cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal placement of known symbols for slowly varying frequency-selective channels

The problem of placing known symbols in a data stream for a slowly varying frequency-selective channel is considered from an information-theoretic perspective. Given the amount of redundancy associated with known symbols, placement schemes that minimize the outage probability are derived by assuming that the transmitted codewords consist of packets that are constrained to have the same known symbol placement. Under the assumption that each known symbol cluster is at least as large as /spl alpha/ /spl ges/ 2L + 1 (where L is the channel order), we show that the optimal placement is obtained by arranging the known symbols into as many clusters as possible and placing them such that the unknown symbol blocks are as equal as possible. It is shown that the optimal placement of known symbol clusters does not depend on the probability density of the channel. Numerical examples are used to illustrate the ideas and potential gains of using optimal known symbol placement.
Effect of London forces upon the rate of deposition of Brownian particles

Rates of deposition of particles onto a spherical collector, immersed in a creeping fluid, are calculated as a function of Peclet number, aspect ratio, and the ratio of Hamaker's constant to kT for all cases of practical importance involving convective-diffusion and London forces. Boundaries of regions where London forces or Brownian motion may be neglected are established in terms of the above dimensionless groups. Gravitational forces were included in the calculations for some representative conditions but may be neglected for small or neutrally buoyant particles or for high flow rates. Close agreement was noted between deposition rates calculated by summing individual contributions from each transport mechanism and deposition rates calculated from a rigorous consideration of their combined effect. Thus the additivity rule was verified for the cases studied.
Top Manager Effects on Buprenorphine Adoption in Outpatient Substance Abuse Treatment Programs

To examine the influence of top managers’ characteristics on the adoption of buprenorphine for opioid dependence among U.S. outpatient substance abuse treatment units, this investigation analyzed a cross-sectional national study of 547 such units in the 2004–2005 wave of the Drug Abuse Treatment System Survey. Administrators reported their demographics, training, and treatment orientation, as well as features of the unit and its pattern of use of buprenorphine. Nationally, 15.8% of programs offered any buprenorphine services. Greater adoption of buprenorphine correlated with directors’ younger age, longer tenure, male gender, and weaker endorsement of abstinence as the most important treatment goal. Availability of naltrexone and medical services also correlated positively with buprenorphine adoption. The authors conclude that leaders’ characteristics are related to the adoption of innovative practices in addiction treatment programs. Future work should examine whether leadership development for community addiction programs might speed up the diffusion of buprenorphine and other innovative, evidence-based practices.
Additives that prevent or reverse cathode aging in drift chambers with helium-isobutane gas

Noise and Malter breakdown have been studied at high rates in a test chamber having the same cell structure and gas as in the BaBar drift chamber. The chamber was first damaged by exposing it to a high source level at an elevated high voltage, until its operating current at normal voltages was below 0.5nA/cm. Additives such as water or alcohol allowed the damaged chamber to operate at 25 nA/cm, but when the additive was removed the operating point reverted to the original low value. However with 0.02% to 0.05% oxygen or 5% carbon dioxide the chamber could operate at more than 25 nA/cm, and continued to operate at this level even after the additive was removed. This shows for the first time that running with an O{sub 2} or CO{sub 2} additive at high ionization levels can cure a damaged chamber from breakdown problems.
The INO80 ATP-Dependent Chromatin Remodeling Complex Is a Nucleosome Spacing Factor

The mobilization of nucleosomes by the ATP-dependent remodeler INO80 is quite different from another remodeler (SWI/SNF) that is also involved in gene activation. Unlike that recently shown for SWI/SNF, INO80 is unable to disassemble nucleosomes when remodeling short nucleosomal arrays. Instead, INO80 more closely resembles, although with notable exceptions, the nucleosome spacing activity of ISW2 and ISW1a, which are generally involved in transcription repression. INO80 required a minimum of 33 to 43 bp of extranucleosomal DNA for mobilizing nucleosomes, with 70 bp being optimal. INO80 prefers to move mononucleosomes to the center of DNA, like ISW2 and ISW1a, but does so with higher precision. Unlike ISW2/1a, INO80 does not require the H4 tail for nucleosome mobilization; instead, the H2A histone tail negatively regulates nucleosome movement by INO80. INO80 moved arrays of two or three nucleosomes with 50 or 79 bp of linker DNA closer together, with a final length of ∼30 bp of linker DNA or a repeat length of ∼177 bp. A minimum length of >30 bp of linker DNA was required for nucleosome movement and spacing by INO80 in arrays.
Neural network and conventional classifiers for fluorescence-guided laser angioplasty

The ability of the back-propagation and K-nearest-neighbors techniques to classify arterial fluorescence spectra is investigated. Both methods are competitive with other classification schemes. The best validation set accuracy on the aortic data was obtained by the 1-nearest-neighbor method (98% correct overall on the test exemplars). The 22-8-1 and 22-8-4-1 networks performed second best, misclassifying only one more exemplar, at 96%. All performances on the coronary data were much poorer. The relative performance of variations on both techniques is used to make inferences about the geometry of the classification task. >
Adaptive path planning: algorithm and analysis

We present a learning algorithm that improves path planning by using past experience to enhance future performance. The algorithm relies on an existing path planner to provide solutions to difficult tasks. From these solutions, an evolving sparse network of useful robot configurations is learned to support faster planning. More generally, the algorithm provides a framework in which a slow but effective planner may be improved both cost-wise and capability-wise by a faster but less effective planner coupled with experience. We analyze the algorithm by formalizing the concept of improvability and deriving conditions under which a planner can be improved within the framework. The analysis is based on two stochastic models, one pessimistic (on task complexity), the other randomized (on experience utility). Using these models, we derive quantitative bounds to predict the learning behavior. We use these estimation tools to characterize the situations in which the algorithm is useful and to provide bounds on the training time. In particular, we show how to predict the maximum achievable speedup.
Sinonasal Tract Inflammation as a Precursor to Nasopharyngeal Carcinoma A Systematic Review and Meta-Analysis

ObjectiveChronic inflammation has been described as a precursor to the development of malignancy in several disease states. However, the relationship of sinonasal tract inflammation to nasopharyngeal carcinoma (NPC) remains poorly defined.Data SourcesSystematic review of primary studies identified through PubMed, EMBASE, MEDLINE, and Cochrane.Methods ReviewSystematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. MEDLINE, EMBASE, and Cochrane databases were queried for English-language studies published between 1980 and 2015. Studies were excluded that did not provide quantitative data on sinonasal tract inflammation such as chronic rhinosinusitis (CRS), allergic rhinitis (AR), or human papillomavirus (HPV) status and NPC. An itemized assessment of the risk of bias was conducted for each included study.ResultsOf the 325 studies identified during systematic review, 5 met the criteria for analysis. The level of...
Tunability of short-channel effects in MoS2 field-effect devices.

MoS2 transistors have been electrically characterized and analyzed in terms of their vulnerability to short channel effects and their response to various environments. We find that the electrical performance of MoS2 flakes is governed by an unexpected dependence on the effective body thickness of the devices that in turn depends on the amount of intercalated water molecules that exist in the layered structure. In particular, a decrease in effective body thickness is observed in air compared to the “water-free” scenario. Moreover, we find that the doping stage of a MoS2 field-effect transistor (FET) is p-type despite the appearance of electron conduction, and the amount of p-doping is higher in air than in vacuum. Most importantly, our results indicate that device characteristics of MoS2 can be substantially impacted by tuning the device electrostatics. This can be accomplished by controlling the effectively active body thickness of the MoS2 FET employing intercalation and engineering of the effective barr...
Building a Robust Tumor Profiling Program: Synergy between Next-Generation Sequencing and Targeted Single-Gene Testing

Next-generation sequencing (NGS) is a powerful platform for identifying cancer mutations. Routine clinical adoption of NGS requires optimized quality control metrics to ensure accurate results. To assess the robustness of our clinical NGS pipeline, we analyzed the results of 304 solid tumor and hematologic malignancy specimens tested simultaneously by NGS and one or more targeted single-gene tests (EGFR, KRAS, BRAF, NPM1, FLT3, and JAK2). For samples that passed our validated tumor percentage and DNA quality and quantity thresholds, there was perfect concordance between NGS and targeted single-gene tests with the exception of two FLT3 internal tandem duplications that fell below the stringent pre-established reporting threshold but were readily detected by manual inspection. In addition, NGS identified clinically significant mutations not covered by single-gene tests. These findings confirm NGS as a reliable platform for routine clinical use when appropriate quality control metrics, such as tumor percentage and DNA quality cutoffs, are in place. Based on our findings, we suggest a simple workflow that should facilitate adoption of clinical oncologic NGS services at other institutions.
Innovation application of GPRS/CDMA communication network in city flood prevention system

The urbanization level of China is in a period of rapid developing.City as the area of dense population and economic factor accumulation,its monitoring and early warning of disasters is on a very prominent position.City flood prevention and forecast system can provide basic support for flood prevention decision-making departments,thus to ensure the human life and property of the city.The accuracy and real-time performance of data transmission system is particularly important.The innovation application of GPRS/CDMA communication network in city flood prevention system is introduced through practical application in a large city flood prevention and forecasting project of Shanghai.
Leukocyte reduction of red cells when transfusing patients with autoimmune hemolytic anemia: A strategy to decrease the incidence of confounding transfusion reactions

Autoimmune hemolytic anemia (AIHA) presents a difficult challenge to clinicians and blood bankers alike. Autoantibodies in the serum significantly complicate serologic evaluation, and necessitate performing procedures such as adsorptions to eliminate the possibility of underlying alloantibodies. In many instances the blood that is issued may be phenotypically similar but remains crossmatch incompatible, generating a considerable degree of anxiety among the clinical staff who are responsible for transfusing the patient. We report a case of warm autoimmune hemolytic anemia (WAIHA) in which the transfusion of red cells was complicated by a febrile transfusion reaction. Evaluation of the reaction resulted in a significant delay in transfusion therapy. Subsequent administration of leukocyte-poor red cells resulted in uneventful transfusions with a good therapeutic response. Retrospective analysis of the pretransfusion sample demonstrated significant levels of anti-neutrophil antibodies. This case resulted in the establishment of our policy to administer all red cell transfusions to patients with autoantibodies (warm or cold) as leukocyte- poor red cells.
Vitamin D-Binding Protein; Role in Osteoporosis

Osteoporosis is a bone disease, leading to an increased fracture risk. It is considered a complex multifactorial genetic disorder with interaction of environmental and genetic factors. As a candidate, vitamin D-binding protein (DBP), which binds to and transports vitamin D to target tissues to maintain calcium homeostasis through the vitamin D endocrine system, can also be converted to DBP-macrophage activating factor, which mediates bone resorption by directly activating osteoclasts. Osteoporosis is defined as a reduction in bone mass deterioration of bone microarchitecture, resulting in increased bone fragility and increased fracture risk. It is a complex disorder with interaction between environmental (e.g., low calcium intake) and genetic factors.
Untersuchung 2: Systembewusstsein und Reaktionsfähigkeit

Gegenstand dieses Kapitels ist die zweite Fahrsimulatorstudie zur Betrachtung der Uberwachungsleistung sowie der Reaktionsfahigkeit des Fahrers bei handlungsrelevanten Situationen innerhalb der teilautomatisierten Fahrt. Das zuvor praferierte HMI-Konzept hat sich dabei subjektiv bewahrt, muss jedoch unter potentiellen Systemgrenzen und -fehlern weitergehend untersucht werden. Dabei ist die Entdeckung dieser handlungsrelevanten Situationen sowie die Ubernahmefahigkeit des Fahrers entscheidend, um den Einfluss des Konzepts auf das Situationsbewusstsein und die Uberwachungsleistung bewerten zu konnen.
The Historical Perspective

This chapter discusses the historical perspective of energy and its use. Coal was introduced for heating and metallurgy in England during the 12th century and it spread rapidly to the continent. The need for pumping large amounts of water from deep mines provided the impetus for research. Petroleum was produced from shallow dug wells for many years in Poland, Romania, and Russia. The improvement of the internal combustion engine by Gottlieb Daimler, and the invention of the diesel engine by Rudolf Diesel, made oil the lifeblood of transportation within a few decades after the end of the 19th century. Energy use in transportation grows in the United States by a rate of 6.5% each year. Because of environmental considerations, pollution control, and public safety, the difficulty of producing enough raw energy is growing. International political difficulties create potential shortages in oil. Government regulations also have an adverse effect on oil and gas production. Air pollution and anti-strip mining regulations make the utilization of coal difficult. Lack of research support retards the development of new energy production schemes.
Direct Laser Metal Deposition Process Fabricates Near-Net-Shape Components Rapidly

(1995). Direct Laser Metal Deposition Process Fabricates Near-Net-Shape Components Rapidly. Materials Technology: Vol. 10, No. 3-4, pp. 51-54.
A Maximum-likelihood Approach To PET Emission/attenuation Image Registration

An algorithm for retrospective registration of PET emission and attenuation images is introduced based upon the assumption that no activity should be present outside the body. Since the attenuation image defines anatomy, it is segmented to identify a foreground template of the subject. This template is mapped to the emission image by a geometric transformation, and the emission image pixels that do not correspond to the foreground template are considered the background pixels for that transformation. An optimal geometric transformation mapping the foreground template to the emission image is sought by maximizing the likelihood of the background emission image pixels given a background intensity distribution; this background intensity distribution is estimated from the background pixels for the initial position of the template. The current implementation of the algorithm is confined to 2-D rigid motion, although these constraints are not fundamental to the method. In a preliminary phantom study where the phantom was moved between the acquisition of emission and attenuation data, the registration algorithm predicted the rotation to within five degrees (worst case) and usually to within three degrees, and it predicted the translation to within one and a half pixels; it predicted the rotation to within one degree and the translation within one pixel when performed on images reconstructed with a matching attenuation image. Possible improvements to the algorithm are suggested, based on the observation that the predicted motion is biased by the attenuation correction artifact in the images.
Attitudes and motivation of second language learners in Kuwait

This study examined attitudes and motivation of second language learners in Kuwait. A self-report questionnaire was adapted from Gardner's (1985) Attitude and Motivation Test Battery and translated into Arabic, the participants' first language. Several methods were used in dealing with the data collected: descriptive statistics, correlation, and t-test. Scores on each measure were used as separate variables to examine the relationship between any two variables (nine hypotheses). The findings were consistent with those of the other researchers': there are significant correlations between affective variables (attitudes and motivation) and learning a second language. Also, a significant level of English class anxiety was revealed upon which future investigations were recommended. Pedagogical implications were proposed in an effort to enhance the learners' interest in learning a second
Oral cannabidiol does not produce a signal for abuse liability in frequent marijuana smokers

Abstract Background Cannabidiol (CBD) is a naturally occurring constituent of the marijuana plant. In the past few years, there has been great interest in the therapeutic effects of isolated CBD and it is currently being explored for numerous disease conditions (e.g., pain, epilepsy, cancer, various drug dependencies). However, CBD remains a Schedule I drug on the U.S. Controlled Substances Act (CSA). Despite its status, there are no well-controlled data available regarding its abuse liability. Methods Healthy, frequent marijuana users (n = 31) were enrolled in this within subject, randomized, placebo-controlled, double-blind, multisite study that administered oral cannabidiol (0, 200, 400, 800 mg) alone and in combination with smoked marijuana (0.01%, 5.3–5.8% THC). Participants received one dose combination across 8 once-weekly outpatient sessions (7.5 h). The primary findings on the drug interaction effects were previously reported ( Haney et al., 2016 ). The present study is a secondary analysis of the data to examine the abuse liability profile of oral cannabidiol (200, 400, 800 mg) in comparison to oral placebo and active smoked marijuana (5.3–5.8% THC). Results Active marijuana reliably produced abuse-related subjective effects (e.g., high) (p 0.05). Conclusions Overall, CBD did not display any signals of abuse liability at the doses tested and these data may help inform U.S. regulatory decisions regarding CBD schedule on the CSA.
Thioformaldehyde S-Sulfide, Sulfur Analogue of the Criegee Intermediate: Structures, Energetics, and Rovibrational Analysis.

The ephemeral Criegee intermediate, first postulated over 70 years ago, has only recently been isolated in the gas phase. The sulfur analogue of this canonical zwitterion, thioformaldehyde S-sulfide, has eluded similar analysis; however, argon matrix isolation has been achieved (Angew. Chem., Int. Ed. 2001, 40, 393−396). Here thioformaldehyde S-sulfide and its valence isomer dithiirane are examined with high-level coupled-cluster methods, including the minimum-energy pathway for interconversion. Relative enthalpies calculated from extrapolated energies at the complete basis set limit of the full CCSDTQ method are reported. Isomerization from thioformaldehyde S-sulfide to the lower-lying dithiirane (−7.2 kcal mol–1) is predicted to include a 27.0 kcal mol–1 barrier. Harmonic and anharmonic vibrational frequencies are also predicted using second-order vibrational perturbation theory. These results should aid in future gas-phase identification.
Consequences of Chemotherapy Induced Myelosuppression In Patients with Chronic Lymphocytic Leukemia (CLL)

Abstract Abstract 4637 Purine analogs, including fludarabine and pentostatin, are frequently used as first-line agents once therapy of CLL commences. However, as a result of such treatment, approximately 20% of patients become myelosuppressed to the extent that a full course of therapy cannot be given. Myelosuppression was defined as absolute neutrophil count We attempted to correlate CD38 and Zap-70 expression with pre-treatment risk factors (age, Rai stage, and performance status), but found no association, except in the case of CD38 positivity in relation to PS ≥ 1 (p = 0.04). Cytogenetics were unknown for a majority of patients and therefore were not analyzed. The 9 patients remained myelosuppressed for a median of 10 months (range 2 to 41), and 6 of these 9 patients were platelet transfusion dependent at some point (compared to 1 of 36 patients of the non-myelosuppressed group, p Disclosures: Kalaycio: Genzyme: Speakers Bureau; Genetech: Speakers Bureau; Cephalon: Speakers Bureau.
Dual activation of bile acid receptors FXR and TGR5 plays a protective role in non-alcoholic fatty liver disease and atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of conditions which ranges from fatty liver to non-alcoholic steatohepatitis (NASH) and liver cirrhosis. The aim of this study is to establish...
Local sharpening and subspace wavefront correction with predictive dynamic digital holography

Digital holography holds several advantages over conventional imaging and wavefront sensing, chief among these being significantly fewer and simpler optical components and the retrieval of complex field. Consequently, many imaging and sensing applications including microscopy and optical tweezing have turned to using digital holography. A significant obstacle for digital holography in real-time applications, such as wavefront sensing for high energy laser systems and high speed imaging for target racking, is the fact that digital holography is computationally intensive; it requires iterative virtual wavefront propagation and hill-climbing to optimize some sharpness criteria. It has been shown recently that minimum-variance wavefront prediction can be integrated with digital holography and image sharpening to reduce significantly large number of costly sharpening iterations required to achieve near-optimal wavefront correction. This paper demonstrates further gains in computational efficiency with localized sharpening in conjunction with predictive dynamic digital holography for real-time applications. The method optimizes sharpness of local regions in a detector plane by parallel independent wavefront correction on reduced-dimension subspaces of the complex field in a spectral plane.
Lemur Use of Hands Versus Mouth

Several hypotheses have been offered to explain handedness in primates. In prosimian primates, including lemurs, left-hand orientation has been demonstrated; however, few studies have examined hand vs. mouth orientation. We compared preference for use of hand vs. mouth, single hand over both hands, and right hand vs. left hand in captive ring-tailed lemurs (Lemur catta), black-and-white ruffed lemurs (Varecia variegata), and collared brown lemurs (Eulemur collaris). For a male and female of each species, plus twin female offspring of ring-tailed lemurs, we made 100 observations per individual, recording hand vs. mouth use every 30 seconds as individuals performed enrichment and routine daily activities. Overall, these lemurs tended to be more handed than mouth-oriented, preferred to use a single hand more than both hands, and used their left hand more than their right. Males were more left-handed than females. Analysis of specific activities showed that eating was hand-oriented, while grooming was mouth-oriented. Results are also reported by species. Research on lemur use of hands vs. mouth could provide insight into the evolution of handedness in primates.
Evaluation of Linguistic Markers of Word-Finding Difficulty and Cognition in Parkinson's Disease

Purpose Early cognitive symptoms such as word-finding difficulty (WFD) in daily conversation are common in Parkinson's disease (PD), but studies have been limited by a lack of feasible, quantitativ...
Nuclear-matter calculations using theΛ00 andΛ10 theories

The ground-state properties of nuclear matter are calculated using theΛ00 andΛ10 approximations. A nucleon-nucleon interaction was chosen to be the same as that used by Wegman and Weigel in aΛ11 calculation.
PSYCHOSOCIAL FACTORS IN INFLAMMATORY BOWEL DISEASE

From the case example, it can be seen that when the physician considered the psychosocial aspects of the disease in the treatment of Ms. B, she was able to make a complete recovery, something the medications themselves had been unable to do. Although originally thought to be a purely psychosomatic illness, research in IBD in the past three decades has shown that psychosocial aspects are an important component of IBD, but they are not the cause of the disease. Several studies have indicated that stress can adversely affect the gastrointestinal tract directly, by altering inflammatory mediators and gastrointestinal neurotransmitters. To get a complete clinical assessment of how a patient is functioning with the disease, it is important to incorporate psychosocial information into daily patient care in addition to laboratory measurements of disease severity. How does one obtain the psychosocial information for an individual patient? An understanding of the positive and negative factors that may influence how a patient adapts to chronic illness is important, including the patient's social support system, the self-confidence of the patient, and the presence of any comorbid psychiatric disease. In addition, HRQOL can help the clinician identify areas that may be of concern to large groups of patients with the same disease. By incorporating information obtained through HRQOL and modifying it to the psychosocial situation of the individual patient, the treatment plan becomes a negotiated agreement between the physician and the patient. These steps may lead to increased compliance, decreased likelihood of misunderstanding between the physician and the patient, and improvement in the health status of patients with IBD.
Stimuli, the Perceiver, and Perception

Virtually every boy who has grown up in a cold climate has had the experience of warming his hands after making snowballs by holding them in water from the cold water tap. Nearly everyone who has been ill with a high fever has noted how cool the hand of the examining physician or nurse feels. And certainly everybody has observed that a flashlight which shines brightly at night will appear dim during daylight, if indeed it is seen at all. These experiences are examples of successive thermal contrast and simultaneous brightness contrast, two of the phenomena with which this chapter is concerned. They illustrate the very important fact that the appearance of a stimulus (the water, the hand, the light) depends not only on its physical intensity but also on the intensity of its immediately surrounding area as well as on that of stimuli immediately previously experienced. As the cold hand approaches the temperature of the tap water, the tap water will cease to feel warm. When it equals that of the tap water no temperature sensation will be experienced at all. And if the hand is further warmed by being placed in water from the hot water tap, water from the cold water tap will then feel cold. These changes in experience illustrate two important psychological principles, namely that perception is relative and depends on some psychological referent or base line and that these psychological base lines change with experience over time.
Comparison of effects of antimicrobial interventions on multidrug-resistant Salmonella, susceptible Salmonella, and Escherichia coli O157:H7.

Several strains of Salmonella have been identified as resistant to multiple antibiotics. What is not known is whether strains possessing multidrug resistance properties also have the ability to resist the killing effects of the antimicrobial interventions used in beef processing. The research project described herein was designed to determine whether antimicrobial interventions currently in place in beef processing facilities are adequate for reducing the foodborne pathogen loads on beef carcass surfaces contaminated with multidrug-resistant (MDR) Salmonella. The data presented here indicate that MDR Salmonella is reduced at least as effectively as are Escherichia coli O157:H7 and susceptible Salmonella when treated with antimicrobial interventions currently in use at most U.S. beef processing plants. The E. coli O157:H7 strains used in this study were divided into two groups, strains that have a genetic polymorphism associated with human disease and strains not typically found to cause human disease. No ...
Social Networks as Vital Resources for Adults' Learning

It is clear that, when researched and analyzed critically, social networks provide a ubiquitous and powerful tool to provide insight into current and past societal trends and perspectives. This paper provides a model for thinking about and implementing social networks for organizations which function in and serve across virtual spaces. From distance learning to e-commerce, b-learning and corporate training to informal learning, sports and entertainment industries, social media is a powerful context for dialogue, expression and lived experience. How well prepared are our organizations to understand current trends and perspectives in virtual spaces? Where do we begin? What skills do employees and students need to analyze critically the data gathered from social media and other virtual spaces? This paper presents specific strategies, valuable recommendations, and further direction for social networks’ use in these areas.
Hidden disorder in the α'→δ transformation of Pu-1.9 at.% Ga

Enthalpy and entropy are thermodynamic quantities critical to determining how and at what temperature a phase transition occurs. At a phase transition, the enthalpy and temperature-weighted entropy differences between two phases are equal ($\ensuremath{\Delta}H=T\ensuremath{\Delta}S$), but there are materials where this balance has not been experimentally or theoretically realized, leading to the idea of hidden order and disorder. In a Pu-1.9 at. $%$ Ga alloy, the $\ensuremath{\delta}$ phase is retained as a metastable state at room temperature, but at low temperatures, the $\ensuremath{\delta}$ phase yields to a mixed-phase microstructure of $\ensuremath{\delta}$- and ${\ensuremath{\alpha}}^{\ensuremath{'}}$-Pu. The previously measured sources of entropy associated with the ${\ensuremath{\alpha}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\delta}$ transformation fail to sum to the entropy predicted theoretically. We report an experimental measurement of the entropy of the ${\ensuremath{\alpha}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\delta}$ transformation that corroborates the theoretical prediction, and implies that only about 65$%$ of the entropy stabilizing the $\ensuremath{\delta}$ phase is accounted for, leaving a missing entropy of about 0.5 ${k}_{B}$/atom. Some previously proposed mechanisms for generating entropy are discussed, but none seem capable of providing the necessary disorder to stabilize the $\ensuremath{\delta}$ phase. This hidden disorder represents multiple accessible states per atom within the $\ensuremath{\delta}$ phase of Pu that may not be included in our current understanding of the properties and phase stability of $\ensuremath{\delta}$-Pu.
CNS Complications of Frontal Sinus Disease

Although less common since the advent of antibiotics, CNS complications of frontal sinusitis still occur and warrant a high index of suspicion to permit timely diagnosis and management.
Drug Addiction: Mechanisms of Nicotine Dependence Unmasked by Gene Editing.

Summary New gene editing technologies are enabling exploration of previously intractable features of genetic risk for drug addiction. A recent study using this technology reveals new insights into how a mutation linked to tobacco dependence influences the addictive properties of nicotine.
Primum non nocere : robots and spinal surgery

In this article, Lieber et al . performed a retrospective analysis of data in the Nationwide Inpatient Sample database, comparing 257 patients who underwent robot-assisted lumbar fusion with 257 matched controls who underwent conventional lumbar fusion. After controlling for various patient factors, they did not find a significant difference in minor or major complications between the two groups. However, they report increased hospital costs and length of stay in the robot-assisted group, compared with the conventional lumbar fusion group.
Perception, knowledge, and interest of urologic surgery: a medical student survey

Although only a limited number of medical schools require a formal educational rotation in urologic surgery, urology as a medical specialty continues to attract a large number of students into the match each year. The purpose of this study was to describe medical student awareness, perception, and knowledge of urology, to determine factors influencing students’ consideration of urology as a career, and to determine if prior urology clerkship experience is associated with differences in these variables. In this cross-sectional study, medical students were electronically surveyed in 07/2016. Self-reported and question-based knowledge of urology were determined. A total of 25 factors were assessed with a five-point Likert scale to determine their influence on students’ consideration of urology as a career. Data analysis was performed using R. The survey was completed by 114 students (13.5% of all medical students). A total of 11(9.65%)students had previously participated in a urology clerkship. All students reported awareness of urology; however, only 74 students (64.9%) correctly identified the training pathway and job duties of urologists. Self-perceived knowledge of urology was poor but improved with increased medical school training. Question-based assessment also demonstrated increased knowledge with advanced medical school training (27% per year; p < 0.01). Prior urology clerkship experience appeared to be associated with increased urologic knowledge; however, this was confounded by year in medical school training. When assessing factors impacting students’ consideration of a career in urology, ‘combination of medicine and surgery’ was the most positively influential and ‘competitiveness of the specialty’ was the most negatively influential. Although medical students are aware of urology as a specialty, they perceive their knowledge of urology as poor. However, knowledge of urology increases throughout medical school training. Multiple factors influence students’ consideration of urology as a career choice. Additional studies are needed to further explore how participation in a formal urology experience alters students’ perceptions and influences their consideration of urology as a career choice. Retrospectively registered.
Assessing preference and survival of Danaus plexippus on two western species of Asclepias

Monarch butterfly (Danaus plexippus L.) migratory populations in North America have declined over the last 20 years. Milkweed (Asclepias, Apocynaceae) is the primary larval host plant for monarchs. The primary conservation strategy for monarchs has been to build habitat, with a focus on milkweed seeds and plugs. However, not all milkweed may offer the same benefits for monarch conservation, as monarchs may prefer some taxa over others, or taxa may vary in the nutrients and protective toxins they provide. Comparisons of milkweed suitability have been made for milkweed taxa in the midwestern and eastern United States (U.S.), but very little is known about milkweeds found in the southwestern U.S. We tested female egg-laying preferences and larval performance in captivity on two species of milkweed commonly available for habitat plantings in the Southwest: Arizona milkweed (Asclepias angustifolia Schweig.) and pineneedle milkweed (A. linaria Cav.). We tested four measures of larval performance: survival, duration, mass and adult forewing length. Monarchs were more likely to lay eggs on Arizona milkweed than pineneedle milkweed. Larvae had a higher survival rate and grew more rapidly on Arizona milkweed, and adults from larvae raised on Arizona milkweed were larger than those raised on pineneedle milkweed. In the field, monarch caterpillars were more likely to be found on Arizona milkweed. We recommend Arizona milkweed for monarch habitat conservation projects in the Southwest within the natural range of Arizona milkweed, but that D. plexippus preference and performance be tested for additional western milkweed species.
Terrestrial Evaporation and Moisture Drainage in a Warmer Climate

To determine hydrologic changes in a warmer climate, we impose precipitation and potential evaporation perturbations on hydrologic response functions constructed from precipitation and satellite so...
Lipid availability influences the metabolic maturation of human pluripotent stem cell-derived cardiomyocytes

Abstract Objectives Pluripotent stem cell-derived cardiomyocytes are phenotypically immature, which limits their utility in downstream applications. Metabolism is dramatically reprogramed during cardiac maturation in vivo and presents a potential avenue to drive in vitro maturation. We aimed to identify and address metabolic bottlenecks in the generation of human pluripotent stem cell (hPSC)-derived cardiomyocytes. Methods hPSCs were differentiated into cardiomyocytes using an established, chemically-defined differentiation protocol. We applied 13C metabolic flux analysis (MFA) and targeted transcriptomics to characterize cardiomyocyte metabolism in during differentiation in the presence or absence of exogenous lipids. Results hPSC-derived cardiomyocytes induced some cardiometabolic pathways (i.e. ketone body and branched-chain amino acid oxidation) but failed to effectively activate fatty acid oxidation. MFA studies indicated that lipid availability in cultures became limited during differentiation, suggesting potential issues with nutrient availability. Exogenous supplementation of lipids improved cardiomyocyte morphology, mitochondrial function, and promoted increased fatty acid oxidation in hPSC-derivatives. Conclusion hPSC-derived cardiomyocytes are dependent upon exogenous sources of lipids for metabolic maturation. Proper supplementation removes a potential roadblock in the generation of metabolically mature cardiomyocytes. These studies further highlight the importance of considering and exploiting metabolic phenotypes in the in vitro production and utilization of functional hPSC-derivatives.
A Markov Mixed-Effect Multinomial Logistic Regression Model for Nominal Repeated Measures with an Application to Syntactic Self-Priming Effects.

Syntactic priming effects have been investigated for several decades in psycholinguistics and the cognitive sciences to understand the cognitive mechanisms that support language production and comp...
Angiography During Cardiovascular Surgery

Intraoperative fluorescence imaging (IFI) is currently indicated as a tool to determine the patency of coronary artery bypass grafts. Graft patency is the major determinant of survival and freedom from repeat intervention after coronary artery bypass grafting (CABG) (Desai et al. J Am Coll Cardiol 46;1521–1525, 2005). Unfortunately, early graft failure after coronary artery bypass grafting is common. The PREVENT IV study revealed that at 1 year up to 26% of coronary bypass grafts will be closed (PREVENT IV Investigators. JAMA 294:2446–2454, 2005). Interestingly, the 30-day mortality outcomes were excellent in the trial (PREVENT IV Investigators. JAMA 294:2446–2454, 2005). However, the subgroup with graft failure had twice the rate of perioperative myocardial infarction (MI) and four times the risk of death, MI, and need for revascularization at 1 year. Significant advances in medical therapy including early postoperative aspirin administration, statin use, and increased use of arterial grafting have improved early and late graft patency (Taggart DP. J Thorac Cardiovasc Surg 120:651–659, 2000; Yusuf et al. Lancet 344;563–570, 1994; Lytle et al. J Thorac Cardiovasc Surg 117:855, 1999; Taggart et al. Lancet 358:870–875, 2001). However, technical errors in bypass graft construction by the operating surgeon are primarily responsible for the majority of these early failures (Puskas et al. JAMA 291:1841–1849, 2004; Khan et al. N Engl J Med 350:21–28, 2004). With the exception of coronary artery bypass surgery, virtually all other interventions on the heart, including cardiac valve repair/replacement and coronary stenting, are accompanied by completion diagnostic imaging to ensure an adequate technical result. Despite tremendous improvements in the quality of processes of care in cardiac surgery over the past decade, there are still no well-accepted or broadly used techniques to assess the quality of the bypass graft itself. Recent angiographic trials by Puskas et al. (JAMA 291:1841–1849, 2004) and Khan et al. (N Engl J Med 350:21–28, 2004) have shown significant clustering of the technical results of off-pump surgery at the level of the individual surgeon, highlighting the need for intraoperative quality assurance. Since graft patency is the predominant predictor of long-term survival after coronary surgery, a well-validated method to assess graft patency in coronary surgery remains an important opportunity for improving quality assurance (Lytle et al. J Thorac Cardiovasc Surg 103(5):831–840, 1992; Halabi et al. Am J Cardiol 96:1254–1259, 2005). We will discuss the use of intraoperative fluorescence imaging as a method of assessing real-time coronary artery bypass grafts as well as the quantification of improved myocardial blood flow. We will also discuss the other currently available methods of assessing early graft patency and compare them to intraoperative fluorescence imaging.
Five enzymes of the Arg/N-degron pathway form a targeting complex: The concept of superchanneling.

The Arg/N-degron pathway targets proteins for degradation by recognizing their N-terminal (Nt) residues. If a substrate bears, for example, Nt-Asn, its targeting involves deamidation of Nt-Asn, arginylation of resulting Nt-Asp, binding of resulting (conjugated) Nt-Arg to the UBR1-RAD6 E3-E2 ubiquitin ligase, ligase-mediated synthesis of a substrate-linked polyubiquitin chain, its capture by the proteasome, and substrate’s degradation. We discovered that the human Nt-Asn–specific Nt-amidase NTAN1, Nt-Gln–specific Nt-amidase NTAQ1, arginyltransferase ATE1, and the ubiquitin ligase UBR1-UBE2A/B (or UBR2-UBE2A/B) form a complex in which NTAN1 Nt-amidase binds to NTAQ1, ATE1, and UBR1/UBR2. In addition, NTAQ1 Nt-amidase and ATE1 arginyltransferase also bind to UBR1/UBR2. In the yeast Saccharomyces cerevisiae, the Nt-amidase, arginyltransferase, and the double-E3 ubiquitin ligase UBR1-RAD6/UFD4-UBC4/5 are shown to form an analogous targeting complex. These complexes may enable substrate channeling, in which a substrate bearing, for example, Nt-Asn, would be captured by a complex-bound Nt-amidase, followed by sequential Nt modifications of the substrate and its polyubiquitylation at an internal Lys residue without substrate’s dissociation into the bulk solution. At least in yeast, the UBR1/UFD4 ubiquitin ligase interacts with the 26S proteasome, suggesting an even larger Arg/N-degron–targeting complex that contains the proteasome as well. In addition, specific features of protein-sized Arg/N-degron substrates, including their partly sequential and partly nonsequential enzymatic modifications, led us to a verifiable concept termed “superchanneling.” In superchanneling, the synthesis of a substrate-linked poly-Ub chain can occur not only after a substrate’s sequential Nt modifications, but also before them, through a skipping of either some or all of these modifications within a targeting complex.
Changes in Health Status in the Ft. Devens Gulf War Veterans Cohort: 1997-2017.

Gulf War veterans (GWVs) were exposed to numerous neurotoxicants during deployment. Upon returning home, many reported a multitude of symptoms including fatigue, pain, gastrointestinal and respirat...
The Value of Inter-Regional Coordination and Transmission in Decarbonizing the US Electricity System

Summary Preventing global warming in excess of 1.5°C–2°C requires a transition to zero-carbon electricity systems by midcentury along with the widespread electrification of other sectors. Current state-level renewable portfolio standards and regional transmission arrangements do not capture the benefits of inter-regional transmission or coordination of planning and dispatch for renewable-energy integration. Here, using a co-optimized capacity-planning and dispatch model over 7 years of hourly operation, we show that inter-state coordination and transmission expansion reduce the system cost of electricity in a 100%-renewable US power system by 46% compared with a state-by-state approach, from 135 $/MWh to 73 $/MWh. Sensitivity analyses show that reductions in the cost of photovoltaics, wind, and lithium-ion batteries lead to the lowest electricity costs for systems in which transmission expansion is allowed, while cost reductions for nuclear power or long-duration energy storage lead to greater electricity cost reductions for isolated systems.
Comparative genomics reveals high rates of horizontal transfer and strong purifying selection on rhizobial symbiosis genes

Horizontal transfer (HT) alters the repertoire of symbiosis genes in rhizobial genomes and may play an important role in the on-going evolution of the rhizobia-legume symbiosis. To gain insight into the extent of HT of symbiosis genes with different functional roles (nodulation, N-fixation, host benefit and rhizobial fitness), we conducted comparative genomic and selection analyses of the full-genome sequences from 27 rhizobial genomes. We find that symbiosis genes experience high rates of HT among rhizobial lineages but also bear signatures of purifying selection (low Ka : Ks). HT and purifying selection appear to be particularly strong in genes involved in initiating the symbiosis (e.g. nodulation) and in genome-wide association candidates for mediating benefits provided to the host. These patterns are consistent with rhizobia adapting to the host environment through the loss and gain of symbiosis genes, but not with host-imposed positive selection driving divergence of symbiosis genes through recurring bouts of positive selection.