973 resultados para R. Johnson
Resumo:
Eriophyid mites (Acari: Eriophyoidea: Eriophyidae: Rhombacus sp. and Acalox ptychocarpi Keifer) are recently-emerged pests of commercial eucalypt plantations in subtropical Australia. They cause severe blistering, necrosis and leaf loss to Corymbia citriodora subsp. variegata (F. Muell.) K.D. Hill & L.A.S. Johnson, one of the region's most important hardwood plantation species. In this study we examine the progression, incidence and severity of these damage symptoms. We also measure within-branch colonisation by mites to identify dispersive stages, and estimate the relative abundance of the two co-occurring species. Rhombacus sp., an undescribed species, was numerically dominant, accounting for over 90% of all adult mites. Adults were the dispersive stage, moving mostly within branches, but 12% of recruitment onto new leaves occurred on previously uninfested branches. Damage incidence and severity were correlated, while older leaves had more damage than younger leaves. "Patch-type" damage was less frequent but was associated with higher mite numbers and damage scores than "spot-type" damage, while leaf discoloration symptoms related mostly to leaf age.
Resumo:
Tutkielmassa tarkasteltiin opettajaksi opiskelevien koulumuistoja ja niissä esiintyviä positiivisia ja negatiivisia kokemuksia koulusta, oppimisesta ja opettajasta. Tutkimusmetodiksi valittiin koulumuistoista kirjoittaminen tarkoituksena helpottaa sekä kokemusten tuomista tietoisuuteen että niiden myöhempää käsittelyä kirjallisina dokumentteina. Opiskelijoita pyydettiin kirjoittamaan erään yhteisen luennon alussa parhaasta ja huonoimmasta koulumuistostaan. Tutkimuksen tarkoituksena oli kartoittaa opiskelijoiden muistoja koulusta. Tutkimuksen avulla pyrittiin myös osittain selittämään kokemuksien yhteyksiä toisiinsa. Tutkimusongelmina esitettiin seuraavat kysymykset: minkälaisia muistoja koulusta tulee ensimmäisenä mieleen, miten opettajan merkitys näkyy kyseisissä muistoissa, minkälaisen kuvan opiskelijoiden muistot antavat koulusta, ja miten muistoissa kuvatut koulukokemukset ovat mahdollisesti vaikuttaneet opiskelijoiden myöhempään elämään. Tutkimusjoukko koostui 101:stä Helsingin yliopiston opettajankoulutuslaitoksen ensimmäisen vuoden opiskelijasta, lastentarhanopettajan, luokanopettajan, kotitalousopettajan sekä käsityöopettajan koulutuslinjoilta. Koulumuistot sijoittuivat pääasiassa peruskouluaikaan, sillä opiskelijoista suurin osa oli alle 25-vuotiaita. Opiskelijoiden kirjoittamat muistot analysoitiin ja tulkittiin kvalitatiivisen tutkimusotteen mukaisesti. Analysointiluokkien muodostamiseen saatiin malli kahdesta aikaisemmasta tutkimuksesta. Ruotsalaisen Pérez Prieton koulukokemustutkimus ja amerikkalaisen Johnson Rothenbergin tutkimus opiskelijoiden koulumuistoista toimivat tämän tutkimuksen tärkeimpinä lähteinä teoriataustassa. Tutkimustulosten mukaan yli puolet opiskelijoiden koulumuistoista liittyi opettajaan. Opettajanvaikutus oli merkittävin negatiivisten muistojen kohdalla ja suurin osa maininnoista esiintyi nöyryytyskokemusten yhteydessä. Nöyryyttävinä koettiin tilanteet, joissa opettaja oli rankaissut julkisesti tai toiminut oppilaan oikeuksia vastaan. Positiivisissa muistoissa opettaja esiintyi noin viidesosassa maininnoista, pääasiassa menestymiskokemusten ja haastavuuden yhteydessä. Menestymiskokemukset,joihin liittyi yleensä itsensä toteuttamisen mahdollisuus, muodostivat suurimman parhaiden koulumuistojen luokan. Myös kaverit ja koulun ilmapiiri olivat merkittäviä tekijöitä niin hyvien kuin huonojenkin kokemusten kohdalla. Muita analysointiluokkia edellisten lisäksi olivat epäonnistuminen, turhautuminen, arvostelu, koulunvaihto ja rehtori. Teoreettisessa viitekehyksessä selvitettiin kokemuksen käsitettä ja sen soveltuvuutta tutkimuksen kohteeksi. Tärkeitä lähteitä tutkimuksen kokemuksellisen luonteen kannalta olivat Deweyn ja Jarvisin teokset, joissa käsiteltiin kokemuksen merkitystä kasvatukselle ja oppimiselle sekä reflektion vaikutusta kokemuksen merkittävyydelle. Lisäksi tarkasteltiin tutkimuksia koulukokemusten merkittävyydestä opettajaopiskelijoille ja opettajan merkityksestä oppilaalle tärkeänä aikuisena. Avainsanat: Koulumuistot, kokemusten tulkinta, opettajaopiskelijat, opettaja merkittävänä henkilönä Keywords: School Memories, Interpretation of Experiences, Future Teachers, Teacher as a Significant Person
Resumo:
The role of different chemical compounds, particularly organics, involved in the new particle formation (NPF) and its consequent growth are not fully understood. Therefore, this study was conducted to investigate the chemical composition of aerosol particles during NPF events in an urban subtropical environment. Aerosol chemical composition was measured along with particle number size distribution (PNSD) and several other air quality parameters at five sites across an urban subtropical environment. An Aerodyne compact Time-of-Flight Aerosol Mass Spectrometer (c-TOF-AMS) and a TSI Scanning Mobility Particle Sizer (SMPS) measured aerosol chemical composition (particles above 50 nm in vacuum aerodynamic diameter) and PNSD (particles within 9-414 nm in mobility diameter), respectively. Five NPF events, with growth rates in the range 3.3-4.6 nm, were detected at two of the sites. The NPF events happened on relatively warmer days with lower condensation sink (CS). Temporal percent fractions of organics increased after the particles grew enough to have a significant contribution to particles volume, while the mass fraction of ammonium and sulphate decreased. This uncovered the important role of organics in the growth of newly formed particles. Three organic markers, factors f43, f44 and f57, were calculated and the f44 vs f43 trends were compared between nucleation and non-nucleation days. K-means cluster analysis was performed on f44 vs f43 data and it was found that they follow different patterns on nucleation days compared to non-nucleation days, whereby f43 decreased for vehicle emission generated particles, while both f44 and f43 decreased for NPF generated particles. It was found for the first time that vehicle generated and newly formed particles cluster in different locations on f44 vs f43 plot and this finding can be potentially used as a tool for source apportionment of measured particles.
Resumo:
Nuclear hormone receptors, such as the ecdysone receptor, often display a large amount of induced fit to ligands. The size and shape of the binding pocket in the EcR subunit changes markedly on ligand binding, making modelling methods such as docking extremely challenging. It is, however, possible to generate excellent 3D QSAR models for a given type of ligand, suggesting that the receptor adopts a relatively restricted number of binding site configurations or [`]attractors'. We describe the synthesis, in vitro binding and selected in vivo toxicity data for [gamma]-methylene [gamma]-lactams, a new class of high-affinity ligands for ecdysone receptors from Bovicola ovis (Phthiraptera) and Lucilia cuprina (Diptera). The results of a 3D QSAR study of the binding of methylene lactams to recombinant ecdysone receptor protein suggest that this class of ligands is indeed recognized by a single conformation of the EcR binding pocket.
Resumo:
NMR studies of methyldichlorophosphine have been undertaken in the nematic phase of mixed liquid crystals of opposite diamagnetic anisotropies. The rα structure is derived. The proton chemical-shift anisotropy has been determined from the studies without the use of a reference compound and without a change of experimental conditions. It is shown that the molecule orients in the liquid crystal with positive diamagnetic anisotropy in such a way that the C3 symmetry axis of the CH3P moiety is preferentially aligned perpendicular to the direction of the magnetic field, unlike other similar systems. This is interpreted in terms of the formation of a weak solvent-solute molecular complex. The heteronuclear indirect spin-spin coupling constants are determined. The sign of the two-bond JPH is found to be positive.
Resumo:
Background/Aim There is a 70% higher age-adjusted incidence of heart failure (HF) amongst Aboriginal and Torres Strait Islander people, three times more hospitalisations and twice as many deaths than non-Aboriginal people. There is a need to develop holistic yet individualised approaches in accord with the values of Aboriginal community healthcare to support patient education and self-care. The aim of this study was to re-design an existing HF educational resource (Fluid Watchers-Pacific Rim©) to be culturally safe for Aboriginal and Torres Strait Islander peoples, working in collaboration with the local community, and to conduct feasibility testing. Methods This study was conducted in two phases and utilised a mixed methods approach (qualitative and quantitative). Phase 1 of this study used action research methods to develop a culturally safe electronic resource to be provided to Aboriginal HF patients via a tablet computer. A HF expert panel adapted the existing resource to ensure it was evidence-based and contained appropriate language and images that reflects Aboriginal culture. A stakeholder group (which included Aboriginal workers and HF patients, as well as researchers and clinicians) then reviewed the resources and changes were made accordingly. In Phase 2, the new resource was tested on a sample of Aboriginal HF patients to assess feasibility and acceptability. Patient knowledge, satisfaction and self-care behaviours were measured using a before and after design with validated questionnaires. As this was a pilot test to determine feasibility, no statistical comparisons were made. Results - Phase 1: Throughout the process of resource development, two main themes emerged from the stakeholder consultation. These were the importance of identity, meaning that it was important to ensure that the resource accurately reflected the local community, with the appropriate clothing, skin tone and voice. The resource was adapted to reflect this and of the local community voiced the recordings for the resource. The other theme was comprehension; images were important and all text was converted to the first person and used plain language. - Phase 2: Five Aboriginal participants, mean age 61.6 ± 10.0 years, with NYHA Class III and IV heart failure were enrolled. Participants reported a high level of satisfaction with the resource (83.0%). HF knowledge (percentage of correct responses) increased from 48.0 ± 6.7% to 58.0 ± 9.7%, a 20.8% increase and results of the self-care index indicated that the biggest change was in patient confidence for self-care with a 95% increase in confidence score (46.7 ± 16.0 to 91.1 ± 11.5). Changes in management and maintenance scores varied between9275 patients. Conclusion By working in collaboration with HF experts, Aboriginal researchers and patients, a culturally safe HF resource has been developed for Aboriginal and Torres Strait Islander patients. Engaging Aboriginal researchers, capacity-building, and being responsive to local systems and structures enabled this pilot study to be successfully completed with the Aboriginal community and positive participant feedback demonstrated that the methodology used in this study was appropriate and acceptable; participants were able to engage with willingness and confidence.
Resumo:
A proposal has been posted on the ICTV website (2011.001aG.N.v1.binomial_sp_names) to replace virus species names by non-Latinized binomial names consisting of the current italicized species name with the terminal word "virus" replaced by the italicized and non-capitalized genus name to which the species belongs. If implemented, the current italicized species name Measles virus, for instance, would become Measles morbillivirus while the current virus name measles virus and its abbreviation MeV would remain unchanged. The rationale for the proposed change is presented.
Resumo:
Digital Image
Resumo:
Digital Image
Resumo:
Digital Image
Resumo:
Digital Image
Resumo:
Digital Image
Resumo:
Digital Image
Resumo:
Digital Image