Will It be a Tough Year?

While there may be some glimmers of hope about a turnaround to the U.S. economy, such as decreasing unemployment, Virginia CPAs aren\u27t betting on a huge recovery in the next year. The second annual VSCPA Economic Outlook Survey reveals Virginia CPAs are more pessimistic about the United States and Virginia economies than they were last year, but they are actually more optimistic about Virginia\u27s economy compared to the United States as a whole. Likewise, VSCPA members continue to feel good about the economic outlook in Virginia relative to neighboring states

A Fair Shake: How close can the sum of nn-sided dice be to a uniform distribution?

Two possibly unfair $n$-sided dice, both labelled $1, 2, \ldots, n$, are rolled, and the sum is recorded. How should the dice's sides be weighted so that the resulting sum is closest to the uniform distribution on $2, 3, \ldots, 2n$? We answer this question by explicitly identifying the optimal pair of dice. This resolves a question raised by Gasarch and Kruskal in 1999 in a surprising way. We present additional results for the case of more than two possibly unfair $n$-sided dice and for the hypothetical case where the weights on each die are permitted to be negative, but must still sum to one.Comment: 12 page

Instructional Case: Can Management Accounting Help Aid Associations Make Tough Choices in Haiti?

Based on an actual situation, this case explores the use of management accounting analysis in a difficult make-or-buy decision in the real world of humanitarian aid. An aid organization produces a specially designed, highly nutritious peanut butter medicine to save the lives of Haiti’s malnourished children. The challenge is deciding whether to source the peanuts from Haitian farmers and pay more or from foreign suppliers and pay less. Students perform both quantitative and qualitative cost-benefit, break-even, operating leverage, and product costing analysis. Performance measurement, incentive issues, short-term versus long-term thinking, micro and macroeconomics, and ethical issues are also considered. The case is best suited for cost accounting and managerial (particularly MBA managerial) accounting courses

The Effects of Being in a “New Relationship” on Levels of Testosterone in Men.

In light of previous research showing that different types of relationships affect levels of testosterone in men, this study examined whether categorizing relationship types according to relationship length can shed further light on variations in levels of testosterone. Salivary testosterone samples were obtained from a sample of men and details about their relationship status, sociosexual orientation, extra-pair sexual interest, and their perceptions of their relationships were recorded. Using a median split analysis, participants who indicated that they had been in their relationship for less than 12 months were categorized as being in “new relationships” and those in longer relationships being categorized as in long-term relationships. Results showed that levels of testosterone of single men and men in new relationships did not differ, but both had significantly greater levels of testosterone than men in long-term relationships. Differences in levels of testosterone were unrelated to sociosexual orientation and extra-pair sexual interest. These findings support the evolutionary explanation of levels of testosterone in men varying in accordance with their internal motivation to seek new potential mates

Computational Rationalizations of Mechanism and Stereocontrol in Small-Molecule Lewis Base Organocatalysis

My work has focused on investigating synthetic organic reactions using applied computational methods. Non-covalent interactions are critical to catalysis, mechanism, and stereoselectivity, with the most prominent interaction for isothioureas being the S···O contact between the catalyst sulfur atom and the oxygen of the acyl group. A comprehensive joint experimental and computational investigation into the isothiourea-catalyzed transformation of allylic ammonium ester salt substrates into α- amino acid derivatives. Kinetic isotope effects (KIEs) and description of the potential energy surface allowed accurate corroboration of computed secondary KIEs with experiment. The turnover-limiting and stereodeterming transition state is a [2,3]- sigmatropic rearrangement of an allylic ammonium ylide. Stereoselectivity is afforded through rigidification of the catalyst-substrate complex through a S···O non-covalent interaction. In such an arrangement, rearrangement takes place endo, anti to the catalyst stereodirecting group, allowing a stabilizing π-cation between the substrate and planar positively-charged catalyst to select for the major TS. Isothiourea-catalyzed annulations of benzoxazoles and benzothiazoles were discovered to proceed to lactone or lactam products on the basis of the benzothiazole’s ability to engage in a second S···O interaction in addition the substrate-catalyst S···O interaction already present in both lactonization and lactamization TSs. In the absence of the second S···O, a C–H···O between the substrate and the catalyst oxygen atom favors lactonization. Computed TSs and truncated model systems discovered and detailed the interplay between the two non-bonding interactions (S···O and C–H···O), which ultimately leads to chemodivergence when using thiazole or oxazole derived substrates. Interactions between S and O atoms have previously been elements of enantiocontrol, but have never been evoked as central to chemoselectivity. A study on the scope and origins of stereocontrol in the kinetic resolution of tertiary oxindole alcohols illustrates the importance of the substrate amide C=O moiety interacting with the isothiourea catalyst (C=O···isothiouronium) as imparting high selectivity. Partial charge calculations of the acylated catalyst point to a positive charge on the central isothiourea carbon (isothiouronium) Computed TSs allowed the development of a stereocontrol model in which stabilization of the isothiouronium with the substrate amide C=O leads to faster acylation of the (S)-alcohol. Hammett parameters and amide C=O stretching frequencies of the substrate showed good correlation with the s factor, in agreement with theoretical predictions. Regiodivergent and catalyst-selective O- to C- or N-carboxyl transfer is disclosed, with DMAP catalysis favoring N-carboxylation and NHC catalysis leading to selective Ccarboxylation. Computations unveiled the mechanism and source of regiodivergence from the mechanistically shared enolate intermediate. Computed TSs for the N- and Ccarboxylation pathways for both DMAP and NHC catalysts showed that greater spatial overlap in the ion pair consisting of the overall negatively-charged enolate species and the positively-charged acylated catalyst leads to regiodivergence for each catalyst. A theoretical and experimental project studying the formation mechanism and reactivity of highly unstable aza-ortho-quinone methide (aoQM) intermediates in synthesis and asymmetric N-heterocyclic carbene (NHC) catalysis. Compared to their oxygen analogs (ortho-quinone methides), aoQMs were found to be >10 kcal/mol more unstable. A byproduct of aoQM formation in the presence of cesium carbonate base is cesium chloride, with a computed equilibrium in favor of cesium chloride of ~30 kcal/mol. A nucleophilic substitution pathway which bypasses aoQM formation was considered, but was found as consistently higher in energy than the aoQM pathway once the cesium carbonate equilibrium is considered. With the aoQM-mediated mechanism established, a stereocontrol model was developed for the NHC-catalyzed asymmetric synthesis of dihydroquinolones

History is fiction, fiction history : questions of history formation in Melville's Moby-Dick

Golo Mann, who is recognized in a recent article as one of the first historians to realize that their work “does not reproduce ‘what actually happened’ so much as represent it from a particular point of view (Burke, “History of Events” 290), describes the ideal historian as someone who must “swim with the stream of events” and tell the story as if he was there when the events occurred while analyzing them as an outside “better informed observer.” In combining these two methods, the historian must be sure to “yield a sense of homogeneity […] without the narrative falling apart” (Mann 7). While most contemporary criticism surrounding Herman Melville’s Moby-Dick focuses on various metaphorical readings, if we return to a more literal reading we see that Ishmael is Mann’s ideal historian. Not only is Ishmael carried along with the events “as though he was present” (7), he actually was present, and he does return to the events a later, better informed observer. With this in mind, an often decried literal reading of Moby-Dick adds to the current metaphorical scholarship because it sees Ishmael as a common man in a rapidly chancing society and explores how that man comes to terms with his own existence in such an impersonal world. However, because Ishmael is unsure of how to deal with the events of his past and how to capture the meaning of those events on paper, he has problems with what Mann calls the “homogeneity” of his history and cannot keep his narrative from falling apart. Through an analysis of the similarities and differences of the assumptions underlying both the creation of history and the creation of fiction, and a subsequent look at how those conventions are both obeyed and subverted in Moby-Dick, we can enhance an understanding of Melville’s novel as the narrator’s attempt to come to terms with his own traumatic past

Large molecular systems landscape uncovers T cell trapping in human skin cancer

Immune surveillance of tumour cells is an important function of CD8 T lymphocytes, which has failed in cancer for reasons still unknown in many respect but mainly related to cellular processes in the tumour microenvironment. Applying imaging cycler microscopy to analyse the immune contexture in a human skin cancer we could identify and map 7,000 distinct cell surface-associated multi-protein assemblies. The resulting combinatorial geometry-based high-functional resolution led to discovery of a mechanism of T cell trapping in the epidermis, which involves SPIKE, a network of suprabasal keratinocyte projections piercing and interconnecting CD8 T cells. It appears initiated by clusters of infrabasal T and dendritic cells connected via cell projections across a fractured basal lamina to suprabasal keratinocytes and T lymphocytes

Opportunities and challenges in triboelectric nanogenerator (TENG) based sustainable energy generation technologies: a mini-review

Almost ten years after the publication of the first triboelectric nanogenerator (TENG) paper in 2012, this review gives a brief overview of recent technological advances in applying TENG technology to key sustainable and renewable energy applications. The paper examines progress of TENG applications in four key areas such as wearables, wave, wind and transport. TENGs have advanced hugely since its inception and approaches to apply them to a host of freely available sources of kinetic energy have been developed. However, electrical output remains low (mostly less than 500 W/m2) compared to some other forms of energy generation and the main challenges for the future appear to be further boosting output power and current, fabricating advanced TENGs economically and designing TENGs for lifetime survival in various practical environments. It concludes with a discussion of pressing challenges for realizing the full potential of TENGs in these application areas particularly from the perspective of materials and fabrication. It is noted that considerable research and development should be required to enable large-scale manufacture of TENG based devices. TENGs will be instrumental in the future evolution of the Internet of Things (IoTs), human-machine interfacing, machine learning applications and ‘net-zero emission’ technologies