The Gearbox Reliability Collaborative has conducted extensive field and dynamometer test campaigns on two heavily instrumented wind turbine gearboxes. In this study, the load sharing behaviour between six bearings in the planetary stage is described using a combined approach of measurement and simulation. First, planet-bearing data are analysed to characterise planetary stage behaviour in different environments. Second, a method is described for integrating the measured responses of the planetary stage into an advanced model of the bearing life that significantly changes the life prediction. Third, a sensitivity study of the planet bearings is conducted using multibody gearbox models. Various levels of gearbox flexibility and different planet assembly fits are investigated and compared with experimental observations. Measurements in the dynamometer and field show that bearing loading differs significantly between the six planet bearings. The relative loading behaviour of the planetary stage bearings is directly influenced by boundary conditions of the planet carrier pins. Assembly differences between two identically designed gearboxes cause different load sharing behaviour. Simulations are used to quantify the effect of different component flexibilities. Reduced order models are developed to accurately predict bearing loading in a cost-efficient manner.

Environmental conditions play a major role in shaping reptilian embryonic development, but studies addressing the impact of interactions between chronic and acute environmental stressors on embryonic systems are lacking. In the present study, we investigated thermal dependence of cholinergic and adrenergic cardiovascular tone in embryonic American alligators (Alligator mississippiensis) and assessed possible phenotypic plasticity in a chronic hypoxic incubation treatment. We compared changes in heart rate (f H) and mean arterial blood pressure (P M) for chronically hypoxic and normoxic-incubated embryos after cholinergic and adrenergic blockade following three different acute temperature treatments: (1) 30 °C (control incubation temperature), (2) acute, progressive decrease 30-24 °C then held at 24 °C, and (3) acute, progressive increase 30-36 °C then held at 36 °C. f H progressively fell in response to decreasing temperature and rose in response to increasing temperature. P M did not significantly change with decreasing temperature, but was lowered significantly with increasing acute temperature in the normoxic group at 90 % of development only. Propranolol administration (β adrenergic antagonist) produced a significant f H decrease at 24, 30, and 36 °C that was similar at all temperatures for all groups. For normoxic-incubated embryos at 90 % of development, atropine administration (cholinergic antagonist) significantly increased f H in both 24 and 36 °C treatments, but not in the 30 °C control treatment. This atropine response at 24 and 36 °C demonstrated acute thermally dependent cholinergic tone on f H late in development for normoxic-incubated, but not chronically hypoxic-incubated embryos. Collectively, data indicated that cardiovascular control mechanisms in embryonic alligators may be activated by thermal extremes, and the maturation of control mechanisms was delayed by chronic hypoxia.

Phenotypic flexibility is critical in determining fitness. As conditions change during ontogeny, continued responsiveness is necessary to meet the demands of the environment. Studies have shown that subsequent ontogenetic periods of development can interact with one another and shape developmental outcomes. The role genetic variation within populations plays in shaping these outcomes remains unclear. Four full-sib families of zebrafish Danio rerio were raised under for dietary regimes: high food rations for 60 days (HH), low food rations for 60 days (LL), high food rations for 30 days followed by low food rations for 30 (HL), and low food rations for 30 days followed by high food rations for 30 (LH). While the low ration diet significantly reduced body length at 30 days, diet was no longer a significant factor at day 60. Only family level variation influenced body length. Furthermore, there was significant family level variation in the manner in which swimming performance responded to fluctuating dietary conditions. Some families increased swimming performance in response to dietary change, while others did not. These results suggest that plastic responsiveness to subsequent environmental changes can be trait specific and vary significantly within populations.

Background: Nerve transfer surgery has the potential to restore upper limb function in patients with spinal cord injury (SCI); however, there has been limited exploration of patient perception of nerve transfer. Objective: To explore the perspectives of patients with chronic SCI (>2 years from injury) on nerve transfer surgery, and to determine if an educational intervention improved participants' perceived knowledge levels about the procedure. Design: Mixed-methods study including qualitative semi-structured interviews and self-reported rating scales. Pre-and post-interviews were completed following an educational presentation. Setting: Two local SCI clinics. Participants: Ten patients with chronic traumatic SCI and neurological level of injury C3-C7 (motor complete or incomplete), recruited via snowball sampling (six male, four female). Intervention: An educational slide presentation on nerve transfer concepts. Main Outcome Measures: The primary study outcome measure is the participants' responses to interview questions. The secondary study outcome measure is their self-reported knowledge levels of nerve transfer before and after education. Results: Regaining upper limb function was a priority for all participants. Although most participants had heard of nerve transfer, none were offered it at the time of their SCI, and only two stated that they had any peers who had undergone the procedure. The educational module significantly increased selfrated scores on understanding of nerve transfer (p < .05). Although all participants were open to nerve transfer after the educational module, they described weighing different factors, including (1) potential for loss versus gain of function, (2) inadequate knowledge about nerve transfer, (3) recovery time, and (4) determining their eligibility for the surgery. Conclusions: These findings suggest that people with SCI have limited understanding of nerve transfer as a potential option and would benefit from educational opportunities to help them make informed decisions. This study may inform the development of patient resources to improve pre-surgical consultation and informed decision-making.

ObjectivesThis study was conducted to investigate the microbial contamination of caffeine citrate 10 mg/mL oral solution (CCOS) during a simulated in-use test in a clinical environment.MethodsA real-time in-use simulation study was conducted in a neonatal intensive care unit at a UK National Health Service hospital. Following the simulation, samples of the product were taken and assessed for microbiological contamination.ResultsThis study shows that CCOS does not comply with the European Pharmacopoeia (Ph Eur) Specification for Preservative Efficacy. However, it shows that the in-use contamination of the product in a clinical environment remained within the Ph Eur General Text (5.1.4) Specification for the Microbiological Quality of Non-Sterile Pharmaceutical Preparations.DiscussionThere is a requirement for medicines to be developed and formulated specifically for paediatric use. This requires that excipients should be kept to a minimum. CCOS has been specifically developed to treat apnoea of prematurity in neonates. This product does not contain antimicrobial preservatives. It is produced as a terminally sterilised solution to enable an appropriate shelf-life. CCOS is currently marketed as a unit dose product, and once opened has an immediate-use, single-patient requirement. This gives CCOS an expensive unit cost. A suitable in-use shelf-life would reduce unit dose costs.ConclusionsThe evidence from this study would suggest that CCOS, a product specifically formulated for use in neonates without antimicrobial preservatives, can safely be assigned a 7-day room temperature in-use shelf-life.