59 research outputs found
Synthesis of carbon nanotubes with and without catalyst particles
The initial development of carbon nanotube synthesis revolved heavily around the use of 3d valence transition metals such as Fe, Ni, and Co. More recently, noble metals (e.g. Au) and poor metals (e.g. In, Pb) have been shown to also yield carbon nanotubes. In addition, various ceramics and semiconductors can serve as catalytic particles suitable for tube formation and in some cases hybrid metal/metal oxide systems are possible. All-carbon systems for carbon nanotube growth without any catalytic particles have also been demonstrated. These different growth systems are briefly examined in this article and serve to highlight the breadth of avenues available for carbon nanotube synthesis
Acceptability of the 6-PACK falls prevention program: A pre-implementation study in hospitals participating in a cluster randomized controlled trial
There is limited evidence to support the effectiveness of falls prevention interventions in the acute hospital setting. The 6-PACK falls prevention program includes a fall-risk tool; 'falls alert' signs; supervision of patients in the bathroom; ensuring patients' walking AIDS are within reach; toileting regimes; low-low beds; and bed/chair alarms. This study explored the acceptability of the 6-PACK program from the perspective of nurses and senior staff prior to its implementation in a randomised controlled trial. A mixed-methods approach was applied involving 24 acute wards from six Australian hospitals. Participants were nurses working on participating wards and senior hospital staff including: Nurse Unit Managers; senior physicians; Directors of Nursing; and senior personnel involved in quality and safety or falls prevention. Information on program acceptability (suitability, practicality and benefits) was obtained by surveys, focus groups and interviews. Survey data were analysed descriptively, and focus group and interview data thematically. The survey response rate was 60%. Twelve focus groups (n = 96 nurses) and 24 interviews with senior staff were conducted. Falls were identified as a priority patient safety issue and nurses as key players in falls prevention. The 6-PACK program was perceived to offer practical benefits compared to current practice. Nurses agreed fall-risk tools, low-low beds and alert signs were useful for preventing falls (>70%). Views were mixed regarding positioning patients' walking aid within reach. Practical issues raised included access to equipment; and risk of staff injury with low-low bed use. Bathroom supervision was seen to be beneficial, however not always practical. Views on the program appropriateness and benefits were consistent across nurses and senior staff. Staff perceived the 6-PACK program as suitable, practical and beneficial, and were open to adopting the program. Some practical concerns were raised highlighting issues to be addressed by the implementation plan
Psychosocial issues of women with type 1 diabetes transitioning to motherhood: a structured literature review
BACKGROUND: Life transitions often involve complex decisions, challenges and changes that affect diabetes management. Transition to motherhood is a major life event accompanied by increased risk that the pregnancy will lead to or accelerate existing diabetes-related complications, as well as risk of adverse pregnancy outcomes, all of which inevitably increase anxiety. The frequency of hyperglycaemia and hypoglycaemia often increases during pregnancy, which causes concern for the health and physical well-being of the mother and unborn child. This review aimed to examine the experiences of women with T1DM focusing on the pregnancy and postnatal phases of their transition to motherhood. METHODS: The structured literature review comprised a comprehensive search strategy identifying primary studies published in English between 1990-2012. Standard literature databases were searched along with the contents of diabetes-specific journals. Reference lists of included studies were checked. Search terms included: 'diabetes', 'type 1', 'pregnancy', 'motherhood', 'transition', 'social support', 'quality of life' and 'psychological well-being'. RESULT: Of 112 abstracts returned, 62 articles were reviewed in full-text, and 16 met the inclusion criteria. There was a high level of diversity among these studies but three common key themes were identified. They related to physical (maternal and fetal) well-being, psychological well-being and social environment. The results were synthesized narratively. CONCLUSION: Women with type 1 diabetes experience a variety of psychosocial issues in their transition to motherhood: increased levels of anxiety, diabetes-related distress, guilt, a sense of disconnectedness from health professionals, and a focus on medicalisation of pregnancy rather than the positive transition to motherhood. A trusting relationship with health professionals, sharing experiences with other women with diabetes, active social support, shared decision and responsibilities for diabetes management assisted the women to make a positive transition. Health professionals can promote a positive transition to motherhood by proactively supporting women with T1DM in informed decision-making, by facilitating communication within the healthcare team and co-ordinating care for women with type 1 diabetes transitioning to motherhood
Autophagy fights disease through cellular self-digestion
Autophagy, or cellular self-digestion, is a cellular pathway involved in protein and organelle degradation, with an astonishing number of connections to human disease and physiology. For example, autophagic dysfunction is associated with cancer, neurodegeneration, microbial infection and ageing. Paradoxically, although autophagy is primarily a protective process for the cell, it can also play a role in cell death. Understanding autophagy may ultimately allow scientists and clinicians to harness this process for the purpose of improving human health.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62766/1/nature06639.pd
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Evaluation of the prognostic role of centromere 17 gain and HER2/topoisomerase II alpha gene status and protein expression in patients with breast cancer treated with anthracycline-containing adjuvant chemotherapy: pooled analysis of two Hellenic Cooperative Oncology Group (HeCOG) phase III trials
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