932 resultados para DESTRUCTIVE INTERFERENCE


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Periodontitis results from the destructive inflammatory reaction of the host elicited by a bacterial biofilm adhering to the tooth surface and if left untreated, may lead to the loss of the teeth and the surrounding tissues, including the alveolar bone. Cementum is a specialized calcified tissue covering the tooth root and an essential part of the periodontium which enables the attachment of the periodontal ligament to the root and the surrounding alveolar bone. Periodontal ligament cells (PDLCs) represent a promising cell source for periodontal tissue engineering. Since cementogenesis is the critical event for the regeneration of periodontal tissues, this study examined whether inorganic stimuli derived from bioactive bredigite (Ca7MgSi4O16) bioceramics could stimulate the proliferation and cementogenic differentiation of PDLCs, and further investigated the involvement of the Wnt/β-catenin signalling pathway during this process via analysing gene/protein expression of PDLCs which interacted with bredigite extracts. Our results showed that the ionic products from bredigite powder extracts led to significantly enhanced proliferation and cementogenic differentiation, including mineralization–nodule formation, ALP activity and a series of bone/cementum-related gene/protein expression (ALP, OPN, OCN, BSP, CAP and CEMP1) of PDLCs in a concentration dependent manner. Furthermore, the addition of cardamonin, a Wnt/β-catenin signalling inhibitor, reduced the pro-cementogenesis effect of the bredigite extracts, indicating the involvement of the Wnt/β-catenin signalling pathway in the cementogenesis of PDLCs induced by bredigite extracts. The present study suggests that an entirely inorganic stimulus with a specific composition of bredigite bioceramics possesses the capacity to trigger the activation of the Wnt/β-catenin signalling pathway, leading to stimulated differentiation of PDLCs toward a cementogenic lineage. The results indicate the therapeutic potential of bredigite ceramics in periodontal tissue engineering application.

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The validity of the Multidimensional School Anger Inventory (MSAI) was examined with adolescents from 5 Pacific Rim countries (N ¼ 3,181 adolescents; age, M ¼ 14.8 years; 52% females). Confirmatory factor analyses examined configural invariance for the MSAI’s anger experience, hostility, destructive expression, and anger coping subscales. The model did not converge for Peruvian students. Using the top 4 loaded items for anger experience, hostility, and destructive expression configural invariance and partial metric and scalar invariances were found. Latent means analysis compared mean responses on each subscale to the U.S. sample. Students from other countries showed higher mean responses on the anger experience subscale (ds ¼ .37–.73). Australian (d ¼ .40) and Japanese students (d ¼ .21) had significantly higher mean hostility subscale scores. Australian students had higher mean scores on the destructive expression subscale (d ¼ .30), whereas Japanese students had lower mean scores (d ¼ 2.17). The largest latent mean gender differences (females lower than males) were for destructive expression among Australian (d ¼ 2.67), Guatemalan (d ¼ 2.42), and U.S. (d ¼ 2.66) students. This study supported an abbreviated, 12-item MSAI with partial invariance. Implications for the use of the MSAI in comparative research are discussed.

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This thesis is a qualitative study aimed at better capturing the complexity of conflict in family businesses. An inductive content analysis revealed two important issues: the dynamics of intergenerational conflicts and the escalation process of conflicts. The results demonstrated that conflicts are more likely to be intergenerational than intra-generational due to the role of senior members in daily business operations, generational differences, and a perception gap that exist between generations concerning each other’s competencies in doing the business. Furthermore, the set of factors contributing to conflict escalation is related to how family members handle the conflict, how they manage their emotions, and how they are able to avoid non-family employee involvement. These findings provide a foundation for taking preventative actions, implementing strategies for managing conflicts or devising effective solutions for resolving conflicts before they become more destructive.

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Banana is one of the world’s most popular fruit crops and Sukali Ndizi is the most popular dessert banana in the East African region. Like other banana cultivars, Sukali Ndizi is threatened by several constraints, of which the Fusarium wilt disease is the most destructive. Fusarium wilt is caused by a soil-borne fungus, Fusarium oxysporum f.sp. cubense (Foc). No effective control strategy currently exists for this disease and although disease resistance exists in some banana cultivars, introducing resistance into commercial cultivars by conventional breeding is difficult because of low fertility. Considering that conventional breeding generates hybrids with additional undesirable traits, transformation is the most suitable way of introducing resistance in the banana genome. The success of this strategy depends on the availability of genes for genetic transformation. Recently, a novel strategy involving the expression of anti-apoptosis genes in plants was shown to result in resistance against several necrotrophic fungi, including Foc race 1 in banana cultivar Lady Finger. This thesis explores the potential of a plant-codon optimised nematode anti-apoptosis gene (Mced9) to provide resistance against Foc race 1 in dessert banana cultivar Sukali Ndizi. Agrobacterium-mediated transformation was used to transform embryogenic cell suspension of Sukali Ndizi with plant expression vector pYC11, harbouring maize ubiquitin promoter driven Mced9 gene and nptII as a plant selection marker. A total of 42 independently transformed lines were regenerated and characterized. The transgenic lines were multiplied, infected and evaluated for resistance to Foc race 1 in a small pot bioassay. The pathogenicity of the Ugandan Foc race 1 isolate used for infection was pre-determined and the spore concentration was standardised for consistent infection and symptom development. This process involved challenging tissue culture plants of Sukali Ndizi, a Foc race 1 susceptible cultivar and Nakinyika, an East African Highland cultivar known to be resistant to Foc race 1, with Fusarium inoculum and observing external and internal disease symptom development. Rhizome discolouration symptoms were the best indicators of Fusarium wilt with yellowing being an early sign of disease. Three transgenic lines were found to show significantly less disease severities compared to the wild-type control plants after 13 weeks of infection, indicating that Mced9 has the potential to provide tolerance to Fusarium wilt in Sukali Ndizi.

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Alcohol consumption is enmeshed with Australian culture (Palk, 2008) and the use and misuse of alcohol contributes to considerable health and social harms (Barbor et al., 2010; English et al., 1995; Gutjahr, Gmel, & Rehm, 2001; Palk, 2008; Steenkamp, Harrison, & Allsop, 2002). Despite shifts in the way that alcohol is consumed and how it is used, it has been reported that one-third of all alcohol consumed is done so within licensed premises (Lang, Stockwell, Rydon, & Gamble, 1992). Consequently, licensed premises are over-represented as settings in which alcohol-related harms occur. These harms, particularly those related to violence, are associated with particular licensed premises operating in the night-time economy (Briscoe & Donnelly, 2001b; Chikritzhs, Stockwell, & Masters, 1997; Homel, Tomsen, & Thommeny, 1991; Stockwell, 1997). Police have a role in not only responding to the manifestation of harms, such as crime, injuries, assaults, domestic violence, stealing and sexual offences, but they also have a role in preventing problems, and thereby reducing alcohol and other drug-related harms (Doherty & Roche, 2003). Given the extent of alcohol consumption within licensed premises and the nature and extent of the harms, as well as the lack of opportunity to influence outcomes in other settings (e.g. the home), licensed premises offer police and other stakeholders a significant opportunity to influence positively the reduction of alcoholrelated harm. This research focuses specifically on the police role in policing licensed premises. Primarily, this research aims to investigate the factors which are relevant to why and how police officers respond to alcohol-related incidents inside and outside licensed premises. It examines the attitudes and beliefs of police and assesses their knowledge, capacity and ability to effectively police licensed premises. The research methodology uses three distinct surveys. Each contributes to understanding the motivations and practice of police officers in this important area of harm reduction. Study One involved a survey of police officers within a police district (Brisbane Central District) in Queensland, Australia and used a comprehensive questionnaire involving both quantitative and qualitative techniques. A key research outcome of Study One was the finding that officers had low levels of knowledge of the strategies that are effective in addressing alcohol-related harm both inside and outside licensed premises. Paradoxically, these officers also reported extensive recent experience in dealing with alcohol issues in these locations. In addition, these officers reported that alcohol was a significant contextual factor in the majority of matters to which they responded. Officers surveyed reported that alcohol increased the difficulty of responding to situations and that licensed premises (e.g. nightclubs, licensed clubs and hotels) were the most difficult contexts to police. Those surveyed were asked to self-assess their knowledge of the Liquor Act (Qld), which is the primary legislative authority in Queensland for regulating licensed premises. Surprisingly, well over half of the officers (65%) reported ‘no’ to ‘fair’ knowledge of the Act, despite officers believing that their skill level to police such premises was in the ‘good to very good range’. In an important finding, officers reported greater skill level to police outside licensed premises than inside such premises, indicating that officers felt less capable, from a skill perspective, to operate within the confines of a licensed premise than in the environment immediately outside such premises. Another key finding was that officers reported greater levels of training in responding to situations outside and around licensed premises than to situations inside licensed premises. Officers were also asked to identify the frequency with which they employed specified regulatory enforcement and community-based strategies. Irrespective of the type of response, ‘taking no action’ or passive policing interventions were not favoured by officers. The findings identified that officers favoured taking a range of strategies (sending home, releasing into the custody of friends, etc.) in preference to arrest. In another key finding, officers generally reported their support for operational stakeholder partnership approaches to policing licensed premises. This was evidenced by the high number of officers (over 90%) reporting that there should be shared responsibility for enforcing the provisions of the Liquor Act. Importantly, those surveyed also identified the factors which constrain or prevent them from policing licensed premises. Study Two involved interviewing a small but comprehensive group (n=11) of senior managers from within the Queensland Police Service (QPS) who have responsibility for setting operational and strategic policy. The aim of this study was to examine the attitudes, perceptions and influence that senior officers (at the strategy and policy-setting level) had on the officers at the operational level. This qualitative study was carried out using a purposive sampling (Denzin & Lincoln, 2005; Guba & Lincoln, 1989), focused interview and thematic analytic approach. The interview participants were drawn from three tiers of management at district, regional as well as the whole-of-organisational level. The first key theme emerging from the study related to role, in terms of both the QPS broader organisational role, and the individual officer role with respect to the policing of licensed premises. For the QPS organisational role, participants at all three strategic levels had a high degree of congruity as to the organisations service role; that is, to enhance public safety. With respect to participants’ beliefs as to whether police officers have knowledge and understanding of their individual roles concerning licensed premises (as opposed to the QPS role), participants reported most commonly that officers had a reasonable to clear understanding of their role. Participant comments also were supportive of the view that officers operating in the research area, Brisbane Central District (BCD), had a clearer understanding of their role than police operating in other locations. The second key theme to emerge identified a disparity between the knowledge and capability of specialist police, compared with general duties police, to police licensed premises. In fact, a number of the responses to a variety of questions differentiated specialist and general police in a range of domains. One such example related to the clarity of understanding of officer role. Participants agreed that specialist police (Liquor Enforcement & Proactive Strategies [LEAPS] officers) had more clarity of understanding in terms of their role than generalist police. Participants also were strongly of the opinion that specialist police had higher skill levels to deal with issues both inside and outside licensed premises. Some participants expressed the view that general duty police undertook purely response-related activities, or alternatively, dealt with lower order matters. Conversely, it was viewed that specialist police undertook more complex tasks because of their higher levels of knowledge and skill. The third key theme to emerge concerned the identification of barriers that serve to restrict or prevent police officers from policing licensed premises. Participant responses strongly indicated that there was a diversity of resourcing barriers that restrict police from undertaking their roles in licensed premises. Examples of such barriers were the lack of police and the low ratio of police to patrons, available officer time, and lack of organisational investment in skills and knowledge acquisition. However, some participants indicated that police resourcing in the BCD was appropriate and officers were equipped with sufficient powers (policy and legislation). Again, the issue of specialist police was raised by one participant who argued that increasing the numbers of specialist police would ameliorate the difficulties for police officers policing licensed premises. The fourth and last key theme to emerge from Study Two related to the perception of senior officers regarding the opportunity and capability of officers to leverage off external partnerships to reduce harms inside and outside licensed premises. Police working in partnership in BCD was seen as an effective harm reduction strategy and strongly supported by the participants. All participants demonstrated a high degree of knowledge as to who these partners were and could identify those government, non-government and community groups precisely. Furthermore, the majority of participants also held strong views that the partnerships were reasonably effective and worked to varying degrees depending on the nature of the partnership and issues such as resourcing. These senior officers identified better communication and coordination as factors that could potentially strengthen these partnerships. This research finding is particularly important for senior officers who have the capacity to shape the policy and strategic direction of the police service, not only in Queensland but throughout Australasia. Study Three examined the perceptions of those with links to the broader liquor industry (government, non-government and community but exclusive of police) concerning their understanding of the police role and the capacity of police to reduce alcohol-related harm inside and outside licensed premises, and their attitudes towards police. Participants (n=26) surveyed represented a range of areas including the liquor industry, business represenatives and government representatives from Queensland Fire and Rescue Service, Queensland Ambulance Service, Brisbane City Council and Queensland Health. The first key theme to emerge from Study Three related to participant understanding of the QPS organisational role, and importantly, individual officer role in policing licensed premises. In terms of participant understanding of the QPS role there was a clear understanding by the majority of participants that the police role was to act in ways consistent with the law and to otherwise engage in a range of enforcement-related activities. Participants saw such activities falling into two categories. The first category related to reactive policing, which included actions around responding to trouble in licensed premises, monitoring crowd controllers and removing trouble-makers. In the second category, proactive approaches, participants identified the following activities as consistent with that approach: early intervention with offenders, support of licensed premises operators and high visibility policing. When participants were asked about their understanding of individual officer roles in the policing of licensed premises, a range of responses were received but the consistent message that emerged was that there is a different role to be played by general duty (uniformed) police compared to specialist (LEAPS Unit) police, which reflects differences in knowledge, skill and capability. The second key theme that emerged from the data related to the external participants’ views of the knowledge and capability of specialist police, compared with general duty police, to police licensed premises. As noted in the first key theme, participants were universally of the view that the knowledge, skill and capability of police in specialist units (LEAPS Unit) was at a higher level than that of general duty police. Participants observed that these specialist officers were better trained than their colleagues in generalist areas and were therefore better able to intervene knowledgeably and authoritatively to deal with problems and issues as they emerged. Participants also reported that officers working within BCD generally had a positive attitude to their duties and had important local knowledge that they could use in the resolution of alcohol-related issues. Participants also commented on the importance of sound and effective QPS leadership, as well as the quality of the leadership in BCD. On both these measures, there was general consensus from participants, who reported positively on the importance and effectiveness of such leadership in BCD. The third key theme to emerge from Study Three concerned the identification of barriers that serve to restrict or prevent police officers from policing licensed premises. Overwhelmingly, external participants reported the lack of human resources (i.e. police officers) as the key barrier. Other resourcing limitations, such as available officer time, police computer systems, and the time taken to charge offenders, were identified as barriers. Some participants identified barriers in the liquor industry such as ‘dodgy operators’ and negative media attention as limitations. Other constraints to emerge related to government and policy barriers. These were reflected in comments about the collection by government of fees from licensees and better ‘powers’ for police to deal with offenders. The fourth and final key theme that emerged from Study Three related to the opportunities for and capability of police to leverage off external partnerships to reduce harms inside and outside licensed premises. Not surprisingly, participants had a comprehensive knowledge of a broad range of stakeholders, from a diversity of contexts, influential in addressing issues in licensed premises. Many participants reported their relationships with the police and other stakeholders as effective, productive and consistent with the objectives of partnering to reduce alcohol-related harm. On the other hand, there were those who were concerned with their relationship with other stakeholders, particularly those with a compliance function (e.g. Office of Liquor & Gaming Regulation [OLGR]). The resourcing limitations of partners and stakeholders were also raised as an important constraining factor in fulfilling the optimum relationship. Again, political issues were mentioned in terms of the impact on partnerships, with participants stating that there is at times political interference and that politicians complicate the relationships of stakeholders. There are some significant strengths with respect to the methodology of this research. The research is distinguished from previous work in that it examines these critical issues from three distinct perspectives (i.e. police officer, senior manager and external stakeholder). Other strengths relate to the strong theoretical framework that guides and informs the research. There are also some identified limitations, including the subjective nature of self-report data as well as the potential for bias by the author, which was controlled for using a range of initiatives. A further limitation concerns the potential for transferability and generalisability of the findings to other locations given the distinctive nature of the BCD. These limitations and issues of transferability are dealt with at length in the thesis. Despite a growing body of literature about contextual harms associated with alcohol, and specific research concerning police intervention in such contextual harms, there is still much to learn. While research on the subject of police engaging in alcohol-related incidents has focused on police behaviours and strategies in response to such issues, there is a paucity of research that focuses on the knowledge and understanding of officers engaged in such behaviours and practices. Given the scarcity of research dealing with the knowledge, skills and attitudes of police officers responding to harms inside and outside licensed premises, this research contributes significantly to what is a recent and growing body of research and literature in the field. The research makes a practical contribution to police agencies’ understanding of officer knowledge and police practice in ways that have the potential to shape education and training agendas, policy approaches around generalist versus specialist policing, strategic and operational strategy, as well as partnership engagements. The research also makes a theoretical contribution given that the research design is informed by the Three Circle

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The nursing literature suggests that talking and listening to patients about issues associated with death and dying, is both important and difficult, and may be improved with training. This discussion presents the results of recent nursing research to confirm, and elaborate on, this theme. In this research participants touched on many central issues in communicating with patients that included articulating a sense of discomfort and inadequacy about the whole process, detailing the innumerable blocks to open communication [e.g., interference, denial, unrealistic optimism, resistance, collusion and anger] and sharing their sense of success and failure. The insights of nurses who participated in this research testify to the ongoing need to prioritize the development of nursing skills and support in this challenging but important area.

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The article focuses on how the information seeker makes decisions about relevance. It will employ a novel decision theory based on quantum probabilities. This direction derives from mounting research within the field of cognitive science showing that decision theory based on quantum probabilities is superior to modelling human judgements than standard probability models [2, 1]. By quantum probabilities, we mean decision event space is modelled as vector space rather than the usual Boolean algebra of sets. In this way,incompatible perspectives around a decision can be modelled leading to an interference term which modifies the law of total probability. The interference term is crucial in modifying the probability judgements made by current probabilistic systems so they align better with human judgement. The goal of this article is thus to model the information seeker user as a decision maker. For this purpose, signal detection models will be sketched which are in principle applicable in a wide variety of information seeking scenarios.

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A switch-mode assisted linear amplifier (SMALA) combining a linear (Class B) and a switch-mode (Class D) amplifier is presented. The usual single hysteretic controlled half-bridge current dumping stage is replaced by two parallel buck converter stages, in a parallel voltage controlled topology. These operate independently: one buck converter sources current to assist the upper Class B output device, and a complementary converter sinks current to assist the lower device. This topology lends itself to a novel control approach of a dead-band at low power levels where neither class D amplifier assists, allowing the class B amplifier to supply the load without interference, ensuring high fidelity. A 20 W implementation demonstrates 85% efficiency, with distortion below 0.08% measured across the full audio bandwidth at 15 W. The class D amplifier begins assisting at 2 W, and below this value, the distortion was below 0.03%. Complete circuitry is given, showing the simplicity of the additional class D amplifier and its corresponding control circuitry.

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The T-box family transcription factor gene TBX20 acts in a conserved regulatory network, guiding heart formation and patterning in diverse species. Mouse Tbx20 is expressed in cardiac progenitor cells, differentiating cardiomyocytes, and developing valvular tissue, and its deletion or RNA interference-mediated knockdown is catastrophic for heart development. TBX20 interacts physically, functionally, and genetically with other cardiac transcription factors, including NKX2-5, GATA4, and TBX5, mutations of which cause congenital heart disease (CHD). Here, we report nonsense (Q195X) and missense (I152M) germline mutations within the T-box DNA-binding domain of human TBX20 that were associated with a family history of CHD and a complex spectrum of developmental anomalies, including defects in septation, chamber growth, and valvulogenesis. Biophysical characterization of wild-type and mutant proteins indicated how the missense mutation disrupts the structure and function of the TBX20 T-box. Dilated cardiomyopathy was a feature of the TBX20 mutant phenotype in humans and mice, suggesting that mutations in developmental transcription factors can provide a sensitized template for adult-onset heart disease. Our findings are the first to link TBX20 mutations to human pathology. They provide insights into how mutation of different genes in an interactive regulatory circuit lead to diverse clinical phenotypes, with implications for diagnosis, genetic screening, and patient follow-up.

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Bulk amount of graphite oxide was prepared by oxidation of graphite using the modified Hummers method and its ultrasonication in organic solvents yielded graphene oxide (GO). X-ray diffraction (XRD) pattern, X-ray photoelectron (XPS), Raman and Fourier transform infrared (FTIR) spectroscopy indicated the successful preparation of GO. XPS survey spectrum of GO revealed the presence of 66.6 at% C and 30.4 at% O. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) images of the graphene oxide showed that they consist of a large amount of graphene oxide platelets with a curled morphology containing of a thin wrinkled sheet like structure. AFM image of the exfoliated GO signified that the average thickness of GO sheets is ~1.0 nm which is very similar to GO monolayer. GO/epoxy nanocomposites were prepared by typical solution mixing technique and influence of GO on mechanical and thermal properties of nanocomposites were investigated. As for the mechanical behaviour of GO/epoxy nanocomposites, 0.5 wt% GO in the nanocomposite achieved the maximum increase in the elastic modulus (~35%) and tensile strength (~7%). The TEM analysis provided clear image of microstructure with homogeneous dispersion of GO in the polymer matrix. The improved strength properties of GO/epoxy nanocomposites can be attributed to inherent strength of GO, the good dispersion and the strong interfacial interactions between the GO sheets and the polymer matrix. However, incorporation of GO showed significant negative effect on composite glass transition temperature (Tg). This may arise due to the interference of GO on curing reaction of epoxy.

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Objectives Early childhood caries is a highly destructive dental disease which is compounded by the need for young children to be treated under general anaesthesia. In Australia, there are long waiting periods for treatment at public hospitals. In this paper, we examined the costs and patient outcomes of a prevention programme for early childhood caries to assess its value for government services. Design Cost-effectiveness analysis using a Markov model. Setting Public dental patients in a low socioeconomic, socially disadvantaged area in the State of Queensland, Australia. Participants Children aged 6 months to 6 years received either a telephone prevention programme or usual care. Primary and secondary outcome measures A mathematical model was used to assess caries incidence and public dental treatment costs for a cohort of children. Healthcare costs, treatment probabilities and caries incidence were modelled from 6 months to 6 years of age based on trial data from mothers and their children who received either a telephone prevention programme or usual care. Sensitivity analyses were used to assess the robustness of the findings to uncertainty in the model estimates. Results By age 6 years, the telephone intervention programme had prevented an estimated 43 carious teeth and saved £69 984 in healthcare costs per 100 children. The results were sensitive to the cost of general anaesthesia (cost-savings range £36 043–£97 298) and the incidence of caries in the prevention group (cost-savings range £59 496–£83 368) and usual care (cost-savings range £46 833–£93 328), but there were cost savings in all scenarios. Conclusions A telephone intervention that aims to prevent early childhood caries is likely to generate considerable and immediate patient benefits and cost savings to the public dental health service in disadvantaged communities.

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The determination of the characteristics of articular cartilage such as thickness, stiffness and swelling, especially in the form that can facilitate real-time decisions and diagnostics is still a matter for research and development. This paper correlates near infrared spectroscopy with mechanically measured cartilage thickness to establish a fast, non-destructive, repeatable and precise protocol for determining this tissue property. Statistical correlation was conducted between the thickness of bovine cartilage specimens (n = 97) and regions of their near infrared spectra. Nine regions were established along the full absorption spectrum of each sample and were correlated with the thickness using partial least squares (PLS) regression multivariate analysis. The coefficient of determination (R2) varied between 53 and 93%, with the most predictive region (R2 = 93.1%, p < 0.0001) for cartilage thickness lying in the region (wavenumber) 5350–8850 cm−1. Our results demonstrate that the thickness of articular cartilage can be measured spectroscopically using NIR light. This protocol is potentially beneficial to clinical practice and surgical procedures in the treatment of joint disease such as osteoarthritis.

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Non-periodic structural variation has been found in the high Tc cuprates, YBa2Cu3O7-x and Hg0.67Pb0.33Ba2Ca2Cu 3O8+δ, by image analysis of high resolution transmission electron microscope (HRTEM) images. We use two methods for analysis of the HRTEM images. The first method is a means for measuring the bending of lattice fringes at twin planes. The second method is a low-pass filter technique which enhances information contained by diffuse-scattered electrons and reveals what appears to be an interference effect between domains of differing lattice parameter in the top and bottom of the thin foil. We believe that these methods of image analysis could be usefully applied to the many thousands of HRTEM images that have been collected by other workers in the high temperature superconductor field. This work provides direct structural evidence for phase separation in high Tc cuprates, and gives support to recent stripes models that have been proposed to explain various angle resolved photoelectron spectroscopy and nuclear magnetic resonance data. We believe that the structural variation is a response to an opening of an electronic solubility gap where holes are not uniformly distributed in the material but are confined to metallic stripes. Optimum doping may occur as a consequence of the diffuse boundaries between stripes which arise from spinodal decomposition. Theoretical ideas about the high Tc cuprates which treat the cuprates as homogeneous may need to be modified in order to take account of this type of structural variation.

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We examined acute molecular responses in skeletal muscle to repeated sprint and resistance exercise bouts. Six men [age, 24.7 ± 6.3 yr; body mass, 81.6 ± 7.3 kg; peak oxygen uptake, 47 ± 9.9 ml·kg -1 ·min -1; one repetition maximum (1-RM) leg extension 92.2 ± 12.5 kg; means ± SD] were randomly assigned to trials consisting of either resistance exercise (8 × 5 leg extension, 80% 1-RM) followed by repeated sprints (10 × 6 s, 0.75 N·m torque·kg -1) or vice-versa. Muscle biopsies from vastus lateralis were obtained at rest, 15 min after each exercise bout, and following 3-h recovery to determine early signaling and mRNA responses. There was divergent exercise order-dependent phosphorylation of p70 S6K (S6K). Specifically, initial resistance exercise increased S6K phosphorylation (?75% P < 0.05), but there was no effect when resistance exercise was undertaken after sprints. Exercise decreased IGF-I mRNA following 3-h recovery (?50%, P = 0.06) independent of order, while muscle RING finger mRNA was elevated with a moderate exercise order effect (P < 0.01). When resistance exercise was followed by repeated sprints PGC-1? mRNA was increased (REX1-SPR2; P = 0.02) with a modest distinction between exercise orders. Repeated sprints may promote acute interference on resistance exercise responses by attenuating translation initiation signaling and exacerbating ubiquitin ligase expression. Indeed, repeated sprints appear to generate the overriding acute exercise-induced response when undertaking concurrent repeated sprint and resistance exercise. Accordingly, we suggest that sprint-activities are isolated from resistance training and that adequate recovery time is considered within periodized training plans that incorporate these divergent exercise modes.

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We examined acute molecular responses in skeletal muscle to divergent exercise stimuli by combining consecutive bouts of resistance and endurance exercise. Eight men [22.9 ± 6.3 yr, body mass of 73.2 ± 4.5 kg, peak O2 uptake (V?O2peak) of 54.0 ± 5.7 ml·kg-1·min-1] were randomly assigned to complete trials consisting of either resistance exercise (8 x 5 leg extension, 80% 1 repetition maximum) followed by a bout of endurance exercise (30 min cycling, 70% V?O2peak) or vice versa. Muscle biopsies were obtained from the vastus lateralis at rest, 15 min after each exercise bout, and after 3 h of passive recovery to determine early signaling and mRNA responses. Phosphorylation of Akt and Akt1Ser473 were elevated 15 min after resistance exercise compared with cycling, with the greatest increase observed when resistance exercise followed cycling (?55%; P < 0.01). TSC2-mTOR-S6 kinase phosphorylation 15 min after each bout of exercise was similar regardless of the exercise mode. The cumulative effect of combined exercise resulted in disparate mRNA responses. IGF-I mRNA content was reduced when cycling preceded resistance exercise (-42%), whereas muscle ring finger mRNA was elevated when cycling was undertaken after resistance exercise (?52%; P < 0.05). The hexokinase II mRNA level was higher after resistance cycling (?45%; P < 0.05) than after cycling-resistance exercise, whereas modest increases in peroxisome proliferator-activated receptor gamma coactivator-1? mRNA did not reveal an order effect. We conclude that acute responses to diverse bouts of contractile activity are modified by the exercise order. Moreover, undertaking divergent exercise in close proximity influences the acute molecular profile and likely exacerbates acute "interference".