Original Choice Research Articles

Transcription-Coupled Structural Dynamics of Topologically Associating Domains Regulate Replication Origin Efficiency

Metazoan cells only utilize a small subset of the potential DNA replication origins to duplicate the whole genome in each cell cycle. Origin choice is linked to cell growth, differentiation, and replication stress. Despite various genetic and epigenetic signatures have been suggested to define active origins, it remains elusive how the selection of origins is determined. The classic Rosette model proposes that the origins clustered at the center of a chromatin domain are preferentially and simultaneously fired, but direct imaging evidence has been lacking due to insufficient spatial resolution. Here, we applied dual-color stochastic optical reconstruction microscopy (STORM) super-resolution imaging to map the spatial distribution of origins within individual topologically associating domains (TADs). We found that replication generally initiates at the spatial boundary of a TAD at the G1/S transition, in contrary to the Rosette model. Intriguingly, while both active and dormant origins are distributed homogeneously in the TAD during the G1 phase, active origins relocate to the TAD periphery at the G1/S transition. We proved that such origin relocalization is dependent on both transcription and CTCF-mediated chromatin structure. Further, we observed that the replication machinery protein PCNA forms immobile clusters around the TADs at the G1/S transition, which explains why origins at the TAD periphery are preferentially fired. Thus, we propose a “Chromatin Re-organization Induced Selective Initiation” (CRISI) model that the transcription-coupled chromatin structural re-organization determines the selection of replication origins, which transcends the scope of specific genetic and epigenetic signatures for origin efficiency. Our in situ super-resolution imaging unveiled coordination among DNA replication, transcription, and chromatin organization inside individual TADs, providing new insights into the biological functions of sub-domain chromatin structural dynamics.

Reference systems and their origins

It is demonstrated how the choice of a reference system origin influences our interpretation of the natural laws. Instead of placing it arbitrarily as is customary in mechanics, we locate it at an energy minimum, or zero point of material systems. In an example from celestial mechanics, the sun defines the point of minimum gravitational potential and preferred origin for the planetary system. As a comparison, Heisenberg's derivation of quantum kinematics is shown to be deficient, because microscopes do not define the point of minimum energy of an atomic system. To improve upon it, new interpretations of quantum kinematics and mechanics are proposed by locating the reference system origin at the zero point of an atomic system, where the Hamiltonian, H = T + V, equals zero. Experiments with atomic clocks are cited in support of the new physical model. The Schwarzschild solution relative to a mass point is proposed as the preferred interpretation of a general relativity theory due to the location of the origin at a zero point. These interpretations of long-standing theories provide new points of view to familiar problems.

Abstract P4-14-07: Treatment patterns for metastatic hormone receptor-positive breast cancer: Comparing expert and community practice

Abstract Background Endocrine therapies and CDK4/6 inhibitors have dramatically improved outcomes for patients with hormone receptor-positive (HR+) metastatic breast cancer (MBC). To help inform treatment decisions among healthcare providers (HCPs) caring for patients with MBC, we have developed and regularly updated an online treatment decision support tool that provides recommendations from multiple breast cancer experts for specifically defined patient scenarios. Here we report data for HR+/HER2- MBC cases entered into the tool since 2016, capturing self-reported practice trends from HCPs compared with matched treatment recommendations from experts. Methods For the most recent MBC treatment tool (published October 2018), 5 breast cancer experts provided treatment consultation for 549 unique MBC case scenarios based on a simplified set of variables: disease phenotype, previous systemic therapy, visceral crisis (yes/no), rate of disease progression, and the presence or absence of germline BRCA1/2 mutations. HCPs used selection menus to enter patient and disease factors based on these variables along with their intended treatment plan. When completed, the experts’ treatment recommendations for that specific patient case were shown to the HCPs at which time they were asked to indicate if the expert recommendations changed their planned treatment. Results From October 2018 through June 2019, 603 HCPs entered 1127 patient case scenarios, including 581 HR+/HER2- MBC cases, in the most recent online tool. A comparison of expert and HCP treatment choices for select HR+/HER2- MBC case scenarios from the October 2016 and October 2018 tool is shown in the Table. In the setting of HR+/HER2- MBC, among those HCPs whose planned treatment differed from the consensus expert recommendation, 55% indicated that they would change their original choice of treatment. Conclusions CDK4/6 inhibitors have had a large impact on expert treatment recommendations for patients with HR+/HER2- MBC. However, data from this online treatment decision support tool suggest ongoing differences in practice between experts and community HCPs in this setting. For many cases entered into the tool, the practice of the majority of HCPs differed from expert consensus (Table). Consensus expert recommendations in this online tool changed the intended treatment plan of many using it and, therefore, can help optimize the care of patients with MBC. A detailed analysis of overall community practice trends for HR+/HER2- MBC along with a comparison of expert and HCP practice for different case scenarios will be presented. HR+/HER2- MBC Case Scenarios (no visceral crisis)Expert Consensus Recommendation (%)Expert Consensus Recommendation (%)HCP Practice Matched Expert Consensus Recommendation, % (n)HCP Practice Matched Expert Consensus Recommendation, % (n)2016201820162018de novoCDK4/6i + AI (100)CDK4/6i + AI (100)23 (111)32 (188)Previous (neo)adjuvant AICDK4/6i + FULV (92)CDK4/6i + FULV (90)22 (54)17 (77)Previous CDK4/6i + AIFULV (82)FULV ± EVE (92)0 (14)18 (40)Previous AI and CDK4/6i + FulvEVE + EXE (87)EVE + EXE (73)63 (19)28 (18) Citation Format: Timothy Quill, Sara Hurvitz, Kathy D. Miller, Ruth O'Regan, Tiffany A. Traina, Rachael Andrie, Kevin L. Obholz, Mohammad Jahanzeb. Treatment patterns for metastatic hormone receptor-positive breast cancer: Comparing expert and community practice [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-14-07.

Simple supergravity model of inflation constrained with Planck 2018 data

We study a model of inflation based on $\mathcal{N}=1$ supergravity essentially depending on one effective parameter. Under a field transformation we show that this model turns out to be equivalent to a previously studied supergravity model known to be ruled out with the original choice of the parameter. Such parameter measures the slope of the potential at observable scales. Through a Bayesian parameter estimation, it is shown how this model is compatible with recent CMB temperature measurements by {\it Planck 2018} giving rise to a simple, viable, single field model of inflation. The tensor to scalar ratio constraint is found to be $r_{0.002}<0.065$ with negative running. We discuss how observables are invariant under the field transformation which leaves unaltered the slow-roll parameters. As a consequence the use of one presentation of the model or its field-transformed version is purely a matter of convenience.

No Property in Man: Slavery and Antislavery at the Nation's Founding by Sean Wilentz

Reviewed by: No Property in Man: Slavery and Antislavery at the Nation's Founding by Sean Wilentz Aaron R. Hall (bio) Keywords Slavery, Antislavery, U.S. Constitution, Constitutional Convention, Abolition, Secession No Property in Man: Slavery and Antislavery at the Nation's Founding. By Sean Wilentz. (Cambridge, MA: Harvard University Press, 2018. Pp. 350. Cloth, $26.95.) The text of the U.S. Constitution did not spell out the word "slave" prior to the Reconstruction Amendments. Nor did its first framers adopt a human-chattel clause guaranteeing a national right to own people. As James Madison self-reported in his posthumously published "Notes of Debates in the Federal Convention of 1787," it would be "wrong to admit in the Constitution the idea that there could be property in men."1 This well-known constitutional absence (and quotation) has hardly troubled a scholarly consensus on the proslavery force of the framers' handiwork. The numerical incorporation of enslaved people in slave-state federal representation, provision for rendition of interstate fugitives from slavery, protection of the transatlantic slave trade, and promise of military might against insurrections showed that the Convention could ably weave slavery into the national fabric without saying its name. As soft antislavery sentiments yielded to hard bargaining behind closed doors, the Constitution embedded southern states in a robust federal polity and empowered their slaveholding leaders to govern. Sean Wilentz sees a more inspiring Founding in the words that framers declined to use. No Property in Man, a short and sweeping account of slavery's constitutional place from the Revolution through Emancipation, [End Page 388] presents Wilentz's vision of the original meaning and subsequent power of the textual absence of "slave." The Princeton historian insists that a majority in the Convention hewed assiduously to his book's titular principle, making good on Madison's remark, even as they framed architecture strengthening the enslavement of those designated as "other persons."2 As Wilentz puts it: "While they had no choice in the moment but to tolerate and even protect slavery where it existed, they would prepare for a nation in which there was no slavery, which would mean refusing to validate slavery's legitimacy in the Constitution" (59). This conscious refusal, undertaken not to obscure slavery but to deny it any constitutional sanction, laid the cornerstone of abolition. Wilentz's framers "left room" (2) for antislavery politics and "bequeathed grounds upon which slavery's expansion would later be challenged, with the ultimate objective of destroying American slavery completely" (22). All this rendered the Constitution a "paradox," not a compact with hell (22). And it explains why Wilentz laments that "historians still cling to [abolitionist William Lloyd] Garrison's denunciation" of the instrument as such (12). Because the Constitution's original meaning—something he largely treats as defined by authorial understanding—withheld recognition of slavery, later generations of antislavery constitutionalists stood on the right side of historical truth while proslavery interpretations defied the framers' will. Before the Civil War, Wilentz contends, Abraham Lincoln "closely studied Madison's notes" (254) and "sensed how the framers … offered his generation the instruments to cut out what he called the 'cancer' of slavery" (242). Secession followed his election because slaveholders could not endure a government that vindicated the Constitution's antislavery silence. At its heart, then, No Property in Man seeks to exorcise from contemporary historians the ghost of Garrison—as well as those of proslavery figures John Calhoun and Roger Taney, whose constitutional understandings Wilentz asserts rested on the same false notion of the Founding. This is a book thick with arguments. It tells of Revolutionary-era discourse against slavery, debates in the Convention, heated analysis advanced during ratification, and claims levied amid decades of political conflict over slavery; and it is replete with Wilentz's strong interpretive voice across these moments. No Property in Man convincingly foregrounds the importance of constitutional positions in configuring formal [End Page 389] politics that culminated in secession. It shows how passing time and new sectional issues collided with original choices. Its tight focus on arguments about the constitutional recognition of enslaved people as property yields a particularly lucid approach for linking together issues and fights over half a...

Optimal Group Size in Microlending

Microlending, where a bank lends to a small group of people without credit histories, began with the Grameen Bank in Bangladesh, and is widely seen as the creation of Muhammad Yunus, who received the Nobel Peace Prize in recognition of his largely successful efforts. Since that time the modeling of microlending has received a fair amount of academic attention. One of the issues not yet addressed in full detail, however, is the issue of the size of the group. Some attention has nevertheless been paid using an experimental and game theory approach. We, instead, take a mathematical approach to the issue of an optimal group size, where the goal is to minimize the probability of default of the group. To do this, one has to create a model with interacting forces, and to make precise the hypotheses of the model. We show that the original choice of Muhammad Yunus, of a group size of five people, is, under the right, and, we believe, reasonable hypotheses, either close to optimal, or even at times exactly optimal, i.e., the optimal group size is indeed five people.

Od tłumacza do poety i z powrotem. Twórczość przekładowa Adama Ważyka jako część literatury polskiej

From Translator to Poet and Back: Adam Ważyk’s Translation Output as Part of Polish Literature The article offers an analysis of Adam Ważyk’s translation work, particularly in the context of its influence on the shaping of contemporary Polish poetry. The author aims to showcase the impact of Ważyk’s translations on some of the recent developments within Polish literature; to this end, she employs the distinction between translatoras-envoy and translator-as-lawmaker, as proposed by Jerzy Jarniewicz. Ważyk is here seen as an example of a “lawmaker”, and compared to Piotr Sommer – another author influential within a similar audience. The author argues that in his original choice of what to translate, Ważyk was driven by a desire to project onto the Polish context – to reproduce in his native language – a set of poetic and social circumstances associated with the French avant-garde movement; finally it served the goal of making Ważyk’s own work more comprehensible to his Polish readers. At the turn of the 21st century a group of Polish poets who had expressed interest in Ważyk were also attracted to the work of poets translated by Ważyk; the influence of these foreign authors was thus mediated by Ważyk’s own work.

Do not Dispose of Historic Fluid Collections: Evaluating Research Potential and Range of Use

Abstract The use of specific preservative solutions by museum professionals to maintain fluid-preserved specimens has fluctuated over the years with advances in chemistry. The determining factors for the original choice of solution closely correlate with the historical parameters and original usage of the collections. Consequently, for any given collection, changes and substitutions over time in the types of preservative fluids used have likely occurred. The present comparative analysis of the state of brain preservation, carried out at macroscopic, microscopic, and molecular levels, allowed us to evaluate the effect of the different treatments applied over time to fluid-preserved collections. Our results confirm that the duration of formaldehyde exposure of the tissues clearly has an effect on their long-term preservation. Despite the controversies associated with the quality or use of some historic fixatives, modern analytical methods such as medical imagery reveal the preservation quality in historic specimens and their potential for future research use. However, the choice of fixatives and storage fluids to preserve the specimens is of critical importance because today's choices will influence the use of the specimen for advanced analytical methods in the future.

Out of equilibrium higher-order topological insulator: Floquet engineering and quench dynamics

Higher-order topological~(HOT) states,~hosting topologically protected modes on lower-dimensional boundaries,~such as hinges and corners, have recently extended the realm of the static topological phases.~Here we demonstrate the possibility of realizing a two-dimensional \emph{Floquet} second-order topological insulator, featuring corner-localized zero quasienergy modes and characterized by quantized Floquet qudrupolar moment $Q^{\rm Flq}_{xy}=0.5$, by periodically kicking a quantum spin Hall insulator (QSHI) with a discrete fourfold ($C_4$) and time-reversal (${\mathcal T}$) symmetry breaking Dirac mass perturbation.~Furthermore, we show that $Q^{\rm Flq}_{xy}$ becomes independent of the choice of origin as the system approaches the thermodynamic limit.~We also analyze the dynamics of a corner mode after a sudden quench, when the $C_4$ and ${\mathcal T}$ symmetry breaking perturbation is switched off, and find that the corresponding survival probability displays periodic appearances of complete, partial and no revival for long time, encoding the signature of corner modes in a QSHI.~Our protocol is sufficiently general to explore the territory of dynamical HOT phases in insulators and gapless systems.

Emotions, time, and strategy: The effects of happiness and sadness on strategic decision-making under time constraints

Managers often have limited available time to make high-quality strategic decisions that are both original and feasible. This joint objective is important but difficult to achieve because under time constraints, managers must combine different cognitive processes that are often influenced by emotional states. However, research investigating how time constraints and emotions interact and impact the quality of strategic decisions is scarce. Building upon the affect infusion model and information processing perspective, our experimental study involving 174 managers shows that the impact of time constraints and emotions varies across the two decision-making tasks of strategic idea generation and strategic choice. In particular, compared to the managers in a neutral emotional state under low time constraints, the happy managers under high time constraints seemed to generate fewer original and fewer feasible strategic ideas and appeared to make worse original strategic choices, while compared to the managers in a neutral emotional state under low time constraints, the sad managers under high time constraints made better original strategic choices. Our study contributes novel insight into behavioral strategy research by showing how time constraints and emotions causally and jointly influence different quality dimensions in various tasks involving strategic decision-making.

Trading on Food Quality due to Changes in Prices: Are There Any Nutritional Effects?

The analysis of changes in prices is not only important because they directly affect households’ affordability and, therefore, their food security but also because they may trigger changes in the composition of their food and drink choices. Thus, an increase in prices may force a household with limited resources to choose a bundle of goods with lower prices that substitute their original choices and are probably of lower quality. This paper considers the situation of each UK country and the implications that trading down in quality within a food and drink category has on nutrition. Two motivations to pursue these analyses are to explore the sort of substitutions that households do within a category due to an increase in prices and, in the UK leaving the European Union (Brexit) context, the impact that an increase in food prices may have on nutrition. After computing estimates for trading down for each country for the period 2007–2014, we regress the annual rate of change by nutrient with respect to the annual trading in quality for six food qualities that are major contributors of fat, sugar and salt to the diet. The results indicate that trading down in quality occurs in most of the studied categories and countries, and when households trade down, they move to products with worse nutritional quality. This points out the need to keep improving the quality of products through reformulation, ensure that consumers are well informed of nutritional quality of products and monitor the effect of changes in prices.

“Boss ceiling effect”: brand downgrading consumption of workplace employees

PurposePrevious literature suggests that people might purchase symbolic products to signal their social identity. However, in the organizational context, subordinates as customers might choose products with less brand prestige than what they want and can afford, just to make sure their choices are below the invisible “red-line” set by the brands of their supervisors. The authors term the phenomenon as “boss ceiling effect,” and term the behavior that people often downgrade their original choice to make sure the brand prestige is lower than that of the product owned by their boss as “downgrading behavior,” which have not been explored and well explained by existing literature so far. The paper aims to discuss this issue.Design/methodology/approachThe authors conduct qualitative study to explore the existence of boss ceiling effect and providing possible influential factors of brand downgrading attitude. The quantitative study empirically examines the relationships among undesired self, perceived risk, organizational culture balance, and downgrading attitude and intension.FindingsThe authors find that undesired self-congruence and perceived risk are positively related to the downgrading attitude. In addition, the culture balance directly affects the brand downgrading attitude negatively and also moderates the relationship between undesired self-congruence and downgrading attitude positively and the relationship between perceived risk and downgrading attitude negatively.Originality/valueThe authors contribute to both organizational culture research and symbolic consumption research by considering symbolic consumption behavior in organization context. It is of great practical implications for marketers of symbolic consumption to understand the downgrading behavior.

Effects of neighborhood environment, safety, and urban amenities on origins and destinations of walking behavior

ABSTRACT Walking increases physical activity and reduces obesity. Walking behavior is influenced by many different factors, including urban safety. This article studies origin and destination choices of walking behavior in Salt Lake City using GIS and statistical analyzes.We find that the origins, and destinations are influenced by different neighborhood environmental factors. Street connectivity and public parks increase the number of destinations, but have little impact on the number of origins. The number of origins increases in commercial areas with compact design. In terms of safety, we find that walking behavior is influenced by robbery events rather than traffic accidents. Furthermore, a geographical weighted regression model suggests that bus stops and population density have strong positive effects in high-density areas such as the downtown areas. Our study suggests that the current analytical framework on walkability is more suitable to explain the spatial distribution of walking trip destinations than the origins.

The role and robustness of the Gini coefficient as an unbiased tool for the selection of Gini genes for normalising expression profiling data

We recently introduced the Gini coefficient (GC) for assessing the expression variation of a particular gene in a dataset, as a means of selecting improved reference genes over the cohort (‘housekeeping genes’) typically used for normalisation in expression profiling studies. Those genes (transcripts) that we determined to be useable as reference genes differed greatly from previous suggestions based on hypothesis-driven approaches. A limitation of this initial study is that a single (albeit large) dataset was employed for both tissues and cell lines. We here extend this analysis to encompass seven other large datasets. Although their absolute values differ a little, the Gini values and median expression levels of the various genes are well correlated with each other between the various cell line datasets, implying that our original choice of the more ubiquitously expressed low-Gini-coefficient genes was indeed sound. In tissues, the Gini values and median expression levels of genes showed a greater variation, with the GC of genes changing with the number and types of tissues in the data sets. In all data sets, regardless of whether this was derived from tissues or cell lines, we also show that the GC is a robust measure of gene expression stability. Using the GC as a measure of expression stability we illustrate its utility to find tissue- and cell line-optimised housekeeping genes without any prior bias, that again include only a small number of previously reported housekeeping genes. We also independently confirmed this experimentally using RT-qPCR with 40 candidate GC genes in a panel of 10 cell lines. These were termed the Gini Genes. In many cases, the variation in the expression levels of classical reference genes is really quite huge (e.g. 44 fold for GAPDH in one data set), suggesting that the cure (of using them as normalising genes) may in some cases be worse than the disease (of not doing so). We recommend the present data-driven approach for the selection of reference genes by using the easy-to-calculate and robust GC.

Distribution of soil properties along forest-grassland interfaces: Influence of permanent environmental factors or land-use after-effects?

Soil properties vary spatially according to land use; both because land users have selected specific soil properties for specific land uses, and land uses modify the soil properties. However, permanent environment factors and land-use effects are unlikely to display the exact same spatial patterns. Study of the spatial and historical patterns of distribution of soil properties could help to separate between these two causes. In this aim, we studied 22 forest-grassland interfaces with controlled historical configurations in northeast France. In each land use (forest and grassland), three distances to the edge (edge, periphery and core) and two land-use histories (ancient and recent) were studied.Along forest-grassland interfaces, forests were usually located slightly upslope of grasslands, and mainly because this non-random topographic position the topsoil texture was significantly more silty in forests, and clayey in grasslands. After statistically controlling for the effects of topography and soil texture, we observed two main gradients of variation in soil properties according to the distance-to-edge (acidity in forest and nutrient content in grassland). In forest, pH and Ca dropped from the edges to the peripheries (15 m distance), while in grassland, C, N, P and Na sharply increased from the edges to the cores (25 m distance). These results demonstrate, through the edge effect, the strong influence of the land use on a part of soil properties. Furthermore, less than two centuries after grassland afforestation or deforestation, we observed that soil properties in recent forests and recent grasslands were respectively closer to their current land use than to their former land use. These results demonstrate a rapid change in soil properties after land-use change. However, recent forests and recent grasslands kept a legacy of soil texture from their former land use, respectively. Recent grasslands also kept a lower soil density, N and Na content compared to ancient grasslands.Hence, this study of forest-grassland interfaces show strong and short-scale relationships between land use and soil properties and suggest that they express both original choices of land users for specific soil properties and land-use after-effects. The non-random topographic position of the forest-grassland interfaces indicates a conscious choice of this positioning by the land users, for agronomic reasons. Beyond that, land use, through vegetation composition and management practices, also has a strong impact on soil properties. The fact that land-use changes affect most soil properties after only a few decades confirms the existence of land-use effects over time.

Creating and testing a GCP game in an asynchronous course environment: The game and future plans.

The National Institute of Health has mandated good clinical practice (GCP) training for all clinical research investigators and professionals. We developed a GCP game using the Kaizen-Education platform. The GCP Kaizen game was designed to help clinical research professionals immerse themselves into applying International Conference on Harmonization GCP (R2) guidelines in the clinical research setting through case-based questions. Students were invited to participate in the GCP Kaizen game as part of their 100% online academic Masters during the Spring 2019 semester. The structure of the game consisted of 75 original multiple choice and 25 repeated questions stemming from fictitious vignettes that were distributed across 10 weeks. Each question presented a teachable rationale after the answers were submitted. At the end of the game, a satisfaction survey was issued to collect player satisfaction data on the game platform, content, experience as well as perceptions of GCP learning and future GCP concept application. There were 71 total players who participated and answered at least one question. Of those, 53 (75%) answered all 100 questions. The game had a high Cronbach's alpha, and item analyses provided information on question quality, thus assisting us in future quality edits before re-testing and wider dissemination. The GCP Kaizen game provides an alternative method for mandated GCP training using principles of gamification. It proved to be a reliable and an effective educational method with high player satisfaction.

Modeling social influence using sequential stated adaptation experiments: A study of city trip itinerary choice

This paper introduces a model that captures the effect of social influence on decision makers’ choice behavior in the context of sequential stated adaptation experiments, in which a decision maker first chooses the alternative he/she personally likes best from an experimentally varied choice set and then, after being informed about the choice of a certain social network member, chooses again from the same choice set. Social influence represents the effect of the choices of one or more social network members in the same choice situation on the choice behavior of a decision maker. It is assumed to depend on a decision maker’s socio-demographics and personality traits, and the strength of the relationship with the social network member. The concept of choice consistency is introduced to reflect a respondent’s tendency to stick with his/her original choice in completing the sequential stated choice tasks. By accounting for this effect, a less biased estimate of social influence is obtained. Similarly, the model accounts for the case that the first choice of the respondent and the social network member’s choice are identical by introducing a correction factor to further reduce the bias in the estimated social influence. To access the validity of the model, the choice of city trip itinerary was chosen as an example. Decision makers’ personality traits and their relationship with the social network member were treated as latent variables. Therefore, first, exploratory and confirmatory factor analysis was carried out to investigate the reliability and validity of the constructed scales. Then a sequential estimation approach was employed to avoid confounding between decision makers’ preferences towards attributes and the effects of social influence and choice consistency. In the first stage, the taste parameters were estimated and then in the second stage the composition of social influence effect and choice consistency effect were estimated simultaneously. Results show that the model reproduced the observed data well. Social influence has a modest but significant effect on decision makers’ choice behavior; decision makers’ socio-demographics and personality traits, social network type as well as the relationship with social network members all have significant effects on social influence. The effect of choice consistency is also significant.

Decreasing surgical site infections in pediatric stoma closures

IntroductionGastrointestinal (GI) operations represent a significant proportion of the surgical site infection (SSI) burden in pediatric patients, resulting in significant morbidity. We have previously demonstrated that a GI bundle decreases SSI rates, length of stay (LOS), and hospital charges. Following this success, we hypothesized that by targeting the preoperative antibiotics for stoma closures based on organisms found in infected wounds, we could further decrease SSI rates. MethodsAs part of a broad quality improvement effort to reduce SSI rates, we reviewed the responsible pathogens and their sensitivities as well as the preoperative antibiotic used, and found that 15% of wound infections were caused by enterococcus. Based on this information, starting in April 2017, we changed the prior preoperative antibiotic cefoxitin to ampicillin-sulbactam, which more accurately targeted the prevalent pathogens from April 2017 to October 2018. ResultsThe baseline SSI rate for all stoma takedown patients was 21.4% (25 of 119). After bundle implementation, this decreased to 7.9% (17 of 221; p = 0.03) over a period of 2.5 years. Then, after changing the preoperative antibiotics, our rate of SSI decreased further to 2.2% (1 of 44; p = 0.039) over a period of 1.5 years. ConclusionSignificant reduction of SSI in GI surgery can be accomplished with several prevention strategies (our GI bundle). Then a change of the preoperative antibiotic choice, chosen based on causative wound infection organisms, may further decrease SSI rates. We recommend an institution specific analysis of wound infections and modification of preoperative antibiotics if the responsible organisms are resistant to the original antibiotic choice. Type of studyRetrospective cohort study. Level of evidenceLevel III.

Burnout in Obstetricians and Gynecologists.

Professional burnout threatens all high-functioning professionals and affects not only the individual, but, by extension, the patients they serve. The characteristics that make someone competitive for medical school, residency, or successful in academics or practice, make us particularly vulnerable to burnout: compulsive dedication to goals (and patients), motivation to succeed, self-reliance, leadership experience, delayed gratification, and others. Estimates of the prevalence of burnout in medicine vary widely but are consistently >40% and often as high as 75%. Obstetricians and gynecologists are not unique in suffering from burnout but do rank among the top medical specialties for the rate of professional burnout reported. When burnout is present, there is reduced job satisfaction, lower productivity, increased medical errors (and morbidity), degraded interpersonal interactions, and higher physician dropout rates. Career dissatisfaction, early retirement, and even regret surrounding the original choice of career are all common when burnout is present. There is a growing body of individual actions that can be taken to reduce or reverse the impact of burnout, but the first steps are to understand the causes and identify the symptoms.

Optimisation of the dipole-Coulomb approximation for high-l Rydberg states of polar molecules

ABSTRACTThe present work deals with the question of the origin choice to get the maximal accuracy of the dipole-Coulomb approximation in the theory of molecular Rydberg states with high orbital momentum l. Concerning birefringence in polar molecules, the question of adequate origin choice has first been raised in the classical work by Buckingham & Longuet-Higgins in 1968, where it has been taken into account that the dipole moment of a polar molecular core (cation) depends on the origin choice. This dependence also leads to inseparability of dipole and quadrupole corrections to the Rydberg electron spectra in polar molecules. In the present work a new option for the problem is proposed as applied to the dipole-Coulomb approximation. Considering a simplified model of a molecular core as a system of N effective fixed point charges, we show both analytically and numerically that the optimal choice of origin, at least for a linear core, is the geometric centre of the core. On the other hand, results of the present work as well as previous publications show that the problem raised by Buckingham and Longuet-Higgins does not have a universal solution.Abbreviations: RS: Rydberg state; RSs: Rydberg states; ZEKE: zero electron kinetic energy; MATI: mass-analysed threshold ionisation; QDT: quantum defect theory; DCA: dipole-Couloumb approximation; CD: centre of dipole; CC: centre of charge; GC: geometric centre; DCAGC: dipole-Couloumb approximation with origin in the geometric centre; DCACD: dipole-Couloumb approximation with origin in the centre of dipole