cssi/SciSciGPT-SciSciNet huggingface dataset:
Fertility of Pedicellate Spikelets in Sorghum Is Controlled by a Jasmonic Acid Regulatory Module

As in other cereal crops, the panicles of sorghum (Sorghum bicolor (L.) Moench) comprise two types of floral spikelets (grass flowers). Only sessile spikelets (SSs) are capable of producing viable grains, whereas pedicellate spikelets (PSs) cease development after initiation and eventually abort. Consequently, grain number per panicle (GNP) is lower than the total number of flowers produced per panicle. The mechanism underlying this differential fertility is not well understood. To investigate this issue, we isolated a series of ethyl methane sulfonate (EMS)-induced multiseeded (msd) mutants that result in full spikelet fertility, effectively doubling GNP. Previously, we showed that MSD1 is a TCP (Teosinte branched/Cycloidea/PCF) transcription factor that regulates jasmonic acid (JA) biosynthesis, and ultimately floral sex organ development. Here, we show that MSD2 encodes a lipoxygenase (LOX) that catalyzes the first committed step of JA biosynthesis. Further, we demonstrate that MSD1 binds to the promoters of MSD2 and other JA pathway genes. Together, these results show that a JA-induced module regulates sorghum panicle development and spikelet fertility. The findings advance our understanding of inflorescence development and could lead to new strategies for increasing GNP and grain yield in sorghum and other cereal crops.
Seed Germination of Pieris floribunda: Influence of Light and Temperature

Abstract Seeds of Pieris floribunda (Pursh ex Sims) Benth. and Hook, (mountain andromeda) were germinated at 25°C (77°F) or an 8/16 hr thermoperiod of 25°/15°C (77°/59°F) with daily photoperiods of...
Reliability of administrative data to identify sexually transmitted infections for population health: a systematic review.

Introduction International Classification of Diseases (ICD) codes in administrative health data are used to identify cases of disease, including sexually transmitted infections (STIs), for population health research. The purpose of this review is to examine the extant literature on the reliability of ICD codes to correctly identify STIs. Methods We conducted a systematic review of empirical articles in which ICD codes were validated with respect to their ability to identify cases of chlamydia, gonorrhoea, syphilis or pelvic inflammatory disease (PID). Articles that included sensitivity, specificity and positive predictive value of ICD codes were the target. In addition to keyword searches in PubMed and Scopus databases, we further examined bibliographies of articles selected for full review to maximise yield. Results From a total of 1779 articles identified, only two studies measured the reliability of ICD codes to identify cases of STIs. Both articles targeted PID, a serious complication of chlamydia and gonorrhoea. Neither article directly assessed the validity of ICD codes to identify cases of chlamydia, gonorrhoea or syphilis independent of PID. Using ICD codes alone, the positive predictive value for PID was mixed (range: 18%–79%). Discussion and conclusion While existing studies have used ICD codes to identify STI cases, their reliability is unclear. Further, available evidence from studies of PID suggests potentially large variation in the accuracy of ICD codes indicating the need for primary studies to evaluate ICD codes for use in STI-related public health research.
Rushed Innovation: Evidence from Drug Licensing

We study the drug licensing behavior (acquisition of rights for developing drugs) of large pharmaceutical firms in the aftermath of large negative shocks to their pipelines, phase 3 failures (P3Fs)...
On the real stability radius of sparse systems

Abstract In this paper, we study robust stability of sparse LTI systems using the stability radius (SR) as a robustness measure. We consider real perturbations with an arbitrary and pre-specified sparsity pattern of the system matrix and measure their size using the Frobenius norm. We formulate the SR problem as an equality-constrained minimization problem. Using the Lagrangian method for optimization, we characterize the optimality conditions of the SR problem, thereby revealing the relation between an optimal perturbation and the eigenvectors of an optimally perturbed system. Further, we use the Sylvester equation based parametrization to develop a penalty based gradient/Newton descent algorithm which converges to the local minima of the optimization problem. Finally, we illustrate how our framework provides structural insights into the robust stability of sparse networks.
On the graph Laplacian and the rankability of data

Abstract Recently, Anderson et al. (2019) proposed the concept of rankability, which refers to a dataset's inherent ability to produce a meaningful ranking of its items. In the same paper, they proposed a rankability measure that is based on an integer program for computing the minimum number of edge changes made to a directed graph in order to obtain a complete dominance graph, i.e., an acyclic tournament graph. In this article, we prove a spectral-degree characterization of complete dominance graphs and apply this characterization to produce a new measure of rankability that is cost-effective and more widely applicable. We support the details of our algorithm with several results regarding the conditioning of the Laplacian spectrum of complete dominance graphs and the Hausdorff distance between their Laplacian spectrum and that of an arbitrary directed graph with weights between zero and one. Finally, we analyze the rankability of datasets from the world of chess and college football.
Efficient parametric frequency conversions in lithium niobate nanophotonic chips

We demonstrate in a periodically-poled nanowaveguide nanowaveguide second harmonic generation with efficiency over 2200% W−1cm−2, difference frequency generation over 4.5 THz, and multichannel photon pair generation with a coincidence to accidental ratio as high as 600.
Who Is in Your Top Three? Optimizing Learning in Elections with Many Candidates

Elections and opinion polls often have many candidates, with the aim to either rank the candidates or identify a small set of winners according to voters’ preferences. In practice, voters do not provide a full ranking; instead, each voter provides their favorite K candidates, potentially in ranked order. The election organizer must choose K and an aggregation rule. We provide a theoretical framework to make these choices. Each K-Approval or K-partial ranking mechanism (with a corresponding positional scoring rule) induces a learning rate for the speed at which the election recovers the asymptotic outcome. Given the voter choice distribution, the election planner can thus identify the rate optimal mechanism. Earlier work in this area provides coarse order-of-magnitude guaranties which are not sufficient to make such choices. Our framework further resolves questions of when randomizing between multiple mechanisms may improve learning for arbitrary voter noise models. Finally, we use data from 5 large participatory budgeting elections that we organized across several US cities, along with other ranking data, to demonstrate the utility of our methods. In particular, we find that historically such elections have set K too low and that picking the right mechanism can be the difference between identifying the ultimate winner with only a 80% probability or a 99.9% probability after 400 voters.
The World Bank and social capital: Lessons from ten rural development projects in the Philippines and Mexico

Social capital is widely recognized as one of the few sources of capital available to the poor, yet the processes by which development policies affect the accumulation of that social capital are not well understood. The World Bank, through its funding of development projects, affects the institutional environments for the accumulation of such social capital. The question is how to determine whether that institutional context is enabling, and to what degree. This paper compares ten recent World Bank-funded rural development projects in Mexico and the Philippines to explore how the processes of project design and implementation influence the institutional environments for the accumulation of horizontal, vertical, and intersectoral forms of pro-poor social capital. The findings have conceptual and policy implications for understanding the political dynamics of creating enabling environments for social capital accumulation by the poor.
College Students' Reasons for Leaving Biomedical Fields: Disenchantment with Biomedicine or Attraction to Other Fields?

This study examined whether students who left biomedical fields of study during college did so primarily because they became disenchanted with those fields or because they felt attracted to alternative fields of study. We identified 1,193 students intending to pursue biomedical fields of study early in college, collected data about their beliefs and performance throughout college, and interviewed them near graduation about their future plans. Descriptively, we examined the topics students discussed as affecting their attrition decisions. Predictive research aims were to determine how academic performance, interest, and demographic factors predicted students’ likelihood of overall attrition and likelihood of reporting distinct reasons for attrition. Among the 192 students who left biomedical fields, 62.5% described leaving only in terms of feeling disenchanted, whereas 37.4% expressed that they left at least in part due to feeling attracted toward nonbiomedical fields. Most students who left biomedical fields expressed changing plans for reasons related to interest; this was especially prevalent among students who reported leaving due to attraction toward nonbiomedical fields. Predictive analyses showed that interest in biology and grades at the end of an introductory biology course predicted the likelihood of overall attrition and likelihood of leaving due to feeling disenchantment, whereas underrepresented ethnic minority status predicted these outcomes positively. Interest and course grades also predicted the likelihood of students leaving due to feeling attraction toward other fields, but interest was a stronger predictor relative to grades. Results highlight distinct types of attrition that may have implications for policies to promote STEM retention. (PsycInfo Database Record (c) 2021 APA, all rights reserved)
Aggregation of CAT Tails Blocks Their Degradation and Causes Proteotoxicity in S. Cerevisiae

The Ribosome-associated Quality Control (RQC) pathway co-translationally marks incomplete polypeptides from stalled translation with two signals that trigger their proteasome-mediated degradation. The E3 ligase Ltn1 adds ubiquitin and Rqc2 directs the large ribosomal subunit to append carboxy-terminal alanine and threonine residues (CAT tails). When excessive amounts of incomplete polypeptides evade Ltn1, CAT-tailed proteins accumulate and can self-associate into aggregates. CAT tail aggregation has been hypothesized to either protect cells by sequestering potentially toxic incomplete polypeptides or harm cells by disrupting protein homeostasis. To distinguish between these possibilities, we modulated CAT tail aggregation in Saccharomyces cerevisiae with genetic and chemical tools to analyze CAT tails in aggregated and un-aggregated states. We found that enhancing CAT tail aggregation induces proteotoxic stress and antagonizes degradation of CAT-tailed proteins, while inhibiting aggregation reverses these effects. Our findings suggest that CAT tail aggregation harms RQC-compromised cells and that preventing aggregation can mitigate this toxicity.
Chance-Constrained and Yield-Aware Optimization of Photonic ICs With Non-Gaussian Correlated Process Variations

Uncertainty quantification has become an efficient tool for uncertainty-aware prediction, but its power in yield-aware optimization has not been well explored from either theoretical or application perspectives. Yield optimization is a much more challenging task. On the one side, optimizing the generally nonconvex probability measure of performance metrics is difficult. On the other side, evaluating the probability measure in each optimization iteration requires massive simulation data, especially, when the process variations are non-Gaussian correlated. This article proposes a data-efficient framework for the yield-aware optimization of photonic ICs. This framework optimizes the design performance with a yield guarantee, and it consists of two modules: 1) a modeling module that builds stochastic surrogate models for design objectives and chance constraints with a few simulation samples and 2) a novel yield optimization module that handles probabilistic objectives and chance constraints in an efficient deterministic way. This deterministic treatment avoids repeatedly evaluating probability measures at each iteration, thus it only requires a few simulations in the whole optimization flow. We validate the accuracy and efficiency of the whole framework by a synthetic example and two photonic ICs. Our optimization method can achieve more than $30\times $ reduction of simulation cost and better design performance on the test cases compared with a Bayesian yield optimization approach developed recently.
Approximating nash social welfare under submodular valuations through (un)matchings

We study the problem of approximating maximum Nash social welfare (NSW) when allocating m indivisible items among n asymmetric agents with submodular valuations. The NSW is a well-established notion of fairness and efficiency, defined as the weighted geometric mean of agents' valuations. For special cases of the problem with symmetric agents and additive(-like) valuation functions, approximation algorithms have been designed using approaches customized for these specific settings, and they fail to extend to more general settings. Hence, no approximation algorithm with factor independent of m is known either for asymmetric agents with additive valuations or for symmetric agents beyond additive(-like) valuations. In this paper, we extend our understanding of the NSW problem to far more general settings. Our main contribution is two approximation algorithms for asymmetric agents with additive and submodular valuations respectively. Both algorithms are simple to understand and involve non-trivial modifications of a greedy repeated matchings approach. Allocations of high valued items are done separately by un-matching certain items and re-matching them, by processes that are different in both algorithms. We show that these approaches achieve approximation factors of O(n) and O(n log n) for additive and submodular case respectively, which is independent of the number of items. For additive valuations, our algorithm outputs an allocation that also achieves the fairness property of envy-free up to one item (EF1). Furthermore, we show that the NSW problem under submodular valuations is strictly harder than all currently known settings with an [MATH HERE] factor of the hardness of approximation, even for constantly many agents. For this case, we provide a different approximation algorithm that achieves a factor of [MATH HERE], hence resolving it completely.
Large deviations for functionals of some self-similar Gaussian processes

We prove large deviation principles for ∫0tγ(Xs)ds, where X is a d-dimensional self-similar Gaussian process and γ(x) takes the form of the Dirac delta function δ(x), |x|−β with β∈(0,d), or ∏i=1d|x...
Real-time Model-based Image Color Correction for Underwater Robots

Recently, a new underwater imaging formation model presented that the coefficients related to the direct and backscatter transmission signals are dependent on the type of water, camera specifications, water depth, and imaging range. This paper proposes an underwater color correction method that integrates this new model on an underwater robot, using information from a pressure depth sensor for water depth and a visual odometry system for estimating scene distance. Experiments were performed with and without a color chart over coral reefs and a shipwreck in the Caribbean. We demonstrate the performance of our proposed method by comparing it with other statistic-, physic-, and learning-based color correction methods. Applications for our proposed method include improved 3D reconstruction and more robust underwater robot navigation.
A derivative-free optimization algorithm for the efficient minimization of functions obtained via statistical averaging

This paper considers the efficient minimization of the infinite time average of a stationary ergodic process in the space of a handful of design parameters which affect it. Problems of this class, derived from physical or numerical experiments which are sometimes expensive to perform, are ubiquitous in engineering applications. In such problems, any given function evaluation, determined with finite sampling, is associated with a quantifiable amount of uncertainty, which may be reduced via additional sampling. The present paper proposes a new optimization algorithm to adjust the amount of sampling associated with each function evaluation, making function evaluations more accurate (and, thus, more expensive), as required, as convergence is approached. The work builds on our algorithm for Delaunay-based Derivative-free Optimization via Global Surrogates ($${\varDelta }$$-DOGS, see JOGO https://doi.org/10.1007/s10898-015-0384-2). The new algorithm, dubbed $$\alpha $$-DOGS, substantially reduces the overall cost of the optimization process for problems of this important class. Further, under certain well-defined conditions, rigorous proof of convergence to the global minimum of the problem considered is established.
Properties of M Dwarf Flares at Millimeter Wavelengths

We report on two millimeter flares detected by ALMA at 220 GHz from AU Mic, a nearby M dwarf. The larger flare had a duration of only $\sim35$ sec, with peak $L_{R}=2\times10^{15}$ erg s$^{-1}$ Hz$^{-1}$, and lower limit on linear polarization of $|Q/I|>0.12\pm0.04$. We examine the characteristics common to these new AU Mic events and those from Proxima Cen previously reported in MacGregor et al. (2018) - namely short durations, negative spectral indices, and significant linear polarization - to provide new diagnostics of conditions in outer stellar atmospheres and details of stellar flare particle acceleration. The event rates ($\sim20$ and $4$ events day$^{-1}$ for AU Mic and Proxima Cen, respectively) suggest that millimeter flares occur commonly but have been undetected until now. Analysis of the flare observing frequency and consideration of possible incoherent emission mechanisms confirms the presence of MeV electrons in the stellar atmosphere occurring as part of the flare process. The spectral indices point to a hard distribution of electrons. The short durations and lack of pronounced exponential decay in the light curve are consistent with formation in a simple magnetic loop, with radio emission predominating from directly precipitating electrons. We consider the possibility of both synchrotron and gyrosynchrotron emission mechanisms, although synchrotron is favored given the linear polarization signal. This would imply that the emission must be occurring in a low density environment of only modest magnetic field strength. A deeper understanding of this newly discovered and apparently common stellar flare mechanism awaits more observations with better-studied flare components at other wavelengths.
Low-damping ferromagnetic resonance in electron-beam patterned, high-Q vanadium tetracyanoethylene magnon cavities

The study of quantum coherent magnonic interactions relies on the ability to excite and exploit long lived spin wave excitations. That requirement has for many years placed yittrium iron garnet (YIG) as the leader in high-Q, low-loss magnetic resonance and coherent magnetic phenomena. High-quality YIG, however, is difficult to incorporate on-chip. The organic-based ferrimagnet vanadium tetracyanoethylene (V[TCNE]x) has recently emerged as an alternative to YIG due to its extremely low-loss (α = 3.98 × 10-5). Here we fill the low-loss on-chip material gap by presenting the semiconductor-compatible deposition, patterning, and characterization of V[TCNE]x thin films with lateral dimensions from microns to millimeters as well as a strong magnetic response to temperature and strain in V[TCNE]x. This work establishes the versatility of V[TCNE]x for on-chip applications requiring highly coherent magnetic excitations ranging from microwave communication to quantum information.
Performant {TCP} for Low-Power Wireless Networks

Low-power and lossy networks (LLNs) enable diverse applications integrating many resource-constrained embedded devices, often requiring interconnectivity with existing TCP/IP networks as part of the Internet of Things. But TCP has received little attention in LLNs due to concerns about its overhead and performance, leading to LLN-specific protocols that require specialized gateways for interoperability. We present a systematic study of a well-designed TCP stack in IEEE 802.15.4-based LLNs, based on the TCP protocol logic in FreeBSD. Through careful implementation and extensive experiments, we show that modern low-power sensor platforms are capable of running full-scale TCP and that TCP, counter to common belief, performs well despite the lossy nature of LLNs. By carefully studying the interaction between the transport and link layers, we identify subtle but important modifications to both, achieving TCP goodput within 25% of an upper bound (5-40x higher than prior results) and low-power operation commensurate to CoAP in a practical LLN application scenario. This suggests that a TCP-based transport layer, seamlessly interoperable with existing TCP/IP networks, is viable and performant in LLNs.
Interactions between DksA and Stress-Responsive Alternative Sigma Factors Control Inorganic Polyphosphate Accumulation in Escherichia coli.

ABSTRACT Bacteria synthesize inorganic polyphosphate (polyP) in response to a variety of different stress conditions. polyP protects bacteria by acting as a protein-stabilizing chaperone, metal chelator, or regulator of protein function, among other mechanisms. However, little is known about how stress signals are transmitted in the cell to lead to increased polyP accumulation. Previous work in the model enterobacterium Escherichia coli has indicated that the RNA polymerase-binding regulatory protein DksA is required for polyP synthesis in response to nutrient limitation stress. In this work, I set out to characterize the role of DksA in polyP regulation in more detail. I found that overexpression of DksA increases cellular polyP content (explaining the long-mysterious phenotype of dksA overexpression rescuing growth of a dnaK mutant at high temperatures) and characterized the roles of known functional residues of DksA in this process, finding that binding to RNA polymerase is required but that none of the other functions of DksA appear to be necessary. Transcriptomics revealed genome-wide transcriptional changes upon nutrient limitation, many of which were affected by DksA, and follow-up experiments identified complex interactions between DksA and the stress-sensing alternative sigma factors FliA, RpoN, and RpoE that impact polyP production, indicating that regulation of polyP synthesis is deeply entwined in the multifactorial stress response network of E. coli. IMPORTANCE Inorganic polyphosphate (polyP) is an evolutionarily ancient, widely conserved biopolymer required for stress resistance and pathogenesis in diverse bacteria, but we do not understand how its synthesis is regulated. In this work, I gained new insights into this process by characterizing the role of the transcriptional regulator DksA in polyP regulation in Escherichia coli and identifying previously unknown links between polyP synthesis and the stress-responsive alternative sigma factors FliA, RpoN, and RpoE.
An Architecture for Inter-Domain Troubleshooting

In this paper, we explore the constraints of a new problem: that of coordinating network troubleshooting among peer administrative domains and untrusted observers. Our approach permits any entity to report problems, whether it is a Network Operations Center (NOC), end-user, or application. Our goals are to define the inter-domain coordination problem clearly, and to develop an architecture which allows observers to report problems and receive timely feedback, regardless of their own locations and identities. By automating this process, we also relieve human bottlenecks at help desks and NOCs whenever possible. We present a troubleshooting approach for coordinating problem diagnosis, and describe Global Distributed Troubleshooting (GDT), a distributed protocol which realizes this approach. We show through simulation that GDT scales well as the number of observers and problems grows.
Influence of atmospheric rivers on the Leeuwin Current system

Previous work has demonstrated the strong ocean response to atmospheric rivers (ARs) in the northeast Pacific including coastal currents along the west coast of North America, because of strong surface winds associated with ARs. A recent study on the global distribution of ARs also suggests that the southeast Indian Ocean is one of the areas of relatively strong AR activity. This study investigates the influence of ARs on the Leeuwin Current system, which is one of the major boundary currents in the Indian Ocean. It is demonstrated that winds associated with typical ARs in the southeast Indian Ocean can generate strong poleward coastal currents and sea level rise along the west coast of Australia using a high-resolution ocean reanalysis (0.08° HYCOM). The composite of upper ocean currents and sea surface height (SSH) associated with landfalling ARs along the west coast of Australia is constructed using the HYCOM reanalysis, long-term AR data set, and tide gauge data. The enhancement of the poleward currents generated by ARs is found in the composite, and the magnitude of the enhancement is comparable to the strength of the Leeuwin Current itself. The results also indicate that the fluctuation of SSH and coastal currents along the west coast propagates along the southern coast all the way to the southeast coast (Pacific side) of Australia. The SSH propagation along the coasts is also detected in the tide gauge data in the west and southern coasts of Australia.
The upper bound theorem for flag homology 5-manifolds

Abstract We prove that among all flag homology 5-manifolds with n vertices, the join of 3 circles of as equal length as possible is the unique maximizer of all the face numbers. The same upper bounds on the face numbers hold for 5-dimensional flag Eulerian normal pseudomanifolds.
Chapter 6 – Secondary Storage

Publisher Summary Compared to secondary storage, main storage is faster, but smaller and costlier. The two important forms of secondary storage are tape and disk. Data is stored on tape and disk as tiny magnetized spots. The information is read or written as the tape or disk passes by a read/ write head. Each spot represents one bit. On nine-track tape, eight bits designate the character and one bit is a parity bit for error detection. The data transfer rate is the number of characters per second that might be transferred between main storage and a secondary storage device. With sequential access, records are written or retrieved in order one after the other. Interblock gaps are the portions of blank tape that pass over the read/write head as the tape drive speeds up or slows down. Tape is useful in batch processing applications in which large amounts of data are processed. It is also popular for backing up information recorded on disks for security purposes. Disks are flat platters that look like phonograph records. They are coated with a magnetizable material. Information is recorded on the surface of a disk platter in circular tracks.
The Role of Discretion in the Criminal Justice System

with "qualifying" criminal histories. We find that an increase in the statutory sentence for a given crime can increase sentence length for those who are charged with the crime, and also for those who are charged with factually "similar" crimes, where a "similar" crime is defined as one that has legal elements in common with the given crime. These spillovers are consistent with neither broad social norms nor internal social norms, so we conclude that discretion takes a less-well studied form, which we call "prosecutorial maximization."
Should Central Banks Raise their Inflation Targets? Some Relevant Issues

Should central banks, because of the zero-lower-bound problem, raise their inflation-rate targets? Several arguments are relevant. (1) In the absence of the ZLB, the optimal steady-state inflation rate, according to standard New Keynesian reasoning, lies between the Friedman-rule value of deflation at the steady-state real interest rate and the Calvo-model value of zero, with calibration indicating a larger weight on the latter. (2) An attractive modification of the Calvo pricing equation would, however, imply that the weight on the second of these values should be zero. (3) There may be some scope for activist monetary policy to be effective even when the one-period interest rate is at the ZLB; but there is professional disagreement on this matter. (4) Present institutional arrangements are not immutable. In particular, elimination of traditional currency is feasible (even arguably attractive) and would remove the ZLB constraint on policy. (5) Increasing target inflation for the purpose of avoiding occasional ZLB difficulties would tend to undermine the rationale for central bank independence and would constitute an additional movement away from policy recognition of the economic necessity for intertemporal discipline.
Experimental observation of the influence of furnace temperature profile on convection and segregation in the vertical Bridgman crystal growth technique

Abstract Azulene-doped naphthalene was directionally solidified during the vertical Bridgman-Stockbarger technique. Doping homogeneity and convection were determined as a function of the temperature profile in the furnace and the freezing rate. Convection velocities were two orders of magnitude lower when the temperature increased with height. Rarely was the convection pattern axisymmetric, even though the temperature varied less than 0.1 K around the circumference of the growth ampoule. Correspondingly the cross sectional variation in azulene concentration tended to by asymmetric, especially when the temperature increased with height. This cross sectional variation changed dramatically along the ingot, reflecting changes in convection presumably due to the decreasing height of the melt. Although there was large scatter and irreproducibility in the cross sectional variation in doping, this variation tended to be least when the growth rate was low and the convection was vigorous. It is expected that compositional variations would also be small at high growth rates with weak convection and flat interfaces, although this was not investigated in the present experiments. Neither rotation of the ampoule nor deliberate introduction of thermal asymmetries during solidification had a significant influence on cross sectional variations in doping. It is predicted that slow directional solidification under microgravity conditions could produce greater inhomogeneities than on Earth. Combined use of microgravity and magnetic fields would be required to achieve homogeneity when it is necessary to freeze slowly in order to avoid constitutional supercooling.
The impact of the Civil War on capital intensity and labor productivity in southern manufacturing

Abstract After the Civil War wages fell in the South relative to the non-South, but interest rates and other measures of the costs of capital increased. Using archival data for manufacturing establishments, we show that capital–output and capital–labor ratios in southern manufacturing declined relative to non-southern manufacturing after the War, precisely in the direction implied by the regional shifts in factor prices. Labor productivity in southern manufacturing also declined, and a significant portion of this decline can be attributed to the reduction in capital intensity.
A Biophysical Model of Supercoiling Dependent Transcription Predicts a Structural Aspect to Gene Regulation

Background Transcription in Escherichia coli generates positive supercoiling in the DNA, which is relieved by the enzymatic activity of gyrase. Recently published experimental evidence suggests that transcription initiation and elongation are inhibited by the buildup of positive supercoiling. It has therefore been proposed that intermittent binding of gyrase plays a role in transcriptional bursting. Considering that transcription is one of the most fundamental cellular processes, it is desirable to be able to account for the buildup and release of positive supercoiling in models of transcription.
The Effect of Public Insurance Coverage for Childless Adults on Labor Supply

This study provides plausibly causal estimates of the effect of public insurance coverage on the employment of non-elderly, non-disabled adults without dependent children (“childless adults”). We use both a regression discontinuity design and propensity score matching differences in differences to take advantage of the sudden imposition of an enrollment cap to compare the labor supply of enrollees to eligible applicants placed on a waitlist. We find enrollment into public insurance leads to sizable and statistically meaningful reductions in employment up to at least 9 quarters later, though the estimated size of this reduction varies from 2 to 10 percentage points depending upon the model used. In light of these results, policymakers should be prepared for a reduction in labor supply among childless adults affected by the Medicaid expansion under the Affordable Care Act.
2.08 The Aldol Reaction: Group I and Group II Enolates

Traditionally, aldol reactions were carried out under protic conditions, such that the enolate was formed reversibly. An added measure of control is possible if one uses a sufficiently strong base that the enolate may be quantitatively formed prior to addition of the electrophile. The renaissance that has occurred in the aldol reaction in the last three decades has been mainly due to the development of methods for the formation and use of preformed enolates. The simplest enolates to prepare are those associated with lithium, boron and magnesium, and there now exists a considerable literature documenting certain aspects of lithium, boron and magnesiumenolate aldol chemistry. This chapter summarizes the aldol chemistry of preformed enolates of these Group I and Group II metals. Other chapters in this volume deal with boron enolates, zinc enolates, transition metal enolates and the related chemistry of silyl and stannyl enol ethers.
6 – Process costing

Publisher Summary This chapter discusses process costing. Process costing introduces the student to the costing of amorphous substances, such as chemicals, petroleum products, and certain foodstuffs. The essential problem with process costing is the valuation of working in process. The difficulty arises with computing the volumes in stock to produce an acceptable valuation of both finished goods and work-in-progress. A normal loss is computed on the basis of past results and is often expressed as a percentage of the input to the process. It has the effect of increasing the unit cost of the good production. Abnormal losses are credited out of the process account into an abnormal loss account at the full unit cost value. The information generated by the process cost accounts can be fundamental to the decision making process.
Catecholamine metabolism and affective disorders: Studies of MHPG excretion

Publisher Summary This chapter elaborates the catecholamine metabolism and affective disorders. The changes in 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion which were associated with changes in affective state are examined. The findings from longitudinal studies of individual patients with naturally occurring or amphetamine induced manic-depressive episodes indicate that levels of urinary MHPG are relatively lower during depressions and higher during manic or hypomanic episodes than after clinical remissions, and these findings have been confirmed by other investigators but not by all. The relationship between MHPG excretion and clinical state that has been observed in manic-depressive patients, is illustrated, which summarizes the changes in MHPG excretion in a manic-depressive patient studied longitudinally through five successive periods which were defined by differences in clinical state. All depressed patients do not excrete comparably low levels of MHPG, and preliminary findings have suggested that MHPG excretion may provide a biological criterion for classifying the depressive disorders, and for predicting the responses to specific forms of antidepressant pharmacotherapy.
The Role of Corporate Political Connections in Commercial Lawsuits: Evidence From Chinese Courts:

Like courts in democratic regimes, courts under authoritarianism play an important role in the regulation of complex economies. In particular, scholars suggest that authoritarian judiciaries are co...
Lévy Processes in Asset Pricing

After mentioning empirical motivation of Levy processes in asset pricing, an overview of properties related to Levy processes is given. Certain difficulties in applying Levy processes, such as the volatility clustering effect and those in distinguishing the tail behavior of asset returns, are also discussed. Keywords: leptokurtic distribution; jump diffusion; subordinator; infinite activity Levy processes; volatility clustering effect; tail distribution
A defender‐attacker optimization of Port Radar surveillance

The U.S. Coast Guard, Customs and Border Patrol, Marine Corps, and Navy have deployed several hundred port patrol vessels to protect waterways, U.S. Navy ships and other high-value assets in ports world-wide. Each vessel has an armed crew of four, is relatively fast, and features a surface search radar, radios, and a machine gun. These vessels coordinate surveillance patrols in groups of two or four. We developed a mathematical model for advantageously positioning these vessels, and possibly shore-based radar too, to minimize the probability that an intelligent adversary in one or more speedboats will evade detection while mounting an attack. Attackers can use elevated obstructions to evade radar detection in their attack paths, and ports feature many such restrictions to navigation and observation. A key, but realistic assumption complicates planning: the attackers will be aware of defensive positions and capabilities in advance of mounting their attack. The defender-attacker optimization suggests plans here for a fictitious port, the port of Hong Kong, and the U.S. Navy Fifth Fleet Headquarters in Bahrain. In these cases, the defender can almost certainly detect any attack, even though the attacker, observing defender prepositioning, plans clever, and evasive attack tracks. Published 2011 Wiley Periodicals, Inc.† Naval Research Logistics, 2011
A Geometric Characterization of Population Coding in the Prefrontal Cortex and Hippocampus during a Paired-Associate Learning Task

Large-scale neuronal recording techniques have enabled discoveries of population-level mechanisms for neural computation. However, it is not clear how these mechanisms form by trial-and-error learning. In this article, we present an initial effort to characterize the population activity in monkey prefrontal cortex (PFC) and hippocampus (HPC) during the learning phase of a paired-associate task. To analyze the population data, we introduce the normalized distance, a dimensionless metric that describes the encoding of cognitive variables from the geometrical relationship among neural trajectories in state space. It is found that PFC exhibits a more sustained encoding of the visual stimuli, whereas HPC only transiently encodes the identity of the associate stimuli. Surprisingly, after learning, the neural activity is not reorganized to reflect the task structure, raising the possibility that learning is accompanied by some "silent" mechanism that does not explicitly change the neural representations. We did find partial evidence on the learning-dependent changes for some of the task variables. This study shows the feasibility of using normalized distance as a metric to characterize and compare population-level encoding of task variables and suggests further directions to explore learning-dependent changes in the neural circuits.
Natural History: the sense of wonder, creativity and progress in ecology

This essay addresses the question of blending natural history and ecological wisdom into the genuine creativity exemplified by Prof. Ramon Margalef. Many have observed that modern biology is a triumph of precision over accuracy, and that ecology has sought maturity by striving toward this model in which the precision value of the tools has supplanted important questions. In pursuing a model of hard science, ecology has struggled with Popperian approaches designed to create a thin patina of real science over the vast seas of uncertainty so admired by the naturalists. We start with a discussion of the importance of natural history in ecology and conservation, and the present state of natural history in academic ecology. We then discuss the respect for natural history in human cultures, and conclude that an infatuation with authority has obfuscated the important truths to be found in nature. We consider some general processes associated with creativity, and finally we ask how natural history influences creativity in ecology. We conclude that the soaring creativity exemplified by Ramon Margalef is based on a joyful almost spiritual understanding of natural history and the courage to avoid authority.
Chapter 17 – Heber Binary Plants, Imperial Valley, California, USA

Heber, a town in Imperial Valley, California, is home to two geothermal power stations. Heber was first explored as an oil and gas prospect, but two wells drilled in 1972 confirmed the existence of a liquid-dominated, moderate-temperature, low-salinity reservoir. The chapter discusses the development of the first Heber binary plant, the Heber Binary Demonstration plant. The plant had its share of problems, including that the parasitic power requirements were not proportional to the load. The needed production wells were not completed on schedule and the plant was decommissioned and eventually dismantled. The second attempt to develop the Heber resource began in 1992 and has achieved the success that was hoped for but not realized when the original Heber demonstration plant was built. Optimization of the power complex has continued to the present.
Production of Volatiles from Fatty Acids and Oils by Irradiation

To understand the mechanisms of off-odor production in irradiated meat, the volatile compounds produced from individual fatty acids by irradiation were identified. Nonirradiated oil emulsions prepared with polyunsaturated fatty acids (PUFAs) produced many volatile compounds, but the amounts of volatiles generally decreased after irradiation. Although volatile profiles of fatty acid emulsions were changed by irradiation, the odor characteristics and intensity between irradiated and nonirradiated fatty acid emulsions were not different. Thiobarbituric acid-reactive substances (TBARS) values indicated that irradiation accelerated lipid oxidation during subsequent storage, but the volatiles produced by lipid oxidation were not the major contributors of off-odor in irradiated samples.
A Method for Calculating Export Supply and Import Demand Elasticities

Frequently in applied work, researchers need to utilize values for price elasticities of import demand and export supply. Unfortunately, econometric estimates of these elasticities are limited, perhaps due to the difficulties inherent in estimating them. This paper uses a methodology for estimating price elasticities of import demand and export supply for 87 countries without using econometrics directly.
Rademacher's conjecture and expansions at roots of unity of products generating restricted partitions

Abstract The generating function for restricted partitions is a finite product with a Laurent expansion at each root of unity. The question of the behavior of these Laurent coefficients as the size of the product increases goes back to Rademacher and his work on partitions. Building on the methods of Drmota, Gerhold and previous results of the author, we complete this description and give the full asymptotic expansion of each coefficient at every root of unity. These techniques are also shown to give the asymptotics of Sylvester waves.
Contextualizing covid-19 spread: a county level analysis, urban versus rural, and implications for preparing for the next wave

Background : Contextual determinants of health including social, environmental, healthcare and others, are a so-called deck of cards one is dealt. The ability to modify health outcomes varies then based upon how one’s hand is played. It is thus of great interest to understand how these determinants associate with the emerging pandemic coronavirus disease 2019 (COVID-19). Methods : To this end, we conducted a deep-dive analysis into this problem using a recently curated public dataset on COVID-19 that connects infection spread over time to a rich collection of contextual determinants for all counties of the U.S and Washington, D.C. Results : Using random forest machine learning methodology, we identified a relevant constellation of contextual factors of disease spread which manifest differently for urban and rural counties. Conclusions : The findings also have clear implications for better preparing for the next wave of disease.
Genetic architecture underlying changes in carotenoid accumulation during the evolution of the blind Mexican cavefish, Astyanax mexicanus.

Carotenoids are lipid-soluble yellow to orange pigments produced by plants, bacteria, and fungi. They are consumed by animals and metabolized to produce molecules essential for gene regulation, vision, and pigmentation. Cave animals represent an interesting opportunity to understand how carotenoid utilization evolves. Caves are devoid of light, eliminating primary production of energy through photosynthesis and, therefore, limiting carotenoid availability. Moreover, the selective pressures that favor carotenoid-based traits, like pigmentation and vision, are relaxed. Astyanax mexicanus is a species of fish with multiple river-adapted (surface) and cave-adapted populations (i.e., Tinaja, Pachon, Molino). Cavefish exhibit regressive features, such as loss of eyes and melanin pigment, and constructive traits, like increased sensory neuromasts and starvation resistance. Here, we show that, unlike surface fish, Tinaja and Pachon cavefish accumulate carotenoids in the visceral adipose tissue. Carotenoid accumulation is not observed in Molino cavefish, indicating that it is not an obligatory consequence of eye loss. We used quantitative trait loci mapping and RNA sequencing to investigate genetic changes associated with carotenoid accumulation. Our findings suggest that multiple stages of carotenoid processing may be altered in cavefish, including absorption and transport of lipids, cleavage of carotenoids into unpigmented molecules, and differential development of intestinal cell types involved in carotenoid assimilation. Our study establishes A. mexicanus as a model to study the genetic basis of natural variation in carotenoid accumulation and how it impacts physiology.