cssi/SciSciGPT-SciSciNet huggingface dataset:
Primaquine plus artemisinin combination therapy for reduction of malaria transmission: promise and risk

Reduction of gametocyte transmission from humans to mosquitoes is a key component of malaria elimination. The study by Goncalves and colleagues provides valuable new data on how the addition of low-dose primaquine to artemether-lumefantrine affects reduction of gametocytemia and transmission of gametocytes to mosquitoes in asymptomatically Plasmodium falciparum-infected children without G6PD deficiency, and on the degree to which low-dose primaquine affects hemoglobin levels in these children. The study sets the stage for future research required for consideration of an artemisinin combination therapy (ACT)-primaquine regimen in mass drug administration campaigns. Future studies will need to evaluate toxicity in adults and G6PD deficient persons, assess gametocyte transmission from adults, evaluate different ACT drugs with primaquine, and assess the implications of “rare” toxicities in large treatment populations, such as hemolysis requiring blood transfusion. The study highlights both the promise and the potential risk of ACT-primaquine treatment in malaria elimination campaigns.
Ultracompressible, High-Rate Supercapacitors from Graphene-Coated Carbon Nanotube Aerogels

Emerging applications for electrochemical energy storage require devices that not only possess high power and energy, but also are capable of withstanding mechanical deformation without degradation of performance. To this end, we have constructed electric double layer capacitors (EDLCs), also referred to as supercapacitors, using thick, ultracompressible graphene-coated carbon nanotube aerogels as electrodes. These electrodes showed a high capacitance in both aqueous and room-temperature ionic liquid (RTIL) electrolytes, achieving between 60 and100 F/g, respectively, with the performance stable over hundreds of charge/discharge cycles and at high rates exceeding 1 V/s. This performance was retained fully under 90% compression of the systems, allowing us to construct cells with high volumetric capacitances of ∼5–18 F/cm3 in aqueous and RTIL electrolytes, respectively, which are 50–100 times higher than comparable compressible EDLCs (∼0.1 F/cm3). Further, the volumetric capacitances approach values reported...
Optimal $k$ -Leader Selection for Coherence and Convergence Rate in One-Dimensional Networks

We study the problem of optimal leader selection in consensus networks under two performance measures: 1) formation coherence when subject to additive perturbations, as quantified by the steady-state variance of the deviation from the desired trajectory, and 2) convergence rate to a consensus value. The objective is to identify the set of $k$ leaders that optimizes the chosen performance measure. In both cases, an optimal leader set can be found by an exhaustive search over all possible leader sets; however, this approach is not scalable to large networks. In recent years, several works have proposed approximation algorithms to the $k$ -leader selection problem, yet the question of whether there exists an efficient, noncombinatorial method to identify the optimal leader set remains open. This work takes a first step toward answering this question. We show that, in 1-D weighted graphs, namely, path graphs and ring graphs, the $k$ -leader selection problem can be solved in polynomial time (in $k$ and the network size $n$ ). We give an $O(n^{3})$ solution for optimal $k$ -leader selection in path graphs and an $O(kn^{3})$ solution for optimal $k$ -leader selection in ring graphs.
COMPUTATIONAL ASSESSMENT OF GLENOID MORPHOLOGY IN US AND AUSTRALIAN PATIENTS

Background Malposition of the glenoid component in total shoulder arthroplasty (TSA) is associated with higher strain patterns and can result in component loosening. Glenoid hardware placement and optimal size remain challenging due to the difficult joint exposure and visualization of anatomical reference landmarks during the procedure. Therefore, understanding both normal and variant patterns of glenoid anatomy is imperative for success in TSA. To better understand individual variations in glenoid morphology, this study aimed to compare the glenoid anatomy in a cohort of male and female patients from the United States (US) and Australia (AUS). Methods Computed tomography (CT) data were analyzed from 41 male and 35 female shoulders; 39 of which were from a US population and 37 from an AUS population. These data were used to create statistical shape models (SSM) representing the average and ±1 standard deviations of the first mode of variation of each group (Materialise, Leuven, Belgium). All measurements were performed with 3-matic computer assisted design software (Materialise, Leuven, Belgium). On each model, glenoid height was measured as the distance from the most superior to the most inferior point on the glenoid face. Glenoid width was measured as the distance from the most anterior to the most posterior point on the glenoid face. Surface area was measured as the concave surface of the glenoid face (Figure 1). Glenoid vault depth was measured in the midsection of the glenoid face. Results The overall glenoid dimensions were similar between AUS and US populations with average SSMs having widths of 24.68 and 25.72mm, heights of 34.63 mm and 34.85 mm, vault depths of 31.81 mm and 30.20 mm, and surface areas of 665.8 mm2 and 659.2 mm2 (Figure 2). All measurements were also similar for sex matched SSMs (Figure 3). We did observe differences between males and females within these populations, with males in general having larger glenoids in all parameters measured but the greatest difference was seen in surface area. Discussion Our findings indicate that glenoid morphology is similar between these populations. This supports the external validity of previous studies of glenoid anatomy in these populations, and the use of similar implants between these groups. The gender differences observed in this study reflect previously reported differences. Interestingly, the glenoid depths were greater than the length of most commercial glenoid pegs (14–20 mm) or RSA screws (15–30 mm), indicating that implant perforation of the glenoid vault is unlikely if surgeons properly place and select appropriate sized glenoid implants in either population.
Solving the wrong hierarchy problem

Many theories require augmenting the Standard Model with additional scalar fields with large order one couplings. We present a new solution to the hierarchy problem for these scalar fields. We explore parity- and $$ {\mathbb{Z}}_2 $$ -symmetric theories where the Standard Model Higgs potential has two vacua. The parity or $$ {\mathbb{Z}}_2 $$ copy of the Higgs lives in the minimum far from the origin while our Higgs occupies the minimum near the origin of the potential. This approach results in a theory with multiple light scalar fields but with only a single hierarchy problem, since the bare mass is tied to the Higgs mass by a discrete symmetry. The new scalar does not have a new hierarchy problem associated with it because its expectation value and mass are generated by dimensional transmutation of the scalar quartic coupling. The location of the second Higgs minimum is not a free parameter, but is rather a function of the matter content of the theory. As a result, these theories are extremely predictive. We develop this idea in the context of a solution to the strong CP problem. We show this mechanism postdicts the top Yukawa to be within 1σ of the currently measured value and predicts scalar color octets with masses in the range 9-200 TeV.
Microstrip Antenna Arrays for Implantable and Wearable Wireless Applications

Flexible microstrip antenna arrays have become a necessity in today’s miniaturized biomedical wireless devices. Implantable and wearable biomedical devices such as pacemakers, drug delivery systems, heart rate monitors, and respiratory monitors need to communicate with exterior base station devices and relayed to healthcare professionals. In this paper, multiple flexible microstrip antenna arrays are designed and simulated for these applications. The frequency bands of 5.2 GHz and 5.8 GHz are utilized to provide a high bandwidth communication link. CST Microwave Studio was used for the modeling and simulation of the antennas. The reflection coefficient, gain, and correlation coefficient for each antenna are presented and discussed. The presented antennas can be utilized together as an array for enhanced gain or independently in a Multiple Input Multiple Output (MIMO) system.
Enhancing Traffic Analysis Resistance for Tor Hidden Services with Multipath Routing

Hidden service is a very important feature of Tor, which supports server operators to provide a variety of Internet services without revealing their locations. A large number of users rely on Tor hidden services to protect their anonymity. Around 30,000 servers are running hidden services every day. However, hidden services are particularly vulnerable to traffic analysis attacks especially when an entry guard of a hidden server is compromised by an adversary. In this paper, we propose a multipath routing scheme for Tor hidden servers (mTorHS) to defend against traffic analysis attacks. By transferring data through multiple circuits between hidden server and a special server rendezvous point, mTorHS is able to exploit flow splitting and flow merging to eliminate inter-cell correlations of the original flow. Experiments on the Shadow simulator [1] show that our scheme can effectively mitigate the risk of traffic analysis even when the most robust watermarking technique is applied.
Insider sales in IPOs: Consequences of liquidity needs

Abstract We examine the causes and consequences of insiders' liquidity needs as a motivation for the secondary sales in an initial public offering (IPO). Four main findings resulted from our analysis: (1) lower levels of pre-IPO cash holdings lead to lower levels of executive compensation, (2) smaller cash-pay results in greater levels of insider sales, (3) equity-pay levels do not directly affect the insider sales but do influence the presence of an IPO lockup period, which in turn affects the levels of insider sales, and (4) higher levels of insider sales due to liquidity needs result in lower levels of underpricing and long-run returns. Taken together these results also suggest that liquidity induced secondary sales can be a source of agency problems.
Asymmetric Synthesis of syn- and anti-1,3-Amino Alcohols

The first application of metalloenamines derived from N-sulfinyl imines is reported for the highly diastereoselective addition to aldehydes. Reduction of the β-hydroxy-N-sulfinyl imine products with catecholborane and LiBHEt3 provides syn- and anti-1,3-amino alcohol derivatives, respectively, with very high diastereomeric ratios.
Precision targeting for multiple swingby interplanetary trajectories

A rapid technique for precision targeting of multiple swingby interplanetary trajectories is described. The general multiple swingby interplanetary trajectory is modeled as a sequence of alternating heliocentric and planetocentric trajectory segments constrained to match in position and time at each planetary sphere of influence penetration. An iterative procedure is employed to vary these penetration points to match the segments in velocity as well. Effects of ]V-body disturbing accelerations on the trajectory segments are included using a general perturbation technique. Results which indicate a rapid rate of convergence and a high level of accuracy along the entire trajectory without the need for numerical integration are presented for missions with two and three swingbys.
Conformal symmetry and its breaking in two dimensional Nearly Anti-de-Sitter space

We study a two dimensional dilaton gravity system, recently examined by Almheiri and Polchinski, which describes near extremal black holes, or more generally, nearly $AdS_2$ spacetimes. The asymptotic symmetries of $AdS_2$ are all the time reparametrizations of the boundary. These symmetries are spontaneously broken by the $AdS_2$ geometry and they are explicitly broken by the small deformation away from $AdS_2$. This pattern of spontaneous plus explicit symmetry breaking governs the gravitational backreaction of the system. It determines several gravitational properties such as the linear in temperature dependence of the near extremal entropy as well as the gravitational corrections to correlation functions. These corrections include the ones determining the growth of out of time order correlators that is indicative of chaos. These gravitational aspects can be described in terms of a Schwarzian derivative effective action for a reparametrization.
Ovarian cancer. Advances in management.

Substantial progress has been made in understanding the biologic behavior of ovarian cancer and in assessing disease states and response to therapy by transvaginal sonography, CT scan, and tumor markers such as CA-125. There is no longer controversy regarding the importance of adequate surgical staging, the need for cytoreduction, and the utility of cisplatin- or carboplatinbased combination chemotherapy. Increasing the chemotherapy dose through escalated systemic doses or intraperitoneal administration, revising multidrug resistance, using biologic response modifiers, and developing new methods of chemosensitivity testing may help improve the 5-year survival rate for stage III ovarian cancer, which now is less than 30%.
Copper-Catalyzed Synthesis of Trifluoroethylarenes from Benzylic Bromodifluoroacetates

Trifluoroethylarenes are found in a variety of biologically active molecules, and strategies for accessing this substructure are important for developing therapeutic candidates and biological probes. Trifluoroethylarenes can be directly accessed via nucleophilic trifluoromethylation of benzylic electrophiles; however, current catalytic methods do not effectively transform electron-deficient substrates and heterocycles. To address this gap, we report a Cu-catalyzed decarboxylative trifluoromethylation of benzylic bromodifluoroacetates. To account for the tolerance of sensitive functional groups, we propose an inner-sphere mechanism of decarboxylation.
Copper(I)-Catalyzed Oxidation of Alkenes Using Molecular Oxygen and Hydroxylamines: Synthesis and Reactivity of α-Oxygenated Ketones

The copper(I)-catalyzed oxidation of alkenes with molecular oxygen and N-hydroxyphthalimide (NHPI) or N-hydroxybenzotriazole (HOBt) provided α-oxygenated ketones. The reaction proceeded under a balloon of O2 at room temperature to furnish the dioxygenated products in 50-90% yield. These compounds, particularly the HOBt derivatives, can be further functionalized with phosphorus, nitrogen, and sulfur nucleophiles to give synthetically useful products.
Active Ge Based Devices for Silicon Photonics

Some of the crucial building blocks for Si photonics are high performance photodetectors, modulators, and efficient light sources. High quality Ge epitaxial films on Si have opened new possibilities for high performance CMOS compatible devices.
Ideological Fit Enhances Interpersonal Orientations

Living among politically dissimilar others leads individuals to feel left out and ultimately predicts mobility away from an area. However, does living in politically incongruent environment affect how we relate to other people? In two national samples (n = 12,846 and n = 6,316), the congruence between an individual’s ideological orientation and their community’s ideological orientation were examined. Lack of ideological fit with one’s environment was associated with a difficulty to form close relationships and lower perspective taking. Our findings illustrate the psychological effects of living among dissimilar others and possible explanations for how social environments modulate interpersonal relations.
Olfactory perception of chemically diverse molecules

Understanding the relationship between a stimulus and how it is perceived reveals fundamental principles about the mechanisms of sensory perception. While this stimulus-percept problem is mostly understood for color vision and tone perception, it is not currently possible to predict how a given molecule smells. While there has been some progress in predicting the pleasantness and intensity of an odorant, perceptual data for a larger number of diverse molecules are needed to improve current predictions. Towards this goal, we tested the olfactory perception of 480 structurally and perceptually diverse molecules at two concentrations using a panel of 55 healthy human subjects. For each stimulus, we collected data on perceived intensity, pleasantness, and familiarity. In addition, subjects were asked to apply 20 semantic odor quality descriptors to these stimuli, and were offered the option to describe the smell in their own words. Using this dataset, we replicated several previous correlations between molecular features of the stimulus and olfactory perception. The number of sulfur atoms in a molecule was correlated with the odor quality descriptors “garlic,” “fish,” and “decayed,” and large and structurally complex molecules were perceived to be more pleasant. We discovered a number of correlations in intensity perception between molecules. We show that familiarity had a strong effect on the ability of subjects to describe a smell. Many subjects used commercial products to describe familiar odorants, highlighting the role of prior experience in verbal reports of olfactory perception. Nonspecific descriptors like “chemical” were applied frequently to unfamiliar odorants, and unfamiliar odorants were generally rated as neither pleasant nor unpleasant. We present a very large psychophysical dataset and use this to correlate molecular features of a stimulus to olfactory percept. Our work reveals robust correlations between molecular features and perceptual qualities, and highlights the dominant role of familiarity and experience in assigning verbal descriptors to odorants.
Current gain above 10 in sub-10 nm base III-nitride tunneling hot electron transistors with GaN/AlN emitter

We report on demonstration of GaN tunneling hot electron transistors (THETA) with dc current gain up to 14.5 in common-emitter configuration, which is highest value reported to date in GaN-based hot electron transistors. THETA is a promising candidate to obtain vertical high frequency transistors in GaN. In a THETA, an emitter-base (EB) barrier is applied to tunnel-inject hot electron beams, and a base-collector (BC) barrier filter cold electrons leak from the base [1]. Under forward operation condition emitter-base bias V EB C ). The electrons relaxed within the base due to scatterings and quantum reflections contribute to the base current (I B ). When the EB junction is sufficiently biased, I C exceeds IB, resulting in a current gain. In this work, the transistors were designed to have unintentionally doped (UID) GaN/AlN emitter barrier to block low energy electrons, ultra-thin base (<10 nm) to enhance ballistic transport, and polarization-engineered BC barrier to limit leakage.
IL-4 impairs wound healing potential in the skin by repressing fibronectin expression.

Background Atopic dermatitis (AD) is characterized by intense pruritis and is a common childhood inflammatory disease. Many factors are known to affect AD development, including the pleiotropic cytokine IL-4. Yet little is known regarding the direct effects of IL-4 on keratinocyte function. Objective and Methods In this report RNA sequencing and functional assays were used to define the effect of the allergic environment on primary keratinocyte function and wound repair in mice. Results Acute or chronic stimulation by IL-4 modified expression of more than 1000 genes expressed in human keratinocytes that are involved in a broad spectrum of nonoverlapping functions. Among the IL-4–induced changes, repression of fibronectin critically impaired the human keratinocyte wound response. Moreover, in mouse models of spontaneous and induced AD-like lesions, there was delayed re-epithelialization. Importantly, topical treatment with fibronectin restored the epidermal repair response. Conclusion Keratinocyte gene expression is critically shaped by IL-4, altering cell fate decisions, which are likely important for the clinical manifestations and pathology of allergic skin disease.
The influence of cardiorespiratory fitness on the decrement in maximal aerobic power at high altitude.

There are conflicting reports in the literature which imply that the decrement in maximal aerobic power experienced by a sea-level (SL) resident sojourning at high altitude (HA) is either smaller or larger for the more aerobically “fit” person. In the present study, data collected during several investigations conducted at an altitude of 4300 m were analyzed to determine if the level of aerobic fitness influenced the decrement in maximal oxygen uptake \(\dot V_{O_{2\max } } \) at HA. The \(\dot V_{O_{2\max } } \) of 51 male SL residents was measured at an altitude of 50 m and again at 4300 m. The subjects' ages, heights, and weights (mean ± SE) were 22±1 yr, 177±7 cm and 78±2kg, respectively. The subjects' \(\dot V_{O_{2\max } } \) ranged from 36 to 60 ml·kg−1·min−1 (mean ± SE=48±1) and the individual values were normally distributed within this range. Likewise, the decrement in \(\dot V_{O_{2\max } } \) at HA was normally distributed from 3 ml·kg−1·min−1 (9% \(\dot V_{O_{2\max } } \) at SL) to 29 ml·kg−1·min−1 (54% \(\dot V_{O_{2\max } } \) at SL), and averaged 13±1 ml·kg−1·min−1 (27±1% \(\dot V_{O_{2\max } } \) at SL). The linear correlation coefficient between aerobic fitness and the magnitude of the decrement in \(\dot V_{O_{2\max } } \) at HA expressed in absolute terms was r=0.56, or expressed as % \(\dot V_{O_{2\max } } \) at SL was r=0.30; both were statistically significant (p<0.05). Therefore, only 31 and 9%, respectively, of the variability in the decrement at HA could be attributed to the \(\dot V_{O_{2\max } } \) at SL. Thus, while the more aerobically fit individuals do tend to suffer a larger decrement in maximal aerobic power at altitude, the level of aerobic fitness per se accounts for a relatively small amount of the variability between individuals in this decrement.
Active Advice Seeking for Inverse Reinforcement Learning

Intelligent systems that interact with humans typically require input in the form of demonstrations and/or advice for optimal decision making. In more traditional systems, such interactions require detailed and tedious effort on the part of the human expert. Alternatively, active learning systems allow for incremental acquisition of the demonstrations from the human expert where the learning system generates the queries. However, active learning allows for only labeled examples as input, significantly restricting the interaction between expert and learning algorithm. Advice-based learning systems increase the expressiveness of the interaction, but typically require all the advice about the domain in advance. By combining active learning and advice-based learning, we consider the problem of actively soliciting human advice. We present the algorithm in an inverse reinforcement learning setting where the utilities are learned from demonstrations. We show empirically the contribution of a more expressive advice over traditional active learning approaches.
A New Generation of Multijunction Thermal Current Converters

Multijunction thermal converters (MJTCs) are in routine use at the National Institute of Standards and Technology for ac voltage measurements at levels from 250 mV to 60 V, over the frequency range from 10 Hz to 100 MHz. The use of these devices has resulted in reductions in uncertainty of as much as 60% at some points in the voltage parameter space. A new generation of MJTCs, optimized for ac current metrology, promises to accomplish much the same results over the parameter space for ac current transfer difference. This paper describes the motivation for this project, the new designs under consideration, and the results of the work.
Glycan-protein interactions in viral pathogenesis.

The surfaces of host cells and viruses are decorated by complex glycans, which play multifaceted roles in the dynamic interplay between the virus and the host including viral entry into host cell, modulation of proteolytic cleavage of viral proteins, recognition and neutralization of virus by host immune system. These roles are mediated by specific multivalent interactions of glycans with their cognate proteins (generally termed as glycan-binding proteins or GBPs or lectins). The advances in tools and technologies to chemically synthesize and structurally characterize glycans and glycan–GBP interactions have offered several insights into the role of glycan–GBP interactions in viral pathogenesis and have presented opportunities to target these interactions for novel antiviral therapeutic or vaccine strategies. This review covers aspects of role of host cell surface glycan receptors and viral surface glycans in viral pathogenesis and offers perspectives on how to employ various analytical tools to target glycan–GBP interactions.
Prolonged high relief in the northern Cordilleran orogenic front during middle and late Eocene extension based on stable isotope paleoaltimetry

Abstract The paleoelevation and size of the North America Cordilleran orogen during the late Cretaceous–Paleogene contractional and subsequent extensional tectonics remain enigmatic. We present new estimates of paleorelief of the northern Cordilleran orogenic front during the middle and late Eocene using oxygen isotope compositions of unaltered molluscan fossils and paleosol carbonates in the Kishenehn basin. Bounded by several mountains ranges to the east, the Kishenehn basin was a half graben developed during middle Eocene to early Miocene collapse of the Cordilleran orogen. These mollusk taxa include three sympatric groups with affinities to wet tropical, semi-arid subtropical, and temperate environments. Our reconstructed surface water δ18O values vary between −19.8‰ and −6.3‰ (VSMOW) during the middle and late Eocene. The large differences in paleoenvironments and surface water δ18O values suggest that the catchment of the Kishenehn basin was at variable elevation. The estimated paleorelief between the basin and the surrounding mountains, based on both Rayleigh condensation model and predictions of Eocene precipitation isotope values using an isotope-enabled global climate model, is ∼4 km, and the basin floor was
Minimax and minimax projection designs using clustering

Minimax designs provide a uniform coverage of a design space X⊆Rp by minimizing the maximum distance from any point in this space to its nearest design point. Although minimax designs have many use...
The Value of Secretin-Enhanced MRCP in Patients With Recurrent Acute Pancreatitis

OBJECTIVE. The purpose of this study is to assess the additional value of secretin-enhanced MRCP over conventional (non–secretin-enhanced) MRCP in diagnosing disease in patients with recurrent acute pancreatitis. MATERIALS AND METHODS. A retrospective review of a radiology database found 72 patients with recurrent acute pancreatitis who had secretin-enhanced MRCP and ERCP correlation within 3 months of each other between January 2007 and December 2011. Of these patients, 54 had no history of pancreatic tumor or surgery and underwent MRI more than 3 months after an episode of acute pancreatitis. In addition, 57 age- and sex-matched control subjects with secretin-enhanced MRCP and ERCP correlation and without a diagnosis of recurrent acute pancreatitis or chronic pancreatitis were enrolled as the control group. All studies were anonymized, and secretin-enhanced MRCP images (image set A) were separated from conventional 2D and 3D MRCP and T2-weighted images (image set B). Image sets A and B for each patient ...
Immigration Enforcement and Domination: An Indirect Argument for Much More Open Borders

Normative reflection on the ethics of migration has tended to remain at the level of abstract principle with limited attention to the practice of immigration administration and enforcement. This pa...
The PAS Domain-Containing Protein HeuR Regulates Heme Uptake in Campylobacter jejuni

ABSTRACT Campylobacter jejuni is a leading cause of bacterially derived gastroenteritis. A previous mutant screen demonstrated that the heme uptake system (Chu) is required for full colonization of the chicken gastrointestinal tract. Subsequent work identified a PAS domain-containing regulator, termed HeuR, as being required for chicken colonization. Here we confirm that both the heme uptake system and HeuR are required for full chicken gastrointestinal tract colonization, with the heuR mutant being particularly affected during competition with wild-type C. jejuni. Transcriptomic analysis identified the chu genes—and those encoding other iron uptake systems—as regulatory targets of HeuR. Purified HeuR bound the chuZA promoter region in electrophoretic mobility shift assays. Consistent with a role for HeuR in chu expression, heuR mutants were unable to efficiently use heme as a source of iron under iron-limiting conditions, and mutants exhibited decreased levels of cell-associated iron by mass spectrometry. Finally, we demonstrate that an heuR mutant of C. jejuni is resistant to hydrogen peroxide and that this resistance correlates to elevated levels of catalase activity. These results indicate that HeuR directly and positively regulates iron acquisition from heme and negatively impacts catalase activity by an as yet unidentified mechanism in C. jejuni. IMPORTANCE Annually, Campylobacter jejuni causes millions of gastrointestinal infections in the United States, due primarily to its ability to reside within the gastrointestinal tracts of poultry, where it can be released during processing and contaminate meat. In the developing world, humans are often infected by consuming contaminated water or by direct contact with livestock. Following consumption of contaminated food or water, humans develop disease that is characterized by mild to severe diarrhea. There is a need to understand both colonization of chickens, to make food safer, and colonization of humans, to better understand disease. Here we demonstrate that to efficiently colonize a host, C. jejuni requires iron from heme, which is regulated by the protein HeuR. Understanding how HeuR functions, we can develop ways to inhibit its function and reduce iron acquisition during colonization, potentially reducing C. jejuni in the avian host, which would make food safer, or limiting human colonization.
Local Sensitivities of the Gulf Stream Separation

AbstractRobust and accurate Gulf Stream separation remains an unsolved problem in general circulation modeling whose resolution will positively impact the ocean and climate modeling communities. Oceanographic literature does not face a shortage of plausible hypotheses that attempt to explain the dynamics of the Gulf Stream separation, yet a single theory that the community agrees on is missing. In this paper, the authors investigate the impact of the deep western boundary current (DWBC), coastline curvature, and continental shelf steepening on the Gulf Stream separation within regional configurations of the Massachusetts Institute of Technology General Circulation Model. Artificial modifications to the regional bathymetry are introduced to investigate the sensitivity of the separation to each of these factors. Metrics for subsurface separation detection confirm the direct link between flow separation and the surface expression of the Gulf Stream in the Mid-Atlantic Bight. It is shown that the Gulf Stream ...
Counting Conformal Correlators

We introduce simple group-theoretic techniques for classifying conformallyinvariant tensor structures. With them, we classify tensor structures of general n-point functions of non-conserved operators, and n ≥ 4-point functions of general conserved currents, with or without permutation symmetries, and in any spacetime dimension d. Our techniques are useful for bootstrap applications. The rules we derive simultaneously count tensor structures for flat-space scattering amplitudes in d + 1 dimensions.
Low Data Drug Discovery with One-Shot Learning

Recent advances in machine learning have made significant contributions to drug discovery. Deep neural networks in particular have been demonstrated to provide significant boosts in predictive power when inferring the properties and activities of small-molecule compounds (Ma, J. et al. J. Chem. Inf. Model. 2015, 55, 263–274). However, the applicability of these techniques has been limited by the requirement for large amounts of training data. In this work, we demonstrate how one-shot learning can be used to significantly lower the amounts of data required to make meaningful predictions in drug discovery applications. We introduce a new architecture, the iterative refinement long short-term memory, that, when combined with graph convolutional neural networks, significantly improves learning of meaningful distance metrics over small-molecules. We open source all models introduced in this work as part of DeepChem, an open-source framework for deep-learning in drug discovery (Ramsundar, B. deepchem.io. https:...
Lattice parameters guide superconductivity in iron-arsenides.

The discovery of superconducting materials has led to their use in technological marvels such as magnetic-field sensors in MRI machines, powerful research magnets, short transmission cables, and high-speed trains. Despite such applications, the uses of superconductors are not widespread because they function much below room-temperature, hence the costly cooling. Since the discovery of Cu- and Fe-based high-temperature superconductors (HTS), much intense effort has tried to explain and understand the superconducting phenomenon. While no exact explanations are given, several trends are reported in relation to the materials basis in magnetism and spin excitations. In fact, most HTS have antiferromagnetic undoped 'parent' materials that undergo a superconducting transition upon small chemical substitutions in them. As it is currently unclear which 'dopants' can favor superconductivity, this manuscript investigates crystal structure changes upon chemical substitutions, to find clues in lattice parameters for the superconducting occurrence. We review the chemical substitution effects on the crystal lattice of iron-arsenide-based crystals (2008 to present). We note that (a) HTS compounds have nearly tetragonal structures with a-lattice parameter close to 4 A, and (b) superconductivity can depend strongly on the c-lattice parameter changes with chemical substitution. For example, a decrease in c-lattice parameter is required to induce 'in-plane' superconductivity. The review of lattice parameter trends in iron-arsenides presented here should guide synthesis of new materials and provoke theoretical input, giving clues for HTS.
New square-root smoothing algorithms

This paper presents new square-root smoothing algorithms for the three best-known smoothing formulas: (1) Rauch-Tung-Striebel (RTS) formulas, (2) Desai-Weinert-Yusypchuk (DWY) formulas, called backward RTS formulas, and (3) Mayne-Fraser (MF) formulas, called two-filter formulas. The main feature of the new algorithms is that they use unitary rotations to replace all matrix inversion and backsubstitution steps common in earlier algorithms with unitary operations; this feature enables more efficient systolic array and parallel implementations and leads to algorithms with better numerical stability and conditioning properties.
INFLUENCE OF SPIN-ORBIT INTERACTION ON THE TRANSPORT PROCESSES IN FERROMAGNETIC NICKEL ALLOYS, IN THE PRESENCE OF A DEGENERACY OF THE 3D BAND

Abstract Assuming that two of the five branches of the 3d band intersect, it is shown that singularities result in the transport properties when such an intersection happens to occur at the Fermi level. The “ferromagnetic anisotropy of resistivity” Δϱ/ϱ0 (often called magnetoresistance effect) is expected to have a strong maximum; using Born approximation for impurity scattering, and simple models of the 3d and 4s bands, a detailed computation provides an order of magnitude of 20% for the value of Δϱ/ϱ0 at the maximum. On the other hand, assuming the validity of current theories of the “extraordinary Hall conductivity” γ HS due to Smit or to Karplus and Luttinger, γ HS may be expected to change sign. This is precisely the behaviour of Δϱ/ϱ0 and γ HS observed by Smit in Co-Ni and Fe-Ni alloys, for an electron concentration equal to 27.7 electrons per atom.
Associative Pattern Recognition Through Macro-molecular Self-Assembly

We show that macro-molecular self-assembly can recognize and classify high-dimensional patterns in the concentrations of N distinct molecular species. Similar to associative neural networks, the recognition here leverages dynamical attractors to recognize and reconstruct partially corrupted patterns. Traditional parameters of pattern recognition theory, such as sparsity, fidelity, and capacity are related to physical parameters, such as nucleation barriers, interaction range, and non-equilibrium assembly forces. Notably, we find that self-assembly bears greater similarity to continuous attractor neural networks, such as place cell networks that store spatial memories, rather than discrete memory networks. This relationship suggests that features and trade-offs seen here are not tied to details of self-assembly or neural network models but are instead intrinsic to associative pattern recognition carried out through short-ranged interactions.
Near atomically smooth alkali antimonide photocathode thin films

Nano-roughness is one of the major factors degrading the emittance of electron beams that can be generated by high efficiency photocathodes, such as the thermally reacted alkali antimonide thin films. In this paper, we demonstrate a co-deposition based method for producing alkali antimonide cathodes that produce near atomic smoothness with high reproducibility. We calculate the effect of the surface roughness on the emittance and show that such smooth cathode surfaces are essential for operation of alkali antimonide cathodes in high field, low emittance radio frequency electron guns and to obtain ultracold electrons for ultrafast electron diffraction applications.
Equilibrium reconstruction with 3D eddy currents in the Lithium Tokamak eXperiment

Axisymmetric free-boundary equilibrium reconstructions of tokamak plasmas in the Lithium Tokamak eXperiment (LTX) are performed using the PSI-Tri equilibrium code. Reconstructions in LTX are complicated by the presence of long-lived non-axisymmetric eddy currents generated by a vacuum vessel and first wall structures. To account for this effect, reconstructions are performed with additional toroidal current sources in these conducting regions. The eddy current sources are fixed in their poloidal distributions, but their magnitude is adjusted as part of the full reconstruction. Eddy distributions are computed by toroidally averaging currents, generated by coupling to vacuum field coils, from a simplified 3D filament model of important conducting structures. The full 3D eddy current fields are also used to enable the inclusion of local magnetic field measurements, which have strong 3D eddy current pick-up, as reconstruction constraints. Using this method, equilibrium reconstruction yields good agreement wit...
The Heterogeneity of Board-Level Sustainability Committees and Corporate Social Performance

This paper explores an increasingly prevalent element of board-level commitment to sustainability. We propose a theoretical framework under which the existence and associated actions of board-level sustainability committees are motivated by shared value creation, where the interests of a diverse group of stakeholders are satisfied and sufficient profit is achieved. Using hand-collected data, we find that sustainability committees are heterogeneous in focus and vary in their effectiveness. Specifically, we disaggregate the sustainability committee construct based on stakeholder group focus (i.e., community, employee, environment, and consumer/supplier) and find that associations between sustainability committees and performance outcomes are stronger when committees focused on a specific stakeholder group are paired with relevant performance outcomes. We generally find that sustainability committees are effective at impacting relevant strengths, but do not mitigate relevant concerns. These results are consistent with the shared value framework, where committees both generate value by pursuing sustainability-related opportunities and protect value by monitoring, but not necessarily mitigating sustainability-related risks. Univariate tests suggest that effective committees are also larger, more independent, and meet more frequently. Finally, we propose a new method to classify industries based on their sensitivity to certain stakeholder groups and find that the effectiveness of committees focused on specific stakeholders is more pronounced in industries that are sensitive to these stakeholders.
Rat animal models for screening medications to treat alcohol use disorders

The purpose of this review is to present animal research models that can be used to screen and/or repurpose medications for the treatment of alcohol abuse and dependence. The focus will be on rats and in particular selectively bred rats. Brief introductions discuss various aspects of the clinical picture, which provide characteristics of individuals with alcohol use disorders (AUDs) to model in animals. Following this, multiple selectively bred rat lines will be described and evaluated in the context of animal models used to screen medications to treat AUDs. Next, common behavioral tests for drug efficacy will be discussed particularly as they relate to stages in the addiction cycle. Tables highlighting studies that have tested the effects of compounds using the respective techniques are included. Wherever possible the Tables are organized chronologically in ascending order to describe changes in the focus of research on AUDs over time. In general, high ethanol-consuming selectively bred rats have been used to test a wide range of compounds. Older studies usually followed neurobiological findings in the selected lines that supported an association with a propensity for high ethanol intake. Most of these tests evaluated the compound's effects on the maintenance of ethanol drinking. Very few compounds have been tested during ethanol-seeking and/or relapse and fewer still have assessed their effects during the acquisition of AUDs. Overall, while a substantial number of neurotransmitter and neuromodulatory system targets have been assessed; the roles of sex- and age-of-animal, as well as the acquisition of AUDs, ethanol-seeking and relapse continue to be factors and behaviors needing further study. This article is part of the Special Issue entitled "Alcoholism".
A Volcanic Hydrogen Habitable Zone

The classical habitable zone (HZ) is the circular region around a star in which liquid water could exist on the surface of a rocky planet. The outer edge of the traditional N2–CO2–H2O HZ extends out to nearly ~1.7 au in our solar system, beyond which condensation and scattering by CO2 outstrips its greenhouse capacity. Here, we show that volcanic outgassing of atmospheric H2 can extend the outer edge of the HZ to ~2.4 au in our solar system. This wider volcanic-hydrogen HZ (N2–CO2–H2O–H2) can be sustained as long as volcanic H2 output offsets its escape from the top of the atmosphere. We use a single-column radiative-convective climate model to compute the HZ limits of this volcanic hydrogen HZ for hydrogen concentrations between 1% and 50%, assuming diffusion-limited atmospheric escape. At a hydrogen concentration of 50%, the effective stellar flux required to support the outer edge decreases by ~35%–60% for M–A stars. The corresponding orbital distances increase by ~30%–60%. The inner edge of this HZ only moves out ~0.1%–4% relative to the classical HZ because H2 warming is reduced in dense H2O atmospheres. The atmospheric scale heights of such volcanic H2 atmospheres near the outer edge of the HZ also increase, facilitating remote detection of atmospheric signatures.
Low order physical models of vertical axis wind turbines

In order to examine the ability of low-order physical models of vertical axis wind turbines to accurately reproduce key flow characteristics, experimental data are presented for the mean flow patterns and turbulence spectra associated with pairs of rotating turbines, rotating solid cylinders, and stationary porous flat plates (of both uniform and non-uniform porosities). The experiments were conducted at a nominal model-diameter Reynolds number of 600 and rotation tip speed ratios between 0 and 6. By comparing the induced flow fields of the different models both qualitatively and quantitatively, it was concluded that the two dimensional horizontal mean flow fields induced by the porous flat plates were quantitatively similar to those induced by slowly rotating turbine models. However, over the range of the experimental parameters examined, the porous flat plates were unable to produce vertical flows similar to those associated with the slowly rotating turbine models. Conversely, the moderately rotating cy...
Beyond Talagrand functions: new lower bounds for testing monotonicity and unateness

We prove a lower bound of Ω(n1/3) for the query complexity of any two-sided and adaptive algorithm that tests whether an unknown Boolean function f:{0,1}n→ {0,1} is monotone versus far from monotone. This improves the recent lower bound of Ω(n1/4) for the same problem by Belovs and Blais (STOC'16). Our result builds on a new family of random Boolean functions that can be viewed as a two-level extension of Talagrand's random DNFs. Beyond monotonicity we prove a lower bound of Ω(√n) for two-sided, adaptive algorithms and a lower bound of Ω(n) for one-sided, non-adaptive algorithms for testing unateness, a natural generalization of monotonicity. The latter matches the linear upper bounds by Khot and Shinkar (RANDOM'16) and by Baleshzar, Chakrabarty, Pallavoor, Raskhodnikova, and Seshadhri (2017).
"Half Art": Baudelaire's Le Peintre de la vie moderne

This article considers Baudelaire's essay Le Peintre de la vie moderne as a possible response to the question of why art matters. Baudelaire's exhilarating innovation is to downgrade the significance of eternal value in art, in favour of what he designates its other half, the fleeting presentness that is modernity. Baudelaire explores this idea through a mock-anonymous celebration of the artist Constantin Guys, referred to as M. G., whose prolific sketches, done at speed, for rapid journal publication, chart the day-by-day miniscule changes in the appearances of the city. Guys's pictures — the art of modernity — give to the fleeting moment a second life, and ‘translate’ into a different medium — from sight to (mental) impression to its ‘rebirth’ as a sketch — what would otherwise be lost in its passing.
General scaling relations for locomotion in granular media

Inspired by dynamic similarity in fluid systems, we have derived a general dimensionless form for locomotion in granular materials, which is validated in experiments and discrete element method (DEM) simulations. The form instructs how to scale size, mass, and driving parameters in order to relate dynamic behaviors of different locomotors in the same granular media. The scaling can be derived by assuming intrusion forces arise from resistive force theory or equivalently by assuming the granular material behaves as a continuum obeying a frictional yield criterion. The scalings are experimentally confirmed using pairs of wheels of various shapes and sizes under many driving conditions in a common sand bed. We discuss why the two models provide such a robust set of scaling laws even though they neglect a number of the complexities of granular rheology. Motivated by potential extraplanetary applications, the dimensionless form also implies a way to predict wheel performance in one ambient gravity based on tests in a different ambient gravity. We confirm this using DEM simulations, which show that scaling relations are satisfied over an array of driving modes even when gravity differs between scaled tests.