Regge trajectories and quarkonium spectrum from a first principle Salpeter equation

We compute the heavy-heavy, light-light and light-heavy quarkonium spectrum starting from a first principle Salpeter equation obtained in a preceding paper. We neglect spin-orbit structures and exclude from our treatment the light pseudoscalar states which in principle would require the use of the full Bethe-Salpeter equation due to the chiral symmetry breaking problem. For the rest we find an overall good agreement with the experimental data. In particular for the light-light case we find straight Regge trajectories with the right slope and intercepts. The strong coupling constant $\alpha_s$, the string tension $\sigma$ occurring in the potential and the heavy quark masses are taken from the heavy quarkonium semirelativistic fit with only a small rearrangement. The light quark masses are set equal to baricentral value of the current quark masses as reported by the particle data group. For what concerns the light-light and the light-heavy systems the calculation is essentially parameter free.Comment: 18 pages, 3 figures, revtex.st

Making Dreams Come True: Parental and Community Involvement in the Rural African American Schools in Burke County, Georgia Between 1930 and 1955

Dreams for the African American child in rural areas of the South between 1930 and 1955 were often short-lived and were tied to the agrarian culture of the time. Cotton was KING and the African Americans were tied to the farm and its products. Crops, with their plantings, cultivations, and gatherings, were the subsistence for the rural African American family. The entire family, parents and children were dependent on the agrarian calendar and its income for support and existence. Children from an early age were required to share the workload in the fields, and they were considered as much a part of the workforce as were their parents. From sun-up to sundown, parents and children worked the red clay furrows of Burke County, Georgia, to find a meager means of livelihood. As sharecroppers or as manual laborers, African Americans were dependent on the landowners (who were white in more cases) for their standard of living. These landowners had African American families tied to the land. Following the Great Depression and the fall of King Cotton caused by the boll weevil, education for African American children was not a realizable dream for most children

Gatekeeper negotiation: Seeking the magic ingredient

One of the biggest obstacles for novice and experienced researchers is the process of negotiating their way into organisations to conduct research. There are many tales of research which has stalled at the gate after promising negotiations with willing partners. This paper draws on preliminary research which seeks to examine gatekeeper negotiations. Early themes of timing, trust, reputation, and personal and professional contacts, are discussed with reference to feedback from participants. It is clearly not just the skill of the researcher in the negotiation process which leads to successful or unsuccessful gatekeeper negotiation outcomes

Enhancing practical skills: Reflections on real case experience

This paper outlines reflections and a short peer evaluation of a live case study approach to a marketing management unit at undergraduate level. The value of a practical case approach for enhancing student skills is highlighted as are some of the lessons learned in the design and delivery of the unit. The paper offers reflections and a peer review which focus on the key elements of the live case. It outlines the adjustments which will be made at the next offering of the unit, and offers insights for others contemplating such projects

Critical friends: Reflections on peer review of teaching

Specific examples of peer reviews of teaching in business disciplines are limited in the literature, yet peer review helps academics improve their teaching practice, develops collegial and collaborative relationships and engenders reflective practice. This paper provides a case study action learning example of a critical friend peer review of teaching practice over one semester. Instead of focussing on standard classroom teaching practice, this peer dialogue differed from more traditional approaches by focussing on those students outside the classroom: external and transnational. An emergent framework for peers to reference in conducting their own peer review of their teaching practice is presented. Limitations in the scope and scale of the review are noted and implications for future peer reviews are discussed

Feature engineering workflow for activity recognition from synchronized inertial measurement units

The ubiquitous availability of wearable sensors is responsible for driving the Internet-of-Things but is also making an impact on sport sciences and precision medicine. While human activity recognition from smartphone data or other types of inertial measurement units (IMU) has evolved to one of the most prominent daily life examples of machine learning, the underlying process of time-series feature engineering still seems to be time-consuming. This lengthy process inhibits the development of IMU-based machine learning applications in sport science and precision medicine. This contribution discusses a feature engineering workflow, which automates the extraction of time-series feature on based on the FRESH algorithm (FeatuRe Extraction based on Scalable Hypothesis tests) to identify statistically significant features from synchronized IMU sensors (IMeasureU Ltd, NZ). The feature engineering workflow has five main steps: time-series engineering, automated time-series feature extraction, optimized feature extraction, fitting of a specialized classifier, and deployment of optimized machine learning pipeline. The workflow is discussed for the case of a user-specific running-walking classification, and the generalization to a multi-user multi-activity classification is demonstrated.Comment: Multi-Sensor for Action and Gesture Recognition (MAGR), ACPR 2019 Workshop, Auckland, New Zealan

Application of Higher-Order Neural Networks to Financial Time-Series Prediction

Financial time series data is characterized by non-linearities, discontinuities and high frequency, multi-polynomial components. Not surprisingly, conventional Artificial Neural Networks (ANNs) have difficulty in modelling such complex data. A more appropriate approach is to apply Higher-Order ANNs, which are capable of extracting higher order polynomial coefficients in the data. Moreover, since there is a one-to-one correspondence between network weights and polynomial coefficients, HONNs (unlike ANNs generally) can be considered open-, rather than 'closed box' solutions, and thus hold more appeal to the financial community. After developing Polynomial and Trigonometric HONNs, we introduce the concept of HONN groups. The latter incorporate piecewise continuous activation functions and thresholds, and as a result are capable of modelling discontinuous (piecewise continuous) data, and what's more to any degree of accuracy. Several other PHONN variants are also described. The performance of P(T)HONNs and HONN groups on representative financial time series is described (credit ratings and exchange rates). In short, HONNs offer roughly twice the performance of MLP/BP on financial time series prediction, and HONN groups around 10% further improvement

Glass transition and alpha-relaxation dynamics of thin films of labeled polystyrene

The glass transition temperature and relaxation dynamics of the segmental motions of thin films of polystyrene labeled with a dye, 4-[N-ethyl-N-(hydroxyethyl)]amino-4-nitraozobenzene (Disperse Red 1, DR1) are investigated using dielectric measurements. The dielectric relaxation strength of the DR1-labeled polystyrene is approximately 65 times larger than that of the unlabeled polystyrene above the glass transition, while there is almost no difference between them below the glass transition. The glass transition temperature of the DR1-labeled polystyrene can be determined as a crossover temperature at which the temperature coefficient of the electric capacitance changes from the value of the glassy state to that of the liquid state. The glass transition temperature of the DR1-labeled polystyrene decreases with decreasing film thickness in a reasonably similar manner to that of the unlabeled polystyrene thin films. The dielectric relaxation spectrum of the DR1-labeled polystyrene is also investigated. As thickness decreases, the $\alpha$-relaxation time becomes smaller and the distribution of the $\alpha$-relaxation times becomes broader. These results show that thin films of DR1-labeled polystyrene are a suitable system for investigating confinement effects of the glass transition dynamics using dielectric relaxation spectroscopy.Comment: 10 pages, 11 figures, 2 Table

An open source approach to medium-term data archiving

Medium- to long-term archiving of digital documents, beyond the lifespan of the authoring software/hardware, is a challenging problem. Magnetic and optical media are susceptible to environmental influences and deteriorate over time, often to the point where the archived documents can no longer be retrieved. Previous attempts to address this problem include migration and emulation, both of which have their attendant difficulties. It is the contention of the present study that an Open Source approach offers several advantages. More specifically, by archiving the Open Source application programs (in source code, not executable form) along with the documents in question, in both plain and compressed form, significantly increases the likelihood of being able to retrieve such archives at some future time. The application source code can be recompiled to a form suitable for reading in (Open Source) viewers, thereby presenting to the user the archived document as the original author envisaged it. One set of experiments was undertaken distributing documents together with their (Open Source) authoring software via a Portable Virtual Machine (PVM) program to unused disk space on a network of SUN workstations. The success of this approach was evaluated using the following four measures: (i) lossiness of conversion, (ii) edit-ability, (iii) ability to save back to the original format, and (iv) functionality retention. Another series of experiments was conducted in which artificial (‘speckle’ or salt-and-pepper) noise was deliberately introduced to the archived documents in order to mimic degradation of the storage medium over time. It was found that survivability was heavily dependent on file type: simple text files and MPEG movies were impervious to even 18% introduced noise. Source code programs and JPEG images, by contrast, were intolerant to even the smallest noise levels (it has to be said however that straightforward re-editing of the former led to error-free compilation without much difficulty). Lastly, it was found that decompression (specifically the publicly available RAR decompressor) further enhanced the file recovery process. We conclude that an Open Source approach to the preservation of digital archives has considerable potential

Alterations to the Gastrointestinal Microbiome Associated with Methamphetamine Use among Young Men who have Sex with Men.

Methamphetamine (MA) use is a major public health problem in the United States, especially among people living with HIV (PLWH). Many MA-induced neurotoxic effects are mediated by inflammation and gut microbiota may play a role in this process, yet the effects of MA on the microbiome have not been adequately explored. Therefore, we performed 16S rRNA gene sequencing on rectal swab samples from 381 men who have sex with men, 48% of whom were PLWH and 41% of whom used MA. We compared microbiome composition between MA users and non-users while testing for potential interactions with HIV and controlling for numerous confounders using inverse probability of treatment weighting. We found that MA use explained significant variation in overall composition (R2 = 0.005, p = 0.008) and was associated with elevated Finegoldia, Parvimonas, Peptoniphilus, and Porphyromonas and reduced Butyricicoccus and Faecalibacterium, among others. Genera including Actinomyces and Streptobacillus interacted with HIV status, such that they were increased in HIV+ MA users. Finegoldia and Peptoniphilus increased with increasing frequency of MA use, among others. In summary, MA use was associated with a microbial imbalance favoring pro-inflammatory bacteria, including some with neuroactive potential and others that have previously been associated with poor HIV outcomes