154 resultados para DIFFERENTIATED DUOPOLY


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Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables. Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037). These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC. © 2005 American Association for Cancer Research.

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This paper reports on first year experiences of international students who use English as an additional language (EAL) in higher education in Australia. It examines how valued resources can foster a positive educational experience of these students from sociological perspectives. It draws data from an interview study, exploring narrative accounts of 17 EAL international students from nine countries about their educational relations and strategies across their first year of study. Their narratives were analysed through Bourdieu's concepts of field, habitus, capital and legitimation, as well as tools of narrative inquiry. The paper finds that the students took up strategies to realign their capital portfolios with new rules of the game. Their decisions were dependent on their personal trajectories and conditions on offer. This paper suggests that more effort needs to be made to understand international students' differentiated access to valued resources in higher education.

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Osteochondral grafts are common treatment options for joint focal defects due to their excellent functionality. However, the difficulty is matching the topography of host and graft(s) surfaces flush to one another. Incongruence could lead to disintegration particularly when the gap reaches subchondoral region. The aim of this study is therefore to investigate cell response to gap geometry when forming cartilage-cartilage bridge at the interface. The question is what would be the characteristics of such a gap if the cells could bridge across to fuse the edges? To answer this, osteochondral plugs devoid of host cells were prepared through enzymatic decellularization and artificial clefts of different sizes were created on the cartilage surface using laser ablation. High density pellets of heterologous chondrocytes were seeded on the defects and cultured with chondrogenic differentiation media for 35 days. The results showed that the behavior of chondrocytes was a function of gap topography. Depending on the distance of the edges two types of responses were generated. Resident cells surrounding distant edges demonstrated superficial attachment to one side whereas clefts of 150 to 250 µm width experienced cell migration and anchorage across the interface. The infiltration of chondrocytes into the gaps provided extra space for their proliferation and laying matrix; as the result faster filling of the initial void space was observed. On the other hand, distant and fit edges created an incomplete healing response due to the limited ability of differentiated chondrocytes to migrate and incorporate within the interface. It seems that the initial condition of the defects and the curvature profile of the adjacent edges were the prime determinants of the quality of repair; however, further studies to reveal the underlying mechanisms of cells adapting to and modifying the new environment would be of particular interest.

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Several I- and A-type granite, syenite plutons and spatially associated, giant Fe–Ti–V deposit-bearing mafic ultramafic layered intrusions occur in the Pan–Xi(Panzhihua–Xichang) area within the inner zone of the Emeishan large igneous province (ELIP). These complexes are interpreted to be related to the Emeishan mantle plume. We present LA-ICP-MS and SIMS zircon U–Pb ages and Hf–Nd isotopic compositions for the gabbros, syenites and granites from these complexes. The dating shows that the age of the felsic intrusive magmatism (256.2 ± 3.0–259.8 ± 1.6 Ma) is indistinguishable from that of the mafic intrusive magmatism (255.4 ± 3.1–259.5 ± 2.7 Ma) and represents the final phase of a continuous magmatic episode that lasted no more than 10 Myr. The upper gabbros in the mafic–ultramafic intrusions are generally more isotopically enriched (lower eNd and eHf) than the middle and lower gabbros, suggesting that the upper gabbros have experienced a higher level of crustal contamination than the lower gabbros. The significantly positive eHf(t) values of the A-type granites and syenites (+4.9 to +10.8) are higher than those of the upper gabbros of the associated mafic intrusion, which shows that they cannot be derived by fractional crystallization of these bodies. They are however identical to those of the mafic enclaves (+7.0 to +11.4) and middle and lower gabbros, implying that they are cogenetic. We suggest that they were generated by fractionation of large-volume, plume-related basaltic magmas that ponded deep in the crust. The deep-seated magma chamber erupted in two stages: the first near a density minimum in the basaltic fractionation trend and the second during the final stage of fractionation when the magma was a low density Fe-poor, Si-rich felsic magma. The basaltic magmas emplaced in the shallowlevel magma chambers differentiated to form mafic–ultramafic layered intrusions accompanied by a small amount of crustal assimilation through roof melting. Evolved A-type granites (synenites and syenodiorites) were produced dominantly by crystallization in the deep crustal magma chamber. In contrast, the I-type granites have negative eNd(t) [-6.3 to -7.5] and eHf(t) [-1.3 to -6.7] values, with the Nd model ages (T Nd DM2) of 1.63-1.67 Ga and Hf model ages (T Hf DM2) of 1.56-1.58 Ga, suggesting that they were mainly derived from partial melting of Mesoproterozoic crust. In combination with previous studies, this study also shows that plume activity not only gave rise to reworking of ancient crust, but also significant growth of juvenile crust in the center of the ELIP.

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According to a study conducted by the International Maritime organisation (IMO) shipping sector is responsible for 3.3% of the global Greenhouse Gas (GHG) emissions. The 1997 Kyoto Protocol calls upon states to pursue limitation or reduction of emissions of GHG from marine bunker fuels working through the IMO. In 2011, 14 years after the adoption of the Kyoto Protocol, the Marine Environment Protection Committee (MEPC) of the IMO has adopted mandatory energy efficiency measures for international shipping which can be treated as the first ever mandatory global GHG reduction instrument for an international industry. The MEPC approved an amendment of Annex VI of the 1973 International Convention for the Prevention of Pollution from Ships (MARPOL 73/78) to introduce a mandatory Energy Efficiency Design Index (EEDI) for new ships and the Ship Energy Efficiency Management Plan (SEEMP) for all ships. Considering the growth projections of human population and world trade the technical and operational measures may not be able to reduce the amount of GHG emissions from international shipping in a satisfactory level. Therefore, the IMO is considering to introduce market-based mechanisms that may serve two purposes including providing a fiscal incentive for the maritime industry to invest in more energy efficient manner and off-setting of growing ship emissions. Some leading developing countries already voiced their serious reservations on the newly adopted IMO regulations stating that by imposing the same obligation on all countries, irrespective of their economic status, this amendment has rejected the Principle of Common but Differentiated Responsibility (the CBDR Principle), which has always been the cornerstone of international climate change law discourses. They also claimed that negotiation for a market based mechanism should not be continued without a clear commitment from the developed counters for promotion of technical co-operation and transfer of technology relating to the improvement of energy efficiency of ships. Against this backdrop, this article explores the challenges for the developing counters in the implementation of already adopted technical and operational measures.

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International shipping is responsible for about 2.7% of the global emissions of CO2. In the absence of proper action, emissions from the maritime sector may grow by 150% to 250% by 2050, in comparison with the level of emissions in 2007. Against this backdrop, the International Maritime Organisation has introduced a mandatory Energy Efficiency Design Index (EEDI) for new ships and the Ship Energy Efficiency Management Plan (SEEMP) for all ships. Some Asian countries have voiced serious reservations about the newly adopted IMO regulations. They have suggested that imposing the same obligations on all countries, irrespective of their economic status, is a serious departure from the Principle of Common but Differentiated Responsibility, which has always been the cornerstone of international climate change law discourse. Against this backdrop, this article presents a brief overview of the technical and operational measures from the perspective of Asian countries.

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The international climate regime is in the process of negotiating a legally binding instrument concerning Reducing Emissions from Deforestation and Degradation (REDD+). The paper starts by exploring the complex web of decisions and advices that currently regulate REDD+ initiatives within the international climate regime. This is followed by an analysis of justice issues raised by non-state actors in the REDD+ international negotiations. The paper concludes by building on this analysis to identify some relevant considerations when seeking to design a just and legally binding REDD+ instrument. These considerations include: the impact of market- versus fund-based investment channels, the importance of defining a clear objective; the inclusion and role of international principles such as sovereignty, preventative action, common but differentiated responsibility, sustainable development, and Free, Prior, and Informed Consent; the appropriate design of REDD+ safeguards and the inclusion of grievance mechanisms within the instrument which provide guidance on resolving disputes associated with REDD+ investment.

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Introduction The clinically known importance of patient sex as a major risk factor for compromised bone healing is poorly reflected in animal models. Consequently, the underlying cellular mechanisms remain elusive. Because mesenchymal stem cells (MSCs) are postulated to regulate tissue regeneration and give rise to essential differentiated cell types, they may contribute to sex-specific differences in bone healing outcomes. Methods We investigated sex-specific variations in bone healing and associated differences in MSC populations. A 1.5 mm osteotomy gap in the femora of 8 male and 8 female 12-month-old Sprague-Dawley rats was stabilized by an external fixator. Healing was analyzed in terms of biomechanical testing, bridging and callus size over time (radiography at 2, 4, and 6 weeks after surgery), and callus volume and geometry by μCT at final follow-up. MSCs were obtained from bone marrow samples of an age-matched group of 12 animals (6 per gender) and analyzed for numbers of colony-forming units (CFUs) and their capacity to differentiate and proliferate. The proportion of senescent cells was determined by β-galactosidase staining. Results Sex-specific differences were indicated by a compromised mechanical competence of the callus in females compared with males (maximum torque at failure, p = 0.028). Throughout the follow-up, the cross-sectional area of callus relative to bone was reduced in females (p ≤ 0.01), and the bridging of callus was delayed (p 2weeks = 0.041). μCT revealed a reduced callus size (p = 0.003), mineralization (p = 0.003) and polar moment of inertia (p = 0.003) in female animals. The female bone marrow contained significantly fewer MSCs, represented by low CFU numbers in both femora and tibiae (p femur = 0.017, p tibia = 0.010). Functional characteristics of male and female MSCs were similar. Conclusion Biomechanically compromised and radiographically delayed bone formation were distinctive in female rats. These differences were concomitant with a reduced number of MSCs, which may be causative for the suboptimal bone healing.

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Recent scholarship has considered the implications of the rise of voluntary private standards in food and the role of private actors in a rapidly evolving, de-facto ‘mandatory’ sphere of governance. Standards are an important element of this globalising private sphere, but are an element that has been relatively peripheral in analyses of power in agri-food systems. Sociological thought has countered orthodox views of standards as simple tools of measurement, instead understanding their function as a governance mechanism that transforms many things, and people, during processes of standardisation. In a case study of the Australian retail supermarket duopoly and the proprietary standards required for market access this paper foregrounds retailers as standard owners and their role in third-party auditing and certification. Interview data from primary research into Australia’s food standards captures the multifaceted role supermarkets play as standard-owners, who are found to impinge on the independence of third-party certification while enforcing rigorous audit practices. We show how standard owners, in attempting to standardize the audit process, generate tensions within certification practices in a unique example of ritualism around audit. In examining standards to understand power in contemporary food governance, it is shown that retailers are drawn beyond standard-setting into certification and enforcement, that is characterized by a web of institutions and actors whose power to influence outcomes is uneven.

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During the Senate Inquiry into 'milk price wars' in 2011, Senator Nick Xenophon accused the Australian Competition and Consumer Commission (ACCC) of being 'less effective than a toothless Chihuahua'. This follows the ACCC's lack of action regarding the reported abuse of market power of Australia's supermarket duopoly, where an extensive inquiry into the competitiveness of retail prices in 2008 found grocery retailing to be 'workably competitive' despite numerous claims to the contrary. How can farmers' submissions to the inquiry that cite market abuse be reconciled with the ACCC's finding that all is well in the food supply chain? Following an in-depth examination of 53 farmer submissions to the inquiry, we conclude that the findings of the ACCC are commensurate with the neoliberal economisation of the political sphere, where commercial entities 'legitimately' govern beyond their corporate boundaries, often using disciplinary measures that were once exclusive to governments. We argue that such clear structural inequalities between farmers and major corporations is reason to re-regulate markets and reinsert a stronger role for government to 'level the playing field'.

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The position(s) of carbon-carbon double bonds within lipids can dramatically affect their structure and reactivity and thus has a direct bearing on biological function. Commonly employed mass spectrometric approaches to the characterization of complex lipids, however, fail to localize sites of unsaturation within the molecular structure and thus cannot distinguish naturally occurring regioisomers. In a recent communication \[Thomas, M. C.; Mitchell, T. W.; Blanksby, S. J. J. Am. Chem. Soc. 2006, 128, 58-59], we have presented a new technique for the elucidation of double bond position in glycerophospholipids using ozone-induced fragmentation within the source of a conventional electrospray ionization mass spectrometer. Here we report the on-line analysis, using ozone electrospray mass spectrometry (OzESI-MS), of a broad range of common unsaturated lipids including acidic and neutral glycerophospholipids, sphingomyelins, and triacylglycerols. All lipids analyzed are found to form a pair of chemically induced fragment ions diagnostic of the position of each double bond(s) regardless of the polarity, the number of charges, or the adduction (e.g., \[M - H](-), \[M - 2H](2-), \[M + H](+), \[M + Na](+), \[M + NH4](+)). The ability of OzESI-MS to distinguish lipids that differ only in the position of the double bonds is demonstrated using the glycerophosphocholine standards, GPCho(9Z-18:1/9Z-18:1) and GPCho(6Z-18:1/6Z-18:1). While these regioisomers cannot be differentiated by their conventional tandem mass spectra, the OzESI-MS spectra reveal abundant fragment ions of distinctive mass-to-charge ratio (m/z). The approach is found to be sufficiently robust to be used in conjunction with the m/z 184 precursor ion scans commonly employed for the identification of phosphocholine-containing lipids in shotgun lipidomic analyses. This tandem OzESI-MS approach was used, in conjunction with conventional tandem mass spectral analysis, for the structural characterization of an unknown sphingolipid in a crude lipid extract obtained from a human lens. The OzESI-MS data confirm the presence of two regioisomers, namely, SM(d18:0/15Z-24:1) and SM(d18:0/17Z-24:1), and suggest the possible presence of a third isomer, SM(d18:0/19Z-24:1), in lower abundance. The data presented herein demonstrate that OzESI-MS is a broadly applicable, on-line approach for structure determination and, when used in conjunction with established tandem mass spectrometric methods, can provide near complete structural characterization of a range of important lipid classes. As such, OzESI-MS may provide important new insight into the molecular diversity of naturally occurring lipids.

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Local representations of the significance of Albany, Western Australia, in the first world war and of the city's part in the birth of Anzac register substantial points of departure from national histories. While both the Anzac mythos and official renderings of Australia's wars are vigorously contested, Albany's reformulation offers a clear example of the ways in which communities actively inflect national narratives to create expressions of differentiated local identity. This article explores the relationship between the national and the local by focusing on the local narrative of the massing and departure of'The Great Anzac Convoy' in King George Sound in 1914. Particular attention is given to the way Albany has been able to appropriate and localise this event and the origins of Anzac, consequently promoting itself as an important element of the national identity, from which it nevertheless remains distinct. This localisation of an important element of national identity confers cultural standing and a potentially empowered position in relation to this national identity.

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Preserving the integrity of the skin's outermost layer (the epidermis) is vital for humans to thrive in hostile surroundings. Covering the entire body, the epidermis forms a thin but impenetrable cellular cordon that repels external assaults and blocks escape of water and electrolytes from within. This structure exists in a perpetual state of regeneration where the production of new cellular subunits at the base of the epidermis is offset by the release of terminally differentiated corneocytes from the surface. It is becoming increasingly clear that proteases hold vital roles in assembling and maintaining the epidermal barrier. More than 30 proteases are expressed by keratinocytes or infiltrating immune cells and the activity of each must be maintained within narrow limits and confined to the correct time and place. Accordingly, over- or under-exertion of proteolytic activity is a common factor in a multitude of skin disorders that range in severity from relatively mild to life-threatening. This review explores the current state of knowledge on the involvement of proteases in skin diseases and the latest findings from proteomic and transcriptomic studies focused on uncovering novel (patho)physiological roles for these enzymes.

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We report a novel technology for the rapid healing of large osseous and chondral defects, based upon the genetic modification of autologous skeletal muscle and fat grafts. These tissues were selected because they not only possess mesenchymal progenitor cells and scaffolding properties, but also can be biopsied, genetically modified and returned to the patient in a single operative session. First generation adenovirus vector carrying cDNA encoding human bone morphogenetic protein-2 (Ad.BMP-2) was used for gene transfer to biopsies of muscle and fat. To assess bone healing, the genetically modified (“gene activated”) tissues were implanted into 5mm-long critical size, mid-diaphyseal, stabilized defects in the femora of Fischer rats. Unlike control defects, those receiving gene-activated muscle underwent rapid healing, with evidence of radiologic bridging as early as 10 days after implantation and restoration of full mechanical strength by 8 weeks. Histologic analysis suggests that the grafts rapidly differentiated into cartilage, followed by efficient endochondral ossification. Fluorescence in situ hybridization detection of Y-chromosomes following the transfer of male donor muscle into female rats demonstrated that at least some of the osteoblasts of the healed bone were derived from donor muscle. Gene activated fat also healed critical sized defects, but less quickly than muscle and with more variability. Anti-adenovirus antibodies were not detected. Pilot studies in a rabbit osteochondral defect model demonstrated the promise of this technology for healing cartilage defects. Further development of these methods should provide ways to heal bone and cartilage more expeditiously, and at lower cost, than is presently possible.

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This study investigated the relative contribution of individual, workplace, psychosocial and physiological features associated with neck pain in female office workers towards developing appropriate intervention programs. Workers without disability (Neck Disability Index (NDI) score≤8, n=33); workers with neck pain and disability (NDI≥9/100, n=52) and 22 controls (women who did not work and without neck pain) participated in this study. Two logistic regression models were constructed to test the association between various measures in (1) workers with and without disability, and (2) workers without disability and controls. Measures included those found to be significantly associated with higher NDI in our previous studies: psychosocial domains; individual factors; task demands; quantitative sensory measures and measures of motor function. In the final model, higher score on negative affectivity scale (OR=4.47), greater activity in the neck flexors during cranio-cervical flexion (OR=1.44), cold hyperalgesia (OR=1.27) and longer duration of symptoms (OR=1.19) remained significantly associated with neck pain in workers. Workers without disability and controls could only be differentiated by greater muscle activity in the cervical flexors and extensors during a typing task. No psychosocial domains remained in either regression model. These results suggest that impairments in the sensory and motor system should be considered in any assessment of the office worker with neck pain and may have stronger influences on the presenting symptoms than workplace and psychosocial features.