Non-invasive anaerobic threshold measurement using fuzzy model interpolation

The interface between skeletal muscle activation through aerobic and anaerobic glycolysis is of key interest to sportspeople and athletes who participate in medium to long distance sports, such as middle- and long-distance running, cycling, swimming, rowing, kayaking and a variety of other events. To date, the gold standard for measuring anaerobic threshold (AT) is a structured test to exhaustion where blood lactate concentration is measured at regular intervals. However, the need for invasive testing, requiring trained personnel and specialist equipment, limits the availability of such tests. This paper proposes a non-invasive AT measurement method, which validates well against AT measured using lactate analysis. In addition, the proposed test has a relatively loose set of requirements on the exercise test protocol required and just requires a measure of exercise intensity and heart-rate. While the test is applicable to a range of sports, usage is demonstrated in this paper for a set of cyclists, using velocity as a measure of exercise intensity

Surface structure and solidification morphology of aluminum nanoclusters

Classical molecular dynamics simulation with embedded atom method potential had been performed to investigate the surface structure and solidification morphology of aluminum nanoclusters Aln (n = 256, 604, 1220 and 2048). It is found that Al cluster surfaces are comprised of (111) and (001) crystal planes. (110) crystal plane is not found on Al cluster surfaces in our simulation. On the surfaces of smaller Al clusters (n = 256 and 604), (111) crystal planes are dominant. On larger Al clusters (n = 1220 and 2048), (111) planes are still dominant but (001) planes can not be neglected. Atomic density on cluster (111)/(001) surface is smaller/larger than the corresponding value on bulk surface. Computational analysis on total surface area and surface energies indicates that the total surface energy of an ideal Al nanocluster has the minimum value when (001) planes occupy 25% of the total surface area. We predict that a melted Al cluster will be a truncated octahedron after equilibrium solidification.Comment: 22 pages, 6 figures, 34 reference

Combining mirtazapine with SSRIs or SNRIs for treatment-resistant depression: The MIR RCT

Background: Depression is usually managed in primary care and antidepressants are often the first-line treatment, but only half of those treated respond to a single antidepressant. Objectives: To investigate whether or not combining mirtazapine with serotonin–noradrenaline reuptake inhibitor (SNRI) or selective serotonin reuptake inhibitor (SSRI) antidepressants results in better patient outcomes and more efficient NHS care than SNRI or SSRI therapy alone in treatment-resistant depression (TRD). Design: The MIR trial was a two-parallel-group, multicentre, pragmatic, placebo-controlled randomized trial with allocation at the level of the individual. Setting: Participants were recruited from primary care in Bristol, Exeter, Hull/York and Manchester/Keele. Participants: Eligible participants were aged ≥ 18 years; were taking a SSRI or a SNRI antidepressant for at least 6 weeks at an adequate dose; scored ≥ 14 points on the Beck Depression Inventory-II (BDI-II); were adherent to medication; and met the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, criteria for depression. Interventions: Participants were randomised using a computer-generated code to either oral mirtazapine or a matched placebo, starting at a dose of 15 mg daily for 2 weeks and increasing to 30 mg daily for up to 12 months, in addition to their usual antidepressant. Participants, their general practitioners (GPs) and the research team were blind to the allocation. Main outcome measures: The primary outcome was depression symptoms at 12 weeks post randomization compared with baseline, measured as a continuous variable using the BDI-II. Secondary outcomes (at 12, 24 and 52 weeks) included response, remission of depression, change in anxiety symptoms, adverse events (AEs), quality of life, adherence to medication, health and social care use and cost-effectiveness. Outcomes were analysed on an intention-to-treat basis. A qualitative study explored patients’ views and experiences of managing depression and GPs’ views on prescribing a second antidepressant. Results: There were 480 patients randomised to the trial (mirtazapine and usual care, n = 241; placebo and usual care, n = 239), of whom 431 patients (89.8%) were followed up at 12 weeks. BDI-II scores at 12 weeks were lower in the mirtazapine group than the placebo group after adjustment for baseline BDI-II score and minimisation and stratification variables [difference –1.83 points, 95% confidence interval (CI) –3.92 to 0.27 points; p = 0.087]. This was smaller than the minimum clinically important difference and the CI included the null. The difference became smaller at subsequent time points (24 weeks: –0.85 points, 95% CI –3.12 to 1.43 points; 12 months: 0.17 points, 95% CI –2.13 to 2.46 points). More participants in the mirtazapine group withdrew from the trial medication, citing mild AEs (46 vs. 9 participants). Conclusions: This study did not find convincing evidence of a clinically important benefit for mirtazapine in addition to a SSRI or a SNRI antidepressant over placebo in primary care patients with TRD. There was no evidence that the addition of mirtazapine was a cost-effective use of NHS resources. GPs and patients were concerned about adding an additional antidepressant. Limitations: Voluntary unblinding for participants after the primary outcome at 12 weeks made interpretation of longer-term outcomes more difficult. Future work: Treatment-resistant depression remains an area of important, unmet need, with limited evidence of effective treatments. Promising interventions include augmentation with atypical antipsychotics and treatment using transcranial magnetic stimulation

Combining mirtazapine with SSRIs or SNRIs for treatment-resistant depression : the MIR RCT

BACKGROUND: Depression is usually managed in primary care and antidepressants are often the first-line treatment, but only half of those treated respond to a single antidepressant. OBJECTIVES: To investigate whether or not combining mirtazapine with serotonin-noradrenaline reuptake inhibitor (SNRI) or selective serotonin reuptake inhibitor (SSRI) antidepressants results in better patient outcomes and more efficient NHS care than SNRI or SSRI therapy alone in treatment-resistant depression (TRD). DESIGN: The MIR trial was a two-parallel-group, multicentre, pragmatic, placebo-controlled randomised trial with allocation at the level of the individual. SETTING: Participants were recruited from primary care in Bristol, Exeter, Hull/York and Manchester/Keele. PARTICIPANTS: Eligible participants were aged ≥ 18 years; were taking a SSRI or a SNRI antidepressant for at least 6 weeks at an adequate dose; scored ≥ 14 points on the Beck Depression Inventory-II (BDI-II); were adherent to medication; and met the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, criteria for depression. INTERVENTIONS: Participants were randomised using a computer-generated code to either oral mirtazapine or a matched placebo, starting at a dose of 15 mg daily for 2 weeks and increasing to 30 mg daily for up to 12 months, in addition to their usual antidepressant. Participants, their general practitioners (GPs) and the research team were blind to the allocation. MAIN OUTCOME MEASURES: The primary outcome was depression symptoms at 12 weeks post randomisation compared with baseline, measured as a continuous variable using the BDI-II. Secondary outcomes (at 12, 24 and 52 weeks) included response, remission of depression, change in anxiety symptoms, adverse events (AEs), quality of life, adherence to medication, health and social care use and cost-effectiveness. Outcomes were analysed on an intention-to-treat basis. A qualitative study explored patients' views and experiences of managing depression and GPs' views on prescribing a second antidepressant. RESULTS: There were 480 patients randomised to the trial (mirtazapine and usual care, n = 241; placebo and usual care, n = 239), of whom 431 patients (89.8%) were followed up at 12 weeks. BDI-II scores at 12 weeks were lower in the mirtazapine group than the placebo group after adjustment for baseline BDI-II score and minimisation and stratification variables [difference -1.83 points, 95% confidence interval (CI) -3.92 to 0.27 points; p = 0.087]. This was smaller than the minimum clinically important difference and the CI included the null. The difference became smaller at subsequent time points (24 weeks: -0.85 points, 95% CI -3.12 to 1.43 points; 12 months: 0.17 points, 95% CI -2.13 to 2.46 points). More participants in the mirtazapine group withdrew from the trial medication, citing mild AEs (46 vs. 9 participants). CONCLUSIONS: This study did not find convincing evidence of a clinically important benefit for mirtazapine in addition to a SSRI or a SNRI antidepressant over placebo in primary care patients with TRD. There was no evidence that the addition of mirtazapine was a cost-effective use of NHS resources. GPs and patients were concerned about adding an additional antidepressant. LIMITATIONS: Voluntary unblinding for participants after the primary outcome at 12 weeks made interpretation of longer-term outcomes more difficult. FUTURE WORK: Treatment-resistant depression remains an area of important, unmet need, with limited evidence of effective treatments. Promising interventions include augmentation with atypical antipsychotics and treatment using transcranial magnetic stimulation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN06653773; EudraCT number 2012-000090-23. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 63. See the NIHR Journals Library website for further project information

Dissociable Influences of Auditory Object vs. Spatial Attention on Visual System Oscillatory Activity

Given that both auditory and visual systems have anatomically separate object identification (“what”) and spatial (“where”) pathways, it is of interest whether attention-driven cross-sensory modulations occur separately within these feature domains. Here, we investigated how auditory “what” vs. “where” attention tasks modulate activity in visual pathways using cortically constrained source estimates of magnetoencephalograpic (MEG) oscillatory activity. In the absence of visual stimuli or tasks, subjects were presented with a sequence of auditory-stimulus pairs and instructed to selectively attend to phonetic (“what”) vs. spatial (“where”) aspects of these sounds, or to listen passively. To investigate sustained modulatory effects, oscillatory power was estimated from time periods between sound-pair presentations. In comparison to attention to sound locations, phonetic auditory attention was associated with stronger alpha (7–13 Hz) power in several visual areas (primary visual cortex; lingual, fusiform, and inferior temporal gyri, lateral occipital cortex), as well as in higher-order visual/multisensory areas including lateral/medial parietal and retrosplenial cortices. Region-of-interest (ROI) analyses of dynamic changes, from which the sustained effects had been removed, suggested further power increases during Attend Phoneme vs. Location centered at the alpha range 400–600 ms after the onset of second sound of each stimulus pair. These results suggest distinct modulations of visual system oscillatory activity during auditory attention to sound object identity (“what”) vs. sound location (“where”). The alpha modulations could be interpreted to reflect enhanced crossmodal inhibition of feature-specific visual pathways and adjacent audiovisual association areas during “what” vs. “where” auditory attention

Rare Variants in Ischemic Stroke: An Exome Pilot Study

The genetic architecture of ischemic stroke is complex and is likely to include rare or low frequency variants with high penetrance and large effect sizes. Such variants are likely to provide important insights into disease pathogenesis compared to common variants with small effect sizes. Because a significant portion of human functional variation may derive from the protein-coding portion of genes we undertook a pilot study to identify variation across the human exome (i.e., the coding exons across the entire human genome) in 10 ischemic stroke cases. Our efforts focused on evaluating the feasibility and identifying the difficulties in this type of research as it applies to ischemic stroke. The cases included 8 African-Americans and 2 Caucasians selected on the basis of similar stroke subtypes and by implementing a case selection algorithm that emphasized the genetic contribution of stroke risk. Following construction of paired-end sequencing libraries, all predicted human exons in each sample were captured and sequenced. Sequencing generated an average of 25.5 million read pairs (75 bp×2) and 3.8 Gbp per sample. After passing quality filters, screening the exomes against dbSNP demonstrated an average of 2839 novel SNPs among African-Americans and 1105 among Caucasians. In an aggregate analysis, 48 genes were identified to have at least one rare variant across all stroke cases. One gene, CSN3, identified by screening our prior GWAS results in conjunction with our exome results, was found to contain an interesting coding polymorphism as well as containing excess rare variation as compared with the other genes evaluated. In conclusion, while rare coding variants may predispose to the risk of ischemic stroke, this fact has yet to be definitively proven. Our study demonstrates the complexities of such research and highlights that while exome data can be obtained, the optimal analytical methods have yet to be determined

Structural matters in HTSC; the origin and form of stripe organization and checker boarding

The paper deals with the controversial charge and spin self-organization phenomena in the HTSC cuprates, of which neutron, X-ray, STM and ARPES experiments give complementary, sometimes apparently contradictory glimpses. The examination has been set in the context of the boson-fermion, negative-U understanding of HTSC advocated over many years by the author. Stripe models are developed which are 2q in nature and diagonal in form. For such a geometry to be compatible with the data rests upon both the spin and charge arrays being face-centred. Various special doping concentrations are closely looked at, in particular p = 0.1836 or 9/49, which is associated with the maximization of the superconducting condensation energy and the termination of the pseudogap regime. The stripe models are dictated by real space organization of the holes, whereas the dispersionless checkerboarding is interpreted in terms of correlation driven collapse of normal Fermi surface behaviour and response functions. The incommensurate spin diffraction below the resonance energy is seen as in no way expressing spin-wave physics or Fermi surface nesting, but is driven by charge and strain (Jahn-Teller) considerations, and it stands virtually without dispersion. The apparent dispersion comes from the downward dispersion of the resonance peak, and the growth of a further incoherent commensurate peak ensuing from the falling level of charge stripe organization under excitation.Comment: 49 pages with 8 figure