cssi/SciSciGPT-SciSciNet huggingface dataset:
Unraveling the surface glycoprotein interaction network by integrating chemical crosslinking with MS-based proteomics.

The cell plasma membrane provides a highly interactive platform for the information transfer between the inside and outside of cells. The surface glycoprotein interaction network is extremely important in many extracellular events, and aberrant protein interactions are closely correlated with various diseases including cancer. Comprehensive analysis of cell surface protein interactions will deepen our understanding of the collaborations among surface proteins to regulate cellular activity. In this work, we developed a method integrating chemical crosslinking, an enzymatic reaction, and MS-based proteomics to systematically characterize proteins interacting with surface glycoproteins, and then constructed the surfaceome interaction network. Glycans covalently bound to proteins were employed as “baits”, and proteins that interact with surface glycoproteins were connected using chemical crosslinking. Glycans on surface glycoproteins were oxidized with galactose oxidase (GAO) and sequentially surface glycoproteins together with their interactors (“prey”) were enriched through hydrazide chemistry. In combination with quantitative proteomics, over 300 proteins interacting with surface glycoproteins were identified. Many important domains related to extracellular events were found on these proteins. Based on the protein–protein interaction database, we constructed the interaction network among the identified proteins, in which the hub proteins play more important roles in the interactome. Through analysis of crosslinked peptides, specific interactors were identified for glycoproteins on the cell surface. The newly developed method can be extensively applied to study glycoprotein interactions on the cell surface, including the dynamics of the surfaceome interactions in cells with external stimuli.
DNA and Connectivity

The Human Genome Project started in 1988. By 2003 the mapping of the human genome—listing the roughly 3 billion ‘letters’ that make up a person’s DNA—was complete. Since then there have been significant developments in the technology of DNA sequencing. A major development in population genetics has been strides in uncovering and deciphering ancient DNA material, in labs in the US, Germany and the UK (Reich 2018). Developments in African DNA research are adding major data to human genome understanding. Considering that about 99 percent of our evolutionary history occurred in Africa, Africa holds the vast majority of our genetic diversity, which African researchers are now mapping.
Rational design of guiding elements to control folding topology in i-motifs with multiple quadruplexes

Nucleic acids are versatile scaffolds that accommodate a wide range of precisely defined operational characteristics. Rational design of sensing, molecular computing, nanotechnology, and other nucleic acid devices requires precise control over folding conformations in these macromolecules. Here, we report a new approach that empowers well-defined conformational transitions in DNA molecular devices. Specifically, we develop tools for precise folding of multiple DNA quadruplexes (i-motifs) within the same oligonucleotide strand. To accomplish this task, we modify a DNA strand with kinetic control elements (hairpins and double stranded stems) that fold on a much faster timescale and consequently guide quadruplexes toward the targeted folding topology. To demonstrate that such guiding elements indeed facilitate formation of the targeted folding topology, we thoroughly characterize the folding/unfolding transitions through a combination of thermodynamic techniques, size exclusion chromatography (SEC) and small-angle X-ray scattering (SAXS). Furthermore, we extend SAXS capabilities to produce a direct insight on the shape and dimensions of the folded quadruplexes by computing their electron density maps from solution scattering data.
AI Principles in Identifying Toxicity in Online Conversation: Keynote at the Third Workshop on Fairness, Accountability, Transparency, Ethics and Society on the Web

Jigsaw’s Perspective API aims to protect voices in online conversation by developing and serving machine learning models that identify toxicity text. This talk will share how the team behind Perspective thinks about the issues of Fairness, Accountability, Transparency, Ethics and Society through the lens of Google’s AI Principles. For the Perspective team, building technology that is fair and ethical is a continuous, ongoing effort. The talk will cover concrete strategies the Perspective team has already used to mitigate bias in ML models as well as new strategies currently being explored. Finally, with examples of how Perspective is being used in the real world, the talk will show how machine learning, combined with thoughtful human moderation and participation, can help improve online conversations.
Prognostication and Treatment of Burkitt Lymphoma in the Modern Era

Introduction Burkitt lymphoma (BL) is an ultra-aggressive B-cell lymphoma which represents ~1% of adult and ~30% of pediatric lymphomas.1 Apart from the sporadic variant predominant in the United States (US), BL may occur as immunodeficiency-associated or endemic variants. BL is curable in most patients with short-course, dose-intense immunochemotherapy. Molecular underpinning of BL has been well understood, but not yet translated into targeted therapy. About 90% show MYC rearrangement with an immunoglobulin gene (the classical IGH-MYC t(8;14), IGK, or IGL) but otherwise BL has fewer karyotypic abnormalities than other high-grade lymphomas. Commonly mutated genes include the centroblastic transcription factor TCF3 (25%, activating mutations) or its inhibitor ID3 (60%, inactivating mutations), cell cycle regulators CCND3 (30%) and CDKN2A/B (10%), as well as TP53 (35%).2 Of note, tonic PI3K-AKT-mTOR signaling contributes to BL sustained cell survival. The prognostic impact of specific molecular features remains undefined.
Black Lives Matter, COVID-19, and Political Opportunities:: Understanding Social Movement Expansion through Political Process Theory

In the summer of 2020, while mired in the COVID-19 pandemic, the United States experienced an unprecedentedly massive wave of protests led by the Black Lives Matter movement. Given the novelty of this upswell and the lack of a clear precedent thereof, there does not yet exist much scholarly analysis into why and how this movement expanded as significantly as it did or what developmental routes it may take as in the future. My research seeks to remedy this gap by employing the political process theory of social movement activity to interpret how the COVID pandemic increased opportunities for insurgent activity, how Black Lives Matter was in a prime position to take advantage of those opportunities, and how the movement can and should approach its future development to retain the support and leverage it accumulated during the 2020 protests. Through informal qualitative analysis rooted in the political process model, I suggest that COVID led to greater public recognition of institutional maladies in the United States, which Black Lives Matter was able to channel toward protest activity thanks to the low-cost, high-reward membership system inherent in its non-hierarchical structure and tactful use of social media. I then briefly consider different developmental paths that Black Lives Matter may take and assert that carefully implemented attempts at formalization will allow the movement to retain its organizing potential regardless of any volatile external opportunities.
A Comprehensive Summary of Systematic Reviews on Sports Injury Prevention Strategies

Background:A large volume of systematic reviews and meta-analyses has been published on the effectiveness of sports injury prevention programs.Purpose:To provide a qualitative summary of published ...
Characteristics and Behavior of Pacific Coast Tidal Inlets

All generally available navigation charts and tidal data were critically examined for 48 tidal inlets, lagoon, and bays along the coasts of California, Oregon, and Washington to determine the tidal prism and throat area of the inlets. Twenty-five of the inlets yielded data which were considered reliable, and a relationship between tidal prism and inlet area was formulated. All 25 inlets, except one, were originally in erodible material although in numerous instances the inlets now have been stabilized by jetties. Some inlets depart radically from a fairly good relationship between tidal prism and throat area for most inlets. The probable reason for this departure is examined. Whether or not an inlet is always open, always closed, or open on occasions, appears to be related to the ratio of wave power to tidal power. An approximate closure criterion is presented from an analysis which considered 46 of the inlets.
Steganography and collusion in cryptographic protocols

Steganography, the hiding of covert messages inside innocuous communication, is an active area of cryptographic research. Recent research has shown that provably undetectable steganography is possible in a wide variety of settings. We believe that the existence of such undetectable steganography will have far reaching implications. In this thesis, we investigate the impact of steganography on the design of cryptographic protocols. In particular, we show that all existing cryptographic protocols allow malicious players to collude and coordinate their actions by steganographicly hiding covert messages inside legitimate protocol traffic. Such collusion is devastating in many settings, and thus we argue that its elimination is an important direction for cryptographic research. Defeating such steganographic collusion requires not only new cryptographic protocols, but also a new notion of protocol security. Traditional notions of protocol security attempt to minimize the injuries to privacy and correctness inflicted by malicious participants who collude during run-tune. They do not, however, prevent malicious parties from colluding and coordinating their actions in the first place! We therefore put forward the notion of a collusion-free protocol which guarantees that no set of players can use the protocol to maliciously coordinate their actions. As should be expected, such a strong notion of security is very difficult to achieve. We show that achieving collusion-free security is impossible in a model with only broadcast communication and that even with physically private communication (e.g. physical envelopes) there are still many ideal functionalities that have no collusion-free protocols. Fortunately, under natural assumptions collusion-free protocols exist for an interesting class of ideal functionalities. Assuming the existence of trapdoor permutations, we construct collusion-free protocols, in a model with both broadcast messages and physical envelopes, for every finite ideal functionality in which all actions are public.
Students' Perceptions of and Preferences for Professors

We examined the similarity of students’ perceptions of and preferences for the behaviors of professors in three different disciplines. Undergraduate students who had taken a history, biology, or psychology class rated actual and ideal professors on 20 behaviors (e.g., disclosure of personal information). Students perceived psychology professors to be different than history and biology professors on several characteristics, despite similarity in student ratings of ideal preferences across these disciplines. We discuss implications for both professors and students regarding course evaluations and learning, respectively.
Introduction to the special issue on addiction health services: in memory of Douglas Longshore.

This is an Introduction to a special issue in memory of Douglas Longshore, a prominent researcher in the field of addiction health services. The findings from the ten papers in this issue are summarized and discussed within the context of Doug’s development as a researcher and the core themes from his work. Three core areas are addressed: (1) internal processes related to change among substance abusers, (2) processes related to ethnicity and gender, and (3) treatment effectiveness, particularly regarding interventions to reduce risk of HIV/AIDS among substance abusers. The implications for addiction health services are discussed with regard to the application of these themes to practice.
A shot in the arm: what a modern approach to Jacobson v. Massachusetts means for mandatory vaccinations during a public health emergency.

Introduction 1716 I. Background 1718 A. Protection of Public Health in Jacobson v. Massachusetts ... 1718 B. Strict Scrutiny and the Fundamental Right 1721 C. Individual Liberty and the Right to Refuse Medical Treatment 1725 D. Public Health Emergencies and the Model State Emergency Health Powers Act 1728 II. Narrowing Jacobson and Surviving Strict Scrutiny 1730 A. The Right to Refuse Vaccination as a Fundamental Right .... 1731 B. The Compelling Public Health Emergency 1733 C. Necessary Elements to Achieve Narrow Tailoring 1736 D. Less Restrictive, Less Effective Alternatives 1740 E. Limiting Statutory Exemptions 1742 III. Collateral Consequences of Narrowing Jacobson 1746 Conclusion 1749
Anatomical cross-sectional geometry and density distribution data base

Precise and detailed three-dimensional geometry of the human body and mass density distribution of various tissues and skeletal structures are essential in many aspects of research related to biomechanics. This paper describes a data base consisting of such quantities. The computerized tomographic technique is used to derive this data base. The experimental procedure is described first, followed by a description of the structure of the data base, concluding with suggestions for possible applications of the data base.
An rRNA mutation identifies the apicoplast as the target for clindamycin in Toxoplasma gondii.

Toxoplasma gondii is a protozoan sensitive to several inhibitors of prokaryotic translation (e.g. clindamycin, macrolides and tetracyclines). A priori, two prokaryotic-like organelles, the 'apicoplast' (a non-photosynthetic plastid) and the mitochondrion, are likely targets for these drugs. Without using overt mutagenesis, we selected two independent clones (ClnR-4 and ClnR-21) with strong and stable clindamycin resistance. Several lines with substantial but lower levels of resistance were also isolated with (XR-46) or without (ClnR-23) overt mutagenesis. The ClnR-4 and ClnR-21 mutants uniquely possess a G-->U point mutation at position 1857 of the apicoplast large-subunit rRNA, whereas no mutation was identified in this region for ClnR-23 or XR-46. Position 1857 corresponds to position 2061 in Escherichia coli where it is predicted to bind clindamycin. The mutation is present in all the apicoplast rDNA copies (an estimated 12 per organelle), indicative of a strong selective advantage in the presence of clindamycin. In the absence of drug, however, such a mutation is unlikely to be neutral, as the G is a critical contributor to the transpeptidation reaction and absolutely conserved in all kingdoms. This may explain why ClnR-4 shows a slight growth defect in vitro. These mutants provide direct genetic evidence that apicoplast translation is the target for clindamycin in Toxoplasma. Further, their sensitivity profiles to other antibiotics specific for the large ribosomal subunit (macrolides and chloramphenicol) and, intriguingly, the small subunit (doxycycline) argue that these drugs also target the apicoplast ribosome.
Convergence of digital humanities and digital libraries

Purpose – Digital humanities (DH) has become a much discussed topic among both humanities scholars and library professionals. The library and information science (LIS) community has taken efforts in providing new facilities and developing new services to meet humanities scholars’ changing research behaviors and needs employing digital tools and methods. How to effectively collaborate with the DH community has been a challenging task to LIS in their digital library (DL) development endeavors. The purpose of this paper is to discover productive ways for LIS to support DH scholarship, specifically, what DL components, including content, technology, and service, should and could be developed for digital humanists. Design/methodology/approach – As an initial effort of the Digital Humanities Interest Group at University of California, Irvine Libraries, the examination is primarily based on a cross-boundary environmental scan in both DH and DL fields. The environmental survey includes both a literature review an...
Molecular and histopathologic predictors of distant failure in endometrial cancer.

Abstract A case-cohort study was designed to correlate various histopathologic and molecular variables with distant failure in endometrial cancer by analyzing phenotypic and molecular indices in hysterectomy specimens. From an overall population of 283 patients with endometrial cancer, we selected a cohort including all 49 patients who experienced any recurrence and 76 randomly chosen patients without recurrence. Expression of nuclear proliferating cell nuclear antigen (PCNA), MIB-1 (a marker of cell proliferation), and p53 was determined with digital image analysis, and cell membrane HER-2/neu and bcl-2 were quantitated visually. Ploidy and DNA indices were determined with flow cytometry. Overall, 6 immunohistochemical and 11 flow cytometric cases were eliminated because of technical inadequacies. Distant failures were defined as primary recurrences that developed outside the pelvis or vagina. Median follow-up was 91 months. Distant failures occurred in 13% of the patients. Cervical stromal invasion, positive adnexae, myometrial invasion >50%, positive lymph nodes, positive peritoneal cytology, lymphovascular invasion, grade 3 histology, nonendometrioid subtype, p53 >33%, strong HER-2/neu membranous staining, aneuploidy, S-phase fraction ≥9%, proliferative index ≥14%, and DNA index ≥1.5 significantly ( P P P P =0.001) as cogent predictors of distant failures. Only 3% of patients without any of these three predictors developed distant failures compared with 36% of those with at least one of the three ( P
Stress birefringence in amorphous polymers under nonisothermal conditions

The relationship of birefringence to stress in an amorphous polymer was studied, with emphasis on conditions of high stress and rapid cooling. The latter (nonisothermal) conditions are important in connection with studies of polymer processing operations. Polystyrene was pulled at a constant elongation rate (0.075 to 2 sec−1 in the present and related work) under both isothermal conditions (in the range 120 to 157°C) and nonisothermal conditions (with cooling rates in the range 0.6 to 1.7°C/sec). Generally we conclude that stress in proportional to birefringence under a wide range of conditions, except that a nonlinear regime appears at stresses higher than about 107 dyn/cm2. In this regime, stress increases more rapidly with deformation than does birefringence.
SURFACE POTENTIAL AND PHOTO‐ADSORPTION ONTO SEMICONDUCTORS

— A theory of photo-adsorption onto semiconductors is developed using the kinetic expressions and the relations for steady state carrier concentrations in terms of the quasien Fermi levels. Expressions are derived which emphasize the importance of the surface potential. In particular it is shown that a significant quantity is the ratio of the surface potential to a critical quantity, Ysc. An expression for the latter is given and it is shown that photoadsorption occurs if the ratio is greater than unity while desorption occurs if the ratio is less than unity. The theory also suggests a useful graphical representation of the effects of impurities and surface potential on adsorption.
Plasticity of brittle epoxy resins during debonding failures

A remarkably high degree of plasticity in brittle epoxies during debonding failures is reported. The plasticity is exhibited by the presence of ridges on the debonded surfaces having a width and height above the general level of these surfaces of the order of 100 nm. The surfaces of the more rigid substrates from which the debonding has occurred, by contrast, are smooth after debonding. The ridges have been found in several forms: in more or less straight rows parallel to the debonding fracture direction; as irregularly-shapes rings or craters, probably formed from secondary crack growth; as paraboloids, which also seem to be related to secondary crack growth; and as serpentine rows more or less perpendicular to the debonding fracture direction. This behaviour has been exhibited by various epoxy formulations. The 100 nm widths and heights for the ridges suggest that during debonding, plastic deformation has occurred rather uniformly in the epoxy to a depth below the interface of this order. This behaviour is in contrast to the simple notion of brittle fracture, in which atoms or molecules separate across planes in an elastically strained body. It differs also from the bulk fracturing process with these resins, in which a smaller amplitude, more random ridge and groove texture, referred to as the “basic longitudinal” or “fingering” texture, is seen.
Efficacy and safety of balloon valvuloplasty as a treatment of choice for pulmonary stenosis in children and adolescents

Introduction. Pulmonary artery stenosis (PS) is a congenital heart defect which occurs in 10% of all congenital heart defects. Pulmonary balloon valvuloplasty (BVP) has been the treatment of choice of PS over the last 30 years. Objective. The purpose of this study was to evaluate the efficacy of this method based on middle-term hospital follow-up, and safety of BVP based on our experience. Methods. The study included 88 patients diagnosed with PS. The patients were divided into three groups based on the severity of the disease. Also, they were divided into two age groups in order to analyze the frequency of complications. Hemodynamic measurements and echocardiography results were recorded before, 24-36 hours after BVP and at the end of follow-up. Results. The studied group involved patients of average age 3.75±4.3 years (20 days to 17 years). Immediately after BVP a significant decrease of pressure gradient across the pulmonary valve (PV) was recorded in all patients; this result was similar in all 3 groups of patients regardless of the severity of stenosis (p<0.001). Complications of BVP occurred most commonly in children up to 12 months of age (ventricular tachycardia 4.5% and supraventricular tachycardia 6.8%). Pulmonary valve insufficiency after dilatation occurred in 6.6% of cases, and was most common in children aged up to 12 months. In 87 (98.9%) patients BVP was a definitive solution, and a significant residual stenosis was not recorded during follow-up. Conclusion. BVP is a safe and effective procedure in the treatment of isolated PS in children, regardless of the severity of stenosis but also regardless of patients’ age.
Elementary queueing theory based on possibility theory

Abstract We consider a queueing system with multiple parallel servers, finite or infinite system capacity and calling source, but whose arrivals and service completions are governed by a possibility distribution. Changes in the number of customers in the system is modeled by a transition matrix Ω and powers of Ω, under max-min product, produce (if it converges) the steady-state possibility distribution. Results are applied to the machine servicing problem to determine the most economical size of the repair crew.
Hydrogen-deuterium exchange in fused-silica capillary columns.

Abstract Ketones deuteriated α to the carbonyl have been observed to undergo significant isotope exchange on fused-silica capillary columns during gas chromatography—mass spectrometry. The residence time of the compounds on the column was found to influence the extent of isotope exchange. The degree of exchange was examined using a variety of columns and the isotope exchange was found to occur even with brand new columns. Conversion of the keto compounds into the methyloxime derivatives resulted in retention of the “correct” isotope content during gas chromatography—mass spectrometry.
Small mammal diversity along elevational gradients in the Philippines: an assessment of patterns and hypotheses

1 It is widely accepted that tropical lowland rain forest holds the greatest diversity of organisms, and it is often implied that this general pattern is also true for virtually all individual higher-level taxa. Standardized elevational transect surveys of non-flying small mammals (Insectivora and Rodentia) on geologically old, species-rich islands in the Philippines consistently show maximum diversity and relative abundance in upper montane/lower mossy forest at 1500–2200 m, often exceeding lowland species richness and relative abundance by a factor of three or more. 2 On mountains where maximum elevation exceeds 2000 m, there is a decline in species richness above about 1500–2000 m, yielding a curvilinear pattern of species richness along the elevational gradient. The peak in species richness occurs at the area of transition from montane to mossy forest, which is also the point at which rainfall probably peaks. In parallel with species richness, relative abundance of small mammals in the Philippines also increases from the lowlands to 1500–2200 m, increasing by a factor from two to 10. 3 Twelve hypotheses concerning patterns of diversity along elevational gradients, plus the null hypothesis, are evaluated. The null hypothesis of no variation and the hypotheses that maximum diversity is in the lowlands, that diversity is highest in areas of least perturbation, and that diversity increases with increasing area, are rejected. There is weak or ambiguous support for the hypotheses that diversity is greatest in areas of community interdigitation, that diversity is highest in the area of highest productivity, that diversity is correlated with habitat complexity, and that diversity is correlated with habitat diversity. There is strongest support for the hypotheses that diversity is correlated with annual rainfall, with total abundance of individuals in the community, with food resource diversity, with areas of reduced competition from other organisms, and with areas characterized by high rates of speciation. 4 Causality is difficult to evaluate because many hypotheses make non-exclusive predictions, they probably represent non-independent aspects of causal factors (in other words, there is much interaction among the processes highlighted by the various hypotheses), and they represent the range from proximate to ultimate and from descriptive to causal. All the hypotheses probably represent phenomena that exist in nature, but few (or none) represent phenomena found in all taxa. The primary challenge in the future will not be simply to accept or reject individual hypotheses, but rather to determine the circumstances under which the various causal factors are most important, how they interact, and how they can be combined into a more comprehensive and general multi-factorial model.
Quark imprisonment and vacuum repulsion

We describe a classical field theory in which infinitely long-range forces are present. These forces do not stem from a direct interaction among particles. They have their origin in a rather peculiar phenomenon, which we call vacuum repulsion.
Periurethral collagen for urinary incontinence after gender reassignment surgery

We report on 2 patients, one female and one male transsexual; in both, Type III stress urinary incontinence developed after gender reassignment surgery. Both patients were treated by periurethral injection of gluteraldehyde cross-linked collagen resulting in a marked symptomatic improvement in association with a significant rise in abdominal leak point pressures. We believe these are the first reported cases of collagen injection being used for urinary incontinence after gender reassignment surgery.
Sustained Bidwell Afterimages: Effects of Disc Rotation Speed, Color-Pulse Chromaticity, and Color-Pulse Luminance*†

A sustained complementary hue may be obtained with a rotating black–white disc and pulses of chromatic light. Effects of disc rotation speed and of the chromaticity and luminance of the color pulse are described. The disc. observed at 11 speeds from 10 through 110 cps had a black and white sector. At the sector boundary there was an aperture through which red, yellow, green, blue, or purple light (filters equated for luminous transmittance) was pulsed for 3% of each cycle, followed by the white half cycle. Eleven observers made Munsell matches (total: 4995) to these lights, which were presented at three luminances. Complementary matches occurred 48% of the time, matches similar to the hues of the projected lights—33%, neutral matches—19%. There were systematic hue shifts around two pairs of stable points in the hue circle, as functions of disc rotation speed. The predominance of complementary matches over similar-hue matches varied with color-pulse chromaticity and luminance, and with disc speed.
Intoxication of Aphelenchus Avenae By Ethylene Dibromide

The exposure of Aphelenchus avenae to low concentrations of ethylene dibromide results in a very small conversion of the halide by the nematodes just preceding death. Using ethylene dibromide 1, 2-C14, two primary products are characterized. These are ethylene ( ~5 % ) and O-acetylserine (~95%). These products account for all of the ethylene dibromide converted. The radiolabel in O-acetylserine resides in the carbons of the acetyl moiety. These transformations are taken to indicate two primary modes of intoxication of the nematodes. These are formulated as: (1) a direct reaction of the halide with an iron center in the respiratory sequence and (2) the substitution of a serine at the active site of an esterase or protease.
Flutter of a Fan Blade in Supersonic Axial Flow

An application of a simple aeroelastic model to an advanced supersonic axial flow fan is presented. Lane's cascade theory is used to determine the unsteady aerodynamic loads. Parametric studies are performed to determine the effects of mode coupling, Mach number, damping, pitching axis location, solidity, stagger angle, and mistuning. The results show that supersonic axial flow fan and compressor blades are susceptible to a strong torsional mode flutter having critical reduced velocities which can be less than one.
MARINE RESERVES ENHANCE ABUNDANCE BUT NOT COMPETITIVE IMPACTS OF A HARVESTED NONINDIGENOUS SPECIES

Marine reserves are being increasingly used to protect exploited marine species. However, blanket protection of species within a reserve may shelter nonindigenous species that are normally affected by harvesting, intensifying their impacts on native species. I studied a system of marine reserves in the San Juan Islands, Washington, USA, to examine the extent to which marine reserves are invaded by nonindigenous species and the con- sequences of these invasions on native species. I surveyed three reserves and eight non- reserves to quantify the abundance of intertidal suspension-feeding clam species, three of which are regionally widespread nonindigenous species (Nuttallia obscurata, Mya arenaria, and Venerupis philippinarum). Neither total nonindigenous nor native species' abundance was significantly greater on reserves. However, the most heavily harvested species, V. philippinarum, was significantly more abundant on reserves, with the three reserves ranking highest in Venerupis biomass of all 11 sites. In contrast, a similar, harvested native species (Protothaca staminea) did not differ between reserves and non-reserves. I followed these surveys with a year-long field experiment replicated at six sites (the three reserves and three of the surveyed non-reserve sites). The experiment examined the effects of high Venerupis densities on mortality, growth, and fecundity of the confamilial Protothaca, and whether differences in predator abundance mitigate density-dependent effects. Even at densities 50% higher than measured in the field survey, Venerupis had no direct effect on itself or Protothaca; only site, predator exposure, and their interaction had significant effects. Analyses incorporating environmental variables tracked at each site indicated that crab biomass most heavily influenced clam responses, causing lower growth of both species and higher mortality of Venerupis, whose annualized loss rate was 50% when exposed to predators. A laboratory prey choice experiment indicated that Cancer productus ,a ninfluential intertidal crab predator, favored small adult Venerupis at least 1.7 times over Protothaca. Venerupis' high susceptibility to excavating crab and human pred- ators, as well as its faster growth compared to Protothaca can be explained by its shallower burial depth. By growing quickly and residing near the surface, Venerupis apparently ab- sorbs the brunt of harvest pressure while Protothaca maintains high biomass even outside of reserves.
Gold, silver, and the Glorious Revolution: arbitrage between bills of exchange and bullion1

Between i688 and I700 England's monetary system suffered a deep crisis. Coins were clipped and silver was exported. The price of gold coins increased by 40 per cent while the value of the pound collapsed on the international exchanges. These conditions resulted from a process of arbitrage between bills of exchange and bullion following the exogenous shock of financing England's entry into the Nine Years War in i689. Arbitrage between bills of exchange and bullion rather than arbitrage between gold and silver formed a mechanism whereby shocks to international exchange rates were transmitted to England's monetary stock. This article presents market behaviour consistent with arbitrage between bills and bullion that marks a degree of international market integration during the late seventeenth century which has been statistically verified only for the eighteenth century. The micro-level financial innovations necessary for this successful arbitrage are then examined in the actions of a prominent London banker. A result of arbitrage between bills and bullion was an international flow of one metal with no offsetting flow of the other. Although other authors have considered the interplay between bills and bullion at this time, they do not develop explicitly the interaction of the three markets in an explanatory framework.2 Hence, the period has lacked a single, consistent framework for reconciling times of gold inflows into England with times of silver outflows. Clarifying how international markets transmitted shocks explains the crisis that followed the Glorious Revolution and led to permanent changes in England's monetary regime. England had been on a silver standard for centuries prior to the i69os. In response to gold's high price and silver's massive exportation, Parliament legally set a unit of account value for gold coins which marked the beginning of a bimetallic regime that lasted for over a century.3 The results of arbitrage were a precondition for this political action.4 Along with a bimetallic standard (both silver and gold
Wind-Tunnel Testing and Modeling of a Micro Air Vehicle with Flexible Wings

The field of micro air vehicles is relatively immature; consequently, high-fidelity simulations do not yet exist for a generic aircraft. The fidelity of flight dynamic simulations is closely correlated to the reliability of models representing the vehicle's aerodynamic and propulsion characteristics in the entire flight envelope, including the nonlinear region. This paper discusses wind-tunnel experiments performed to investigate the aerodynamic and mechanical characteristics of micro air vehicles with flexible wings in different conditions of propeller type, motor power, and elevator deflections. Visual image correlation was used to measure the deformation of the flexible wings to quantify general features such as variations in aerodynamic and geometric twist angle. Aerodynamic and propulsion results were used to formulate empirical models of the relevant coefficients in the form of multiple linear regressions and to estimate the effectors' functional dependencies and interactions. High-order nonlinear interactions were confirmed between the coefficients of lift, drag, and pitching moment with the independent variables. The rates of the dependencies with elevator deflections and angle of attack were found, to some extent, to be motor voltage and dynamic pressure dependent, evincing a strong coupling with the propeller speed.
Enhancement in mechanical properties of concrete due to blended ash

This study was carried out to evaluate the effects of blended ash mixture on mechanical properties of concrete. In this study two reference mixtures were used. One of the mixtures was a no-fly ash mixture, and the other mixture contained 35% unblended Class C fly ash. Additional mixtures were composed of three blends of Class C and Class F fly ash while maintaining a total fly ash content of 40% of the total cementitious materials. Mechanical properties such as compressive strength, tensile strength, flexural strength, and modulus of elasticity were determined as a function of age ranging from 1 to 91 days. The results showed that blending of Class F fly ash with Class C fly ash showed either comparable or better results compared to either the reference mixture without fly ash or the unblended Class C fly ash concrete mixture at a fly ash concentration of 40% of total cementitious materials.
Reactivation and aging of diphenyl phosphoryl acetylcholinesterase.

Abstract Acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7) is readily inhibited by 10 −5 M diphenylphosphorochloridate even though the inhibitor hydrolyzes in a few seconds. The fluoridate is a much weaker inhibitor. The inhibited enzyme, diphenyl phosphoryl enzyme spontaneously recovers only about 50% of its activity with a half time of about 17 min at pH 7.0 and 6 min at pH 8.0. The fact that only 50% of the original activity returns is due to aging. The rates of reactivation and aging can be very greatly increased by a few percent of an organic solvent. Depending on the solvent even 1% may increase the rates by a factor of 5 or 6. The highest increase in rate was 70-fold. Quarternary NH 4 + also increases the rates. Organic solvents and NH 4 + also accelerate the reactivation of the much more stable diethyl phosphoryl enzyme derivative.
Assessing Fractionated Spacecraft Value Propositions for Earth Imaging Space Missions

Fractionated spacecraft consist of physically independent, “free-flying”modules composed of various subsystems. Thus, a fractionated spacecraft might consist of one module providing power generation and storage, another module providing communications, another module providing the payload functions, and so on. Fractionated spacecraft are of particular interest for earth imaging missions because of their ability to physically decouple pointing-intensive payloads from subsystems not requiring such strict pointing. This in turnmay enable fractionated spacecraft to have a lower life cycle cost and longer mission lifetime relative to a comparable monolithic spacecraft, for a given performance level. In this research, fractionated architectures were assessed using a custom-built spacecraft model, and their respective life cycle costs were quantified using a stochastic life cycle simulation and parametricmodel. Results demonstrate that, relative to a comparablemonolithic spacecraft, fractionated spacecraft can have a stronger value proposition through the attainment of a lesser life cycle cost for an equal if not longer mission lifetime than comparable monoliths, for high-resolution earth imaging missions.
Desorption via electronic transitions: Fundamental mechanisms and applications

Abstract Photon- or electron stimulated desorption (PSD or ESD) from solid surfaces results from the excitation of localized surface or adsorbate electronic states. The fundamental issues include the identification of electronic excitations with lead to desorption, the mechanisms for localization of the excitation, and the competition between nuclear motion and quenching of the excited states. We discuss these basic issues and their role in understanding stimulated desorption of molecular adsorbates from metal surfaces, and the desorption processes important in electron or photon bombardment of ionic solids. We focus on simple systems which serve as useful prototypes: CO chemisorbed on metals for adsorbate systems, and alkali-halides tor ionic solids. We review the current understanding of PSD and ESD for these systems, including a variety of very recent results. Finally, we discuss an example of the application of ESD to provide precise control of surface chemistry in the synthesis of electronic materials.
Kronos: a multiwavelength observatory for mapping accretion-driven sources

ABSTRACT Kronos is a multiwavelength observatory proposed as a NASA Medium Explorer. Kronos is designed to make use of the natural variability of accreting sources to create microarcsecond-resolution maps of the environments of supermassive black holes in active galaxies and stellar-size black holes in binary systems and to characterize accretion processes in Galactic compact binaries. Kronos will obtain broad energy range spectroscopic data with co-aligned X-ray, ultraviolet, and optical spectrometers. The high-Earth orbit of Kronos enables well-sampled, high time-resolution observations, critical for the innovative and sophisticated methods that are used to understand the accretion flows, mass outflows, jets, and other phenomena found in accreting sources. By utilizing reverberation mapping analysis techniques, Kronos produces advanced high-resolution maps of unprecedented resolution of the extreme environment in the inner cores of active galaxies. Similarly, Doppler tomography and eclipse mapping techniques characterize and map Galactic binary systems, revealing the details of the physics of accretion processes in black hole, neutron star, and white dwarf binary systems. The Kronos instrument complement, sensitivity, and orbital environment make it suitable to aggressively address time variable phenomena in a wide range of astronomical objects from nearby flare stars to distant galaxies. Keywords: Black holes, gravitational accretion, ultraviolet spectroscopy, X-ray spectroscopy, tomography
DNA strand scission by the antitumor protein neocarzinostatin.

Abstract The antibiotic protein, neocarzinostatin, induces the scission of DNA strands in vivo and in vitro . HeLa cell DNA prelabelled with [ 14 C] thymidine is cut into large pieces with a peak at 80–90S when cells are incubated with 0.5 to 5.0 μg/ml of highly purified neocarzinostatin. Incubation of the antibiotic (0.5 μg/ml) with [ 3 H] SV40 DNA in the presence of 2-mercaptoethanol results in the conversion of superhelical DNA I to nicked circular duplex DNA II. At high levels of drug, smaller fragments of linear DNA are produced. Strand breaks are detected in both neutral and alkaline sucrose gradients, indicating that drug susceptibility is not due to alkali-labile bonds.
Ruptured gel-filled silicone breast implants: sonographic findings in 19 cases.

The purpose of this study was to describe and illustrate the sonographic appearances of 19 ruptured silicone gel breast implants.We retrospectively reviewed the sonograms of 16 patients with 19 ruptured silicone gel implants from two institutions. The ruptured implant was confirmed at surgery in 17 cases and by mammographic and clinical findings of a ruptured implant combined with biopsy findings of a silicone granuloma in two cases. Breast sonograms were available for review in all patients. The clinical presentation of each patient was recorded. The sonograms and mammograms were reviewed, and the findings were correlated with the surgical findings. In 16 of the 19 ruptured implants, mammographic findings suggested rupture, including lobulation of the contour of the implant and/or silicone extrusion into the breast parenchyma or axilla. In two ruptured implants, mammographic findings were normal, and in one case, no mammogram was available. In those three patients, palpable masses and clinical findings w...
Quantitation of Dihydropyrimidine Dehydrogenase Expression by Real-Time Reverse Transcription Polymerase Chain Reaction

Several recent studies have reported a correlation between intratumor dihydropyrimidine dehydrogenase (DPD) messenger RNA (mRNA) levels and sensitivity to 5-fluorouracil (5-FU). However, significant tissue requirements and labor-intensive methodology have limited the large-scale studies necessary for statistical validation. In addition, the semiquantitative results obtained by these methods further limit their application. We have developed a real-time reverse transcription-PCR (RT-PCR) assay, based on TaqMan fluorescence methodology, capable of rapid and accurate quantitation of DPD mRNA levels in biopsy-sized tissue samples. Results obtained with this approach indicate a linear dynamic range of 10(8)-10(3) DPD mRNA copies, with an intra-assay variation of <5%. We evaluated the data using three different methods (absolute standard curve, relative standard curve, and comparative C(T)) and show them to be equivalent. This RT-PCR assay was validated by quantitative comparison to Northern blot analysis in five tissues. In addition, analysis of 18 colorectal tumor and liver tissue specimens demonstrated a significant correlation (r(2) = 0.90) between DPD enzyme activity and mRNA levels. This method provides the first high-throughput, reproducible, and sensitive technique capable of determining DPD mRNA expression levels in nanogram amounts of total RNA.
A cluster of transcribed sequences between the Pb and Ob genes of the murine major histocompatibility complex.

Abstract The region of the murine major histocompatibility complex (MHC) between the Pb (A beta 3) and Ob (A beta 2) genes controls the expression of an intracellular complex named the LMP (low molecular weight polypeptide) complex. DNA probes for at least seven different genes mapping to this region were isolated. These hybridize to a minimum of eight different transcripts ranging from approximately 1.3 to 3.7 kilobases (kb). The deduced amino acid sequences of the corresponding cDNAs indicate that three of these genes are new members of the MHC class II gene family. These genes are transcribed in a tissue-specific pattern similar to that of the traditional class II genes. Two of the remaining four genes, HAM1 and HAM2, are homologous to one another and to a family of eukaryotic and prokaryotic transport proteins and may be involved in antigen processing. The tissue distribution of HAM1 transcripts is consistent with its proposed role in class I-restricted antigen processing, whereas HAM2 transcription appears more restricted and may be involved in antigen processing for class II-restricted T cells. The HAM2 gene may produce two differentially spliced transcripts. The identity of the remaining two genes is not known. Analyses of transcript sizes, tissue distribution, sequence, and genetic mapping data suggest that none of these genes code for LMP antigens.
Aging, Agency, and Gwembe Tonga Getting By

Using a political ecology framework to explore the gendered nature of extended family support networks for the elderly, this article reveals the ways that older women and men negotiate their social and material worlds in the context of extreme ecological and economic conditions. The historical processes that shape the social and material worlds in which these elders move include development induced resettlement, postcolonial politics and economics, and catastrophic chronic illness and mortality of children. Drawing from ethnographic research from 1994 through 2008, the article explores how people living in economically and ecologically dire circumstances manage their social and material worlds to the best of their ability.