cssi/SciSciGPT-SciSciNet huggingface dataset:
c-Abl kinase regulates the protein binding activity of c-Crk.

Abstract c-Crk is a proto-oncogene product composed largely of Src homology (SH) 2 and 3 domains. We have identified a kinase activity, which binds to the first Crk SH3 domain and phosphorylates c-Crk on tyrosine 221 (Y221), as c-Abl. c-Abl has a strong preference for c-Crk, when compared with common tyrosine kinase substrates. The phosphorylation of c-Crk Y221 creates a binding site for the Crk SH2 domain. Bacterially expressed c-Crk protein lacks phosphorylation on Y221 and can bind specifically to several proteins, while mammalian c-Crk, which is phosphorylated on tyrosine, remains uncomplexed. The protein binding activity of c-Crk is therefore likely regulated by a mechanism similar to that of the Src family kinases. v-Crk is truncated before c-Crk Y221 and forms constitutive complexes with c-Abl and other proteins. Our results suggest that c-Abl regulates c-Crk function and that it could be involved in v-Crk transformation.
Analytic Modal Tableaus and Consistency Properties

The ideas underlying the tableau rules of Chapter One #4 are simple. We know that if Γ is a possible world in a Kripke model, and if Γ ╟ α then Γ ╟ α and Γ ╟ α2. Likewise if Γ ╟ β then Γ ╟ β1 or Γ ╟ β2. The tableau rules obviously reflect these facts bout models. (Indeed, this will be the basis of a correctness proof in #3.)
Single-cell responses to three-dimensional structure in a functionally defined patch in macaque area TEO

We recorded in a part of the macaque area TEO that is activated more by curved surfaces than by flat surfaces at different disparities using the same stimuli. In contrast to previous studies, this ...
An Object Oriented Graphical User Interface (GUI) for Optimal Placement of Phasor Measurement Units

The placement of Phasor Measurement Units (PMUs) and Smart Meters have become key components for smart grids to monitor system behaviours in real-time. The optimal PMU placement is key for a smart grid system for its secure operation. This paper presents an object-oriented programming (OOP) approach combined with GLPK (GNU Linear Programming Kit), to solve for optimal number of PMUs for any grid size. This is done through an external library called Glpk.js, which is a JavaScript port of the GLPK. The code is made available as opensource for simulation and analysis of bus networks using a Graphical User Interface (GUI). The code is easily scalable to any size network for any sensor placement problem. The graphical approach makes it easier for any researcher or grid operator to analyse the system for optimal sensor placement locations.
The efficacy of trunk injections of emamectin benzoate and phosphorous acid for control of obliquebanded leafroller and apple scab on semi-dwarf apple

Abstract Trunk injections reduce pesticide inputs and environmental contamination, and recent work has addressed apple production systems. Insecticides and fungicides have been demonstrated for apple tree injection, however combinations of the two have not yet been tested. Trunk injections of the systemic insecticide emamectin benzoate and systemic acquired resistance (SAR) fungicide phosphorous acid were performed on mature apple trees to combine management strategies for foliar insect pests and apple scab (Venturia inaequalis). Injections of emamectin benzoate followed by phosphorous acid into the same set of injection ports resulted in higher mortality of Choristoneura rosaceana larvae and lower incidence of apple scab compared to the control. Scab incidence on trees in which phosphorous acid was injected into the same set of ports before emamectin benzoate were not different from control trees early in the growing season. Injections of emamectin benzoate and phosphorous acid into the same holes in either order showed higher mortality and reduced larval feeding in C. rosaceana bioassays compared with products injected into separate holes. This study demonstrates that two pesticides can interact dynamically within the vascular system of a tree, which has important implications for expanding the utility of trunk injection for fruit tree management.
(131) Impact of an Interactive Music App on Pain Threshold, Temporal Summation, and Conditioned Pain Modulation in Healthy Volunteers

Music has been shown to decrease pain and modulate affect, but the mechanism by which music conveys analgesia in relatively unexplored . Using quantitative sensory testing (QST), we assessed the impact of a novel app-based music intervention on the nociceptive processing of pain. Healthy volunteers (n=60) were assessed for psychosocial traits including anxiety, depression, and catastrophizing using validated questionnaires. QST included investigation of: 1) pain sensitivity as measured by pressure pain threshold and tolerance using a handheld algometer, as well as reported pain to weighted pinprick stimuli, 2) temporal summation of pain (TSP) with a repeated pinprick stimulus, and 3) conditioned pain modulation (CPM) with pressure and cold stimuli. QST was performed in both the absence and presence of an interactive music app (Unwind), with paired t or Wilcoxon rank tests used to determine differences. Pressure pain threshold in both the forearm (p=0.007) and trapezius (p=0.002) increased with music. Initial pinprick pain severity (p
Lack of tumor reduction in hyperprolactinemic women with extrasellar macroadenomas treated with bromocriptine.

Three patients with hyperprolactinemia and large extrasellar pituitary macroadenomas were treated with bromocriptine, 10 mg daily, for 8 weeks. In spite of correction of their amenorrhea, galactorrhea, and hyperprolactinemia, radiologic evaluation by CT scan failed to show evidence of tumor shrinkage. After surgical resection, histologic examination revealed that PRL-secreting cells comprised only a small portion of the tumor cell population in two patients and in the third patient were completely absent. These cases illustrate that large nonfunctional pituitary tumors may mimic signs and symptoms of a prolactinoma and stress the importance of adequate radiologic evaluation during medical management. 8 references, 3 figures.
“Primitive Sounds”: An Examination of the Conflicting Discourse in the Early British Reception of Igor Stravinsky’s Russian Ballets

ABSTRACTIgor Stravinsky’s ballet The Firebird was an immediate success upon its arrival in London in 1912. Nevertheless, as Stravinsky’s music evolved with each subsequent ballet, his British recep...
Consensus guidelines for thoracic surgical patient management—do they represent the consensus?

Definitive surgery for esophageal cancer is associated with a high rate of postoperative complications. For instance, in the NSQIP database (2008 to 2017), the average rate of 30-days mortality and overall morbidity after a 3-field esophagectomy (CPT 43112) is 2.7% and 47.4%. Further, pulmonary complications (pneumonia, prolonged intubation and reintubation within 72 hours) occur with a rate of 26.0%, and infectious complications (superficial, deep, organ space surgical site infections, dehiscence, sepsis) occur with a rate of 23.6%. These are 2.6%, 42.3%, 23.1%, and 16.8% after Ivor Lewis esophagectomy (CPT 43117), and 2.5%, 44.0%, 25.1%, and 22.0% after transhiatal esophagectomy (CPT 43107) (1). Thus, these are one of the cruxes of esophagectomy.
Prediction at the Discourse Level in Spanish-English Bilinguals: An Eye-Tracking Study.

In two experiments, we examine English monolinguals’ and Spanish-English bilinguals’ ability to predict an upcoming pronoun referent based on the Implicit Causality (IC) bias of the verb. In an eye-tracking experiment, the monolingual data show anticipation of the upcoming referent for NP1-bias verbs. For bilinguals, the same effect is found, showing that bilinguals are not slower than monolinguals at processing the information associated with the IC of the verb. In an off-line experiment, both groups showed knowledge of IC bias information for the verbs used in the eye-tracking experiment. Based on the findings of the two experiments, we show that highly proficient bilinguals have similar online and off-line predictions based on IC verb information than monolingual speakers.
Bayesian evaluation of a physiologically based pharmacokinetic (PBPK) model for perfluorooctane sulfonate (PFOS) to characterize the interspecies uncertainty between mice, rats, monkeys, and humans: Development and performance verification.

Abstract A challenge in the risk assessment of perfluorooctane sulfonate (PFOS) is the large interspecies differences in its toxicokinetics that results in substantial uncertainty in the dosimetry and toxicity extrapolation from animals to humans. To address this challenge, the objective of this study was to develop an open-source physiologically based pharmacokinetic (PBPK) model accounting for species-specific toxicokinetic parameters of PFOS. Considering available knowledge about the toxicokinetic properties of PFOS, a PBPK model for PFOS in mice, rats, monkeys, and humans after intravenous and oral administrations was created. Available species-specific toxicokinetic data were used for model calibration and optimization, and independent datasets were used for model evaluation. Bayesian statistical analysis using Markov chain Monte Carlo (MCMC) simulation was performed to optimize the model and to characterize the uncertainty and interspecies variability of chemical-specific parameters. The model predictions well correlated with the majority of datasets for all four species, and the model was validated with independent data in rats, monkeys, and humans. The model was applied to predict human equivalent doses (HEDs) based on reported points of departure in selected critical toxicity studies in rats and monkeys following U.S. EPA's guidelines. The lower bounds of the model-derived HEDs were overall lower than the HEDs estimated by U.S. EPA (e.g., 0.2 vs. 1.3 μg/kg/day based on the rat plasma data). This integrated and comparative analysis provides an important step towards improving interspecies extrapolation and quantitative risk assessment of PFOS, and this open-source model provides a foundation for developing models for other perfluoroalkyl substances.
The Efficient Queue and the Case Against Dynamic Pricing

Surge pricing—using data and algorithms to raise prices in response to unexpected increases in demand—has spread across the economy in recent years, from Amazon, to Disney World, to commuter highways, not to mention Uber, which is infamous for surge pricing rides. Companies claim that surge pricing equilibrates supply and demand, but that is impossible, at least in the short run when demand unexpectedly outstrips supply. What surge pricing really does is to ration existing supplies based on ability to pay. That is both distributively unjust and potentially inefficient. It is also anticompetitive in the sense that it reduces the power of the competitive pricing that prevails before a surge in demand to carry over into the surge period. As such, surge pricing is similar in effect to price fixing, which also prevents competitive pricing from carrying over into periods during which firms have obtained power to raise prices. Courts should therefore rule surge pricing per se illegal under the antitrust laws, just as they do price fixing today.
Creating a Library Logo for an Academic Library

Memorial Library at Minnesota State University, Mankato needed a new library logo to replace one that was 25 years old and which did not reflect the library's current program. This article discusses the role of a logo in conveying an organization's identity, and describe the entire process of developing, producing, and implementing a new logo for the library.
Photovoice as a Multilevel Tool for Gender and Sexual Identity Exploration

Gender and sexual identity exploration (GSIE) consists of engaging in activities that allow an individual to discover their values, preferences, and boundaries related to gender and sexuality. Phot...
Malware Analytics: Review of Data Mining, Machine Learning and Big Data Perspectives

Recent advances in cyber technologies have made human life’s easier, but it may lead to a heavy cost in terms of economic, psychological or reputation damage. For instance, these damages may be caused by variants of malware propagated in a hidden and mostly untraceable way. Malware analytics deals with the approaches and techniques utilized to generate the distinguishing characteristics of the malware for robust cyber defenses. This paper aims at presenting the current status of the malware research, challenges, and methods used to overcome those challenges using data mining, machine learning and big data perspectives. We have considered these three perspectives because of its extensive computation value, mostly fused to solve a wide range of problems from security to medical, finance and industry. These domains as an independent technique and their interrelationships depend on the nature of the dataset considered. We have also proposed a framework to overcome the challenges and open issues prevalent in malware analytics. It is hoped that this paper with the simplified presentation of the most vital approaches of malware analytics will help the inspiring researcher or a newbie in the security field to explore more as well as budding engineers to choose malware analysis as their field of study. Specifically, analysis of state-of-the-art approaches with evaluation, pros and cons discussion and the current challenges and future directions will empower all the malware enthusiasts.
A Systematic Review of Organizational and Workforce Interventions to Improve the Culture and Climate of Youth-Service Settings

Both organizational culture and climate are associated with service quality and outcomes across youth-service settings. Increasing evidence indicates capacity of organizational interventions to promote a positive and effective culture and climate. Less is known about common intervention components across studies and service settings. The current systematic review reviewed 9223 citations and identified 31 studies, across six youth-service settings, measuring changes over time in organizational culture and climate following implementation of an organizational or workforce support intervention. Results highlight the promise of organizational interventions, a need for more comparison and randomized designs, and future directions for maximizing capacity of organizations to promote health for frontline providers and the children they serve.
Examination of PD-1/PD-L1 inhibitor use and adverse events in a real-world setting.

e19294Background: Immune checkpoint blockade through PD-1 and PD-L1 inhibition is an effective treatment for multiple cancers. This study used administrative claims to examine potential adverse eve...
Rebel Territorial Control and Civilian Collective Action in Civil War: Evidence from the Philippines

Under what conditions do rebel organizations control territory during civil war? How do civilians influence the distribution of territorial control? This article introduces a civilian agency theory, emphasizing community collective action capacity (CAC) defined by underlying social network structure, to complement existing explanations of territorial control. I argue communities with greater CAC mobilize information and resources more efficiently, increasing belligerents’ incentives to control territory. However, CAC also increases community bargaining power to demand costly investments in governance, partially offsetting these gains. CAC increases rebel control in areas of state neglect. But, as state service provision increases, communities leverage CAC to demand prohibitively costly rebel governance, deterring rebel control. The article tests the theory in the context of the communist insurgency in the Philippines, using military intelligence reports from 2011-2014 to measure village-level communist insurgent territorial control and a household-level census (2008-2010) to measure village CAC. Interviews with village elders in Eastern Mindanao illustrate causal mechanisms and explore alternative explanations.
Correcting United States payments imbalances: taxing foreign holders of its treasury securities is better than import tariffs

To correct US current account deficits, dollar depreciation rather than imposition of tariffs is economically the better response. The theory of second best (The Review of Economic Studies, 24, 11) implies that if there is only one distortion then correct it, but the welfare effects of adding a second, supposedly offsetting distortion, may not increase welfare and can reduce it. In the context of an overvalued dollar caused by the dollar's status as the predominant global investment currency—a distortion adversely affecting the US manufacturing sector, the first best policy is not to impose tariffs because this adds a trade distortion on top of an exchange rate distortion and can easily be welfare reducing. US imports may be diverted from China to higher‐cost foreign producers not subjected to the tariff, and tariffs do nothing to promote US exports. The first best policy is directly to reduce the distortion of an overvalued exchange by discouraging excessive accumulation of foreign holdings of US securities held as foreign exchange reserves and by foreign private investors. A tax on the foreign holdings is a way to accomplish this.
Rapid Estimation of Entire Brain Strain Using Deep Learning Models

Objective: Many recent studies suggest that brain deformation resulting from head impacts are linked to the corresponding clinical outcome, such as mild traumatic brain injury (mTBI). Even if several finite element (FE) head models have been developed and validated to calculate brain deformation based on impact kinematics, the clinical application of these FE head models is limited due to the time-consuming nature of FE simulations. This work aims to accelerate the brain deformation calculation and thus improve the potential for clinical applications. Methods: We propose a deep learning head model with a five-layer deep neural network and feature engineering, and trained and tested the model on 2511 head impacts from a combination of head model simulations and on-field college football and mixed martial arts impacts. Results: The proposed deep learning head model can calculate the maximum principal strain (Green Lagrange) for every element in the entire brain in less than 0.001 s with an average root mean squared error of 0.022 and a standard deviation of 0.001 over twenty repeats with random data partition and model initialization. Conclusion: Trained and tested using the dataset of 2511 head impacts, this model can be applied to various sports in the calculation of brain strain with accuracy, and its applicability can even further be extended by incorporating data from other types of head impacts. Significance: In addition to the potential clinical application in real-time brain deformation monitoring, this model will help researchers estimate the brain strain from a large number of head impacts more efficiently than using FE models.
Television Viewing, Physical Activity, and Loneliness in Late Life.

Background and objectives Television viewing is the most common leisure activity in late life and may ease loneliness but encourage sedentary behavior. These associations may be particularly evident among older adults who live alone and who may lack other forms of companionship throughout the day. Research design and methods Adults aged 65+ (N = 257) participated, of whom 34% lived alone. Participants completed an initial interview followed by a 5- to 6-day data collection involving multi-methods: (a) Electronically Activated Recorders (EAR) (30 seconds every 7 minutes) provided audio recordings of television viewing, (b) Actical accelerometers objectively measured physical activity, and (c) ecological momentary assessments (EMA) every 3 hours assessed social interactions. Results On average, older adults spent approximately 37% of their waking time (6.4 hours a day) watching television. Multilevel models revealed that television viewing occurred when participants were alone or with a spouse and was associated with a greater proportion of time sedentary, lower activity, and higher ratings of loneliness compared to when not watching television. Older adults who lived alone reported greater loneliness during 3-hour intervals when viewing television, but older adults who lived with others spent a greater proportion of time sedentary when viewing television. Discussion and implications Findings are discussed with regard to different rationales and ways of watching television - as compensation for social isolation or as a passive leisure activity with a social partner. We discuss ideas for research on additional aspects of television viewing and screen time in late life.
Owning All the Seeds: Consolidation and Control in Agricultural Biotechnology

Agricultural companies are merging at a remarkable rate. The ensuing ag-biotech behemoths will have unprecedented control over global food production. The companies claim that this industry consolidation will not only benefit shareholders, but will serve the public by promoting food security and environmental sustainability. This Article tests those claims and finds them wanting.
Empowering Culture Change: Internationalization in the Academic Department

Internationalization of higher education has widespread benefit to society and has become the expected norm. The literature offers many calls for and models of comprehensive internationalization. Society expects higher education graduates to be global ready when they graduate. Responsible citizenship and professional life require that people be inclusive and sensitive to the worldviews of others. Those calls for change raise an opportunity: a model for culture change to be followed by others. University programming is centered at the department, which is the center of faculty life (e.g., teaching, curricular change, interaction with peers, promotion and tenure). The academic department is the center of institutional change. We used a three-year, inclusive process, to develop a strategic, international, intercultural plan for a department in a comprehensive US university. Our plan includes four themes, complemented by 12 goals. Each goal has actions with time frames (i.e., 1-3 years, 5-7 years, 10-12 years). There are 49 total actions. Among those, 28 are in the 1-3 year time frame, and each of those has a responsible actor (e.g., individual or committee). The plan is adaptive, and includes assessment to advance accountability and transparency. We began implementation coincident with the pandemic, and with significant social unrest in our community and nation. The year of experience provided both affirmation and redirection. Our model guides departmental change, empowering necessary growth and offering a model for others wishing to advance internationalization.
Psychotherapy with Older Adults

Compared to the general population, older adults often experience greater excess disability due to a variety of emotional disturbances and formal psychiatric disorders. There is increasing evidence that much of this unnecessary suffering can be ameliorated by a variety of psychotherapeutic interventions (Teri & McCurry, 1994). However, there are factors unique to older adults that affect the recognition of emotional disorders in late life as well as the availability, delivery, and effectiveness of mental health services. This chapter begins with an overview of key issues relevant to psychotherapy with older adults, beginning with accessibility and utilization of mental health services in this population. This is followed by a selective review of relevant clinical, empirical, and theoretical issues in the diagnostic categories of late-life depression, anxiety, and substance abuse. The chapter concludes with a discussion of suggested guidelines for therapeutic interventions with older adults, with particular attention to psychiatric disability in individuals with neurological disorders.
Adrenocortical Control of Epinephrine Synthesis in Health and Disease

Publisher Summary This chapter discusses adrenocortical control of epinephrine synthesis in health and disease. All species of vertebrates contain innervated cells that are derived from the neuroectoderm. However, only in mammals, chromaffin cells form a compact body, the adrenal medulla that takes on an envelope or cortex of steroid-secreting tissue during embryonic life. The cells of the adrenal cortex differ vastly from chromaffin cells: their embryonic anlage is not neuroectoderm but coelomic epithelium; they do not synthesize not water-soluble amines but lipid-soluble steriods and secrete them not in response to neuronal inputs but to a circulating hormone. The adrenal glands of mammals contain two distinct zones: (1) an outer cortex, which is homologous with the interrenal glands of lower vertebrates and which synthesizes glucocorticoid and mineralocorticoid hormones and (2) an inner medulla that is composed of chromaffin cells, which synthesizes norepinephrine and epinephrine. In certain species, these two zones are partially divided by an X-zone, which can secrete androgenic hormones. Otherwise, no capsule or sharp boundary separates the chromaffin cells from the steroid-producing cells.
Whither the Psychology of Religion: A Spirituality-Focused Discussion of Paloutzian and Park’s (2005)

Presuming Rayburn’s (2006: Child & Family Behavior Therapy, 28, 86–92) review of (Paloutzian and Park, 2005, Handbook of the psychology of religion and spirituality. New York: The Guilford Press) and sketching an alternative paradigm, this review focuses on the Handbook’s virtual conflation of religion and spirituality; relates this conflation to the hegemony of Protestant theology in North American psychology of religion; highlights the Handbook’s neglect of spirituality per se, which, if not inseparably linked with theism, is, nevertheless, related to the self-transcending, meaning-making dimension of the human mind, could provide an explanatory breakthrough in the field of the psychology of religion and of the social sciences overall; and sees Handbook’s advocacy for a “multilevel interdisciplinary paradigm” as a regrettable acceptance of the failed, long-term strategy of the field of psychology in general.
Immortalizing Central Nervous System Cells

This unit presents methods for isolating clonal, neural-derived cell lines. One approach for isolating such neural cell lines involves a replication-deficient retrovirus encoding a specific oncogene and a selectable marker which are used to infect dissociated CNS cells dissected at a developmental stage at which the cell population of interest has not undergone its terminal mitotic division. Also presented is a method for cloning by limiting dilution, which may be necessary to obtain a pure population of cells. Following growth under appropriate selection conditions, clones are isolated and tested for their ability to differentiate with the desired phenotypic properties. A method is also provided for coating tissue culture dishes, which is necessary for successful culture of CNS neurons.
Comparison of the folding of 2-Keto-3-deoxy-6-phosphogluconate aldolase, triosephosphate isomerase and pyruvate kinase: Implications in molecular evolution

Abstract The 8-fold α/β barrel conformation of 2-keto-3-deoxy-6-phosphogluconate aldolase has been compared to that of triosephosphate isomerase and the A-domain of pyruvate kinase. There are eight supersecondary structure units (α/β) in each of these proteins, and the comparisons were carried out in orientations corresponding to each of the possible congruences, i.e. first to first, first to second,… of the supersecondary structure units. The comparison of the C α structure of the main chain folding of the three enzymes indicated about 150 equivalences with rootmean-square differences of about 3.1 A, with no orientational preference, including the aldolase with itself. In addition, there is no sequence homology between the aldolase and the isomerase, and no indication of gene duplication in the former. The lack of orientational preference among the three enzymes suggests convergence to a fold of exceptional stability. However, all three enzymes activate a CH bond adjacent to a carbonyl, and their active sites correspond to the f strand, F helix region of the α/β barrel, thus contradicting the foregoing and suggesting divergent evolution from a common precursor. Other and similar arguments are also presented for and against convergent evolution of these three strikingly similar enzymes.
Transform Methods for Solving Partial Differential Equations

THE FUNDAMENTALS Fourier Transforms Laplace Transforms Linear Ordinary Differential Equations Complex Variables Multivalued Functions, Branch Points, Branch Cuts, and Riemann Surfaces Some Examples of Integration which Involve Multivalued Functions Bessel Functions What are Transform Methods? METHODS INVOLVING SINGLE-VALUED LAPLACE TRANSFORMS Inversion of Laplace Transforms by Contour Integration The Heat Equation The Wave Equation Laplace's and Poisson's Equations Papers Using Laplace Transforms to Solve Partial Differential Equations METHODS INVOLVING SINGLE-VALUED FOURIER AND HANKEL TRANSFORMS Inversion of Fourier Transforms by Contour Integration The Wave Equation The Heat Equation Laplace's Equation The Solution of Partial Differential Equations by Hankel Transforms Numerical Inversion of Hankel Transforms Papers Using Fourier Transforms to Solve Partial Differential Equations Papers Using Hankel Transforms to Solve Partial Differential Equations METHODS INVOLVING MULTIVALUED LAPLACE TRANSFORMS Inversion of Laplace Transforms by Contour Integration Numerical Inversion of Laplace Transforms The Wave Equation The Heat Equation Papers Using Laplace Transforms to Solve Partial Differential Equations METHODS INVOLVING MULTIVALUED FOURIER TRANSFORMS Inversion of Fourier Transforms by Contour Integration Numerical Inversion of Fourier Transforms The Solution of Partial Differential Equations by Fourier Transforms Papers Using Fourier Transforms to Solve Partial Differential Equations THE JOINT TRANSFORM METHOD The Wave Equation The Heat and Other Partial Differential Equations Inversion of the Joint Transform by Cagniard's Method The Modification of Cagniard's Method by De Hoop Papers Using the Joint Transform Technique Papers Using the Cagniard Technique Papers Using the Cagniard-De Hoop Technique THE WIENER-HOPF TECHNIQUE The Wiener-Hopf Technique When the Factorization Contains No Branch Points The Wiener-Hopf Technique when the Factorization Contains Branch Points Papers Using the Wiener-Hopf Technique WORKED SOLUTIONS TO SOME OF THE PROBLEMS INDEX
Observation of the Dissociation of Unliganded Hemoglobin II. EFFECT OF PH, SALT, AND DIOXANE

Abstract The dissociation constant for the tetramer-dimer equilibrium of unliganded hemoglobin (Ku4,2) has been measured under a variety of solvent conditions by means of the carbon monoxide-binding technique described in the first paper in this series. Under standard conditions (0.1 m phosphate, pH 7.0) the dissociation equilibrium is characterized by the constant Ku4,2 = 3 x 10-12 m. Experiments in 0.5, 1.0, and 2.0 m NaCl indicate a continuous enhancement of dissociation by the salt to give values for Ku4,2 of 9 x 10-12 m, 18 x 10-12 m, and 65 x 10-12 m, respectively. The value of Ku4,2 also increases with pH in roughly the manner expected from considerations of the Bohr effect of hemoglobin. In contrast, dioxane up to 2 m has a slight stabilizing effect on the unliganded tetramer. These results are interpreted in terms of the salt bridges postulated to play a major role in the stability of unliganded hemoglobin tetramers and the cooperative interactions between hemoglobin and its ligands.
Sensemaking: Beyond the Servo Metaphor

Since Wiener presented the Cybernetic Hypothesis, the automatic control system has been an important metaphor guiding research on cognitive systems. This metaphor has helped us to appreciate goal orientation within cognitive systems. It has also helped us to appreciate the closed-loop nature of perception and action. However, as with any metaphor, there are important limitations with respect to the phenomenon being represented - in this case, the dynamics of cognitive systems or the dynamics of sensemaking. One important limitation is that the source of goals and values is extrinsic to automatic control systems, but an intrinsic aspect of sensemaking. A second limitation is that the control and observation problems tend to be modularized in automatic control systems. In this context, the observation problem is reduced to the information-processing problem of filtering signal from noise. This tends to underplay the abductive dynamics of meaning processing that are essential to adaptation in a changing world. Finally, the servo metaphor tends to focus attention on the information processing system as a `mechanism? apart from its environment. This tends to underplay the tight coupling between agent and environment both in terms of constraining relations and emergent properties. It is time to move beyond the servo metaphor. However, the analytic tools of control theory will become even more important as we explore the more complex dynamics of sensemaking.
Ultrastructural localization of osteopontin immunoreactivity in phagolysosomes and secretory granules of cells in human intestine.

A post-embedding ultrastructural immunogold method was used to detect osteopontin in human intestinal biopsies with special emphasis on secretory and phagocytic organelles. Osteopontin immunoreactivity was localized to phagolysosomes of macrophages, fibroblasts, absorptive epithelial cells of the small intestine and Paneth cells. The mucigen secretory granules and Golgi structures of mucous epithelial cells of the small intestinal epithelium contained osteopontin, but secretory granules of numerous other cells, including Paneth cells, did not. Extracellular and phagocytosed Tropheryma whippelii within macrophage phagolysosomes also bound osteopontin. These localizations are supportive of a role for osteopontin in phagocytic and some secretory cell functions in human intestine
Using tryptophan fluorescence to measure the stability of membrane proteins folded in liposomes

Accurate measurements of the thermodynamic stability of folded membrane proteins require methods for monitoring their conformation that are free of experimental artifacts. For tryptophan fluorescence emission experiments with membrane proteins folded into liposomes, there are two significant sources of artifacts: the first is light scattering by the liposomes; the second is the nonlinear relationship of some tryptophan spectral parameters with changes in protein conformation. Both of these sources of error can interfere with the method of determining the reversible equilibrium thermodynamic stability of proteins using titrations of chemical denaturants. Here, we present methods to manage light scattering by liposomes for tryptophan emission experiments and to properly monitor tryptophan spectra as a function of protein conformation. Our methods are tailored to the titrations of membrane proteins using common chemical denaturants. One of our recommendations is to collect and analyze the right-angle light scattering peak that occurs around the excitation wavelength in a fluorescence experiment. Another recommendation is to use only those tryptophan spectral parameters that are linearly proportional to the protein conformational population. We show that other commonly used spectral parameters lead to errors in protein stability measurements.
Basic Security Concepts

The computer security problem is an adversary problem: there is an adversary who seeks to misuse the storage, processing, or transmittal of data to gain advantage. The misuse is classified as either unauthorized observation of data, unauthorized or improper modification of data, or denial of service. In denial of service misuse, the adversary seeks to prevent someone from using features of the computer system by monopolizing or tying up the necessary resources.
On unitary representations of groups of isometries

Is the topological group of all motions (including translations) of an infinite-dimensional Hilbert space $H$ isomorphic to a subgroup of the unitary group $U(H)$? This question was asked by Su Gao. We answer the question in the affirmative.
On spectroscopic models of the O2 A‐band and their impact upon atmospheric retrievals

[1] Highly accurate spectroscopic models for O2 A-band [b1Σg+ ← X3Σg−(0,0)] absorption are required in numerous satellite- and ground-based remote sensing measurements of atmospheric greenhouse gases. In this study, we quantify the sensitivity of the calculatedA-band transmission spectrum to the choice of line profile and model-input line parameter data. The models considered include the Voigt and Galatry profiles for the individualA-band transitions as well as line mixing and collision-induced absorption. In order of increasing relative importance, we show that measurement uncertainty is influenced by: available line parameter data, Dicke narrowing, line mixing, and collision-induced absorption effects.
Trypanosoma cruzi: exogenously regulated gene expression.

Abstract Wen, L.-M., Xu, P., Benegal, G., Carvaho, M. R. C., Butler, D. R., and Buck, G. A. 2001. Trypanosoma cruzi: Exogenously regulated gene expression. Experimental Parasitology97, 196–204. A regulated expression vector would provide a strong tool for the dissection of gene function in Trypanosoma cruzi. Herein, we establish a system in which genes in T. cruzi expression vectors can be exogenously regulated by tetracycline. We first generated strains of T. cruzi that stably express the repressor of the bacterial tetracycline resistance gene and T7 RNA polymerase. Based on these strains, we developed two T. cruzi expression systems regulated by tetracycline—the first by use of a regulated rRNA promoter and the second by use of a regulated T7 promoter. In the former, we constructed an expression vector in which tetracycline resistance gene operators flank the transcription start point of the T. cruzi rRNA gene promoter. Reporter gene activity from this modified promoter was regulated up to 20-fold in the presence of different concentrations of tetracycline. In the T7 system, tetracycline resistance gene operators flank the transcription start point of the T7 promoter. Reporter gene activity from this modified promoter was regulated up to 150-fold in the presence of different concentrations of tetracycline. Expression in these systems was repressed when tetracycline was removed even after full induction for extended periods in the presence of tetracycline. We are now using these two systems to test protein function in T. cruzi.
EBV-specific memory CD8+ T cell phenotype and function in stable solid organ transplant patients

Immune responses to EBV in immunosuppressed (IS) solid organ transplant (SOTx) recipients have not been well characterized. Here we evaluate the phenotype and function of EBV-specific CD8+ T cells in peripheral blood isolated from "stable" IS SOTx recipients. The EBV-specific CD8+ T cell memory subset distribution in the peripheral blood of patients was examined by flow cytometric analysis using HLA-A2 tetramers incorporating BMLF1 (lytic), and LMP2 and EBNA3A (latent)-derived peptides, in conjunction with mAbs against the CD45RO, CD45RA, and CD62L markers. The ability of CD8+ T cells to produce IFN-gamma in response to the same EBV-derived peptides was measured by ELISPOT assay. Patients and healthy normal donors exhibited similar anti-EBV CD8+ T cell frequencies and specificities against the EBV epitopes evaluated. When compared to healthy normal donors, an overall significant expansion of the CD8+ T cell "effector memory" (CD45RO+/CD62L-) pool, including that of EBV "latent" (LMP2 and EBNA3A)-specific CD8+ T cells was detected in IS SOTx patients. However, the patients' EBV-specific CD8+ T cells showed decreased IFN-gamma production to the EBV-peptide stimulation. These results indicate that the impairment of EBV-specific CD8+ T cell activity is not due to clonal depletion, but is mainly due to impaired functional activation.
Becoming African: Identity formation among liberated slaves in nineteenth-century Sierra Leone1

In an effort to move the acrimonious debates on African identity formation in the Americas in a more fruitful direction this paper places these debated in a larger historiological context and presents a case study of ethnogenesis among Africans who were liberated from the Atlantic slave trade and resettled in the West African colony of Sierra Leone. For these culturally diverse Africans the dynamic processes of creolization and Africanization were generally complementary aspects of personal and communal struggles for survival. Developments among liberated Africans in Sierra Leone offer many richly documented and complex outcomes that might usefully be considered when trying to reconstruct the parallel processes taking place among enslaved Africans in the Americas.
Experimental and theoretical study of spontaneous spin polarization and hysteresis in cesium vapor

We report results of measurements and theoretical modeling of spontaneous spin polarization and associated hysteresis in an optically pumped Cs vapor. We observe hysteresis over the full range (20-450 torr) of N 2 buffer gas pressures tested, and on two hyperfine components of the D I transition, so long as both electronic spin exchange and optical pumping of a resolved ground state hyperfine level take place faster than spin relaxation. On the F = 3 → F e = 4 transition, the spin angular momentum is gained from the linearly polarized pump light, while on the 3 → 3 transition, it comes instead from the buffer gas during collisional quenching. The density-matrix theoretical model we have developed includes the effects of coherence in the excited state. It reproduces all observed features of spontaneous polarization, including hysteresis curves in quantitative agreement with the data across a broad range of experimental parameters.
The structure of scytonemin, an ultraviolet sunscreen pigment from the sheaths of cyanobacteria.

Despite knowledge of the existence of the pigment called scytonemin for over 100 years, its structure has remained unsolved until now. This pigment, the first shown to be an effective, photo-stable ultraviolet shield in prokaryotes, is a novel dimeric molecule (molec. wt. 544) of indolic and phenolic subunits and is known only from the sheaths enclosing the cells of cyanobacteria. It is probable that scytonemin is formed from a condensation of tryptophan-and phenylpropanoid-derived subunits. The linkage between these units is unique among natural products and this novel ring structure is here termed the ‘scytoneman skeleton’. Scytonemin absorbs strongly and broadly in the spectral region 325–425 nm (UV-A-violet-blue, with an in vivo maximum at 370 nm). However, there is also major absorption in the UV-C (λ max=250nm) and UV-B (280–320 nm). The pigment has been recently shown to provide significant protection to cyanobacteria against damage by ultraviolet radiation. The pigment occurs in all phylogenetic lines of sheathed cyanobacteria and possibly represents a UV screening strategy far more ancient than that of plant flavonoids and animal melanins. How diverse organisms deal with UV radiation is considered of vital importance to global ecology.
Models for the strain-rate-dependent behavior of polymer composites

Abstract The present study aims at characterizing the rate-dependent non-linear behavior of two polymeric composite material systems, the unidirectional S2-glass/8553-40 and the woven 7781/Fl55 E-glass fabric in the range of 0.0001 to 1/s under monotonic and proportional loading situations. The objective is to develop a viscoplasticity and a rate-dependent failure model. Uniaxial tension tests were conducted on various off-axis coupon specimens to obtain stress/strain curves for various strain rates. A three-parameter constitutive model is proposed to fit the experimental data. A single rate-dependent parameter is shown to be adequate for capturing the effect of strain rate on strength in both the unidirectional and the woven material systems.
The Generalized Transmission Matrix Stability Criterion

A generalized criterion for stability of a closed tandem connection of double-dinodes is given by the expression A(?) = a 11 +a 22 ?|a|?1 = 0 in which the a 11 are the appropriate terms of the transmission matrix of the tandem net-work prior to closing the loop. If the ?-roots of A(?) have positive real parts, the closing the transmission loop; that is, the network is unstable. The generalized criterion is applicable to transmission loops incorporating bilateral amplifiers, and the transmission loop may be opened wherever desired without con-sideration of the impedances to the left and right of the cut. The criterion is not limited to transmission networks employing amplifiers; like-wise, it applies equally well to electro-mechanical networks or servomechanisms.
Efficiency measurement by data envelopment analysis with econometric applications

A method of estimating the production frontier known as data envelopment analysis (DEA) is applied here through a set of tests to examine its robustness. The empirical application shows that in suitable cases the DEA method proves superior to the ordinary regression method as regards robustness and other measures of sensitivity of parameter estimates.
"The Suppressed Book!": A Previously Unreported Whitman Broadside

Reprints and discusses a broadside published by E. C. Walker in the early 1880s, advertising Leaves of Grass.
Palladium(O) catalyzed coupling reactions in the synthesis of 5-arylpyrimidine nucleosides

Abstract The palladium(O) catalyzed coupling reaction of aryliodides and 3′,5′-di-O-acetyl-5-chloromercuri-2′-deoxyuridine (1) gave 5-aryl substituted 2′-deoxyuridines. Optimum yields were obtained in diglyme at 120° for 3 hours.
Combined Intrinsic and Extrinsic Neuronal Mechanisms Facilitate Bridging Axonal Regeneration One Year after Spinal Cord Injury

Despite advances in promoting axonal regeneration after acute spinal cord injury (SCI), elicitation of bridging axon regeneration after chronic SCI remains a formidable challenge. We report that combinatorial therapies administered 6 weeks, and as long as 15 months, after SCI promote axonal regeneration into and beyond a midcervical lesion site. Provision of peripheral nerve conditioning lesions, grafts of marrow stromal cells, and establishment of NT-3 gradients supports bridging regeneration. Controls receiving partial components of the full combination fail to exhibit bridging. Notably, intraneuronal molecular mechanisms recruited by delayed therapies mirror those of acute injury, including activation of transcriptional activators and regeneration-associated genes. Collectively, these findings provide evidence that regeneration is achievable at unprecedented postinjury time points.
Synthesis and reactivity of bis(imido) uranium(VI) cyclopentadienyl complexes.

The bis(imido) uranium(VI)–C5H5 and –C5Me5 complexes (C5H5)2U(NtBu)2, (C5Me5)2U(NtBu)2, (C5H5)U(NtBu)2(I)(dmpe), and (C5H5)2U(NtBu)2(dmpe) can be synthesized from reactions between U(NtBu)2(I)2(L)x (L = THF, x = 2; L = dmpe, x = 1) and Na(C5R5) (R = H, Me); these complexes represent the first structurally characterized C5H5-compounds of uranium(VI) and they further highlight the differences between UO22+ and the bis(imido) fragment.