cssi/SciSciGPT-SciSciNet huggingface dataset:
Small computers in data networks

Small computers, costing between, say $10,000 and $50,000 each, are rapidly proving to be very important elements in data communications networks. The value of these machines lies in their high speed data manipulation capability rather than in their computing power; in fact, the direct arithmetic capability rarely exceeds simple binary addition and subtraction.
Randomized Benchmarking of Quantum Gates

A key requirement for scalable quantum computing is that elementary quantum gates can be implemented with sufficiently low error. One method for determining the error behavior of a gate implementation is to perform process tomography. However, standard process tomography is limited by errors in state preparation, measurement and one-qubit gates. It suffers from inefficient scaling with number of qubits and does not detect adverse error-compounding when gates are composed in long sequences. An additional problem is due to the fact that desirable error probabilities for scalable quantum computing are of the order of 0.0001 or lower. Experimentally proving such low errors is challenging. We describe a randomized benchmarking method that yields estimates of the computationally relevant errors without relying on accurate state preparation and measurement. Since it involves long sequences of randomly chosen gates, it also verifies that error behavior is stable when used in long computations. We implemented randomized benchmarking on trapped atomic ion qubits, establishing a one-qubit error probability per randomized $\ensuremath{\pi}/2$ pulse of 0.00482(17) in a particular experiment. We expect this error probability to be readily improved with straightforward technical modifications.
Algorithms for Dynamic Spectrum Access With Learning for Cognitive Radio

We study the problem of dynamic spectrum sensing and access in cognitive radio systems as a partially observed Markov decision process (POMDP). A group of cognitive users cooperatively tries to exploit vacancies in primary (licensed) channels whose occupancies follow a Markovian evolution. We first consider the scenario where the cognitive users have perfect knowledge of the distribution of the signals they receive from the primary users. For this problem, we obtain a greedy channel selection and access policy that maximizes the instantaneous reward, while satisfying a constraint on the probability of interfering with licensed transmissions. We also derive an analytical universal upper bound on the performance of the optimal policy. Through simulation, we show that our scheme achieves good performance relative to the upper bound and improved performance relative to an existing scheme. We then consider the more practical scenario where the exact distribution of the signal from the primary is unknown. We assume a parametric model for the distribution and develop an algorithm that can learn the true distribution, still guaranteeing the constraint on the interference probability. We show that this algorithm outperforms the naive design that assumes a worst case value for the parameter. We also provide a proof for the convergence of the learning algorithm.
Electrospun carbon nanofiber webs with controlled density of states for sensor applications.

1 DOI: 10.1002/adma.((please add manuscript number)) Electrospun Carbon Nanofiber Webs with Controlled Density of States for Sensor Applications By Xianwen Mao, Fritz Simeon, Gregory C. Rutledge* and T. Alan Hatton* [*] Prof. T. Alan Hatton, Prof. Gregory C. Rutledge, Xianwen Mao, Dr. Fritz Simeon. Department of Chemical Engineering, Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge Massachusetts, 02139, USA E-mail: tahatton@mit.edu, rutledge@mit.edu
Economic evaluation of grid-connected fuel-cell systems

An assessment of the economic benefits of using fuel cells is presented. A calculation of the cost of electricity generated from a fuel-cell installation, and a determination of the amount of profit that might result from an installation is given. A break even and sensitivity analysis is also conducted to determine what goals need to be achieved to make fuel cells competitive with conventional power generation sources. The study was performed using a graphical user interface programmed in MATLAB.
1,4-Benzenedicarboxylate derivatives as links in the design of paddle-wheel units and metal–organic frameworks

The square grid structure of MOF-2, constructed from paddle-wheel units of Zn(II) and 1,4-benzenedicarboxylate (BDC) links, persists for 2-amino-1,4-benzenedicarboxylate (ABDC) links but not for the sterically demanding 2,3,5,6-tetramethyl-1,4-benzenedicarboxylate (TBDC); the dihedral angle between planes of the benzene and carboxylate groups play a determining role in the formation of the paddle-wheel motif.
An organic white light-emitting dye: very small molecular architecture displays panchromatic emission

The synthesis and photophysical characterization of a new white-light fluorophore is described. The optimization of excitation wavelengths allows the naphthalimide (NI) dyes to display blue, green or white light emission depending on the excitation wavelength.
Optimal training for MIMO frequency-selective fading channels

High data rates give rise to frequency-selective propagation effects. Space-time multiplexing and/or coding offer attractive means of combating fading and boosting capacity of multi-antenna communications. As the number of antennas increases, channel estimation becomes challenging because the number of unknowns increases, and the power is split at the transmitter. Optimal training sequences have been designed for flat-fading multi-antenna systems or for frequency-selective single transmit antenna systems. We design a low-complexity optimal training scheme for block transmissions over frequency-selective channels with multiple antennas. The optimality in designing our training schemes consists of maximizing a lower bound on the ergodic (average) capacity that is shown to be equivalent to minimizing the mean square error of the linear channel estimator. Simulation results confirm our theoretical analysis that applies to both single- and multicarrier transmissions.
Light-to-Mass Variations with Environment

Large and well-defined variations exist between the distribution of mass and the light of stars on extragalactic scales. Mass concentrations in the range 1012-1013 M☉ manifest the most light per unit mass. Group halos in this range are typically the hosts of spiral and irregular galaxies with ongoing star formation. On average M/LB ~ 90 M☉/L☉ in these groups . More massive halos have less light per unit mass. Within a given mass range, halos that are dynamically old as measured by crossing times and galaxy morphologies have distinctly less light per unit mass. At the other end of the mass spectrum, below 1012 M☉, there is a cutoff in the manifestation of light. Group halos in the range 1011-1012 M☉ can host dwarf galaxies but with such low luminosities that M/LB values can range from several hundred to several thousand. It is suspected that there must be completely dark halos at lower masses. Given the form of the halo mass function, the low relative luminosities of the high-mass halos have the greatest cosmological implications. Of order half the clustered mass may reside in halos with greater than 1014 M☉. By contrast, only 5%-10% of clustered mass would lie in entities with less than 1012 M☉.
Total synthesis of aspidophytine

A total synthesis of aspidophytine was accomplished by employing a newly developed strategy for the enantiospecific syntheses of aspidosperma alkaloids. The key steps involve a novel ketene-lactonization reaction of a chiral vinyl sulfoxide (Marino annulation reaction) to set up the chiral quaternary carbon center, and a tandem Michael addition-alkylation reaction sequence to form the polycyclic core structure.
Low-Voltage PWM inverter-fed motor insulation issues

The topic of how low-voltage insulated-gate-bipolartransistor (IGBT)-based pulsewidth modulation (PWM) inverters create additional insulation stress through voltage reflections (due to high dV/dt) has been documented for several years. First, this paper explains and summarizes the basic causes and effects of the high dV/dt environment. Second, the methodologies of various approaches to solutions are critically reviewed. Finally, standards (such as NEMA MG1, parts 30, 31) (NEMA Standards Publication MG 1, 2003) have attempted to partially address this issue. However, there are still some areas that require important clarification. This paper makes the case for what can be done to achieve the needed clarity. Testing of motor insulation systems to verify compliance with the proposed requirements is also covered.
Preparation of 1,1,2-trifluoro-2-trimethylsilylethylene

Abstract 1,1,2-Trifluoro-2-trimethylsilylethylene can be readily prepared via the Cu(I)Br catalyzed silylation of the 1,1,2-trifluoroethenylzinc reagent with Me 3 SiCl. The reaction is easily scaled-up, isolation of the trifluorovinylsilane is facile, and the procedure can be readily adapted to other trialkyl halosilanes.
Benzothiazines in synthesis. Formal syntheses of (+)-curcumene and (+)-curcuphenol

A benzothiazine readily available in enantiomerically pure form via a stereoselective, intramolecular Michael addition reaction could be converted to a precursor to (+)-curcuphenol and to (+)-curcumene.
Rich RNA Structure Landscapes Revealed by Mutate-and-Map Analysis

Landscapes exhibiting multiple secondary structures arise in natural RNA molecules that modulate gene expression, protein synthesis, and viral. We report herein that high-throughput chemical experiments can isolate an RNA’s multiple alternative secondary structures as they are stabilized by systematic mutagenesis (mutate-and-map, M2) and that a computational algorithm, REEFFIT, enables unbiased reconstruction of these states’ structures and populations. In an in silico benchmark on non-coding RNAs with complex landscapes, M2-REEFFIT recovers 95% of RNA helices present with at least 25% population while maintaining a low false discovery rate (10%) and conservative error estimates. In experimental benchmarks, M2-REEFFIT recovers the structure landscapes of a 35-nt MedLoop hairpin, a 110-nt 16S rRNA four-way junction with an excited state, a 25-nt bistable hairpin, and a 112-nt three-state adenine riboswitch with its expression platform, molecules whose characterization previously required expert mutational analysis and specialized NMR or chemical mapping experiments. With this validation, M2-REEFFIT enabled tests of whether artificial RNA sequences might exhibit complex landscapes in the absence of explicit design. An artificial flavin mononucleotide riboswitch and a randomly generated RNA sequence are found to interconvert between three or more states, including structures for which there was no design, but that could be stabilized through mutations. These results highlight the likely pervasiveness of rich landscapes with multiple secondary structures in both natural and artificial RNAs and demonstrate an automated chemical/computational route for their empirical characterization.
Goals and processes: the Arab world and the transitional justice impact literature

This article uses the cases of Iraq, Algeria and Morocco to highlight some of the limitations of the transitional justice impact literature, which often assumes direct, linear relationships exist between transitional justice mechanisms and a variety of outcomes. In several respects, these countries' experiences differ from the expectations of recent studies. Although not equally flawed, in each case, transitional justice has been used to legitimise the current regime and, particularly in Iraq, to exact revenge against the ancien regime. Simultaneously, the demands of victims have largely been given short shrift. Viewing transitional justice in these countries as a process, as has been suggested, may be useful theoretically, but does not necessarily give more reason for optimism. The article offers provisional conclusions regarding these cases and discusses what lessons they provide for the impact literature and for the post-2011 Middle East. In particular, retributive measures appear to have particularly ...
Do Sports Crowd Out Books? The Impact of Intercollegiate Athletic Participation on Grades

We investigate the influence of intercollegiate athletic participation on grades using data from the U.S. Naval Academy. Athletic participation is an endogenous decision with respect to educational...
Three Myths about Time Reversal in Quantum Theory

Many have suggested that the transformation standardly referred to as ‘time reversal’ in quantum theory is not deserving of the name. I argue on the contrary that the standard definition is perfectly appropriate and is indeed forced by basic considerations about the nature of time in the quantum formalism.
Correlation of PROMIS Physical Function and Pain CAT Instruments With Oswestry Disability Index and Neck Disability Index in Spine Patients.

Study design A prospective and retrospective cross-sectional cohort analysis. Objective The aim of this study was to show that Patient-Reported Outcomes Measurement Information System (PROMIS) computer adaptive testing (CAT) assessments for physical function and pain interference can be efficiently collected in a standard office visit and to evaluate these scores with scores from previously validated Oswestry Disability Index (ODI) and Neck Disability Index (NDI) providing evidence of convergent validity for use in patients with spine pathology. Summary of background data Spinal surgery outcomes are highly variable, and substantial debate continues regarding the role and value of spine surgery. The routine collection of patient-based outcomes instruments in spine surgery patients may inform this debate. Traditionally, the inefficiency associated with collecting standard validated instruments has been a barrier to routine use in outpatient clinics. We utilized several CAT instruments available through PROMIS and correlated these with the results obtained using "gold standard" legacy outcomes measurement instruments. Methods All measurements were collected at a routine clinical visit. The ODI and the NDI assessments were used as "gold standard" comparisons for patient-reported outcomes. Results PROMIS CAT instruments required 4.5 ± 1.8 questions and took 35 ± 16 seconds to complete, compared with ODI/NDI requiring 10 questions and taking 188 ± 85 seconds when administered electronically. Linear regression analysis of retrospective scores involving a primary back complaint revealed moderate to strong correlations between ODI and PROMIS physical function with r values ranging from 0.5846 to 0.8907 depending on the specific assessment and patient subsets examined. Conclusion Routine collection of physical function outcome measures in clinical practice offers the ability to inform and improve patient care. We have shown that several PROMIS CAT instruments can be efficiently administered during routine clinical visits. The moderate to strong correlations found validate the utility of computer adaptive testing when compared with the gold standard "static" legacy assessments. Level of evidence 4.
Mapping and correcting the influence of gaze position on pupil size measurements

Pupil size is correlated with a wide variety of important cognitive variables and is increasingly being used by cognitive scientists. Pupil data can be recorded inexpensively and non-invasively by many commonly used video-based eye-tracking cameras. Despite the relative ease of data collection and increasing prevalence of pupil data in the cognitive literature, researchers often underestimate the methodological challenges associated with controlling for confounds that can result in misinterpretation of their data. One serious confound that is often not properly controlled is pupil foreshortening error (PFE)—the foreshortening of the pupil image as the eye rotates away from the camera. Here we systematically map PFE using an artificial eye model and then apply a geometric model correction. Three artificial eyes with different fixed pupil sizes were used to systematically measure changes in pupil size as a function of gaze position with a desktop EyeLink 1000 tracker. A grid-based map of pupil measurements was recorded with each artificial eye across three experimental layouts of the eye-tracking camera and display. Large, systematic deviations in pupil size were observed across all nine maps. The measured PFE was corrected by a geometric model that expressed the foreshortening of the pupil area as a function of the cosine of the angle between the eye-to-camera axis and the eye-to-stimulus axis. The model reduced the root mean squared error of pupil measurements by 82.5 % when the model parameters were pre-set to the physical layout dimensions, and by 97.5 % when they were optimized to fit the empirical error surface.
Can irrational investors survive in the long run? The role of generational type transmission ☆

This paper considers whether expected utility maximizers who have incorrect beliefs can survive as controllers of a significant portion of market wealth in the long run. Unlike infinitely-lived agent models, where this is not the case, we consider a model with successive generations of investors. Each generation inherits wealth and investor type from the previous generation. We show that if rational parents produce only rational children, and irrational parents always produce only irrational children, then the results from the infinitely-lived setup carry through. However, if parents of one type can produce even a small fraction of children of the other type, then irrational investors will always control a non-vanishing portion of total wealth. Hence, understanding the exact nature of the transmission of incorrect beliefs is key to understanding long-run market prices.
Eating Heavily: Men Eat More in the Company of Women

Sexual selection has been commonly considered by evolutionary psychologists interested in eating disorders among women; however, comparable attention has not been paid to problematic eating by men. We present the results of a field study through which we find that men eat more food when sharing a meal with women than with men. Notably, men appear to eat larger quantities of both unhealthy (pizza) and healthy (salad) food when in the company of women. More specifically, men eating with women ate 93% more pizza (1.44 more slices) and 86% more salad. Additionally, while women do not eat significantly differently as a function of the sex of their dining partners, women eating with men tended to estimate themselves to have eaten more and reported feeling like they were rushed and overate. In addition to expanding upon previous research concerning women’s eating behaviors, our findings concerning male overconsumption in the presence of women appear to present an example of self-handicap behavior.
Surveys at Cougar Reservoir

An outline is given of surveys made in the Willamette Valley preliminary to the special surveys at Cougar Reservoir and Dam Site. Factors which must be considered in large scale photogrammetric mapping of precipituous high relief areas are presented and how these problems were resolved using projector type stereoplotting equipment.
Development of a cell line based gene classifier to predict therapeutic response of head and neck cancer patients

AACR Annual Meeting-- Apr 12-16, 2008; San Diego, CA 4098 A major goal of cancer biology is the development of assays to predict therapeutic response in solid tumors. We developed a classifier that predicts clinical response to chemotherapy and radiation therapy of squamous cell carcinomas of the head and neck (SCCHN) based on expression profiles of genes in the NFκB signaling pathway. As a starting point we used two SCCHN tumor cell lines (SQ20B and T409) that were both radio- and chemotherapy resistant and two SCCHN tumor cell lines (SCC61 and T167) cells that were sensitive to these treatments. Isolated mRNA was used to test the expression levels of 84 genes involved in NFκB signaling pathway using real time RT PCR. Eighteen genes showed changes in expression of more than 4-fold in radioresistant cells compared to radiosensitive cells (14 up-regulated and 4 down-regulated). The down-regulated genes included NFκB target genes (ICAM1 and CSF2) and an NFκB signaling activator (IL8). The up-regulated genes included regulators of NFκB signaling (TBK1, HTR2B, BIRC2, and TLR6). A multivariate linear regression model was used to identify gene expression patterns that correlated with response, using radiation or chemotherapy-based cell killing as a continuous variable. This process identified eight NFκB dependent genes with expression levels that correlated with resistance to radiation and chemotherapy. These were used to generate a set of classifier rules to distinguish sensitive from resistant cells. The classifier rules were then validated using primary tumor specimens from 22 untreated SCCHN cancer patients. Expression profiling data obtained using RNA isolated from these tumors were stratified using the classifier rules and the response was predicted. The predicted response was then compared to the actual clinical outcome, defined as tumor recurrence after therapy, using data obtained from electronic health records of the patients. The classifier correctly predicted the clinical response in 90% (20 of 22) of the cases. However, using McNemar's statistical method (p-value=0.001) only 31% of the assayed genes showed concordance in expression pattern between the original cell lines and patient samples. In conclusion, we demonstrate that therapeutic response can be predicted based on gene expression profiles. We did this by identifying novel associations between molecules in the NFκB signaling pathway and treatment sensitivity. The classifier rules we developed correctly predicted clinical outcome in a high percentage of patients, which has significant implications for patient therapy. Analysis of more patient samples as well as other pro-survival signaling pathways is needed before these methods are generally used in the clinic.
Learning to Be Thoughtless: Social Norms and Individual Computation

This paper extends the literature on the evolution of norms with an agent-based model capturing a phenomenon that has been essentially ignored, namely that individual thought – or computing – is often inversely related to the strength of a social norm. Once a norm is entrenched, we conform thoughtlessly. In this model, agents learn how to behave (what norm to adopt), but – under a strategy I term Best Reply to Adaptive Sample Evidence – they also learn how much to think about how to behave. How much they are thinking affects how they behave, which – given how others behave – affects how much they think. In short, there is feedback between the social (inter-agent) and internal (intra-agent) dynamics. In addition, we generate the stylized facts regarding the spatio-temporal evolution of norms: local conformity, global diversity, and punctuated equilibria.
Tritium analysis in palladium with an open system analytical procedure

In 45 palladium samples produced by three different manufacturers in various lots and sizes, no evidence of tritium contamination is found. Within the maximum error of the experiments, i.e., {plus minus} 3 decay/min {center dot} ml{sup {minus}1}, the palladium samples give tritium counts identical with the background of 26 decay/min {center dot} ml. In this paper the major factors leading to possible errors in applying this technique are discussed. False high readings may be caused by chemiluminescence, photoluminescence, colored solution, and chemical reactions. But false high readings are not obtained when automatic quench control and other standard precautions are employed. On the other hand, false low readings can result from the escape of dissolved tritium gas. Closed system analytical procedures are, therefore, preferred.
Fifty Ways to Leave a Child Behind Idiosyncrasies and Discrepancies in States’ Implementation of NCLB

The No Child Left Behind (NCLB) Act required states to adopt accountability systems measuring student proficiency on state-administered exams. The federal legislation contained several strict requirements for NCLB implementation, such as escalating student proficiency targets that reach 100% proficiency by 2014. But it also gave states considerable flexibility to interpret and implement components of NCLB. Using a data set we constructed, this paper is the first national study examining which schools failed during the early years of NCLB and which performance targets they failed to meet. We explore how states’ NCLB implementation decisions were related to their schools’ failure rates, which ranged from less than 1% to more than 80% across states. Wide cross-state variation in failure rates resulted from how states’ decisions interacted with each other and with school characteristics, like enrollment size, grade span, and ethnic diversity. Subtle differences in policy implementation may cause dramatic diff...
Catalytic insertion of aldehydes into dihalonitroacetophenones via sequential bond scission-aldol reaction-acyl transfer

A catalytic process that provides dihalogenated nitro alcohols in up to 99% yield and with 100% atom economy is described. In situ cleavage of dihalonitroacetophenones affords nitronates that undergo Lewis acid catalyzed addition to aldehydes. Final benzoylation renders the sequence irreversible and regenerates the bond scission and acyl transfer agent.
Assessing Revenue Authority Performance in Developing Countries: A Synthetic Control Approach

ABSTRACTIn many developing countries, comprehensive reforms have been undertaken in tax administration during recent years and the implementation of semiautonomous revenue authorities (SARAs) constitutes one of their most visible expressions. To date, no comprehensive assessment has been undertaken to investigate how successful these SARAs have been in improving revenue collection in these countries. Therefore, this article attempts to fill this gap by assessing revenue collection trends in 20 developing countries after the SARA has been implemented. Using the synthetic control method, we show that in most countries, the implementation of a SARA did not significantly improve government revenues.
Enhancement of Two-Photon Absorption in Quantum Wells for Extremely Nondegenerate Photon Pairs

We recently demonstrated orders of magnitude enhancement of two-photon absorption (2PA) in direct gap semiconductors due to intermediate state resonance enhancement for photons of very different energies. It can be expected that further enhancement of nondegenerate 2PA will be observed in quantum wells (QWs), since the intraband matrix elements do not vanish near the band center, as they do in the bulk, and the density of states in QWs is larger near the band edge. Here, we present a perturbation-theory-based theoretical description of nondegenerate 2PA in semiconductor QWs, where both the frequency and the polarization of two incident waves can vary independently. Analytical expressions for all possible permutations of frequencies and polarizations have been obtained, and the results are compared with the degenerate 2PA in QWs along with the degenerate 2PA and the nondegenerate 2PA in bulk semiconductors. We show that using QWs in place of bulk semiconductors with both the beams in the transverse magnetic-polarized mode leads to an additional order of magnitude increase in the nondegenerate 2PA. Explicit calculations for GaAs QWs are presented.
Quality Improvement of Subgrade Through Intelligent Compaction

Proper quality control and quality improvement strategies during compaction can improve the quality of the subgrade and minimize premature failures of asphalt pavements. This paper discusses the use of the Intelligent Compaction Analyzer (ICA), which was developed at the University of Oklahoma, in quality control and quality improvement during compaction of stabilized subgrade. Six case studies were conducted to demonstrate the ability of the ICA in monitoring subgrade density and subgrade modulus (known as ICA modulus) in real time. The ICA modulus correlated reasonably with the subgrade modulus backcalculated from the falling weight deflectometer data (R2 = .63), fairly with the dynamic cone penetrometer test results (R2 = .50), and excellently with the in situ subgrade resilient modulus (R2 = .72 to .97). The subgrade modulus in undercompacted areas could be increased by more than 50% by applying additional roller passes.
Approximation Algorithms for Polynomial-Expansion and Low-Density Graphs

We investigate the family of intersection graphs of low density objects in low dimensional Euclidean space. This family is quite general, and includes planar graphs. This family of graphs has some interesting properties, and in particular, it is a subset of the family of graphs that have polynomial expansion.
A Pilot Study of Neonatologists' Decision-Making Roles in Delivery Room Resuscitation Counseling for Periviable Births.

ABSTRACTBackground: Relatively little is known about neonatologists' roles in helping families navigate the difficult decision to attempt or withhold resuscitation for a neonate delivering at the threshold of viability. Therefore, we aimed to describe the “decision-making role” of neonatologists in simulated periviable counseling sessions. Methods: We conducted a qualitative content analysis of audio-recorded simulation encounters and postencounter debriefing interviews collected as part of a single-center simulation study of neonatologists' resuscitation counseling practices in the face of ruptured membranes at 23 weeks gestation. We trained standardized patients to request a recommendation if the physician presented multiple treatment options. We coded each encounter for communication behaviors, applying an adapted, previously developed coding scheme to classify physicians into four decision-making roles (informative, facilitative, collaborative, or directive). We also coded postsimulation debriefing in...
Holographic conformal blocks from interacting Wilson lines

We present a simple prescription for computing conformal blocks and correlation functions holographically in AdS3 in terms of Wilson lines merging at a bulk vertex. This is shown to reproduce global conformal blocks and heavy-light Virasoro blocks. In the case of higher spin theories the space of vertices is in one-to-one correspondence with the space of $$ {\mathcal{W}}_N $$ conformal blocks, and we show how the latter are obtained by explicit computations.
Data of NODDI diffusion metrics in the brain and computer simulation of hybrid diffusion imaging (HYDI) acquisition scheme

This article provides NODDI diffusion metrics in the brains of 52 healthy participants and computer simulation data to support compatibility of hybrid diffusion imaging (HYDI), "Hybrid diffusion imaging"[1] acquisition scheme in fitting neurite orientation dispersion and density imaging (NODDI) model, "NODDI: practical in vivo neurite orientation dispersion and density imaging of the human brain"[2]. HYDI is an extremely versatile diffusion magnetic resonance imaging (dMRI) technique that enables various analyzes methods using a single diffusion dataset. One of the diffusion data analysis methods is the NODDI computation, which models the brain tissue with three compartments: fast isotropic diffusion (e.g., cerebrospinal fluid), anisotropic hindered diffusion (e.g., extracellular space), and anisotropic restricted diffusion (e.g., intracellular space). The NODDI model produces microstructural metrics in the developing brain, aging brain or human brain with neurologic disorders. The first dataset provided here are the means and standard deviations of NODDI metrics in 48 white matter region-of-interest (ROI) averaging across 52 healthy participants. The second dataset provided here is the computer simulation with initial conditions guided by the first dataset as inputs and gold standard for model fitting. The computer simulation data provide a direct comparison of NODDI indices computed from the HYDI acquisition [1] to the NODDI indices computed from the originally proposed acquisition [2]. These data are related to the accompanying research article "Age Effects and Sex Differences in Human Brain White Matter of Young to Middle-Aged Adults: A DTI, NODDI, and q-Space Study" [3].
Probabilistic response and rare events in Mathieu׳s equation under correlated parametric excitation

Abstract We derive an analytical approximation to the probability distribution function (pdf) for the response of Mathieu׳s equation under parametric excitation by a random process with a spectrum peaked at the main resonant frequency, motivated by the problem of large amplitude ship roll resonance in random seas. The inclusion of random stochastic excitation renders the otherwise straightforward response to a system undergoing intermittent resonances : randomly occurring large amplitude bursts. Intermittent resonance occurs precisely when the random parametric excitation pushes the system into the instability region, causing an extreme magnitude response. As a result, the statistics are characterized by heavy-tails. We apply a recently developed mathematical technique, the probabilistic decomposition-synthesis method, to derive an analytical approximation to the non-Gaussian pdf of the response. We illustrate the validity of this analytical approximation through comparisons with Monte-Carlo simulations that demonstrate our result accurately captures the strong non-Gaussianinty of the response.
Triallelic Population Genomics for Inferring Correlated Fitness Effects of Same Site Nonsynonymous Mutations

The distribution of mutational effects on fitness is central to evolutionary genetics. Typical univariate distributions, however, cannot model the effects of multiple mutations at the same site, so we introduce a model in which mutations at the same site have correlated fitness effects. To infer the strength of that correlation, we developed a diffusion approximation to the triallelic frequency spectrum, which we applied to data from Drosophila melanogaster . We found a moderate positive correlation between the fitness effects of nonsynonymous mutations at the same codon, suggesting that both mutation identity and location are important for determining fitness effects in proteins. We validated our approach by comparing it to biochemical mutational scanning experiments, finding strong quantitative agreement, even between different organisms. We also found that the correlation of mutational fitness effects was not affected by protein solvent exposure or structural disorder. Together, our results suggest that the correlation of fitness effects at the same site is a previously overlooked yet fundamental property of protein evolution.
Thermal oxidation of mono-unsaturated short chain fatty acids: II. Methyl hexenoate, hexenoic acid, and octenoic acid

Samples of methyl 3-hexenoate, methyl 2-hexenoate, 3-hexenoic, and 3-octenoic acid were oxidized and their decomposition products analyzed. Certain aldehydes, ketones, shorter chain acids or esters, hydroxy-derivatives, and dimers were found among the oxidation products of all four substrates. Epoxyesters and 4-oxo-derivatives were major products from the esters but absent in the case of the acids. 3-heptene and 5-undecene were unique for 3-hexenoic and 3-octenoic acids, respectively. Reaction mechanisms are proposed for the formation of these products.
Expedient Synthesis of Chiral Homoallylamines via N,O-Acetal TMS Ethers and Its Application

A highly stereoselective and efficient method for the synthesis of optically active homoallylamines was developed. Key features of the method include (1) the utilization of naphthylethylamine as both an excellent chiral auxiliary and the amine source, (2) the 1,3-chiral induction of the N-acyliminium ion with high stereoselectivity and high yield, and (3) facile auxiliary removal under mild conditions to liberate N-Cbz-protected homoallylamines. In addition, the total synthesis of the proposed novel tripeptide containing a β-amino acid has been achieved by applying this method.
Childhood outcomes after hypothermia for neonatal encephalopathy

Background We previously reported early results of a randomized trial of whole-body hypothermia for neonatal hypoxic–ischemic encephalopathy showing a significant reduction in the rate of death or moderate or severe disability at 18 to 22 months of age. Long-term outcomes are now available. Methods In the original trial, we assigned infants with moderate or severe encephalopathy to usual care (the control group) or whole-body cooling to an esophageal temperature of 33.5°C for 72 hours, followed by slow rewarming (the hypothermia group). We evaluated cognitive, attention and executive, and visuospatial function; neurologic outcomes; and physical and psychosocial health among participants at 6 to 7 years of age. The primary outcome of the present analyses was death or an IQ score below 70. Results Of the 208 trial participants, primary outcome data were available for 190. Of the 97 children in the hypothermia group and the 93 children in the control group, death or an IQ score below 70 occurred in 46 (47%) ...
Domestic Violence, Intrahousehold Bargaining and Child Health Development in Ghana

I explore a unique exogenous instrument to examine how the intra-familial position of women influence health outcomes of their children using micro data from Ghana Demographic and Health Survey, 2008. Using the 2 SLS-IV estimation technique, I build a model of household bargaining and child health development with perceptions of women regarding wife-beating and marital rape in the existence of domestic violence laws, in Ghana. Even though the initial OLS estimates suggest that women’s participation in decisions regarding purchases of household consumption goods help to improve child health outcomes, the IV estimates reveal that the presence of endogeneity underestimates the impact of women’s bargaining power on child health outcomes. Our Hausman test for endogeneity also confirms that health development of children is mediated through domestic violence laws, which protect women from physical and sexual abuse in the household.
A new environment-sensitive fluorescent amino acid for Fmoc-based solid phase peptide synthesis

A new 4-(N,N-dimethylamino) phthalimide-based environment-sensitive fluorescent building block for solid phase peptide synthesis 3, has been synthesized and incorporated into peptides. Peptides incorporating this residue show great potential for biological applications in sensing protein/protein interactions.
Stability Analysis of Non-Foster-Circuit-Loaded Artificial Magnetic Conductors

The mushroom-type artificial magnetic conductor (AMC), originally presented by Sievenpiper et al., (IEEE Trans. Microwave Theory Tech., 47, pp. 2059–2074, 1999) has found numerous applications, e.g., underneath horizontally polarized antennas, between planar antennas for reducing the coupling between them, for reducing the E-plane edge diffraction from finite ground planes, and for suppression of noise in multilayer circuits. Recently the AMC loaded with negative-inductor non-Foster circuits (NFCs) was investigated for substantial reduction of the resonant frequency and for increasing its bandwidth (Gregoire et al., IEEE Antennas and Wireless Prop. Lett., 10, pp. 1586–1589, 2011). The objective of this work is to investigate the stability of the active circuit loaded AMC (AAMC).
Generating potassium abundance variations in the Solar Nebula

An intriguing aspect of chondritic meteorites is that they are complementary: while their separate components have wildly varying abundances, bulk chondrites have nearly solar composition. This implies that the nearly-solar reservoirs in which chondrites were born were in turn assembled from sub-reservoirs of differing compositions that birthed the different components. We focus on explaining the potassium abundance variations between chondrules even within a single chondrite, while maintaining the observed CI $^{41}$K to $^{39}$K ratios. This requires physically separating potassium and chondrules while the temperature is high enough for K to be in the gas phase. We examine several mechanisms which could drive the dust through gas and show that to do so locally would have required long (sub-orbital to many orbits) time scales; with shortest potassium depletion time scales occurring in a scenario where chondrules formed high above the midplane and settled out of the evaporated potassium. While orbital time scales are at odds with laboratory chondrule cooling rate estimates, any other model for the origin for the potassium abundance variation has to wrestle with the severe logistical difficulty of generating a plethora of correlated reservoirs which varied strongly in their potassium abundances, but not in their potassium isotope ratios.
Characteristics and Limitations of Photographic Films Used in Subtraction Radiography

An investigation was made to evaluate currently used subtraction radiography techniques. The first order subtraction technique was found to be adequate for conventional clinical use. However when using fine-grain high contrast films for the originals, the second order technique gave a more accurate subtraction image. The limiting factor in the sensitivity of the radiographic subtraction technique for detecting small contrast changes over an area of about 2 cm in diameter was found to be film noise and not quantum statistics. Extra-fine-grain films were compared with conventionally used films. While these extra-fine-grain films gave slightly better results, they also required x-ray exposures which would be too high for routine clinical use.
The subjective well-being of group leaders as explained by the quality of leader–member exchange

Abstract Although a great deal of research explores the ramifications of leader–member exchange (LMX) quality for the well-being of followers, leader well-being is largely overlooked. To address this gap, we investigate whether leaders' well-being, in the form of positive affect and job stress, can be explained by LMX quality at the group level of analysis. We analyzed data from 1297 group members within 162 groups matched with individual leaders. Results showed that leaders' positive affect and job stress were uniquely explained by LMX differentiation (group-member data), even after several relevant variables, including fundamental leader attitudes and average LMX (group-member data), were taken into account. A subsequent analytical step revealed a significant interaction between average LMX and LMX differentiation for leader job stress, yet not for leader positive affect. Specifically, the positive relationship between LMX differentiation and leader job stress was discovered to be greater at low average LMX than at high average LMX. Overall, the findings highlight leaders' well-being as a promising avenue for future LMX research and a group level of analysis as useful in studying social exchange.
THR WITH THE A “LATERAL FLARE” STEM: MINIMUM 15 YEAR PROSPECTIVE FOLLOW UP IN 62 HIPS.

This is a minimum 15 year follow up of a cohort of 58 patients (30 men and 28 women) who underwent 62 non-cemented THR between 1998–2000 (54 unilateral, 4 bilateral), in whom an off-the-shelf “lateral flare” femoral component was implanted. These surgeries were performed by a single surgeon and have been followed continuously by that same surgeon. The mean age at the time of surgery was 60.4 yrs (52–74). There were no exclusions for osteoporosis or type “C” femoral geometry. Although some patients have deceased during these 15 years, there have been no stem failures, revisions or impending stem revisions at the time of follow up or at the time of death in those who have passed. Two patients have undergone revision of their acetabular liner for poly wear. There have been no complaints of thigh pain; and like the results seen in other series employing this stem design, there has been no evidence of bone loss due to stress shielding or subsidence of the femoral component in any of these patients. This mid-term follow up re-affirms the dynamic tension band model of hip biomechanics, upon which the “lateral flare” design is predicated. This model predicts that the proximal lateral femur can experience compression during the gait cycle and as such can be utilized as an additional base of support upon which the femoral component can rest. Rather than relying upon a traditional “press fit” technique to achieve initial implant stability, a technique which is highly dependent upon femoral geometry, bone quality and may risk fracture on implant seating, the “lateral flare” design permits a gentler, safer and more physiologic means of achieving initial implant stability necessary for osseous integration to occur. This alterantive terchnique has been termed a “rest fit”.
Application of Surface Coils to MR Anatomy of the Larynx

The magnetic resonance (MR) scans of 10 patients with normal larynges were compared with cryomicrosections of two injected cadaver specimens. The MR images were obtained with a solenoid surface coil and high-resolution techinque that provided images 4 mm thick displayed on a 256 × 256 matrix. The improved signal-to-noise ratio of the surface coil allowed a detailed study of normal anatomy in the axial, coronal, and sagittal planes.
An Algorithm for stable Microtubule Curvature Conformation

Self-assembly is a ubiquitous, naturally occurring, robust process in many living organisms. Microtubule, a self-organization system assembles itself into functional units by attaching to cellular structures. Modeling microtubule self-organization is of interest as microtubule forms a network of protein filaments that is critical to many processes in eukaryotic cells. In this paper, we developed a modeling algorithm starting from alpha and beta tubulins as basic building block in the self-organization of microtubule. The developed algorithm and the necessary steps are described in detail. The preliminary results obtained from the model demonstrate that a stable self-organization conformation is possible for a microtubule.
Functional analysis of the N-terminal basic motif of a eukaryotic satellite RNA virus capsid protein in replication and packaging

Efficient replication and assembly of virus particles are integral to the establishment of infection. In addition to the primary role of the capsid protein (CP) in encapsidating the RNA progeny, experimental evidence on positive sense single-stranded RNA viruses suggests that the CP also regulates RNA synthesis. Here, we demonstrate that replication of Satellite tobacco mosaic virus (STMV) is controlled by the cooperative interaction between STMV CP and the helper virus (HV) Tobacco mosaic virus (TMV) replicase. We identified that the STMV CP-HV replicase interaction requires a positively charged residue at the third position (3R) in the N-terminal 13 amino acid (aa) motif. Far-Northwestern blotting showed that STMV CP promotes binding between HV-replicase and STMV RNA. An STMV CP variant having an arginine to alanine substitution at position 3 in the N-terminal 13aa motif abolished replicase-CP binding. The N-terminal 13aa motif of the CP bearing alanine substitutions for positively charged residues located at positions 5, 7, 10 and 11 are defective in packaging full-length STMV, but can package a truncated STMV RNA lacking the 3′ terminal 150 nt region. These findings provide insights into the mechanism underlying the regulation of STMV replication and packaging.