891 resultados para Retained austenite


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Organic photovoltaic devices with either bulk heterojunction (BHJ) or nanoparticulate (NP) active layers have been prepared from a 1:2 blend of (poly{3,6-dithiophene-2-yl-2,5-di(2-octyldodecyl)-pyrrolo[3,4-c]pyrrole-1, 4-dione-alt-naphthalene}) (PDPP-TNT) and the fullerene acceptor, ([6,6]-phenyl C71-butyric acid methyl ester) (PC70BM). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) have been used to investigate the morphology of the active layers of the two approaches. Mild thermal treatment of the NP film is required to promote initial joining of the NPs in order for the devices to function, however the NP structure is retained. Consequently, whereas gross phase segregation of the active layer occurs in the BHJ device spin cast from chloroform, the nanoparticulate approach retains control of the material domain sizes on the length scale of exciton diffusion in the materials. As a result, NP devices are found to generate more than twice the current density of BHJ devices and have a substantially greater overall efficiency. The use of aqueous nanoparticulate dispersions offers a promising approach to control the donor acceptor morphology on the nanoscale with the benefit of environmentally- friendly, solution-based fabrication. © 2014 the Owner Societies.

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The primary motivation for the vehicle replacement schemes that were implemented in many countries was to encourage the purchase of new cars. The basic assumption of these schemes was that these acquisitions would benefit both the economy and the environment as older and less fuel-efficient cars were scrapped and replaced with more fuel-efficient models. In this article, we present a new environmental impact assessment method for assessing the effectiveness of scrappage schemes for reducing CO2 emissions taking into account the rebound effect, driving behavior for older versus new cars and entire lifecycle emissions for during the manufacturing processes of new cars. The assessment of the Japanese scrappage scheme shows that CO2 emissions would only decrease if users of the scheme retained their new gasoline passenger vehicles for at least 4.7 years. When vehicle replacements were restricted to hybrid cars, the reduction in CO2 achieved by the scheme would be 6-8.5 times higher than the emissions resulting from a scheme involving standard, gasoline passenger vehicles. Cost-benefit analysis, based on the emission reduction potential, showed that the scheme was very costly. Sensitivity analysis showed that the Japanese government failed to determine the optimum, or target, car age for scrapping old cars in the scheme. Specifically, scrapping cars aged 13 years and over did not maximize the environmental benefits of the scheme. Consequently, modifying this policy to include a reduction in new car subsidies, focused funding for fuel-efficient cars, and modifying the target car age, would increase environmental benefits. © 2013 Elsevier Ltd.

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A. Background and context 1. Education, particularly basic education (grades1-9), has been considered critical to promoting national economic growth and social well being1. Three factors that con-tribute to the above are: (i) Education increases human capital inherent in a labor force and thus increases productivity. It also increases capacity for working with others and builds community consensus to support national development. (ii) Education can in-crease the innovative capacity of a community to support social and economic growth—use of new technologies, products and services to promote growth and wellbeing. (iii) Education can facilitate knowledge transfer needed to understand the social and eco-nomic innovations and new processes, practices and values. Cognizant of the above benefits of education, the Millennium Development Goals (MDG) and the Education for All (EFA) declarations advocating universal basic education were formulated and ratified by UN member countries. 2. Achieving universal primary education (grade 6) may not be sufficient to maxim-ize the above noted socio-economic and cultural benefits. There is general consensus that basic literacy and numeracy up to grade 9 are essential foundational blocks for any good education system to support national development. Basic Education provides an educational achievement threshold that ensures the learning is retained. To achieve this, the donor partner led interventions and the UN declarations such as the MDG goals have sought universal access to basic education (grades 1-9). As many countries progress towards achieving the universal access targets, recent research evidence suggests that we need more than just access to basic education to impact on the na-tional development. Measuring basic education completion cycle, gross enrolment rate (GER) and participation rate etc., has to now include a focus on quality and relevance of the education2. 3. While the above research finding is generally accepted by the Government of In-donesia (GoI), unlike many other developing countries, Indonesia is geographically and linguistically complex and has the fourth largest education sector in the world. It has over 3000 islands, 17,000 ethnic groups and it takes as long as 7 hours to travel from east to west of the country and has multiple time differences. The education system has six years of primary education (grades 1-6), 3 years of junior secondary education (grades 7-9) and three years of senior secondary education (grades 10-12). Therefore, applying the findings of the above cited research in a country like Indonesia is a chal-lenge. Nevertheless, since the adoption of the National Education Law (2003)3 the GoI has made significant progress in improving access to and quality of basic education (grades 1-9). The 2011/12 national education statistics show the primary education (grades 1-6) completion rate was 99.3%, the net enrolment rate (NER) was 95.4% and the GER was 115.4%. This is a significant achievement considering the complexities faced within Indonesia. This increase in the primary education sub-sector, however, has not flowed onto the Junior Secondary School (JSS) education. The transition from pri-mary to JSS is still short of the GoI targets. In 2012, there were 146,826 primary schools feeding into 33,668 junior secondary schools. The transition rate from primary to secondary in 2011/12 was 78%. When considering district or sub-district level data the transition in poor districts could be less than the aggregated national rate. Poverty and lack of parents’ education, confounded by opportunity cost, are major obstacles to transitioning to JSS4. 4. Table 1 presents a summary of GoI initiatives to accelerate the transition to JSS. GoI, with assistance from the donor community, has built 2465 new regular JSS, mak-ing the total number of regular JSS 33,668. In addition, 57,825 new classrooms have been added to existing regular JSS. Also, in rural and remote areas 4136 Satu-Atap5 (SATAP) schools were built to increase access to JSS. These SATAP schools are the focus of this study as they provide education opportunities to the most marginalized, ru-ral, remote children who otherwise would not have access to JSS and consequently not complete basic education.

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Study Design Delphi panel and cohort study. Objective To develop and refine a condition-specific, patient-reported outcome measure, the Ankle Fracture Outcome of Rehabilitation Measure (A-FORM), and to examine its psychometric properties, including factor structure, reliability, and validity, by assessing item fit with the Rasch model. Background To our knowledge, there is no patient-reported outcome measure specific to ankle fracture with a robust content foundation. Methods A 2-stage research design was implemented. First, a Delphi panel that included patients and health professionals developed the items and refined the item wording. Second, a cohort study (n = 45) with 2 assessment points was conducted to permit preliminary maximum-likelihood exploratory factor analysis and Rasch analysis. Results The Delphi panel reached consensus on 53 potential items that were carried forward to the cohort phase. From the 2 time points, 81 questionnaires were completed and analyzed; 38 potential items were eliminated on account of greater than 10% missing data, factor loadings, and uniqueness. The 15 unidimensional items retained in the scale demonstrated appropriate person and item reliability after (and before) removal of 1 item (anxious about footwear) that had a higher-than-ideal outfit statistic (1.75). The “anxious about footwear” item was retained in the instrument, but only the 14 items with acceptable infit and outfit statistics (range, 0.5–1.5) were included in the summary score. Conclusion This investigation developed and refined the A-FORM (Version 1.0). The A-FORM items demonstrated favorable psychometric properties and are suitable for conversion to a single summary score. Further studies utilizing the A-FORM instrument are warranted. J Orthop Sports Phys Ther 2014;44(7):488–499. Epub 22 May 2014. doi:10.2519/jospt.2014.4980

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Uropathogenic Escherichia coli (UPEC) is responsible for the majority of urinary tract infections (UTI). To cause a UTI, UPEC must adhere to the epithelial cells of the urinary tract and overcome the shear flow forces of urine. This function is mediated primarily by fimbrial adhesins, which mediate specific attachment to host cell receptors. Another group of adhesins that contributes to UPEC-mediated UTI is autotransporter (AT) proteins. AT proteins possess a range of virulence properties, such as adherence, aggregation, invasion, and biofilm formation. One recently characterized AT protein of UPEC is UpaH, a large adhesin-involved-in-diffuse-adherence (AIDA-I)-type AT protein that contributes to biofilm formation and bladder colonization. In this study we characterized a series of naturally occurring variants of UpaH. We demonstrate that extensive sequence variation exists within the passenger-encoding domain of UpaH variants from different UPEC strains. This sequence variation is associated with functional heterogeneity with respect to the ability of UpaH to mediate biofilm formation. In contrast, all of the UpaH variants examined retained a conserved ability to mediate binding to extracellular matrix (ECM) proteins. Bioinformatic analysis of the UpaH passenger domain identified a conserved region (UpaHCR) and a hydrophobic region (UpaHHR). Deletion of these domains reduced biofilm formation but not the binding to ECM proteins. Despite variation in the upaH sequence, the transcription of upaH was repressed by a conserved mechanism involving the global regulator H-NS, and mutation of the hns gene relieved this repression. Overall, our findings shed new light on the regulation and functions of the UpaH AT protein.

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Acid sulfate soils (ASS) is a stress factor that is responsible for the failure of some mangrove restoration projects, including abandoned aquaculture ponds converted from mangrove ecosystems. Through experimental and field studies, this research provides a better understanding of the biogeochemistry of ASS disturbance and the response of mangrove seedlings (Rhizophoraceae) under high metal levels and acidic conditions. This study found that mangrove restorations under ASS disturbance can work but with lower numbers of survived seedlings. To prevent toxicity under high levels of metal, seedlings retained metals in their roots and sparingly distributed them into aerial parts with low mobility. The presence of high levels of potential acidity parameters would allow pyrite to oxidise, thus increasing metal levels and acidity, which in turn affected the survival and growth of the seedlings.

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The importance of clean drinking water in any community is absolutely vital if we as the consumers are to sustain a life of health and wellbeing. Suspended particles in surface waters not only provide the means to transport micro-organisms which can cause serious infections and diseases, they can also affect the performance capacity of a water treatment plant. In such situations pre-treatment ahead of the main plant is recommended. Previous research carried out using non-woven synthetic as a pre-filter materials for protecting slow sand filters from high turbidity showed that filter run times can be extended by several times and filters can be regenerated by simply removing and washing of the fabric ( Mbwette and Graham, 1987 and Mbwette, 1991). Geosynthetic materials have been extensively used for soil retention and dewatering in geotechnical applications and little research exists for the application of turbidity reduction in water treatment. With the development of new materials in geosynthetics today, it was hypothesized that the turbidity removal efficiency can be improved further by selecting appropriate materials. Two different geosynthetic materials (75 micron) tested at a filtration rate of 0.7 m/h yielded 30-45% reduction in turbidity with relatively minor head loss. It was found that the non-woven geotextile Propex 1701 retained the highest performance in both filtration efficiency and head loss across the varying turbidity ranges in comparison to other geotextiles tested. With 5 layers of the Propex 1701 an average percent reduction of approximately 67% was achieved with a head loss average of 4mm over the two and half hour testing period. Using the data collected for the Propex 1701 a mathematical model was developed for predicting the expected percent reduction given the ability to control the cost and as a result the number of layers to be used in a given filtration scenario.

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A vital element to improve outcomes for disadvantaged students is outstanding teachers. A reality, however, is that teacher graduates in the top quartile of academic scores are far less likely to accept positions in tough urban, regional, rural and remote schools. Further, because high poverty schools can be challenging environments, these teachers are retained for much shorter periods of time. In response to this challenge, the National Exceptional Teachers for Disadvantaged Schools program (NETDS) creates a pathway for the highest quality pre-service teachers to be fully prepared, professionally and personally, for roles within high poverty schools. The program identifies the highest-achieving mainstream preservice teachers in university programs across the country and offers them a specialised curriculum and supported practicum experience in a network of disadvantaged partner schools. By working closely with government, philanthropy and partner schools, the program also works to channel these exceptional pre-service teachers into employment in schools where they will have the greatest impact. Its initial results have been exceptional: over 90% of graduates are now employed as teachers in high poverty schools. This paper will discuss their research on how they are working to build the infrastructure and capacity for research on innovations that prepare teachers for 21st century schools in the Australian context.

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Kiwi (Apteryx spp.) have a visual system unlike that of other nocturnal birds, and have specializations to their auditory, olfactory and tactile systems. Eye size, binocular visual fields and visual brain centers in kiwi are proportionally the smallest yet recorded among birds. Given the many unique features of the kiwi visual system, we examined the laminar organization of the kiwi retina to determine if they evolved increased light sensitivity with a shift to a nocturnal niche or if they retained features of their diurnal ancestor. The laminar organization of the kiwi retina was consistent with an ability to detect low light levels similar to that of other nocturnal species. In particular, the retina appeared to have a high proportion of rod photoreceptors compared to diurnal species, as evidenced by a thick outer nuclear layer, and also numerous thin photoreceptor segments intercalated among the conical shaped cone photoreceptor inner segments. Therefore, the retinal structure of kiwi was consistent with increased light sensitivity, although other features of the visual system, such as eye size, suggest a reduced reliance on vision. The unique combination of a nocturnal retina and smaller than expected eye size, binocular visual fields and brain regions make the kiwi visual system unlike that of any bird examined to date. Whether these features of their visual system are an evolutionary design that meets their specific visual needs or are a remnant of a kiwi ancestor that relied more heavily on vision is yet to be determined.

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Background Understanding the progression of prostate cancer to androgen-independence/castrate resistance and development of preclinical testing models are important for developing new prostate cancer therapies. This report describes studies performed 30 years ago, which demonstrate utility and shortfalls of xenografting to preclinical modeling. Methods We subcutaneously implanted male nude mice with small prostate cancer fragments from transurethral resection of the prostate (TURP) from 29 patients. Successful xenografts were passaged into new host mice. They were characterized using histology, immunohistochemistry for marker expression, flow cytometry for ploidy status, and in some cases by electron microscopy and response to testosterone. Two xenografts were karyotyped by G-banding. Results Tissues from 3/29 donors (10%) gave rise to xenografts that were successfully serially passaged in vivo. Two, (UCRU-PR-1, which subsequently was replaced by a mouse fibrosarcoma, and UCRU-PR-2, which combined epithelial and neuroendocrine features) have been described. UCRU-PR-4 line was a poorly differentiated prostatic adenocarcinoma derived from a patient who had undergone estrogen therapy and bilateral castration after his cancer relapsed. Histologically, this comprised diffusely infiltrating small acinar cell carcinoma with more solid aggregates of poorly differentiated adenocarcinoma. The xenografted line showed histology consistent with a poorly differentiated adenocarcinoma and stained positively for prostatic acid phosphatase (PAcP), epithelial membrane antigen (EMA) and the cytokeratin cocktail, CAM5.2, with weak staining for prostate specific antigen (PSA). The line failed to grow in female nude mice. Castration of three male nude mice after xenograft establishment resulted in cessation of growth in one, growth regression in another and transient growth in another, suggesting that some cells had retained androgen sensitivity. The karyotype (from passage 1) was 43–46, XY, dic(1;12)(p11;p11), der(3)t(3:?5)(q13;q13), -5, inv(7)(p15q35) x2, +add(7)(p13), add(8)(p22), add(11)(p14), add(13)(p11), add(20)(p12), -22, +r4[cp8]. Conclusions Xenografts provide a clinically relevant model of prostate cancer, although establishing serially transplantable prostate cancer patient derived xenografts is challenging and requires rigorous characterization and high quality starting material. Xenografting from advanced prostate cancer is more likely to succeed, as xenografting from well differentiated, localized disease has not been achieved in our experience. Strong translational correlations can be demonstrated between the clinical disease state and the xenograft model

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The current study sought to explore whether the subcutaneous administration of lymph-targeted dendrimers, conjugated with a model chemotherapeutic (methotrexate, MTX), was able to enhance anticancer activity against lymph node metastases. The lymphatic pharmacokinetics and antitumour activity of PEGylated polylysine dendrimers conjugated to MTX [D-MTX(OH)] via a tumour-labile hexapeptide linker was examined in rats and compared to a similar system where MTX was α-carboxyl O-tert-butylated [D-MTX(OtBu)]. The latter has previously been shown to exhibit longer plasma circulation times. D-MTX(OtBu) was well absorbed from the subcutaneous injection site via the lymph, and 3 to 4%/g of the dose was retained by sentinel lymph nodes. In contrast, D-MTX(OH) showed limited absorption from the subcutaneous injection site, but absorption was almost exclusively via the lymph. The retention of D-MTX(OH) by sentinel lymph nodes was also significantly elevated (approximately 30% dose/g). MTX alone was not absorbed into the lymph. All dendrimers displayed lower lymph node targeting after intravenous administration. Despite significant differences in the lymph node retention of D-MTX(OH) and D-MTX(OtBu) after subcutaneous and intravenous administration, the growth of lymph node metastases was similarly inhibited. In contrast, the administration of MTX alone did not significantly reduce lymph node tumour growth. Subcutaneous administration of drug-conjugated dendrimers therefore provides an opportunity to improve drug deposition in downstream tumour-burdened lymph nodes. In this case, however, increased lymph node biodistribution did not correlate well with antitumour activity, possibly suggesting constrained drug release at the site of action.

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High-throughput plasmid DNA (pDNA) manufacture is obstructed predominantly by the performance of conventional stationary phases. For this reason, the search for new materials for fast chromatographic separation of pDNA is ongoing. A poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (GMA-EGDMA) monolithic material was synthesised via a thermal-free radical reaction, functionalised with different amino groups from urea, 2-chloro-N,N-diethylethylamine hydrochloride (DEAE-Cl) and ammonia in order to investigate their plasmid adsorption capacities. Physical characterisation of the monolithic polymer showed a macroporous polymer having a unimodal pore size distribution pivoted at 600 nm. Chromatographic characterisation of the functionalised polymers using pUC19 plasmid isolated from E. coli DH5α-pUC19 showed a maximum plasmid adsorption capacity of 18.73 mg pDNA/mL with a dissociation constant (KD) of 0.11 mg/mL for GMA-EGDMA/DEAE-Cl polymer. Studies on ligand leaching and degradation demonstrated the stability of GMA-EGDMA/DEAE-Cl after the functionalised polymers were contacted with 1.0 M NaOH, which is a model reagent for most 'cleaning in place' (CIP) systems. However, it is the economic advantage of an adsorbent material that makes it so attractive for commercial purification purposes. Economic evaluation of the performance of the functionalised polymers on the grounds of polymer cost (PC)/mg pDNA retained endorsed the suitability of GMA-EGDMA/DEAE-Cl polymer.

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Emotionally significant memories, especially those induced in conjunction with physical and mental trauma, are frequently retained for an individual’s lifetime. How these memories are organized and encoded within neural networks is a fundamental question. The lateral amygdala (LA) is a key nucleus for acquisition and maintenance of associative emotional memories. We used Pavlovian fear conditioning to study how ‘weaker’ and ‘stronger’ memories are encoded in neural networks of the LA. In Pavlovian fear conditioning a neutral stimulus, in this case a tone, is temporally paired with an aversive unconditioned stimulus (US), such as a foot shock. The previously neutral stimulus becomes a conditioned stimulus (CS) capable of eliciting defensive responses. We used time spent freezing when the CS is presented in a neutral context as a dependent variable measure of memory ‘strength’.

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The International Journal of the First Year in Higher Education (Int J FYHE) began in 2010 with a specific FYHE focus and has published two issues per year with one issue linked to The International First Year in Higher Education Conference (FYHE Conference). This issue—Volume 6, Issue 1—is the last under this title. In 2015 the Journal will align to a new conference that has a broader focus on Students, Transitions, Achievement, Retention and Success (STARS). At this significant point and before we move on to the new journal, the journal team felt it was appropriate that the Feature in this final issue of the Int J FYHE should summarise the Journal’s activity over the years from 2010 to 2014.

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Background Child sexual abuse is a significant global problem in both magnitude and sequelae. The most widely used primary prevention strategy has been the provision of school-based education programmes. Although programmes have been taught in schools since the 1980s, their effectiveness requires ongoing scrutiny. Objectives To systematically assess evidence of the effectiveness of school-based education programmes for the prevention of child sexual abuse. Specifically, to assess whether: programmes are effective in improving students’ protective behaviours and knowledge about sexual abuse prevention; behaviours and skills are retained over time; and participation results in disclosures of sexual abuse, produces harms, or both. Search methods In September 2014, we searched CENTRAL, OvidMEDLINE, EMBASE and 11 other databases.We also searched two trials registers and screened the reference lists of previous reviews for additional trials. Selection criteria We selected randomised controlled trials (RCTs), cluster-RCTs, and quasi-RCTs of school-based education interventions for the prevention of child sexual abuse compared with another intervention or no intervention. Data collection and analysis Two review authors independently assessed the eligibility of trials for inclusion, extracted data, and assessed risk of bias.We summarised data for six outcomes: protective behaviours; knowledge of sexual abuse or sexual abuse prevention concepts; retention of protective behaviours over time; retention of knowledge over time; harm; and disclosures of sexual abuse. School-