cssi/SciSciGPT-SciSciNet huggingface dataset:
Copper Interconnects: Surface State Engineering to Facilitate Specular Electron Scattering

In situ electron transport measurements on epitaxial 10-nm-thick Cu(001) with Al and AlO x cap layers indicate that the electron surface scattering specularity increases when the density of electronic surface states decreases. The Cu layers were sputter deposited on MgO(001) substrates, and their resistance is measured in situ as a function of the Al cap thickness ${d}_{\text {Al}} = {0}\!-\!{1.4}$ nm as well as oxygen exposure from $10^{-{1}}$ to $10^{{5}}$ Pa $\cdot \text{s}$ . The resistance increases with increasing ${d}_{\text {Al}}$ , indicating a decrease in the surface scattering specularity that is well described by an exponential decay, attributed to the linearly increasing number of localized surface states available for electron scattering. In contrast, exposure to 0.04–50 Pa O2 results in a decrease in the measured resistance, as the Al cap is oxidized to form AlO x , leading to a decreasing surface density of states and increasing scattering specularity with increasing ${x}$ . The conductance enhancement is most pronounced for ${d}_{\text {Al}} = {0.4}$ nm since a larger ${d}_{\text {Al}}$ leads to incomplete Al oxidation, while a smaller ${d}_{\text {Al}}$ insufficiently suppresses copper surface oxidation, causing a transition to diffuse surface scattering. The overall results indicate that insulating liner layers provide a conductance advantage for narrow interconnect lines.
Cleaning and Sterilization of Dental Instruments

All health-care professionals are responsible for maintenance and ensuring sterility of instruments used in medical care. The dental profession is no exception to this rule, and all staff and dentists are responsible for preventing infection control breaches in the operatory. Previous case reports have demonstrated that disease is transmissible from dental equipment to patients, making the cleaning and sterilization of dental instruments a top priority. In this chapter, we review the basic definitions used when describing cleaning and sterilization processes, as well as CDC classifications for instruments. We discuss the six major steps in instrument processing required to ensure dental equipment is processed efficiently and safely. Finally, we examine different sterility indicators and their use in quality assurance of proper sterilization.
Revision Multiligament Knee Reconstruction Surgery

Failed multiligament knee reconstruction is a challenging problem due to recurrent pathologic laxity that is often associated with limb malalignment, meniscus deficiency, articular cartilage insufficiency, decreased motion, compromised bone stock, and a paucity of graft sources. Revision surgical indications and techniques require a comprehensive evaluation of the patient, injury and treatment factors along with a focused physical examination and advanced imaging. A stepwise treatment approach can be effective in the evaluation of revision surgery and also in setting realistic patient goals.
Translational studies of intravenous and intracerebroventricular routes of administration for CNS cellular biodistribution for BMN 250, an enzyme replacement therapy for the treatment of Sanfilippo type B

BMN 250 is being developed as enzyme replacement therapy for Sanfilippo type B, a primarily neurological rare disease, in which patients have deficient lysosomal alpha-N-acetylglucosaminidase (NAGLU) enzyme activity. BMN 250 is taken up in target cells by the cation-independent mannose 6-phosphate receptor (CI-MPR, insulin-like growth factor 2 receptor), which then facilitates transit to the lysosome. BMN 250 is dosed directly into the central nervous system via the intracerebroventricular (ICV) route, and the objective of this work was to compare systemic intravenous (IV) and ICV delivery of BMN 250 to confirm the value of ICV dosing. We first assess the ability of enzyme to cross a potentially compromised blood-brain barrier in the Naglu-/- mouse model and then assess the potential for CI-MPR to be employed for receptor-mediated transport across the blood-brain barrier. In wild-type and Naglu-/- mice, CI-MPR expression in brain vasculature is high during the neonatal period but virtually absent by adolescence. In contrast, CI-MPR remains expressed through adolescence in non-affected non-human primate and human brain vasculature. Combined results from IV administration of BMN 250 in Naglu-/- mice and IV and ICV administration in healthy juvenile non-human primates suggest a limitation to therapeutic benefit from IV administration because enzyme distribution is restricted to brain vascular endothelial cells: enzyme does not reach target neuronal cells following IV administration, and pharmacological response following IV administration is likely restricted to clearance of substrate in endothelial cells. In contrast, ICV administration enables central nervous system enzyme replacement with biodistribution to target cells.
Hypertension Management in Nursing Homes: Review of Evidence and Considerations for Care

We sought to summarize recent evidence regarding optimal blood pressure (BP) treatment targets and antihypertensive regimen intensity for nursing home (NH) residents and similar older, complex patients with hypertension. Recent trials have demonstrated cardiovascular benefits from more intensive BP targets among ambulatory, less complex older adults, but generalizability to NH residents is questionable. Other trials have demonstrated that de-intensifying antihypertensives in frail, older patients is feasible, with no or modest increases in BP, but most have not assessed effects on patient-centered outcomes. Observational studies with patients more representative of NH residents suggest harms associated with more intensive BP treatment and reduction in fall risk associated with deintensification, but findings and potential for bias vary across studies. Randomized trials and rigorous observational studies examining effects of deintensified BP management on patient-centered outcomes in complex, older populations are needed to inform improved guidelines and treatment for NH residents.
¿Solamente o solamento?: desafíos en el aprendizaje de forma y significado de -mente y -miento/-mento por hablantes de ele

espanolEste estudio se aproxima a las dificultades mas frecuentes que enfrentan los estudiantes de espanol como L2 (EL2) en la adquisicion del significado y forma de los sufijos -mente y -miento/-mento. En el Corpus de Aprendices de Espanol (CAES), se localizan palabras derivadas con estos sufijos, y se codifican errores formales y semanticos que indiquen si los aprendices utilizan las palabras de memoria o las descomponen. Los errores semanticos son limitados y se ajustan a palabras especificas. Tampoco destacan errores sintacticos en la asignacion de la categoria gramatical de la palabra. Los errores ortograficos y morfologicos son los mas frecuentes. Conforme al modelo de Jiang (2000), los aprendices parecen unir primero la forma de toda la palabra con el significado en la L1. Tras esta etapa, descomponen la palabra, lo que se refleja en sus errores ortograficos y morfologicos. Estos errores indicarian que el sufijo se guarda como un elemento de la L2 en el lexicon. Con los ejemplos analizados, se ofrece una serie de palabras prototipicas para que los aprendices de EL2 reflexionen sobre estos sufijos. EnglishThis corpus-based study addresses the most frequent difficulties that Spanish L2 learners show in the acquisition of meaning and of the frequent suffixes -mente and -miento/-mento. In the Corpus de Aprendices de Espanol (CAES), derived words with these suffixes were searched. Meaning-based and formal errors were coded to show whether learners were using whole word memorization or whether they were decomposing words. Meaning-based errors were limited and related to specific words. Syntactic errors were also scarce. Orthographic and morphological errors were the most frequent. According to Jiang’s (2000) model, learners seem to make connections between the L2 word form and the L1 meaning. After this phase, learners start decomposing the word, which is reflected in their orthographic and morphological errors. These errors point out that the suffix is stored in the L2 lexicon. Based on the examples analyzed, some prototypical words are recommended for awareness raising activities so that Spanish L2 learners recognize suffix’ characteristics and their learning challenges.
Potential High-Performance Magnet: Fe - and Zr -Alloyed Ce 2 Co 17

By performing comprehensive first-principles calculations, we study the hard magnetic properties of ${\mathrm{Ce}}_{2}$${\mathrm{Co}}_{17}$ and ${\mathrm{Ce}}_{2}$${\mathrm{Fe}}_{17}$ under $\mathrm{Zr}$ doping with varying $\mathrm{Co}$ concentrations, given the substantial experimental success of $\mathrm{Zr}$ in improving the magnetic anisotropy energy (MAE) in ${\mathrm{Ce}}_{2}$${\mathrm{Co}}_{17}$ and ${\mathrm{Sm}}_{2}$${\mathrm{Co}}_{17}$. We find that the magnetic properties of these alloys become comparable to state-of-the-art magnetic materials by doping with two elements, $\mathrm{Zr}$ and $\mathrm{Fe}$, with potential-energy products $B{H}_{max}$ of 40 MG Oe. The $\mathrm{Zr}$ substitution is particularly helpful for improving the MAE, leading to a magnetic hardness parameter ${K}_{1}/{\ensuremath{\mu}}_{0}{M}_{s}^{2}$ that significantly exceeds unity for a substantial range of $\mathrm{Co}$ concentrations (between 60% and 100% of the $3d$-element concentration). The calculated MAE exhibits a strong dependence on the $\mathrm{Co}$ concentration, indicative of a likely valence fluctuation with $\mathrm{Co}$ alloying, and shows a maximum value of 7.78 ${\mathrm{MJ}/\mathrm{m}}^{3}$ for 60% $\mathrm{Co}$ doping. Thus, upon experimental verification, these alloys may become competitors to the better-known permanent-magnet materials ${\mathrm{Nd}}_{2}$${\mathrm{Fe}}_{14}$$\mathrm{B}$ and ${\mathrm{Sm}\mathrm{Co}}_{5}$.
Decreased Amygdalar Activation to NSSI-Stimuli in People Who Engage in NSSI: A Neuroimaging Pilot Study

In healthy individuals, stimuli associated with injury (such as those depicting blood or wounds) tend to evoke negative responses on both self-report and psychophysiological measures. Such an instinctive aversion makes sense from an evolutionary perspective. However, to engage in nonsuicidal self-injury (NSSI), this natural barrier must be overcome. The Benefits and Barriers model of NSSI predicts that people who engage in NSSI will show diminished aversion to NSSI-related stimuli compared to controls who do not engage in NSSI. We tested this hypothesis in a pilot study assessing 30 adults, 15 of whom reported current skin cutting and 15 of whom had no history of NSSI. Functional magnetic resonance imaging (fMRI) data were collected while participants viewed neutral, positive, and negative images selected from the International Affective Picture System. Participants also viewed NSSI images depicting razors, scalpels, or wounds caused by cutting. Compared to healthy control (HC) participants, the NSSI group showed decreased amygdala and increased cingulate cortex (CC) and orbitofrontal cortex (OFC) activation to NSSI and negative images. They also showed increased amygdalar and OFC activation to positive images. Neither the control group nor the NSSI group demonstrated significant activation within regions more typically associated with reward during any of the conditions; however, positive and negative affect ratings collected throughout the course of the task suggested that none of the affective conditions were viewed as rewarding. Although preliminary, these findings are suggestive of reduced limbic and greater cortical processing of NSSI stimuli in those with a history of this behavior. This has potentially important implications for current models of NSSI as well as for its treatment.
Carpal Morphology and Function in the Earliest Cetaceans

During the land-to-water transition in the Eocene epoch, the cetacean skeleton underwent modifications to accommodate life in the seas. These changes are well-documented in the fossil record. The f...
Elevated Extracellular cGMP Produced after Exposure to Enterotoxigenic Escherichia coli Heat-Stable Toxin Induces Epithelial IL-33 Release and Alters Intestinal Immunity

Enterotoxigenic Escherichia coli (ETEC) is a major diarrheal pathogen in children in low- to middle-income countries. Previous studies identify heat-stable enterotoxin (ST)-producing ETEC as a prevalent diarrheal pathogen in children younger than five. While many studies have evaluated the interaction of ETEC heat-labile enterotoxin (LT) with host epithelium and immunity, few investigations have attempted similar studies with ST. To further understand ST pathogenesis, we examined the impact of ST on cGMP localization, epithelial cell cytokine production, and antibody development following immunization. In addition to robust intracellular cGMP in T84 cells in the presence of phosphodiesterase inhibitors (PDEis) that prevent the breakdown of cyclic nucleotides, we found that prolonged ST intoxication induces extracellular cGMP accumulation in the presence or absence of PDEis. Further, ST intoxication induces luminal cGMP in vivo in mice, suggesting that secreted cGMP may have other cellular functions. Using RNAseq and qPCR, we demonstrate that ST intoxication, or treatment with the clinically-used ST-mimic linaclotide, alters inflammatory cytokine gene expression, including IL1-family member IL-33, which can also be induced by cell-permeable 8-Br-cGMP. Finally, when present during immunization, ST suppresses antibody induction to specific antigens. In conclusion, our studies indicate that ST modulates epithelial cell physiology and the interplay between the epithelial and immune compartments.
Plant-Human Embodied Biofeedback (pheB): A Soft Robotic Surface for Emotion Regulation in Confined Physical Space

“pheB,” is a robotic “plant-human, embodied, biofeedback” system to support the wellbeing of human inhabitants in confined, physical spaces. This surface aims to increase users’ emotion regulation and foster connections with nature by visualizing the internal states of plants through tactile, expressive movement. Unlike 2D biofeedback visualization models currently in use, our research explores mindfulness practices through immersive, tangible interactions to increase therapeutic effectiveness. This pictorial traces the development of our design (to-date) and presents results from an early user study conducted to (a) assess the prototype at leading breathing exercises, (b) evaluate preferences for different design features, and (c) refine the design of a questionnaire for future user testing. Findings suggest pheB was perceived positively and as an embodied extension of self during guided breathing exercises. This work contributes knowledge toward developing novel biofeedback modalities and offers a design exemplar for interactive artifacts that nurture meaningful relationships with nature.
H-TD²: Hybrid Temporal Difference Learning for Adaptive Urban Taxi Dispatch

We present H-TD²: Hybrid Temporal Difference Learning for Taxi Dispatch, a model-free, adaptive decision-making algorithm to coordinate a large fleet of automated taxis in a dynamic urban environment to minimize expected customer waiting times. Our scalable algorithm exploits the natural transportation network company topology by switching between two behaviors: distributed temporal-difference learning computed locally at each taxi and infrequent centralized Bellman updates computed at the dispatch center. We derive a regret bound and design the trigger condition between the two behaviors to explicitly control the trade-off between computational complexity and the individual taxi policy's bounded sub-optimality; this advances the state of the art by enabling distributed operation with bounded-suboptimality. Additionally, unlike recent reinforcement learning dispatch methods, this policy estimation is adaptive and robust to out-of-training domain events. This result is enabled by a two-step modelling approach: the policy is learned on an agent-agnostic, cell-based Markov Decision Process and individual taxis are coordinated using the learned policy in a distributed game-theoretic task assignment. We validate our algorithm against a receding horizon control baseline in a Gridworld environment with a simulated customer dataset, where the proposed solution decreases average customer waiting time by 50% over a wide range of parameters. We also validate in a Chicago city environment with real customer requests from the Chicago taxi public dataset where the proposed solution decreases average customer waiting time by 26% over irregular customer distributions during a 2016 Major League Baseball World Series game.
The Principle of Fairness and States’ Duty to Obey International Law

I employ the principle of fairness to argue that many existing states have a moral duty to obey international law simply in virtue of its status as law. On this voluntarist interpretation of the principle of fairness, agents must accept (in a technical sense) the benefits of a cooperative scheme in order to acquire an obligation to contribute to that scheme’s operation. I contend that states can accept the benefits international law provides, and that only if they do so do states have a fair-play duty to obey international law. In addition, I demonstrate that A. John Simmons’ criticisms of the attempt to use the principle of fairness to establish a duty to obey domestic law – both with respect to understanding the legal order as a cooperative scheme, and to agents’ acceptance of benefits – do not apply in the international context.
Gastroesophageal reflux and altered motility in lung transplant rejection

Background Lung transplantation has become an effective therapeutic option for selected patients with end stage lung disease. Long-term survival is limited by chronic rejection manifest as bronchiolitis obliterans syndrome (BOS). The aspiration of gastric contents has been implicated as a causative or additive factor leading to BOS. Gastroesophageal reflux (GER) and altered foregut motility are common both before and after lung transplantation. Further, the normal defense mechanisms against reflux are impaired in the allograft. Recent studies using biomarkers of aspiration have added to previous association studies to provide a growing body of evidence supporting the link between rejection and GER. Further, the addition of high-resolution manometry (HRM) and impedance technology to characterize bolus transit and the presence and extent of reflux regardless of pH might better identify at-risk patients. Although additional prospective studies are needed, fundoplication appears useful in the prevention or treatment of post-transplant BOS. Purpose This review will highlight the existing literature on the relationship of gastroesophageal reflux and altered motility to lung transplant rejection, particularly BOS. The article will conclude with a discussion of the evaluation and management of patients undergoing lung transplantation at our center.
Tumour necrosis factor-alpha- vs. growth factor deprivation-promoted cell death: distinct converging pathways.

Perturbations of neuronal physiological homeostasis are likely to underscore neuronal demise/impairments that are reportedly associated with aging of the central nervous system and age-related neurodegenerative diseases such as Alzheimer's disease (AD). A number of age- and/or disease-associated neurotoxic events has been described. These include abnormally modified proteins such as beta amyloid and hyper-phosphorylated Tau, cytokines such as tumour necrosis factor-alpha (TNFalpha), high levels of free radicals conducive to oxidative stress, and impaired/decreased neuronal trophic support by neurotrophic factors. Overall, it could be argued that toxic events in the aged brain are either active, such as those due to a direct action of cytokines, or passive, such as those due to lack of growth factor support. It is therefore conceivable that cellular responses to such diverse toxic stimuli are different, suggesting that interventions should be targeted accordingly. In order to begin answering this question, we determined in PC12 cells the time course of activity, in response to TNFalpha (active) or growth factor withdrawal (passive), of protein kinase c-zeta (PKCzeta), nuclear factor kappa B (NFkappaB), caspases 3 and 8, and poly (ADP-ribose) polymerase (PARP), key signal transduction elements associated with modulation of cell death/survival in PC12 cells. We found that the overall activity of PKCzeta, NFkappaB and caspase 8 was significantly different depending on the apoptotic initiator. The pattern of caspase 3 and PARP activity, however, was not statistically different between serum-free- and TNFalpha-induced cell death conditions. This suggests that two distinct cell responses are elicited that converge at caspase 3, which then induces downstream events involved in the execution of a common apoptotic programme. These results contribute to the aim of differentially targeting neuronal death in the aged brain (characterized by neurotrophic factor impairments) or in the diseased brain (e.g. AD, characterized by elevated levels of pro-inflammatory cytokines).
Tandem genetic duplications in phage lambda. III. The frequency of duplication mutants in two derivatives of phage lambda is independent of known recombination systems.

Abstract The rate of production of tandem duplications in phage λ has been measured in the presence and absence of known recombination systems. Two deletion phages have been used: tdel 33, a deletion derivative of a φ80-λ hybrid phage, and λ b 221, which carries a large deletion of the central portion of the λ chromosome. Both phages are int − , and tdel 33 is also red − , by virtue of their deletions. Stocks of these phages can be prepared free of long tandem duplication derivatives by CsCl density gradient purification. After a single cycle of lytic growth, lysates from these purified phage stocks contain tandem duplications at a frequency of 10 −3 in the case of tdel 33 and 10 −5 in the case of λ b 221. These frequencies are unaffected by the presence of mutations in the host Rec system or the phage Red system. To investigate the difference in duplication frequency between tdel 33 and λ b 221, the phages were grown in mixed infection. The result indicates that a trans -active product of tdel 33 is responsible for its high frequency of duplication production. Tandem duplications have been detected by banding the phage lysates in CsCl density gradients. Long DNA addition mutants can be detected in this way if they arise with a frequency of at least 10 −5 and if the duplication length is at least 0.14 λ lengths. To accomplish this it is necessary to distinguish them from contaminating parental phage and from dense phages with aberrant structures which arise at roughly comparable frequencies. The former can be done by rebanding and the latter by growth and rebanding. To distinguish these types we have also made use of a new mutant of Escherichia coli which does not plate λ deletion phages. All of the DNA addition mutants we have detected in this way are tandem duplications; evidently mutants with long insertions arise more rarely.
Fairness in overloaded parallel queues

Maximizing throughput for heterogeneous parallel server queues has received quite a bit of attention from the research community and the stability region for such systems is well understood. However, many real-world systems have periods where they are temporarily overloaded. Under such scenarios, the unstable queues often starve limited resources. This work examines what happens during periods of temporary overload. Specifically, we look at how to fairly distribute stress. We explore the dynamics of the queue workloads under the MaxWeight scheduling policy during long periods of stress and discuss how to tune this policy in order to achieve a target fairness ratio across these workloads.
Negligible Class II MHC Presentation of B Cell Receptor-Derived Peptides by High Density Resting B Cells

Resting B lymphocytes have been credited with inducing T cell tolerance to Ig-derived and monovalent self-Ags that are internalized via the B cell receptor (BCR). These conclusions are predicated upon the assumptions that resting B cells display BCR-associated peptides in class II MHC and that the cells remain quiescent during the course of experimental manipulation. To determine whether resting B cells display BCR-associated epitopes in class II MHC, we devised a sensitive assay that averted potential activation of B cells by Ag and minimized activation by prolonged culture. Ex vivo, Percoll-fractionated B cells expressing a κ transgene encoding a T cell epitope were cultured with a reactive T cell hybridoma for 12 h. Whereas low density, LPS-activated, and BCR-activated B cells elicited significant IL-2 from the T cell hybridoma, resting high density B cells did not. Parallel results were obtained with normal B cells expressing a second epitope encoded by an endogenous V H gene. Anergic B cells, which are uniformly low density, also significantly stimulated the T cell hybridoma. Finally, longer culture periods with normal B cells resulted in a higher degree of B cell activation and significant stimulation of reactive T cell hybridomas. Our results provide evidence that activation of B cells profoundly enhances the processing and presentation of BCR-associated Ags.
Right-angle slot waveguide bends with high bending efficiency

Two right-angle bends for nanoscale slot waveguides with high bending efficiency based on a corner mirror and different resonant cavities are presented, one with a triangular cavity and the other with a square cavity. Through two-dimensional parametric scanning of the position of the mirror and the dimension of the cavity, a maximum bending efficiency calculated using mode overlap integral (MOI) of 94.3% is achieved for the bend with the triangular cavity and 93.1% is achieved for the bend with the square cavity. Although they both have similar bending performance, the position of the mirror is different between the two cases.
Local composition models for fluid mixtures over a wide density range

Abstract A molecular thermodynamic model has been developed using computer simulation data in which a polar short-range attractive contribution to the free energy is treated as a correction to the long-range contribution. The effects of the unlike-pair energy and the density on the local compositions are consistent with computer simulation data. The model treats the nonpolar and polar components of the pair attraction energies in the short- and long-range terms in a new way so that the local composition effects on the free energy are not overpredicted, as in many previous models. As a result, the model has been used to correlate phase equilibria of both nonpolar and polar systems more effectively.
In Vitro Studies of the Spindle Assembly Checkpoint in Yeast

Although extremely rare, errors in chromosome segregation lead to aneuploidy, which has been linked to cancer and birth defects. Dividing cells rely on a surveillance mechanism called the spindle assembly checkpoint (SAC), which ensures that chromosomes are properly segregated during mitosis. The SAC, comprising several proteins on the mitotic kinetochore emits a diffusible ‘wait’ signal upon detection of improper and/or unattached kinetochores, delaying mitosis. Proper attachment and biorientation silences the ‘wait’ signal allowing progress through mitosis. ‘Wait’ signal silencing is thought of in two possible ways: First, the SAC responds to kinetochore-microtubule tension. Second, the SAC responds to attachment of microtubules to kinetochores, independent of tension. This attachment-tension debate is still unresolved due to the challenge of independently controlling attachment states and levels of tension on kinetochores in vivo. To help shed more light, we purified mitotic kinetochores from budding yeast with core kinetochore components, Mtw1p and Nuf2p, fluorescently labeled. We immobilized purified kinetochores onto a coverslip in our in vitro assay, and using a very sensitive Total Internal Reflection Fluorescence Microscopy system measured an Mtw1p-Nuf2p fluorescence colocalization of 34 ± 2.2%. We performed a similar experiment, immobilizing the kinetochores onto microtubules. We measured a colocalization on microtubules of 81±6.4% indicating that Nuf2p remained bound to the kinetochore upon kinetochore-microtubule attachment in vitro, as expected. We repeated this experiment for kinetochores with fluorescently labeled Mtw1p and Bub1p, a SAC component. We measured a 12 ± 3.4% Mtw1p-Bub1p colocalization when the particles were immobilized onto a coverslip and 50 ± 1.9% on microtubules. These experiments indicate that kinetochore-microtubule attachment in yeast may not be sufficient to release Bub1p. Current efforts are focused on Mad1p, a checkpoint protein that is believed to be released from kinetochores upon microtubule attachment in vivo.
Platelet membrane fluidity and treatment response in cognitively-impaired, depressed elderly: initial results.

A prospective study of response to treatment with nortriptyline was carried out in a group of 14 inpatients with mixed symptoms of depression and dementia. Platelet membrane fluidity, as reflected by the fluorescence anisotropy of DPH labeled membranes, was determined for all 14 drug-free subjects prior to treatment by staff who were blind to clinical and demographic data. Patients who exhibited worsening of their cognitive impairment exhibited “increased” platelet membrane fluidity, an abnormality found in approximately 50% of patients with Alzheimer's disease.
Specification of an algorithm design system

This paper describes an Internet based system for studying the design of algorithms and the structure of mathematical proofs. The Algorithm Design System consists of a framework for the construction and maintenance of the learning environment by a distributed group of contributors, and a set of web pages, produced by the contributors, that form the learning environment used by students of algorithm analysis and design. The framework of the system that we describe allows for the material used by students to grow dynamically in a distributed environment and provides constraints to ensure the uniformity of form and quality of content of the end product. The paper discusses both the architecture of the system and the content of the pages that it produces.
Computations of flow and heat transfer in parallel-plate fin heat exchangers on the CM-5: effects of flow unsteadiness and three-dimensionality

Abstract An accurate computational method for the calculation of flow and heat transfer in compact heat exchangers is developed and implemented on the massively parallel Connection Machine, CM-5. In this method, the unsteady Navier-Stokes and energy equations are solved. The current study shows that the inclusion of flow unsteadiness plays a very important role in the accurate prediction of heat exchanger performance quantities of interest such as the Colburn j factor and the friction factor. It is also shown that at higher Reynolds numbers, the additional effect introduced by the intrinsic three-dimensionality of the flow plays another important role in determining the overall heat exchanger performance. Therefore, the above two effects have to be taken into account in order to accurately predict heat exchanger performance.
Ideal female body shape: Role of body weight and waist-to-hip ratio

Interrelationships of female body fat distribution as measured by the waist-to-hip ratio (WHR), overall body size, perceived attractiveness, youthfulness, health, and need to lose weight were investigated. Drawings showing thin females with high WHRs and heavier females with low WHRs were presented to college-age women with low and high scores on the Restrained Eating Scale (Herman & Polivy. [1980]. Obesity [pp. 208-225]. Philadelphia: Saunders) and men who ranked figures for various attributes. Female subjects, regardless of their eating style, as well as male subjects, judged heavier female target figures with low WHRs as more attractive and healthier than thinner figures with higher WHRs. The rankings for youthfulness and need to lose weight were not systematically affected by the size of the WHR. Female subjects perceived heavier female target figures with low WHR to represent ideal female figures. Female subjects with a restrained eating style felt their own body was not similar to idealized female figures and expressed unhappiness with their body shape; this was not true of unrestrained eaters. It is proposed that female attractiveness and ideal female shape may be more influenced by WHR than overall body size.
Steroidogenic refractoriness of bovine adrenocortical cells to dibutyryl cyclic AMP

Abstract The long-term effects of dibutyryl cyclic AMP [(Bu) 2 -cAMP] on steroidogenesis in bovine adrenocortical cells maintained in primary culture were investigated. During the first 36 h, total steroid production by cells incubated with (Bu) 2 -cAMP increased progressively. Thereafter, however, there was a marked fall in steroid output. During the first 36 h adrenocortical cells incubated in the presence of (Bu) 2 -cAMP produced substantially more C 19 -steroids and 17α-hydroxylated C 21 -steroids than did cells incubated in the absence of (Bu) 2 -cAMP. By 48 h, however, such steroid secretion by cells incubated in the continued presence of (Bu) 2 -cAMP declined toward control levels. By contrast, the secretion of corticosterone and 11-deoxycorti-costerone was consistently less by cells maintained in the presence of (Bu) 2 -cAMP than by cells maintained in its absence. These results suggest that refractoriness results, at least in part, from events which occur distal to the formation of cAMP. The action of ACTH and (Bu) 2 cAMP to promote the secretion of 17α-hydroxylated C 21 -steroids and C 19 -steroids, on the other hand, appears to reflect an increase in the rate of cholesterol side-chain cleavage, as well as an increase in 17α-hydroxylase and possibly also 17,20-lyase activities.
ACGME 2011 Duty-Hour Guidelines: Consequences Expected by Radiology Residency Directors and Chief Residents

Purpose The aim of this study was to assess perceptions of the 2011 ACGME duty-hour guidelines among radiology residency directors and chief residents with regard to resident training, the practice of radiology, the quality of resident life, and faculty and staff costs. Methods An online survey was sent to radiology program directors and chief residents via the Association of University Radiologists. Results The response rates were 36.7% for program directors and 18.6% for chief residents. Responses were generally weakly negative from both radiology program directors and chief residents. Conclusions Both radiology program directors and chief residents have negative perceptions of the effect of the 2011 ACGME duty-hour guidelines on radiology residency programs. There was significant disagreement between program directors and chief residents with regard to whether attending radiologists or residents would be more affected by the new guidelines.
Transient phosphorylation by ATP of a 160 000 dalton protein in rod outer segments of Bufo marinus

Radioactive phosphate was incorporated from [γ-32P]ATP into a 160 000 dalton protein from preparations of highly purified toad retinal rod outer segment membranes. Maximal incorporation occurred at 1μM ATP, and turnover in the presence of nonradioactive substrate was rapid, showing that the 160 kdalton protein catalyzes ATP hydrolysis. The 160 kdalton intermediate was sensitive to hydroxylamine, suggesting an acyl linkage between the protein and phosphate. Ionic requirements for phosphorylation showed the ATPase is different from other membrane-bound ionic pumps. The phosphorylated intermediate was almost completely suppressed by 20 μM vanadate, and partial suppression occurred at lower concentrations. About one 160 kdalton protein was labelled per 30 000 molecules of rhodopsin. Although [γ-32P]GTP labeled the protein, the ATPase was far more specific for adenine than guanine nucleotides. The specificity for ATP and sensitivity to vanadate of the intermediate suggest a relation to an ATP-dependent structural change which occurs in stacks of outer segment discs (Thacher, S.M.; (1980) Fed. Proc. 39, 2066).
The Size of Government and U.S.-European Differences in Economic Performance

An influential strand of recent research has claimed that large governments in European countries explain their weaker long-term economic performance compared to the U.S. On the other hand, despite these alleged costs, large governments have been popular with electorates. This paper seeks to shed light on this apparent inconsistency; it confirms an adverse effect of taxes on labor supply, but also finds evidence of efficiency-increasing government intervention. However, and especially in the core "Rhineland-model" European countries, actual government policies often depart from such efficient interventions, pointing to the possibility that voters prefer redistribution even at the cost of allocational efficiency.
Ninety-deg. bends in low-index contrast waveguides

We discuss the use of multiple layer air trench and silicon strip structures to realize high efficiency 90° bends for low index contrast waveguides. We use a micro-genetic algorithm (mGA) coupled with a 2-D finite difference time domain method to perform rigorous electromagnetic optimization of multi-layer structures for single mode waveguides. We find that a 3-layer air trench structure can be designed for a 90° waveguide bend that exhibits 97.2% efficiency for TM polarized light at a wavelength of 1.55 μm. We are also able to design five- and six-layer silicon strip bends that have high efficiency for both TE and TM polarizations. For example, simulation results for a six-layer design show 95.2% and 97.2% for TE and TM polarizations, respectively. Moreover, the bend efficiency for each polarization state is greater than 90% over a broad wavelength range (1.5 μm to 1.7 μm).
Delayed response in cats after frontal lesions extending beyond the gyrus proreus.

Abstract The experiment tested the hypothesis that the consistently smaller impairment of delayed responding after prefrontal ablations in cats as compared to monkeys may be attributed to incomplete lesions of the projection area of the mediodorsal thalamic nucleus in the cat. The results disconfirmed the hypothesis: cats with ablations of both the gyrus proreus and the periproreal cortex (excluding the precruciate area) showed some savings in retention of delayed responses and were not more severely impaired than the cats with lesions restricted to the gyrus proreus. Cats are less dependent on an intact frontal cortex for performance of delayed responses than are adult monkeys. No evidence was found that the frontal cortical mechanism mediating delayed responses in the cat extends beyond the gyrus proreus.or can be described by the focus and field paradigm.
Adrenocorticotropin and cortisol responses to a naloxone challenge and risk of alcoholism.

Abstract Background: Because abnormalities in opioid neurotransmission appear to underlie some of the inherited risk for alcoholism, we examined the effects of naloxone, an opioid antagonist, on corticotropin and cortisol responses in nonalcoholic subjects differentiated by paternal history of alcoholism. Methods: Placebo-controlled, balanced, within-subject design involving 2 test days over a period of 3 to 7 days. Thirty-six subjects (67% male; 53% paternal-history-positive; mean age = 25.0 years) were screened to exclude substance abuse or dependence. Subjects received intravenous naloxone 125 μg/kg or placebo, with sessions in random order. Plasma corticotropin and cortisol were measured for up to 120 min post infusion. Results: Corticotropin responses at baseline and following naloxone did not differ by paternal history of alcoholism; however, paternal-history-positive subjects exhibited greater cortisol concentrations at baseline, and at 15 and 30 min after naloxone administration. Paternal-history-positive subjects also had an earlier and greater peak cortisol response to naloxone and a nonsignificant trend for a greater area under the cortisol time curve than paternal-history-negative subjects. Conclusions: These findings suggest that individuals with greater vulnerability to alcoholism may have altered Hypothalamic-pituitary axis (HPA) dynamics, a finding that is consistent with a growing body of data on the role of opioidergic neurotransmission in the inherited risk of alcoholism.
Squint: barely visible library support for CS1

Squint is a Java library developed to support the use of event-driven programming and network applications in programming examples for a CS1 curriculum. We present the design of the library, emphasizing techniques employed to minimize the effort students expend learning features specific to the library. We also compare Squint to an established library that supports event-driven programming in CS1, emphasizing ways in which the two libraries support similar pedagogical approaches.
Cucumber mosaic virus-associated RNA 5 VI. Characterization and denaturation-renaturation behavior of the double-stranded form

Abstract The double-stranded form of cucumber mosaic virus-associated RNA 5 has been purified and further characterized. Its molecular weight determined by sedimentation equilibrium is 2.15 · 105. The buoyant density calculated from its symmetrical distribution in Cs2SO4, following isopycnic ultracentrifugation, is 1.615 g/cm3. The sedimentation rate of double-stranded cucumber mosaic virus-associated RNA 5 is slightly greater than that of cucumber mosaic virus-associated RNA 5; its electrophoretic mobility in polyacrylamide gel (2.4%) is less than that of cucumber mosaic virus-associated RNA 5. By the above standards the double-stranded cucumber mosaic virus-associated RNA 5 preparations used were found to be homogeneous in size as well as density. Thermal denaturation monitored by means of ultraviolet light absorption produced multitransitional denaturation profiles. The average melting temperature (Tm) was 88°C in 0.1 × SSC. Monotransitional denaturation profiles and slightly higher Tm values were obtained when resistance against ribonuclease digestion was measured. These denaturation experiments and other properties led to the conclusion that double-stranded cucumber mosaic virus-associated RNA 5 and the double-stranded form of peanut stunt virus-associated RNA 5 are small double-stranded nucleic acids with several homostable base-pair regions, characterized by distinct G + C contents and Tm values.
Subarachnoid clonidine for labor pain: the two sides of the coin

Subarachnoid injections of clonidine for labor pain still remain controversial. Tebaldi et al. [1] have recently raised concerns that combination of subarachnoid bupivacaine, 2.5 mg, sufentanil, 2....
Diagnosis and treatment of hyponatremia

Originally published online July 2, 2014. Address correspondence to Nicolaos E. Madias, MD, St. Elizabeth’s Medical Center, 736 Cambridge St, Boston, MA 02135. E-mail: nicolaos.madias@steward.org 2014 by the National Kidney Foundation, Inc. 0272-6386/$36.00 http://dx.doi.org/10.1053/j.ajkd.2014.06.001 Hyponatremia, the most common electrolyte disorder encountered, is associated with increased morbidity and mortality even in its milder forms. Despite novel pathophysiologic insights, diagnostic approaches, and management options, hyponatremia remains a challenge for clinicians. In a recent article copublished in the European Journal of Endocrinology, Intensive Care Medicine, and Nephrology Dialysis and Transplantation, Spasovski et al reported a clinical practice guideline on the diagnosis and treatment of hyponatremia that aims to assist clinicians in everyday practice. Revisiting hyponatremia was considered necessary to incorporate evidencebased approaches to patient care and provide reliable evaluation of key clinical decisions. The guideline was developed jointly by the European Society of Intensive Care Medicine, the European Society of Endocrinology, and the European Renal Association– European Dialysis and Transplant Association, represented by the European Renal Best Practice. Established databases were searched for evidence and searches were updated on December 10, 2012.
Implications of aquatic animal health for human health.

Human health and aquatic animal health are organically related at three distinct interfaces. Aquatic animals serve as important contributors to the nutritional protein, lipid, and vitamin requireme...
Low temperature breakdown in silicon Zener diode

Abstract Observations of well developed negative resistance regions in both forward and reversed biased Si Zener diodes are explained in terms of a combination of impact ionization in the bulk material and Zener breakdown in the junction.
An Analysis of String Instrumentalists' Performed Intonational Adjustments Within an Ascending and Descending Pitch Set

The purpose of this study was to observe string instrumentalists' intonational performances within the duration of selected pitches. Additional aspects of the study included the effects of directionality of performed pitch sets, intonational tendencies associated with vibrato versus no vibrato, and differences in intonational performance among specific instrument groups. Forty-eight string players were randomly selected as subjects. Each subject performed pitch sets ascending and descending with vibrato and without vibrato. Performance tones were tape-recorded and analyzed for the highest and lowest points (pitch location 1 and pitch location 2) in order of occurrence within each tone according to cents sharp or flat relative to equal temperament. Results indicated that pitch location 2 was performed significantly sharper than pitch location 1; however, a significant interaction was found among pitch location, pitch set direction, and individual tones. Descending pitch sets were performed significantly sh...
Evaluation of the Patient With Fever of Undetermined Origin

Abstract The etiology and evaluation of fever of undetermined origin (FUO) has changed during the 35 years since it was first described by Petersdorf and Beeson. With the advent of advanced bacteriologic culture techniques and noninvasive radiographic studies, occult infection and neoplasm have been more readily detectable and thus have moved down the list of the most common etiologies of FUO. These categories have been replaced recently by collagen vascular disease as the most commonly diagnosed cause of FUO. The evaluation of a patient with FUO requires a thorough knowledge of the potential causes of the disorder, the ability to elicit subtle clues in the history and physical examination, and an appreciation of the use of various diagnostic tests.