Mentoring to Grow Library Leaders

Article discussing mentoring and growing library leaders

Visualising the past – an evaluation of processes and sequences for fingermark recovery from old documents

This study aimed to collect data on the effectiveness of most of the fingermark visualisation reagents currently used on porous surfaces on fingermarks aged for up to 90 years, significantly extending the timescales for which such information exists. A limited subset of the variables associated with processing of old fingermarks was explored, with a focus on the use of 1,8 diazafluoren-9-one (DFO), 1,2-indandione, ninhydrin, and physical developer. These techniques were used in sequence on batches of cheques between 11 and 32 years old, and on documents dating from the 1920s and 1940s. The potential for applying a physical developer enhancement process (blue toning) as the final step in the sequence was also explored. The benefits of using processing sequences on porous items were clearly demonstrated, with all processes in the sequence adding value in terms of additional marks found on the cheques up to 32 years old. In addition, physical developer was found to be capable of developing fingermarks up to 90 years old, whereas the amino acid reagents appear less effective on documents of 70 years and older. An experimental physical developer formulation with reduced environmental impact was found to be as effective as the existing process in these experiments. Blue toning was found to visualise an additional 10-25% of marks, and its wider use after silver-based deposition processes is recommended based on the evidence from this study.Peer reviewedFinal Accepted Versio

Incoherent dynamics in neutron-matter interaction

Coherent and incoherent neutron-matter interaction is studied inside a recently introduced approach to subdynamics of a macrosystem. The equation describing the interaction is of the Lindblad type and using the Fermi pseudopotential we show that the commutator term is an optical potential leading to well-known relations in neutron optics. The other terms, usually ignored in optical descriptions and linked to the dynamic structure function of the medium, give an incoherent contribution to the dynamics, which keeps diffuse scattering and attenuation of the coherent beam into account, thus warranting fulfilment of the optical theorem. The relevance of this analysis to experiments in neutron interferometry is briefly discussed.Comment: 15 pages, revtex, no figures, to appear in Phys. Rev.

Microbes, Microbiota, and Colon Cancer

Colorectal cancer (CRC) presents a considerable disease burden worldwide. The human colon is also an anatomical location with the largest number of microbes. It is natural, therefore, to anticipate a role for microbes, particularly bacteria, in colorectal carcinogenesis. The increasing accessibility of microbial meta’omics is fueling a surge in our understanding of the role that microbes and the microbiota play in CRC. In this review, we will discuss recent insights into contributions of the microbiota to CRC and explore conceptual frameworks for evaluating the role of microbes in cancer causation. We also highlight new findings on candidate CRC-potentiating species and current knowledge gaps. Finally, we explore the roles of microbial metabolism as it relates to bile acids, xenobiotics, and diet in the etiology and therapeutics of CRC

“If You Are Old Enough to Die for Your Country, You Should Be Able to Get a Pinch of Snuff”: Views of Tobacco 21 Among Appalachian Youth

Background: Multiple strategies have been utilized in attempts to decrease the prevalence of youth tobacco use. One strategy, raising the minimum legal sale age (MLSA) of tobacco products to 21, known as Tobacco 21, has recently gained popularity. Tobacco 21 legislation targets youth tobacco use by obstructing two main sources of youth tobacco products: stores and older friends. Although these sources are the most common for youth across the nation, regional differences have not been explored. Further, youth perspectives about raising the tobacco MLSA have not been considered. Youth may help identify potential challenges to implementing tobacco control measures, as well as suggest alternatives for intervention, thus helping to shape successful tobacco control policies. Study Aim: This study aimed to 1) examine youth perspectives on raising the tobacco minimum legal sale age to 21 and 2) identify common sources of tobacco products among middle and high school students living in rural, low-income Appalachian communities. Methods: A cross-sectional survey about perceptions and use of tobacco products was conducted with students in the Appalachian regions of Kentucky and North Carolina (N=426). Questions were asked concerning perspectives on the effect of Tobacco 21 implementation. Descriptive statistics characterized participants by Tobacco 21 perspectives. Participants were given the opportunity to further expand upon their opinions in an open-ended format. Results: The majority (58.7%) of participants responded that the same number of youth would use tobacco if the legal purchase age were raised, followed by responses that fewer would use (28.9%) and more would use (12.4%). Significant differences emerged based on tobacco use status (p\u3c.05), friends’ tobacco use (p\u3c.001), and whether participants identified family members as sources of youth tobacco products (p=.047). When given the opportunity to expand upon their views concerning the implementation of Tobacco 21 laws in their communities, many respondents cited poor enforcement of tobacco MLSAs at stores, continued access to tobacco products from family members and friends, and the overall abundance of tobacco in their communities as potential barriers to the successful implementation. Conclusion: Fewer than one-third of participants believed that Tobacco 21 legislation would succeed in reducing the prevalence of youth tobacco use. Perspectives on the effect of Tobacco 21 legislation were related to personal tobacco use, exposure to tobacco users, and beliefs that family members provide tobacco products to youth. Open-ended responses identify potential obstacles in implementing Tobacco 21 legislation in Appalachia. Future research should attempt to include youth perspectives when designing and implementing tobacco control policies and examine family members as sources of tobacco products for youth

Observer with a constant proper acceleration

Relying on the equivalence principle, a first approach of the general theory of relativity is presented using the spacetime metric of an observer with a constant proper acceleration. Within this non inertial frame, the equation of motion of a freely moving object is studied and the equation of motion of a second accelerated observer with the same proper acceleration is examined. A comparison of the metric of the accelerated observer with the metric due to a gravitational field is also performed.Comment: 5 figure

Nuclear Incompressibility in Asymmetric Systems at Finite Temperature and Entropy

The nuclear incompressibility $\kappa$ is investigated in asymmetric systems in a mean field model. The calculations are done at zero and finite temperatures and include surface, Coulomb and symmetry energy terms for several equations of state. Also considered is the behavior of the incompressibility at constant entropy $kappa_Q$ which is shown to have a very different behavior than the isothermal $kappa$. Namely, $kappa_Q$ decreases with increasing entropy while the isothermal $kappa$ increases with increasing $T$. A duality is found between the adiabatic $kappa_Q$ and the T=0 isothermal $kappa$. Analytic and also simple approximate expressions for $kappa$ are given.Comment: 11 page

Using state space differential geometry for nonlinear blind source separation

Given a time series of multicomponent measurements of an evolving stimulus, nonlinear blind source separation (BSS) seeks to find a "source" time series, comprised of statistically independent combinations of the measured components. In this paper, we seek a source time series with local velocity cross correlations that vanish everywhere in stimulus state space. However, in an earlier paper the local velocity correlation matrix was shown to constitute a metric on state space. Therefore, nonlinear BSS maps onto a problem of differential geometry: given the metric observed in the measurement coordinate system, find another coordinate system in which the metric is diagonal everywhere. We show how to determine if the observed data are separable in this way, and, if they are, we show how to construct the required transformation to the source coordinate system, which is essentially unique except for an unknown rotation that can be found by applying the methods of linear BSS. Thus, the proposed technique solves nonlinear BSS in many situations or, at least, reduces it to linear BSS, without the use of probabilistic, parametric, or iterative procedures. This paper also describes a generalization of this methodology that performs nonlinear independent subspace separation. In every case, the resulting decomposition of the observed data is an intrinsic property of the stimulus' evolution in the sense that it does not depend on the way the observer chooses to view it (e.g., the choice of the observing machine's sensors). In other words, the decomposition is a property of the evolution of the "real" stimulus that is "out there" broadcasting energy to the observer. The technique is illustrated with analytic and numerical examples.Comment: Contains 14 pages and 3 figures. For related papers, see http://www.geocities.com/dlevin2001/ . New version is identical to original version except for URL in the bylin

ACE Data from the ACE Science Center

The purpose of the ACE Science Center (ASC) is to perform level 1 processing of data from the nine science instruments aboard the Advanced Composition Explorer (ACE) spacecraft and to facilitate access to all ACE data by both the instrument investigators and the space physics community. We describe the ACE data products available from the ASC and the methods by which users may access the data

Effects of Process Variables and Size Scale on Solidification Microstructure in Laser-Based Solid Freeform Fabrication of Ti-6Al-4V

Mechanical Engineerin