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Surface-enhanced Raman spectroscopy (SERS) is a potential fast and inexpensive method of analyte quantification, which can be combined with deep learning to discover biomarker-disease relationships. This study aims to address present challenges of SERS through a novel SERS bio-quantification framework, including spectral processing, analyte quantification, and model explainability. To this end,serotonin quantification in urine media was assessed as a model task with 682 SERS spectra measured in a micromolar range using cucurbit[8]uril chemical spacers. A denoising autoencoder was utilized for spectral enhancement, and convolutional neural networks (CNN) and vision transformers were utilized for biomarker quantification. Lastly, a novel context representative interpretable model explanations (CRIME) method was developed to suit the current needs of SERS mixture analysis explainability. Serotonin quantification was most efficient in denoised spectra analysed using a convolutional neural network with a three-parameter logistic output layer (mean absolute error = 0.15 {\mu}M, mean percentage error = 4.67%). Subsequently, the CRIME method revealed the CNN model to present six prediction contexts, of which three were associated with serotonin. The proposed framework could unlock a novel, untargeted hypothesis generating method of biomarker discovery considering the rapid and inexpensive nature of SERS measurements, and the potential to identify biomarkers from CRIME contexts.

In real-world elections where voters cast preference ballots, voters often provide only a partial ranking of the candidates. Despite this empirical reality, prior social choice literature frequently analyzes fairness criteria under the assumption that all voters provide a complete ranking of the candidates. We introduce new fairness criteria for multiwinner ranked-choice elections concerning truncated ballots. In particular, we define notions of the independence of losing voters blocs and independence of winning voters blocs, which state that the winning committee of an election should not change when we remove partial ballots which rank only losing candidates, and the winning committee should change in reasonable ways when removing ballots which rank only winning candidates. Of the voting methods we analyze, the Chamberlin-Courant rule performs the best with respect to these criteria, the expanding approvals rule performs the worst, and the method of single transferable vote falls in between.

We analyze a type of voting paradox which we term an involvement paradox, in which a candidate who loses an election could be made into a winner if more of the candidate's non-supporters participated in the election, or a winner could be made into a loser if more of the candidate's supporters participated. Such paradoxical outcomes are possible under the voting method of single transferable vote (STV), which is widely used for political elections throughout the world. We provide a worst-case analysis of involvement paradoxes under STV and show several interesting examples of these paradoxes from elections in Scotland., Comment: This will appear, in slightly modified form, in an upcoming issue of Mathematics Magazine

In this paper, we provide theoretical and empirical estimates for the likelihood of a negative participation paradox under instant runoff voting in three-candidate elections. We determine the probability of the paradox and related conditional probabilities based on the impartial anonymous culture and impartial culture models for both complete and partial ballots. We compare these results to the empirical likelihood of a negative participation paradox occurring under instant runoff voting in a large database of voter profiles which have been reduced to three candidates. Lastly, we analyze the relative likelihood of this paradox in comparison to other well-known paradoxes.

In the popular debate over the use of ranked-choice voting, it is often claimed that the method of single transferable vote (STV) is immune or mostly immune to the so-called ``spoiler effect,'' where the removal of a losing candidate changes the set of winners. This claim has previously been studied only in the single-winner case. We investigate how susceptible STV is to the spoiler effect in multiwinner elections, where the output of the voting method is a committee of size at least two. To evaluate STV we compare it to numerous other voting methods including single non-transferable vote, $k$-Borda, and the Chamberlin-Courant rule. We provide simulation results under three different random models and empirical results using a large database of real-world multiwinner political elections from Scotland. Our results show that STV is not spoiler-proof in any meaningful sense in the multiwinner context, but it tends to perform well relative to other methods, especially when using real-world ballot data.

Effective field theories (EFTs) of heavy particles coupled to the inflaton are rife with operator redundancies, frequently obscured by sensitivity to both boundary terms and field redefinitions. We initiate a systematic study of these redundancies by establishing a minimal operator basis for an archetypal example, the abelian gauge-Higgs-inflaton EFT. Working up to dimension 9, we show that certain low-dimensional operators are entirely redundant and identify new non-redundant operators with potentially interesting cosmological collider signals. Our methods generalize straightforwardly to other EFTs of heavy particles coupled to the inflaton., Comment: 31 pages, 4 figures

We analyze a little-known property of apportionment methods that captures how allocations scale with the size of the house: specifically, if, for a fixed population distribution, the house size and allocation can be scaled down within the set of integers, then the apportionment should be correspondingly scaled down. Balinski and Young (2001) include this property among the minimal requirements for a "reasonable" apportionment method. We argue that this property is better understood as a consistency requirement since quota-based apportionments that are "less proportional" meet this requirement while others that are "more proportional" do not. We also show that the family of quotatone methods based on stationary divisors (including the quota method) do not satisfy this property.

We study thermal production of dark matter (DM) in a realization of the minimal models of Ref.~\cite{Bonnefoy:2023afx}, where parity is used to solve the strong CP problem by transforming the entire Standard Model (SM) into a mirror copy. Although the mirror electron $e^{\prime}$ is a good DM candidate, its viability is mired by the presence of the mirror up-quark $u^{\prime}$, whose abundance is intimately related to the $e^{\prime}$ abundance and must be suppressed. This can be achieved through a sequential freeze-in mechanism, where mirror photons are first produced from SM gluons, and then the mirror photons produce $e'$. After computing the details of this double freeze-in, we discuss the allowed parameter space of the model, which lies at the threshold of experimental observations. We find that this origin of $e'$ DM requires a low reheating temperature after inflation and is consistent with the baryon asymmetry arising from leptogenesis, providing mirror neutrinos have a significant degeneracy. Finally, we show that this $e'$ DM is not compatible with Higgs Parity, the simplest scheme with exact parity, unless SM parameters deviate significantly from their central values or the minimal model is extended., Comment: 19 pages and 10 figures; typos corrected. V3: version published in PRD

We present radial velocity measurements of the very bright ($V\sim5.7$) nearby F star, DMPP-4 (HD 184960). The anomalously low Ca II H&K emission suggests mass loss from planets orbiting a low activity host star. Periodic radial velocity variability with $\sim 10$ ms$^{-1}$ amplitude is found to persist over a $>4$ year timescale. Although the non-simultaneous photometric variability in four TESS sectors supports the view of an inactive star, we identify periodic photometric signals and also find spectroscopic evidence for stellar activity. We used a posterior sampling algorithm that includes the number of Keplerian signals, $N_\textrm{p}$, as a free parameter to test and compare (1) purely Keplerian models (2) a Keplerian model with linear activity correlation and (3) Keplerian models with Gaussian processes. A preferred model, with one Keplerian and quasi-periodic Gaussian process indicates a planet with a period of $P_\textrm{b} = 3.4982^{+0.0015}_{-0.0027}$ d and corresponding minimum mass of $m_\textrm{b}\,\textrm{sin}\,i = 12.2^{+1.8}_{-1.9}$ M$_\oplus$. Without further high time resolution observations over a longer timescale, we cannot definitively rule out the purely Keplerian model with 2 candidates planets with $P_\textrm{b} = 2.4570^{+0.0026}_{-0.0462}$ d, minimum mass $m_\textrm{b}\,\textrm{sin}\,i = 8.0^{+1.1}_{-1.5}$ M$_\oplus$ and $P_\textrm{c} = 5.4196^{+0.6766}_{-0.0030}$ d and corresponding minimum mass of $m_\textrm{b}\,\textrm{sin}\,i = 12.2^{+1.4}_{-1.6}$ M$_\oplus$. The candidate planets lie in the region below the lower-envelope of the Neptune Desert. Continued mass loss may originate from the highly irradiated planets or from an as yet undetected body in the system., Comment: 19 pages, 11 figures. Accepted for publication in MNRAS

We present a novel mechanism for gravitational wave generation in the early Universe. Light spectator scalar fields during inflation can acquire a blue-tilted power spectrum due to stochastic effects. We show that this effect can lead to large curvature perturbations at small scales (induced by the spectator field fluctuations) while maintaining the observed, slightly red-tilted curvature perturbations at large cosmological scales (induced by the inflaton fluctuations). Along with other observational signatures, such as enhanced dark matter substructure, large curvature perturbations can induce a stochastic gravitational wave background (SGWB). The predicted strength of SGWB in our scenario, $\Omega_{\rm GW}h^2 \simeq 10^{-20} - 10^{-15}$, can be observed with future detectors, operating between $10^{-5}$ Hz and 10 Hz. We note that, in order to accommodate the newly reported NANOGrav observation, one could consider the same class of spectator models. At the same time, one would need to go beyond the simple benchmark considered here and consider a regime in which a misalignment contribution is also important., Comment: 12 pages, 5 figures

The methods of single transferable vote (STV) and sequential ranked-choice voting (RCV) are different methods for electing a set of winners in multiwinner elections. STV is a classical voting method that has been widely used internationally for many years. By contrast, sequential RCV has rarely been used, and only recently has seen an increase in usage as several cities in Utah have adopted the method to elect city council members. We use Monte Carlo simulations and a large database of real-world ranked-choice elections to investigate the behavior of sequential RCV by comparing it to STV. Our general finding is that sequential RCV often produces different winner sets than STV. Furthermore, sequential RCV is best understood as an excellence-based method which will not produce proportional results, often at the expense of minority interests.

In ranked-choice elections voters cast preference ballots which provide a voter's ranking of the candidates. The method of ranked-choice voting (RCV) chooses a winner by using voter preferences to simulate a series of runoff elections. Some jurisdictions which use RCV limit the number of candidates that voters can rank on the ballot, imposing what we term a truncation level, which is the number of candidates that voters are allowed to rank. Given fixed voter preferences, the winner of the election can change if we impose different truncation levels. We use a database of 1171 real-world ranked-choice elections to empirically analyze the potential effects of imposing different truncation levels in ranked-choice elections. Our general finding is that if the truncation level is at least three then restricting the number of candidates which can be ranked on the ballot rarely affects the election winner.

Ranked-choice voting anomalies such as monotonicity paradoxes have been extensively studied through creating hypothetical examples and generating elections under various models of voter behavior. However, very few real-world examples of such voting paradoxes have been found and analyzed. We investigate two single-transferable vote elections from Scotland that demonstrate upward monotonicity, downward monotonicity, no-show, and committee size paradoxes. These paradoxes are rarely observed in real-world elections, and this article is the first case study of such paradoxes in multiwinner elections.

Single Transferable Vote (STV) is a voting method used to elect multiple candidates in ranked-choice elections. One weakness of STV is that it fails multiple fairness criteria related to monotonicity and no show paradoxes. We analyze 1,079 local government STV elections in Scotland to estimate the frequency of such monotonicity anomalies in real-world elections, and compare our results with prior empirical and theoretical research about the rates at which such anomalies occur. In 62 of the 1079 elections we found some kind of monotonicity anomaly. We generally find that the rates of anomalies are similar to prior empirical research and much lower than what most theoretical research has found. The STV anomalies we find are the first of their kind to be documented in real-world multiwinner elections., Comment: 42 pages

The November 2022 ranked choice election for District 4 School Director in Oakland, CA, was very interesting from the perspective of social choice theory. The election did not contain a Condorcet winner and exhibited downward and upward monotonicity paradoxes, for example. Furthermore, an error in the settings of the ranked choice tabulation software led to the wrong candidate being declared the winner. This article explores the strange features of this election and places it in the broader context of ranked choice elections in the United States.

From the perspective of social choice theory, ranked-choice voting (RCV) is known to have many flaws. RCV can fail to elect a Condorcet winner and is susceptible to monotonicity paradoxes and the spoiler effect, for example. We use a database of 182 American ranked-choice elections for political office from the years 2004-2022 to investigate empirically how frequently RCV's deficiencies manifest in practice. Our general finding is that RCV's weaknesses are rarely observed in real-world elections, with the exception that ballot exhaustion frequently causes majoritarian failures.

The August 2022 Alaska Special Election for US House contained many interesting features from the perspective of social choice theory. This election used instant runoff voting (often referred to as ranked choice voting) to elect a winner, and many of the weaknesses of this voting method were on display in this election. For example, the Condorcet winner is different from the instant runoff winner, and the election demonstrated a monotonicity paradox. The election also demonstrated a no show paradox; as far as we are aware, this election represents the first document American ranked choice election to demonstrate this paradox.

In this article we explain why the November 2021 election for the Ward 2 city council seat in Minneapolis, MN, may be the mathematically most interesting ranked choice election in US history.

We lay out a comprehensive physics case for a future high-energy muon collider, exploring a range of collision energies (from 1 to 100 TeV) and luminosities. We highlight the advantages of such a collider over proposed alternatives. We show how one can leverage both the point-like nature of the muons themselves as well as the cloud of electroweak radiation that surrounds the beam to blur the dichotomy between energy and precision in the search for new physics. The physics case is buttressed by a range of studies with applications to electroweak symmetry breaking, dark matter, and the naturalness of the weak scale. Furthermore, we make sharp connections with complementary experiments that are probing new physics effects using electric dipole moments, flavor violation, and gravitational waves. An extensive appendix provides cross section predictions as a function of the center-of-mass energy for many canonical simplified models., Comment: 105 pages, 41 figures, 5 tables

Parity solutions to the strong CP problem are a compelling alternative to approaches based on Peccei-Quinn symmetry, particularly given the expected violation of global symmetries in a theory of quantum gravity. The most natural of these solutions break parity at a low scale, giving rise to a host of experimentally accessible signals. We assess the status of the simplest parity-based solution in light of LHC data and flavor constraints, highlighting the prospects for near-future tests at colliders, tabletop experiments, and gravitational wave observatories. The origin of parity breaking and associated gravitational effects play crucial roles, providing new avenues for discovery through EDMs and gravity waves. These experimental opportunities underline the promise of generalized parity, rather than Peccei-Quinn symmetry, as a robust and testable solution to the strong CP problem.

Despite research demonstrating the importance of language comprehension to later reading abilities, curriculum based measures to assess language comprehension abilities in preschoolers remain lacking. The Assessment of Story Comprehension (ASC) features brief, child-relevant stories and a series of literal and inferential questions with a focus on causal and predictive inference skills surrounding the main story grammar components and a novel vocabulary word. Following an overview of the iterative development process and pilot studies, this article presents preliminary evidence of the fidelity of administration, reliability of scoring, alternate form reliability, and validity of the ASC. In all, 237 preschoolers,ages 3 to 5 years old, participated in this study. Fidelity of administration and scoring reliability averaged over 90%.Concurrent validity with two established language measures revealed correlations ranging from 0.67 to 0.81. Test-retest reliability and internal consistency also indicated high levels of reliability for this new tool; however, alternate form reliability results suggest further work is needed. Preliminary results indicate that the ASC holds promise as a viable curriculum based measure that early childhood educators can use for monitoring preschoolers' progress in language comprehension. [This article was published in "Assessment for Effective Intervention" (EJ1151233).]

Purpose: We investigated a small-group intervention designed to teach vocabulary and comprehension skills to preschoolers who were at risk for language and reading disabilities. These language skills are important and reliable predictors of later academic achievement. Method: Preschoolers heard prerecorded stories 3 times per week over the course of a school year. A cluster randomized design was used to evaluate the effects of hearing storybooks with and without embedded vocabulary and comprehension lessons. A total of 32 classrooms were randomly assigned to experimental and comparison conditions. Approximately 6 children per classroom demonstrating low vocabulary knowledge, totaling 195 children, were enrolled. Results: Preschoolers in the comparison condition did not learn novel, challenging vocabulary words to which they were exposed in story contexts, whereas preschoolers receiving embedded lessons demonstrated significant learning gains, although vocabulary learning diminished over the course of the school year. Modest gains in comprehension skills did not differ between the two groups. Conclusion: The Story Friends curriculum appears to be highly feasible for delivery in early childhood educational settings and effective at teaching challenging vocabulary to high-risk preschoolers. [This article was published in "Journal of Speech, Language, and Hearing Research" (EJ1107550).]

The vertex-centric programming model is an established computational paradigm recently incorporated into distributed processing frameworks to address challenges in large-scale graph processing. Billion-node graphs that exceed the memory capacity of standard machines are not well-supported by popular Big Data tools like MapReduce, which are notoriously poor-performing for iterative graph algorithms such as PageRank. In response, a new type of framework challenges one to Think Like A Vertex (TLAV) and implements user-defined programs from the perspective of a vertex rather than a graph. Such an approach improves locality, demonstrates linear scalability, and provides a natural way to express and compute many iterative graph algorithms. These frameworks are simple to program and widely applicable, but, like an operating system, are composed of several intricate, interdependent components, of which a thorough understanding is necessary in order to elicit top performance at scale. To this end, the first comprehensive survey of TLAV frameworks is presented. In this survey, the vertex-centric approach to graph processing is overviewed, TLAV frameworks are deconstructed into four main components and respectively analyzed, and TLAV implementations are reviewed and categorized.

We consider the non-positivity of the Hilbert coefficients for a parameter ideal of a commutative Noetherian local ring. In particular, we show that the second Hilbert coefficient of a parameter ideal of depth at least d-1 is always non-positive and give a condition for the coefficient to be zero. With the added condition that the depth of the associated graded ring is also at least d- we show $e_{i}(q) \leq 0$ for $i=1, ..., d$.

Following the definitions of the algebras of differential operators, $\beta$-differential operators, and the quantum differential operators on a noncommutative (graded) algebra given in \cite{LR}, we describe these operators on the free associative algebra. We further study their properties., Comment: 25 pages

We introduce a new class of semigroups arising from a restricted class of asynchronous automata. We call these semigroups "expanding automaton semigroups." We show that the class of synchronous automaton semigroups is strictly contained in the class of expanding automaton semigroups, and that the class of expanding automaton semigroups is strictly contained in the class of asynchronous automaton semigroups. We investigate the dynamics of expanding automaton semigroups acting on regular rooted trees, and show that undecidability arises in these actions. We show that this class is not closed under taking normal ideal extensions, but the class of asynchronous automaton semigroups is closed under taking these extensions. We construct every free partially commutative monoid as a synchronous automaton semigroup., Comment: 31 pages, 4 figures

Withdrawn on account of a crucial error in the main theorem, Comment: Withdrawn

ACL2 was used to prove properties of two simplification procedures. The procedures differ in complexity but solve the same programming problem that arises in the context of a resolution/paramodulation theorem proving system. Term rewriting is at the core of the two procedures, but details of the rewriting procedure itself are irrelevant. The ACL2 encapsulate construct was used to assert the existence of the rewriting function and to state some of its properties. Termination, irreducibility, and soundness properties were established for each procedure. The availability of the encapsulation mechanism in ACL2 is considered essential to rapid and efficient verification of this kind of algorithm., Comment: 6 pages

We report on an effort to develop methodologies for formal verification of parts of the Multi-Purpose Daemon (MPD) parallel process management system. MPD is a distributed collection of communicating processes. While the individual components of the collection execute simple algorithms, their interaction leads to unexpected errors that are difficult to uncover by conventional means. Two verification approaches are discussed here: the standard model checking approach using the software model checker SPIN and the nonstandard use of a general-purpose first-order resolution-style theorem prover OTTER to conduct the traditional state space exploration. We compare modeling methodology and analyze performance and scalability of the two methods with respect to verification of MPD., Comment: 12 pages, 3 figures, 1 table

Mace4 is a program that searches for finite models of first-order formulas. For a given domain size, all instances of the formulas over the domain are constructed. The result is a set of ground clauses with equality. Then, a decision procedure based on ground equational rewriting is applied. If satisfiability is detected, one or more models are printed. Mace4 is a useful complement to first-order theorem provers, with the prover searching for proofs and Mace4 looking for countermodels, and it is useful for work on finite algebras. Mace4 performs better on equational problems than did our previous model-searching program Mace2., Comment: 17 pages

OTTER is a resolution-style theorem-proving program for first-order logic with equality. OTTER includes the inference rules binary resolution, hyperresolution, UR-resolution, and binary paramodulation. Some of its other abilities and features are conversion from first-order formulas to clauses, forward and back subsumption, factoring, weighting, answer literals, term ordering, forward and back demodulation, evaluable functions and predicates, Knuth-Bendix completion, and the hints strategy. OTTER is coded in ANSI C, is free, and is portable to many different kinds of computer., Comment: 66 pages

In this note we show that the equational theory of all lattices is defined by a single absorption law. The identity of length 29 with 8 variables is shorter than previously known such equations defining lattices., Comment: 5 pages

The National Fusion Collaboratory (NFC) project was created to advance scientific understanding and innovation in magnetic fusion research by enabling more efficient use of existing experimental facilities through more effective integration of experiment, theory, and modeling. To achieve this objective, NFC introduced the concept of "network services", which build on top of computational Grids, and provide Fusion codes, together with their maintenance and hardware resources as a service to the community. This mode of operation requires the development of new authorization and enforcement capabilities. In addition, the nature of Fusion experiments places strident quality of service requirements on codes run during the experimental cycle. In this paper, we describe Grid computing requirements of the Fusion community, and present our first experiments in meeting those requirements.

We describe our experiences in using SPIN to verify parts of the Multi Purpose Daemon (MPD) parallel process management system. MPD is a distributed collection of processes connected by Unix network sockets. MPD is dynamic: processes and connections among them are created and destroyed as MPD is initialized, runs user processes, recovers from faults, and terminates. This dynamic nature is easily expressible in the SPIN/PROMELA framework but poses performance and scalability challenges. We present here the results of expressing some of the parallel algorithms of MPD and executing both simulation and verification runs with SPIN., Comment: 19 pages; 8 figures; 3 tables

The reasons for using low-lying Dirac eigenmodes to probe the local structure of topological charge fluctuations in QCD are discussed, and it is pointed out that the qualitative double-peaked behavior of the local chiral orientation probability distribution in these modes is necessary, but not sufficient for dominance of instanton-like fluctuations. The results with overlap Dirac operator in Wilson gauge backgrounds at lattice spacings ranging from a~0.04 fm to a~0.12 fm are reported, and it is found that the size and density of local structures responsible for double-peaking of the distribution are in disagreement with the assumptions of the Instanton Liquid Model. More generally, our results suggest that vacuum fluctuations of topological charge are not effectively dominated by locally quantized (integer-valued) lumps in QCD., Comment: 29 pages, 13 figures; v2: minor improvements in presentation, results and conclusions unchanged, version to appear in PRD

We discuss the utility of low-lying Dirac eigenmodes for studying the nature of topological charge fluctuations in QCD. The implications of previous results using the local chirality histogram method are discussed, and the new results using the overlap Dirac operator in Wilson gauge backgrounds at lattice spacings ranging from a~0.04 fm to a~0.12 fm are reported. While the degree of local chirality does not change appreciably closer to the continuum limit, we find that the size and density of local structures responsible for chiral peaking do change significantly. The resulting values are in disagreement with the assumptions of the Instanton Liquid Model. We conclude that the fluctuations of topological charge in the QCD vacuum are not locally quantized., Comment: 3 pages, 4 figures, Lattice2001(confinement)

MACE is a program that searches for finite models of first-order statements. The statement to be modeled is first translated to clauses, then to relational clauses; finally for the given domain size, the ground instances are constructed. A Davis-Putnam-Loveland-Logeman procedure decides the propositional problem, and any models found are translated to first-order models. MACE is a useful complement to the theorem prover Otter, with Otter searching for proofs and MACE looking for countermodels., Comment: 10 pages

The low-lying eigenmodes of the Dirac operator associated with typical gauge field configurations in QCD encode, among other low-energy properties, the physics behind the solution to the $U_A(1)$ problem (i.e. the origin of the $\eta'$ mass), the nature of spontaneous chiral symmetry breaking, and the physics of string-breaking, quark-antiquark pair production, and the OZI rule. Moreover, the space-time chiral structure of these eigenmodes reflects the space-time topological structure of the underlying gauge field. We present evidence from lattice QCD on the local chiral structure of low Dirac eigenmodes leading to the conclusion that topological charge fluctuations of the QCD vacuum are not instanton-dominated. The result supports Witten's arguments that topological charge is produced by confinement-related gauge fluctuations rather than instantons., Comment: 35 pages, 11 figures

Following the definition of quantum differential operators given by Lunts and Rosenberg in (Sel. math., New ser. 3 (1997) 335--359), we show that the ring of quantum differential operators on the affine line is the ring generated by x and \del, the familiar differential operators on the line, along with two additional operators which we call \del^\beta^1 and \del^\beta^-1. We describe this ring both as a subring of the ring of graded endomorphisms and as a ring given by generators and relations. From this starting point, we are able to describe the ring of quantum differential operators on affine n-space and to construct the ring of global quantum differential operators on the projective line., Comment: 26 pages, references added. To appear in International Journal of Mathematics

The universal enveloping algebra U(g) of a Lie algebra g acts on its representation ring R through D(R), the ring of differential operators on R. A quantised universal enveloping algebra (or "quantum group") is a deformation of a universal enveloping algebra and acts not through the differential operators of its representation ring but through the quantised differential operators of its representation ring. We present this situation for the quantum group of sl_2., Comment: 18 pages, references added, address changed

The Radioisotope Power System (RPS) Program was established in 2009 to manage RPS investments for NASA to ensure the availability of RPS for the exploration of the solar system in environments where conventional solar or chemical power generation is impractical or impossible. The RPS Program is a multi-center and multi-agency program. NASA is in partnership with the Department of Energy (DOE) Office of Nuclear Energy to provide technologically robust nuclear power system solutions to robotic spacecraft and exploration missions. During the last decade, the RPS Program and DOE have supported missions, developed technologies and initiated new power system developments. These technical areas, as all technical areas, have challenges and standard engineering solutions; however, clearing the path to enable the technical work requires agreements to be established. This paper describes a process by which two governmental agencies have established a successful basis to accomplish the needed work.

This study analysed the expectations and experiences of students on a five-year undergraduate ("n"?=?91) and four-year graduate entry ("n"?=?47) veterinary medicine degree programme relating to academic feedback. Qualitative and quantitative methodologies were used to explore new students' expectations and prior experiences of feedback and capture experiences across one academic year. The majority of the students expect no less feedback at university than at school. Students' experiences of the course highlighted themes of not knowing what was expected of them, a perceived need for more guidance and the importance of timely feedback. The impact of the staff-student relationship on how students obtain and perceive feedback and the emotional impact of positive and negative feedback were also highlighted. In addition, a recurring theme was the social context of veterinary medicine with issues relating to high academic achievers, competition between students and the need to gain professional and clinical skills. This study confirms a mismatch in student expectations versus experience. The paper draws on a rich data-set based on both quantitative and qualitative methods and is the first study of this type to be carried out in the context of students of veterinary medicine. (Contains 3 tables and 1 figure.)

"Authenticity in teaching" has been recognized as an important yet under-researched phenomenon. To gain greater insight into the meaning of authenticity in teaching in adult and higher education settings, the authors delved into some of the philosophical and educational literature on authenticity, giving particular attention, but not confining their review, to the work of Taylor, Heidegger, and Noddings. This study is one of "making sense of authenticity in teaching" in light of the conceptions of authenticity underlying the reviewed texts. Authenticity in teaching emerged as a multidimensional phenomenon, and the findings are presented in the form of multiple features associated with it. Inspired by Taylor's concept of horizons of significance and Palmer's notion of the subject-centered classroom, the authors further propose that one dimension of authenticity in teaching relates to educators' care for the subject matter and thus engaging students in genuine dialogue around ideas that matter.