cssi/SciSciGPT-SciSciNet huggingface dataset:
A high-order integral algorithm for highly singular PDE solutions in Lipschitz domains

We present a new algorithm, based on integral equation formulations, for the solution of constant-coefficient elliptic partial differential equations (PDE) in closed two-dimensional domains with non-smooth boundaries; we focus on cases in which the integral-equation solutions as well as physically meaningful quantities (such as, stresses, electric/magnetic fields, etc.) tend to infinity at singular boundary points (corners). While, for simplicity, we restrict our discussion to integral equations associated with the Neumann problem for the Laplace equation, the proposed methodology applies to integral equations arising from other types of PDEs, including the Helmholtz, Maxwell, and linear elasticity equations. Our numerical results demonstrate excellent convergence as discretizations are refined, even around singular points at which solutions tend to infinity. We demonstrate the efficacy of this algorithm through applications to solution of Neumann problems for the Laplace operator over a variety of domains—including domains containing extremely sharp concave and convex corners, with angles as small as π/100 and as large as 199π/100.
Uncovering Specific Electrostatic Interactions in the Denatured States of Proteins

The stability and folding of proteins are modulated by energetically significant interactions in the denatured state that is in equilibrium with the native state. These interactions remain largely invisible to current experimental techniques, however, due to the sparse population and conformational heterogeneity of the denatured-state ensemble under folding conditions. Molecular dynamics simulations using physics-based force fields can in principle offer atomistic details of the denatured state. However, practical applications are plagued with the lack of rigorous means to validate microscopic information and deficiencies in force fields and solvent models. This study presents a method based on coupled titration and molecular dynamics sampling of the denatured state starting from the extended sequence under native conditions. The resulting denatured-state pKas allow for the prediction of experimental observables such as pH- and mutation-induced stability changes. I show the capability and use of the method by investigating the electrostatic interactions in the denatured states of wild-type and K12M mutant of NTL9 protein. This study shows that the major errors in electrostatics can be identified by validating the titration properties of the fragment peptides derived from the sequence of the intact protein. Consistent with experimental evidence, our simulations show a significantly depressed pKa for Asp8 in the denatured state of wild-type, which is due to a nonnative interaction between Asp8 and Lys12. Interestingly, the simulation also shows a nonnative interaction between Asp8 and Glu48 in the denatured state of the mutant. I believe the presented method is general and can be applied to extract and validate microscopic electrostatics of the entire folding energy landscape.
Modulational instability of quasi-plane-wave optical beams biased in photorefractive crystals

The modulational instability of quasi-plane-wave optical beams in biased photorefractive media is investigated under steady-state conditions. The spatial growth rate of the sideband perturbations is obtained by globally treating the space-charge field. Our analysis indicates that the growth rates depend on the strength of the externally applied electric field and, moreover, on the ratio of the optical beam's intensity to that of the dark irradiance. Our results are then compared to previous local treatments of the space-charge field equation. The two approaches are found to be in good agreement in the low spatial-frequency regime provided that the external bias field is sufficiently high. Conversely, in the high spatial-frequency region notable differences may exist. Relevant examples are provided.
[Comment on “Doctorate time rising sharply: How long should it take” by William Glen] Defining TTD

In response to the Forum article “Doctorate Time Rising Sharply: How long should it take?” by William Glen (March 27, 1990), I contend that Glen (and the authors of a book he cites) may be overlooking a possible explanation for the rise in time to doctorate (TTD). Is the time one spends working in his/her field between degrees considered and tabulated? It might be that after obtaining a bachelors or masters degree, the student seeks employment for a number of years before returning to school. Using myself as an example, after graduating with a masters degree in 1981 (bachelors in 1979), I worked as a research associate for NASA before returning to school in 1984. I completed my doctorate degree in 1987, making my actual time in school between the bachelors and doctorate degrees only 5 years. The TTD as defined in Forum would yield 8 years. I know of many others who have proceeded in getting a doctorate degree in a similar fashion. My TTD of 8 years in no way reflects institutional factors as suggested in the article.
Trends of Earlier and Later Responses of C-peptide to Oral Glucose Challenges With Progression to Type 1 Diabetes in Diabetes Prevention Trial–Type 1 Participants

Abstract Objective. We studied the C-peptide response to oral glucose with progression to type 1 diabetes (T1D) in Diabetes Prevention Trial-Type 1 (DPT-1) participants. Methods. Among 504 DPT-1 participants Results. The 30-0 minute C-peptide difference from OGTTs performed 2.0 years before diagnosis in progressors was lower than the 30-0 minute C-peptide difference from OGTTs performed 2.0 years before the last visit in non-progressors (p Conclusion. A decreased early C-peptide response to oral glucose and an increased later response occur at least two years before the diagnosis of T1D.
Sensitivity problems in linear systems

Several aspects of the system sensitivity problem are discussed from a function-space viewpoint. The development shows that sensitivity problems in free and forced responses of discrete, continuous, and composite systems can be treated within a common framework. The principal objective of the article is to focus attention on the ingredients required by a sensitivity measure of general applicability.
Visual Support Devices: Evaluation of a New Technique for Constructing Facial Images:

A facial recognition study explored the utility of a relatively new image generation technique – the Field Identification System (FIS). Subjects saw an FIS composite and then attempted to select the target face in a series of photographs. The effect of composite similarity (goodness-of-fit of the image with the target person) was significant, with high similarity composites leading to better recognition (30 percent hit rates). Performance with low similarity composites was no better than chance. False alarms were 20 percent overall, with no difference between conditions. The results have implications for criminal identification procedures.
Tweets of No Nation: The Correlation between Twitter Sentiment and Public Opinion in Nigeria

Could social media be used to augment traditional polling for political sentiment? Social media such as Twitter, Facebook, etc. may provide a window into public opinion that complements other sources. However, this data also has some inherent challenges related to self-selection bias of participants, accurate geolocation of users, language barriers, code-switching, and interpretation of opinion from ambiguous text. As noted in a recent study by the Pew Research Center, there can be a dissonance between reactions on Twitter and general public opinion. This study explores the links between tweets and public opinion in Nigeria. We collected approximately 14 million tweets from Nigeria from the period just before the 2011 Presidential election, down-selected those with relevant political content and compared them to election returns and contemporaneous polling data. Analyzing support for the three major candidates across Nigerias seven geopolitical zones, we found a significant correlation between election returns and mentions of candidates. Analyzing sentiment by multiple methods, we found high correlation between Twitter sentiment and poll support for a challenger but a pervasive twitter negativity bias against the incumbent. Challenges related to collections, processing, and interpretation of this data will be discussed, along with future potential of this new data source.
Electromyographic Study of Transplanted Muscles about the Knee in Poliomyelitic Patients

An electromyographic study is presented of twenty-one patients with paralysis of the lower extremity due to poliomyelitis on whom thirty-nine muscle transplantations for quadriceps insufficiency were performed. Electromyograms and gait movies were filmed simultaneously on the same movie film by specially designed apparatus. The phasic activity of each muscle studied was plotted on polar coordinate graph paper, for both the patients with poliomyelitis and for six normal control subjects. Numerous phase conversions were evident in both the transplanted and non-transplanted muscles in the patients with poliomyelitis. Extension of the phasic activity of the gluteus maximus through most of the stance phase and conversion of hamstring activity from swing to stance phase were observed in non-transplanted muscles. Ten of fourteen hamstring transplants achieved stance-phase activity roughly comparable to that of the normal quadriceps femoris. Two of eleven sartorius transplants and four of the twelve tensor transplants achieved stance-phase activity. It was noted that the tensor and sartorius transplants frequently functioned while both the hip and knee were flexing. A preliminary report is made of sartorius and tensor transplants that were converted to one-joint muscles by detachment of their proximal ends from the anterosuperior iliac spine with reattachment in the region of the greater trochanter. Some of the factors that may have bearing on phase conversion are discussed.
Probabilistic estimation of link travel times in dynamic road networks

Due to the availability of large historical and real-time traffic data, car navigation systems are becoming more and more advanced in predicting the travel time for various routes and finding the fastest route from a source to a destination given a start time. The most advanced of these systems predict the travel time of the routes, given past traffic patterns in order to find the best route. However, the best route is not necessarily a reliable route as well, i.e., the route with the least variation in possible travel times. The most reliable route is desirable when traveling with a deadline, e.g., to reach a flight at the airport or to arrive on time for an important meeting. To find the most reliable route, one needs to predict the probability distribution of travel times for that route. This in turn requires the estimation of travel time probability distributions for each and every link, given a link-entrance-time. In this paper we address the problem of computing these link travel time distributions. To the best of our knowledge there has not been any study on how to compute probability distributions for links (/edges) in road networks. We show how this first step can affect the accuracy of the travel time distribution over the entire route. Our final challenge is to evaluate the result of different approaches in computing these travel time distributions, which is difficult because the reported travel time is not a single value but a probabilistic distribution highly depending on the trip start time. We thus propose a statistical test that enables us to evaluate these outcomes.
Sound and Distortion Produced by a Braking Rotor Operating in a Planar Boundary Layer with Application to Wind Turbines

Acoustic, mean wall pressure, and PIV measurements are presented for a 10-bladed 457mm diameter rotor operating in a planar boundary layer at a variety of braking conditions and yaw angles. Turbulence ingestion and laminar/transitional boundary layer vortex trailing edge noise are important components in the total sound spectrum, the latter appearing where significant portions of the rotor disk are at low angle of attack. Mean wall pressure and PIV measurements show that the flow is accelerated through the gap between the rotor and wall and distorted by the rotor’s blockage. Acceleration through the tip gap is associated with reduction in the streamwise normal Reynolds stress. Phase-averaged velocity fields show the influence of tip leakage vortices shed from the blades.
A Model Method for Studying Norovirus

Norovirus is an extremely contagious positive sense RNA virus responsible for gastroenteritis. It has gained media attention due to its presence and impact on food and drinking water, and in the cruise ship industry. Researchers studying Norovirus have faced many challenges in their field with a limited number of reagents available for detecting the virus and growing it in culture, and no dependable small animal model. This research highlight focuses on the work of Taube et al. in the development of a mouse model for human Norovirus. This study used BALB/c mice deficient in recombination-activating genes 1 and 2 (Rag) and common gamma chain (γc) to demonstrate infection and replication of human Norovirus within the mice macrophages of the liver and spleen. They further showed the presence of human immune cells was not necessary to establish infection, but that the background strain of the mouse determined susceptibility. This discovery provides a huge step forward for basic and clinical applications of Norovirus research.
The International Endorsement of US Distress Screening and Psychosocial Guidelines in Oncology: A Model for Dissemination

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Distress Management have, since 1997, called for routine screening of distress in patients with cancer. Following the example of pain as the fifth vital sign, the case for using the concept of distress as the sixth vital sign was made by leading psycho-oncologists in 2007. Cancer care organizations in Canada and the International Psycho-Oncology Society have adopted the NCCN Guidelines for Distress Management and have named distress screening as the sixth vital sign, thereby encouraging cancer care clinicians to think of screening for distress when they screen for pain and other vital signs. Using the evidence integration triangle, this article explores the dissemination of the notion of distress as the sixth vital sign in an international context. This exploration shows that NCCN and similar organizations can adopt the evidence integration triangle in its next phase of moving toward full implementation of the NCCN Guidelines for Distress Management.
Purinergic regulation of ion transport across nonciliated bronchiolar epithelial (Clara) cells.

Previous studies demonstrated that elevation of intracellular calcium concentration ([Ca2+]i) increased electrogenic anion transport by bronchiolar epithelia. Extracellular nucleotides were shown to elevate [Ca2+]i and transepithelial short-circuit current (Isc) in proximal airways epithelia. In this study purine and pyrimidine nucleotides were investigated for their ability to regulate ion transport by rabbit nonciliated bronchiolar epithelial (Clara) cells in culture. ATP in the apical bath induced a concentration-dependent transient increase in [Ca2+]i and Isc. Mean effective doses (ED50) of the responses were 10(-7) M and 10(-6) M, respectively. Transepithelial resistance (Rt) decreased. The peak changes in Isc and Rt were 7.8 +/- 1.2 microA/cm2 and -59 +/- 14 omega.cm2 (n = 26, basal Isc = 47.4 +/- 4.3 microA/cm2 and Rt = 428 +/- 40 omega.cm2). Some preparations exhibited a small residual increase in Isc after the initial response, but the change was not statistically significant (delta Isc = 1.7 +/- 1.2 microA/cm2, n = 18). Addition of ATP to the basolateral bath had no detectable effects. Purinoceptor agonists were used to characterize the receptors mediating the change in Isc. UTP and ATP gamma S increased Isc and inhibited subsequent stimulation by ATP. ADP, ADP beta S, 2-methylthio-ATP, and alpha, beta-methylene-ATP had negligible effects on the peak delta Isc and subsequent stimulation by ATP. The ionic mechanism underlying the ATP-induced increase in Isc was investigated with the use of specific ion-transport inhibitors and by ion substitution.(ABSTRACT TRUNCATED AT 250 WORDS)
‘Barons’ Wars, under Other Names’: Feudalism, Royalism and the American Founding

SUMMARYThe Machiavellian Moment was largely responsible for establishing what remains the dominant understanding of American Revolutionary ideology. Patriots, on this account, were radical whigs; their great preoccupation was a terror of crown power and executive corruption. This essay proposes to test the whig reading of patriot political thought in a manner suggested by Professor Pocock's pioneering first book, The Ancient Constitution and the Feudal Law. The whig tradition, as he taught us, located in the remote Saxon past an ‘ancient constitution’ of liberty, in which elected monarchs merely executed laws approved by their free subjects in a primeval parliament. This republican idyll, whigs believed, was then tragically interrupted by the Norman Conquest of 1066, which introduced feudal tenures and monarchical tyranny. Did patriot theorists accept this narrative? The answer, I shall argue, is strikingly mixed. By the early 1770s, appeals to the ‘ancient constitution’ had become less common in patriot ...
Enantioselective Addition of Bromonitromethane to Aliphatic N-Boc Aldimines Using a Homogeneous Bifunctional Chiral Organocatalyst.

This report details the enantioselective synthesis of β-amino-α-bromo nitroalkanes with β-alkyl substituents, using homogeneous catalysis to prepare either antipode. Use of a bifunctional Bronsted base/acid catalyst allows equal access to either enantiomer of the products, enabling the use of Umpolung Amide Synthesis (UmAS) to prepare the corresponding L- or D-α-amino amide bearing alkyl side chains - overall, in only 4 steps from aldehyde. The approach also addresses an underlying incompatibility between bromonitromethane and solid hydroxide bases.
Edge instability in a chiral stripe domain under an electric current and skyrmion generation

Motivated by the recent experimental observations on the skyrmion creation by cutting chiral stripe domains under a current drive [Jiang et al., Science 349, 283 (2015)], we study the mechanism of skyrmion generation by simulating the dynamics of stripe domains. Our theory for skyrmion generation is based on the fact that there are two half skyrmions attached to the ends of a stripe domain. These half skyrmions move due to the coupling between the skyrmion topological charge and current. As a consequence, the stripe domain is bent or stretched depending on the direction of motion of the half skyrmions. For a large current, skyrmions are created by chopping the stripe domains via strong bending or stretching. Our theory provides an explanation to the experiments and is supported by the new experiments. Furthermore, we predict that skyrmions can also be generated using a Bloch stripe domain under a spin transfer torque which can be realized in B20 compounds.
Anti-aliasing in triangular pixels

Publisher Summary Much of graphics rendering today takes place in a square pixel grid. This is because the boundaries of the square grid are all vertical and horizontal lines, which eases the computational burden of sampling, filtering, and reconstruction. But it is well-known that the square grid is not the most uniform in terms of sampling densities. In two dimensions, the triangular lattice is more isotropic. Triangular lattice permits two tilings by regular polygons: hexagonal and triangular. Both unit cells have been used for image processing. This chapter presents an inexpensive antialiasing technique for triangular pixels. The prefiltered contribution of the polygon can be parameterized to each element of the grid by building a look-up table based on the vertices of the polygon and the polygon's intersections with the edges of the triangle. A simple box filter simply returns the amount of area within the triangle; higher-order filters may apply a weighting mask first.
Similarity- and Nonsimilarity-Based Conceptualization in Children and Pigeons

Authors including Lea (1984) have recently argued that true conceptual behavior is not based solely on perceptual similarity. We have developed a method for assessing nonsimilarity-based conceptualization in children that parallels an effective method for pigeons. This method has provided evidence that both species form classes of functionally equivalent, but perceptually different stimuli. Children and pigeons are thus capable of similarity-based and nonsimilarity-based conceptualization; in the former case differential reinforcement may be said to disclose preexisting concepts, whereas in the latter it may be said to produce new ones. The similarity of pigeons’ and children’s categorization behavior suggests that linguistic ability is not necessary for conceptualization.
The Death of Imhotep: A Hermeneutical Framework for Understanding the Lack of Black Males in STEM Fields.

In Afrocentric circles in the United States, ancient Kemetic (Egyptian) scientist Imhotep is considered the Black father of medicine. In this article, I use his name in the title as an allusion to highlight the lack of Black males matriculating in science, technology, engineering, and mathematics (STEM) programs or fields in the United States. The work offers a more appropriate structural Marxist hermeneutical framework for contextualizing, conceptualizing, exploring, and evaluating the locus of causality for the Black/White and Black male/female academic achievement gaps in general, and the lack of Black males in STEM programs in the United States of America in particular. The two I argue are interrelated. Positing that in general the origins of the Black/White and Black male/female academic achievement gap is grounded in what Paul C. Mocombe refers to as a “mismatch of linguistic structure and social class function.” Within Mocombe’s structural Marxist theoretical framework, the lack of Black males in S...
RAD: Reactive Airways Disease or Really Asthma Disease?

* Abbreviation: RAD — : reactive airways disease A resident presenting on rounds introduces her patient as “a 15-month-old with RAD. He’s had 2 days of wheezing, and we started albuterol and steroids.” A presentation like this is frequently heard on pediatric units despite the vagueness of the term “reactive airways disease,” commonly referred to as “RAD.” The term is often used as a substitute for asthma in young children on asthma medications when pediatricians are reticent to use the “A word.” Yet RAD has no accepted definition and does not add any specificity to the medical vocabulary. The reluctance to use the term “asthma” in a patient in whom asthma medications are being administered, no matter the age, is perplexing. In a field whose terminology is extensive enough to constitute its own language, it is surprising that we have allowed such a term to slip into the medical lexicon. Recently, members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Pediatric Society to reevaluate clinical practice surrounding the diagnosis and management of asthma in preschoolers.1 Their position paper asserts that RAD, and other vague and nondiagnostic terms, be abandoned. Accordingly, we call on the analogous pediatric and respiratory societies in the United States and around the world to discourage the continued use of “RAD” across medical settings and … Address correspondence to Lindsey C. Douglas, MD, MS, Department of Pediatrics, The Children’s Hospital at Montefiore, 3415 Bainbridge Ave, Bronx, NY 10467. E-mail: douglas{at}montefiore.org
Fire retardant, superionic solid state polymer electrolyte membranes for lithium ion batteries

Recent advances on polymer electrolyte membranes (PEM) are reviewed with emphasis on fabrication and evaluation of electrochemical performance of solid PEMs consisted of photo-curable polymer precursor, lithium salt, and solid plasticizer. Guided by the phase diagram of ternary mixtures of poly(ethylene glycol) derivatives, lithium bis(trifluoromethane)sulfony imide (LiTFSI) salt, and succinonitrile (SCN) plasticizer, the achievement of completely amorphous, solid PEMs has been demonstrated. These solid PEM films are stretchable, thermally stable, and flame-retardant, showing enhanced high ionic conductivity on the level of superionic conductors. Electrochemical stability of the PEM has been tested in half-cell configurations using LiFePO4 and Li4Ti5O12 electrodes against lithium foil counter electrode and their future prospects are discussed.
Characterization of T-Cell Lymphoblastic Leukemia Genetic Etiology

Abstract 5128 Introduction. T-cell lymphoblastic leukemia (T-ALL) is inflict nearly 1500 children annually in the US. We recently reported using Sleeping Beauty mutagenesis as a forward genetics approach to model two major subtypes of T-ALL, typical and early T-cell precursor (ETP). The genetic mutations that define these subtypes is incomplete. Moreover, identifying driver from passenger mutations within these tumors is paramount for developing targeted therapeutics to specific genetic lesions. Method. T-ALL tumors were generated using a Cre-inducible Sleeping Beauty system to drive mutagenesis at either early (Vav-iCre) or late (CD4-Cre) stage of T-cell development. Synthetic gene standards were spiked into samples at known concentrations to permit quantitation of transposon insertion events within individual tumors. Samples were prepared by ligation mediated PCR and sequenced using an Illumina HiSeq. Using the standard as a barometer, common insertion sites (CIS) were defined as initiating, transition, or progression based on their abundance. We further developed a network analysis pathway to identify CISs within similar signaling axes. Results. Spiked standards were reproducibly seen at expected abundances in several replicated tumors. Further, we are able to distinguish insertions found at high abundances in tumors from lower occurring or background events. Together this allowed us to identify the order of mutations in each tumor and characterize mutations as initiators or progression events. Using our network analysis pathway we found Myc and Stat5b signaling axes driving the majority of ETP-ALL and Notch1 signaling driving typical T-ALL. Conclusions. Our data are the first to utilize NextGen sequencing techniques to quantitate CIS events to understand the genetic etiology of T-ALL. Coupled with our network analysis software, we are able to more accurately identify driving pathways in individual T-ALL tumors induced by Sleeping Beauty mutagenesis. Disclosures: No relevant conflicts of interest to declare.
Contraceptive use at first intercourse among Jewish women in Israel, 1962–1988

Using data from the 1987–1988 Study of Fertility and Family Formation,this study examines the family planning practices of Jewish Israeli womenwho first had intercourse between 1962 and 1988. The overwhelming majorityof women reported using no contraception at first intercourse, and among those who did practice birth control approximately half relied on modern techniques. While the likelihood that Israeli women used contraception at first sex changed little between 1962 and 1988, there has been a marked shift towards the adoption of efficient methods of birth control. Moreover, factors which promote female empowerment, including education and military service, have been positively associated with contraceptive use at first intercourse. Among those women who practiced contraception at first intercourse, those from Africa and Asia have been especially likely to make use of inefficient methods such as withdrawal.
Tobacco biomarkers and genetic/epigenetic analysis to investigate ethnic/racial differences in lung cancer risk among smokers

The Multiethnic Cohort Study has demonstrated that African Americans and Native Hawaiians have a higher risk for lung cancer due to cigarette smoking than Whites while Latinos and Japanese Americans have a lower risk. These findings are consistent with other epidemiologic studies in the literature. In this review, we summarize tobacco carcinogen and toxicant biomarker studies and genetic analyses which partially explain these differences. As determined by measurement of total nicotine equivalents in urine, which account for about 85% of the nicotine dose, African Americans take up greater amounts of nicotine than Whites per cigarette while Japanese Americans take up less. There are corresponding differences in the uptake of tobacco smoke carcinogens such as tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, 1,3-butadiene, and other toxic volatiles. The lower nicotine uptake of Japanese Americans is clearly linked to the preponderance of low activity forms of the primary nicotine metabolizing enzyme CYP2A6 in this ethnic group, leading to more unchanged nicotine in the body and thus lower smoking intensity. But the relatively high risk of Native Hawaiians and the low risk of Latino smokers for lung cancer are not explained by these factors. The possible role of epigenetics in modifying lung cancer risk among smokers is also discussed here. The results of these published studies may lead to a better understanding of susceptibility factors for lung cancer in cigarette smokers thus potentially identifying biomarkers that can detect those individuals at highest risk so that preventive approaches can be initiated at an early stage of the lung cancer development process.
Considerations for Supporting Faculty in Transitioning a Course to Online Format

The move toward offering more online instruction at many academic institutions frequently takes the form of conversion of a traditional course to online format. Despite its prevalence, this special form of course development has received little research attention. This paper presents the results of an exploratory study of the faculty perspective on the process of course conversion and handling of associated pedagogical and technical challenges as well as institutional factors and administrative considerations. Semi-structured personal interviews were conducted with eleven instructors from three universities. The study was focused on key decisions related to course redesign, such as motivation for conversion, content modification and format of presentation, delivery and development technology, as well as changes to pedagogical strategies. Main factors impacting these decisions are identified and analyzed in terms of their relative influence. The need for greater flexibility in technical and administrative support of the course conversion efforts by faculty are discussed along with other practical implications and possible directions for further study.
Fundamental limits of networked sensing: the flow optimization framework

We describe a useful theoretical approach--the flow optimization framework --that can be used to identify the fundamental performance limits on information routing in energy-limited wireless sensor networks. We discuss the relevant recent literature, and present both linear constant-rate and non-linear adaptive rate models that optimize the tradeoff between the total information extracted (Bits) and the total energy used (Joules) for a given sensor network scenario. We also illustrate the utility of this approach through examples, and indicate possible extensions.
Constellation shaping for high symbol rate SNR limited transceivers

The information rate (IR) of a digital coherent transceiver is constrained by the inherent practical signal-to-noise ratio (SNR) limit. Coded modulation, which is the combination of multi-level modulation and forward error correction, aims to maximize the IR within this SNR envelope. While probabilistic constellation shaping has enhanced this methodology by providing an increase in IR over conventionally employed square quadrature amplitude modulation (QAM) formats, it is the ability to eloquently tune the per wavelength IR by varying the symbol probabilities that has gained this scheme significant traction within optical communications in recent years. As commercial line cards continue their evolution towards 100 GBd and to modulation formats beyond 64QAM, we discuss the merits of probabilistic shaping for high symbol rate digital coherent transceivers in the presence of a practical SNR limit.
Beyond Average Tools. On the use of ‘dumb’ computation and purposeful ambiguity to enhance the creative process

(2019). Beyond Average Tools. On the use of ‘dumb’ computation and purposeful ambiguity to enhance the creative process. The Design Journal: Vol. 22, Running with Scissors: 13th International Conference of the European Academy of Design, Dundee, 10-12th April, 2019, edited by Louise Valentine, Joanna Bletcher and Leon Cruickshank, pp. 1147-1161.
Visions of stagnation and maldistribution: monopoly capital, ‘white monopoly capital’ and new challenges to the South African Left

The term ‘white monopoly capital’ (WMC) has featured prominently in South Africa's recent popular economic discourse. Situating this rhetorical turn within discussion over the broader monopoly capi...
Trace Element Concentrations in Hydrothermal Silica Deposits as a Potential Biosignature.

Uncovering and understanding the chemical and fossil record of ancient life is crucial to understanding how life arose, evolved, and distributed itself across Earth. Potential signs of ancient life...
Renal artery angiography in pediatric trauma using a national data set.

Summary Introduction With limited pediatric renal trauma management literature, treatment pathways for children have been extrapolated from the adult population. A shift to non-operative management has led to higher renal preservation rates; however, characterization of endovascular intervention in the pediatric trauma population is lacking. Objective This study uses the National Trauma Data Bank (NTDB), to evaluate renal outcomes after use of renal artery angiography. We hypothesized that patients undergoing renal artery angiography for renal trauma are unlikely to require additional surgical interventions. Study design All children ≤18 years old treated for traumatic renal injuries from 2012 to 2015 were identified by the Abbreviated Injury Scaled Score (AISS) codes in the NTDB. AISS codes were converted to American Association for Surgery of Trauma (AAST) grades. ICD-9 codes were used to identify patients that had renal artery angiography, and additional renal interventions such as nephrectomy, partial nephrectomy, percutaneous nephrostomy tube or ureteral stent placement. Results 536,379 pediatric trauma cases were in the NTDB from 2012 to 2015, with 4506 renal injury cases identified. A total of 88 patients had renal artery angiography (ICD-9 88.45). Only 10% (n = 9) of patients who received renal artery angiography underwent an additional urological intervention. Of those nine, two patients were excluded due to renal angiography taking place after nephrectomy was performed. The remaining seven patients had high grade laceration (AAST grade 4-5). Overall, two patients underwent post angiography nephrectomies, two patients had partial nephrectomies, one percutaneous nephrostomy tube was placed (prior to partial nephrectomy), one aspiration of a kidney (prior to ureteral stent placement), and three had ureteral stent placements. Discussion The limitations of this study include: the NTDB is a national dataset that is not population based, inclusion is limited to the first hospitalization, inaccuracies exist in encounter coding, and the database is lacking laterality of the renal injury. Based on nonspecific nature of ICD-9 coding for angioembolization, we are unable to discern the number of cases that subsequently had angioembolization after or at the time of angiography. Conclusion Renal artery angiography in children remains a rare procedure, 88/4,506, in children with renal trauma. In pediatric trauma cases that undergo renal artery angiography additional procedures are more common with higher grade injuries. Further studies are needed to create pediatric specific trauma management algorithms. Summary Table Patient Characteristics (N = 88/4506) Female 25 (29%) Age in years (median, IQR) 16 (13–18) Mechanism of trauma Blunt trauma 88% (n = 77) Penetrating trauma 9% (n = 8) Unspecified 3% (n = 3) AAST Renal Injury Grade Grade I 6 Grade II 10 Grade III 24 Grade IV 38 Grade V 10 Number patients who had urologic procedures performed after RAA 8% (n = 7) IQR = interquartile range; AAST = American Association for the Surgery of Trauma; RAA = Renal Artery Angiography.
A 28-mW 32-Gb/s/pin 16-QAM Single-Ended Transceiver for High-Speed Memory Interface

A 32-Gb/s low-power single-ended 16-QAM transceiver using four signal levels is presented for high-speed memory interface. With four-bit per symbol, the transceiver increases the symbol period by 4× to enhance energy-efficiency by reducing the bandwidth requirement for most circuit blocks and mitigating equalization requirements. The transmitter achieves 16-QAM modulation by combining two QPSK modulators for linearity relaxation. Taking advantage of the DC-balanced 16-QAM signal, the receiver adopts a low-noise single-to-differential amplifier with a low-power DC feedback to recover the signal without requiring an external reference. The proposed transceiver achieves 0.875 pJ/bit at full rate while occupying 0.018 mm2 in 28-nm CMOS technology.
Impact of Zero Cost Books Adoptions on Student Success at a Large, Urban Community College

This article examines the impact of Zero Cost Textbooks (ZCB) courses on two key factors of students success: pass rates and completion rates. We examine three years of data at Houston Community College, ending with the first year of their implementation of a ZCB program. Following the "access hypothesis," we suppose that students who would not otherwise be able to purchase traditional textbooks will have higher pass rates and completion rates in ZCB courses. We use Pell recipient status and ethnicity as proxies for socio-economically disadvantaged students, targeting those populations where the access hypothesis will have the greatest impact. We isolate faculty who taught both ZCB and non-ZCB courses during the period under review and conduct a post-hoc analysis, using mixed effects logistic regression, to identify interactions between student and course characteristics and success metrics. We find that HCC's ZCB program had a statistically significant positive effect on pass rates for all students, but no effect on completion. We find a trend to suggest the ZCB program may improve success among Black students, but only a statistically significant positive effect among Asian students, and no interaction with Pell recipient status. These results are not well explained by the access hypothesis; they suggest the need for further research.
When nothing looks blue

Pitt (Analysis 77(4):735–741, 2017) has argued that reductive representationalism entails an absurdity akin to the “paramechanical hypothesis” Ryle (The concept of mind, Hutchinson, London, 1949) attributed to Descartes. This paper focuses on one version of reductive representationalism: the property-complex theory. We contend that at least insofar as the property-complex theory goes, Pitt is wrong. The result is not just a response to Pitt, but also a clarification of the aims and structure of the property-complex theory.
The riddle of the Sphinx: why sphingosine-1-phosphate may help define molecular mechanisms underlying risk stratification for serious COVID-19 infections.

The sphingosine-1-phosphate (S1P) is a lysophospholipid signaling molecule with important functions in many physiological and pathological conditions, including viral infection. In this issue of EMBO Molecular Medicine, Marfia et al present a risk stratification based on S1P serum level as a novel prognostic indicator for COVID-19 severity.
Current and near-term advances in Earth observation for ecological applications

There is an unprecedented array of new satellite technologies with capabilities for advancing our understanding of ecological processes and the changing composition of the Earth's biosphere at scales from local plots to the whole planet. We identified 48 instruments and 13 platforms with multiple instruments that are of broad interest to the environmental sciences that either collected data in the 2000s, were recently launched, or are planned for launch in this decade. We have restricted our review to instruments that primarily observe terrestrial landscapes or coastal margins and are available under free and open data policies. We focused on imagers that passively measure wavelengths in the reflected solar and emitted thermal spectrum. The suite of instruments we describe measure land surface characteristics, including land cover, but provide a more detailed monitoring of ecosystems, plant communities, and even some species then possible from historic sensors. The newer instruments have potential to greatly improve our understanding of ecosystem functional relationships among plant traits like leaf mass area (LMA), total nitrogen content, and leaf area index (LAI). They provide new information on physiological processes related to photosynthesis, transpiration and respiration, and stress detection, including capabilities to measure key plant and soil biophysical properties. These include canopy and soil temperature and emissivity, chlorophyll fluorescence, and biogeochemical contents like photosynthetic pigments (e.g., chlorophylls, carotenoids, and phycobiliproteins from cyanobacteria), water, cellulose, lignin, and nitrogen in foliar proteins. These data will enable us to quantify and characterize various soil properties such as iron content, several types of soil clays, organic matter, and other components. Most of these satellites are in low Earth orbit (LEO), but we include a few in geostationary orbit (GEO) because of their potential to measure plant physiological traits over diurnal periods, improving estimates of water and carbon budgets. We also include a few spaceborne active LiDAR and radar imagers designed for quantifying surface topography, changes in surface structure, and 3-dimensional canopy properties such as height, area, vertical profiles, and gap structure. We provide a description of each instrument and tables to summarize their characteristics. Lastly, we suggest instrument synergies that are likely to yield improved results when data are combined.
The clinical behavior and genomic features of the so-called adenoid cystic carcinomas of the solid variant with basaloid features.

Classic adenoid cystic carcinomas (C-AdCCs) of the breast are rare, relatively indolent forms of triple negative cancers, characterized by recurrent MYB or MYBL1 genetic alterations. Solid and basaloid adenoid cystic carcinoma (SB-AdCC) is considered a rare variant of AdCC yet to be fully characterized. Here, we sought to determine the clinical behavior and repertoire of genetic alterations of SB-AdCCs. Clinicopathologic data were collected on a cohort of 104 breast AdCCs (75 C-AdCCs and 29 SB-AdCCs). MYB expression was assessed by immunohistochemistry and MYB-NFIB and MYBL1 gene rearrangements were investigated by fluorescent in-situ hybridization. AdCCs lacking MYB/MYBL1 rearrangements were subjected to RNA-sequencing. Targeted sequencing data were available for 9 cases. The invasive disease-free survival (IDFS) and overall survival (OS) were assessed in C-AdCC and SB-AdCC. SB-AdCCs have higher histologic grade, and more frequent nodal and distant metastases than C-AdCCs. MYB/MYBL1 rearrangements were significantly less frequent in SB-AdCC than C-AdCC (3/14, 21% vs 17/20, 85% P < 0.05), despite the frequent MYB expression (9/14, 64%). In SB-AdCCs lacking MYB rearrangements, CREBBP, KMT2C, and NOTCH1 alterations were observed in 2 of 4 cases. SB-AdCCs displayed a shorter IDFS than C-AdCCs (46.5 vs 151.8 months, respectively, P < 0.001), independent of stage. In summary, SB-AdCCs are a molecularly heterogeneous but clinically aggressive group of tumors. Less than 25% of SB-AdCCs display the genomic features of C-AdCC. Defining whether these tumors represent a single entity or a collection of different cancer types with a similar basaloid histologic appearance is warranted.
Making the most of metal ions

Crystal structures of the homing endonuclease I-CreI bound to substrate DNA and divalent metals show that one metal ion is shared between the two active sites of the enzyme. This arrangement appears uniquely suited to the formation of double-stranded DNA breaks via a concerted reaction.
Quantitative formation of N(O,S)-heptafluorobutyryl isobutyl amino acids for gas chromatographic analysis

The effect of temperature, reaction time and HCL concentration on the formation of the isobutyl esters of protein amino acids has been studied. Quantitative esterification is achieved by heating at 120° for 30 min in 3 M HCl-isobutanol. Experimental procedures have been examined in detail and potential sources of error in derivatisation and chromatography have been identified.
Seed set in Guayule (Parthenium argentatum, asteraceae) in relation to insect pollination

Guayule (Tarthenium argentatum, Asteraceae) is one of two major plant species grown for natural rubber. Studies were conducted to determine the effect of honey bee (Apis mellifera) pollination and season on seed set and total seed yield/ha. The experiments involved four pollination treatments: plants caged with bees; plants caged without bees; plants open pollinated (uncovered); and plants individually covered. Seeds were harvested monthly July–September 1984, and May–September 1985. Plots with bees produced at least 150% more seeds than plots without bees, and there were no qualitative differences in the seed weights among treatments. Highest seed yield was in May and September. Results indicate that (1) insect pollination in guayule increases seed yield and (2) fewer seeds are produced in the warmest months.
Heterostructure MESFET devices for VLSI applications

Manufacturing of heterostructure ICs at VLSI integration levels has heretofore not been realized. Recently, epitaxial material quality and availability has improved dramatically with the proliferation of low-pressure metalorganic-chemical-vapor-deposition (LP-MOCVD) material. In addition, the quality of GaAs IC manufacturing has steadily improved in integration level and density of interconnect. As a result, complexity consistent with the fabrication of VLSI structures is now feasible using LP-MOCVD material with H-MESFET technology. Results are presented which were obtained using the H-MESFET approach to achieve high density, VLSI complexity GaAs ICs. >
Developing an intelligent tutoring system using natural language for knowledge representation

Authoring the domain knowledge of an intelligent tutoring system (ITS) is a well-known problem, and an often-mentioned approach is to use authors who are domain experts Unfortunately, this approach requires that potential authors learn to write and debug knowledge written in a formal knowledge representation language If authors were able to use natural language to represent knowledge it would allow them to add and update knowledge far more easily In this paper, the design of such an authoring system, ‘Natural-K' is presented Natural-K is an authoring system in which domain authors including non-programmers are able to add problem statements and background knowledge such as commonsense, in natural language.