cssi/SciSciGPT-SciSciNet huggingface dataset:
Functional Transparency for Structured Data: a Game-Theoretic Approach.

We provide a new approach to training neural models to exhibit transparency in a well-defined, functional manner. Our approach naturally operates over structured data and tailors the predictor, functionally, towards a chosen family of (local) witnesses. The estimation problem is setup as a co-operative game between an unrestricted predictor such as a neural network, and a set of witnesses chosen from the desired transparent family. The goal of the witnesses is to highlight, locally, how well the predictor conforms to the chosen family of functions, while the predictor is trained to minimize the highlighted discrepancy. We emphasize that the predictor remains globally powerful as it is only encouraged to agree locally with locally adapted witnesses. We analyze the effect of the proposed approach, provide example formulations in the context of deep graph and sequence models, and empirically illustrate the idea in chemical property prediction, temporal modeling, and molecule representation learning.
VeriSFQ: A Semi-formal Verification Framework and Benchmark for Single Flux Quantum Technology

In this paper, we propose a semi-formal verification framework for single-flux quantum (SFQ) circuits called VeriSFQ, using the Universal Verification Methodology (UVM) standard. The considered SFQ technology is superconducting digital electronic devices that operate at cryogenic temperatures with active circuit elements called the Josephson junction, which operate at high switching speeds and low switching energy - allowing SFQ circuits to operate at frequencies over 300 gigahertz. Due to key differences between SFQ and CMOS logic, verification techniques for the former are not as advanced as the latter. Thus, it is crucial to develop efficient verification techniques as the complexity of SFQ circuits scales. The VeriSFQ framework focuses on verifying the key circuit and gate-level properties of $\mathrm{SFQ}$ logic: fanout, gate-level pipeline, path balancing, and input-to-output latency. The combinational circuits considered in analyzing the performance of VeriSFQ are: Kogge-Stone adders (KSA), array multipliers, integer dividers, and select ISCAS’85 combinational benchmark circuits. Methods of introducing bugs into SFQ circuit designs for verification detection were experimented with - including stuck-at faults, fanout errors, unbalanced paths, and functional bugs like incorrect logic gates. In addition, we propose an SFQ verification benchmark consisting of combinational SFQ circuits that exemplify SFQ logic properties and present the performance of the VeriSFQ framework on these benchmark circuits. The portability and reusability of the UVM standard allows the VeriSFQ framework to serve as a foundation for future SFQ semi-formal verification techniques.
A longitudinal study of the effects of age, sex and race on body composition in chronic kidney disease

Background Chronic kidney disease (CKD) is characterized by accelerated aging, but the age-related changes in body composition and its modification by sex and race are unclear. Methods We assembled a cohort of 516 patients with CKD and 45 healthy controls and serially measured body composition using air-displacement plethysmography for up to 6 years. Mixed models were used to evaluate simultaneously the baseline and longitudinal changes in body composition as influenced by age, sex and race. Results Compared with healthy controls, patients with CKD had a greater weight, body mass index (BMI), fat mass (FM) and percent body fat (BF%), but the changes over time in body composition were similar. Older age (>60 years) was a strong determinant of loss of weight, BMI, FM and fat-free mass (FFM), but not BF%. Compared with non-blacks, blacks had a higher FFM at baseline, but they lost FFM more rapidly. Compared with women, men had an accelerated loss of FFM and accumulation of FM. Taking interactions into account, we found that young black men had no significant change in weight due to the loss of FFM and the accumulation of FM, thereby masking obesity by conventional measurements. Conclusion Among patients with CKD, the changes in body composition are influenced by age, sex and race. Young black men have changes in body composition that may remain undetectable by conventional methods thus masking the occurrence of obesity.
Demonstration of 99% CO2 removal from coal flue gas by amine scrubbing

Abstract A post-combustion CO2 capture campaign was conducted at the National Carbon Capture Center (NCCC) with 5 m PZ (piperazine) using the advanced flash stripper configuration. 68 steady-state runs were identified and 90% or to 99.1% CO2 removal was achieved with a 12 m of packing in the absorber. A 20% increase in solvent rate enhanced CO2 removal from 90% to 99% and the rich loading decreased from 0.40 to 0.38 mol CO2/mol alkalinity. With high removal, the temperature profile from modeling indicated there was a mass transfer pinch in the absorber, which means 12 m packing is more than needed even for 99% removal. The rich loading did not decrease significantly at high CO2 removal, therefore the energy cost for regeneration remained practically unchanged. The material balance around the absorber based on CO2 loaded calculated from density and viscosity closed within 2.3%. The rate-based Aspen Plus® model under-predicted the number of transfer units in the absorber by an average of 16%. This was caused by the difference between CO2 concentration measured by titration and calculated from density and viscosity. With the advanced flash stripper (AFS), the process heat duty was between 1.9 and 2.5 GJ/t CO2 and did not increase more than 5% at higher CO2 removal. Due to the fast reaction kinetics of PZ, the 12 m absorber was overdesigned for 99% CO2 removal and the rich loading was unchanged at high removal. Further, the superior design of the AFS recovered the latent heat of water vapor and minimized the energy consumption for solvent regeneration. Therefore, it is feasible to capture 99% of the CO2 from coal-fired flue gas with PZ scrubbing at a reasonable energy cost.
Evolution of the lithosphere in the Indian Ocean from combined earthquake and ambient noise tomography

Rayleigh wave dispersion extracted from ambient seismic noise has been widely used to image crustal and uppermost mantle structure. Applications of this approach in continental settings are abundant, but there have been relatively few studies within ocean basins. By cross-correlating ambient noise recorded at broadband seismic stations around the Indian Ocean, we demonstrate the feasibility of extracting high-quality, long-period (10-30 mHz) Rayleigh waves that traverse the entire ocean basin. High-quality Rayleigh wave cross-correlation functions can be obtained from stacking waveforms over less than two years at land stations and less than four years at island stations. We show that adding the dispersion information extracted from ambient noise to a global earthquake data set can improve the resolution of phase velocity maps by about 20% in the northern Indian Ocean, where the station distribution is the best. We find that a plate cooling model with a potential temperature of 1450° C and plate thickness of 125 km can fit both the seismic observations and seafloor topography. The Seychelles-Mascarene Plateau is characterized by anomalously slow velocity at 30 mHz. The inclusion of ambient noise data in the tomographic inversion shifts the slow velocity anomaly into better agreement with the topographic relief, allowing us to estimate its crustal thickness and confirm that the plateau's elevation is supported by thick crust. The 10 and 20 mHz phase velocity maps show a strong asymmetry across the Central Indian Ridge that is best explained by eastward asthenospheric flow emanating from nearby hotspots.
Readability and research impact

Abstract I ask whether the writing quality affects a research paper’s impact. Using papers published in the American Economic Review between 2000 and 2009 I apply a standardized readability metric to score the quality of the writing of the introduction section of each paper. Using citation counts to measure research’s impact, I show a statistically significant relationship between the two. The hardest to read papers suffer a reduction in citations by up to 1 5 of a standard deviation.
Wearable Enzymatic Alcohol Biosensor

Transdermal alcohol biosensors have the ability to detect the alcohol that emanates from the bloodstream and diffuses through the skin. However, previous biosensors have suffered from long-term fouling of the sensor element and drift in the resulting sensor readings over time. Here, we report a wearable alcohol sensor platform that solves the problem of sensor fouling by enabling drift-free signals in vivo for up to 24 h and an interchangeable cartridge connection that enables consecutive days of measurement. We demonstrate how alcohol oxidase enzyme and Prussian Blue can be combined to prevent baseline drift above 25 nA, enabling sensitive detection of transdermal alcohol. Laboratory characterization of the enzymatic alcohol sensor demonstrates that the sensor is mass-transfer-limited by a diffusion-limiting membrane of lower permeability than human skin and a linear sensor range between 0 mM and 50 mM. Further, we show continuous transdermal alcohol data recorded with a human subject for two consecutive days. The non-invasive sensor presented here is an objective alternative to the self-reports used commonly to quantify alcohol consumption in research studies.
Interpretation of Near-Infrared Spectroscopy (NIRS) Signals in Skeletal Muscle.

Near-infrared spectroscopy (NIRS) uses the relative absorption of light at 850 and 760 nm to determine skeletal muscle oxygen saturation. Previous studies have used the ratio of both signals to report muscle oxygen saturation. Purpose: The purpose of this pilot study is to assess the different approaches used to represent muscle oxygen saturation and to evaluate the pulsations of oxygenated hemoglobin/myoglobin (O2heme) and deoxygenated hemoglobin/myoglobin (Heme) signals. Method: Twelve participants, aged 20–29 years, were tested on the forearm flexor muscles using continuous-wave NIRS at rest. Measurements were taken during 2–3 min rest, physiological calibration (5 min ischemia), and reperfusion. Ten participants were included in the study analysis. Results: There was a significant difference in pulse size between O2heme and Heme signals at the three locations (p < 0.05). Resting oxygen saturation was 58.8% + 9.2%, 69.6% + 3.9%, and 89.2% + 6.9% when calibrated using O2heme, the tissue oxygenation/saturation index (TSI), and Heme, respectively. Conclusion: The difference in magnitude of O2heme and Heme pulses with each heartbeat might suggest different anatomical locations of these signals, for which calibrating with just one of the signals instead of the ratio of both is proposed. Calculations of physiological calibration must account for increased blood volume in the tissue because of the changes in blood volume, which appear to be primarily from the O2heme signal. Resting oxygen levels calibrated with Heme agree with theoretical oxygen saturation.
A Product Inequality for Extreme Distances.

Abstract Let p 1 , … , p n be n distinct points in the plane, and assume that the minimum inter-point distance occurs s min times, while the maximum inter-point distance occurs s max times. It is shown that s min s max ≤ 9 8 n 2 + O ( n ) ; this settles a conjecture of Erdős and Pach (1990).
A Cellular Taxonomy of the Bone Marrow Stroma in Homeostasis and Leukemia

Summary Stroma is a poorly defined non-parenchymal component of virtually every organ with key roles in organ development, homeostasis, and repair. Studies of the bone marrow stroma have defined individual populations in the stem cell niche regulating hematopoietic regeneration and capable of initiating leukemia. Here, we use single-cell RNA sequencing (scRNA-seq) to define a cellular taxonomy of the mouse bone marrow stroma and its perturbation by malignancy. We identified seventeen stromal subsets expressing distinct hematopoietic regulatory genes spanning new fibroblastic and osteoblastic subpopulations including distinct osteoblast differentiation trajectories. Emerging acute myeloid leukemia impaired mesenchymal osteogenic differentiation and reduced regulatory molecules necessary for normal hematopoiesis. These data suggest that tissue stroma responds to malignant cells by disadvantaging normal parenchymal cells. Our taxonomy of the stromal compartment provides a comprehensive bone marrow cell census and experimental support for cancer cell crosstalk with specific stromal elements to impair normal tissue function and thereby enable emergent cancer.
Novel syntheses of 3-anilino-pyrazin-2(1H)-ones and 3-anilino-quinoxalin-2-(1H)-ones via microwave-mediated Smiles rearrangement

In this Letter, we report a novel approach to the preparation of 3-anilino-pyrazin-2(1H)-ones and 3-anilino-quinoxalin-2(1H)-ones from the corresponding 3-halo pyrazin-2-amines and 3-haloquinoxalin-2-amines, using a microwave-mediated Smiles rearrangement.
A homologous enolate Truce–Smiles rearrangement

During preparation of a series of diphenyl ethers it was observed that displacement of an activated aryl fluoride with ortho-hydroxyacetophenone afforded a product that was C-arylated adjacent to the ketone. Evidence suggested this product was formed by Smiles rearrangement of an O-arylated intermediate.
Glutamatergic facilitation of neural responses in MT enhances motion perception in humans.

Abstract There is large individual variability in human neural responses and perceptual abilities. The factors that give rise to these individual differences, however, remain largely unknown. To examine these factors, we measured fMRI responses to moving gratings in the motion-selective region MT, and perceptual duration thresholds for motion direction discrimination. Further, we acquired MR spectroscopy data, which allowed us to quantify an index of neurotransmitter levels in the region of area MT. These three measurements were conducted in separate experimental sessions within the same group of male and female subjects. We show that stronger Glx (glutamate + glutamine) signals in the MT region are associated with both higher fMRI responses and superior psychophysical task performance. Our results suggest that greater baseline levels of glutamate within MT facilitate motion perception by increasing neural responses in this region.
Spectroscopic experiments on the role of Me3SiCl in lithium dialkylamide deprotonations

Low temperature 1H and 7Li NMR studies on LDA and LTMP in the presence of TMS-Cl implicate this additive as a finite source of LiCl, a key component of in situ quenching reactions of ketones.
Alkyne Metathesis as a New Synthetic Tool: Ring-Closing, Ring-Opening, and Acyclic.

Conceptually and mechanistically (!) the metathesis of disubstituted alkynes in the presence of molybdenum or tungsten catalysts (see scheme) is related to alkene metathesis. With skillful experimentation and careful selection of substrate, alkyne metathesis can result in both ring opening/ring closing and the formation of high molecular weight polymers.
A species-specific nematocide that results in terminal embryogenesis.

Nematode-insect interactions are ubiquitous, complex, and constantly changing as the host and nematode coevolve. The entomophilic nematode Pristionchus pacificus is found on a myriad beetle species worldwide, though the molecular dynamics of this relationship are largely unknown. To better understand how host cues affect P. pacificus embryogenesis, we characterized the threshold of sensitivity to the pheromone ( Z )-7-tetradecen-2-one (ZTDO) by determining the minimum exposure duration and developmental window that results in P. pacificus embryonic lethality. We found early-stage embryos exposed to volatile ZTDO for as few as four hours all display terminal embryogenesis, characterized by punctuated development up to 48 hours later, with abnormal morphology and limited cavity formation. To determine if the pheromone arrests pre-hatching development by suffocating or permeabilizing the eggshells, we raised embryos under anoxic conditions as well as examined eggshell permeability using the lipophilic dye FM4-64. We found that asphyxiating the embryos arrested embryogenesis in a reversible manner but did not phenocopy the effects of ZTDO exposure, whereas the ZTDO-induced disruption of embryogenesis did correlate with increased eggshell permeability. The effects of ZTDO are also highly specific, as other lipid insect compounds do not produce any detectable embryocidal effect. The high specificity and unusual teratogenic effect of ZTDO may be important in mediating the host-nematode relationship by regulating P. pacificus development.
Reactions of lanthanide atoms with oxygen difluoride and the role of the Ln oxidation state.

Laser-ablated lanthanide metal atoms were condensed with OF2 in excess argon or neon at 4 K. New infrared absorption bands were observed and assigned to the oxidative addition products OLnF2 and OL...
Beyond financial conflicts of interest: Institutional oversight of faculty consulting agreements at schools of medicine and public health.

Importance Approximately one-third of U.S. life sciences faculty engage in industry consulting. Despite reports that consulting contracts often impinge on faculty and university interests, institutional approaches to regulating consulting agreements are largely unknown. Objective To investigate the nature of institutional oversight of faculty consulting contracts at U.S. schools of medicine and public health. Design Structured telephone interviews with institutional administrators. Questions included the nature of oversight for faculty consulting agreements, if any, and views about consulting as a private versus institutional matter. Interviews were analyzed using a structured coding scheme. Setting All accredited schools of medicine and public health in the U.S. Participants Administrators responsible for faculty affairs were identified via internet searches and telephone and email follow-up. The 118 administrators interviewed represented 73% of U.S. schools of medicine and public health, and 75% of those invited to participate. Intervention Structured, 15–30 minute telephone interviews. Main outcomes and measures Prevalence and type of institutional oversight; responses to concerning provisions in consulting agreements; perceptions of institutional oversight. Results One third of institutions (36%) required faculty to submit at least some agreements for institutional review and 36% reviewed contracts upon request, while 35% refused to review contracts. Among institutions with review, there was wide variation the issues covered. The most common topic was intellectual property rights (64%), while only 23% looked at publication rights and 19% for inappropriately broad confidentiality provisions. Six in ten administrators reported they had no power to prevent faculty from signing consulting agreements. Although most respondents identified institutional risks from consulting relationships, many maintained that consulting agreements are “private.” Conclusions and relevance Oversight of faculty consulting agreements at U.S. schools of medicine and public health is inconsistent across institutions and usually not robust. The interests at stake suggest the need for stronger oversight.
A Simulation Framework For Fast Design Space Exploration Of Unmanned Air System Traffic Management Policies

The number of daily small Unmanned Aircraft Systems (sUAS) operations in uncontrolled low altitude airspace is expected to reach into the millions. UAS Traffic Management (UTM) is an emerging concept aiming at the safe and efficient management of such very dense traffic, but few studies are addressing the policies to accommodate such demand and the required ground infrastructure in suburban or urban environments. Searching for the optimal air traffic management policy is a combinatorial optimization problem with intractable complexity when the number of sUAS and the constraints increases. As the demands on the airspace increase and traffic patterns get complicated, it is difficult to forecast the potential low altitude airspace hotspots and the corresponding ground resource requirements. This work presents a Multi-agent Air Traffic and Resource Usage Simulation (MATRUS) framework that aims for fast evaluation of different air traffic management policies and the relationship between policy, environment and resulting traffic patterns. It can also be used as a tool to decide the resource distribution and launch site location in the planning of a next generation smart city. As a case study, detailed comparisons are provided for the sUAS flight time, conflict ratio, cellular communication resource usage, for a managed (centrally coordinated) and unmanaged (free flight) traffic scenario.
The Total Synthesis of 5-Oxo-12(S)-hydroxy-6(E),8(Z),10(E),14(Z)-eicosatetraenoic Acid and Its 8,9-trans-Isomer and Their Identification in Human Platelets

The first total synthesis of 5-oxo-12(S)-hydroxy-6(E),8(Z),10(E), 14(Z)-eicosatetraenoic acid (5-oxo-12-HETE) 6 and its 8-trans-isomer 7 is reported. The synthetic 5-oxo-12-HETE 6 and its 8,9-trans-isomer 7 were used to identify their formation in mixtures of platelets and neutrophils by transcellular metabolism.
Chemical modification of carbon nanotubes

The current worldwide research on carbon nanotubes (CNTs) has been facilitated by unique physico-chemical properties and wide opportunities the CNTs offer for the new field of nanotechnology. The recent studies have shown that, for the efficient use of CNT structural properties, particularly in the engineering of multi-functional materials, the CNTs need to be chemically modified by attachment of functional groups for improving the solubility, processing and compatibility with host materials. While responding to the application needs, chemical modification of carbon nanotubes has quickly emerged as a new research frontier, which is fascinating from not only applied but also fundamental standpoint by permitting studies of chemical reactivity in relation to the nanoscale size and shape of confined structures.
Phenyliodine(III) bis(trifluoroacetate)-mediated oxidation of bisindolylmaleimides to indolo[2,3-a]carbazoles

A novel protocol for the oxidation of bisindolylmaleimides to the corresponding indolo[2,3-a]carbazoles in 15–56% yield with phenyliodine(III) bis(trifluoroacetate) (PIFA) is reported.
Solid phase synthesis of guanidines

Abstract A comparison of guanylating agents 1 and 2 was performed on a series of primary, secondary and aromatic amines in solution and on solid phase resins. Thiourea 1 performed well in solution and on solid supported primary and secondary amines. Pyrazole 2 performed well in each case, except one aniline which failed to react.
Analyses of Neanderthal introgression suggest that Levantine and southern Arabian populations have a shared population history

OBJECTIVES Modern humans are thought to have interbred with Neanderthals in the Near East soon after modern humans dispersed out of Africa. This introgression event likely took place in either the Levant or southern Arabia depending on the dispersal route out of Africa that was followed. In this study, we compare Neanderthal introgression in contemporary Levantine and southern Arabian populations to investigate Neanderthal introgression and to study Near Eastern population history. MATERIALS AND METHODS We analyzed genotyping data on >400,000 autosomal SNPs from seven Levantine and five southern Arabian populations and compared these data to those from populations from around the world including Neanderthal and Denisovan genomes. We used f4 and D statistics to estimate and compare levels of Neanderthal introgression between Levantine, southern Arabian, and comparative global populations. We also identified 1,581 putative Neanderthal-introgressed SNPs within our dataset and analyzed their allele frequencies as a means to compare introgression patterns in Levantine and southern Arabian genomes. RESULTS We find that Levantine and southern Arabian populations have similar levels of Neanderthal introgression to each other but lower levels than other non-Africans. Furthermore, we find that introgressed SNPs have very similar allele frequencies in the Levant and southern Arabia, which indicates that Neanderthal introgression is similarly distributed in Levantine and southern Arabian genomes. DISCUSSION We infer that the ancestors of contemporary Levantine and southern Arabian populations received Neanderthal introgression prior to separating from each other and that there has been extensive gene flow between these populations.
Proteasome dysfunction triggers activation of SKN-1A/Nrf1 by the aspartic protease DDI-1

Proteins perform many important roles in cells, but these molecules can become toxic if they are damaged or are no longer needed. A molecular machine called the proteasome destroys ‘unwanted’ proteins in animal and other eukaryotic cells. If the proteasome stops working properly, unwanted proteins start to accumulate and cells respond by increasing the activity of genes that make proteasomes. A protein called SKN-1 is involved in this response and activates the genes that encode proteasome proteins, but it is not understood how SKN-1 “senses” that proteasomes are not working properly. Here, Lehrbach and Ruvkun used a roundworm called Caenorhabditis elegans to search for new genes that activate SKN-1 when the proteasome’s activity is impaired. The roundworms were genetically engineered to produce a fluorescent protein that indicates when a particular gene needed to make proteasomes is active. Lehrbach and Ruvkun identified some roundworms with mutations that cause the levels of fluorescence to be lower, indicating that SKN-1 was less active in these animals. Further experiments showed that some of these mutations are in genes that encode enzymes called DDI-1 and PNG-1. DDI-1 is able to cut certain proteins, while PNG-1 can remove sugars that are attached to proteins. Therefore, it is likely that these enzymes directly interact with SKN-1 and alter it to activate the genes that produce the proteasome. More work is now needed to understand the details of how modifying SKN-1 changes its activity in cells. In the future, drugs that target DDI-1 or PNG-1 might be used to treat diseases in which proteasome activity is too high or low, including certain cancers and neurodegenerative diseases.
Palladium-mediated ring opening of hydroxycyclopropanes

The palladium-mediated ring opening of substituted cyclopropanols has been found to take place predominantly at the less substituted C−C bond. Thus, sequential application of the titanium-mediated cyclopropanation of esters and the palladium-mediated ring opening of the resulting cyclopropanols provides a convenient method for functionalizing monosubstituted olefins.
A Silicon Tether Approach for Addition of Functionalized Radicals to Chiral α-Hydroxyhydrazones: Diastereoselective Additions of Hydroxymethyl and Vinyl Synthons

Stereocontrolled additions of hydroxymethyl and vinyl groups to chiral alpha-hydroxyhydrazones can be achieved by radical cyclizations using bromomethyl or vinyl radical precursors tethered via a temporary silicon connection. Tin-mediated 5-exo radical cyclization of alpha-hydroxyhydrazones using a silicon-tethered bromomethyl group, followed by oxidative removal of the tether, provides anti-2-hydrazino 1,3-diols in good yield. Tandem thiyl radical addition-cyclization of alpha-hydroxyhydrazones using a silicon-tethered vinyl group, followed by treatment with potassium fluoride, affords acyclic allylic anti-hydrazino alcohols in good yield. The thiyl addition-cyclization method has been successfully extended to the use of alpha,beta-dihydroxyhydrazones without prior protection or hydroxyl differentiation. Diastereoselection in both reaction types increases with increasing A values of the appended groups, consistent with prediction by the Beckwith-Houk model for stereocontrol in 5-hexenyl radical cyclizations.
5-Bromomethyl-4,5-dihydroisoxazoles

The preparation of substituted 4,5-dihydroisoxazoles can be accomplished via the treatment of β,γ-unsaturated oximes with liquid bromine. The reaction provides a convenient route to the highly functionalized title compounds.
A road map to solar neutrino fluxes, neutrino oscillation parameters, and tests for new physics

We analyze all available solar and related reactor neutrino experiments, as well as simulated future 7 Be, pip, and pep solar neutrino experiments. We treat all solar neutrino ∞uxes as free parameters subject to the condition that the total luminosity repre- sented by the neutrinos equals the observed solar luminosity (the 'luminosity constraint'). Existing experiments plus the luminosity constraint show that the pip solar neutrino ∞ux is 1:02§ 0:02 (1ae) times the ∞ux predicted by the BP00 standard solar model; the 7 Be neutrino ∞ux is 0:93 +0:25 i0:63 the predicted ∞ux; and the 8 B ∞ux is 1:01§ 0:04 the predicted ∞ux. The CNO ∞uxes are very poorly determined. The neutrino oscillation parameters are: ¢m 2 = 7:3 +0:4 i0:6 £ 10 i5 eV 2 and tan 2 µ12 = 0:41§ 0:04. We evaluate how accurate fu- ture experiments must be to determine more precisely neutrino oscillation parameters and solar neutrino ∞uxes, and to elucidate the transition from vacuum-dominated to matter- dominated oscillations at low energies. A future 7 Be "ie scattering experiment accurate to §10% can reduce the uncertainty in the experimentally determined 7 Be neutrino ∞ux by a factor of four and the uncertainty in the pi p neutrino ∞ux by a factor of 2.5 (to §0:8%). A future pi p experiment must be accurate to better than §3% to shrink the uncertainty in tan 2 µ12 by more than 15%. The idea that the Sun shines because of nuclear fusion reactions can be tested accurately by comparing the observed photon luminosity of the Sun with the luminosity inferred from measurements of solar neutrino ∞uxes. Based upon quantitative analyses of present and simulated future experiments, we answer the question: Why perform low-energy solar neutrino experiments?
SYNTHESIS OF CARBON NITRIDE

In 1990, Liu and Cohen presented a pseudopotential study of the structural and electronic properties of β-C3N4, a hypothetical compound. The calculated properties of β-C3N4, including bulk modulus and velocity of sound, were found to be comparable to that of diamond suggesting high values for hardness and for thermal conductivity. In this paper, the field of experimental efforts to produce carbon nitride is reviewed. Synthesis of β-C3N4 has been claimed on the basis of diffraction data. However, the overall composition of the materials obtained in these as in most other experiments is not stoichiometric; the N-to-C concentration ratio attained in most cases is [N]/[C] < 1. The likely reasons for this and the dependence of the nitrogen content and bonding on deposition conditions are discussed. The determination of the carbon and nitrogen contents and, more importantly, their contents in specific bonding states is a complex problem to which a significant part of this paper is devoted. Most of the experimental work to date, including those claiming success, applied deposition methods using energetic particles. Among these methods, ion beam deposition (IBD) stands out for its ability to control deposition conditions. We discuss in particular detail our work based on IBD. On the basis of results from electron spectroscopies and computer simulations, a film growth model that includes surface deposition, subplantation and preferential sputtering of nitrogen has been developed. Some future possibilities for the deposition of C-N films are discussed on the basis of this model.
Formation of trithiocyanate in the oxidation of aqueous thiocyanate.

Oxidation of SCN - in acidic media by a deficiency of aqueous chlorine generates a transient UV absorption feature in less than 3 ms. This intermediate has the same spectral and kinetic features as were found in prior studies of the oxidation of SCN - by H 2 O 2 or ClO 2 . The UV absorbance increases strongly with increasing concentration of SCN - but not with increasing [H + ]. These observations are evidence that (SCN) 2 and (SCN) 3 - both contribute to the absorbance and are in equilibrium with each other. Values of the corresponding molar absorptivities and the equilibrium constant are derived. Hydrolysis of (SCN) 2 to HOSCN is shown to have a small equilibrium constant.
Elimination and Activation of Methane and Larger Hydrocarbons

This paper describes a study of hydrocarbon activation and elimination. Important chemical conclusions include the following. There is little evidence for significant agostic interactions between Z...
Simulating the magnetorotational collapse of supermassive stars: Incorporating gas pressure perturbations and different rotation profiles.

Collapsing supermassive stars (SMSs) with masses $M\ensuremath{\gtrsim}{10}^{4--6}{M}_{\ensuremath{\bigodot}}$ have long been speculated to be the seeds that can grow and become supermassive black holes (SMBHs). We previously performed general relativistic magnetohydrodynamic (GRMHD) simulations of marginally stable $\mathrm{\ensuremath{\Gamma}}=4/3$ polytropes uniformly rotating at the mass-shedding limit and endowed initially with a dynamically unimportant dipole magnetic field to model the direct collapse of SMSs. These configurations are supported entirely by thermal radiation pressure and reliably model SMSs with $M\ensuremath{\gtrsim}{10}^{6}{M}_{\ensuremath{\bigodot}}$. We found that around 90% of the initial stellar mass forms a spinning black hole (BH) remnant surrounded by a massive, hot, magnetized torus, which eventually launches a magnetically-driven jet. SMSs could be therefore sources of ultra-long gamma-ray bursts (ULGRBs). Here we perform GRMHD simulations of $\mathrm{\ensuremath{\Gamma}}\ensuremath{\gtrsim}4/3$, polytropes to account for the perturbative role of gas pressure in SMSs with $M\ensuremath{\lesssim}{10}^{6}{M}_{\ensuremath{\bigodot}}$. We also consider different initial stellar rotation profiles. The stars are initially seeded with a dynamically weak dipole magnetic field that is either confined to the stellar interior or extended from its interior into the stellar exterior. We calculate the gravitational wave burst signal for the different cases. We find that the mass of the black hole remnant is 90%--99% of the initial stellar mass, depending sharply on $\mathrm{\ensuremath{\Gamma}}\ensuremath{-}4/3$ as well as on the initial stellar rotation profile. After $t\ensuremath{\sim}250--550M\ensuremath{\approx}1\ensuremath{-}2\ifmmode\times\else\texttimes\fi{}{10}^{3}(M/{10}^{6}{M}_{\ensuremath{\bigodot}})\text{ }\text{ }\mathrm{s}$ following the appearance of the BH horizon, an incipient jet is launched and it lasts for $\ensuremath{\sim}{10}^{4}--{10}^{5}(M/{10}^{6}{M}_{\ensuremath{\bigodot}})\text{ }\text{ }\mathrm{s}$, consistent with the duration of long gamma-ray bursts. Our numerical results suggest that the Blandford-Znajek mechanism powers the incipient jet. They are also in rough agreement with our recently proposed universal model that estimates accretion rates and electromagnetic (Poynting) luminosities that characterize magnetized BH-disk remnant systems that launch a jet. This model helps explain why the outgoing electromagnetic luminosities computed for vastly different BH-disk formation scenarios all reside within a narrow range ($\ensuremath{\sim}{10}^{52\ifmmode\pm\else\textpm\fi{}1}\text{ }\text{ }\mathrm{erg}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$), roughly independent of $M$.
LIKE-SIGN CHARGED HIGGS BOSON PRODUCTION IN e+e– COLLISIONS AT THE NLC

We consider the production of a pair of like-sign charged Higgs bosons in e−e− collisions at the NLC within the context of several electroweak models with extended symmetry breaking sectors. We find that the rate for this process, which proceeds through W–W– fusion, is a very sensitive probe of the nature of these extended Higgs sectors and that the corresponding cross sections can vary by as much as several orders of magnitude at NLC energies.
Bid-Limited Targeting

This article analyzes a mechanism for selling items in auctions in which the auctioneer specifies a cap on the ratio between the maximum and minimum bids that bidders may use in the auctions. Such a mechanism is widely used in online advertising through the caps that companies impose on the minimum and maximum bid multipliers that advertisers may use in targeting. When bidders’ values are independent and identically distributed, this mechanism results in greater revenue than allowing bidders to condition their bids on the targeting information in an arbitrary way and also almost always results in greater revenue than not allowing bidders to target. Choosing the optimal cap on the ratio between the maximum and minimum bids can also be more important than introducing additional competition in the auction. However, if bidders’ values are not identically distributed, pure-strategy equilibria may fail to exist.
Iodine as a novel and efficient reagent for the synthesis of α-aminonitriles by a three-component condensation of carbonyl compounds, amines, and trimethylsilyl cyanide

Abstract A straightforward and general method has been developed for the synthesis of α-aminonitriles by simply combining aldehydes or ketones, amines, and trimethylsilyl cyanides in the presence of a catalytic amount of molecular iodine at room temperature.
5,5-Dimethyl-1,4,2-dioxazoles as versatile aprotic hydroxamic acid protecting groups.

5,5-Dimethyl-1,4,2-dioxazoles are readily installed by transketalization of 2,2-diethoxypropane, where both the NH and OH moieties are protected in a nonprotic form. The dioxazoles are stable to a wide variety of reaction conditions and readily revert back to the hydroxamic acid by treatment with Nafion-H in 2-propanol. The method is applicable to primary, secondary, tertiary, and aromatic hydroxamic acids, and the acidity of the protons adjacent to the dioxazole allows α-functionalization.
On the constrained KP hierarchy II

A constrained KP hierarchy is discussed that was recently suggested by Aratynet al. and by Bonoraet al. This hierarchy is a restriction of the KP to a submanifold of operators which can be represented as a ratio of two purely differential operators of prescribed orders. Explicit formulas for action of vector fields on these two differential operators are written which gives a new description of the hierarchy and provides a new, more constructive proof of compatibility of the constraint with the hierarchy. Also, the Poisson structure of the constrained hierarchy is discussed.
Surface Alloying of Lead as a Step in the Cathodic Generation of the Pb94- in KI and RbBr Liquid Ammonia Solutions

Reduction of lead in liquid ammonia solutions of KI and RbBr at −70 °C was studied using voltammetry as well as potentiostatic and galvanostatic techniques. It was found that the only soluble reduction product was the Zintl ion Pb94-. Transitionally two intermetallic phases were also formed via direct incorporation of the alkali metal into lead, but they eventually dissolved in liquid ammonia. The alkali metal (M)-rich phase had the Pb:M molar ratio around 0.4 for both K and Rb, whereas the ratio for the lead-rich phase was between 0.8:1 and 1: 1 for potassium and around 0.7:1 for rubidium. The alkali metal-rich phase was unstable and easily transformed into the lead-rich phase by the reaction with solid lead. This reaction plays a crucial role both in the alkali metal incorporation and in the solid-phase dissolution reaction. A model mechanism of the lead reduction is presented.
MEMS-Actuated Carbon Fiber Microelectrode for Neural Recording

Microwire and microelectrode arrays used for cortical neural recording typically consist of tens to hundreds of recording sites, but often only a fraction of these sites are in close enough proximity to firing neurons to record single-unit activity. Recent work has demonstrated precise, depth-controllable mechanisms for the insertion of single neural recording electrodes, but these methods are mostly only capable of inserting electrodes which elicit an adverse biological response. We present an electrostatic-based actuator capable of inserting individual carbon fiber microelectrodes which elicit minimal to no adverse biological response. The device is shown to insert a carbon fiber recording electrode into an agar brain phantom and can record an artificial neural signal in saline. This technique provides a platform generalizable to many microwire-style recording electrodes.
Direct synthesis of 3-arylindoles via annulation of aryl hydroxylamines with alkynes

Abstract 3-Arylindoles are produced in moderate to excellent yields from the reaction between aryl hydroxylamines and alkynes catalyzed by 10 mol % iron(II) phthalocyanine [Fe(Pc)]. Terminal and internal alkynes afford 3-aryl substituted indoles exclusively. Electron-donating and -withdrawing groups are tolerated on the aryl hydroxylamine. A few bioactive indoles are synthesized as well as several new indoles using this one-step intermolecular annulation procedure.
Chiral α,β-Dialkoxy- and α-Alkoxy-β-aminostannanes: Preparation and Copper-Mediated Cross-Coupling

Addition of Zn(n-Bu3Sn)2 to prochiral aldehydes affords anti-α,β-dialkoxy- and anti-α-alkoxy-β-aminostannanes in good yield (up to 77%) and excellent diastereoselectivity (up to 98% de). syn-Isomers are accessed from the initial adducts via Mitsunobu inversion/saponification. The corresponding thionocarbamates undergo mild Cu(I)-mediated cross-coupling with a variety of organic halides, inter alia, allylic, cinnamylic, propargylic, and acetylenic, with retention of configuration.
Preparation of Substituted Benzimidazoles and Imidazopyridines Using 2,2,2-Trichloroethyl Imidates

The preparation of benzimidazoles and imidazopyridines has been achieved under mild conditions using 2,2,2-trichloroethyl imidates as the acylating agents. The reactions proceed smoothly in isopropyl alcohol at 70 °C. In cases where the acylation was rapid but the cyclization proceeded slowly, addition of sodium acetate proved to be beneficial. For substrates with poor nucleophilicity, modification of the solvent to the more inert tert-amyl alcohol, which can also achieve higher temperature, allowed for superior reactions.
A convenient method for the synthesis of electron-rich phosphonates

Very electron-rich benzylic-type phosphonates can be prepared by treating the corresponding alcohols in triethyl phosphite with one equivalent of iodine at an appropriate temperature in a general one-pot process.
Pelleted-hay alfalfa feed increases sheep wether weight gain and rumen bacterial richness over loose-hay alfalfa feed.

Diet composed of smaller particles can improve feed intake, digestibility, and animal growth or health, but in ruminant species can reduce rumination and buffering–the loss of which may inhibit fermentation and digestibility. However, the explicit effect of particle size on the rumen microbiota remains untested, despite their crucial role in digestion. We evaluated the effects of reduced particle size on rumen microbiota by feeding long-stem (loose) alfalfa hay compared to a ground and pelleted version of the same alfalfa in yearling sheep wethers during a two-week experimental period. In situ digestibility of the pelleted diet was greater at 48 h compared with loose hay; however, distribution of residual fecal particle sizes in sheep did not differ between the dietary treatments at any time point (day 7 or 14). Both average daily gain and feed efficiency were greater for the wethers consuming the pelleted diet. Observed bacterial richness was very low at the end of the adaptation period and increased over the course of the study, suggesting the rumen bacterial community was still in flux after two weeks of adaptation. The pelleted-hay diet group had a greater increase in bacterial richness, including common fibrolytic rumen inhabitants. The pelleted diet was positively associated with several Succiniclasticum, a Prevotella, and uncultured taxa in the Ruminococcaceae and Rickenellaceae families and Bacteroidales order. Pelleting an alfalfa hay diet for sheep does shift the rumen microbiome, though the interplay of diet particle size, retention and gastrointestinal transit time, microbial fermentative and hydrolytic activity, and host growth or health is still largely unexplored.
FLOW INJECTION CHEMILUMINESCENCE-BASED CHEMICAL SENSORS

ABSTRACT In recent years, the design of chemiluminescence flow injection sensors with immobilized and solid-state reagents has been one of the most active areas in chemiluminescence analysis. In these systems, analytes are detected by the chemiluminescence reactions either with the immobilized reagents directly or with the dissolved reagents which are released from the immobilized substrates or the solid-state forms by some appropriate eluents or are electrogenerated on line by the electrodes. This review discusses recent advances in these fields. The main advantages of the chemiluminescence flow injection sensors are described in comparison with the conventional chemiluminescence flow systems.
Streaming small-footprint keyword spotting using sequence-to-sequence models

We develop streaming keyword spotting systems using a recurrent neural network transducer (RNN-T) model: an all-neural, end-to-end trained, sequence-to-sequence model which jointly learns acoustic and language model components. Our models are trained to predict either phonemes or graphemes as subword units, thus allowing us to detect arbitrary keyword phrases, without any out-of-vocabulary words. In order to adapt the models to the requirements of keyword spotting, we propose a novel technique which biases the RNN-T system towards a specific keyword of interest. Our systems are compared against a strong sequence-trained, connectionist temporal classification (CTC) based “keyword-filler” baseline, which is augmented with a separate phoneme language model. Overall, our RNN-T system with the proposed biasing technique significantly improves performance over the baseline system.
Every binary code can be realized by convex sets

Abstract Much work has been done to identify which binary codes can be represented by collections of open convex or closed convex sets. While not all binary codes can be realized by such sets, here we prove that every binary code can be realized by convex sets when there is no restriction on whether the sets are all open or closed. We achieve this by constructing a convex realization for an arbitrary code with k nonempty codewords in R k − 1 . This result justifies the usual restriction of the definition of convex neural codes to include only those that can be realized by receptive fields that are all either open convex or closed convex. We also show that the dimension of our construction cannot in general be lowered.
Kazhdan-Lusztig polynomials of thagomizer matroids

We introduce thagomizer matroids and compute the Kazhdan-Lusztig polynomial of a rank $n+1$ thagomizer matroid by showing that the coefficient of $t^k$ is equal to the number of Dyck paths of semilength $n$ with $k$ long ascents. We also give a conjecture for the $S_n$-equivariant Kazhdan-Lusztig polynomial of a thagomizer matroid.
Linear Non-Gaussian Component Analysis Via Maximum Likelihood

Independent component analysis (ICA) is popular in many applications, including cognitive neuroscience and signal processing. Due to computational constraints, principal component analysis (PCA) is...
A note about the uniform distribution on the intersection of a simplex and a sphere

Uniform probability distributions on lp balls and spheres have been studied extensively and are known to behave like product measures in high dimensions. In this note we consider the uniform distribution on the intersection of a simplex and a sphere. Certain new and interesting features, such as phase transitions and localization phenomena emerge.