cssi/SciSciGPT-SciSciNet huggingface dataset:
Machine learning-assisted directed protein evolution with combinatorial libraries.

To reduce experimental effort associated with directed protein evolution and to explore the sequence space encoded by mutating multiple positions simultaneously, we incorporate machine learning into the directed evolution workflow. Combinatorial sequence space can be quite expensive to sample experimentally, but machine-learning models trained on tested variants provide a fast method for testing sequence space computationally. We validated this approach on a large published empirical fitness landscape for human GB1 binding protein, demonstrating that machine learning-guided directed evolution finds variants with higher fitness than those found by other directed evolution approaches. We then provide an example application in evolving an enzyme to produce each of the two possible product enantiomers (i.e., stereodivergence) of a new-to-nature carbene Si–H insertion reaction. The approach predicted libraries enriched in functional enzymes and fixed seven mutations in two rounds of evolution to identify variants for selective catalysis with 93% and 79% ee (enantiomeric excess). By greatly increasing throughput with in silico modeling, machine learning enhances the quality and diversity of sequence solutions for a protein engineering problem.
An iterative improvement approach for the discretization of numeric attributes in Bayesian classifiers

The Bayesian classifier is a simple approach to classification that produces results that are easy for people to interpret. In many cases, the Bayesian classifier is at least as accurate as much more sophisticated learning algorithms that produce results that are more difficult for people to interpret. To use numeric attributes with Bayesian classifier often requires the attribute values to be discretized into a number of intervals. We show that the discretization of numeric attributes is critical to successful application of the Bayesian classifier and propose a new method based on iterative improvement search. We compare this method to previous approaches and show that it results in significant reductions in misclassification error and costs on an industrial problem of troubleshooting the local loop in a telephone network. The approach can take prior knowledge into account by improving upon a user-provided set of boundary points, or can operate autonomously.
Pyrroloquinoline Quinone: Its Profile, Effects on the Liver and Implications for Health and Disease Prevention

Abstract Antioxidant supplementation can reverse hepatic steatosis, suggesting dietary antioxidants might have potential as therapeutics for nonalcoholic fatty liver disease (NAFLD) or nonalcoholic steatohepatitis (NASH). An extraordinarily potent dietary antioxidant is pyrroloquinoline quinone (PQQ). PQQ is a ubiquitous, natural, and essential bacterial cofactor found in soil, plants, and interstellar dust. The major source of PQQ in mammals is dietary; it is common in leafy vegetables, fruits, and legumes, especially soy, and is found in high concentrations in human and mouse breast milk. This chapter reviews chemical and biological properties enabling PQQ's pleiotropic actions, which include modulating multiple signaling pathways directly (NF-κB, JNK, JAK-STAT) and indirectly (Wnt, Notch, Hedgehog, Akt) to improve liver pathophysiology. The role of PQQ in the microbiome is discussed, as PQQ-secreting probiotics ameliorate oxidative stress–induced injury systemwide. A limited number of human trials are summarized, showing safety and efficacy of PQQ.
P32 Five Tips for Large-Scale Assessment of School Wellness Policies Using the WellSAT Scoring System

Background The AZ Health Zone administers Arizona's SNAP-Ed program. Our multi-year, statewide evaluations follow national evaluation standards, including accuracy and utility. The Rudd Center for Food Policy & Obesity developed the WellSAT to measure the quality of written SWPs, in consultation with an advisory board. The WellSAT has been updated twice to reflect changes to national regulations from the Healthy, Hunger-Free Kids Act. Objective To identify key characteristics of an accurate, useful system for large-scale SWP assessment. Study Design, Settings, Participants From October 2015—September 2018, the AZ Health Zone State Evaluation Team used a WellSAT scoring process to assess the quality of written school wellness policies (SWPs) from over 120 SNAP-Ed-qualified districts across Arizona's 15 counties. Local SNAP-Ed agencies submitted SWPs for WellSAT scoring and received back results and recommendations to use with districts. Measurable Outcome/Analysis We conducted a meta-evaluation to improve the WellSAT scoring process. Data from SWP meetings, evaluation meetings, debrief sessions, and interviews with Local SNAP-Ed Agencies were systematically analyzed to identify best practices for large-scale SWP assessment using the WellSAT. Results We identified five key characteristics of our scoring system. Use two consistent scorers. We enhanced accuracy by comparing results from two trained, independent scorers to catch errors and resolve discrepancies. Train scorers using state-specific guidelines. We further improved accuracy by developing a state-specific scoring template. Aim for rapid, responsive turnaround. We bolstered the utility of findings by generating results within four to eight weeks, or before district SWP meetings. Offer guidance on interpreting scores. We also enhanced utility by helping users understand how their scores compared to state averages and national trends. Create easy-to-use recommendations. We improved utility by providing users with editable, score-based recommendations on how to revise SWP language. Conclusion The accuracy and utility of large-scale SWP assessment can be enhanced using the five practices described above.
Pulsed flow-through auto-feeding beaker systems for the laboratory culture of juvenile freshwater mussels

Abstract Newly metamorphosed freshwater mussels are small and delicate, so that captive laboratory culture presents challenges for handling; for maintenance of suitable microhabitat, water quality, and food; and for avoidance of competitors and predators. To address these challenges, a new pulsed flow-through auto-feeding beaker system was developed for culturing juvenile mussels. In this system, groups of mussels were maintained in 300- to 1000-mL beakers with a thin layer of sand substrate. The water in the beakers was static except for pulses that were delivered every 1 or 2 h and that displaced about half of the water in each beaker per water cycle. A peristaltic pump delivered food to multiple mixing cells where the water was automatically mixed with food just before the water delivery. In testing this approach, newly metamorphosed mussels of 4 species were cultured in the system for 84 to 357 d. The sand and beakers were replaced weekly. Survival was high (>85% at day 84) for Lampsilis siliquoidea and Villosa iris, but relatively lower for Anodonta californiensis (29% at day 155) and Margaritifera falcata (23% at day 357). Growth rate ranged among the 4 species from 27 to 60 μm/d, with the slowest rate for M. falcata and fastest for A. californiensis. Overall, the new pulsed flow-through auto-feeding beaker system improved survival and growth of juvenile mussels versus other methods previously tested. Additionally, a simplified system for the water and food delivery was developed with a single mixing cell. The use of both systems indicate that they are suitable for laboratory experiments and for captive culture of juvenile mussels.
Residential Segregation, Neighborhood Health Care Organizations, and Children's Health Care Utilization in the Phoenix Urbanized Area:

Research has demonstrated health care consequences of racial/ethnic residential segregation. Here, I test one possible mechanism—the distribution of community health care organizations and service ...
Real-Time Optimization: How to Change Setpoints in Pharmaceutical Manufacturing

Real-time optimization (RTO) is an important requirement of pharmaceutical production processes. Production processes are operated by adjusting the setpoints of one or more individual unit operations, either to optimize a given objective function or to satisfy externally imposed constraints. Most commonly, setpoints are changed based on inputs from other components of a larger real-time process management (RTPM) system. Since setpoint changes may have knock-on effects elsewhere in the process, it is important to treat setpoint changes not as an isolated activity but as part of a more comprehensive process management suite. This chapter describes common manufacturing scenarios that require setpoints to be changed or optimized, discusses the trade-offs between static optimization based on a priori flowsheet simulation and dynamic optimization based on current process data, and describes good practices in such setpoint transitions.
Fighting Stigma by Engaging Persons Living with Dementia in Research.

Edited by Jacquelyn H. Flaskerud, RN, PhD, FAAN School of Nursing, University of California, Los Angeles, California, USA Although I have not always had an interest in dementia, personal, professio...
An Initial Julia Simulation Approach to Material Handling Operations from Motion Captured Data

Performing modeling simulations with visualization and control can be rather difficult for dynamical models or other diverse applications. This work demonstrates the utility of the Julia programming language to solve this problem by being able to keep a simple condensed code and creating a powerful visual model with various controls. The simulation application is based on material handling tasks that are analyzed for human fatigue from repetitive operations. The aim is to detect human motions when performing the tasks and predict fatigue levels associated with these activities. The Julia simulation development addresses developing a computational solution to generate human subjects performing material handling operations synthetically. With the use of several Julia packages, the simulation development used the data from the Qualisys Motion Capture Systems and rendered each of the 41 points of data of a human subject performing lifting and lowering repetitive task.
Implementation of an Online Multimedia Pediatric Tracheostomy Care Module for Healthcare Providers

OBJECTIVES/HYPOTHESIS To investigate the effect of a multimedia educational module on provider attitudes toward pediatric tracheostomy care. We also describe the process of module development and dissemination at an academic children's hospital. STUDY DESIGN Prospective observational study. METHODS The pediatric airway committee at an urban tertiary care center developed a multimedia pediatric tracheostomy care module. Nurses, respiratory therapists, as well as resident, fellow, and attending physicians caring for pediatric patients with tracheostomies were eligible. Managers and clinical supervisors from various units recruited participants to complete the pediatric tracheostomy care electronic module and pre- and postassessment knowledge quizzes and surveys. Provider confidence was analyzed using Kruskal-Wallis H-test and Mann-Whitney U-test, and paired t-test was used to compare pre- and postmodule quiz scores. RESULTS A total of 422 participants completed the module. A total of 275 participants completed the premodule survey, 385 completed the premodule quiz, 253 completed the postmodule survey, and 233 completed the postmodule quiz. Participants included providers in the neonatal intensive care unit, pediatric intensive care unit, pediatric emergency department, and pediatric wards. Postmodule surveys demonstrated a significant reduction in the average percentage of participants indicating lack of confidence with regards to changing an established tracheostomy, responding to accidental decannulation of established tracheostomy, and responding to accidental decannulation of fresh tracheostomy (P < .001). Average quiz scores increased by 5.6 points from 83.0% to 88.6% (P < .00001). CONCLUSIONS A multimedia educational module can improve provider perception of their knowledge and confidence surrounding pediatric tracheostomy management. LEVEL OF EVIDENCE 3 Laryngoscope, 131:1893-1901, 2021.
Interleaved practice benefits implicit sequence learning and transfer

Compared to blocked practice, interleaved practice of different tasks leads to superior long-term retention despite poorer initial acquisition performance. This phenomenon, the contextual interference effect, is well documented in various domains but it is not yet clear if it persists in the absence of explicit knowledge in terms of fine motor sequence learning. Additionally, while there is some evidence that interleaved practice leads to improved transfer of learning to similar actions, transfer of implicit motor sequence learning has not been explored. The present studies used a serial reaction time task where participants practiced three different eight-item sequences that were either interleaved or blocked on Day 1 (training) and Day 2 (testing). In Experiment 1, the retention of the three training sequences was tested on Day 2 and in Experiment 2, three novel sequences were performed on Day 2 to measure transfer. We assessed whether subjects were aware of the sequences to determine whether the benefit of interleaved practice extends to implicitly learned sequences. Even for participants who reported no awareness of the sequences, interleaving led to a benefit for both retention and transfer compared to participants who practiced blocked sequences. Those who trained with blocked sequences were left unprepared for interleaved sequences at test, while those who trained with interleaved sequences were unaffected by testing condition, revealing that learning resulting from blocked practice may be less flexible and more vulnerable to testing conditions. These results indicate that the benefit of interleaved practice extends to implicit motor sequence learning and transfer.
Proteomics analysis reveals digestion-resistant proteins from colostrum are associated with inflammatory and cytotoxic responses in intestinal epithelial cells

Background Though human milk feeding reduces the risk of necrotizing enterocolitis (NEC) in preterm infants compared with formula feeding, the exact risk reduction mechanism remains unknown. As NEC occurs at the distal small intestines where digestion has occurred, we applied proteomics to examine the extent to which colostrum proteins survive simulated infant in vitro digestion, and thus have potential to exert biological function. Methods Ten preterm colostrum samples were left undigested or in vitro-digested, and lipopolysaccharide (LPS) binding protein, soluble cluster of differentiation 14, and tumor necrosis factor (TNF) receptors I and II were measured using ELISA in all undigested and in vitro-digested samples. Fully differentiated Caco-2 cells were exposed to digested colostrum samples prior to stimulation with LPS, TNF, or no stimulation. Inflammation (interleukin 8) and cytotoxicity (lactate dehydrogenase) were measured. Proteomic analyses of undigested and in vitro-digested samples were done using mass spectrometry. Results We found that most proteins in colostrum are significantly, if not completely, degraded following in vitro digestion. We found select individual and combination digestion-resistant proteins that were positively correlated with LPS- and TNF-induced inflammation. Conclusions These results indicate the importance of considering the extent to which specific dietary compounds survive digestion to reach their site of claimed action (distal intestines), and that some digestion-resistant proteins may be contributing towards "low grade" inflammation that is necessary to promote intestinal growth and maturation during early infancy. This work provides the most detailed understanding of human milk protein degradation with simulated infant in vitro digestion to date. This article is protected by copyright. All rights reserved.
New Brands Versus Brand Extensions, Attitudes Versus Choice: Experimental Evidence for Theory and Practice

The current study compares better-fitting and worse-fitting new brand names and brand extensions on brand attitudes and choice shares across situations that differ in terms of the amount of product information available and consumer knowledge of the target product category (which had limited effects), 35[emsp4 ]mm cameras (choice-set competitors Nikon and Minolta). While brand extensions and better-fitting brands generally enjoyed more positive brand attitudes and larger choice shares, effects were moderated by product information. When information was limited to brand name and price, the better-fitting brand extension (Sony) commanded more share than did the better-fitting new brand (Optix) which in turn commanded more share than did either the worse-fitting extension (Nike) or the worse-fitting new brand (Topix). But when information on product features was added, target brands were chosen similarly across brand names where the better-fitting new brand Optix garnered slightly (non-significantly; 5%) more share than the better-fitting extension Sony. This weak preference was reversed, however, in the attitude data where Sony was rated significantly higher in liking than Optix. Two focal conclusions emerge. First, new brands can perform as well as or better than brand extensions when consumers process product information. In this study, brand-extension advantages were confined to situations of limited information processing and better fit. Second, since branding effects differed across attitudes and choice, researchers hoping to duplicate in the laboratory the types of branding effects likely to occur in the marketplace may want to expand their traditional focus on attitudes to include choice.
Sex, Fear, and Public Health Policy

Looking into the AIDS abyss in the mid-1980s, public health officials sometimes succumbed to the same impulses—notably, panic and scapegoating—that activated politicians, judges, and the public itself. Among the best-known results of these impulses were city-by-city efforts to shut down gay bathhouses. No one disputed that sexual activity went on in the bathhouses, but it was—and remains—unclear whether closing them would help stop the transmission of HIV, hinder that effort, or have no net effect. Gay Bathhouses and Public Policy, a collection of essays on this topic, comes two decades after the hardest-fought bathhouse closure battles. William J. Woods and Diane Binson, the book’s editors (and contributors), have skillfully amassed a group of works that provides a mix of historical depth, reportorial analysis, statistical research, and legal background to the battle over the bathhouses. The authors’ stated purpose is to fill a void in knowledge, information, and understanding of the bathhouse question. The bathhouse wars are thereby given historical and cultural context that is perhaps only possible twenty years after these battles were conducted. In this mission, the book succeeds. The volume, simultaneously published as two issues of the Journal of Homosexuality, collects legal, public health, and reportorial papers about the controversy over gay bathhouses and their role in the prevention or spread of HIV.
IEEE PROJECT 802: LOCAL AREA NETWORK STANDARD – A March 1982 Status Report

Abstract This paper describes Project 802 of the Computer Society of the Institute for Electrical and Electronic Engineers (IEEE)1. Project 802 is defining a standard for local area networks in which microprocessor controlled terminals and other devices are coupled on a peer-to-peer basis. The paper provides a brief history and rationale for the effort and an overview of the current draft standard.
Exponential Decay Results for Semilinear Parabolic PDE with $$C^0$$ Potentials: A “Mean Value” Approach

The asymptotic behavior of some semilinear parabolic PDEs is analyzed by means of a “mean value” property. This property allows us to determine, by means of appropriate a priori estimates, some exponential decay results for suitable global solutions. We also apply the method to investigate a well-known finite time blow-up result. An application is given to a one-dimensional semilinear parabolic PDE with boundary degeneracy. Our results shed further light onto the problem of determining initial data for which the corresponding solution is guaranteed to exponentially decay to zero or blow-up in finite time.
N-SULFONYL IMINES : USEFUL SYNTHONS IN STEREOSELECTIVE ORGANIC SYNTHESIS

Until recently, N-sulfonyl imines had found only limited and sporadic use in organic synthesis. During the past decade, however, it has become increasingly clear that these species are valuable synthons and are capable of undergoing many unique transformations. A comprehensive review of the chemistry of these compounds is presented here with particular emphasis on their applications in stereoselective processes. Methods for preparing N-sulfonyl imines are outlined, along with a survey of their uses in a wide range of addition, pericyclic and cycloaddition reactions.
Solving POMDPs using quadratically constrained linear programs

Developing scalable algorithms for solving partially observable Markov decision processes (POMDPs) is an important challenge. One approach that effectively addresses the intractable memory requirements of POMDP algorithms is based on representing POMDP policies as finite-state controllers. In this paper, we illustrate some fundamental disadvantages of existing techniques that use controllers. We then propose a new approach that formulates the problem as a quadratically constrained linear program (QCLP), which defines an optimal controller of a desired size. This representation allows a wide range of powerful nonlinear programming algorithms to be used to solve POMDPs. Although QCLP optimization techniques guarantee only local optimality, the results we obtain using an existing optimization method show significant solution improvement over the state-of-the-art techniques. The results open up promising research directions for solving large POMDPs using nonlinear programming methods.
Mechanistic Basis for Regioselection and Regiodivergence in Nickel-Catalyzed Reductive Couplings

ConspectusThe control of regiochemistry is a considerable challenge in the development of a wide array of catalytic processes. Simple π-components such as alkenes, alkynes, 1,3-dienes, and allenes are among the many classes of substrates that present complexities in regioselective catalysis. Considering an internal alkyne as a representative example, when steric and electronic differences between the two substituents are minimal, differentiating among the two termini of the alkyne presents a great challenge. In cases where the differences between the alkyne substituents are substantial, overcoming those biases to access the regioisomer opposite that favored by substrate biases often presents an even greater challenge.Nickel-catalyzed reductive couplings of unsymmetrical π-components make up a group of reactions where control of regiochemistry presents a challenging but important objective. In the course of our studies of aldehyde–alkyne reductive couplings, complementary solutions to challenges in regioco...
Laplace Approximation in High-Dimensional Bayesian Regression

We consider Bayesian variable selection in sparse high-dimensional regression, where the number of covariates p may be large relative to the sample size n, but at most a moderate number q of covariates are active. Specifically, we treat generalized linear models. For a single fixed sparse model with well-behaved prior distribution, classical theory proves that the Laplace approximation to the marginal likelihood of the model is accurate for sufficiently large sample size n. We extend this theory by giving results on uniform accuracy of the Laplace approximation across all models in a high-dimensional scenario in which p and q, and thus also the number of considered models, may increase with n. Moreover, we show how this connection between marginal likelihood and Laplace approximation can be used to obtain consistency results for Bayesian approaches to variable selection in high-dimensional regression.
DeepOrgan: Multi-level Deep Convolutional Networks for Automated Pancreas Segmentation

Automatic organ segmentation is an important yet challenging problem for medical image analysis. The pancreas is an abdominal organ with very high anatomical variability. This inhibits previous segmentation methods from achieving high accuracies, especially compared to other organs such as the liver, heart or kidneys. In this paper, we present a probabilistic bottom-up approach for pancreas segmentation in abdominal computed tomography CT scans, using multi-level deep convolutional networks ConvNets. We propose and evaluate several variations of deep ConvNets in the context of hierarchical, coarse-to-fine classification on image patches and regions, i.e. superpixels. We first present a dense labeling of local image patches via P-ConvNet and nearest neighbor fusion. Then we describe a regional ConvNet R1-ConvNet that samples a set of bounding boxes around each image superpixel at different scales of contexts in a "zoom-out" fashion. Our ConvNets learn to assign class probabilities for each superpixel region of being pancreas. Last, we study a stacked R2-ConvNet leveraging the joint space of CT intensities and the P-ConvNet dense probability maps. Both 3D Gaussian smoothing and 2D conditional random fields are exploited as structured predictions for post-processing. We evaluate on CT images of [InlineEquation not available: see fulltext.] patients in 4-fold cross-validation. We achieve a Dice Similarity Coefficient of 83.6±6.3% in training and 71.8±10.7% in testing.
The long-run evolution of energy prices

In this paper the author examines the long-run behavior of oil, coal, and natural gas prices, using up to 127 years of data, and address the following questions: What does over a century of data tell us about the stochastic dynamics of price evolution, and how it should be modeled? Can models of reversion to stochastically fluctuating trend lines help forecast prices over horizons of 20 years or more? And what doe the answers to these questions tell about investment decisions that are dependent on prices and their stochastic evolution?
A Golden Era for Astronomy: The Advent of CCDS and Infrared Arrays

The advent of solid-state imaging devices transformed astronomy. Beginning with the introduction into astronomy of charge-coupled devices in 1976, followed a decade later by infrared arrays, astronomers gained access to near-perfect imaging devices. The consequences have been nothing short of revolutionary, perhaps especially so in the infrared. Witness, for example, the spectacular pictures from the Hubble Space Telescope cameras, or the impressive infrared imagery from the 2MASS project. Within the last decade CCD formats deployed or planned for use in ground-based cameras have become huge. Infrared mosaics, stimulated by the Next Generation Space Telescope, are coming soon. In addition, new technologies such as CMOS (Complementary Metal Oxide Semiconductors) and STJs (Superconductiong Tunnel Junctions) are being developed and the future of astronomical detectors looks very exciting, especially in an era of giant telescopes performing at their diffraction-limit.
Normalizing Foucault? A Rhizomatic Approach to Plateaus in Anglophone Educational Research

This paper offers a rhizomatic reading of Foucault scholarship in anglophone educational research. It delineates unique parameters of an educational field, the conditions of receptivity for Foucault's work, and identifies three temporary plateau-formations that have erupted in educational research. Indebted to (non-formulaic) principles of connectivity and heterogeneity, multiplicity, and asignifying ruptures the analysis brings to notice the recombinatorial attributes of the discipline of education through attention to what is encamped and what seeps in debates over his work.
Defeasible Decisions: What the Proposal Is and Isn't

Publisher Summary This chapter discusses defeasible reasoning for decisions, which is the natural extension of philosophers' defeasible practical reasoning about action. The difference in it is that the arguments for actions are quantitative, often invoking expected utility calculations. In practical reasoning, reasoning about action is qualitative. If an act achieves a goal, that is a reason for performing that act. If an act achieves a goal but also invokes a penalty and that penalty is more undesirable than the goal itself, then that may be the reason of not performing the act. However, qualitative practical reasoning is a very weak way of analyzing tradeoffs. It does not take into account known risks of actions, that is, the known probabilities of acts achieving various effects. The chapter presents a quantitative version of defeasible reasoning about decisions. An act achieves an effect with known probability and there are independent reasons for the utilities of each of the resulting states. By weighing these independent utilities by their respective probabilities, an argument for the utility of the act is produced. With different independent reasons for the utilities of resulting states, one gets different arguments. With different accounting of the possible results of an act, different arguments are produced. Reasons can be written in an existing formalism for defeasible reasoning in such a way that those arguments that justify their conclusions are exactly those arguments that one would consider compelling among the multitude of potentially conflicting arguments.
Automating computer bottleneck detection with belief nets

We describe an application of belief networks to the diagnosis of bottlenecks in computer systems. The technique relies on a high-level functional model of the interaction between application workloads, the Windows NT operating system, and system hardware. Given a workload description, the model predicts the values of observable system counters available from the Windows NT performance monitoring tool. Uncertainty in workloads, predictions, and counter values are characterized with Gaussian distributions. During diagnostic inference, we use observed performance monitor values to find the most probable assignment to the workload parameters. In this paper we provide some background on automated bottleneck detection, describe the structure of the system model, and discuss empirical procedures for model calibration and verification. Part of the calibration process includes generating a dataset to estimate a multivariate Gaussian error model. Initial results in diagnosing bottlenecks are presented.
Integral traces of weak Maass forms of genus zero odd prime level

Duke and the second author defined a family of linear maps from spaces of weakly holomorphic modular forms of negative integral weight and level 1 into spaces of weakly holomorphic modular forms of half-integral weight and level 4 and showed that these lifts preserve the integrality of Fourier coefficients. We show that the generalization of these lifts to modular forms of genus 0 odd prime level also preserves the integrality of Fourier coefficients.
A new value‐added strategy for the US beef industry: The case of US Premium Beef Ltd

US Premium Beef Ltd is a cooperative partnership between all segments of the beef industry value chain, affording each segment an interest in the key stages of beef production and processing, as well as an equal share of the financial risks and rewards. This “value‐added” strategy is accomplished through vertical integration and adding a quality‐based pricing structure to more closely link beef producers and consumers. The case study is an example of supply chain management as a strategic response to a mature industry. It also exemplifies how ownership structure of the firm, particularly the emergence of new‐generation cooperatives, is employed as a strategic factor in developing a new competitive approach in an industry characterized by sales decline and aggressive competition from substitute products such as poultry and pork.
Minimizing the Aggregate Movements for Interval Coverage

We consider an interval coverage problem. Given n intervals of the same length on a line L and a line segment B on L, we want to move the intervals along L such that every point of B is covered by at least one interval and the sum of the moving distances of all intervals is minimized. As a basic geometry problem, it has applications in mobile sensor barrier coverage in wireless sensor networks. The previous work solved the problem in $$O(n^2)$$O(n2) time. In this paper, by discovering many interesting observations and developing new algorithmic techniques, we present an $$O(n\log n)$$O(nlogn) time algorithm. We also show an $$\varOmega (n\log n)$$Ω(nlogn) time lower bound for this problem, which implies the optimality of our algorithm.
Tax Policy Under Keeping Up with the Joneses and Imperfectly Competitive Product Markets

This paper examines the optimal (first-best) fiscal policy in a stochastic representative agent model that exhibits a ``keeping up with the Joneses'' utility function and imperfectly competitive product markets. We find that the optimal labor tax is a constant, whose sign is determined by the relative strength of consumption externality and monopoly power. Moreover, the optimal capital tax is unambiguously negative and affects the economy countercyclically. Our analysis shows that models with capital accumulation, imperfect competition, and ``keeping up with the Joneses'' preferences call for traditional Keynesian demand-management policies that are designed to mitigate business cycle fluctuations
The Value of Heterogeneous Property Rights and the Costs of Water Volatility

The system of prior appropriation in the Western Unites States prioritizes property rights for water based on the establishment of beneficial use, creating a hierarchy where rights initiated first are more secure. I estimate the demand for security in water rights through their capitalization in agricultural property markets in the Yakima River Basin, a major watershed in Washington State. All water rights are satisfied in an average year, so the relative value of secure property rights is a function of water supply volatility and the costs of droughts are predominantly born by those with weak rights. In aggregate, security in water rights does not capitalize into property values at the irrigation district level; however, there is heterogeneity in the premium for secure water rights. The lack of a premium for district-level water security is robust to a variety of econometric methods to account for correlated district unobservables, and the null result produces an economically significant upper bound on the value to water security for the district. The ability for farmers to adapt to water supply volatility, as well as expectations about water markets and government infrastructure investment, are leading explanations for the lack of an aggregate premium. These explanations are supported by the pattern of heterogeneity in the water security premium.
Determination of fluoride: Procedure based upon diffusion of hydrogen fluoride☆

Abstract The principle of fluoride determination by diffusion of hydrogen fluoride in Conway-type cells made of polypropylene has been applied to the determination of fluoride in plasma, liver, muscle, calcified tissues, urine, and saliva. Methods for preparation of the low fluoride containing biological specimens by precipitation of proteins with perchloric acid and analysis of the supernatant liquid are described. The results of fluoride analyses by diffusion compare well with those obtained by microdistillation. The diffusion method for fluoride analysis is more simple than distillation procedures.
Environmental Regulation and Competitiveness: Evidence from Trade and Production in the Manufacturing Sector

Previous empirical studies of the pollution haven hypothesis (PHH) have not reached a consistent conclusion. The existing literature is primarily based on anecdotes and scattered case studies. This study analyzes the trade flows and composition change of the most polluting industries in manufacturing sectors among countries in order to offer a more general conclusion. This study finds that stricter environmental regulation stringency decreases the net export and production share of the most polluting production, which provides the evidence for pollution haven effect (PHE). However, we find no evidence to support PHH. Contrary, we find stricter environmental regulation stringency corresponds to larger net export and polluting production as trade openness increases. We also find that the ability to innovate in environmental-related technology creates a comparative advantage in polluting production. This finding implies that governments do not have to constrain their policies on the tradeoff between pollution control and international competitiveness since the innovative ability may both obtain the goals of pollution control and strengthening international competitiveness.
Protein quality control in bacterial cells: integrated networks of chaperones and ATP-dependent proteases.

It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approaches 300–400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1, 2, 3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vectorial synthesis process. Amino acids are added to a growing nascent chain at the rate of ∼5 residues per sec, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol ∼1 min before its C-terminus and be free to begin the folding process.
Benchmarking Public Policy : Methodological Insights from Measurement of School Based Management

This working paper presents a benchmarking analysis of School Based Management (SBM) using empirical data from the Philippines. School based management is widely used as a policy tool in many countries that seek to improve the quality of service delivery through decentralization. School based management typically takes many years to have an impact on educational outcomes, but policy makers need to know sooner how well the policy is being implemented. The paper extends the well-known Rasch methodology from the literature on student achievement, including the Programme for International Student Assessment, to the measurement of the implementation of school based management by computing a Rasch measure of the implementation of school based management. To test whether the resulting benchmarked measure is plausible and has practical policy value, the measure is tested for correlations with standardized measures of personality and political skills of school principals, developed in the psychology and political science literatures. The paper will be useful for readers interested in studying school based management as well as those interested more generally in the methodology of benchmarking implementation of public policy where the ultimate results are subject to long implementation periods. The methodology presented in this paper can be applied to enhance the rigor of the ongoing Systems Approach for Better Education Results (SABER) exercise to benchmark educational policies in various domains. That exercise is set to become one of the flagship policy analytical tools being developed by the World Bank and partner agencies.
“Propertyzing” The Electromagnetic Spectrum: Why It’s Important, And How To Begin

For the past century the telecommunications sector of the U.S. Economy has been an arena of substantial technological change and improvement. In 1900 telephony was in its infancy, and the first over-the-air broadcast of human speech had yet to be made. By the end of the century, telephone, radio, and television were commonplace but highly valued parts of American lives, while both wireline- and spectrum-based telecommunications had become essential to all aspects of the business world.
Temporal Evolution Of Thermal Emission From Relativistically Expanding Plasma

Propagation of photons in relativistically expanding plasma outflows characterized by steady Lorentz factor Γ is considered. Photons that are injected in regions of high optical depth are advected with the flow until they escape at the photosphere. Below the photosphere, the photons are coupled to the plasma via Compton scattering. I show here that as a result of the slight misalignment of the scattering electrons' velocity vectors, the (local) comoving photon energy decreases with radius as '(r) ∝ r−2/3. This mechanism dominates the photon cooling in scenarios of faster adiabatic cooling of the electrons. I then show that the photospheric radius of a relativistically expanding plasma wind strongly depends on the angle to the line of sight, θ. For θ Γ−1, the photospheric radius is θ-independent, while for θ Γ−1, rph(θ) ∝ θ2. I show that the θ-dependence of the photosphere implies that for flow parameters characterizing gamma-ray bursts (GRBs), thermal photons originating from below the photosphere can be observed up to tens of seconds following the inner engine activity decay. I calculate the probability density function P(r,θ) of a thermal photon to escape the plasma at radius r and angle θ. Using this function, I show that following the termination of the internal photon injection mechanism, the thermal flux decreases as FobBB(t) ∝ t−2, and that the decay of the photon energy with radius results in a power-law decay of the observed temperature, Tob(t) ∝ t−2/3 at early times, which changes to t−1/2 later. Detailed numerical results are in very good agreement with the analytical predictions. I discuss the consequences of this temporal behavior in view of the recent evidence for a thermal emission component observed during the prompt emission of GRBs.
Vaporization thermodynamics and heat capacities of Ti5Ge3 and Ti6Ge5

Abstract Thermodynamic stabilities of titanium germanides Ti5Ge3 and Ti6Ge5 have been studied by means of high-temperature Knudsen effusion mass spectrometry (KEMS) and differential scanning calorimetry (DSC). Thermodynamic activities of Ti and Ge have been measured over the two-phase mixtures of Ti5Ge3+Ti6Ge5 in a temperature range of ca. 1680–1880 K by direct comparison with solid Ti and liquid Ge metals. The standard free energies of formation of Ti5Ge3 and Ti6Ge5 at high temperature were determined from the activity data. Heat capacities of Ti5Ge3 and Ti6Ge5 were measured by DSC in the temperature region 300–700 K. Standard enthalpies of formation of Ti5Ge3 and Ti6Ge5 at 298 K were calculated by the third-law method with the use of estimated absolute entropy and high-temperature heat capacity data. The results obtained are: 1 8 Ti5Ge3, −69.8±5 kJ; 1 11 Ti6Ge5, −70.1±5 kJ. The results obtained in this work are compared with previous estimates and measurements.
A Perspective on Graphs and Access Control Models

There would seem to be a natural connection between graphs and information security. This is particularly so in the arena of access control and authorization. Research on applying graph theory to access control problems goes back almost three decades. Nevertheless it is yet to make its way into the mainstream of access control research and practice. Much of this prior research is based on first principles, although more recently there have been significant efforts to build upon existing graph theory results and approaches. This paper gives a perspective on some of the connections between graphs and their transformations and access control models, particularly with respect to the safety problem and dynamic role hierarchies.
Supersparse linear integer models for predictive scoring systems

Scoring systems are classification models that make predictions using a sparse linear combination of variables with integer coefficients. Such systems are frequently used in medicine because they are interpretable; that is, they only require users to add, subtract and multiply a few meaningful numbers in order to make a prediction. See, for instance, these commonly used scoring systems: (Gage et al. 2001; Le Gall et al. 1984; Le Gall, Lemeshow, and Saulnier 1993; Knaus et al. 1985). Scoring systems strike a delicate balance between accuracy and interpretability that is difficult to replicate with existing machine learning algorithms. Current linear methods such as the lasso, elastic net and LARS are not designed to create scoring systems, since regularization is primarily used to improve accuracy as opposed to sparsity and interpretability (Tibshirani 1996; Zou and Hastie 2005; Efron et al. 2004). These methods can produce very sparse models through heavy regularization or feature selection methods (Guyon and Elisseeff 2003); however, feature selection often relies on greedy optimization and cannot guarantee an optimal balance between sparsity and accuracy. Moreover, the interpretability of scoring systems requires integer coefficients, which these methods do not produce. Existing approaches to interpretable modeling include decision trees and lists (Ruping 2006; Quinlan 1986; Rivest 1987; Letham et al. 2013). We introduce a formal approach for creating scoring systems, called Supersparse Linear Integer Models (SLIM). SLIM produces scoring systems that are accurate and interpretable using a mixed-integer program (MIP) whose objective penalizes the training error, L0-norm and L1-norm of its coefficients. SLIM can create scoring systems for datasets with thousands of training examples and tens to hundreds of features - larger than the sizes of most studies in medicine, where scoring systems are often used.
Crystal growth of two new photoluminescent oxides: Sr3Li6Nb2O11 and Sr3Li6Ta2O11.

Single crystals of Sr3Li6M2O11 (M = Nb, Ta) were grown out of a high-temperature Sr(OH)2/LiOH/KOH flux. The single crystal X-ray diffraction data were indexed to the orthorhombic Pmma system, with ...