992 resultados para H 800 R425r


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This cross-sectional study analyzed psychological well-being at school using the Self-Determination theory as a theoretical frame-work. The study explored basic psychological needs fulfillment (BPNS), academic (SRQ-A), prosocial self-regulation (SRQ-P) and motivation, and their relationship with achievement in general, special and selective education (N=786, 444 boys, 345 girls, mean age 12 yrs 8 mths). Motivation starts behavior which becomes guided by self-regulation. The perceived locus of control (PLOC) affects how self-determined this behavior will be; in other words, to what extent it is autonomously regulated. In order learn and thus to be able to accept external goals, a student has to feel emotionally safe and have sufficient ego-flexibility—all of which builds on satisfied psychological needs. In this study those conditions were explored. In addition to traditional methods Self-organizing maps (SOM), was used in order to cluster the students according to their well-being, self-regulation, motivation and achievement scores. The main impacts of this research were: a presentation of the theory based alternative of studying psychological well-being at school and usage of both the variable and person-oriented approach. In this Finnish sample the results showed that the majority of students felt well, but the well-being varied by group. Overall about for 11–15% the basic needs were deprived depending on the educational group. Age and educational group were the most effective factors; gender was important in relation to prosocial identified behavior. Although the person-oriented SOM-approach, was in a large extent confirming what was no-ticed by using comparison of the variables: the SEN groups had lower levels of basic needs fulfillment and less autonomous self-regulation, interesting deviations of that rule appeared. Some of the SEL- and GEN-group members ended up in the more unfavorable SOM-clusters, and not all SEN-group members belonged to the poorest clusters (although not to the best either). This evidence refines the well-being and self-regulation picture, and may re-direct intervention plans, and turn our focus also on students who might otherwise remain unnoticed. On the other hand, these results imply simultaneously that in special education groups the average is not the whole truth. On the basis of theoretical and empirical considerations an intervention model was sug-gested. The aim of the model was to shift amotivation or external motivation in a more intrinsic direction. According to the theoretical and empirical evidence this can be achieved first by studying the self-concept a student has, and then trying to affect both inner and environmental factors—including a consideration of the basic psychological needs. Keywords: academic self-regulation, prosocial self-regulation, basic psychological needs, moti-vation, achievement

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When exposed to hot (22-35 degrees C) and dry climatic conditions in the field during the final 4-6 weeks of pod filling, peanuts (Arachis hypogaea L.) can accumulate highly carcinogenic and immuno-suppressing aflatoxins. Forecasting of the risk posed by these conditions can assist in minimizing pre-harvest contamination. A model was therefore developed as part of the Agricultural Production Systems Simulator (APSIM) peanut module, which calculated an aflatoxin risk index (ARI) using four temperature response functions when fractional available soil water was <0.20 and the crop was in the last 0.40 of the pod-filling phase. ARI explained 0.95 (P <= 0.05) of the variation in aflatoxin contamination, which varied from 0 to c. 800 mu g/kg in 17 large-scale sowings in tropical and four sowings in sub-tropical environments carried out in Australia between 13 November and 16 December 2007. ARI also explained 0.96 (P <= 0.01) of the variation in the proportion of aflatoxin-contaminated loads (>15 mu g/kg) of peanuts in the Kingaroy region of Australia during the period between the 1998/99 and 2007/08 seasons. Simulation of ARI using historical climatic data from 1890 to 2007 indicated a three-fold increase in its value since 1980 compared to the entire previous period. The increase was associated with increases in ambient temperature and decreases in rainfall. To facilitate routine monitoring of aflatoxin risk by growers in near real time, a web interface of the model was also developed. The ARI predicted using this interface for eight growers correlated significantly with the level of contamination in crops (r=095, P <= 0.01). These results suggest that ARI simulated by the model is a reliable indicator of aflatoxin contamination that can be used in aflatoxin research as well as a decision-support tool to monitor pre-harvest aflatoxin risk in peanuts.

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The semiconductivity inMTiO3 (M=Ba, Sr) in the temperature range of practical applications is greatly influenced by the electronic charge redistribution among the acceptor states, arising from the frozen cation vacancies as well as the transition metal ion impurities. The conductivity measurements and defect chemistry investigations above 800 K indicate that the predominant lattice defects areM− and oxygen vacancies. There is dominantp-type conduction at higherP O 2 values in acceptor doped materials at high temperatures. However, they are insulating solids around room temperature due to the redistribution of electrons between the neutral, singly-or doubly-ionised acceptor states. Results fromepr and resistivity measurements show that the above charge redistribution is dependent on crystal structure changes. Hence the electron or hole loss by the acceptor states is influenced by the soft modes which also accounts for the differences in electrical properties of BaTiO3 and SrTiO3. The results are also useful in explaining the positive temperature coefficient in resistance and some photo-electrochemcial properties of these solids.

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The pattern of growth and development of seed crops of stylo (Stylosanthes guyanensis) was derived from measurements made on experimental and commercial crops in north Queensland. The three cultivars Cook, Endeavour, and Schofield differed appreciably only in the timetable of their development. Each had distinct successive phases of vegetative and reproductive development culminating in total annual seed production of 700-800 kg ha-1 from a healthy closed canopy, the main recorded cause of reduced production being the disease Botrytis sp. In a healthy crop of Cook, the peak quantity of standing seed represented almost 90 per cent of the total accountable seed, and the rise to and decline from this peak proceeded at rates of the order of 3-4 per cent per day. It is deduced that, although there appears to be little potential for either increase in overall production or improvement in synchronization or retention characteristics beyond that currently attained by a closed canopy of healthy plants, there is scope for an increase in the efficiency of recovery of standing seed. Maximum recovery will be achieved through attention to choice of time of harvest, presentation of a minimum amount of extraneous vegetation to the harvester, and improvement in harvester separation.

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Rapid solidification of Ti-7.3wt.%Cu (near-eutectoid composition), Ti-36.2wt.%Ni and Ti-34.3wt.% Ni-5.8wt.%Si alloys has been carried out by electron beam melting and splat quenching on a water-cooled rotating copper disc. The product obtained was in the form of thin ribbons 60–100 μm thick. Transmission electron microscopy studies of Ti---Cu alloy splats showed that the microstructure consisted of a mixture of martensite and a lamellar eutectoid product. The formation of the intermetallic compound Ti2Cu involved a diffusionless ω transformation and spinodal clustering. In the case of Ti---Ni alloy the as-quenched microstructure is complex, consisting of α, transformed β and intermetallic phases. This could have arisen possibly as a result of local variation in cooling rates. Rapid solidification of Ti---Ni---Si alloy resulted in partial quenching of an amorphous phase. The amorphous phase was seen to be extremely hard (a Vickers hardness of about 800 HV).

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Prescribing for older patients is challenging. The prevalence of diseases increases with advancing age and causes extensive drug use. Impairments in cognitive, sensory, social and physical functioning, multimorbidity and comorbidities, as well as age-related changes in pharmacokinetics and pharmacodynamics all add to the complexity of prescribing. This study is a cross-sectional assessment of all long-term residents aged ≥ 65 years in all nursing homes in Helsinki, Finland. The residents’ health status was assessed and data on their demographic factors, health and medications were collected from their medical records in February 2003. This study assesses some essential issues in prescribing for older people: psychotropic drugs (Paper I), laxatives (Paper II), vitamin D and calcium supplements (Paper III), potentially inappropriate drugs for older adults (PIDs) and drug-drug interactions (DDIs)(Paper IV), as well as prescribing in public and private nursing homes. A resident was classified as a medication user if his or her medication record indicated a regular sequence for its dosage. Others were classified as non-users. Mini Nutritional Assessment (MNA) was used to assess residents’ nutritional status, Beers 2003 criteria to assess the use of PIDs, and the Swedish, Finnish, INteraction X-referencing database (SFINX) to evaluate their exposure to DDIs. Of all nursing home residents in Helsinki, 82% (n=1987) participated in studies I, II, and IV and 87% (n=2114) participated in the study III. The residents’ mean age was 84 years, 81% were female, and 70% were diagnosed with dementia. The mean number of drugs was 7.9 per resident; 40% of the residents used ≥ 9 drugs per day, and were thus exposed to polypharmacy. Eighty percent of the residents received psychotropics; 43% received antipsychotics, and 45% used antidepressants. Anxiolytics were prescribed to 26%, and hypnotics to 28% of the residents. Of those residents diagnosed with dementia, 11% received antidementia drugs. Fifty five percent of the residents used laxatives regularly. In multivariate analysis, those factors associated with regular laxative use were advanced age, immobility, poor nutritional status, chewing problems, Parkinson’s disease, and a high number of drugs. Eating snacks between meals was associated with lower risk for laxative use. Of all participants, 33% received vitamin D supplementation, 28% received calcium supplementation, and 20% received both vitamin D and calcium. The dosage of vitamin D was rather low: 21% received vitamin D 400 IU (10 µg) or more, and only 4% received 800 IU (20 µg) or more. In multivariate analysis, residents who received vitamin D supplementation enjoyed better nutritional status, ate snacks between meals, suffered no constipation, and received regular weight monitoring. Those residents receiving PIDs (34% of all residents) more often used psychotropic medication and were more often exposed to polypharmacy than residents receiving no PIDs. Residents receiving PIDs were less often diagnosed with dementia than were residents receiving no PIDs. The three most prevalent PIDs were short-acting benzodiazepine in greater dosages than recommended, hydroxyzine, and nitrofurantoin. These three drugs accounted for nearly 77% of all PID use. Of all residents, less than 5% were susceptible to a clinically significant DDI. The most common DDIs were related to the use of potassium-sparing diuretics, carbamazepine, and codeine. Residents exposed to potential DDIs were younger, had more often suffered a previous stroke, more often used psychotropics, and were more often exposed to PIDs and polypharmacy than were residents not exposed to DDIs. Residents in private nursing homes were less often exposed to polypharmacy than were residents in public nursing homes. Long-term residents in nursing homes in Helsinki use, on average, nearly eight drugs daily. The use of psychotropic drugs in our study was notably more common than in international studies. The prevalence of laxatives equaled other prior international studies. Regardless of the known benefit and recommendation of vitamin D supplementation for elderly residing mostly indoors, the proportion of nursing home residents receiving vitamin D and calcium was surprisingly low. The use of PIDs was common among nursing home residents. PIDs increased the likelihood of DDIs. However, DDIs did not seem a major concern among the nursing home population. Monitoring PIDs and potential drug interactions could improve the quality of prescribing.

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Hereditary nonpolyposis colorectal cancer (HNPCC) and familial adenomatous polyposis (FAP) are characterized by a high risk and early onset of colorectal cancer (CRC). HNPCC is due to a germline mutation in one of the following MMR genes: MLH1, MSH2, MSH6 and PMS2. A majority of FAP and attenuated FAP (AFAP) cases are due to germline mutations of APC, causing the development of multiple colorectal polyps. To date, over 450 MMR gene mutations and over 800 APC mutations have been identified. Most of these mutations lead to a truncated protein, easily detected by conventional mutation detection methods. However, in about 30% of HNPCC and FAP, and about 90% of AFAP families, mutations remain unknown. We aimed to clarify the genetic basis and genotype-phenotype correlation of mutation negative HNPCC and FAP/AFAP families by advanced mutation detection methods designed to detect large genomic rearrangements, mRNA and protein expression alterations, promoter mutations, phenotype linked haplotypes, and tumoral loss of heterozygosity. We also aimed to estimate the frequency of HNPCC in Uruguayan CRC patients. Our expression based analysis of mutation negative HNPCC divided these families into two categories: 1) 42% of families linked to the MMR genes with a phenotype resembling that of mutation positive, and 2) 58% of families likely to be associated with other susceptibility genes. Unbalanced mRNA expression of MLH1 was observed in two families. Further studies revealed that a MLH1 nonsense mutation, R100X was associated with aberrant splicing of exons not related to the mutation and an MLH1 deletion (AGAA) at nucleotide 210 was associated with multiple exon skipping, without an overall increase in the frequency of splice events. APC mutation negative FAP/AFAP families were divided into four groups according to the genetic basis of their predisposition. Four (14%) families displayed a constitutional deletion of APC with profuse polyposis, early age of onset and frequent extracolonic manifestations. Aberrant mRNA expression of one allele was observed in seven (24%) families with later onset and less frequent extracolonic manifestations. In 15 (52%) families the involvement of APC could neither be confirmed nor excluded. In three (10%) of the families a germline mutation was detected in genes other than APC: AXIN2 in one family, and MYH in two families. The families with undefined genetic basis and especially those with AXIN2 or MYH mutations frequently displayed AFAP or atypical polyposis. Of the Uruguayan CRC patients, 2.6% (12/461) fulfilled the diagnostic criteria for HNPCC and 5.6% (26/461) were associated with increased risk of cancer. Unexpectedly low frequency of molecularly defined HNPCC cases may suggest a different genetic profile in the Uruguayan population and the involvement of novel susceptibility genes. Accurate genetic and clinical characterization of families with hereditary colorectal cancers, and the definition of the genetic basis of "mutation negative" families in particular, facilitate proper clinical management of such families.

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To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05) higher % of birds in the range (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly more using the shelterbelts in the afternoon than in the morning. Approximately 17 times more birds used the forage areas compared to the control area in the corresponding range. There were 8 times more birds using a hay bale enriched area compared to the area with no hay bales. The use of forage sources (including hay bales) were the most successful method on-farm to attract birds into the range followed by shelterbelts and artificial shade. Free range egg farmers are encouraged to provide pasture, shaded areas and shelterbelts to attract birds into the free range.

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Development of new agricultural industries in northern Australia is seen as a way to provide food security in the face of reduced water availability in existing regions in the south. This report aims to identify some of the possible economic consequences of developing a rice industry in the Burdekin region, while there is a reduction of output in the Riverina. Annual rice production in the Riverina peaked at 1.7 M tonnes, but the long-term outlook, given climate change impacts on that region and government water buy-backs, is more likely to be less than 800,000 tonnes. Growers are highly efficient water users by international standards, but the ability to offset an anticipated reduction in water availability through further efficiency gains is limited. In recent years growers in the Riverina have diversified their farms to a greater extent and secondary production systems include beef, sheep and wheat. Production in north Queensland is in its infancy, but a potentially suitable farming system has been developed by including rice within the sugarcane system without competition and in fact contributing to the production of sugar by increasing yields and controlling weeds. The economic outcomes are estimated a large scale, dynamic, computable general equilibrium (CGE) model of the world economy (Tasman Global), scaled down to regional level. CGE models mimic the workings of the economy through a system of interdependent behavioural and accounting equations which are linked to an input-output database. When an economic shock or change is applied to a model, each of the markets adjusts according to the set of behavioural parameters which are underpinned by economic theory. In this study the model is driven by reducing production in the Riverina in accordance with relationships found between water availability and the production of rice and replacement by other crops and by increasing ride production in the Burdekin. Three scenarios were considered: • Scenario 1: Rice is grown using the fallow period between the last ratoon crop of sugarcane and the new planting. In this scenario there is no competition between rice and sugarcane • Scenario 2: Rice displaces sugarcane production • Scenario 3: Rice is grown on additional land and does not compete with sugarcane. Two time periods were used, 2030 and 2070, which are the conventional time points to consider climate change impacts. Under scenario 1, real economic output declines in the Riverina by $45 million in 2030 and by $139 million in 2070. This is only partially offset by the increased real economic output in the Burdekin of $35 million and $131 million respectively.

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Single crystals of K, Rb and Cs perchlorates have been grown by the counter diffusion of the respective ions and CIO4 through the gel medium. Studies on nucleation, growth kinetics, morphological aspects and purity are discussed in this paper. The dielectric constant, ~b, as well as loss measured along the longest axis, exhibits an anomaly at the transition temperature, Tt, in all the three crystals. It is found that the peak values of Tt are approximately 800, 100 and 53 in K, Rb and Cs perchlorates, respectively. The dielectric anomaly and the large value of c b in the cubic phase are discussed in terms of the degree of disorder of the CIO~ group and the possible contribution from defects.

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Adsorption has been considered as an efficient method for the treatment of dye effluents, but properdisposal of the spent adsorbents is still a challenge. This work attempts to provide a facile methodto reutilize the spent Mg/Al layered double hydroxide (Mg/Al-LDH) after the adsorption of orange II(OII). Herein, the spent hybrid was carbonized under the protection of nitrogen, and then washedwith acid to obtain porous carbon materials. Thermogravimetric analysis results suggested that thecarbonization could be well achieved above 600◦C, as mass loss of the spent hybrid gradually stabilized. Therefore, the carbonization process was carried out at 600, 800, and 1000 ◦C, respectively. Scanning electron microscope showed that the obtained carbon materials possessed a crooked flaky morphology. Nitrogen adsorption–desorption results showed that the carbon materials had large BET surface area and pore volume, e.g., 1426 m2/g and 1.67 cm3/g for the sample carbonized at 800 ◦C. Moreover, the pore structure and surface chemistry compositions were tunable, as they were sensitive to the temperature. Toluene adsorption results demonstrated that the carbon materials had high efficiency in toluene removal. This work provided a facile approach for synthesizing porous carbon materials using spent Mg/Al-LDH.

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The i.r. spectra of some Ln2BO4 and LnSrBO4 compounds (Ln = La, Pr, Nd, Sm or Gd;B = Fe, Al, Co or Cu) with K2NiF4 or related structures have been studied in the range 800-300 cm−1. The BO6 octahedra in compounds with K2NiF4 structure are elongated. The assignment of the bands in terms of internal modes of sheets of bridged BO6 octahedra or square-planar BO4 sheets has been considered. The observed spectra are correlated with those of solid solutions of these oxides and of LnBO3 perovskites. Unusually high stretching frequencies found in some of the oxides are discussed in terms of the short B---O bonds in the basal plane and the Ln---O bonds along the c axis.

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The i.r. spectra of some Ln2BO4 and LnSrBO4 compounds (Ln = La, Pr, Nd, Sm or Gd;B = Fe, Al, Co or Cu) with K2NiF4 or related structures have been studied in the range 800-300 cm−1. The BO6 octahedra in compounds with K2NiF4 structure are elongated. The assignment of the bands in terms of internal modes of sheets of bridged BO6 octahedra or square-planar BO4 sheets has been considered. The observed spectra are correlated with those of solid solutions of these oxides and of LnBO3 perovskites. Unusually high stretching frequencies found in some of the oxides are discussed in terms of the short B---O bonds in the basal plane and the Ln---O bonds along the c axis.

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The objective of the present study was to establish a valid transformation method of Haemophilus parasuis, the causative agent of Glasser's disease in pigs, using a novel H. parasuis-Escherichia coli shuttle vector. A 4.2 kb endogenous plasmid pYC93 was extracted from an H. parasuis field isolate and completely sequenced. Analysis of pYC93 revealed a region approximately 800 bp showing high homology with the defined replication origin oriV of pLS88, a native plasmid identified in Haemophilus ducreyi. Based on the origin region of pYC93, E. coli cloning vector pBluescript SK(+) and the Tn903 derived kanamycin cassette, a shuttle vector pSHK4 was constructed by overlapping PCR strategy. When electroporation of the 15 H. parasuis serovar reference strains and one clinical isolate SH0165 with pSHK4 was performed, only one of these strains yielded transformants with an efficiency of 8.5 x 10(2) CFUhlg of DNA. Transformation efficiency was notably increased (1.3 x 10(5) CFU/mu g of DNA) with vector DNA reisolated from the homologous transformants. This demonstrated that restriction-modification systems were involved in the barrier to transformation of H. parasuis. By utilizing an in vitro DNA modification method with cell-free extracts of the host H. parasuis strains, 15 out of 16 strains were transformable. The novel shuttle vector pSHK4 and the established electrotransformation method constitute useful tools for the genetic manipulation of H. parasuis to gain a better understanding of the pathogen. (C) 2011 Elsevier B.V. All rights reserved.

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Hydrogen cyanide (HCN) is a toxic chemical that can potentially cause mild to severe reactions in animals when grazing forage sorghum. Developing technologies to monitor the level of HCN in the growing crop would benefit graziers, so that they can move cattle into paddocks with acceptable levels of HCN. In this study, we developed near-infrared spectroscopy (MRS) calibrations to estimate HCN in forage sorghum and hay. The full spectral NIRS range (400-2498 nm) was used as well as specific spectral ranges within the full spectral range, i.e., visible (400-750 nm), shortwave (800-1100 nm) and near-infrared (NIR) (1100-2498 nm). Using the full spectrum approach and partial least-squares (PLS), the calibration produced a coefficient of determination (R-2) = 0.838 and standard error of cross-validation (SECV) = 0.040%, while the validation set had a R-2 = 0.824 with a low standard error of prediction (SEP = 0.047%). When using a multiple linear regression (MLR) approach, the best model (NIR spectra) produced a R-2 = 0.847 and standard error of calibration (SEC) = 0.050% and a R-2 = 0.829 and SEP = 0.057% for the validation set. The MLR models built from these spectral regions all used nine wavelengths. Two specific wavelengths 2034 and 2458 nm were of interest, with the former associated with C=O carbonyl stretch and the latter associated with C-N-C stretching. The most accurate PLS and MLR models produced a ratio of standard error of prediction to standard deviation of 3.4 and 3.0, respectively, suggesting that the calibrations could be used for screening breeding material. The results indicated that it should be feasible to develop calibrations using PLS or MLR models for a number of users, including breeding programs to screen for genotypes with low HCN, as well as graziers to monitor crop status to help with grazing efficiency.