cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of H-Bond Donor Lipids on Phosphatidylinositol-3,4,5-Trisphosphate Ionization and Clustering

Abstract The phosphoinositide, phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P 3 ), is a key signaling lipid in the inner leaflet of the cell plasma membrane, regulating diverse signaling pathways including cell growth and migration. In this study we investigate the impact of the hydrogen-bond donor lipids phosphatidylethanolamine (PE) and phosphatidylinositol (PI) on the charge and phase behavior of PI(3,4,5)P 3 . PE and PI can interact with PI(3,4,5)P 3 through hydrogen-bond formation, leading to altered ionization behavior and charge distribution within the PI(3,4,5)P 3 headgroup. We quantify the altered PI(3,4,5)P 3 ionization behavior using a multistate ionization model to obtain micro-pK a values for the ionization of each phosphate group. The presence of PE leads to a decrease in the pK a values for the initial deprotonation of PI(3,4,5)P 3 , which describes the removal of the first proton of the three protons remaining at the phosphomonoester groups at pH 4.0. The decrease in these micro-pK a values thus leads to a higher charge at low pH. Additionally, the charge distribution changes lead to increased charge on the 3- and 5-phosphates. In the presence of PI, the final deprotonation of PI(3,4,5)P 3 is delayed, leading to a lower charge at high pH. This is due to a combination of hydrogen-bond formation between PI and PI(3,4,5)P 3 , and increased surface charge due to the addition of the negatively charged PI. The interaction between PI and PI(3,4,5)P 3 leads to the formation of PI and PI(3,4,5)P 3 -enriched domains within the membrane. These domains may have a critical impact on PI(3,4,5)P 3 -signaling. We also reevaluate results for all phosphatidylinositol bisphosphates as well as for PI(4,5)P 2 in complex lipid mixtures with the multistate ionization model.
Reducing sedentary behaviour to decrease chronic low back pain: the stand back randomised trial.

Objective The Stand Back study evaluated the feasibility and effects of a multicomponent intervention targeting reduced prolonged sitting and pain self-management in desk workers with chronic low back pain (LBP). Methods This randomised controlled trial recruited 27 individuals with chronic LBP, Oswestry Disability Index (ODI) >10% and desk jobs (sitting ≥20 hours/week). Participants were randomised within strata of ODI (>10%– Results Baseline mean (SD) age was 52 (11) years, 78% were women, and ODI was 24.1 (10.5)%. Across the 6-month follow-up in models adjusted for baseline value, work sitting time was 1.5 hour/day (P Conclusion An intervention coupling behavioural counselling targeting reduced sedentary behaviour and pain self-management is a translatable treatment strategy that shows promise for treating chronic LBP in desk-bound employees. Trial registration number NCT0224687; Pre-results.
An 8-week-old infant with trisomy 13: dilemmas for medical decision making.

Patau syndrome, trisomy 13, is a rare genetic condition with notable physical and mental characteristics and an average reported lifespan of 9 months. For years, trisomy 13 was regarded as a lethal condition; however, a few infants survive for many years, creating a dilemma for both the medical practitioner and the family in terms of the appropriateness and timeliness of specific medical interventions. Even in the face of severe mental and physical limitations, most families of children with trisomy 13 report their experiences as enriching. Appropriate and timely surgical interventions and medical treatments have been shown to increase survival for some infants. Early palliative care helps to limit physical and emotional suffering, and allow the family to create a legacy that their baby’s life had meaning, regardless of how long they survive. We present a case of an 8-week-old infant with trisomy 13 to illustrate some of the medical decision making dilemmas faced by both medical practitioner and the family.
Youth Experiences Survey (YES): Exploring the Scope and Complexity of Sex Trafficking in a Sample of Youth Experiencing Homelessness

In the United States, sex trafficking victims have been identified at ages across the lifespan but young persons (under age 25) have been found to have unique vulnerabilities. At-risk youth, such a...
Chocolate and Pain Tolerance

Chocolate has a reputation as a pain reliever that spans hundreds of years. Mechanisms of chocolate analgesia could include associative learning and direct chemical activity. Associative learning is likely mediated through endogenous opioid activity. Opioid activity in response to eating is likely an evolutionary response to promote feeding in the face of danger. Although several different chemical components of chocolate could directly reduce pain, the most likely compounds are flavonoids. Flavonoids both decrease inflammation and diminish trigeminal nerve activity. Increased pain tolerance from chocolate likely reflects some combination of both learning and direct chemical activity.
Planning of Fast-Charging Stations for a Battery Electric Bus System under Energy Consumption Uncertainty

Battery-powered electric buses are gaining popularity as an energy-efficient and emission-free alternative for bus fleets. However, battery electric buses continue to struggle with concerns related...
Middle Range Theory

References to middle range theories, middle range theorizing, and middle range concepts are increasingly common in organizational research. The growing frequency of their use may indicate the onset of a new trend, perhaps even a new strategy of inquiry for organizational research. The middle range conceptualization, however, like most research tools, has limitations as well as advantages. These potentially offsetting factors require critical evaluation before the middle range notion can be further endorsed. The purpose of this paper is to provide such an overview of the middle range approach, rendering particular attention to the nature and meaning of middle range notions for understanding organizations and organizational behavior. In addition, we will offer some pragmatic suggestions for conducting research consonant with the middle range orientation.
Designing an SOA for P2P On-Demand Video Delivery

Compared with the traditional client/server streaming model, peer-assisted video streaming has been shown to provide better scalability with lower infrastructure cost. In this chapter, we describe how peer-assisted video streaming can be implemented through real-time service oriented architecture. This chapter presents an overall design of the Peer-Assisted ContenT Service (PACTS). We discuss the motivation, principles and service oriented architecture of PACTS modules and specify the workflow among them. By organizing elements of traditional video streaming and peer to peer computing into loosely-coupled composable middleware services and distributing them among participating entities, PACTS enables high-quality low-cost video streaming at a large scale and in real time. We illustrate the challenges and our approaches in designing distributed and highly efficient algorithms. In particular, the algorithms for performing peering-selection and incentive-driven pre-fetching are studied in detail. These designs are extensively evaluated by packet-level simulations which are beyond the scope of this paper. We show that our implementation of PACTS effectively offload server’s bandwidth demand without sacrificing the service quality. This benefit is further verified in dynamic settings with system churns.
Heme-copper relationship of cytochrome oxidase in rat brain insitu

The role of copper aa3 in relation to heme aa3 of cytochrome oxidase in electron transfer and oxygen utilization is poorly understood in vitro. In an attempt to study this in situ, we have simultaneously monitored the steady state redox changes of heme aa3 and copper aa3 in an isolated perfused rat head model (skull intact, muscle removed). By means of reflectance spectrophotometry the redox reactions of heme aa3 and copper aa3 were continuously monitored using 605-625 nm and 815-920 nm wavelength pairs, respectively. The reaction kinetics of these components in response to transient perfusion interruption in energized and de-energized preparations were then examined. We found that in response to perfusion interruption, soon after full reduction, the copper signal begins to change toward oxidation despite continuation of anoxic insult and progressive reduction of heme aa3. This phenomenon disappeared by pretreatment of the preparation with 2,4-dinitrophenol. A schematic sequence of electron transport in situ is proposed which emphasizes an active role for Cua in this sequence.
Preparation and Properties of Antibodies to Gangliosides

In the limited space available I would like to consider some of the major problems encountered in immunological studies of gangliosides and neutral glycosphingolipids (GSLs), and some new approaches to these problems. Several comprehensive reviews of glycolipid immunology have been published recently1–5. The problems arise from the weak immunogenicity of many GSLs and from the amphipathic nature of these compounds.
Perceptual basemaps reloaded: The role basemaps play in eliciting perceptions

This article describes the influence of various basemaps in Perceptual Dialectology, on the national and state levels. The 180 perceptual maps of the United States and Tennessee were divided into six types of basemaps; tabulated results show that basemaps play a different role on the national and state level. On the national level, basemaps that have features reminiscent of boundaries (state lines or interstates) bias the respondents’ answers. On the state level, on the other hand, the map features do not seem to influence the results in any discernible way: at times the informants seemingly go against the details present on the basemap. This striking difference indicates that, though the respondents rely on basemap details at the national level, where they may not have enough experience with the whole country, they don’t pay much attention to the state-level basemap details as they follow their own more detailed ideas about perceptions.
Talk on the Playground: The Neighborhood Context of School Choice

Despite consensus that neighborhoods influence children's outcomes, we know less about the mechanisms that cause neighborhood inequality and produce those outcomes. Existing research overlooks how ...
Grab ‘em by the masculinity: changes in gendered beliefs and sexism following the 2016 US presidential election

ABSTRACTDue in part to Hillary Clinton’s historic candidacy, gender was a salient dimension of the 2016 US presidential election. In particular, the purported masculinity and femininity of each can...
Mary Tudor, the First Sovereign Queen of England: The Politics of Blood, Gender, Law, and Religion in the 1500s

This chapter explores the events surrounding the contested succession to the English throne in 1553. That summer, 15-year-old King Edward VI lay dying of a pulmonary infection. Edward, a Protestant, had worked to reform the English church according to Calvinist principles. As his condition worsened, he worried that his Protestant reforms would be overturned if he allowed his Catholic sister Mary to inherit the throne. Although Edward’s father Henry VIII had placed Mary second in line to Edward, the king and his advisers came up with a plan to declare her ineligible, and instead give the crown to his Protestant cousin Jane Grey. The Duke of Northumberland, Edward’s main adviser and Jane’s father-in-law, led the efforts after Edward’s death, and most assumed he would succeed. Few expected much from Mary, as she had constantly been on the defensive during Edward’s reign, and because as a single woman she was not expected to be able to lead efficiently. However, Mary surprised even experienced politicians and foreign observers by taking a swift and decisive stance. In the end, she succeeded, becoming the first woman to ever rule England. Her story yields a number of leadership insights.
Using ethanol for continuous biodiesel production with trace catalyst and CO2 co-solvent

Abstract The continuous biodiesel production process under sub- and supercritical conditions using a trace amount of potassium hydroxide (KOH) as a catalyst has been studied. CO2 was added as a co-solvent to reduce the reaction time and increase biodiesel yield. The proposed procedure enables simultaneous transesterification and esterification of triglycerides and free fatty acid (FFA), respectively. The shorter reaction time and milder reaction conditions may reduce energy consumption due to the simplification of the separation and purification steps. The process variables, including reaction temperature, ethanol to oil molar ratio, catalyst amount, and process pressure, were systematically optimized. The highest biodiesel yield (98.12%) was obtained after a 25-min reaction time using only 0.11% wt. of KOH and a 20:1 ethanol to oil ratio. The process optimum temperature and pressure were 240 °C and 120 bar, respectively. The proposed kinetic model suggested a first-order reaction with an activation energy of 15.7 kJ·mol−1 and a reaction rate constant of 0.0398/min−1. The thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy were calculated as 144.82 kJ·mol−1, 11.4 kJ·mol−1, −0.26 kJ·mol−1 and at 240 °C, respectively.
Affordable Care Act Entrenchment

The Affordable Care Act (ACA) is the most challenged — and the most resilient — statute in modern American history. Through and despite hundreds of court challenges, scores of congressional repeal efforts, unexpected state resistance, gutting by the Supreme Court, unprecedented administrative strangulation, and criticism from the beginning that the statute did not go far enough to embrace the principle of universal healthcare, the ACA has changed the way many Americans and the political arena think about healthcare and the entitlement to it. Over its ten-year lifespan, the ACA went from being the rallying cry of the GOP in 2010, to the center of the Democratic platform in 2018, catapulting universal healthcare to the top of the 2020 Democratic presidential primary agenda. It began as a statute criticized for its practical compromises and its incrementalism — including leaving most insurance in the private market and retaining state control over large swaths of health policy — but those very compromises have, surprisingly, proved key to the ACA’s resilience. They have also been instrumental in the ACA’s entrenchment of not only its own reforms but also a broader, emerging principle of a universal right to healthcare. The idea of health-care for all Americans administered through the federal government was long viewed as political suicide, including as recently as the 2016 presidential election. In an astonishingly fast turnaround, that idea has now been considered and debated by every Democratic presidential hopeful. The ACA’s principles have been codified outside of federal law and into state law, voted on in ballot initiatives, and advocated for on late-night TV. The Supreme Court has treated the ACA differently from other laws. Core features of the ACA — a law that Republicans have sought to repeal scores of times — are now mainstream positions in the Republican Party. This Article offers a comprehensive account of the ACA’s structure, the challenges it survived, and how a law that itself evinces a philosophical ambivalence about the right to government-provided healthcare has nevertheless made that right politically and practically possible for the first time in American history. We examine not only court cases and the political tides but also the statute’s governance, implementation, and financing structures to tell a story of entrenchment through multiple modalities — architectural, legal, democratic, political, financial, and expressive — and normative transformation. Legislation scholars will see in this story themes that echo theoretical concepts of special statutes — statutes whose norms transform the legal landscape beyond the statute itself and change the way we think about fundamental rights. Despite our doubts about the practical payoff of those theories, the concept is a helpful jumping-off point for a more detailed exploration of how the particulars of statutory design can facilitate entrenchment and of the various forms entrenchment can take.
Multichannel spike deconvolution in calcium imaging (Conference Presentation)

The problem of accurately inferring the firing time of neurons from fluorescent microscopy measurements such as calcium imaging is crucial for deciphering the dynamics of neural spiking activity during different tasks. The fluorescence signals from calcium images can be modeled as the convolution of the neural spikes (action potential) with an exponentially decaying kernel whose decay is governed by the type of calcium indicator used. Calcium signals exhibit excellent spatial resolution and it is possible to record individual neural activity from a large population of neurons. However, the main drawback of calcium imaging is that it has a poor temporal resolution due to the slow dynamics of calcium indicators and scanning limitations of existing microscopes. Existing spike deconvolution algorithms obtain a representation of spiking activity at a rate that is identical to the acquisition rate of calcium signals (typically <60Hz). However, this does not accurately capture the true spiking activity as typical neural spike separation could be <<5ms. In this paper, we show that simultaneously using the measurements from multiple neurons can be combined with accurate modeling of spiking activity to overcome these limitations. The main idea is to utilize the inherent multichannel structure of the problem. Calcium traces from different neurons will be considered as the output of the same unknown filter excited by different inputs corresponding to the spiking activity of different neurons. We will develop a sparse reconstruction algorithm that can solve this multichannel blind deconvolution problem from subsampled measurements and simultaneously recover the sparse neural activity at a rate that is representative of the true neural activity.
Testimony of Gail Heriot Professor of Law, University of San Diego A Member, U.S. Commission on Civil Rights Before the Commission on Law Enforcement and the Administration of Justice July 21, 2020

On July 21, 2020, in the wake of a month of riots as well as peaceful protests following the death of George Floyd, Gail Heriot testified before the President’s Commission on Law Enforcement and the Administration of Justice on the topic of respect for law enforcement and the rule of law.
Solution structures of the Shewanella woodyi H-NOX protein in the presence and absence of soluble guanylyl cyclase stimulator IWP-051

Abstract Heme-nitric oxide/oxygen binding (H-NOX) domains bind gaseous ligands for signal transduction in organisms spanning prokaryotic and eukaryotic kingdoms. In the bioluminescent marine bacterium Shewanella woodyi (Sw), H-NOX proteins regulate quorum sensing and biofilm formation. In higher animals, soluble guanylyl cyclase (sGC) binds nitric oxide with an H-NOX domain to induce cyclase activity and regulate vascular tone, wound healing and memory formation. sGC also binds stimulator compounds targeting cardiovascular disease. The molecular details of stimulator binding to sGC remain obscure but involve a binding pocket near an interface between H-NOX and coiled-coil domains. Here, we report the full NMR structure for CO-ligated Sw H-NOX in the presence and absence of stimulator compound IWP-051, and its backbone dynamics. Non-planar heme geometry was retained using a semi-empirical quantum potential energy approach. Although IWP-051 binding is weak, a single binding conformation was found at the interface of the two H-NOX subdomains. Binding lead to rotation of the subdomains and closure of the binding pocket. Backbone dynamics for the protein are similar across both domains except for two helix-connecting loops, which display increased dynamics that are further enhanced by compound binding. Structure-based sequence analyses indicate high sequence diversity in the binding pocket, but the pocket itself appears conserved among H-NOX proteins. The largest dynamical loop lies at the interface between Sw H-NOX and its binding partner as well as in the interface with the coiled coil in sGC, suggesting a critical role for the loop in signal transduction.
From Futile to Utile: Addressing the Key Role of Florida’s Electric Utility Companies in Mitigating Sea Level Rise

Florida’s unique tax structure, revenue sources, and diverse environment provide an opportunity to address sea-level rise through the lens of the highest carbon emitters: electric utility companies. The proposed solutions include: [1] a gradual increase in taxes and fees on some aspects of Florida electric utility companies, [2] offering tax credits and subsidies for transitioning to more environmentally-friendly power-generation, and [3] reforming electric utility regulations as an incentive to adopt a more climate-conscious, public welfare approach — all while maintaining a profit-making structure that can both maintain revenue and reduce the impact of sea level rise in Florida. An analysis of three potential solutions indicates that the case for carbon dioxide mitigation initiatives is strong and able to yield significant revenue over time, while simultaneously contributing to the overall reduction in emissions to help reduce the impact of sea level rise in Florida and beyond.
Engineering Resilient Systems: Achieving Stakeholder Value Through Design Principles and System Operations

Engineering managers work with system designers, system operators, and stakeholders who value the system's performance and seek to deliver stakeholder value. Engineering resilient systems is an emerging research field since all systems face future uncertainties including new missions, new requirements, unplanned environments, and unplanned events that cause disruptions during operation. The ability of a system to provide stakeholder value depends on the system design and the ability of the system operator to react to the disruption(s). A resilient design offers options to respond to new missions, environments, and disruptions through system automation or operator actions. The engineering resilience literature uses overlapping definitions. It does not adequately distinguish between resilient design principles and the means they provide for operators to respond to mission disruptions and the ability to modify the system for new missions. This article uses the engineered systems resilience literature to provide a clearer lexicon. It then proposes a framework, the principles-means-ends diagram, for engineering managers to communicate with stakeholders, operators, and designers about the benefits of engineered systems’ resilience, the opportunities for designers to use resilience design principles to create more resilient designs, and the roles of the operators in achieving resilience during operations. We propose a principles-means-ends diagram for resilient engineered systems, which provides a holistic view for designers, operators, and stakeholders to visualize how their actions connect to others and encourages communication between them to create a more resilient engineered system.
Radiation safety considerations for diagnostic radiology personnel

In radiation protection, the guiding philosophy is ALARA (as low as reasonably achievable), and states have regulatory authority. Dose limits are in part based on effective dose equivalent and differences in tissue sensitivities. In diagnostic radiology, the main source of occupational dose is scattered radiation from the patient--particularly from fluoroscopically guided procedures. Personnel stand near patients for long times, and angulated geometries with C-arm equipment may result in high personnel doses from backscatter. For all procedures, judicious applications of time, distance, and shielding affect dose. Appropriate use includes collimating properly, optimizing beam-on time, minimizing distances between image intensifier and patient, ensuring sufficient distance between patient and x-ray tube, and optimizing exposure rates for image quality and dose. Although dose limits typically regulate maximum whole-body dose, protective clothing worn by fluoroscopists reduces personnel risks; weighting factors can be applied to estimate effective dose equivalent. Pregnant personnel have lower limits, which apply only with voluntary declaration of pregnancy. With appropriate precautions, fetal doses can typically remain within recommended limits without changes in occupational tasks. Radiation workers in each state must ensure that regulations are appropriate. Then, for protection of both employee and employers, the rules can and must be followed.
Improved methods for understanding the role of predation on dreissenid population dynamics

Impacts of dreissenid mussels (Dreissena spp.) on Great Lakes ecosystems are well documented, and a better understanding of mechanisms that cause variation in dreissenid abundance is needed. An outstanding question is how much dreissenid biomass is consumed by fish predation. A significant difficulty for investigating dreissenid consumption by fish is that dreissenids in stomachs are often a mix of indigestible shell and flesh, which can bias bioenergetics models and estimates of daily ration. Here, we develop an analysis to convert crushed shell and flesh mixtures found in fish diets to dry weight of digestible dreissenid flesh. Quagga Dreissena rostiformis bugensis and zebra Dreissena polymorpha mussels were used in separate dry weight analyses simulating stomach contents ranging from individual mussels to aggregates of each species. A species-specific dry weight relationship was observed when comparing flesh-only dry weight to total dry weight (shell + flesh) for individual dreissenid but not for aggregates. Thus, the model is applicable in providing more precise estimates of dreissenid flesh dry weight in fish diets.
Political Kinship in Pakistan: Descent, Marriage and Government Stability

Stephen M. Lyon’s Political Kinship in Pakistan examines the contestations of political power at both local and central levels through the prism of kinship that permeates the foundations of Pakista...
Image Reconstruction from Accelerated Slice-Interleaved Diffusion Encoding Data

We present a reconstruction scheme for diffusion MRI data acquired using slice-interleaved diffusion encoding (SIDE). We show that, when combined with multi-band imaging, the method is capable of reducing the amount of data that needs to be acquired by as much as 25 times, therefore remarkably speeding up acquisition and making high angular resolution diffusion imaging much more feasible, particularly for pediatric, elderly, and claustrophobic patients. In contrast to the conventional approach of acquiring a full diffusion-weighted (DW) volume for each diffusion wavevector, SIDE acquires for each repetition time (TR) a volume consisting of interleaved slice groups, each corresponding to a different diffusion wavevector. This allows SIDE to rapidly acquire information associated with a larger number of wavevectors within a short period of time. We formulate the inverse problem involved in recovering the full DW images as a constrained variational problem regularized by multidimensional total variation. The problem can be solved efficiently using the alternating direction method of multipliers (ADMM). Experiment results based on SIDE data of adults indicate that DW images can be recovered with high fidelity despite high undersampling for multifold acceleration.
Reflections on altruism, action, and “moral imagination” in the context of the White Savior

Caring, we suppose, is nice. Pledging to do better is quaint. Performing acts of care is kind. But changing the ways in which the world functions is a (in)surmountable task that must be undertaken....
The CORE (Consensus on Relevant Elements) Approach to Determining Initial Core Components of an Innovation

Identifying an intervention’s core components is indispensable to gauging whether an intervention is implemented with fidelity and/or is modified; it is often a multi-stage process, starting with the first stage of identifying an initial set of core components that are gradually refined. This first stage of identifying initial core components has not been thoroughly examined. Without a clear set of steps to follow, interventions may vary in the rigor and thought applied to identifying their initial core components. We devised the CORE (Consensus on Relevant Elements) approach to synthesize opinions of intervention developers/implementers to identify an intervention’s initial core components, particularly applicable to innovative interventions. We applied CORE to a peer-based intervention that aids military veterans with post-incarceration community reintegration. Our CORE application involved four intervention developers/implementers and two moderators to facilitate the seven CORE steps. Our CORE application had two iterations, moving through Steps 1 (individual core component suggestions) through 7 (group discussion for consensus), then repeating Steps 4 (consolidation of component definitions) through 7. This resulted in 18 consensus-reached initial core components of the peer-based intervention, down from the 60 that the developers/implementers individually suggested at Step 1. Removed components were deemed to not threaten the intervention’s effectiveness even if absent. CORE contributes to filling a critical gap regarding identifying an intervention’s initial core components (so that the identified components can be subsequently refined), by providing concrete steps for synthesizing the knowledge of an intervention’s developers/implementers. Future research should examine CORE’s utility across various interventions and implementation settings.
THE PRODUCTIVITY PROBLEM IN U.S. SHIPBUILDING

SHIPBUILDING PRODUCTIVITY IN THE U.S. AND ABROAD SHIPBUILDING PRACTICES OVERSEAS AND PROBLEMS IN THEIR APPLICATION IN THE U.S
Chapter 5 - Multi-photon quantum interferometry

This chapter discusses the multi-photon quantum interferometry. The chapter exhibits different trends in the development of entangled-photon interferometry using spontaneous parametric down-conversion (SPDC). SPDC of one photon into a pair is of one two types, type I or type II, depending on whether the two photons of the down-conversion pair have the same polarization or orthogonal polarizations. The two photons of a pair can leave the down-converting medium either in the same direction or in different directions, the collinear and noncollinear case respectively. In the case of type-II SPDC, the two photons of each down-conversion pair have orthogonal rather than identical polarizations. This allows the entanglement of their states to involve polarization in addition to those other quantities potentially involved in the type-I case. The entanglement of three or more photons helps to test locality, reality and completeness assumptions of EPR using entangled three-particle states.
An improved adaptive multi-start approach to finding near-optimal solutions to the Euclidean TSP

We present an "adaptive multi-start" genetic algorithm for the Euclidean traveling salesman problem that uses a population of tours locally optimized by the Lin-Kernighan algorithm. An all-parent cross-breeding technique, chosen to exploit the structure of the search space, generates better locally optimized tours. Our work generalizes and improves upon the approach of Boese et al. [2]. Experiments show the algorithm is a vast improvement over simple "multi-start," i.e., repeatedly applying Lin-Kernighan to many random initial tours. Both for random and several standard TSPLIB [5] instances, it is able to find nearly optimal (or optimal) tours for problems of several thousand cities in a few minutes on a Pentium Pro workstation. We find these results are competitive both in time and tour length with one of the most successful TSP algorithms, Iterated Lin-Kernighan.
Bridging the gap between AI and IR

Information retrieval, in the broadest sense of the term, includes a concern with 'expert' or 'knowledge-based' systems and their potential future successors. It is unlikely that sophisticated systems of this sort can be developed in such a way as to use an entire natural language without the assistance of an advanced, unified theory of language and logic. The need for and probable character of such a theory are discussed.
Optimization Using Tuple Subsumption

A tuple t1 of relation R subsumes tuple t2 of R, with respect to a query Q if for every database, tuple t1 derives all, and possibly more, answers to query Q than derived by tuple t2. Therefore, the subsumed tuple t2 can be ignored with respect to Q in the presence of tuple t1 in relation R. This property finds use in a large number of problems. For instance: during query optimization subsumed tuples can be ignored thereby avoiding the computation of redundant answers; the size of cached information in distributed and object oriented systems can be reduced by omitting subsumed tuples; constraints need not be checked and rules need not be recomputed when provably subsumed updates are made. We give algorithms for deciding efficiently when a tuple subsumes another tuple for queries that use arbitrary mathematical functions. We characterize queries for which, whenever a set of tuples T subsumes a tuple t then one of the tuples in T also subsumed t, yielding efficiently verifiable cases of subsumption.
Gibbs sampling optimization in underwater sound problems

Parameter estimation in the ocean can be achieved in an optimal fashion by implementing approaches maximizing posterior probability distribution functions. Such approaches are, however, computationally intensive, often requiring the computation of complex probability distributions and searches for global maxima in spaces of a high dimension. In this work, it is shown how Gibbs Sampling, a Markov Chain Monte Carlo method, can be employed for the fast computation of posterior probability distributions, resulting in accurate and fast estimation of parameters related to problems in underwater acoustics. Source localization results obtained through maximum a posteriori estimation and optimization with Gibbs sampling are presented and compared to results obtained with conventional methods.
Theoretical detection threshold of the proton-acoustic range verification technique.

Purpose: Range verification in proton therapy using the proton-acoustic signal induced in the Bragg peak was investigated for typical clinical scenarios. The signal generation and detection processes were simulated in order to determine the signal-to-noise limits. Methods: An analytical model was used to calculate the dose distribution and local pressure rise (per proton) for beams of different energy (100 and 160 MeV) and spot widths (1, 5, and 10 mm) in a water phantom. In this method, the acoustic waves propagating from the Bragg peak were generated by the general 3D pressure wave equation implemented using a finite element method. Various beam pulse widths (0.1–10 μs) were simulated by convolving the acoustic waves with Gaussian kernels. A realistic PZT ultrasound transducer (5 cm diameter) was simulated with a Butterworth bandpass filter with consideration of random noise based on a model of thermal noise in the transducer. The signal-to-noise ratio on a per-proton basis was calculated, determining the minimum number of protons required to generate a detectable pulse. The maximum spatial resolution of the proton-acoustic imaging modality was also estimated from the signal spectrum. Results: The calculated noise in the transducer was 12–28 mPa, depending on the transducer central frequency (70–380more » kHz). The minimum number of protons detectable by the technique was on the order of 3–30 × 10{sup 6} per pulse, with 30–800 mGy dose per pulse at the Bragg peak. Wider pulses produced signal with lower acoustic frequencies, with 10 μs pulses producing signals with frequency less than 100 kHz. Conclusions: The proton-acoustic process was simulated using a realistic model and the minimal detection limit was established for proton-acoustic range validation. These limits correspond to a best case scenario with a single large detector with no losses and detector thermal noise as the sensitivity limiting factor. Our study indicated practical proton-acoustic range verification may be feasible with approximately 5 × 10{sup 6} protons/pulse and beam current.« less
Sulfation of fulvestrant by human liver cytosols and recombinant SULT1A1 and SULT1E1

Fulvestrant (Faslodex™) is a pure antiestrogen that is approved to treat hormone receptor-positive metastatic breast cancer in postmenopausal women. Previous studies have demonstrated that fulvestrant metabolism in humans involves cytochromes P450 and UDP-glucuronosyltransferases (UGTs). To date, fulvestrant sulfation has not been characterized. This study examined fulvestrant sulfation with nine recombinant sulfotransferases and found that only SULT1A1 and SULT1E1 displayed catalytic activity toward this substrate, with Km of 4.2 ± 0.99 and 0.2 ± 0.16 μM, respectively. In vitro assays of 104 human liver cytosols revealed marked individual variability that was highly correlated with β-naphthol sulfation (SULT1A1 diagnostic substrate; r = 0.98, P < 0.0001), but not with 17β-estradiol sulfation (SULT1E1 diagnostic substrate; r = 0.16, P = 0.10). Fulvestrant sulfation was correlated with both SULT1A1*1/2 genotype (P value = 0.023) and copy number (P < 0.0001). These studies suggest that factors influencing SULT1A1/1E1 tissue expression and/or enzymatic activity could influence the efficacy of fulvestrant therapy.
Inductance calculations for tapered helical MCGs

There is recent interest in developing small helical magnetocumulative generators (MCGs) capable of generating high voltage pulses with short pulse lengths. However, as the diameter of these generators decreases their energy and current gains decrease due to increased resistive losses and difficulties in properly aligning the armature relative to the center line of the generator. One possible way to achieve these objectives and overcome the limitations of these small generators is to taper their stator. This, however, increases the difficulty in calculating the initial inductance of the generator. In this paper, a simple mathematical model is presented for calculating the inductance of tapered generators. The calculations are in good agreement with the experimental results
[3H]Spiperone binds selectively to rat striatal D2 dopamine receptors in vivo: a kinetic and pharmacological analysis

We have determined the kinetic, equilibrium saturation, and pharmacological characteristics of [3H]spiperone ([3H]SPIP) binding to rat brain regional particulate fractions following i.v. injections of [3H]SPIP and compared these parameters to those determined in vitro with traditional ligand-homogenate binding assays. [3H]SPIP binding to rat striatum in vivo and in vitro occurs to a single class of non-interacting binding sites which possess the pharmacological properties of a D2 dopamine (DA) receptor. The potencies of neuroleptic drugs in inhibiting DA receptor-mediated behaviors correlate with their potencies at displacing striatal [3H]SPIP binding in vivo. While striatum possesses a similar density of [3H]SPIP binding sites in vivo (34 pmol/g) and in vitro (31 pmol/g), binding affinity in vivo is about 200 times lower than in vitro. This difference in binding affinities appears to arise from alterations of [3H]SPIP association and dissociation rate constants brought about by tissue homogenization. The implications of our findings for external imaging of DA receptors and studies of DA receptor function in human brain homogenates are discussed.
Effect of Carbon Dioxide on Cerebral Metabolism during Hypoxia-Ischemia in the Immature Rat

Effect of Carbon Dioxide on Cerebral Metabolism during Hypoxia-Ischemia in the Immature Rat
Anesthesia for Pacemaker Insertion

In recent years, the nature of pacemaker implantation in the United States has changed dramatically, as ad vances continue in the technology of pacemakers and the techniques for insertion. Changes ...
The static potential in quantum chromodynamics

Abstract The effective interaction between a static quark-antiquark pair is computed within the framework of 〈 G μv a G a μv 〉 ≠ 0. Due to the static approximation the interaction takes the form of a potential, which is in striking agreement with phenomenological potentials.
Fluorinated allenes: the syntheses of 1-fluoropropadiene, 1,1-difluoropropadiene and 1,1-difluoro-3-methyl-1,2-butadiene

Abstract Improved syntheses of 1-fluoropropadiene and 1,1-difluoropropadiene are presented as is the synthesis of a third reactive allene, 1,1-difluoro-3- methyl-1,2-butadiene. Gram quantities of these highly reactive fluorinated allenes may be prepared conveniently in high yield and purity. All three are reactive dienophiles and cycloadd regiospecifically using their non- fluorine-substituted double bonds.
Impact of weather variation on ground-source heat pump design

This article presents an investigation on the impact of year-to-year weather variability on the optimal design of a system for heating and cooling a building using a ground-source heat pump. The designs of a boiler–ground-source heat pump hybrid and a cooling tower–ground-source heat pump hybrid were optimized using a typical meteorological year (TMY2) weather file and also using 15 years of actual weather data. The results indicate that a design based on a TMY2 weather file may be undersized for a severe weather year; this is particularly true if the severe weather year is encountered during the first year of system operation. A cooling tower–ground-source heat pump hybrid model was developed, which includes the use of a backup boiler placed on the building side (rather than the loop side) of the system. It was found that the use of a boiler backup mitigated much of the negative impact of a severe weather year. The boiler supplied the heating during periods of particularly severe weather so that the grou...
Experiments on the conductivity of suspensions of ionically‐conductive spheres

This is a report on the ionic conductivity of monodisperse, neutrally-buoyant suspensions of ion-exchange beads, both AC total-ion conductivity and DC specific-ion conductivity of an electrochemically-active species. They represent the zero Peclet-number and the large Peclet-number limits of mass transfer, respectively. A rotating disc electrode was employed for the DC studies and a well mixed conductivity cell for the AC—for particle volume fractions ϕ ranging from zero to about 45%. Novel techniques were developed for rapidly determining the particle AC conductivity and for modifying the relative conductivity α of ion-exchange beads by poisoning with immobilely-bound ions. For α values, 0.044⩽ α ⩽ 1.48, of this study Maxwell's classical relation is shown to be adequate for ϕ ⩽ 0.5, which is, in agreement with Turner (1973, 1976). Our results for the DC conductivity differ somewhat from those of Andersen (1987) land show the weak dependence on particle Peclet number predicted by the dilute-suspension theory of Nir and Acrivos (1976) for Pe ≫ 1.
Gene-sex interactions in schizophrenia: focus on dopamine neurotransmission.

Schizophrenia is a severe mental disorder, with a highly complex and heterogenous clinical presentation. Our current perspectives posit that the pathogenic mechanisms of this illness lie in complex arrays of gene x environment interactions. Furthermore, several findings indicate that males have a higher susceptibility for schizophrenia, with earlier age of onset and overall poorer clinical prognosis. Based on these premises, several authors have recently begun exploring the possibility that the greater schizophrenia vulnerability in males may reflect specific gene x sex (GxS) interactions. Our knowledge on such GxS interactions in schizophrenia is still rudimentary; nevertheless, the bulk of preclinical evidence suggests that the molecular mechanisms for such interactions are likely contributed by the neurobiological effects of sex steroids on dopamine (DA) neurotransmission. Accordingly, several recent studies suggest a gender-specific association of certain DAergic genes with schizophrenia. These GxS interactions have been particularly documented for catechol-O-methyltransferase (COMT) and monoamine oxidase (MAO), the main enzymes catalyzing DA metabolism. In the present review, we will outline the current evidence on the interactions of DA-related genes and sex-related factors, and discuss the potential molecular substrates that may mediate their cooperative actions in schizophrenia pathogenesis.
Vitamin D metabolism and function

Vitamin D. By H.F. DeLuca. Pp.80. (Springer: Berlin, New York and Heidelberg, 1979.) DM29; $15.
Making a Case for Efficient Supercomputing: It is time for the computing community to use alternative metrics for evaluating performance.

A supercomputer evokes images of “big iron“ and speed; it is the Formula 1 racecar of computing. As we venture forth into the new millennium, however, I argue that efficiency, reliability, and availability will become the dominant issues by the end of this decade, not only for supercomputing, but also for computing in general.
Alcohol Consumption and Withdrawal in New-Onset Seizures

We studied alcohol use before the onset of a first seizure in 308 patients with seizures and 294 controls. The risk of seizures increased with increasing current alcohol use. For unprovoked seizures (i.e., seizures occurring without an antecedent event, such as a recent stroke), the adjusted odds ratios rose from 3-fold at intakes of 51 to 100 g of ethanol per day (95 percent confidence limits, 1.3 and 6.3), to 8-fold at 101 to 200 g per day (95 percent confidence limits, 3.3 and 18.7), and to almost 20-fold at 201 to 300 g per day (95 percent confidence limits, 6.1 and 6.2). For provoked seizures, the odds ratios were lower and statistically significant only above 200 g per day (odds ratio, 10.1; 95 percent confidence limits, 2.3 and 43.8 at 201 to 300 g per day; odds ratio, 7.4; 95 percent confidence limits, 1.8 and 30.5 above 300 g per day). Among ex-drinkers (abstention greater than or equal to 1 year), no increased risk was detected. Alcohol withdrawal was not associated with the onset of seizures in this study; 16 percent of first seizures in drinkers fell outside the conventionally defined withdrawal period, and the remainder exhibited a seemingly random timing after the last drink. We conclude that the relation of seizures to alcohol use is dose dependent and appears to be causal, and that seizures can be interpreted as a disorder induced by the ingestion of alcohol, independently of alcohol withdrawal.
Quantitative material properties for meteoroids from interplanetary dust particles

Abstract Low-porosity, high-density meteoroids could be more common than porous aggregate meteoroids because hydration of porous aggregates initially embedded in ice is relatively fast even at low temperatures causing the collapse to partially and fully hydrated aggregates. Efficient hydration was possible because the matrix of such aggregates is dominated by highly metastable ferromagnesiosilica dust. Measured H/Fe ratios in comet dust support partial dust hydration. Aggregate densification is expressed in different shapes of the meteor light curve ranging from a humped (compound) to a classical-shape for massive hydrated meteors.