The neural correlates of phonological short-term memory: A repetitive transcranial magnetic stimulation study

Neuropsychological reports and activation studies by means of positron emission tomography anti functional magnetic resonance imaging have suggested that the neural correlates of phonological short-term memory are located in the left hemisphere, with Brodmann's area (BA) 40 being, responsible for short-term storage and BA 44 for articulatory rehearsal. However, a careful review of the literature on the role of left BA 40 shows that the data are equivocal. We tested We hypotheses by means of repetitive transcranial magnetic stimulation (rTMS). Participants performed four tasks: two phonological judgements, thought to require only articulatory rehearsal Without the contribution of short-term storage digit span, which involves both short-term storage and articudlatory rehearsal: and a pattern span, this last heing the control task. The sites of stimulation were left BA 40. left BA 44 anti the electrode location V-W plus a baseline without TMS. Reaction times increased and accuracy decreased in the case of the phonological judgement and digit span after stimulation of both left sites, suggesting that BA 40, in addition to BA 44. is involved in phonological judgements. Possible explanations are discussed, namely, the possibility that (i) the neural correlates of rehearsal are not limited to BA and (ii) phonological judgements invlove processes other than rehearsal. We also consider the effects of using different tasks and responses to resolve some of the descrepancies in the literature

Specific wavelength colorimeter

A self contained, specific wavelength, single beam colorimeter is described for direct spectrophotometric measurement of the concentration of a given solute in a test sample. An electrical circuit employing a photoconductive cell converts the optical output into a linear, directly readable meter output. The colorimeter is simple to operate and is adapted for use in zero gravity conditions. In a specific application, the colorimeter is designed to analyze the concentration of iodine in potable water carried aboard a space vehicle such as the 4B stage of Skylab

Exercise rehabilitation for recovery from critical illness (Protocol)

Queen Margaret University, Edinburgh, UK. As part of an ongoing research education programme.This is the protocol for a review and there is no abstract. The objectives are as follows: The objective of this systematic review is to assess the effectiveness of exercise rehabilitation programmes, initiated after ICU discharge, on improving functional exercise capacity and quality of life in adult ICU survivors who have been mechanically ventilated for more than 24 hours. We will compare an exercise intervention to any other intervention or a control or 'usual care' programme. Exercise includes any structured or taught programmes. Respiratory or inspiratory muscle training is excluded due to it being initiated within the ICU environment, for example with weaning from a ventilator, and not as post-discharge rehabilitation as required for this review.sch_phyAngus 1997 Angus, DC. Understanding the incidence and long-term outcomes of ARDS. In: Gullo, A editor(s). Anaesthesia, pain, intensive care and emergency medicine: a scientific report. Berlin Heidelberg New York: Springer, 1997:289-98. Angus 2003 Angus DC, Carlet J, Brussels Roundtable 2002 Participants. Surviving intensive care: a report from the 2002 Brussels Roundtable. Intensive Care Medicine 2003;29(3):368-77. [PUBMED: 12536269 ] Baumgartner 1999 Baumgartner WA,Walinsky PL, Salazar JD, Tseng EE, Brock MV, Doty JR, et al.Assessing the impact of cerebral injury after cardiac surgery: will determining the mechanism reduce the injury?. The Annals of Thoracic Surgery 1999;67(6):1871-3. [PUBMED: 10391329] Brown 1990 Brown AB, McCartney N, Sale DG. Positive adaptation to weightlifting in the elderly. Journal of Applied Physiology 1990;69(5): 1725-33. [PUBMED: 2272965] Burtin 2009 Burtin C, Clerckx B, Robbeets C, Ferdinande P, Langer D, Troosters T, et al.Early exercise in critically ill patients enhances short-term functional recovery. Critical Care Medicine 2009;37(9): 2499-505. [PUBMED: 19623052] Chaboyer 2003 Chaboyer W, Grace J. Following the path of ICU survivors: a quality improvement activity. Nursing in Critical Care 2003;8(4): 149-55. [PUBMED: 12940690] Eddleston 2000 Eddleston J, White P, Guthrie E. Survival, morbidity, and quality of life after discharge from intensive care. Critical Care Medicine 2000; 28(7):2293-9. [PUBMED: 10921555] Elliott 2006 Elliott D, McKinley S, Alison J, Aitken L, King M. Study protocol: Home-based rehabilitation for survivors of a critical illness. Critical Care 2006;10(3):R90. [PUBMED: 16792792 ] Fiatarone 1994 Fiatarone MA, O'Neill EF, Ryan ND, Clements KM, Solares GR, Nelson ME, et al.Exercise training and nutritional supplementation for physical frailty in very elderly people. New England Journal of Medicine 1994;330(25):1769-75. [PUBMED: 8190152] Fletcher 2003 Fletcher S, Kennedy D, Ghosh I, Misra V, Kiff K, et al.Persistant neuromuscular and neurophysiological abnormalities in long-term survivors of prolonged critical illness. Critical Care Medicine 2003; 31(4):1012-6. [PUBMED: 12682465] Frank 2000 Frank M, Schlapfer H, Otte B, Yasikoff N, Conzelmann M. Results of neurorehabilitation. An outcome study 20 months after stroke. Praxis 2000;89(44):1799-808. [PUBMED: 11109917] Gill 2002 Gill TM, Baker DI, Gottschalk M, Peduzzi PN, Allore H, Byers A. A program to prevent functional decline in physically frail, elderly persons who live at home. New England Journal of Medicine 2002; 347(14):1068-74. [PUBMED: 12362007] Grimby 1986 Grimby G. Physical activity and muscle training in the elderly. Acta Medica Scandinavica. Supplementum. 1986;711:233-7. [PUBMED: 3535411] Guyatt 2008 Guyatt GH, Oxman AD, Kunz R, Vist GE, Falck-Ytter Y, Schunemann HJ, et al.What is quality of evidence- and why is it important to clinicians?. BMJ 2008;336:995-8. [PUBMED: 18456631] Higgins 2008 Higgins JPT, Green S, editors. Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1 [updated September 2008]. Available from www.cochrane-handbook.org: The Cochrane Collaboration, 2008. Iversen 2003 Iversen MD, Fossel AH, Katz JN. Enhancing function in older adults with chronic low back pain: a pilot study of endurance training. Archives of Physical Medicine and Rehabilitation 2003;84 (9):1324-31. [PUBMED: 13680569] Jolliffe 2001 Jolliffe J, Rees K, Taylor RRS, Thompson DR, Oldridge N, Ebrahim S. Exercise-based rehabilitation for coronary heart disease. Cochrane Database of Systematic Reviews 2001, Issue 1. [DOI: 10.1002/14651858.CD001800.] King 1998 King J, Crowe J. Mobilisation practices in Canadian critical care units. Physiotherapy Canada 1998;50(3):206-11. [MEDLINE: 0346574] Kouidi 2002 Kouidi E. Exercise training in dialysis patients: why, when, and how?. Artificial Organs 2002;26(12):1009-13. [PUBMED: 12460377] Krishnan 2002 Krishnan KR, Delong M, Kraemer H, Carney R, Spiegel D, Gordon C, et al.Comorbidity of depression with other medical diseases in the elderly. Biological Psychiatry 2002;52(6):559-88. [PUBMED: 12361669] Lavie 2009 Lavie CJ, Thomas RJ, Squires RW, Allison TG, Milani RV. Exercise training and cardiac rehabilitation in primary and secondary prevention of coronary heart disease. Mayo Clinic Proceedings 2009; 84(4):373-83. [PUBMED: 19339657] Lewis 2003 Lewis M. Intensive care unit rehabilitation within the United Kingdom: a review. Physiotherapy 2003;89(9):531-8. [DOI: 10.1016/S0031-9406(05)60179-4] Martin 2005 Martin M, Salim A, Murray J, Demetriades D, Belzberg H, Rhee P. The decreasing incidence and mortality of acute respiratory distress syndrome after injury: a 5-year observational study. Journal of Trauma 2005;50(5):1107-13. [PUBMED: 16385287] Mazzeo 2001 Mazzeo RS, Tanaka H. Exercise prescription for the elderly: current recommendations. Sports Medicine 2001;31(11):809-18. [PUBMED: 11583105] Miller 2002 Miller MD, Crotty M, Giles LC, Bannerman E, Whitehead C, Cobiac L, et al.Corrected arm muscle area: an independent predictor of long-term mortality in community dwelling older adults?. Journal of the America Geriatrics Society 2002;50(7): 1272-7. [PUBMED: 12133024] Paffenbarger 1986 Paffenbarger RS, Hyde RT, Wing AL, Hseih CC. Physical activity, all-cause mortality, and longevity of college alumni. New England Journal of Medicine 1986;314(10):605-13. [PUBMED: 3945246] Puhan 2006 Puhan MA, Busching G, Schunemann HJ, VanOort E, Zaugg C, Frey M. Interval versus continuous high-intensity exercise in chronic obstructive pulmonary disease: a randomized trial. Annals of Internal Medicine 2006;145(11):816-25. [PUBMED: 17146066] Rantanen 2000 Rantanen T, Harris T, Leveille SG, Visser M, Foley D, et al.Muscle strength and body mass index as long-term predictors of mortality in initially healthy men. Journal of Gerontology. Series A: Biological Sciences and Medical Sciences 2000;55(3):M168-73. [PUBMED: 10795731] RevMan 5.0 The Nordic Cochrane Centre, The Cochrane Collaboration. Review Manager (RevMan). 5.0. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2008. Schweickert 2009 Schweickert WD, Pohlman MC, Pohlman AS, Nigos C, Pawlik AJ, Esbrook CL, et al.Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet 2009;373(epub):1874-82. [PUBMED: 19446324] Smith 2006 Smith TP, Kennedy SL, Smith M, Orent S, Fleshner M. Physiological improvements and health benefits during an exercisebased comprehensive rehabilitation program in medically complex patients. Exercise Immunology Review 2006;12:86-96. [PUBMED: 17201074] Stiller 2000 Stiller K. Physiotherapy in intensive care: toward an evidence-based practice. Chest 2000;118(6):1801-13. [PUBMED: 11115476] Storch 2008 Storch EK, Kruszynski DM. From rehabilitation to optimal function: role of clinical exercise therapy. Current Opinion in Critcal Care 2008;14(4):451-5. [PUBMED: 18614911] Wiles 2009 Wiles L, Stiller K. Passive limb movements for patients in an intensive care unit: A survey of physiotherapy practice in Australia. Journal of Critical Care 2009;epub:ahead of print. [PUBMED: 19819105] Yoshida 1999 Yoshida T, Kohzuki M, Yoshida K, Hiwatari M, Kamimoto M, Yamamoto C, et al.Physical and psychological improvements after phase II cardiac rehabilitation in patients with myocardial infarction. Nursing & Health Sciences 1999;1(3):163-70. [PUBMED: 10894639] Indicates the major publication for the study8pub1756pubArt.

The M87 Black Hole Mass From Gas-Dynamical Models Of Space Telescope Imaging Spectrograph Observations

The supermassive black hole of M87 is one of the most massive black holes known and has been the subject of several stellar and gas-dynamical mass measurements; however, the most recent revision to the stellar-dynamical black hole mass measurement is a factor of about two larger than the previous gas-dynamical determinations. Here, we apply comprehensive gas-dynamical models that include the propagation of emission-line profiles through the telescope and spectrograph optics to new Space Telescope Imaging Spectrograph observations from the Hubble Space Telescope. Unlike the previous gas-dynamical studies of M87, we map out the complete kinematic structure of the emission-line disk within similar to 40 pc from the nucleus, and find that a small amount of velocity dispersion internal to the gas disk is required to match the observed line widths. We examine a scenario in which the intrinsic velocity dispersion provides dynamical support to the disk, and determine that the inferred black hole mass increases by only 6%. Incorporating this effect into the error budget, we ultimately measure a mass of M-BH = (3.5(-0.7)(+0.9)) x 10(9)M circle dot (68% confidence). Our gas-dynamical black hole mass continues to differ from the most recent stellar-dynamical mass by a factor of two, underscoring the need for carrying out more cross-checks between the two main black hole mass measurement methods.NSF Astronomy and Astrophysics Postdoctoral Fellowship 1102845Space Telescope Science Institute 12162NASA NAS 5-26555NSF AST-1108835Astronom

The President's Day cyclone 17-19 February 1979: An analysis of jet streak interactions prior to cyclogenesis

The President's Day cyclone, produced record breaking snowfall along the East Coast of the United States in February 1979. Conventional radiosonde data, SMS GOES infrared imagery and LFM 2 model diagnostics were used to analyze the interaction of upper and lower tropospheric jet streaks prior to cyclogenesis. The analysis reveals that a series of complex scale interactive processes is responsible for the development of the intense cyclone. The evolution of the subsynoptic scale mass and momentum fields prior to and during the period of rapid development of the President's Day cyclone utilizing conventional data and SMS GOES imagery is documented. The interaction between upper and lower tropospheric jet streaks which occurred prior to the onset of cyclogenesis is discussed as well as the possible effects of terrain modified airflow within the precyclogenesis environment. Possible deficiencies in the LFM-2 initial wind fields that could have been responsible, in part, for the poor numerical forecast are examined

Structural sensitivity analysis: Methods, applications, and needs

Some innovative techniques applicable to sensitivity analysis of discretized structural systems are reviewed. These techniques include a finite-difference step-size selection algorithm, a method for derivatives of iterative solutions, a Green's function technique for derivatives of transient response, a simultaneous calculation of temperatures and their derivatives, derivatives with respect to shape, and derivatives of optimum designs with respect to problem parameters. Computerized implementations of sensitivity analysis and applications of sensitivity derivatives are also discussed. Finally, some of the critical needs in the structural sensitivity area are indicated along with Langley plans for dealing with some of these needs

Implications of climate change on flow regime affecting Atlantic salmon

International audienceThe UKCIP02 climate change scenarios (2070?2100) suggest that the UK climate will become warmer (an overall increase of 2.5?3°C), with temperature increases being greater in the summer and autumn than in the spring and winter seasons. In terms of precipitation, winters are expected to become wetter and summers drier throughout the UK. The effect of changes in the future climate on flow regimes are investigated for the Atlantic salmon, Salmo salar, in a case study in an upland UK river. Using a hydraulic modelling approach, flows simulated across the catchment are assessed in terms of hydraulic characteristics (discharge per metre width, flow depths, flow velocities and Froude number). These, compared with suitable characteristics published in the literature for various life stages of Atlantic salmon, enable assessment of habitat suitability. Climate change factors have been applied to meteorological observations in the Eden catchment (north-west England) and effects on the flow regime have been investigated using the SHETRAN hydrological modelling system. High flows are predicted to increase by up to 1.5%; yet, a greater impact is predicted from decreasing low flows (e.g. a Q95 at the outlet of the study catchment may decrease to a Q85 flow). Reliability, Resilience and Vulnerability (RRV) analysis provides a statistical indication of the extent and effect of such changes on flows. Results show that future climate will decrease the percentage time the ideal minimum physical habitat requirements will be met. In the case of suitable flow depth for spawning activity at the outlet of the catchment, the percentage time may decrease from 100% under current conditions to 94% in the future. Such changes will have implications for the species under the Habitats Directive and for catchment ecological flow management strategies

A Stellar Dynamical Mass Measurement of the Black Hole in NGC 3998 from Keck Adaptive Optics Observations

We present a new stellar dynamical mass measurement of the black hole in the nearby, S0 galaxy NGC 3998. By combining laser guide star adaptive optics observations obtained with the OH-Suppressing Infrared Imaging Spectrograph on the Keck II telescope with long-slit spectroscopy from the Hubble Space Telescope and the Keck I telescope, we map out the stellar kinematics on both small spatial scales, well within the black hole sphere of influence, and on large scales. We find that the galaxy is rapidly rotating and exhibits a sharp central peak in the velocity dispersion. Using the kinematics and the stellar luminosity density derived from imaging observations, we construct three-integral, orbit-based, triaxial stellar dynamical models. We find the black hole has a mass of M_BH = (8.1_{-1.9}^{+2.0}) x 10^8 M_sun, with an I-band stellar mass-to-light ratio of M/L = 5.0_{-0.4}^{+0.3} M_sun/L_sun (3-sigma uncertainties), and that the intrinsic shape of the galaxy is very round, but oblate. With the work presented here, NGC 3998 is now one of a very small number of galaxies for which both stellar and gas dynamical modeling have been used to measure the mass of the black hole. The stellar dynamical mass is nearly a factor of four larger than the previous gas dynamical black hole mass measurement. Given that this cross-check has so far only been attempted on a few galaxies with mixed results, carrying out similar studies in other objects is essential for quantifying the magnitude and distribution of the cosmic scatter in the black hole mass - host galaxy relations.Comment: 19 pages, 15 figures, accepted for publication in Ap

Observations of Global and Local Infall in NGC 1333

We report ``infall asymmetry'' in the HCO$^+$ (1--0) and (3--2) lines toward NGC 1333, extended over $\sim 0.39 {\rm pc}^2$, a larger extent than has been reported be fore, for any star-forming region. The infall asymmetry extends over a major portion of the star-forming complex, and is not limited to a single protostar, or to a single dense core, or to a single spectral line. It seems likely that the infall asymmetry represents inward motions, and that these motions are physically associated with the complex. Both blue-asymmetric and red-asymmetric lines are seen, but in both the (3--2) and (1--0) lines of HCO$^+$ the vast majority of the asymmetric lines are blue, indicating inward motions. The (3--2) line, tracing denser gas, has the spectra with the strongest asymmetry and these spectra are associated with the protostars IRAS 4A and 4B, which most likely indicates a warm central source is affecting the line profiles. The (3--2) and (1--0) lines usually have the same sense of asymmetry in common positions, but their profiles differ significantly, and the (1--0) line appears to trace motions on much larger spatial scales than does the (3--2) line. Line profile models fit the spectra well, but do not strongly constrain their parameters. The mass accretion rate of the inward motions is of order 10$^{-4}$ M$_\odot$/yr, similar to the ratio of stellar mass to cluster age.Comment: 28 pages, 11 figures, 1 colour figur

Factors influencing utilisation of ‘free-standing’ and ‘alongside’ midwifery units for low-risk births in England: a mixed-methods study

Background Midwifery-led units (MUs) are recommended for ‘low-risk’ births by the National Institute for Health and Care Excellence but according to the National Audit Office were not available in one-quarter of trusts in England in 2013 and, when available, were used by only a minority of the low-risk women for whom they should be suitable. This study explores why. Objectives To map the provision of MUs in England and explore barriers to and facilitators of their development and use; and to ascertain stakeholder views of interventions to address these barriers and facilitators. Design Mixed methods – first, MU access and utilisation across England was mapped; second, local media coverage of the closure of free-standing midwifery units (FMUs) were analysed; third, case studies were undertaken in six sites to explore the barriers and facilitators that have an impact on the development of MUs; and, fourth, by convening a stakeholder workshop, interventions to address the barriers and facilitators were discussed. Setting English NHS maternity services. Participants All trusts with maternity services. Interventions Establishing MUs. Main outcome measures Numbers and types of MUs and utilisation of MUs. Results Births in MUs across England have nearly tripled since 2011, to 15% of all births. However, this increase has occurred almost exclusively in alongside units, numbers of which have doubled. Births in FMUs have stayed the same and these units are more susceptible to closure. One-quarter of trusts in England have no MUs; in those that do, nearly all MUs are underutilised. The study findings indicate that most trust managers, senior midwifery managers and obstetricians do not regard their MU provision as being as important as their obstetric-led unit provision and therefore it does not get embedded as an equal and parallel component in the trust’s overall maternity package of care. The analysis illuminates how provision and utilisation are influenced by a complex range of factors, including the medicalisation of childbirth, financial constraints and institutional norms protecting the status quo. Limitations When undertaking the case studies, we were unable to achieve representativeness across social class in the women’s focus groups and struggled to recruit finance directors for individual interviews. This may affect the transferability of our findings. Conclusions Although there has been an increase in the numbers and utilisation of MUs since 2011, significant obstacles remain to MUs reaching their full potential, especially FMUs. This includes the capacity and willingness of providers to address women’s information needs. If these remain unaddressed at commissioner and provider level, childbearing women’s access to MUs will continue to be restricted. Future work Work is needed on optimum approaches to improve decision-makers’ understanding and use of clinical and economic evidence in service design. Increasing women’s access to information about MUs requires further studies of professionals’ understanding and communication of evidence. The role of FMUs in the context of rural populations needs further evaluation to take into account user and community impact. Funding This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 12. See the NIHR Journals Library website for further project information