Solving the Klein-Gordon equation using Fourier spectral methods: A benchmark test for computer performance

The cubic Klein-Gordon equation is a simple but non-trivial partial differential equation whose numerical solution has the main building blocks required for the solution of many other partial differential equations. In this study, the library 2DECOMP&FFT is used in a Fourier spectral scheme to solve the Klein-Gordon equation and strong scaling of the code is examined on thirteen different machines for a problem size of 512^3. The results are useful in assessing likely performance of other parallel fast Fourier transform based programs for solving partial differential equations. The problem is chosen to be large enough to solve on a workstation, yet also of interest to solve quickly on a supercomputer, in particular for parametric studies. Unlike other high performance computing benchmarks, for this problem size, the time to solution will not be improved by simply building a bigger supercomputer.Comment: 10 page

Automated pathway and reaction prediction facilitates in silico identification of unknown metabolites in human cohort studies

Identification of metabolites in non-targeted metabolomics continues to be a bottleneck in metabolomics studies in large human cohorts. Unidentified metabolites frequently emerge in the results of association studies linking metabolite levels to, for example, clinical phenotypes. For further analyses these unknown metabolites must be identified. Current approaches utilize chemical information, such as spectral details and fragmentation characteristics to determine components of unknown metabolites. Here, we propose a systems biology model exploiting the internal correlation structure of metabolite levels in combination with existing biochemical and genetic information to characterize properties of unknown molecules. Levels of 758 metabolites (439 known, 319 unknown) in human blood samples of 2279 subjects were measured using a non-targeted metabolomics platform (LC-MS and GC-MS). We reconstructed the structure of biochemical pathways that are imprinted in these metabolomics data by building an empirical network model based on 1040 significant partial correlations between metabolites. We further added associations of these metabolites to 134 genes from genome-wide association studies as well as reactions and functional relations to genes from the public database Recon 2 to the network model. From the local neighborhood in the network, we were able to predict the pathway annotation of 180 unknown metabolites. Furthermore, we classified 100 pairs of known and unknown and 45 pairs of unknown metabolites to 21 types of reactions based on their mass differences. As a proof of concept, we then looked further into the special case of predicted dehydrogenation reactions leading us to the selection of 39 candidate molecules for 5 unknown metabolites. Finally, we could verify 2 of those candidates by applying LC-MS analyses of commercially available candidate substances. The formerly unknown metabolites X-13891 and X-13069 were shown to be 2-dodecendioic acid and 9-tetradecenoic acid, respectively. Our data-driven approach based on measured metabolite levels and genetic associations as well as information from public resources can be used alone or together with methods utilizing spectral patterns as a complementary, automated and powerful method to characterize unknown metabolites

On the Vanishing Displacement Current Limit for Time-Harmonic Maxwell Equations

This paper considers a transmission boundary-value problem for the time-harmonic Maxwell equations neglecting displacement currents which is frequently used for the numerical computation of eddy-currents. Across material boundaries the tangential components of the magnetic field H and the normal component of the magnetization müH are assumed to be continuous. this problem admits a hyperplane of solutions if the domains under consideration are multiply connected. Using integral equation methods and singular perturbation theory it is shown that this hyperplane contains a unique point which is the limit of the classical electromagnetic transmission boundary-value problem for vanishing displacement currents. Considering the convergence proof, a simple contructive criterion how to select this solution is immediately derived

On the Vanishing Displacement Current Limit for Time-Harmonic Maxwell Equations

This paper considers a transmission boundary-value problem for the time-harmonic Maxwell equations neglecting displacement currents which is frequently used for the numerical computation of eddy-currents. Across material boundaries the tangential components of the magnetic field H and the normal component of the magnetization müH are assumed to be continuous. this problem admits a hyperplane of solutions if the domains under consideration are multiply connected. Using integral equation methods and singular perturbation theory it is shown that this hyperplane contains a unique point which is the limit of the classical electromagnetic transmission boundary-value problem for vanishing displacement currents. Considering the convergence proof, a simple contructive criterion how to select this solution is immediately derived

Past, present, and future trends of master\u27s education in nursing

Nurses interested in pursuing careers in advanced practice are now being educated at the doctoral level through new Doctorate of Nursing Practice (DNP) degree programs. In light of this shift , master’s programs for advanced practice nurses are in a tenuous position, and it is questionable whether the remaining master’s level educational programs are meeting the needs of consumers, healthcare institutions and students. Given the great need for clinical leadership in healthcare, it is essential to re-examine master’s nursing education to ensure that educational institutions are meeting the needs of graduate nursing students, consumers and health care systems. Research supports that the master’s prepared nurse of the future must be proficient in the development and management of accountable care systems using state-of-the-art technology. In addition, interprofessional models show to improvement in health care delivery and health outcomes. The current demands in healthcare that impact nursing education will be discussed, including the movement toward interprofessional education and the broadened expertise, required of master’s prepared nurses working in an era of healthcare reform. While cademic medical centers are actively advancing toward an interprofessional model, the majority of nurses in this country are educated in private and community settings. This article will examine the move toward interprofessional education at a private university, utilizing clinical partnerships to a revise the master’s program. The goal of this revision is to empower students with the expertise required in today’s healthcare environment to improve the delivery of care. The recent Institute of Medicine report on the Future of Nursing states that nurses must achieve higher levels of education and training in response to … “increasing [healthcare] demands” (IOM, 2010, p. 2). This statement comes at a pivotal time in nursing education. Nurses interested in pursuing careers in advanced practice are now being educated at the doctoral level through new Doctorate of Nursing Practice (DNP) degree programs. In light of this shift, master’s programs in nursing are in a tenuous position, and it is questionable whether the remaining master’s level educational programs (healthcare management, nursing education and clinical nurse leader [CNL]) are meeting the needs of consumers, healthcare institutions and students. The 2008 RN Survey conducted by the Bureau of Health Professions indicated that 19.2 percent of RNs who earned a masters degree enrolled in programs with a focus in administration, business, or management, 13.3 percent focused on education, and 5.9 percent earned Public Health degrees (Bureau of Health Professions, 2010). Dr. Patricia S. Yoder-Wise, President of the Council on Graduate Education for Administration of Nursing, summarized the situation by stating, “ the absence of a nursing master’s option could have unintended consequences of moving nurses in leadership roles to other fields to secure a master’s degree. This further dilutes the knowledge needed to be highly effective in leading and managing the nursing team.” She further states that “eliminating the master’s in nursing as part of the education progression could be counterproductive to patients and the profession” (Yoder-Wise, 2011, p. 258). Given the great need for clinical leadership in healthcare, it is essential to re-examine master’s nursing education to ensure that educational institutions are meeting the needs of graduate nursing students, consumers and health care systems. Globally, there is a strong call for developing models of interprofessional education and practice. Research supports that interprofessional models will lead to improvements in health care delivery and health outcomes (IPEC, 2011). The purpose of this article is to review master’s education in nursing from the past to present, to enhance understanding of the various types of educational programs that have developed over time, and how society has influenced this development. The current demands in healthcare with potential to impact nursing education will be discussed, including the movement toward interprofessional education and the broadened expertise expectedof master’s prepared nurses working in an era of healthcare reform. Based on the educationalhistory and the current needs of nurses in the present healthcare environment, the future of master\u27s nursing education will be envisioned. The article concludes by presenting one curricular model for a Master’s in nursing program that meets the need for highly skilled nurse leaders in the 21st century

Solvent-dependent facile synthesis of diaryl selenides and biphenols employing selenium dioxide

Biphenols are important structure motifs for ligand systems in organic catalysis and are therefore included in the category of so-called “privileged ligands”. We have developed a new synthetic pathway to construct these structures by the use of selenium dioxide, a stable, powerful, and commercially available oxidizer. Our new, and easy to perform protocol gives rise to biphenols and diaryl selenides depending on the solvent employed. Oxidative treatment of phenols in acetic acid yields the corresponding biphenols, whereas conversion in pyridine results in the preferred formation of diaryl selenides. As a consequence, we were able to isolate a broad scope of novel diaryl selenides, which could act as pincer-like ligands with further applications in organic synthesis or as ligands in transition metal catalysis

Beer Brewing and the Environmental Engineer: Tapping into Experiential Learning

Second to water, beer may perhaps be the next most desirable beverage in the lives of countless environmental engineering students. But do they fully understand or appreciate the engineering and scientific principles behind beer making? While considerable effort has been put forth in academia to teach and explain the critical environmental process of fermentation, too many students are limited to examples and explanations contained within a course textbook. The United States Military Academy is committed to providing experiential learning opportunities that reach beyond traditional classroom instruction. Our Environmental Biological Systems Course (EV396) offers an opportunity for environmental engineers to achieve a deeper, more practical understanding and appreciation for biological systems within our environment. As part of the experiential learning process, EV396 requires students to successfully brew beer in a laboratory setting to enhance their understanding of microbial metabolic processes, disinfection principles, and aseptic techniques. This paper aims to highlight and explain the linkage between the complex process of alcoholic fermentation involved in beer brewing to the environmental engineering practice. Indeed, environmental engineers often face challenges where they must design and operate biological systems and apply engineering concepts like those integral to brewing beer, including conventional wastewater management, microbial fuel cells, hazardous waste treatment and remediation, slow sand filtration, and disinfection. As part of this fermentation laboratory experience, students select the style of beer they wish to brew and exercise the engineered techniques required to brew a safe and refreshing product. Additionally, students are required to submit a detailed report demonstrating their ability to identify and evaluate key physiochemical and biochemical engineering processes. Calculations involve fermentation efficacy, specific gravity and yield, theoretical and actual ethanol content, and scaling from bench experiments to commercial production. The laboratory familiarizes students with engineering concepts, including substrates that serve as carbon and energy sources, methods for creating anaerobic reactors, and solid-liquid separation processes. Using the 5-point Likert scale, with 5 indicating greatest achievement, student laboratory performance scores are consistently greater than 3 and many are above 4, indicating effective learning, application, and understanding. Historical assessment and evaluation of how well this experiential learning laboratory supports course objectives and ABET Student Outcomes and Program Criteria are discussed in detail