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Notes: A technique is described for fabrication of a remount cast for a removable partial denture. This procedure consists of filling the occlusal/incisal third with acrylic resin and injecting polyvinylsiloxane impression material into the irreversible hydrocolloid impression. This technique provides a simple method for making a remount cast and enables the clinician to remove and easily place the partial denture on the cast during occlusal refinement procedures without damage to the removable partial denture or the remount cast.

Notes: Inhibition of the mitochondrial electron transport chain (ETC) ultimately limits ATP production and depletes cellular ATP. However, the individual complexes of the ETC in brain mitochondria need to be inhibited by ∼ 50% before causing significant depression of ATP synthesis. Moreover, the ETC is the key site for the production of intracellular reactive oxygen species (ROS) and inhibition of one or more of the complexes of the ETC may increase the rate of mitochondrial ROS generation. We asked whether partial inhibition of the ETC, to a degree insufficient to perturb oxidative phosphorylation, might nonetheless induce ROS production. Chronic increase in mitochondrial ROS might then cause oxidative damage to the ETC sufficient to produce prolonged changes in ETC function and so compound the defect. We show that the exposure of astrocytes in culture to low concentrations of nitric oxide (NO) induces an increased rate of O2·− generation that outlasts the presence of NO. No effect was seen on oxygen consumption, lactate or ATP content over the 4–6 h that the cells were exposed to NO. These data suggest that partial ETC inhibition by NO may initially cause oxidative stress rather than ATP depletion, and this may subsequently induce irreversible changes in ETC function providing the basis for a cycle of damage.

Notes: Apoptosis may be initiated in neurons via mitochondrial release of the respiratory protein, cytochrome c. The mechanism of cytochrome c release has been studied extensively, but little is known about its dynamics. It has been claimed that release is all-or-none, however, this is not consistent with accumulating evidence of cytosolic mechanisms for ‘buffering’ cytochrome c. This study has attempted to model an underlying disease pathology, rather than inducing apoptosis directly. The model adopted was diminished activity of the mitochondrial respiratory chain complex I, a recognized feature of Parkinson's disease. Titration of rat brain mitochondrial respiratory function, with the specific complex I inhibitor rotenone, caused proportional release of cytochrome c from isolated synaptic and non-synaptic mitochondria. The mechanism of release was mediated, at least in part, by the mitochondrial outer membrane component Bak and voltage-dependent anion channel rather than non-specific membrane rupture. Furthermore, preliminary data were obtained demonstrating that in primary cortical neurons, titration with rotenone induced cytochrome c release that was subthreshold for the induction of apoptosis. Implications for the therapy of neurodegenerative diseases are discussed.

Notes:   Following an outline of the different types of agglomeration economy, consideration is given to transaction costs. Transaction costs may have a definite spatial dimension because institutional, commercial, cultural, and language characteristics are differentiated across the geographic space separating market agents. The concept of transaction space is introduced to represent the spatial differentiation of these characteristics, and this concept is used to cast light on how space can contribute to coordination and agency problems that raise transaction costs. Contractual agreements that are rearranged, so as to span a less heterogeneous transaction space, permit the reduction of transaction costs. Agglomeration can then be interpreted as an alternative to hierarchical structures within firms in economizing on transaction costs. The paper concludes with illustrations of how this framework may help to understand the spatial implications of corporate restructuring and new information technologies.

Notes: Aims  The present study sought to replicate and extend a small pilot study conducted by Baker, Boggs & Lewin (2001) which demonstrated that brief interventions consisting of motivational interviewing and cognitive-behaviour therapy (CBT) were feasible and associated with better outcomes compared with a control condition.Design  Randomized controlled trial (RCT).Setting  Greater Brisbane Region of Queensland and Newcastle, NSW, Australia.Participants  The study was conducted among 214 regular amphetamine users.Measurements  Demographic characteristics, past and present alcohol and other drug use and mental health, treatment, amphetamine-related harms and severity of dependence.Findings  The main finding of this study was that there was a significant increase in the likelihood of abstinence from amphetamines among those receiving two or more treatment sessions. In addition, the number of treatment sessions attended had a significant short-term beneficial effect on level of depression. There were no intervention effects on any other variables (HIV risk-taking, crime, social functioning and health). Overall, there was a marked reduction in amphetamine use among this sample over time and, apart from abstinence rates and short-term effects on depression level, this was not differential by treatment group. Reduction in amphetamine use was accompanied by significant improvements in stage of change, benzodiazepine use, tobacco smoking, polydrug use, injecting risk-taking behaviour, criminal activity level, and psychiatric distress and depression level.Conclusions  A stepped-care approach is recommended. The first step in providing an effective intervention among many regular amphetamine users, particularly those attending non-treatment settings, may include provision of: a structured assessment of amphetamine use and related problems; self-help material; and regular monitoring of amphetamine use and related harms. Regular amphetamine users who present to treatment settings could be offered two sessions of CBT, while people with moderate to severe levels of depression may best be offered four sessions of CBT for amphetamine use from the outset, with further treatment for amphetamine use and/or depression depending on response. Pharmacotherapy and/or longer-term psychotherapy may be suitable for non-responders. An RCT of a stepped-care approach among regular amphetamine users is suggested.

Notes: Aims  To examine the risk posed by cannabis use in young people for tobacco use disorders. Specifically we examined whether cannabis use in non-smokers predicted later initiation of tobacco use and whether cannabis use predicted later nicotine dependence in tobacco users.Design  A 10-year eight-wave cohort study.Setting  State of Victoria, Australia.Participants  A community sample of 1943 participants initially aged 14–15 years.Measurements  Self-report of tobacco and cannabis use was assessed in the teens using a computerized interview assessment and in young adulthood with a CATI assessment. The Fagerström Test for Nicotine Dependence was used to define nicotine dependence.Findings  For teen non-smokers, at least one report of weekly cannabis use in the teens predicted a more than eightfold increase in the odds of later initiation of tobacco use (OR 8.3; 95% CI 1.9–36). For 21-year-old smokers, not yet nicotine-dependent, daily cannabis use raised the odds of nicotine dependence at the  age  of  24 years  more  than  threefold  (OR  3.6,  1.2,  10)  after  controlling  for possible confounders, including level of tobacco use and subsyndromal signs of nicotine dependence.Conclusions  Weekly or more cannabis use during the teens and young adulthood is associated with an increased risk of late initiation of tobacco use and progression to nicotine dependence. If this effect is causal, it may be that a heightened risk of nicotine dependence is the most important health consequence of early frequent cannabis use.

Notes: Juvenile trees of temperate and boreal regions cease growth and set buds in autumn in response to short day-lengths (SD) detected by phytochrome. Growth cessation and bud set are prerequisites for the development of winter dormancy and full cold hardiness. In this study we show that the SD-requirement for bud set and cold hardening can be overcome in hybrid aspen (Populus tremula L. × tremuloides Michx.) by low night temperature and inhibition of gibberellin (GA) biosynthesis. Bud set and increased cold hardiness were observed under normally non-inductive long day-length (LD) in wild-type plants, when exposed to low night temperature and paclobutrazol. In addition, the effect of PHYA overexpression could be overcome in transgenic plants, producing bud set and cold acclimation by treatment with: SD, low night temperature and paclobutrazol. After cold acclimation, the degree of bud dormancy was lower for wild-type plants prior treated with LD and transgenic plants (overexpressing PHYA), than SD-treated, wild-type plants. Thus, low night temperature in combination with reduced GA content induced bud set and promoted cold hardiness under normally non-inductive photoperiods in hybrid aspen, but was unable to affect development of dormancy. This might suggest separate signalling pathways from phytochrome regulating the induction of cold/cold hardiness and bud dormancy in hybrid aspen or alternatively, there might be one pathway that fails to complete its action in the transgenic and paclobutrazol treated plants.

Notes: AH neurons in the enteric nervous system play an essential role in initiating intestinal reflexes and factors that control AH neuron excitability therefore influence the state of the digestive system. Prominent afterhyperpolarizations that follow action potentials in these neurons strongly affect their excitability. In the present work, we have investigated the regulation of the afterhyperpolarizing current (IAHP) by protein kinase C (PKC). Electrophysiological responses and protein translocation were investigated in AH neurons of freshly dissected preparations of myenteric ganglia from the guinea-pig ileum. The activator of conventional and novel PKCs, phorbol dibutyrate, but not the activator of novel PKCs, ingenol, blocked the IAHP. Phorbol dibutyrate had no effect on the hyperpolarization-activated current (Ih) or on the A current (IA). Stimulation of synaptic inputs to the neurons also reduced the IAHP, and had no effect on Ih or IA. Phorbol dibutyrate also reduced a background outward current that was present after the IAHP current had been blocked by clotrimazole. Both phorbol dibutyrate and ingenol caused translocation of the novel PKC, PKCε, in these neurons. Only phorbol dibutyrate caused translocation of PKCγ, a conventional PKC. The studies thus indicate that the activation of PKC by phorbol esters and by nerve stimulation affects AH neurons in a similar way, and that PKC activation targets both the IAHP and another background K+ current. The IAHP is targeted by a conventional PKC, suggested to be PKCγ, as this is the only conventional PKC that is prominent in AH neurons.

Notes: Abstract.  A classification of the locational patterns of firms (with economies of scale and scope present) is outlined in order to shed light on the location of the multiplant, multinational firm, which is driven by three forces: spatial economies of scale and scope that follow from the co-location of different activities sharing a common fixed input; transportation costs on the final good; and factor-mobility costs. We conclude that the single-plant firm prevails when spatial economies of scale and scope are pronounced, while multi-plant firms emerge when spatial economies of scale and scope are weak. However, the vertical multinational firm is to be found when transportation costs on the finished good are low, whereas the horizontal multinational firm emerges when these costs are high. The vertical multinational thus appears as the limit in the evolution of the market structure for most consumer goods.

Notes: Purpose - This essay reflects a profound sense of frustration with the concept of leadership and the enormous and every increasing body of research and pontification about it. Given the ongoing failure to define leadership as a coherent construct, it aims to argue that continuing along this omni-directional path is not likely to produce anything truly useful for those who study, teach about or work in organizations; rather, abandoning the concept altogether and emphasizing a focus on improving decision making in organizations may prove more fruitful. Design/methodology/approach - Looks at different concepts of leadership and the enormous and ever-increasing body of research and pontification about it. Findings - In the end, however, the author believes that we are mostly left with endless discussions and perspectives of a word that simply sounds better. We seem to remain intent on calling almost everything leadership - but, if everything is leadership, then logically nothing is leadership. Originality/value - This review is a useful source of information for anyone interested in the concept of leadership.