Andrew Keen

Bio: Andrew Keen is an academic researcher from University of Aberdeen. The author has contributed to research in topics: Nitrobacter & Fibromyalgia. The author has an hindex of 4, co-authored 5 publications receiving 238 citations. Previous affiliations of Andrew Keen include Boston Children's Hospital.

Does mindfulness improve outcomes in patients with chronic pain? Systematic review and meta-analysis

Abstract: Background Chronic pain and its associated distress and disability are common reasons for seeking medical help. Patients with chronic pain use primary healthcare services five times more than the rest of the population. Mindfulness has become an increasingly popular self-management technique. Aim To assess the effectiveness of mindfulness-based interventions for patients with chronic pain. Design and setting Systematic review and meta-analysis including randomised controlled trials of mindfulness-based interventions for chronic pain. There was no restriction to study site or setting. Method The databases MEDLINE®, Embase, AMED, CINAHL, PsycINFO, and Index to Theses were searched. Titles, abstracts, and full texts were screened iteratively against inclusion criteria of: randomised controlled trials of mindfulness-based intervention; patients with non-malignant chronic pain; and economic, clinical, or humanistic outcome reported. Included studies were assessed with the Yates Quality Rating Scale. Meta-analysis was conducted. Results Eleven studies were included. Chronic pain conditions included: fibromyalgia, rheumatoid arthritis, chronic musculoskeletal pain, failed back surgery syndrome, and mixed aetiology. Papers were of mixed methodological quality. Main outcomes reported were pain intensity, depression, physical functioning, quality of life, pain acceptance, and mindfulness. Economic outcomes were rarely reported. Meta-analysis effect sizes for clinical outcomes ranged from 0.12 (95% confidence interval [CI] = −0.05 to 0.30) (depression) to 1.32 (95% CI = −1.19 to 3.82) (sleep quality), and for humanistic outcomes 0.03 (95% CI = −0.66 to 0.72) (mindfulness) to 1.58 (95% CI = −0.57 to 3.74) (pain acceptance). Studies with active, compared with inactive, control groups showed smaller effects. Conclusion There is limited evidence for effectiveness of mindfulness-based interventions for patients with chronic pain. Better-quality studies are required.

Assessing competence in cognitive-behavioural therapy.

Abstract: Background Postgraduate courses on cognitive–behavioural therapy (CBT) assess various competencies using essays, case studies and audiotapes or videotapes of clinical work. Aims To evaluate how reliably a well-established postgraduate course assesses CBT competencies. Method Data were collected on two cohorts of trainees ( n =52). Two examiners marked trainees on: (a) two videotapes of clinical practice; (b) two case studies; and (c) three essays. Results Essay examinations were more reliable than case studies, which in turn were more reliable than videotaped assessments. The reliability of the latter two assessments was considerably lower than that commonly expected of high-stakes examinations. To assess reliably standard CBT competencies, postgraduate courses would need to examine about 5 essays, 12 case studies and 19 videotapes. Conclusions Reliable assessment of standard competencies is complex and resource intensive. There would need to be a marked increase in the number of samples of clinical work assessed to be able to make reliable judgements about proficiency.

The Surface Growth and Activity of Nitrobacter

Abstract: The effect of surface attachment on oxidation of nitrite to nitrate byNitrobacter was studied in batch culture, on glass coverslips, and in continuous culture on glass beads and anion exchange resin beads in an air-lift column fermenter. In batch culture, the surfaces stimulated specific growth rate, while in continuous culture, activity of attached cells was less than that of freely suspended cells. Nitrate productivity, free cell productivity, and attached cell concentration increased exponentially at the same specific rate, termed the colonization rate, and nitrate productivity was found to be a convenient estimate of biomass concentration. Permanent attachment was mediated by production of slime material. Surface growth resulted in multiple steady states and the ability to respond quickly to changes in dilution rate. The air-lift column fermenter system provided a convenient system for the study of growth and activity of attached cells and was most suitable when using ion exchange resins as a substratum for attachment.

Assessing the Communication Skills of Doctors in Training: Reliability and Sources of Error

Abstract: Medical examining bodies now commonly assess candidates' communication skills. However, there are a number of within-case sources of error that can mean examinations have poor reliability and validity. The aims of this study were to determine the main within-case sources of error and to identify the best methods of maximising reliability in highly structured communication skills assessments. Subjects were fifth year medical students at the University of Aberdeen. Subjects were videotaped giving clinical information to standardised patients and relatives toward the end of their fifth year and toward the end of their pre-registration year. Sources of variation, reliability coefficients and the most effective methods of reducing measurement error were calculated using generalisability theory. Systematic differences among subjects' communication skill was the main source of variation in two of the three assessment cases. The implications of the results are discussed.

Video-based computer-assisted learning.

Abstract: As a relevant exemplar of MPEG-1 and MPEG-2 digital video use, a multimedia computer-assisted learning (CAL) application dealing with Critical Communication Issues in medicine was developed. The application allowed the student to navigate through a series of high-quality digital video and audio clips that were delivered in near real-time from an Intranet server. This paper gives a brief background to the MPEG-2 video compression system and discusses the use of digital video in a CAL environment.

Autotrophic nitrification in bacteria

Abstract: Publisher Summary This chapter highlights the physiology of autotrophic ammonia- and nitrite-oxidizing bacteria. Several aspects of the physiology of nitrifiers of relevance to their growth and activity in natural environments are considered. The chapter describes the basic features of the biochemistry of ammonia and nitrite oxidation and discusses the growth limiting factors and activity of these organisms. The influence of oxygen concentration, pH value, and inhibitors on their physiology is also described. Nitrification plays a central role in the nitrogen cycle of terrestrial and aquatic ecosystems, converting the most reduced form of nitrogen, NH3, to the most oxidized form, NO3. Nitrifying bacteria occupy niches in many ecosystems and compete successfully with faster and more efficiently growing organisms for oxygen, ammonia, and carbon dioxide. Nitrifiers are capable of reversing the nitrification process, carrying out denitrification and producing nitrite, ammonia, nitrous and nitric oxides, and gaseous nitrogen. Ammonia oxidizers can metabolize urea and can assimilate carbon from methane while nitrite oxidizers can grow anaerobically in the presence of organic compounds and nitrate.

Mindfulness Meditation for Chronic Pain: Systematic Review and Meta-analysis

Abstract: Background Chronic pain patients increasingly seek treatment through mindfulness meditation.

Effects of salinity on NH4 + adsorption capacity, nitrification, and denitrification in Danish estuarine sediments

Abstract: The regulatory effect of salinity on nitrogen dynamics in estuarine sediments was investigated in the Randers Fjord estuary, Denmark, using sediment slurries and intact sediment cores and applying 15N-isotope techniques. Sediment was sampled at three representative stations varying in salinity, and all experiments were run at 0‰, 10‰, 20‰, and 30‰. The sediment NH4 + adsorption capacity decreased markedly at all stations when salinity was increased from 0‰ to 10‰; further increase showed little effect. In situ nitrification and denitrification also decreased with increasing salinities, with the most pronounced reduction of approximately 50% being observed when the salinity was raised from 0‰ to 10‰. The salinity-induced reduction in NH4 + adsorption capacity and stimulation of NH4 + efflux has previously been argued to cause a reduction in nitrification activity since the nitrifying bacteria become limited by NH4 + availability at higher salinities. However, using a potential nitrification assay where NH4 + was added in excess, it was demonstrated that potential nitrification activity also decreased with increasing salinity, indicating that the inhibitory salinity effect may also be a physiological effect on the microorganisms. This hypothesis was supported by the finding that denitrification based on NO3 − from the overlying water (Dw), which is independent of the nitrification process, and hence NH4 + availability, also decreased with increasing salinity. We conclude that changes in salinity have a significant effect on nitrogen dynamics in estuarine sediments, which must be considered when nitrogen transformations are measured and evaluated.

Effects of Salinity on NH4+ Adsorption Capacity, Nitrification, and

Abstract: The regulatory effect of salinity on nitrogen dynamics in estuarine sediments was investigated in the Randers Fjord estuary, Denmark, using sediment slurries and intact sediment cores and applying 15N-isotope techniques. Sediment was sampled at three representative stations varying in salinity, and all experiments were run at 0%o, 10%o, 20%o, and 30%o. The sediment NH4+ adsorption capacity decreased markedly at all stations when salinity was increased from 0%o to 10%o; further increase showed little effect. In situ nitrification and denitrification also decreased with increasing salinities, with the most pronounced reduction of approximately 50% being observed when the salinity was raised from 0%o to 10%o. The salinity-induced reduction in NH4+ adsorption capacity and stimulation of NH4+ efflux has previously been argued to cause a reduction in nitrification activity since the nitrifying bacteria become limited by NH4+ availability at higher salinities. However, using a potential nitrification assay where NH4+ was added in excess, it was demonstrated that potential nitrification activity also decreased with increasing salinity, indicating that the inhibitory salinity effect may also be a physiological effect on the microorganisms. This hypothesis was supported by the finding that denitrification based on N03- from the overlying water (Dw), which is independent of the nitrification process, and hence NH4+ availability, also decreased with increasing salinity. We conclude that changes in salinity have a significant effect on nitrogen dynamics in estuarine sediments, which must be considered when nitrogen transformations are mea- sured and evaluated.