaa järjestelmää. Ennusteet hallitsevat vaihtelevasti olosuhteita ja luonnollisesti aiheuttavat ongelmallisia tilanteita. Käyttäjiä sitovat määräykset on luotu, jotta toiminta olisi turvallista. Laadukkaita ennusteita tarvitaan isoilla liikennepaikoilla lentoliikenteen kapasiteetin hallintaan. Pienillä lentopaikoilla laitevarustus ei vielä takaa lentotoimintaa kaikissa olosuhteissa. Näkölentotoimintaa harjoitetaan jatkuvasti sekä hyvissä että kohtalaisen huonoissa olosuhteissa.

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Correspondence, clippings, manuscripts, notes, reports, relating to Bernstein's journalistic, literary and diplomatic careers. Correspondence with well-known literary, political and communal, society personalities, 1908-1935. Includes Cyrus Adler, Viscount Allenby, Joseph Barondess, Bernard Baruch, Henri Bergson, Hayyim Nahman Bialik, Jacob Billikopf, Vladimir Bourtzeff, Louis Brandeis, Robert Cecil, Fyodor Chaliapin, Jacob de Haas, Albert Einstein, Henry Ford, Felix Frankfurter, Herbert Hoover, Vladimir Jabotinsky, Horace M. Kallen, Peretz Hirschbein, Peter Kropotkin, Herbert Lehman, Louis Lipsky, Judah L. Magnes, Louis Marshall, Henry Morgenthau, Max Nordau, Adolph Simon Ochs, David de Sola Pool, Bernard G. Richards, Theodore Roosevelt, Julius Rosenwald, Jacob Schiff, Harry Schneiderman, Maurice Schwartz, George Bernard Shaw, Sholem Aleichem, Nathan Straus, Henrietta Szold, Chaim Tchernowitz, Leo Tolstoy, Samuel Untermyer, Henry Van Dyke, Lillian Wald, Felix Warburg, Chaim Weizman n, Jefferson Williams, Stephen Wise, Israel Zangwill. Correspondence and other materials relating to Bernstein's post as U.S. ambassador to Albania. Materials pertaining to Bernstein's editorial work at *The Day*, *Jewish Tribune*, *New York Herald*, *Jewish Daily Bulletin*. Materials pertaining to Bernstein's involvement with the American Jewish Committee. Correspondence with organizations including American Jewish Congress, *American Hebrew*, HIAS, *Jewish Chronicle* (London), Jewish Community of New York, *Menorah Journal*, *New York American*, *New York Times*, ORT, U.S. Dept. of State, Yiddish Art Theater, Zionist Organization of America. Articles, clippings, correspondence and court materials relating to the Ford libel suit. Miscellaneous documents and reports relating to the Paris Peace Conference, the Jewish situation in Russia, 1917-1920, Russian revolutionary events of 1917. News dispatches from Russia, 1917-1920s. Translations by Bernstein of Russian wri Andre yev,

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Glaucoma is the second leading cause of blindness worldwide. Often, the optic nerve head (ONH) glaucomatous damage and ONH changes occur prior to visual field loss and are observable in vivo. Thus, digital image analysis is a promising choice for detecting the onset and/or progression of glaucoma. In this paper, we present a new framework for detecting glaucomatous changes in the ONH of an eye using the method of proper orthogonal decomposition (POD). A baseline topograph subspace was constructed for each eye to describe the structure of the ONH of the eye at a reference/baseline condition using POD. Any glaucomatous changes in the ONH of the eye present during a follow-up exam were estimated by comparing the follow-up ONH topography with its baseline topograph subspace representation. Image correspondence measures of L-1-norm and L-2-norm, correlation, and image Euclidean distance (IMED) were used to quantify the ONH changes. An ONH topographic library built from the Louisiana State University Experimental Glaucoma study was used to evaluate the performance of the proposed method. The area under the receiver operating characteristic curves (AUCs) was used to compare the diagnostic performance of the POD-induced parameters with the parameters of the topographic change analysis (TCA) method. The IMED and L-2-norm parameters in the POD framework provided the highest AUC of 0.94 at 10 degrees. field of imaging and 0.91 at 15 degrees. field of imaging compared to the TCA parameters with an AUC of 0.86 and 0.88, respectively. The proposed POD framework captures the instrument measurement variability and inherent structure variability and shows promise for improving our ability to detect glaucomatous change over time in glaucoma management.

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Summer in the Persian Gulf region presents physiological challenges for Australian sheep that are part of the live export supply chain coming from the Australian winter. Many feedlots throughout the Gulf have very high numbers of animals during June to August in order to cater for the increased demand for religious festivals. From an animal welfare perspective it is important to understand the necessary requirements of feed and water trough allowances, and the amount of pen space required, to cope with exposure to these types of climatic conditions. This study addresses parameters that are pertinent to the wellbeing of animals arriving in the Persian Gulf all year round. Three experiments were conducted in a feedlot in the Persian Gulf between March 2010 and February 2012, totalling 44 replicate pens each with 60 or 100 sheep. The applied treatments covered animal densities, feed-bunk lengths and water trough lengths. Weights, carcass attributes and health status were the key recorded variables. Weight change results showed superior performance for animal densities of ≥1.2 m2/head during hot conditions (24-h average temperatures greater than 33 °C, or a diurnal range of around 29–37 °C). However the space allowance for animals can be decreased, with no demonstrated detrimental effect, to 0.6 m2/head under milder conditions. A feed-bunk length of ≥5 cm/head is needed, as 2 cm/head showed significantly poorer animal performance. When feeding at 90 ad libitum 10 cm/head was optimal, however under a maintenance feeding regime (1 kg/head/day) 5 cm/head was adequate. A minimum water trough allowance of 1 cm/head is required. However, this experiment was conducted during milder conditions, and it may well be expected that larger water trough lengths would be needed in hotter conditions. Carcass weights were determined mainly by weights at feedlot entry and subsequent weight gains, while dressing percentage was not significantly affected by any of the applied treatments. There was no demonstrated effect of any of the treatments on the number of animals that died, or were classified as unwell. However, across all the treatments, these animals lost significantly more weight than the healthy animals, so the above recommendations, which are aimed at maintaining weight, should also be applicable for good animal health and welfare. Therefore, best practice guidelines for managing Australian sheep in Persian Gulf feedlots in the hottest months (June–August) which present the greatest environmental and physical challenge is to allow feed-bunk length 5 cm/head on a maintenance-feeding program and 10 cm/head for 90 ad libitum feeding, and the space allowance per animal should be ≥1.2 m2/head. Water trough allocation should be at least 1 cm/head with provision for more in the summer when water intake potentially doubles.

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Summer in the Persian Gulf region presents physiological challenges for Australian sheep that are part of the live export supply chain coming from the Australian winter. Many feedlots throughout the Gulf have very high numbers of animals during June to August in order to cater for the increased demand for religious festivals. From an animal welfare perspective it is important to understand the necessary requirements of feed and water trough allowances, and the amount of pen space required, to cope with exposure to these types of climatic conditions. This study addresses parameters that are pertinent to the wellbeing of animals arriving in the Persian Gulf all year round. Three experiments were conducted in a feedlot in the Persian Gulf between March 2010 and February 2012, totalling 44 replicate pens each with 60 or 100 sheep. The applied treatments covered animal densities, feed-bunk lengths and water trough lengths. Weights, carcass attributes and health status were the key recorded variables. Weight change results showed superior performance for animal densities of ≥1.2 m2/head during hot conditions (24-h average temperatures greater than 33 °C, or a diurnal range of around 29–37 °C). However the space allowance for animals can be decreased, with no demonstrated detrimental effect, to 0.6 m2/head under milder conditions. A feed-bunk length of ≥5 cm/head is needed, as 2 cm/head showed significantly poorer animal performance. When feeding at 90% ad libitum 10 cm/head was optimal, however under a maintenance feeding regime (1 kg/head/day) 5 cm/head was adequate. A minimum water trough allowance of 1 cm/head is required. However, this experiment was conducted during milder conditions, and it may well be expected that larger water trough lengths would be needed in hotter conditions. Carcass weights were determined mainly by weights at feedlot entry and subsequent weight gains, while dressing percentage was not significantly affected by any of the applied treatments. There was no demonstrated effect of any of the treatments on the number of animals that died, or were classified as unwell. However, across all the treatments, these animals lost significantly more weight than the healthy animals, so the above recommendations, which are aimed at maintaining weight, should also be applicable for good animal health and welfare. Therefore, best practice guidelines for managing Australian sheep in Persian Gulf feedlots in the hottest months (June–August) which present the greatest environmental and physical challenge is to allow feed-bunk length 5 cm/head on a maintenance-feeding program and 10 cm/head for 90% ad libitum feeding, and the space allowance per animal should be ≥1.2 m2/head. Water trough allocation should be at least 1 cm/head with provision for more in the summer when water intake potentially doubles.

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Techniques to improve upon the design of two-dimensional encoding masks for multiplex Hadamard spectrometric imagers are described. The technique to generate masks based on completely orthonormal codes is described. In some cases, selfsupporting masks result which were not previously known. Transmission through the encoding masks (but not necessarily the signalto-noise ratio) can also be increased.