cssi/SciSciGPT-SciSciNet huggingface dataset:
Planning routes of continuous illumination and traversable slope using connected component analysis

This paper presents a method that applies connected component analysis to plan routes that keep robots continuously illuminated and on traversable slopes while reaching one or more goal locations. Such routes promise to extend the lifespan, range, and scientific return of solar-powered robots exploring environments with changing but predictable lighting conditions, particularly those of the Moon and Mercury. Maps of lighting and ground slope that describe these constraints in position and time are computed, and all distinct interconnected regions that have both direct sunlight and safe slope are found using connected component analysis. These three-dimensional connected components are pruned of roots that violate time constraints and branches that dead-end in discontinuous routes. Each component is the basis for a graph that includes all feasible routes from the initial time to the final time of that component. The shortest feasible route between a pair of start and goal positions within the same component is found using A* search and is characterized by its total length and average speed. Malapert Peak and Shackleton Crater, both near the Moon's South Pole, serve as examples throughout this paper due to their highly-relevant, dynamic, and predictable lighting caused by the Moon's motion relative to the Sun.
MICROFABRICATED NANOCHANNELS: NEW TOOLS FOR MOLECULAR MOTION CONTROL - Micro y nanocanales integrados: nuevas herramientas para control de movimiento molecular

This paper presents a review of work on the fabrication and use of nanochannels in silicon and polymers for the control of molecular transport. The method of Sacrificial Layer Lithography is reviewed and demonstrated for silicon and polymers. A novel technique for the productions of conical nanopores through a polymer membrane is also reviewed. Nanochannels and nanopores have many potential applications for drug delivery, immunoprotection of cell implants, blocking of globular proteins from biosensor surfaces, and diagnostic devices. All of these applications benefit from the more direct interactions of devices with biomolecules. Resumen — El presente trabajo presenta una revisi o n literaria sobre los m e todos de fabricaci o n de nanocanales en silicio y diferentes materiales polim e ricos; y su uso en control de transporte molecular. Se describe el m e todo “ Sacrificial Layer Lithography ” para silicio y pol i meros. Adicionalmente, una novedosa t e cnica para la producci o n de nanoporos c o nicos a trav e s de una membrana polim e rica es descrita. Los nanocanales y los nanoporos poseen diversas aplicaciones potenciales en la liberaci o n de drogas, en la inmunoprotecci o n de implantes celulares, el bloqueo de prote i nas globulares en la superficie de biosensores, y en dispositivos para diagn o stico. Todas estas aplicaciones se benefician de la interacci o n directa entre los dispositivos y las biomol e culas.
Are digital images allographic

Nelson Goodman's distinction between autographic and allographic arts is appealing, we suggest, because it promises to resolve several prima facie puzzles. We consider and rebut a recent argument that alleges that digital images explode the autographic/allographic distinction. Regardless, there is another familiar problem with the distinction, especially as Goodman formulates it: it seems to entirely ignore an important sense in which all artworks are historical. We note in reply that some artworks can be considered both as historical products and as formal structures. Talk about such works is ambiguous between the two conceptions. This allows us to recover Goodman's distinction: art forms that are ambiguous in this way are allographic. With that formulation settled, we argue that digital images are allographic. We conclude by considering the objection that digital photographs, unlike other digital images, would count as autographic by our criterion; we reply that this points to the vexed nature of photography rather than any problem with the distinction.
The relative importance of methanogenesis in the decomposition of organic matter in northern peatlands

Using an isotope-mass balance approach and assuming the equimolar production of CO2 and CH4 from methanogenesis (e.g., anaerobic decomposition of cellulose), we calculate that the proportion of total CO2 production from methanogenesis varies from 37 to 83% across a variety of northern peatlands. In a relative sense, methanogenesis was a more important pathway for decomposition in bogs (80 ± 13% of CO2 production) than in fens (64 ± 5.7% of CO2 production), but because fens contain more labile substrates they may support higher CH4 production overall. The concentration of CO2 produced from methanogenesis (CO2-meth) can be considered equivalent to CH4 concentration before loss due to ebullition, plant-mediated transport, or diffusion. Bogs produced slightly less CO2-meth than fens (2.9 ± 1.3 and 3.7 ± 1.4 mmol/L, respectively). Comparing the quantity of CH4 present to CO2-meth, fens lost slightly more CH4 than bogs (89 ± 2.8% and 82 ± 5.3%, respectively) likely due to the presence of vascular plant roots. In collapsed permafrost wetlands, bog moats produced half the amount of CO2-meth (0.8 ± 0.2 mmol/L) relative to midbogs (1.6 ± 0.6 mmol/L) and methanogenesis was less important (42 ± 6.6% of total CO2 production relative to 55 ± 8.1%). We hypothesize that the lower methane production potential in collapsed permafrost wetlands occurs because recently thawed organic substrates are being first exposed to the initial phases of anaerobic decomposition following collapse and flooding. Bog moats lost a comparable amount of CH4 as midbogs (63 ± 7.0% and 64 ± 9.3%).
The Molecular Biology of Nucleotide Excision Repair of DNA: Recent Progress

Recent years have witnessed significant progress towards understanding the molecular mechanism of nucleotide excision repair in living cells. Biochemical studies in Escherichia coli, and genetic and molecular studies in lower and higher eukaryotes have revealed an unexpected complexity suggesting interesting protein-protein and protein-DNA interactions. This review considers selected aspects of nucleotide excision repair in E. coli, Saccharomyces cerevisiae and mammalian cells, with a particular emphasis on new observations and on models that may provide explanations for the complexity evident from genetic and biochemical studies.
Conservatism and Staff Accounting Bulletin No. 108

Abstract This study examines whether firms with large conservative allowances for uncollectible accounts on their balance sheets make significant adjustments to increase net assets in response to Staff Accounting Bulletin No. 108 (SAB 108). To the extent adjustments are not made, we examine the qualitative reasons SAB 108 may have had a limited effect on these large conservative accounting estimates. In the year of enactment, SAB 108 required public companies to adjust material accumulations on the balance sheet that may have occurred prior to enactment of SAB 108 after considering all relevant quantitative and qualitative factors. Our archival results find that no firms made a SAB 108 adjustment and while sample firms tend to, at best, make small reductions to the allowance subsequent to SAB 108’s effective date, most sample firms continue to have potentially overestimated allowances several years later. To understand the qualitative forces underlying this finding, we interview key individuals involved in the financial reporting process and we survey experienced financial executives employed at our sample firms. The findings reveal that organizational forces favor conservatism because being over-reserved helps firms avoid income-decreasing surprises while being under-reserved appears careless. We conclude that conservatism remains a deeply engrained feature of accounting thought and practice, in contrast to recent emphasis by accounting standard setters on neutrality over conservatism.
The Uses of the Baobab Flower (Adansonia digitata L)

In the now extensive literature on the African baobab, the use of the flower is often overlooked or described as minimal. This paper presents a synthesis of the uses of the baobab flower that incorporates the results of my own fieldwork on the introduction and cultural significance of the baobab in Florida, the Caribbean, and Brazil. Fieldwork conducted over the past 30 years has involved locating, measuring, and photographing baobabs; observations on flowering and fruiting and such things as the size and shape of fruits and the number of seeds per fruit; and structured and unstructured interviews and community discussions to determine the cultural significance of the tree. In addition to publications and word of mouth, baobabs were also located by appeals to the public involving newspaper interviews and radio interviews. Although the uses of the baobab flower have yet to be documented in a manner comparable to other parts of the tree—especially the fruit, leaves, and bark—the present study shows it is far from being useless or of little use as some premature assessments would suggest. This initial summary is intended to encourage greater attention to the uses of the flower in the increasingly sophisticated research on the baobab that is now being done in Africa and elsewhere. En la literatura del baobab africano, hoy en dia extensa, el uso de la flor a menudo se pasa por alto o se describe como minimo. Este articulo presenta una sintesis de los usos de la flor del baobab que incorpora los resultados de mis estudios en el campo relativos a la introduccion y el significado cultural del baobab en Florida, el Caribe y en Brasil. El trabajo de campo realizado en los ultimos 30 anos se ha dedicado a localizar, medir y fotografiar baobabs; a hacer observaciones de la floracion y la fructificacion y de cosas como el tamano y la forma de los frutos y el numero de semillas por fruto; a llevar a cabo entrevistas estructuradas y no estructuradas, asi como conversaciones con la comunidad para determinar el significado cultural del arbol. Ademas de las publicaciones y referencias verbales, tambien se localizaron baobabs por medio de llamados al publico en entrevistas radiales y en periodicos. A pesar de que los usos de la flor del baobab aun estan pendientes de documentarse en forma comparable a las otras partes del arbol—especialmente el fruto, las hojas y la corteza—el presente estudio muestra que, contrario a lo que valoraciones prematuras sugieren, la flor esta lejos de ser de poca o ninguna utilidad. Este extracto inicial pretende atraer mas atencion a los usos de la flor en la investigacion del baobab, la cual es cada vez mas sofisticada y que ya se realiza en Africa y en otras latitudes.
Rapid Development of Infusion-Related Severe Hypotension During Rituximab Therapy

Objective To report an incident of rapid development of profound hypotension, differing from the time described in previous reports, during the infusion of rituximab chemotherapy in a patient without prior exposure to the drug. Case summary An 84-year-old white male with Rai stage IV chronic lymphocytic leukemia was prescribed rituximab 375 mg/m(2) by intravenous infusion. Rituximab 50 mg/h was initiated after premedication with acetaminophen, diphenhydramine, dexamethasone, and ondansetron 3 days into his hospital course. Five minutes after the infusion had begun, he experienced a significant decrease in blood pressure to 76/45 mm Hg, and the infusion was stopped. After 30 minutes, the blood pressure returned to normal. Rechallenge with rituximab 25 mg/h was attempted, but the blood pressure again declined and the patient experienced chills and rigors. The infusion was discontinued, and the symptoms resolved 1 hour later. Discussion Infusion-related adverse reactions associated with rituximab are reported at a higher rate than with other monoclonal antibodies. Hypotension with rituximab has been reported to occur 30 minutes to 2 hours after initiation of the infusion. In contrast, severe hypotension in our patient occurred within 5 minutes after the infusion was started in a patient with no previous exposure to the drug. While many studies hypothesize that cytokine release from lymphocytes and tumor cell agglutination might contribute to severe infusion-related reactions with rituximab, the mechanism of action is not yet known. Use of the Naranjo probability scale indicated that the hypotension was probably associated with rituximab administration. Conclusions Awareness of the rapidity of this adverse effect in patients who have not received prior treatment with monoclonal antibodies is important during chemotherapy treatment.
INHIBITION OF CARBAMOYL PHOSPHATE SYNTHETASE-I BY DIETARY DEHYDROEPIANDROSTERONE

Dehydroepiandrosterone (DHEA), administered per os, serves to prevent or retard the development of a variety of genetic and induced disorders in mice and rats. This treatment also results in the development of hepatomegaly, a change of liver color from pink to mahogany, peroxisome proliferation in hepatocytes and alterations in hepatocyte mitochondria morphology and respiration. We used one- and two-dimensional polyacrylamide gel electrophoresis (PAGE) to identify changes in the relative levels of liver proteins produced by DHEA treatment of rodents. In mouse liver, there were apparent increases in the levels of 26 proteins and decreases in the levels of 7 proteins. Of the induced proteins the most prominent had Mr approximately 72 K; this protein was identified in a previous study as enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase. Another protein of Mr approximately 28 K, of unknown nature, also was induced markedly by DHEA treatment of mice and rats. A protein of Mr approximately 160 K, which was identified as carbamoyl phosphate synthetase-I (CPS-I), was decreased markedly by DHEA action. This enzyme, which comprises approx. 15-20% of mitochondrial matrix protein, is involved in the entry and rate-limiting step of the urea cycle. The specific activity of CPS-I also was significantly decreased by DHEA, but serum urea levels were normal. To determine whether steroids other than DHEA also induced similar changes, mice were treated with various steroids for 14 days and, thereafter, liver proteins were evaluated by SDS-PAGE: estradiol-17 beta and isoandrosterone induced both the approximately 72 and approximately 28 kDa proteins, testosterone and androsterone induced the 28 kDa protein only, but etiocholanolone, pregnenolone and progesterone were without effect. The findings of this study serve to demonstrate that: (i) hepatic protein levels are affected by DHEA treatment of mice and rats; (ii) liver CPS-I activity is decreased significantly by DHEA treatment, but serum urea levels remain within the normal range; and (iii) sex steroids and some of their precursors, when administered per os, also alter liver protein levels.
Diffusion Magnetic Resonance Imaging: An Imaging Treatment Response Biomarker to Chemoradiotherapy in a Mouse Model of Squamous Cell Cancer of the Head and Neck

For the treatment of squamous cell cancer of the head and neck (SCCHN), the assessment of treatment response is traditionally accomplished by volumetric measurements and has been suggested to be prognostic for an eventual response to treatment. An early evaluation response during the course of radiation therapy could provide an opportunity to tailor treatment to individual patients. Diffusion magnetic resonance imaging (MRI) allows for the quantification of tissue water diffusion values, thus treatment-induced loss of tumor cells will result in the increase in water mobility at the microscopic level, which can be detected as an increase in tumor diffusion values before any volumetric changes occur. We evaluated the use of diffusion MRI as an imaging biomarker of treatment response in an orthotopic mouse model of SCCHN. Mice with murine squamous cells expressing the yeast transgene cytosine deaminase were treated with 5-fluorocytosine (5FC), ionizing radiation, and combined therapy and were compared with control animals both during and after treatment for changes in tumor volumes, diffusion values, and survival. Radiation therapy had minimal effect on volumetric growth rate, diffusion, or survival. Although 5FC and combination treatment resulted in similar reductions in tumor volumes, the combination treatment elicited a much greater increase in tumor diffusion values, which correlated with improved survival. Thus, diffusion MRI as an imaging biomarker has a potential for early evaluation of the response to chemoradiation treatment in SCCHN.
Meta-analysis of breast feeding, vaginal delivery and maternal IV drug abuse as vertical transmission risk factors. 692

Meta-analysis of breast feeding, vaginal delivery and maternal IV drug abuse as vertical transmission risk factors. 692
On the Subfamily Astatinae. Part Vi. the American Species in the Genus Dryudella Spinola (Hymenoptera: Sphecidae)

Ten American species of Dryudella are recognized and keyed; all are also described and discussed, and their relationships are evaluated. The biology of the genus is summarized and new information on nesting habits and new prey records are presented for D. rhimpa , n. sp., D. picta (Kohl); D. montana (Cresson); and D. pernix , n. sp. New synonymy includes D. florissantensis (Rohwer) placed under D. montana (Cresson), and D. aspera (Fox), D. kohlii (Cameron), and D. asperiformis (Rohwer) placed under D. picta (Kohl).
“Like Very Honest and Substantial Citizens”: Cony‐Catching as Social Performance

AbstractThis essay maps out the ways in which the figure of the cony‐catcher, as imagined in the pamphlets of Robert Greene and Thomas Dekker, puts forward a performative notion of social position. Unlike the prototypical vagrants of many rogue‐pamphlets who are seen as using disguise to dissimulate the “deserving poor,” the cony‐catcher's performance is designed to win the confidence of his social betters. It goes beyond mere physical disguise and encompasses the networks of manners, speech, tacit codes and conventions, and relations of kinship and property that construct the field of “class.” Their performance challenges traditional notions of identity and hierarchy even as it echoes the “courtesy literature” of the period which advices the growing number of the “middling sort” of people on all aspects of social conduct. Thus, while recent scholarship has explored the criminalization of vagrants, I argue that the discourse of crime responds to a wider sphere of perceived social transformation and crisis...
Development of bestatin-based activity-based probes for metallo-aminopeptidases.

A novel set of activity-based probes (ABPs) for functionally profiling metallo-aminopeptidases was synthesized based on the bestatin inhibitor scaffold, the first synthesis of bestatin analogues using solid-phase techniques. These ABPs were shown to label metallo-aminopeptidases, using both a biotin and a fluorophore reporter, in an activity-dependent manner. This probe class was also shown to be amenable to ‘click’ chemistry labeling for possible use in live cells. Finally, we demonstrate that the ABPs are able to label an aminopeptidase in a complex proteome. Thus, these bestatin-based probes should have wide utility to functionally profile aminopeptidases in many biological systems.
Wideband measurement of the magnetic susceptibility of soils and the magnetic polarizability of metallic objects

Broadband electromagnetic induction (EMI) sensors have been shown to be able to reduce false alarm rates and increase the probability of detecting landmines. To aid in the development of these sensors and associated detection algorithms, a testing facility and inversion technique have been developed to measure the magnetic response of soils and the magnetic polarizability of metal targets. When theoretical predictions are possible, these measurements show good agreement with theory.
How the tobacco industry continues to keep the home fires burning

On Friday, 24 September 1993, I kept a telephone appointment with Jeffrey Wigand that had been set up by a mutual colleague. This was our first of dozens of telephone conversations (to this day, I have not met Jeff in person) and I took notes of our talk. Jeff was reaching out to me to see if I could assist him in “whistleblowing” on his former employer, Brown & Williamson (B&W). I was committed to helping him—although I must admit I suspected that he was an industry spy, even as he claimed that he was the former director of research and development at B&W. I knew that this made Jeff the highest level whistleblower in the history of the tobacco industry. While still employed by B&W, Jeff had sat in the audience at public meetings of the Technical Advisory Group (TAG) on Fire Safe Cigarettes in Washington, DC, United States, and I was one of the 15 congressionally appointed members representing the American Burn Association and the American Public Health Association. After observing me at the meetings, Jeff felt that I would be sympathetic to his cause. Jeff asked if I could introduce him to members of Congress so that he could be “forced” to testify. All of this was in order for Jeff to tell the world what he knew about the corporate practices of B&W. And the corporate practice that I was most interested in was whether or not B&W was developing or had developed a fire-safe cigarette—or as defined by the National Institute of Standards and Technology (NIST), a cigarette with a “reduced propensity for igniting upholstered furniture and mattress fires”. This was the first question I put to Jeff that Friday afternoon. His answer was not surprising. He told me that all the cigarette companies had …
Ion Beam Milling of Fused Silica for Window Fabrication

Ion beam figuring has been demonstrated to be a deterministic efficient flexible technique for removing material from optical surfaces. Recent interest in using this process to produce high quality optical components has driven the need to fully characterize the resulting surfaces. We have performed a polishing parameter matrix investigation to optimize fused silica (Corning 7957) surfaces for subsequent ion milling. Samples were characterized for surface scatter surface absorption surface roughness subsurface damage and laser damage as a function of mill depth. Small defects (pits) were evident on surfaces after milling a few microns with pit density dependent to some degree upon the surface preparation technique. The defects were often in lines apparently following a surface or subsurface scratch in the materiaL Surface scatter decreased significantly (up to lOX) and laser damage threshold increased in some cases by 400. Laser damage was not correlated with defects in the material. Key words: ion beam milling laser damage scatter fused silica absorption. 1.
Ontology for Developing Web Sites for Natural Disaster Management: Methodology and Implementation

Recent natural disasters have highlighted the need for disaster preparedness, planning, and management. Hurricane Katrina demonstrated the usefulness of Web sites in dealing with natural disasters. However, little is known about the necessary contents and structures of Web-based information systems for natural disaster management. In this paper, we focus on developing an ontology structure of elements for Web-based disaster management systems. Web elements are identified, following a grounded-theory approach, from an inventory of 6032 Web pages drawn from 100 disaster management Web sites. Selected semi-structured data representation approaches are used to organize the resulting ontology structure, which consists of 2094 Web elements. The ontology structure is further coded into a Web-based system, allowing easy online access.
A comparison of men's and women's strength to body mass ratio and varus/valgus knee angle during jump landings

The purpose of this investigation was to compare valgus/varus knee angles during various jumps and lower body strength between males and females relative to body mass. Seventeen recreationally active females (age: 21.94 ± 2.59 years; height: 1.67 ± 0.05 m; mass: 64.42 ± 8.39 kg; percent body fat: 26.89 ± 6.26%; squat one-repetition maximum: 66.18 ± 19.47 kg; squat to body mass ratio: 1.03 ± 0.28) and 13 recreationally active males (age: 21.69 ± 1.65 years; height: 1.77 ± 0.07 m; mass: 72.39 ± 9.23 kg; percent body fat: 13.15 ± 5.18%; squat one-repetition maximum: 115.77 ± 30.40 kg; squat to body mass ratio: 1.59 ± 0.31) performed a one-repetition maximum in the squat and three of each of the following jumps: countermovement jump, 30 cm drop jump, 45 cm drop jump, and 60 cm drop jump. Knee angles were analysed using videography and body composition was analysed by dual-energy X-ray absorptiometry to allow for squat to body mass ratio and squat to fat free mass ratio to be calculated. Significant differences (P ≤ 0.05) were found between male and female one-repetition maximum, male and female squat to body mass ratio, and male and female squat to fat free mass ratio. Significant differences were found between male and female varus/valgus knee positions during maximum flexion of the right and left leg in the countermovement jump, drop jump from 30 cm, drop jump from 45 cm, and drop jump from 60 cm. Correlations between varus/valgus knee angles and squat to body mass ratio for all jumps displayed moderate, non-significant relationships (countermovement jump: r = 0.445; drop jump from 30 cm: r = 0.448; drop jump from 45 cm: r = 0.449; drop jump from 60 cm: r = 0.439). In conclusion, males and females have significantly different lower body strength and varus/valgus knee position when landing from jumps.
Role of domain swapping in the hetero-oligomeric cytochrome b6f lipoprotein complex.

Domain swapping that contributes to the stability of biologically crucial multisubunit complexes has been implicated in protein oligomerization. In the case of membrane protein assemblies, domain swapping of the iron–sulfur protein (ISP) subunit occurs in the hetero-oligomeric cytochrome b6f and bc1 complexes, which are organized as symmetric dimers that generate the transmembrane proton electrochemical gradient utilized for ATP synthesis. In these complexes, the ISP C-terminal predominantly β-sheet extrinsic domain containing the redox-active [2Fe-2S] cluster resides on the electrochemically positive side of each monomer in the dimeric complex. This domain is bound to the membrane sector of the complex through an N-terminal transmembrane α-helix that is “swapped’ to the other monomer of the complex where it spans the complex and the membrane. Detailed analysis of the function and structure of the b6f complex isolated from the cyanobacterium Fremyella diplosiphon SF33 shows that the domain-swapped ISP str...
Suppressors of Escherichia coli mutT: antimutators for DNA replication errors.

Previous studies in our laboratory used a papillation assay to identify a set of mutations in the E. coli dnaE gene that confer increased accuracy of DNA replication (antimutators). These antimutators were isolated as suppressors of the high mutability of a mismatch-repair-defective mutL strain, in which the majority of mutations represent uncorrected replication errors (mainly A · T → G · C and G · C → A · T transitions). In the present study, we have sought suppressors of the high mutability of a mutT mutator strain. mutT strains produce a high frequency of A · T → C · G transversions due to their lack of the mutT-encoded 8-oxo-dGTPase, leading to a high frequency of A · (8-oxoG) mispairing errors. Following localized mutagenesis of the dnaE-dnaQ region of the chromosome, two strong suppressors of mutT mutability were obtained, both residing in the dnaE gene (dnaE940 and dnaE941). When subsequently tested in a mutL strain, these two alleles also proved antimutators in this background, dnaE941 being significantly stronger than the previously isolated antimutators. The results suggest that the DNA polymerase may use similar mechanisms to discriminate against A · (8-oxoG) transversion mispairs and A · C or T · G transition mispairs. The findings may also have significance for the interpretation of the antimutator effect conferred by these dnaE alleles in a wild-type (mut+) background.
Path prediction for high issue-rate processors

Rapid developments in the exploitation of instruction-level parallelism are prompting deeper-pipelined, wider machines with high issue rates. Speculative execution has been used to provide the required issue bandwidth. Current methods predict a single branch at a time. Performance improvement is possible by predicting multiple branches in a single cycle. The paper presents a technique to predict paths in a single access. The correlation of a path with the branches executed before it, is exploited to provide high prediction accuracy. A novel path prediction automaton is presented The automaton is easily scalable to predict long paths through arbitrary subgraphs. It also predicts a path through a subgraph in a single access. The automaton requires only n+1 bits for predicting the 2/sup n/ paths in a subgraph of depth n. The performance of the proposed path predictor is measured. The full path accuracy (accuracy in predicting all the branches in a path) is higher than or equal to other predictors found in the literature. This performance is achieved at a low hardware cost. The scalability single access prediction and low hardware cost of the path prediction technique presented in the paper make it suitable for machines requiring high issue bandwidth.
An α-Formylglycine Building Block For Fmoc-Based Solid-Phase Peptide Synthesis

Nearly all known sulfatases share a common active site modification that is required for their activity: conversion of cysteine to α-formylglycine. We report the synthesis of an α-formylglycine building block suitable for Fmoc-based solid-phase peptide synthesis. The building block was incorporated into a synthetic peptide derived from the active site of a Mycobacterium tuberculosis sulfatase.
Seismic Response Analysis of a Highway Overcrossing Equipped with Elastomeric Bearings and Fluid Dampers

This paper presents a case study on the seismic response of a recently constructed freeway overcrossing located in southern California, which is equipped with elastomeric bearings and fluid dampers at its end abutments. The analysis employs the substructure method and a reduced order stick model. The macroscopic constitutive laws of the springs and dashpots that approximate the mechanical behavior of approach embankments, pile foundations, center bent, abutments, elastomeric bearings, and fluid dampers are established in the companion paper. The paper presents an in-depth analysis of the seismic response of the bridge equipped with the response modification devices accounting for the effects of soil–structure interaction. The various response quantities presented are compared with the corresponding response quantities of a hypothetical bridge with integral abutments. Advantages and challenges in the two design configurations are identified and discussed.
Degradation of Polychlorinated Biphenyls Induced by Ionizing Radiation in Aqueous Micellar Solutions

This investigation examines the γ-radiation-induced degradation of polychlorinated biphenyls (PCBs) in aqueous surfactant solutions. Dichloro-, tetrachloro-, and decachlorobiphenyl congeners were solubilized in water using a commercially available non-ionic surfactant, Triton X-100, and subsequently irradiated by a 60Co γ-source. Rates and extent of dechlorination were determined at different surfactant concentrations, and intermediate species and byproducts were quantified. Pulse radiolysis was used to measure rates of reaction between PCBs and the solvated electron as well as rates of electron scavenging by the surfactant. Experiments were also conducted in organic solvents, and these results have been compared to those observed in the aqueous surfactant solutions. Each PCB congener was fully dechlorinated by ionizing radiation in the micellar systems. Initial chloride yields were directly proportional to the level of chlorination of the PCB congeners. Scavenging of the aqueous electron by the surfactan...
William H. Beezley and David E. Lorey (eds), ¡Viva Mexico! ¡Viva la independencia!: Celebrations of September 16, Wilmington, SR Books, 2001.

Abstract This book is a welcome addition to the study of public commemorations in Latin America. All but one chapter stick closely to a very specific commemoration, Mexico's annual celebration of Independence from Spain. Chapters are organised chronologically, beginning with the initial struggles for independence in the decade after 1810 and ending roughly in the late 1940s. The book is a transnational effort, with five contributions written in English and five translated from the Spanish. Three have been previously published in U.S. or Mexican journals.
A kinetic and thermochemical database for organic sulfur and oxygen compounds

Potential energy surfaces and reaction kinetics were calculated for 40 reactions involving sulfur and oxygen. This includes 11 H2O addition, 8 H2S addition, 11 hydrogen abstraction, 7 beta scission, and 3 elementary tautomerization reactions, which are potentially relevant in the combustion and desulfurization of sulfur compounds found in various fuel sources. Geometry optimizations and frequencies were calculated for reactants and transition states using B3LYP/CBSB7, and potential energies were calculated using CBS-QB3 and CCSD(T)-F12a/VTZ-F12. Rate coefficients were calculated using conventional transition state theory, with corrections for internal rotations and tunneling. Additionally, thermochemical parameters were calculated for each of the compounds involved in these reactions. With few exceptions, rate parameters calculated using the two potential energy methods agreed reasonably, with calculated activation energies differing by less than 5 kJ mol−1. The computed rate coefficients and thermochemical parameters are expected to be useful for kinetic modeling.
805A PROGNOSIS AFTER 3-YEAR SURVIVAL IN CHILDHOOD ACUTE LYMPHOBLASTIC LEUKEMIA (ALL)

The appropriate duration of therapy for childhood ALL remains controversial. 82 children(M:F, 47:35) with ALL were diagnosed between 1965-1975. Forty (49%)children, including 18 males,remained in complete continuous remission (CCR) at 3 years. Between the third and fifth years of therapy, 3 males and 3 females relapsed. The sites of initial relapse were the CNS in 5(4 had received CNS prophylaxis) and a simultaneous marrow and testicular relapse in the sixth. Five were initially high risk patients by age( 8 years)or white count(≥30,000/mm3) criterian. One additional child died, in remission, of varicella complications. 33 patients (40%) remained in CCR at least 5 years. They had received chemotherapy for a median of 61 mos. Followup times off therapy ranged from 6-178 mos (median 36+ mos). One boy in this group subsequently relapsed in the marrow 16 months after therapy ended. We conclude that the relapse rate of 17.5% (7/40) after 3 years of CCR is comparable to the 20% relapse rate reported by St. Jude Children's Research Hospital (NEJM 300:269, 1979), although our patients received therapy for an additional 2+ years. Continuing therapy beyond 3 years would therefore seem to subject patients to continued potential morbidity without improving ultimate prognosis.
Mechanism for the T4 lymphopenia of AIDS Silvio Micali

Abstract I suggest that the T4 lymphopenia of AIDS may be caused by antibodies raised against the human immunodeficiency virus that block the generation of T4 cells.
A factor-analytic study of creative-thinking abilities.

Fifty-three tests designed to measure aspects of creative thinking were administered to 410 air cadets and student officers. The scores were intercorrelated and 16 factors were extracted. Orthogonal rotations resulted in 14 identifiable factors, a doublet, and a residual. Nine previously identified factors were:verbal comprehension, numerical facility, perceptual speed, visualization, general reasoning, word fluency, associational fluency, ideational fluency, and a factor combining Thurstone'sclosure I andII. Five new factors were identified asoriginality, redefinition, adaptive flexibility, spontaneous flexibility, andsensitivity to problems.
Site-specific Tyrosine Phosphorylation of IκBα Negatively Regulates Its Inducible Phosphorylation and Degradation

The transcription factor NF-κB is retained in the cytoplasm by its interaction with the inhibitory subunit known as IκB. Signal-induced serine phosphorylation and subsequent ubiquitination of IκBα target it for degradation by the 26 S proteasome. Recently, pervanadate, a protein-tyrosine phosphatase inhibitor, was shown to block the degradation of IκBα, thus inhibiting NF-κB activation. We investigated the mechanism by which pervanadate inhibits the degradation of IκBα. Western blot analysis of IκBα from tumor necrosis factor-treated cells revealed a slower migrating IκBα species that was subsequently degraded. However, pervanadate-treated cells also revealed a slower migrating species of IκBα that appeared in a time- and dose-dependent manner and was not degraded by tumor necrosis factor. The slower migrating species of IκBα from pervanadate-treated cells was tyrosine-phosphorylated as revealed by cross-reactivity with anti-phosphotyrosine antibodies, by the ability of the specific tyrosine phosphatase PTP1B to dephosphorylate it, and by phosphoamino acid analysis of IκBα immunoprecipitated from 32P-labeled cells. By site-specific mutagenesis and deletion analysis, we identified Tyr-42 on IκBα as the phosphoacceptor site. Furthermore, in an in vitro reconstitution system, tyrosine-phosphorylated IκBα was protected from degradation. Our results demonstrate that inducible phosphorylation and degradation of IκBα are negatively regulated by phosphorylation at Tyr-42, thus preventing NF-κB activation.
On the correlation of configurational changes in the inner mitochondrial membrane with energization.

Two reports in the literature that mitochondria isolated in special media or from a particular source do not undergo configurational changes under energizing, conditions have been analyzed in detail. It could be shown that the failure to demonstrate configurational changes was a consequence of a procedure which allowed anaerobiosis to set in before the mitochondria were fixed. When fixation was achieved while the mitochondria were still under energizing conditions, the correlation between configurational change and change in the energy state could be confirmed.
Annealing Behavior of the Hydrogen-Vacancy Complex in Bulk Indium Phosphide Crystals

In order to explain the effects of hydrogen on the electrical properties of bulk indium phosphide crystals, they have performed a series of high temperature annealing studies with both undoped and iron-doped indium phosphide crystals. The samples were annealed at 900 C for 6, 36, and 72 hours, respectively, under a phosphorus overpressure of five atmospheres. Samples were characterized at 10 K by Fourier transform infrared absorption spectroscopy which allowed us to measure the concentrations of both the Fe{sup 2+} and V{sub In}-H{sub 4} defects simultaneously. Undoped samples were further characterized by the Hall effect measurements. The authors find in the iron-doped samples that the [Fe{sup 2+}]/[Fe{sup 3+}] ratio decreases gradually with increasing annealing time, indicating a reduction in the number of donors in the samples. In the undoped samples, annealing leads to a reduction of the free electron concentration accompanied by an increase in the 77 K mobility. The increase of the sample`s mobility eliminates the possibility that the reduction of the free electron concentration is due to an increase in the concentration of the compensating acceptors. The explanation for the observed behavior in all samples is that hydrogen acts as a donor and it diffuses out of themore » crystal during the annealing process. Based on the experimental data, they propose a calibration equation of [V{sub In}-H{sub 4}] = 4.2 {times} 10{sup 16} cm{sup {minus}1} {times} Absorbance (cm{sup {minus}1}) which is used to correlate the hydrogen-vacancy complex concentrations with the changes of the V{sub In}-H{sub 4} absorption peak in both the iron-doped and the undoped samples. Their results confirm the donor nature of the hydrogen-vacancy complex and provide strong evidence regarding the reduction mechanism of free carrier concentrations in bulk indium phosphide crystals during high temperature annealing under a phosphorus atmosphere.« less
Fluorescence and phosphorescence of 5- and 8-aminoquinoline

Abstract 5-Aminoquinoline and 8-aminoquinoline fluoresce moderately to weakly in low dielectric media but not in strongly hydrogen-bonding or acidic aqueous media. At low temperatures and in rigid media moderately intense fluorescence is observed in aqueous, media at all pH values. Quenching of the aminoquinoline fluorescences in fluid media is believed to be due primarily to hydrogen bonding in the lowest excited singlet state. The fluorescences of the aminoquinolines arise from the 1La states in the respective molecules. Calculation of approximate excited singlet state pKa* values indicates that upon excitation to the 1La state the amino group becomes a weaker base while the heterocyclic ring nitrogen becomes a stronger base. Phosphorescence is observed for the doubly protonated cations of both aminoquinolines but not for the singly protonated or neutral species. Both neutral species exhibit delayed fluorescence at 77° K.
A high accuracy sequential solver for simulation and active control of a longitudinal combustion instability

A high accuracy convection scheme using a sequential solution technique has been developed and applied to simulate the longitudinal combustion instability and its active control. The scheme has been devised in the spirit of the Total Variation Diminishing (TVD) concept with special source term treatment. Due to the substantial heat release effect, a clear delineation of the key elements employed by the scheme, i.e., the adjustable damping factor and the source term treatment has been made. By comparing with the first-order upwind scheme previously utilized, the present results exhibit less damping and are free from spurious oscillations, offering improved quantitative accuracy while confirming the spectral analysis reported earlier. A simple feedback type of active control has been found to be capable of enhancing or attenuating the magnitude of the combustion instability.
Water Aided Fabrication of Whey and Albumin Plastics

Development of polymeric materials that can reduce the reliance on petroleum derived synthetic polymers involves biopolymers such as proteins, starch, cellulose and lipids which can be obtained as agricultural co-products or by-products. Specifically, bioplastics from protein feedstock may have significant advantages over traditional plastics, especially in areas such as packaging, agriculture, horticulture and medical materials. This article focuses on fabricating plastics from whey and albumin proteins and describing properties of plastics made from them. These protein biomasses were plasticized using water and compression molded into plastic samples. Results indicated the importance of water on plasticization during fabrication and on mechanical performance later due to densification during drying.
The efficacy of sildenafil citrate (Viagra®) in clinical populations: an update

Although certain risk factors are known to be associated with erectile dysfunction (ED), the demographic and ED characteristics of the population of men with ED are quite diverse. We examined results from randomized trials of sildenafil citrate (Viagra) to ascertain if efficacy differed across various subgroups of men with ED. In addition, we reviewed findings from long-term extension studies and published accounts of sildenafil use in clinical practice to determine if effectiveness is maintained with long-term sildenafil treatment and to determine if effectiveness in the clinic practice setting is consistent with that reported in clinical trials. Data were pooled from 11 double-blind, placebo-controlled, flexible-dose (taken as needed) studies to assess efficacy (N = 2667) of sildenafil in men (aged 23 to 89 years) with ED of broad-spectrum etiology who were not receiving concomitant nitrate therapy. Efficacy evaluations included the International Index of Erectile Function, a global efficacy question ("Did treatment improve your erections?"), and a patient-recorded event log of sexual activity. Significantly improved erectile function was demonstrated for sildenafil compared with placebo for all efficacy parameters analyzed (P 95% of patients reported that they were satisfied with the effect of treatment on their erections, and that treatment had improved their ability to engage in sexual activity. Findings from published accounts of sildenafil use in the clinical practice setting further demonstrated that sildenafil is an effective treatment for a wide range of patients with ED.
WE-A-T-6C-01: The Physics of HDR Breast Brachytherapy

Purpose: To discuss physical considerations of breast brachytherapy. Method and Materials: Breast brachytherapy is rapidly becoming a common procedure, driven, to a great extent, by patient demand. Most therapy regimens deliver the definitive course over four or five days of B.I.D. treatments. The treatments irradiate the target at risk without unnecessary exposure to skin (except as noted below) or lung. The placement of catheters is performed with a minimum of pain, and the patients tolerate well the presence of catheters over the week duration. Currently, there are two approaches to breast brachytherapy. One major approach places the patient prone on a breast biopsy table with the target breast hanging through a hole in the table. Using a digital mammography unit, the radiation oncologist places a needle-guiding template on the breast. Holes in the template are selected that cover the tylecomy cavity plus a 2 cm margin (the clinical target volume, CTV). Another approach begins with the patient supine, and uses either ultrasound or CT guidance for needle placement. With any of the approaches, flexible catheters replace the needles, and CT images are taken for dosimetry planning. Optimization molds the prescription isodose surface to the CTV, with no coalescing of the 150 percent isodose surface around more than single catheters. The other approach uses a single balloon catheter placed in the tylectomy cavity, either at the time of surgery or shortly thereafter. While easier for both the patient and the physician, placing the catheter at the time of surgery runs the risk of having to remove it if pathological examination shows insufficient margins around the tumor. The balloon is then filled with saline and dilute contrast medium to fill the cavity. The dose is prescribed to an isodose surface 1 cm beyond the balloon surface. For spherical balloons, often a single dwell position is placed in the center of the balloon, although some facilities add short dwells along the catheter to compensate for source anisotropy. Oblong balloons always require multiple dwell positions. The intracavitary approach often produces higher skin doses than the interstitial, and finding a skin dose greater than 150% is reason to abort the treatment. Air cavities often become trapped near the surface of the balloon, pushing the target tissue outside the treatment levels of dose. While the air pockets sometimes disappear with time, they often simply fill with fluid, leaving the target tissue at a great distance. Only MRI can determine if the tissue has collapsed onto the balloon or the pocket filled with fluid. Air pockets of 1 mm and 1.6 mm reduce the dose to target tissue by 5% and 10% respectively. For either approach, quality management plays an important role, and prevents inappropriate treatments. Results: Comparing the two, the intracavitary approach is slightly simpler but more prone to aborting the procedure, while the interstitial approach allows high conformance of the isodose distribution to the CTV. Conclusion: Breast brachytherapy provides an effect delivery vehicle for patient breast radiotherapy.