947 resultados para Large type books


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CD95 (Fas/Apo-1)-mediated apoptosis was shown to occur through two distinct pathways. One involves a direct activation of caspase-3 by large amounts of caspase-8 generated at the DISC (Type I cells). The other is related to the cleavage of Bid by low concentration of caspase-8, leading to the release of cytochrome c from mitochondria and the activation of caspase-3 by the cytochrome c/APAF-1/caspase-9 apoptosome (Type 11 cells). It is also known that the protein synthesis inhibitor cycloheximide (CHX) sensitizes Type I cells to CD95-mediated apoptosis, but it remains contradictory whether this effect also occurs in Type II cells. Here, we show that sub-lethal doses of CHX render both Type I and Type II cells sensitive to the apoptogenic effect of anti-CD95 antibodies but not to chemotherapeutic drugs. Moreover, Bcl-2-positive Type II cells become strongly sensitive to CD95-mediated apoptosis by the addition of CHX to the cell culture. This is not the result of a restraint of the anti-apoptotic effect of Bcl-2 at the mitochondrial level since CHX-treated Type II cells still retain their resistance to chemotherapeutic drugs. Therefore, CHX treatment is granting the CD95-mediated pathway the ability to bypass the mitochondria requirement to apoptosis, much alike to what is observed in Type I cells. (c) 2007 Elsevier Inc. All rights reserved.

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We report the first U-Pb baddeleyite/zircon date for a felsic volcanic rock from the Parana Large Igneous Province in south Brazil. The new date of 134.3 +/- 0.8 Ma for a hypocrystalline Chapeco-type dacite from Ourinhos (northern Parana basin) is an important regional time marker for the onset of flood basalt volcanism in the northern and western portion of the province. The dated dacite was erupted onto basement rocks and is overlain by a high-Ti basalt sequence, interpreted to be correlative with Pitanga basalts elsewhere. This new U-Pb date for the Ourinhos dacite is consistent with the local stratigraphy being slightly older than the few reliable step-heating (40)Ar/(39)Ar dates currently available for overlying high-Ti basalts (133.6-131.5 Ma). This indicates an similar to 3 Ma time span for the building of the voluminous high-Ti lava sequence of the Parana basin. On the other hand, it overlaps the (40)Ar/(39)Ar dates (134.8-134.1 Ma) available for the stratigraphically older low-Ti basalt (Gramado + Esmeralda types) and dacite-rhyolite (Palmas type) sequences from South Brazil, which is consistent with the short-lived character of this volcanism and its rapid succession by the high-Ti sequence. (C) 2010 Elsevier B.V. All rights reserved.

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Xylella fastidiosa is the etiologic agent of a wide range of plant diseases, including citrus variegated chlorosis (CVC), a major threat to citrus industry. The genomes of several strains of this phytopathogen were completely sequenced, enabling large-scale functional studies. DNA microarrays representing 2,608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c were used to investigate transcript levels during growth with different iron availabilities. When treated with the iron chelator 2,2`-dipyridyl, 193 CDS were considered up-regulated and 216 were considered down-regulated. Upon incubation with 100 mu M ferric pyrophosphate, 218 and 256 CDS were considered up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription-quantitative PCR. Several CDS involved with regulatory functions, pathogenicity, and cell structure were modulated under both conditions assayed, suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to functions of pili/fimbriae. We also investigated the contribution of the ferric uptake regulator Fur to the iron stimulon of X. fastidiosa. The promoter regions of the strain 9a5c genome were screened for putative Fur boxes, and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron stimulon of X fastidiosa, and they present novel evidence for iron regulation of pathogenicity determinants.

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The PilZ protein was originally identified as necessary for type IV pilus (T4P) biogenesis. Since then, a large and diverse family of bacterial PilZ homology domains have been identified, some of which have been implicated in signaling pathways that control important processes, including motility, virulence and biofilm formation. Furthermore, many PilZ homology domains, though not PilZ itself, have been shown to bind the important bacterial second messenger bis(3`-> 5`)cyclic diGMP (c-diGMP). The crystal structures of the PilZ orthologs from Xanthomonas axonopodis pv Citri (PilZ(XAC1133), this work) and from Xanthomonas campestris pv campestris (XC1028) present significant structural differences to other PilZ homologs that explain its failure to bind c-diGMP. NMR analysis of PilZ(XAC1133) shows that these structural differences are maintained in solution. In spite of their emerging importance in bacterial signaling, the means by which NZ proteins regulate specific processes is not clear. In this study, we show that PilZ(XAC1133) binds to PilB, an ATPase required for TV polymerization, and to the EAL domain of FiMX(XAC2398), which regulates TV biogenesis and localization in other bacterial species. These interactions were confirmed in NMR, two-hybrid and far-Western blot assays and are the first interactions observed between any PilZ domain and a target protein. While we were unable to detect phosphodiesterase activity for FimXX(AC2398) in vitro, we show that it binds c-diGMP both in the presence and in the absence of PilZ(XAC1133). Site-directed mutagenesis studies for conserved and exposed residues suggest that PilZ(XAC1133) interactions with FimX(XAC2398) and PilB(XAC3239) are mediated through a hydrophobic surface and an unstructured C-terminal extension conserved only in PilZ orthologs. The FimX-PilZ-PilB interactions involve a full set of ""degenerate"" GGDEF, EAL and PilZ domains and provide the first evidence of the means by which PilZ orthologs and FimX interact directly with the TP4 machinery. (C) 2009 Elsevier Ltd. All rights reserved.

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This presentation was offered as part of the CUNY Library Assessment Conference, Reinventing Libraries: Reinventing Assessment, held at the City University of New York in June 2014.

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This report describes a method how to perform measurements on boilers and stoves and how to identify parameters from the measurements for the boiler/stove-model TRNSYS Type 210. The model can be used for detailed annual system simulations using TRNSYS. Experience from measurements on three different pellet stoves and four boilers were used to develop this methodology. Recommendations for the set up of measurements are given and the re-quired combustion theory for the data evaluation and data preparation are given. The data evalua-tion showed that the uncertainties are quite large for the measured flue gas flow rate and for boilers and stoves with high fraction of energy going to the water jacket also the calculated heat rate to the room may have large uncertainties. A methodology for the parameter identification process and identified parameters for two different stoves and three boilers are given. Finally the identified models are compared with measured data showing that the model generally agreed well with meas-ured data during both stationary and dynamic conditions.

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One of the main aims of this thesis is to design an optimized commercial Photovoltaic (PV) system in Barbados from several variables such as racking type, module type and inverter type based on practicality, technical performance as well as financial returns to the client. Detailed simulations are done in PVSYST and financial models are used to compare different systems and their viability. Once the preeminent system is determined from a financial and performance perspective a detailed design is done using PVSYST and AutoCAD to design the most optimal PV system for the customer. In doing so, suitable engineering drawings are generated which are detailed enough for construction of the system. Detailed cost with quotes from relevant manufacturers, suppliers and estimators become instrumental in determining Balance of System Costs in addition to total project cost. The final simulated system is suggested with a PV capacity of 425kW and an inverter output of 300kW resulting in an array oversizing of 1.42. The PV system has a weighted Performance Ratio of 77 %, a specific yield of 1467 kWh/kWp and a projected annual production of 624 MWh/yr. This system is estimated to offset approximately 28 % of Carlton’s electrical load annually. Over the course of 20 years the PV system is projected to produce electricity at a cost of $0.201USD/kWh which is significantly lower than the $0.35 USD/kWh paid to the utility at the time of writing this thesis. Due to the high cost of electricity on the island, an attractive Feed-In-Tariff is not necessary to warrant the installation of a commercial System which over a lifetime which produces electricity at less than 60% of the cost to the user purchasing electricity from the utility. A simple payback period of 5.4 years, a return on investment of 17 % without incentives, in addition to an estimated diversion of 6840 barrels of oil or 2168 tonnes of CO2 further provides compelling justification for the installation of a commercial Photovoltaic System not only on Carlton A-1 Supermarket, but also island wide as well as regionally where most electricity supplies are from imported fossil fuels.

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Introduction. Along the south coast of Australia, wetlands on the floodplains of lowland rivers and estuaries have been severely altered by agriculture and urbanization. Efforts to restore or rehabilitate these wetlands are hampered by insufficient knowledge of the original condition of these wetlands, or their variability in time and space. This research describes the macroinvertebrate community of wetlands on the floodplain of the Gellibrand River and estuary, which has suffered comparatively few human impacts. The aim of the research was to describe the variability of macroinvertebrate communities as a baseline for the future management of these wetlands, and to contribute to the general understanding of estuary-floodplain wetlands, thereby improving the basis for their management.

The Gellibrand River has a catchment area of approximately 1200 km2 draining the western slopes of the Otway Ranges, and entering the Southern Ocean at Princetown. From a mean annual flow of 315 000 mL, 25 000 mL are removed per annum for agricultural and domestic use (O'May & Wallace 2001), and flows are closer to natural regimes than most other Western Victorian rivers. The estuary is a bar-built, salt-wedge estuary that becomes completely blocked by the sand bar in most years, during summer and autumn. Over past decades, the estuary mouth has been opened artificially in most years. to prevent flooding of agricultural land and roads adjacent to the wetlands. At its maximum, the salt-wedge penetrates approximately 10 km upstream from the river mouth, but the estuary may also be completely fresh during high winter discharge
(Mckay 2000).

The wetlands surrounding Princetown cover 119 ha and are listed as nationally important (Environment Australia 2001). This listing regards the wetlands as an important habitat for animals at vulnerable stages of their life cycle and a refuge from adverse conditions, such as drought. They are a good example of coastal brackish and freshwater marshes, with an important ecological and hydrological role as part of a large wetland
complex.

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This paper reviews the appropriateness for application to large data sets of standard machine learning algorithms, which were mainly developed in the context of small data sets. Sampling and parallelisation have proved useful means for reducing computation time when learning from large data sets. However, such methods assume that algorithms that were designed for use with what are now considered small data sets are also fundamentally suitable for large data sets. It is plausible that optimal learning from large data sets requires a different type of algorithm to optimal learning from small data sets. This paper investigates one respect in which data set size may affect the requirements of a learning algorithm — the bias plus variance decomposition of classification error. Experiments show that learning from large data sets may be more effective when using an algorithm that places greater emphasis on bias management, rather than variance management.

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The implementation of eCommerce technologies has considerably changed how employees in the banking industry interact with customers. For example, some customers use electronic banking applications to such an extent that they find little or no need to go into a branch. This change has had a significant impact on the way that jobs are designed and the way that employees are being managed. The preliminary findings from the case study of a large bank in Australia indicate that moving customers out of the branch to an online environment has created unforeseen issues for the way employees interact with customers and this in turn has changed the way that they do their jobs. The key challenge for banks in the future is how to form effective relationships with customers without some kind of face-to-face interaction. This impacts how organisations recruit and retain their staff as well as the level and type of skills required for jobs redesigned after the implementation of eCommerce applications. It is also an important factor in employee satisfaction.

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Aims and objectives: To examine the impact and obstacles that individual Institutional Research Ethics Committee (IRECs) had on a large-scale national multi-centre clinical audit called the National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes Study.

Background
: Multi-centre research is commonplace in the health care system. However, IRECs continue to fail to differentiate between research and quality audit projects.

Methods: The National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes study used an investigator-developed questionnaire concerning a clinical audit for heart failure programmes throughout Australia. Ethical guidelines developed by the National governing body of health and medical research in Australia classified the National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes Study as a low risk clinical audit not requiring ethical approval by IREC.

Results
: Fifteen of 27 IRECs stipulated that the research proposal undergo full ethical review. None of the IRECs acknowledged: national quality assurance guidelines and recommendations nor ethics approval from other IRECs. Twelve of the 15 IRECs used different ethics application forms. Variability in the type of amendments was prolific. Lack of uniformity in ethical review processes resulted in a six- to eight-month delay in commencing the national study.

Conclusions
: Development of a national ethics application form with full ethical review by the first IREC and compulsory expedited review by subsequent IRECs would resolve issues raised in this paper. IRECs must change their ethics approval processes to one that enhances facilitation of multi-centre research which is now normative process for health services.

Relevance to clinical practice: The findings of this study highlight inconsistent ethical requirements between different IRECs. Also highlighted are the obstacles and delays that IRECs create when undertaking multi-centre clinical audits. However, in our clinical practice it is vital that clinical audits are undertaken for evaluation purposes. The findings of this study raise awareness of inconsistent ethical processes and highlight the need for expedient ethical review for clinical audits.

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We have developed expedient and reliable methods to isolate cyclosporin synthetase for in vitro biosynthesis of cyclosporins. We have examined enzyme purification strategies suited to large-scale processing and present a chromatographic sequence that serves as a pilot model for industrial scale preparation of cyclosporin synthetase from cyclosporin producing fungi. A chromatographic sequence consisting of ammonium sulfate precipitation → gel filtration → hydrophobic interaction chromatography → anion exchange chromatography, yielded an electrophoretically homogeneous cyclosporin synthetase preparation (Coomassie G-250 brilliant blue staining). Furthermore, a native polyacrylamide gel electrophoresis system was developed for the isolation of active cyclosporin synthetase enzyme from crude extracts of cyclosporin producing fungi. The environmental factors affecting enzyme stability and the continuity of the in vitro cyclosporin biosynthetic reaction-temperature, pH, and substrate depletion were assessed and manageable conditions have been defined for sustainable cyclosporin biosynthesis with enzyme isolates. Cyclosporin synthetase exhibited an optimal temperature range of 24–29 °C and a pH optimum of 7.6. The native enzyme displayed a pI of 5.7, as determined by isoelectric focusing. The industrial implementation of an in vitro biosynthetic approach could potentially prove useful for the production of important therapeutic cyclosporins which occur as only minor fermentation by-products.

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OBJECTIVE—Gestational diabetes mellitus (GDM) is an increasingly prevalent risk factor for the development of type 2 diabetes in the mother and is  responsible for morbidity in the child. To better identify women at risk of developing GDM we examined sociodemographic correlates and changes in the prevalence of GDM among all births between 1995 and 2005 in Australia's largest state.
RESEARCH DESIGN AND METHODS—A computerized database of all births (n = 956,738) between 1995 and 2005 in New South Wales, Australia, was used in a multivariate logistic regression that examined the association between sociodemographic characteristics and the occurrence of GDM.
RESULTS—Between 1995 and 2005, the prevalence of GDM increased by 45%, from 3.0 to 4.4%. Women born in South Asia had the highest adjusted odds ratio (OR) of any region (4.33 [95% CI 4.12–4.55]) relative to women born in Australia. Women living in the three lowest socioeconomic quartiles had higher adjusted ORs for GDM relative to women in the highest quartile (1.54 [1.50–1.59], 1.74 [1.69–1.8], and 1.65 [1.60–1.70] for decreasing socioeconomic status quartiles). Increasing age was strongly associated with GDM, with women aged >40 years having an adjusted OR of 6.13 (95% CI 5.79–6.49) relative to women in their early 20s. Parity was associated with a small reduced risk. There was no association between smoking and GDM.
CONCLUSIONS—Maternal age, socioeconomic position, and ethnicity are important correlates of GDM. Future culturally specific interventions should target prevention of GDM in these high-risk groups.

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This thesis examines the nature, extent and impact of multiple forms of maltreatment (multi-type maltreatment) from within a developmental victimological framework. The interrelationships between sexual abuse, physical abuse, psychological maltreatment, neglect, and witnessing family violence are assessed. The role of family variables in predicting maltreatment and the relative contribution of child maltreatment and family variables to adjustment are evaluated. Risk factors for multi-type maltreatment, and the relationship between multi-type maltreatment and adjustment are explored. The major theories of child development are reviewed. As well as exploring the relevance of developmental theories to understanding the impact of child maltreatment, factors influencing the emergence of child psychopathology are reviewed from a developmental psychopathology perspective. Ecological and developmental perspectives on how child maltreatment translates into the behavioural and emotional adjustment problems of children are integrated in the Child Maltreatment: Risk and Protection Model. After exploring some of the relevant conceptual issues, the literature on the prevalence and impact of each maltreatment type is reviewed, and the literature on multi-type maltreatment critiqued. Methodological and ethical concerns with the conduct of research in the field of child maltreatment using direct assessment of children led to the need for an instrument to assess parent perceptions of each of the types of abuse and neglect, as well as adult retrospective reports. Data are presented from two cross-sectional questionnaire-based studies using the Parent and Adult versions of the Family and Life Experiences Questionnaire which was designed to assess perceptions of children's experiences of sexual abuse, physical abuse, psychological maltreatment, neglect and witnessing family violence. Problems with the isolated focus of research on single forms of child maltreatment are addressed by the inclusion of each of these forms of child maltreatment within a single research design. Respondents for both studies were volunteers recruited from counselling agencies, medical, community health, child care and fitness centres and a first year psychology course. Parents (N=50) described their perceptions of primary school children's family characteristics, experiences of maltreatment and adjustment. Children's behavioural adjustment (internalising and externalising), sexual behaviours, emotions, self-esteem, gender identity, family adaptability and cohesion, parental traditionality, parental sexual punitiveness, interparental relationship satisfaction, and demographic characteristics are assessed in the study of Parents' perceptions. A large degree of overlap between the different types of abuse and neglect was found, with a high proportion of parents describing children's experiences of multiple forms of child maltreatment. Using both maltreatment and family characteristics to predict internalising behaviour problems, neglect and family cohesion were the only unique predictors. Family adaptability and cohesion were the only unique predictors of externalising behaviour problems. Physical and sexual abuse were not predicted from family characteristics; neglect was predicted, but no variables provided unique prediction. Unique predictors of psychological maltreatment were family cohesion, parental sexual punitiveness and divorce. Divorce was the only variable with significant unique prediction of the child witnessing family violence. Family background and family functioning were found to predict some forms of maltreatment, but to also be important factors mediating the adjustment of children, independent of maltreatment. The results are interpreted within an ecological framework, integrating risk factors for maltreatment with experiences of abuse and neglect and subsequent adjustment in childhood. Retrospective reports of adults' (N=175) own childhood family characteristics, experiences of maltreatment, and reports of their current adjustment are also studied. Included with the adult version of the FLEQ were the Trauma Symptom Checklist-40, Rosenberg's Self-esteem Scale, and the Family and Adaptability and Cohesion Evaluation Scale-II. Similar results were found in the in the Adult Study. As hypothesised, adult retrospective reports of the five different types of child maltreatment were found to be highly intercorrelated. Family characteristics predicted maltreatment and adjustment scores and discriminated between single and multi-type maltreatment. Maltreatment scores also predicted adult adjustment. As the number of maltreatment types increased, there was an increase in the number of adjustment problems reported. Alternate hypotheses regarding the possible operation of mediating and moderating processes in the relationships between family characteristics, maltreatment and the adjustment of adults were assessed. Finally, the results of these investigations are discussed and interpreted in the light of extant findings previously reviewed. Data from the two major empirical studies are used to demonstrate the overlap between different child maltreatment categories, and the extent and impact of multi-type maltreatment. The results show that children are vulnerable to more than one type of maltreatment. Individuals who experience a number of different forms of maltreatment had greater adjustment problems than those experiencing only one or two different types of abuse or neglect. Dysfunctional families place children at risk of child maltreatment. Negative family characteristics lead to adjustment problems in children and adults. The type of maltreatment having the most damaging effect on children was neglect, and in the long-term, sexual abuse. A multi-dimensional approach to prevention and intervention needs to be adopted, based on the co-morbidity of maltreatment types, and the likelihood of children experiencing further abuse or neglect of a different type. Dysfunctional family dynamics which place children at risk of multi-type maltreatment, and mediate the effects of maltreatment on adjustment, need to be specifically targeted with support and family intervention strategies. Risk-assessment measures used by Child Protection workers must include adequate knowledge of the inter-relationships between maltreatment types, and the particularly negative impact on adjustment of experiencing many forms of abuse or neglect. Suggestions for future clinical and research work in the area of child maltreatment are developed. The importance of assessing all forms of maltreatment when examining the relationships of maltreatment to adjustment is emphasised. It is recommended that prevention and intervention strategies acknowledge the interrelationships between maltreatment types.