cssi/SciSciGPT-SciSciNet huggingface dataset:
Multi-Omic Analyses Provide Links between Low-Dose Antibiotic Treatment and Induction of Secondary Metabolism in Burkholderia thailandensis

Low doses of antibiotics can trigger secondary metabolite biosynthesis in bacteria, but the underlying mechanisms are generally unknown. We sought to better understand this phenomenon by studying how the antibiotic trimethoprim activates the synthesis of the virulence factor malleilactone in Burkholderia thailandensis Using transcriptomics, quantitative multiplexed proteomics, and primary metabolomics, we systematically mapped the changes induced by trimethoprim. Surprisingly, even subinhibitory doses of the antibiotic resulted in broad transcriptional and translational alterations, with ∼8.5% of the transcriptome and ∼5% of the proteome up- or downregulated >4-fold. Follow-up studies with genetic-biochemical experiments showed that the induction of malleilactone synthesis can be sufficiently explained by the accumulation of methionine biosynthetic precursors, notably homoserine, as a result of inhibition of the folate pathway. Homoserine activated the malleilactone gene cluster via the transcriptional regulator MalR and gave rise to a secondary metabolome which was very similar to that generated by trimethoprim. Our work highlights the expansive changes that low-dose trimethoprim induces on bacterial physiology and provides insights into its stimulatory effect on secondary metabolism.IMPORTANCE The discovery of antibiotics ranks among the most significant accomplishments of the last century. Although the targets of nearly all clinical antibiotics are known, our understanding regarding their natural functions and the effects of subinhibitory concentrations is in its infancy. Stimulatory rather than inhibitory functions have been attributed to low-dose antibiotics. Among these, we previously found that antibiotics activate silent biosynthetic genes and thereby enhance the metabolic output of bacteria. The regulatory circuits underlying this phenomenon are unknown. We take a first step toward elucidating these circuits and show that low doses of trimethoprim (Tmp) have cell-wide effects on the saprophyte Burkholderia thailandensis Most importantly, inhibition of one-carbon metabolic processes by Tmp leads to an accumulation of homoserine, which induces the production of an otherwise silent cytotoxin via a LuxR-type transcriptional regulator. These results provide a starting point for uncovering the molecular basis of the hormetic effects of antibiotics.
A New Computational Technique Design for EMHD Nanofluid Flow Over a Variable Thickness Surface With Variable Liquid Characteristics

The objective of paper comprises two key points: descriptive mathematical model for constant and variable fluid flows over a variable thickness sheet by inducting applied electric and magnetic fields, porosity, radiative heat transfer, heat generation/absorption and seeking their solution by constructing a novel numerical method, the Simplified Finite Difference Method (SFDM). We resort to similarity transformations to implicate partial differential equations (PDEs) into a set of ordinary differential equations (ODEs). Optimal results for a pair of ODEs obtained from SFDM are assessed by drawing a comparison with \emph{bvp4c} and existing literature values. SFDM has been implemented in MATLAB for both constant and variable fluid properties. Tabulated numerical values of the skin friction coefficient, local Nusselt and Sherwood numbers are measured and analyzed against different parameters. Influence of distinct parameters on velocity, temperature, and nanoparticles volume fraction have been explained in great detail via diagrams. The skin friction coefficient for variable fluid properties is greater than the constant fluid properties. However, the local Nusselt number is less for variable fluid properties when compare with constant fluid properties. Surprisingly, the high precision computational results are achieved from the SFDM.
Indigenous Science for a World in Crisis

A growing body of work illustrates that community-based archaeology can contribute in valuable and meaningful ways to communities, including helping individuals and groups to heal from historical t...
Monster, P.I.: Validation Evidence for an Assessment of Adolescent Language That Assesses Vocabulary Knowledge, Morphological Knowledge, and Syntactical Awareness:

Assessment of language skills for upper elementary and middle schoolers is important due to the strong link between language and reading comprehension. Yet, currently few practical, reliable, valid...
Interleukin-17A Facilitates Chikungunya Virus Infection by Inhibiting IFN-α2 Expression.

Interferons (IFNs) are the key components of innate immunity and are crucial for host defense against viral infections. Here, we report a novel role of interleukin-17A (IL-17A) in inhibiting IFN-α2 expression thus promoting chikungunya virus (CHIKV) infection. CHIKV infected IL-17A deficient (Il17a-/- ) mice expressed a higher level of IFN-α2 and developed diminished viremia and milder footpad swelling in comparison to wild-type (WT) control mice, which was also recapitulated in IL-17A receptor-deficient (Il17ra-/- ) mice. Interestingly, IL-17A selectively blocked IFN-α2 production during CHIKV, but not West Nile virus (WNV) or Zika virus (ZIKV), infections. Recombinant IL-17A treatment inhibited CHIKV-induced IFN-α2 expression and enhanced CHIKV replication in both human and mouse cells. We further found that IL-17A inhibited IFN-α2 production by modulating the expression of Interferon Regulatory Factor-5 (IRF-5), IRF-7, IFN-stimulated gene 49 (ISG-49), and Mx1 expression during CHIKV infection. Neutralization of IL-17A in vitro leads to the increase of the expression of these antiviral molecules and decrease of CHIKV replication. Collectively, these results suggest a novel function of IL-17A in inhibiting IFN-α2-mediated antiviral responses during CHIKV infection, which may have broad implications in viral infections and other inflammatory diseases.
Searching to avoid regret: An experimental evidence

Abstract When faced with many options, individuals generally gather information prior to choosing. In this study, I identify the role of post-decision feedback on quality of missed alternatives, which can induce regret in decision-making, to explain the extent to which people would search. I isolate the effect of feedback on search levels cleanly by means of an abstract lab experiment set in a sequential search environment. The feedback levels vary across treatments. I find that individuals not only have higher reservation values that lead them to sample more options in the presence of this regret-inducing feedback, but their reservation values also decline less slowly over time in the presence of said feedback. Thus, the presence of feedback on forgone alternatives induces decision-makers to exhibit higher search intensities, indicating the important role played by regret aversion in search environments.
An Exploratory Examination of Student-Led, Asynchronous Collaborative Online Discussions in Fostering Higher-Order Cognitive Skills and Ethical Leadership Learning

Previous studies have contextualized student-led, asynchronous online discussions as collaborative learning experiences that positively impact students’ learning and foster higher order cognitive skills. From a leadership education perspective, student-led discussions have come to the fore as a helpful resource for deepening learning because of their focus on collaboration and shared leadership. While literature on student-led online discussions, leadership learning, and cognitive skill is plentiful, there is no single study that explores all these elements together or fully points to how practicing meaning-making in online, asynchronous leadership courses can inform larger cognitive processes. Thus, the purpose of this conceptual content analysis-based study was to examine 35 undergraduate students’ collaborative discussion board posts at the beginning, middle, and end of an online, asynchronous Ethics and Leadership class to assess not only if and to what extent students expressed cognitive skills, in general, but also if and to what extent they understood ethical leadership via these types of discussions. Further, from an exploratory lens, this study examined if there was a relationship between expression of higher order cognitive skills and more complex ethical leadership understanding. Results indicate that, while students achieved higher order cognitive skills and more holistic ethical leadership understanding overall, robustness of student engagement could be situational in nature and expressions of cognitive skills and ethical leadership understanding tapered as the course progressed. Additional findings and implications are discussed.
Augmented eccentrics: acute effects on jump performance

iv Acknowledgements v List of Tables ix List of Figures x List of Appendices xi CHAPTER I THE PROBLEM AND ITS SCOPE Introduction 1 Purpose of the study 3 Experimental Hypothesis 4 Significance of the Study 4 Limitations 4 Definition of Terms 5 CHAPTER II REVIEW OF LITERATURE Introduction 9 Residual Force Enhancement 10
Comparisons of Vibrated Density and Standard Compaction Tests on Sands with Varying Amounts of Fines

THE EFFECTS OF GRADATION,PERCENTAGE AND PLASTICITY OF FINES, AND MOISTURE ON VIBRATORY AND IMPACT COMPACTION OF GRANULAR SOILS WERE INVESTIGATED BY ADDING MEASURED PERCENTAGES OF LOW PLASTICITY (ML) AND MEDIUM PLASTICITY (CL) FINES TO A POORLY GRADED (SP) AND NEARLY WELL GRADED (SW-SP) SAND. RESULTS INDICATED THAT MORE FINES CAN BE ADDED TO A UNIFORM SAND AND THAT A UNIFORM SAND DENSIFIES BY VIBRATION MORE EFFECTIVELY THAN A WELL GRADED SAND. THE SAME DENSITIES ARE PRODUCED BY IMPACT AND VIBRATORY COMPACTION AT HIGHER PERCENTAGE OF FINES ADDED TO THE WELL GRADED SAND COMPARED TO THE PERCENT FINES ADDED TO THE UNIFORM SAND.MOISTURE AND PLASTICITY ARE INTERRELATED FACTORS WHICH GREATLY AFFECT COMPACTION.SATURATION FACILITATED VIBRATORY COMPACTION OF LOW PLASTICITY MIXTURES;HOWEVER,FOR MORE PLASTIC MIXTURES, ADHESION OF THE FINES TO THE SAND GRAINS RESTRICTED VIBRATORY DENSIFICATION. CURRENT COMPACTION TEST SELECTION CRITERIA,WHICH IGNORE PLASTICITY AND MOISTURE EFFECTS BY COMPARING VIBRATORY DENSITIES OF OVEN-DRY MATERIALS WITH THOSE DETERMINED BY STANDARD COMPACTION,CAN LEAD TO THE UNTENABLE CONCLUSION THAT VIBRATORY COMPACTION SHOULD BE USED FOR SANDS CONTAINING IN EXCESS OF 20 PERCENT FINES. /AUTHOR/
Topological Characterizations of Spaces

Publisher Summary Despite over a century of attention, there are surprisingly few topological spaces that can be given succinct elementary characterizations in purely topological terms. This chapter lists some of the more prominent spaces, restricted to the separable metric spaces, which are characterized by Urysohn's Metrization Theorem as the regular Hausdorff spaces satisfying the second axiom of countability. It begins with the simplest and most widely applied Cantor's middle third set which states that a non-void topological space X is homeomorphic with the Cantor set C provided that it is compact, metrizable, zero-dimensional, and perfect. It then reviews other subsets of the real line. If X is a connected topological space, a subset S ⊂ X separates X provided that X-S is equal to A⋃B, where A and B are open, disjoint, and non-empty. X is non-degenerate provided that it has more than one point. A component of a space is a maximal connected set. A space homeomorphic with the closed interval is frequently called an arc; if the end points, the ones that do not separate the arc, are deleted, the result, homeomorphic with the real numbers, is often termed an open arc.
Experimentation in an Academic Library: A Study in Security and Individual Student Engagement

The Special Collections and Rare Book Department at Western Michigan University collaborated with a student worker to develop a system to improve security and employee performance. The student was taking a course in psychology that required him to develop a workplace behavioral intervention with a client and modify an important behavior for employee performance. The article explains both the timer system developed to remind student workers to monitor users and discusses the benefits to the student and the department in working with the curriculum. The project employed techniques of behavioral psychology. It increased attentiveness to patrons and improved monitoring of item handling. The project illustrated the role libraries can play in student instruction through non-traditional approaches to internships and practical experience.
A taxonomy of customer relationship management analyses for data warehousing

Customer Relationship Management (CRM) is a strategy that supports an organization's decision-making process to retain long-term and profitable relationships with its customers. Effective CRM analyses require a detailed data warehouse model that can support various CRM analyses and deep understanding on CRM-related business questions. In this paper, we present a taxonomy of CRM analysis categories. Our CRM taxonomy includes CRM strategies, CRM category analyses, CRM business questions, their potential uses, and key performance indicators (KPIs) for those analysis types. Our CRM taxonomy can be used in selecting and evaluating a data schema for CRM analyses, CRM vendors, CRM strategies, and KPIs.
Bounded Ciphertext Policy Attribute Based Encryption

In a ciphertext policy attribute based encryption system, a user's private key is associated with a set of attributes (describing the user) and an encrypted ciphertext will specify an access policy over attributes. A user will be able to decrypt if and only if his attributes satisfy the ciphertext's policy. In this work, we present the first construction of a ciphertext-policy attribute based encryption scheme having a security proof based on a number theoretic assumption and supporting advanced access structures. Previous CP-ABE systems could either support only very limited access structures or had a proof of security only in the generic group model. Our construction can support access structures which can be represented by a bounded size access tree with threshold gates as its nodes. The bound on the size of the access trees is chosen at the time of the system setup. Our security proof is based on the standard Decisional Bilinear Diffie-Hellman assumption.
Patent and Trademark Depository Libraries and the United States Patent and Trademark Office: A Model for Information Dissemination

This paper describes the network of Patent and Trademark Depository Libraries (PTDLs), a collaborative partnership with the United States Patent and Trademark Office (USPTO) for disseminating patent and trademark information in every state plus the District of Columbia and Puerto Rico. Typical information sources and services provided at PTDLs are given, followed by suggestions of areas on which to focus in the future for PTDLs to continue to be vital links of information that spur economic growth, business competitiveness, and the continued discovery of new scientific and technological knowledge and applications.
Liquid Hot Water Pretreatment of Cellulosic Biomass

Lignocellulosic biomass is an abundant and renewable resource for fuel ethanol production. However, the lignocellulose is recalcitrant to enzymatic hydrolysis because of its structural complexity. Controlled-pH liquid hot water (LHW) pretreatment of cellulosic feedstock improves its enzymatic digestibility by removing hemicellulose and making the cellulose more accessible to cellulase enzymes. The removed hemicellulose is solubilized in the liquid phase of the pretreated feedstock as oligosaccharides. Formation of monomeric sugars during the LHW pretreatment is minimal. The LHW pretreatment is carried out by cooking the feedstock in process water at temperatures between 160 and 190 degrees C and at a pH of 4-7. No additional chemicals are needed. This chapter presents the detailed procedure of the LHW pretreatment of lignocellulosic biomass.
A model for estimating the composition of partial melts

A model is presented for estimating the major element composition of almost any partial melt derived from natural silicate rocks, given that the source composition and physical conditions of melting are known. Another model allows the estimation of water solubility in silicate melts. These models are simple empirical equations based on a database of 1608 experimental results from the literature. The results can be used in the planning of future experimental work or for the interpretation of natural rocks when more accurate methods are not available.
On the Possibility of New Particle Production in Heavy-Ion Collisions

Experimental identification of narrow peaks in the positron spectra emitted in the low-energy collisions of heavy ions1-4 has brought many surprises. Such structures were predicted to be present when the collision leads to a long-lived nuclear complex.5 However, the observed Z-dependence of the peak energy and the cross section does not seem to be consistent with the hypothesis that quasimolecular nuclear configurations are formed. The 1s binding energy for those systems is expected to vary strongly with the total nuclear charge Z.6 Hence, when this binding energy exceeds twice the electron mass,7 the spontaneously created positron would have an energy strongly dependent on Z. Initial data1–3 indicated that there is at least one constant peak energy for all the systems investigated, supercritical or subcritical. More recent measurements8,9 seem to unveil the existence of a multiple structure in the positron emission spectra, again with little Z-dependence.
Cell biology of the asialoglycoprotein receptor system: a model of receptor-mediated endocytosis

Substantial information about the ASGP-R has accumulated in the 10 years following the initial studies of this receptor by Ashwell and Morell. Many of its biochemical properties, its structure, and its orientation within the plasma membrane are now known. The pathways of ASGP ligand and receptor, with the CURL organelle being a central component, are summarized in Fig. 18. The major pathway of the ligand through the cell, beginning with binding at the cell surface and ending with degradation in lysosomes, has been investigated in detail. Recently, alternate routes of the ligand such as the ligand recycling pathway have been observed. With regard to the itinerary of the receptor, there is now biochemical, kinetic, and morphological evidence to support receptor recycling. The new concept of CURL as an important intracellular organelle has originated from studies of ASGP-R recycling. Its importance in the dissociation and segregation of ligand and receptor as well as in receptor recycling is now evident. In addition, there has been a concurrent investigation of other receptor systems that participate in receptor-mediated endocytosis, providing parallels and contrasts to the ASGP-R of hepatocytes. Many critical issues still exist in the cell biology of the ASGP-R. What are the structural requirements of the receptor for ligand binding and subsequent endocytosis of the receptor-ligand complex? Very little is known about the interactions between the receptor and the lipid bilayer in which it resides. How does the receptor move laterally in the plasma membrane? Are there proteins or glycolipids closely associated with the ASGP-R and, if so, what is their function? What is the mechanism that causes receptor clustering into coated pits? Although the existence of a pathway for ligand recycling has been demonstrated, there are still many issues to be addressed. What signals a particular ligand molecule for recycling? Is it a stochastic process? What is the function of this route of ligand movement? How are the various ligand pathways coordinated and regulated? In addition, there are many unanswered questions regarding the receptor pathway. How does CURL mediate the sorting of ASGP-R from ligand? How are receptors with different destinations (e.g., ASGP-R and IgA receptor) sorted in CURL? What is the mechanism of ASGP-R degradation and how is it regulated? Finally, how does the Golgi function in the ASGP system and what is the relationship between the Golgi and CURL? Future investigation of these issues will require further observations with existing techniques as well as new approaches.(ABSTRACT TRUNCATED AT 400 WORDS)
Expression of Cryptic β-Fructofuranosidase in Saccharomyces rouxii

Abstract Raffinose hydrolysis was studied in Saccharomyces rouxii. The responsible enzyme was identified as a β-fructofuranosidase (EC 3.2.1.26), which has a pH optimum of 5.5 and a Km of 83 mM for raffinose. This enzyme was cryptic in cells from a 3-day culture. A 2-min treatment with 0.1 volume of ethyl acetate in sodium acetate buffer (pH 6) gave complete expression of the enzyme, which was still retained by the cell. Ghosts were prepared by modifying membrane structure with small basic proteins in distilled water, and after washing they showed the full complement of enzymatic activity. The enzyme remained cryptic in osmotically protected spheroplasts; however, after lysis (by dilution) release, as well as expression, was effected. Mechanical disruption of fresh cells revealed and released all of the enzyme. Cells in early stationary phase had all of their β-fructofuranosidase in a cryptic state. Aging yielded fractional expression of activity; initially this was proportional to cell death, but later the degree of expression exceeded the death rate. Media from aged cultures or cell-free extracts of aged cells were not effective in revealing the cryptic enzyme of younger cells. S. rouxii β-fructofuranosidase has a different autolytic-release pattern from its counterpart in S. cerevisiae. Also, high concentrations of glucose do not repress the S. rouxii enzyme. The β-fructofuranosidase in young cells of S. rouxii must be enclosed by the protoplasmic membrane or a special vesicular structure. This system was compared with other Saccharomyces species in connection with the translocation of enzymes across the protoplasmic membrane.
Caribbean Law: Traditions from Colonial History

Like the legal systems of Europe and the United States, legal systems in Caribbean nations are based either on civil law or common law or a mixture of both traditions. Given their similar colonial histories, many Caribbean nations have shared legal traditions. This is particularly evident in the former British colonies, and similar comparisons may be made among the Caribbean nations which share a civil law tradition. However, the legal systems of Caribbean civil law countries are less similar to one another as a result of the differences in the laws of the countries that colonized them, the relative paucity of fully autonomous civil law states in the Caribbean, and the unique political histories of Cuba, the Dominican Republic, and Haiti.
Defective motion processing in children with cerebral visual impairment due to periventricular white matter damage

Aim We sought to characterize visual motion processing in children with cerebral visual impairment (CVI) due to periventricular white matter damage caused by either hydrocephalus (eight individuals) or periventricular leukomalacia (PVL) associated with prematurity (11 individuals). Method Using steady-state visually evoked potentials (ssVEP), we measured cortical activity related to motion processing for two distinct types of visual stimuli: ‘local’ motion patterns thought to activate mainly primary visual cortex (V1), and ‘global’ or coherent patterns thought to activate higher cortical visual association areas (V3, V5, etc.). We studied three groups of children: (1) 19 children with CVI (mean age 9y 6mo [SD 3y 8mo]; 9 male; 10 female); (2) 40 neurologically and visually normal comparison children (mean age 9y 6mo [SD 3y 1mo]; 18 male; 22 female); and (3) because strabismus and amblyopia are common in children with CVI, a group of 41 children without neurological problems who had visual deficits due to amblyopia and/or strabismus (mean age 7y 8mo [SD 2y 8mo]; 28 male; 13 female). Results We found that the processing of global as opposed to local motion was preferentially impaired in individuals with CVI, especially for slower target velocities (p=0.028). Interpretation Motion processing is impaired in children with CVI. ssVEP may provide useful and objective information about the development of higher visual function in children at risk for CVI.
Solar Prominence Eruption

The prominence that erupts in a prominence eruption is a magnetic structure in the chromosphere and corona. It is visible in chromospheric images by virtue of chromospheric-temperature plasma suspended in the magnetic field, and belongs to that large class of magnetic structures appropriately called filaments because of their characteristic sinewy sigmoidal form. Hence, the term "filament eruption" is used interchangeably with the term "prominence eruption". The magnetic field holding a filament is prone to undergo explosive changes in configuration. In these upheavals, because the filament material is compelled by its high conductivity to ride with the magnetic field that threads it, this material is a visible tracer of the field motion. The part of the magnetic explosion displayed by the entrained filament material is the phenomenon known as a filament eruption, the topic of this article. This article begins with a description of basic observed characteristics of filament eruptions, with attention to the magnetic fields, flares, and coronal mass ejections in which erupting filaments are embedded. The present understanding of these characteristics in terms of the form and action of the magnetic field is then laid out by means of a rudimentary three-dimensional model of the field. The article ends with basic questions that this picture leaves unresolved and with remarks on the observations needed to probe these questions.
Odd Order Pandiagonal Latin and Magic Cubes in Three and Four Dimensions

Explicit algorithms are developed for constructing odd order n pandiagonal latin cubes in 3 and 4 dimensions, and these are used to construct pandiagonal magic cubes and 4 dimensional hypercubes, respectively. It is established that these structures exist in 3 dimensions only for odd orders n not less than 11, and in 4 dimensions only for odd orders n not less than 17. Estimates for the number of such structures as functions of n in 3 and 4 dimensions are also presented.
Heat Flow for Harmonic Maps

We examine the harmonic map heat flow problem for maps between the three-dimensional ball and the two-sphere. We give blow-up results for certain initial data, and establish convergence results for suitable axially symmetric initial data.
Psychophysiological Predictors of Working Alliance Among Treatment‐Seeking Women With Complex Trauma Exposure

Research has established that trauma-related symptoms may impede the formation of a strong working alliance (i.e., interpersonal connection, trust, and shared goals between therapist and client). As the alliance is critical in trauma-focused therapy, we studied how clients' pretherapy factors, including symptoms and psychophysiological arousal, predict treatment alliance. We examined symptoms and physiological responses in 27 women who had exposure to extreme interpersonal violence; all of whom were enrolled in therapy. All had symptoms consistent with a diagnosis of posttraumatic stress disorder. Clients completed measures of working alliance and were assessed before and after treatment on measures of symptoms and autonomic arousal. Autonomic assessment included measures of skin conductance and respiratory sinus arrhythmia (RSA), taken during baseline, while viewing positive and then trauma-related slides, and during recovery. Higher alliance ratings were predicted by lower pretherapy skin conductance during trauma slides (r = -.41, p = .049) and recovery (r = -.44, p = .047) and higher RSA during baseline (r = .47, p = .027) and positive slides (r = .43, p = .044). Findings remained significant even after partialling pretherapy symptoms. These data on a high-need but understudied population suggest that sympathetic and parasympathetic arousal may help traumatized clients effectively engage in therapy, further supporting the role of parasympathetic activity in social engagement.
Vulcanization and critical exponents

We consider a particular case of vulcanization of polymer chains in a semi dilute solution where a concentration p of vulcanizing agent has been added. This problem is equivalent to the percolation of elements having a functionality f depending both on the length N of the initial chains and on the monomer concentration C. Our approach allows us to take into account excluded volume effects as well as monomer concentration effects. We show that the critical percolation exponents can be observed under certain conditions. Whereas Flory's theory for vulcanization in the melt predicts a very small critical region and only mean field exponents can be observed in this case, we show that the width of the critical region, as well as the gel point, depend strongly on concentration. This allows us to consider the overlap concentration C* from a different point of view. We also discuss the swelling of these gels.
Langmuir Blodgett films of arachidic acid and a nematic liquid crystal: Characterization and use in homeotropic alignment

Abstract We study the behavior of a mixed Langmuir monolayer consisting of a fatty acid and a nematic liquid crystal. We demonstrate that the mixed monolayer successfully transfers as a Langmuir–Blodgett film and characterize the transferred film using UV spectroscopy. An important application of Langmuir–Blodgett films is in the alignment of liquid crystals for electro-optical applications, such as displays. We show that including the liquid crystal in the Langmuir–Blodgett film produces homeotropic alignment for a system which fails to align by other standard techniques.
Perspective on hypersonic nonequilibrium flow

Introduction O as well as new hypersonic flow programs continue to challenge the aerospace engineer. These programs are often of consuming difficulty, involving the synthesis of chemical kinetics, quantum mechanics, and radiation physics with fluid dynamics. To further complicate matters, the flowfield is often rarefied; thus the Knudsen number requires independent consideration along with the Mach and Reynolds numbers. Although these parameters are related, different regions of the flow, such as the interior of a bow shock, depend differently on them as compared with other regions. Because of its complexity, recent research has focused on the modeling of more realistic, complex hypersonic flows with the intensive use of computational fluid dynamics (CFD). Of necessity, the large codes used in this effort must resort to various empiricisms and approximations. Our objective in this Survey is to discuss some of these empiricisms and approximations within the context of hypersonic nonequilibrium flow. The issues and advances examined are primarily chosen for their relevance to theoretical gasdynamics; however, this Review makes no claim to being comprehensive. The books by Anderson and Park provide background material for the discussion of current issues, including lessons learned from the design and operation of the Space Shuttle. Our presentation is partly based on a previous report, some of which was published elsewhere. An alternative discussion of some of the same material can be found in an article by Tirsky whose discussion is especially valuable for emphasizing hypersonic research by Russian workers, with greater emphasis given to engineering heat transfer predictions. Some of this work is not as well known in the western community as it should be. The importance of finite rate chemistry and the problem of fuel-air mixing to hypersonic airbreathing propulsion cannot be overemphasized. These topics, however, are omitted from our discussion in as much as they fall under combustion gasdynamics and ought to be examined in this context.' The treatise on hydrogen combustion presented in Ref. 8 should be of interest to scramjet propulsion researchers. A broad perspective on hypersonic airbreathing vehicle design may be found in a survey (to be three volumes) edited by Bertin et al. In the next section, nonequilibrium aerothermodynamics is discussed. Much of this section is concerned with energy exchange that involves the vibrational modes of diatomic molecules. The subsequent section reviews the modeling of rarefied hypersonic flows and their continuum extension. There is no shortage of approaches that are available, as well as open issues. These approaches encompass the direct simulation Monte Carlo (DSMC) method, NavierStokes (NS) equations, Burnett, or augmented Burnett equations, and the 13-moment equations. The review concludes with a few brief remarks.
Scale Returns in Communication and Elite Control of Organizations

It seems to be a broadly valid generalization that in organizations of any size the central decisions are made by a relatively small number of individuals. Before World War I, there was a considerable literature, associated with such names as Vilfredo Pareto, Gaetano Mosca, and Robert Michels, which argued in one form or another that power in organizations tends to be concentrated in the hands of small elites. This is true regardless of the intended purpose of the organization. The most striking analysis is Michels's study of the German Social Democratic party. An organization devoted by its nature to spreading political power widely among the entire working class was itself run by a relatively small and self-perpetuating group. Michels referred indeed to an "iron law of oligarchy." I raise the question of to what extent is this phenomenon of elite control, as I shall call it, explainable in terms of rational organization theory. That is, is there some sense in which elite control economizes on some resources used in the processes of organizational decision-making. The article is exploratory in nature; I have no specific models, but rather raise the questions and suggest the issues that should be addressed in the future by more specific models. I do indeed suggest the possibility that elite control is connected with economies of scale in the process by which information is communicated. Hence, it will pay to reduce the number of individuals among whom information is to be communicated and have each transmit more. However, to the extent that this proposition is true, it calls for new models of optimal commu
Mortality and morbidity with intraoperative radiotherapy for head and neck cancer

Abstract Objective: To critically evaluate the morbidity and mortality associated with intraoperative radiation therapy (TORT). IORT allows the delivery of large single-doses of radiation to a visible tumor bed with exclusion (or shielding) of critical normal structures from the treatment field. Morbidity and mortality associated with TORT has been directly studied in abdominal malignancies, but only briefly mentioned in the head and neck literature. Patients and Methods: At the Arthur G. James Cancer Hospital, The Ohio State University Medical Center, 53 patients with advanced head and neck cancer were treated with surgical resection and IORT. Twenty of these patients had intraoperative high-dose-rate (HDR) brachytherapy, whereas the remaining 33 received intraoperative electron beam therapy. All patients received 7.5 to 20 Gy of radiation. Those treated were reviewed evaluating perioperative mortality, major and minor complications, and length of hospital stay. All patients have been followed at least 3 months postoperatively. Results: There were no perioperative deaths. Additionally, there was no increase in the number of complications or length of hospital stay associated with the use of IORT The mean length of hospital stay was 13.0 days. The major complication rate was 16.8%. Of the major complications, 9% were medical and not related to the surgical site. The minor complication rate was 8%. Conclusion: As we strive to increase control of advanced head and neck cancer, TORT may play an exciting role for intensifying the therapy. At this institution, TORT did not add to the mortality or morbidity of an aggressive multimodality treatment schema.
Topical vasoconstrictor use for nasal intubation during pregnancy complicated by cardiomyopathy and preeclampsia

Ankylosing spondylitis presents challenges for the obstetric anesthesiologist in administering neuraxial anesthesia or managing the airway. A pregnant patient with ankylosing spondylitis, cardiomyopathy and preeclampsia requiring cesarean delivery was managed with an awake nasotracheal fiberoptic intubation. The use of topical cocaine, epinephrine, phenylephrine, and oxymetazoline to produce nasal vasoconstriction is discussed. Selective alpha-2 agonists that can potentially provide nasal mucosa vasoconstriction and placental vasculature vasodilation are also discussed.
Teaching Economics in the 1980s.

Solow examines the seeming disarray of the economics profession, particularly with regard to macroeconomics, and attempts to indicate why this should be the case. He concludes with a bit of advice and a brief list of objectives for the first course in economics.
Use of multiple fluorophores for evaluating microvascular permeability in control rats and rats with sepsis.

Capillary leak accompanying systemic inflammatory response conditions is a significant clinical problem. In the present study, we describe and verify a method for studying capillary leak that is based on the injection of proteins that differ significantly in size and have spectrally distinguishable fluorophores. Control (n= 11) and post-CLP (caecal ligation and puncture; n= 14) Sprague-Dawley rats were injected with tracer amounts of albumin and PEG-Alb [albumin covalently linked to methoxy-poly(ethylene glycol)] labelled with fluorescein and Texas Red. Blood samples were withdrawn between 5 min and 144 h, and the fluorescence of the labelled proteins was determined. The relative retention of the PEG-Alb and albumin was assessed via measurement of the TER (transcapillary escape rate; in %/h) and the t 50% estimate, defined as the time when the actual concentration reached 50% of its baseline. The concentration-time trends for both albumin and PEG-Alb tracers exhibited two-compartmental behaviour and were analysed using biexponential modelling. Retention times were significantly greater for PEG-Alb in both control and CLP rats. TER PEG-Alb was significantly lower than TER albumin for both control (8.1 ± 5.6 compared with 14.8 ± 7.1 %/h respectively; P<0.01) and CLP (14.8 ± 6.6 compared with 22.5 ± 7.3 %/h respectively; P<0.001) rats. The t 50%[PEG-Alb] was substantially greater than the corresponding t 50%[albumin] for both control (29.8 ± 9.8 compared with 7.2 ± 2.0 h respectively; P<0.001) and CLP (12.9 ± 5.6 compared with 5.1 ± 1.6 h respectively; P < 0.001) rats. The result was similar irrespective of the fluorophore-protein combination, validating the multifluorophore technique. In conclusion, the double-fluorophore approach described in the present study may provide the future basis for a method to quantify capillary leak in disease.
Na+ and Cl− transport across polyimide films

Na+ and Cl- transport across 2.4- and 5.2-μm-thick polyimide (PI) PMDA/ODA and 7.5-μm-thick du Pont Kapton films was studied in a diffusion cell using ion-selective electrodes. The temperature was 30°C. Diffusion coefficients Dm (in cm2/s), permeability coefficients P (in cm2/s), and distribution coefficients K were obtained by applying the time lag analysis on the ion uptake transient in the acceptor compartment of the diffusion cell. Both Na+ and Cl- were observed to diffuse across PI. Diffusion coefficients varied in the range 10-12-10-13 cm2/s whereas ionic permeability results showed more scatter ranging from 1 X 10-11 to 8 X 10-14 cm2/s. The latter discrepancy was ascribed to diffuse heterogeneities on the order of 0.5 μm. No significant ionic selectivity between Na+ and Cl- was observed. This result indicates the absence of ionic fixed charge (unreacted polyamic acid) in the polymeric matrix. An attempt is made to determine the effect of water sorption mode and contaminants in the film on the ionic permeabilities data.
Tri- and tetra-meric phosphonitridic fluoride☆

Abstract The tri- and tetra-meric phosphonitridic fluoride (PNF 2 ) 3 and (PNF 2 ) 4 , respectively, can be easily obtained in satisfactory yields by reacting the corresponding phosphonitridic chlorides with argentous fluoride. The mass spectrum proves the assumed cyclic structure for both compounds.
Field techniques for exposure of plants and ecosystems to elevated CO2 and other trace gases

Carbon dioxide (CO{sub 2}) concentration of the atmosphere has varied considerably over geological time. Ice core data from the USSR Vostok Station showed that the Earth`s atmospheric CO{sub 2} ranged from as low as 180 to 200 {mu}mol mol{sup {minus}1} during the last two glacial maxima (13,000 to 40,000 and 130,000 to 160,000 years before present). However, following the rapid glacial melting, the concentration rose quickly to about 260 to 270 {mu}mol mol{sup {minus}1}. Since around 1700 AD, the CO{sub 2} concentration has increased from about 270 {mu}mol mol{sup {minus}1} to 315 {mu}mol mol{sup {minus}1} in 1958 and 355 {mu}mol mol{sup {minus}1} in 1991. 209 refs., 4 figs., 2 tabs.
SMALL APERTURE COUPLING BETWEEN DISSIMILAR REGIONS

The small aperture coupling theory is improved by introducing the radiation reaction fields as part of the polarizing field acting on the aperture. The principles of power conservation and reciproc...
EXPOSURE TO MIXTURES OF NITROGLYCERIN AND ETHYLENE GLYCOL DINITRATE.

Abstract Combined measurements of air and skin exposures and medical examination of workers were undertaken in an explosives manufacturing plant. Evidence is presented that ethylene glycol dinitrate and nitroglycerin are not only respiratory, but also skin hazards which can be measured environmentally and by medical methods. The suggestion is made for study of skin exposures by standardized use of lining gloves with or without plastic disposable gloves. The authors urge that methods be undertaken to standardize skin exposure measurements. The importance of the hazard through skin exposure is emphasized relative to setting and interpreting threshold limit values.
Simulation of an early warning system using sentinel birds to detect a change of a low pathogenic avian influenza virus (LPAIV) to high pathogenic avian influenza virus (HPAIV).

Abstract The placement of sentinel birds in a commercial poultry flock infected with low pathogenic avian influenza virus (LPAIV) may be an effective way of detecting subsequent change in the isolate to a high pathogenic avian influenza virus (HPAIV). Data collected from the 2002 Chilean HPAIV outbreak, along with information from a literature review of laboratory studies involving A/chicken/Chile/176822/02 (H7N3/LP) and A/chicken/Chile/184240-1/02 (H7N3/HP) viruses, were used to construct a computer simulation model. Mortality rates of the original LPAIV-infected population and the sentinel population were compared to detect the presence of HPAIV. A total of 12 increased mortality threshold scenarios were examined, using one-day absolute (2, 3, or 4 birds) or relative (0.5, 1.0, or 1.5%) mortality thresholds, and two-day absolute (1, 2, or 3 birds) or relative (0.25, 0.50, or 1.00%) mortality thresholds, to indicate the change from LPAIV to HPAIV in the sentinel and original populations, respectively. Results showed that following a one-day approach, threshold mortalities occurred on average at 7.35, 7.82, and 8.17 (0.5, 1.0, or 1.5%) and 6.21, 6.38, and 6.45 (2, 3, or 4 birds) days after the first infectious case for the original and sentinel populations, respectively. The two-day approach delayed the occurrence of threshold mortalities, on average, to 7.64, 8.05, and 8.62 (0.25, 0.50, or 1.00%) and 6.86, 6.78, and 7.23 (1, 2, or 3 birds) days after the first infectious case for the original and sentinel populations, respectively. Although, significant ( p
Adaptive post-buckling response of carbon fibre composite plates employing SMA actuators

Abstract Restoration forces, associated with embedded activated pre-strained SMA wires, have successfully been employed to enhance the post-buckling behaviour of laminated plate structures while under the influence of a uniaxial load. The results of which will be presented. The manufacturing methodology of the hybrid SMA-carbon-epoxy plates is outlined. Optical micrographs illustrate the effect of embedding diametrical inclusions within a host composite. Thermal and structural finite-element analysis have been employed to predict the non-uniform temperature profile within the laminates and to provide insight to the SMA-hybrid structure adaptive response. It is shown that by utilizing the considerable control authority generated, even for a small actuator volume fraction, the out-of-plane displacement of the post-buckled laminates can be significantly reduced. Such displacement alleviation allows for the load redistribution away from the plate's unloaded edges i.e. there is a tendency for the plate to conform to the optimal flat configuration beyond its critical buckling load. However, the stability of the adaptive response is very much dependent upon the laminate stacking sequence. It is envisaged that the range of operational performance for such an adaptive hybrid structure may be extended over conventional materials and structures.
Guardianship planning among HIV-infected parents in the United States: results from a nationally representative sample.

OBJECTIVE.The purpose of this work was to determine the rates and predictors of guardianship planning and preferred guardians among HIV-infected parents. PARTICIPANTS AND METHODS.Data were analyzed from interviews with 222 unmarried parents (who had 391 children) from a nationally representative sample of HIVinfected adults receiving health care. Outcome measures included parental report on the level of guardianship planning and on who their preferred guardian for each child was. Level of guardianship planning was categorized as follows: (1) parent had not identified a guardian; (2) parent had identified a guardian, but the guardian had not agreed; (3) identified guardian had agreed; and (4) legal documentation of guardianship plan was complete. We conducted bivariate and ordered logistic regression analyses on the level of guardianship planning and multinomial logistic regression on identification of preferred guardians. RESULTS.Twelve percent of unmarried HIV-infected parents had not identified a guardian; 6% had identified a guardian but gone no further; 53% said the identified guardian had agreed; and 28% had prepared legal documentation. The preferred guardians included other biological parents (17%), spouse/partners who were not biological parents (2%), grandparents (36%), other relatives (34%), friends (7%), unrelated adoptions (1%), and others (3%). Parents with the lowest CD4 counts and parents living without other adults were more likely to have completed the guardianship planning process. Nonrelatives were most often preferred by mothers and parents with higher CD4 counts; grandparents were most often preferred by younger parents and parents who prefer speaking Spanish. CONCLUSIONS.Pediatricians and others who take care of children with HIV-infected parents may be able to provide counseling and referrals for guardianship planning.