3,239 research outputs found
Octonionic Maxwell Equations
An introduction to Quaternions and Octonions is given, and the Maxwell Equations are formulated in terms of each. The conventional, source-free relativistic theory of eight dimensional electromagnetism is introduced and examined. Similarly, the source-free Octonionic Maxwell Equations are developed, and it is shown that the seven dimensional electric and magnetic fields–pure Octonions–each admit plane wave solutions. An Octonionic Faraday tensor is constructed and compared with the conventional Faraday tensor, and it is shown that, in the source-free case, the conventional and Octonionic theories are equivalent
Quaternions, Octonions, and Electromagnetism
An introduction to Quaternions and Octonions is given, and the Maxwell Equations are formulated in terms of each. The conventional, source-free relativistic theory of eight dimensional electromagnetism is introduced and examined. Similarly, the source-free Octonionic Maxwell Equations are developed, and it is shown that the seven dimensional electric and magnetic fields pure Octonions each admit plane wave solutions. An Octonionic Faraday tensor is constructed and compared with the conventional Faraday tensor, and it is shown that, in the source-free case, the conventional and Octonionic theories are equivalent
Expanding the evidence base for the design of policy influencing consumer choice for products and services with environmental impacts: final report
An inordinate fondness for species with intermediate dispersal abilities
J. B. S. Haldane is widely quoted to have quipped that the Creator, if one exists, has an inordinate fondness for beetles. Although Coleoptera may not be the most speciose order once Hymenopteran diversity is fully accounted for, as a whole the very clear differences in species diversity among taxa require an explanation. Here we use stochastic simulations to show that dispersal has eco-evolutionary effects that predict taxa to become particularly species-rich when dispersal is neither too low nor too high. Our model combines recent advances in understanding coexistence in niche space with previously verbally expressed ideas, where too low dispersal imposes biogeographic constraints that prevent a lineage from finding new areas to colonize (reducing opportunities for speciation), while too high dispersal impedes population divergence, leading to few but widely distributed species. We show that this logic holds for species richness and is robust to a variety of model assumptions, but peak diversification rate is instead predicted to increase with dispersal. Our work unifies findings of increasing and decreasing effects of dispersal rate on speciation, and explains why taxa with moderate dispersal abilities have the best prospects for high global species richness.</p
Post hoc analyses of the impact of previous medication on the efficacy of lisdexamfetamine dimesylate in the treatment of attention-deficit/hyperactivity disorder in a randomized, controlled trial
David R Coghill,1 Tobias Banaschewski,2 Michel Lecendreux,3 César Soutullo,4 Alessandro Zuddas,5 Ben Adeyi,6 Shaw Sorooshian7 1Division of Neuroscience, University of Dundee, Dundee, UK; 2Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany; 3Paediatric Sleep Centre and National Reference Centre for Orphan Diseases: Narcolepsy, Idiopathic Hypersomnia and Kleine-Levin Syndrome, Robert-Debré University Hospital, Paris, France; 4Child and Adolescent Psychiatry Unit, Department of Psychiatry and Medical Psychology, University of Navarra Clinic, Pamplona, Spain; 5Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, Cagliari, Italy; 6Shire, Wayne, PA, USA; 7Shire, Eysins, Switzerland Background: Following the approval of lisdexamfetamine dimesylate (LDX) in several European countries for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents with an inadequate response to methylphenidate (MPH) treatment, the aim of the present analysis was to establish the response to LDX in subgroups of patients with different ADHD medication histories. Methods: This was a post hoc subgroup analysis of data from a 7-week, European, double-blind, dose-optimized, Phase III study. Patients aged 6–17 years were randomized 1:1:1 to LDX, placebo, or osmotic-release oral system methylphenidate (OROS-MPH). OROS-MPH was included as a reference arm rather than as a direct comparator. Efficacy was assessed in patients categorized according to their ADHD medication history using the ADHD Rating Scale IV and Clinical Global Impressions-Improvement (CGI-I) scores. Results: The difference between active drug and placebo in least-squares mean change from baseline to endpoint in ADHD Rating Scale IV total score (95% confidence interval) was similar between the overall study population (n=317; LDX, -18.6 [-21.5, -15.7]; OROS- MPH, -13.0 [-15.9, -10.2]) and treatment-naïve individuals (n=147; LDX, -15.1 [-19.4, -10.9]; OROS-MPH, -12.7 [-16.8, -8.5]) or patients previously treated with any ADHD medication (n=170; LDX, -21.5 [-25.5, -17.6]; OROS-MPH, -14.2 [-18.1, -10.3]). In addition, similar proportions of patients receiving active treatment were categorized as improved based on CGI-I score (CGI-I of 1 or 2) in the overall study population and among treatment-naïve individuals or patients previously treated with any ADHD medication. Conclusion: In these post hoc analyses, the response to LDX treatment, and to the reference treatment OROS-MPH, was similar to that observed for the overall study population in subgroups of patients categorized according to whether or not they had previously received ADHD medication. Keywords: attention-deficit/hyperactivity disorder, lisdexamfetamine dimesylate, methylphenidate, central nervous system stimulant
A Wolf in Sheep's Clothing? Patients' and Healthcare Professionals' Perceptions of Oxygen Therapy: An Interpretative Phenomenological Analysis.
Background: Despite emerging evidence and guidelines, poor prescribing and administration of oxygen therapy persists. This study aimed to explore healthcare professionals’ (HCPs) and patients’ perceptions of oxygen. Design: Semi-structured interviews with 28 patients and 34 HCPs. Findings: Three master themes uncovered: oxygen as a panacea, the burden of oxygen, and antecedents to beliefs. Patients used oxygen for breathlessness and as an enabler; they were grateful to oxygen and accepted it as part of the disease. HCPs used oxygen because it helps patients; it works; and it makes HCPs feel better. But oxygen is not benign and a burden is evident with potential antecedents to beliefs revealed. Summary: The findings suggest that a set of fixed beliefs regarding oxygen exist, influenced by several impacting factors. The perception that oxygen is a universal remedy presides, but is, at times, contradictory. These findings will raise awareness of entrenched cultures, influence future educational and research strategies, and inform policy
Destructive leadership: Causes, consequences and countermeasures
In 2010, David Matsuda, an anthropology professor, was asked to study why almost 30 U.S. soldiers in Iraq had committed or attempted suicide in the past year. His investigation showed that while those soldiers often had major problems in their personal lives, the victims also had in common at least one leader (sometimes a couple of leaders) who made their lives hell. While the evidence did not show that the soldiers’ leaders directly caused them to commit or attempt suicide, it did support the notion that the leaders who had made their lives hell had helped to push them over the brink. It was this finding that forced the U.S. military to confront the problem of “toxic” leadership in the army.Full Tex
Characteristics and Performance of Foreign Direct Investment in Retail Trade: The Case of Japanese Firms
In the international business development, foreign direct investment (FDI) as a general phenomenon has been extensively studied, yet the understanding of particular characteristics of FDI in the retail industry remain limited. The success of international retail trade relies heavily on the understanding of consumers in the host countries. Therefore, this paper analyzed the characteristics and performance of foreign direct investment (FDI) in retail trade using the Japanese FDI data (JFDI) from 1986-2001 as a case. We found (1) an overall trend for JFDI to move from the developed countries to developing countries; (2) a modest correlation between subsidiary size and performance; (3) in certain countries/regions, a positive and significant correlation between entry mode and performance; and (4) a focus of JFDI on the USA and the Greater-China area. The results of this paper provide important implications for countries which want the FDI in retail trade and for companies which want to invest in international retail trade
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