cssi/SciSciGPT-SciSciNet huggingface dataset:
Electronic Shell Structure and Metal Clusters

Publisher Summary The chapter presents a study on electronic shell structure and metal clusters. Unlike the “macroscopic” atoms, the metallic clusters described from both experimental and theoretical viewpoints in this chapter come far closer to having bulk properties, because they are 10–100 times bigger. The science of clusters is a rapidly growing interdisciplinary field with great promise for the production of new ideas and physical systems. Its ideas are relevant to related problems in the physics of atoms, molecules, condensed matter, and transitions among these systems. The chapter presents a review emphasizing on the electronic shell model, which is elegant and simple, avoids the complexity of elaborate quantum chemical computer calculations for clusters containing large numbers of atoms, and possesses the power of predictability. The study of the physical properties of states intermediate between the atom and the solid is called cluster physics. Lacking a precise definition, it is said that a cluster is a stable group of a few or a few hundred identical atoms or molecules. This chapter mainly discusses metal clusters. Atomic theory depends on the application of angular momentum conditions in the Coulomb field.
Genetics: Ancient DNA Clarifies Population Histories of the Northeastern Margin of North America.

A new study of ancient mitochondrial DNA from Newfoundland and Labrador indicates that this region at the northeastern margin of North America was populated three times in succession by different indigenous groups. This research helps shed light on the movement of populations across the continent, following the initial peopling of the Americas.
Flat extension and ideal projection

Abstract A generalization of the flat extension theorems of Curto and Fialkow and Laurent and Mourrain is obtained by seeing the problem as one of ideal projection.
Biochemical Studies on the Putative Nitroso Metabolite of Chloramphenicol: A New Model for the Cause of Aplastic Anemia

Chloramphenicol (CAP) is one of the oldest and more potent broad spectrum antibiotics available for the treatment of certain severe infections. CAP is an unusual natural product since it possesses both the nitro functional group and C-Cl bonds, neither of which are particularly common among terrestrial natural products. The necessity of the nitro functional group to the antimicrobial action of CAP has been thoroughly studied (reviewed in ref. 1). Unfortunately, the clinical use of CAP often causes toxic reactions, most notably to the hemopoietic system (2). The most serious of these actions is the rare, but generally fatal condition of aplastic anemia (hypoplastic marrow failure). In 1980 Tunis made the hypothesis that reduced intermediates (nitroso, hydroxylamine) of the nitro group of CAP were responsible for the aplastic anemia associated with CAP (2); however, this hypothesis had actually been proposed by the Weisburgers in 1967 (3). It was the Weisburgers’ hypothesis that prompted us to synthesize CAP-NO, CAP-NHOH and related analogs in 1978 (1), and to investigate the potential toxicity of such putative metabolites to hemopoietic precursor cells (4,5).
Estimation of Modulation Index for Partial Response CPM Signal

Continuous phase modulation (CPM) is a power and bandwidth efficient modulation scheme used in cellular, personal, and satellite communications among other applications. If the modulation index of the CPM waveform used by the transmitter is unavailable at the receiver, serious performance degradation may occur. This paper investigates the problem of modulation index estimation for partial response continuous phase modulation schemes. Specifically, we propose two novel estimators for the CPM signal observed in an additive white Gaussian noise channel. A non-data aided method of moments (MoM) estimator based upon the fourth-order cumulants and a data-aided best linear unbiased estimator (BLUE) based upon an approximate linear phase model of the received CPM signal have been proposed. Modified Cramer–Rao lower bound is derived for the partial response CPM schemes to assess the performance of the estimators. We also perform numerical simulations to compare the mean-squared error (MSE) performance of the proposed MoM and BLUE estimators with previously proposed estimators in the literature. It is shown that the MoM estimator exhibits good MSE performance at low signal-to-noise ratio (SNR) while the BLUE estimator performs very well at high SNRs. Moreover, the proposed estimators have lower complexity than existing methods and are based upon non-iterative algorithms.
RISK OF LEAD DISLODGEMENT WITH CATHETER ABLATION IN PATIENTS WITH RECENTLY IMPLANTED CARDIAC IMPLANTABLE ELECTRONIC DEVICE: A FIVE-YEAR EXPERIENCE

Patients with cardiac implantable electronic devices (CIEDs) frequently have arrhythmias warranting catheter ablation (CA). The risk of lead dislodgement with CA in patients with CIED implant within 1 year is uncertain. We retrospectively evaluated patients undergoing CA of arrhythmias at an
Techniques of Endovascular Mesenteric Revascularization

The most common cause of chronic mesenteric ischemia (CMI) is atherosclerotic disease, accounting for over 90 % of cases in most series. Atherosclerotic lesions usually affect the origin or the proximal 2–3 cm of the mesenteric arteries, frequently with associated plaque in the aorta and renal arteries. Because of the extensive collateral network, the majority of patients with symptoms of CMI have significant stenosis or occlusion of at least two of the three mesenteric arteries. However, contrary to what has been propagated in many surgical textbooks, this is not an absolute requirement. The clinical significance of ischemia correlates not only to the extent of disease but also the adequacy of collateral pathways, acuteness of symptoms, and presence of arterial steal; approximately 2–10 % of patients with CMI have single-vessel disease, which affects primarily the SMA and patients with poorly developed collaterals or more acute presentation, as might be predicted from the postprandial hyperemic response.
The Singular Sturm-Liouville Problem

The Sturm-Liouville problem is singular when the results of Chapter IX are not applicable. This may happen when the coefficients, p, q or w become infinite, when p or w approaches 0 at α or β, or when the interval [α,β] is infinite in length.
Three essays on green supply chain management

The dissertation includes three essays. These three empirical studies apply structural equation modeling (SEM) to examine key issues in green supply chain management. The hypothesized model is tested using a sample of supply chain managers derived from a Dun and Bradstreet database. The data collection is through a large webbased survey. The first essay examines how a firm’s proactive environmental management strategy influences operational performance. The second essay examines the effect of how top management responds to pressure from a firm’s rivals and stakeholders to implement green supply management practices. The last essay examines how environmental management competitive pressure from main competitors influences a firm to pursue and produce new environmental innovations into the marketplace (e.g., focal firm’s green success) through its green supply chain integration activities.
The chronic infusion of hexamethonium and phenylephrine to effectively clamp sympathetic vasomotor tone. A novel approach.

Abstract There are several ways to assess the sympathetic nervous system (i.e., nerve recording, sympathectomy, etc.), each of which has its own limitations. The present study was conducted to establish a standard, testable chronic ganglionic blockade protocol with a fixed level of adrenergic vasomotor tone. Rats were instrumented with radio telemetry pressure transducers and venous catheters for continuous measurement of arterial pressure and infusion of pharmacologic agents, respectively. After 3 days of control measurements, rats were infused for 9 days with a continuous dose of the ganglionic blocking agent, hexamethonium and the alpha-adrenergic agonist, phenylephrine. In this way, sympathetic tone was effectively “clamped,” which maintained a normal level of arterial pressure. Control pressure between hexamethonium + phenylephrine (HEX + PE) treated rats (101 ± 2 mmHg) and saline (VEHICLE) treated rats (101 ± 2 mmHg) was not different. By day 9 of the infusion, there was no difference in arterial pressure between groups (VEHICLE: 101 ± 3 mmHg, HEX + PE: 103 ± 3 mmHg) or from the control period, although heart rate was significantly less in HEX + PE rats (VEHICLE: 406 ± 9 beats/min vs. HEX + PE: 343 ± 6 beats/min). The effectiveness of this technique was validated by measuring cardiac baroreceptor reflex sensitivity, as well as the pressor response to the direct ganglionic stimulating agent, 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP). Compared to VEHICLE rats, HEX + PE rats showed no tachycardic response to depressor stimuli and an absence of a pressor response to DMPP. We conclude that this protocol is a useful technique to chronically, yet reversibly, block the sympathetic nervous system in experimental settings.
Post-malaria neurological syndrome: a rare neurological complication of malaria

Post-malaria neurological syndrome (PMNS) is a rare self-limiting neurological complication that can occur after recovery from malaria, usually severe falciparum malaria. It is characterized by a myriad of neuropsychiatric manifestations including mild neurological deficit to severe encephalopathy. PMNS was first described in 1996 and since then there have been 48 cases reported in the English literature. We report another case of PMNS in a 24-year-old healthy male and present a review of the disease entity. We searched PMNS-related journal articles and case reports in the English literature, using PubMed and Google search engines. A total of forty-nine cases meeting the diagnostic criteria of PMNS were selected in this review. PMNS is a rare complication of severe malaria that might be underreported. It can develop up to 2 months after clearance of parasitemia. Clinical features can be variable. Most cases are self-limited, but more severe cases may benefit from steroid therapy.
Managing Satellite Debris in Low-Earth Orbit: Incentivizing Ex Ante Satellite Quality and Ex Post Take-Back Programs

Increased economic activity in low-Earth orbit (LEO) in the past century created debris fields that impede current and future economic activities. We propose an economic model that combines elements of patent law with space law to enable comparisons of policy instruments. In particular, we propose policies that leverage the intellectual property rights system and that facilitate additional joint research and development to incentivize ex ante increases in satellite quality. Our model also considers the impact of individual and collective ex post LEO debris take-back programs, analogous to those designed for terrestrial contexts. Our results suggest policy refinements for the outer space context that may be of interest beyond managing satellite debris in LEO.
Experimental Investigation of Bioenergy Production from Small-Scale Gasification of Landfill-Diverted Wood Wastes

Small-scale biomass gasification systems integrated with internal combustion engines can be a solution to the dual challenges of reducing greenhouse gas emissions from electricity production and reducing waste sent to landfills; however, these systems are typically designed for high-value, virgin wood chip feedstocks. This investigation aims to improve the feasibility of this technology by exploring the use of landfill diverted wood wastes (construction and demolition waste, used pallets and oriented strand board) in place of costly wood chips for the production of bioenergy in a pilot scale gasifier combined with an internal combustion engine generator operating at 10 kWe. The effect of feedstock bulk properties on gasifier operational stability and process parameters, including magnitude and variability of temperature and pressure drop, are investigated. Low bulk density ( 55°) increased system instability through the formation and collapse of bridges and channels in the gasifier. Tar and particulate matter in the producer gas are quantified, as well as removal efficiencies of the gas clean-up for different feedstocks. Tar concentration in the syngas was in the range of 1.2 to 5.2 g/m3 downstream of gas clean-up, and was found to increase with system instability parameters and feedstock moisture. Finally, over the range of feedstocks examined in this study, a novel empirical correlation was developed to describe tar production from the gasifier as a function of feedstock bulk properties. The relationship between feedstock bulk properties and tar production is a unique finding and can enable to development of reliable waste-to-energy gasification systems.
The Case for State Borrowing as a Response to the Current Crises

This essay explains how and why U.S. state governments can and should borrow funds in the absence of sufficient federal aid during the COVID-19 pandemic.
Assessing rectal cancer treatment response using photoacoustic microscopy: deep learning CNN outperforms supervised machine learning model

Rectal adenocarcinoma is a common cancer in the United States. Current standard of care techniques (colonoscopy and MRI) have notable drawbacks and surgeons have aggressively put most patients into surgical intervention. Here we have developed a new handheld co-registered ultrasound and acoustic-resolution photoacoustic endoscope (AR-PAE) to evaluate rectal cancer in vivo. The PAE - convolutional neuron network (PAE-CNN) models were trained, validated, and tested. Hyperparameters of PAE-CNN including convolutional kernel size, max pooling kernel size, convolution layers and fully connected layers which connect to amount of imaging information preserved were carefully tuned to optimize classification performance.
Functional compartmentalization of photoreceptor neurons

Retinal photoreceptors are neurons that convert dynamically changing patterns of light into electrical signals that are processed by retinal interneurons and ultimately transmitted to vision centers in the brain. They represent the essential first step in seeing without which the remainder of the visual system is rendered moot. To support this role, the major functions of photoreceptors are segregated into three main specialized compartments—the outer segment, the inner segment, and the pre-synaptic terminal. This compartmentalization is crucial for photoreceptor function—disruption leads to devastating blinding diseases for which therapies remain elusive. In this review, we examine the current understanding of the molecular and physical mechanisms underlying photoreceptor functional compartmentalization and highlight areas where significant knowledge gaps remain.
The structure of cultural experience

Abstract The theories of William James and John Dewey regarding the nature of experience suggest that there is an aspect of the organization of culture that sociologists have not yet studied formally, namely the structuring of sensory experience. We propose a way of trying to measure respondents’ experience of “textural” music, as opposed to their preferences, evaluative judgments, or associations. We employ a novel data-gathering approach as part of 61 in-depth interviews, and then analyze the dimensionality of the distribution of reported experiences. We find three dimensions, all of which seem to touch upon fundamentally meaningful binaries of embodied experience.
Combining computer-mediated communication with data-driven instruction: EFL learners’ pragmatic development of compliment responses

Abstract The use of computer-mediated communication (CMC) combined with data-driven instruction to facilitate second/foreign language (L2) pragmatic development has been shown to be promising. Despite increasing amounts of CMC-based interventional studies of L2 pragmatics, existing literature is inconclusive concerning the influence of CMC paired with data-driven instruction on L2 pragmatic competence. Moreover, few studies have incorporated qualitative analyses exploring factors that affect L2 learners' pragmatic decision-making. Thus, this mixed-methods study aimed to further investigate the effect of CMC on English as a Foreign Language (EFL) learners’ pragmatic development of compliment responses (CRs) in two conditions: CMC by itself and CMC combined with data-driven instruction. Fifty-nine university-level Chinese EFL students were divided into two groups; the experimental group engaged in CMC with native speakers and received data-driven instruction in CRs, whereas the control group had CMC without data-driven instruction. Results revealed that the experimental group outperformed the control group in the immediate and delayed post-intervention tests regarding appropriateness and variety, indicating a positive and durable effect of CMC coupled with data-driven instruction on L2 pragmatic development. Additionally, findings from retrospective interviews showed that L2 pragmatic knowledge, crosslinguistic influence, and online processing load potentially influence L2 pragmatic choices. Implications for instructors are discussed.
Management of Locally Advanced Adenocarcinoma of the Esophagus and Gastroesophageal Junction: Finally a Consensus

Opinion statement: Adenocarcinoma of the esophagus is increasing in incidence in Western nations leading to increased interest in and opportunity to study optimal management. Randomized trials have now robustly demonstrated the preoperative therapy with chemoradiotherapy and chemotherapy alone improves survival outcome for the bulk of curable patients, those with locally advanced T1N1M0 and T2-3 N0-1 M0 disease. Evidence suggests but does not confirm that radiation-containing regimens are more beneficial. Clinical staging is designed to exclude patients with T1N0M0 disease who may be treated with surgery alone and those with metastatic disease who may not benefit from intensive local therapy. The approach to clinical staging includes endoscopy with ultrasound and fine needle aspirate to assess local and regional disease, supplemented by CT and PET scanning primarily to exclude metastatic disease. Minimally invasive approaches to esophagectomy may be used with the goal of reducing complications, but there is no evidence that mortality or ultimate outcome is improved.
Molecular cloning of the Clostridium botulinum structural gene encoding the type B neurotoxin and determination of its entire nucleotide sequence.

Abstract DNA fragments derived from the Clostridium botulinum type A neurotoxin (BoNT/A) gene (botA) were used in DNA-DNA hybridization reactions to derive a restriction map of the region of the C. botulinum type B strain Danish chromosome encoding botB. As the one probe encoded part of the BoNT/A heavy (H) chain and the other encoded part of the light (L) chain, the position and orientation of botB relative to this map were established. The temperature at which hybridization occurred indicated that a higher degree of DNA homology occurred between the two genes in the H-chain-encoding region. By using the derived restriction map data, a 2.1-kb BglII-XbaI fragment encoding the entire BoNT/B L chain and 108 amino acids of the H chain was cloned and characterized by nucleotide sequencing. A contiguous 1.8-kb XbaI fragment encoding a further 623 amino acids of the H chain was also cloned. The 3' end of the gene was obtained by cloning a 1.6-kb fragment amplified from genomic DNA by inverse polymerase chain reaction. Translation of the nucleotide sequence derived from all three clones demonstrated that BoNT/B was composed of 1,291 amino acids. Comparative alignment of its sequence with all currently characterized BoNTs (A, C, D, and E) and tetanus toxin (TeTx) showed that a wide variation in percent homology occurred dependent on which component of the dichain was compared. Thus, the L chain of BoNT/B exhibits the greatest degree of homology (50% identity) with the TeTx L chain, whereas its H chain is most homologous (48% identity) with the BoNT/A H chain. Overall, the six neurotoxins were shown to be composed of highly conserved amino acid domains interceded with amino acid tracts exhibiting little overall similarity. In total, 68 amino acids of an average of 442 are absolutely conserved between L chains and 110 of 845 amino acids are conserved between H chains. Conservation of Trp residues (one in the L chain and nine in the H chain) was particularly striking. The most divergent region corresponds to the extreme carboxy terminus of each toxin, which may reflect differences in specificity of binding to neurone acceptor sites.
Business Turnaround Processes Following Acquisitions: Reconsidering the Role of Retrenchment

Abstract For almost two decades, a prevailing view has been that business turnaround processes should match the strategic or operating nature of the underlying problems. Based on their study of textile firms (Robbins and Pearce, 1992) , Pearce and Robbins (1993) questioned this view, offering a model that suggests that retrenchment is a desirable initial response, regardless of the types of problems faced. This article describes a test of the Pearce/Robbins view that examined the value of retrenchment following the acquisition of 46 distressed firms. The present study, thus, extended the Pearce/Robbins findings and conclusions beyond the independent business focus of their own work to the postacquisition context. An empirical study of 46 distressed and recently acquired firms revealed no retrenchment effects of performance ( p = 0.7027), although two other types of actions: (1) capital infusion; and (2) integration, did influence performance ( p = 0.0198 and p = 0.0860, respectively). A negative interaction of degree of decline and capital infusion on performance was found also ( p = 0.0564). The implications of these findings are discussed. Because no significant retrenchment effect was found, this raises questions about the generalizability of the Pearce/Robbins conclusions. Specifically, this study showed that retrenchment may not be a universally desirable stage in the business turnaround process because retrenchment did not seem beneficial following the acquisition of distressed firms. Therefore, this study identified a potential bound to the generalizability of the conclusions resulting from the Robbins and Pearce (1992) study. Although their conclusions may be valid for independent businesses, they may not apply to businesses recently acquired by other firms. A primary implication, therefore, is that the desirability of particular turnaround actions or processes may vary from one context to another. Furthermore, the present study found that, in the postacquisition context, efforts by corporate parents to facilitate turnaround by infusing capital into the distressed firms actually resulted in worse performance. In contrast, efforts to integrate distressed firm assets into other businesses within the parents' corporate portfolios proved to be beneficial.
Methane utilization by oxidative coupling: I. A study of reactions in the gas phase during the cofeeding of methane and oxygen

Abstract The oxidative coupling of methane has been investigated in the absence of catalysts by cofeeding methane and oxygen. A survey on the effects of varying several operating conditions shows that under certain conditions significant gas-phase oxidative coupling can occur in the absence of catalysts. The reaction products were C 2 H 6 , C 2 H 4 , C 3 H 8 , C 3 H 6 , CO (the main oxidation product), CO 2 , H 2 , H 2 O, and traces of HCHO and C 4 and C 5 hydrocarbons when conversions were high. The general trend dictated by the gas-phase kinetics is that the hydrocarbon product selectivity falls as the conversion increases. Specifically, at methane conversions of 2%, the hydrocarbon product selectivity was around 65%, but when methane conversions were increased to 32%, the hydrocarbon selectivity decreased to 29%. The apparent activation energy for methane conversion in the gas phase was found to be around 55 kcal/mole which is similar to that reported for the gas-phase reaction of methane and molecular oxygen forming methyl and hydroperoxy radicals. Several gas-phase results have been presented for comparative purposes with catalytic oxidative coupling studies. A reaction pathway for the gas-phase oxidative coupling network has been considered and compared to proposed catalytic reaction pathways. The implications that the observed results might have on catalytic oxidative coupling of methane have also been considered.
LIRS, SIRS, Sepsis, MODS and Tertiary Peritonitis

In the first chapter of this book, we talk about your patient being locally and systemically inflamed by his surgical disease, your treatment, and the complications of both. In almost every subsequent chapter, you have been reminded that the magnitude of the inflammation correlates with that of the disease process and the operation. You were told that the more inflammation there is—or that you create—the more likely is your patient to develop organ dysfunction or failure and to die. In this chapter, we concentrate on the inflammation—both local and systemic—and its consequences. The biological events involved are immense and chaotic, but let us maintain a simplistic attitude—you did not buy this book to read about cytokines, right?
State Feedback Stabilization of Nonlinear Systems via the Neural Network Approach

We consider the state feedback stabilization of autonomous nonlinear systems described by dx/dt = Ax + Bu - f(x), where f(x) is a memoryless nonlinearity and does not necessarily satisfy the sector conditions. Classical results can not be used to infer stability of the closed loop system. By using neural network techniques, however, we find a state feedback gain matrix that ensures the asymptotic stabilit for any specified equilibrium.
Human Body Model, Machine Model, and Charge Device Model ESD testing of surface micromachined microelectromechanical systems (MEMS)

Electrostatic discharge (ESD) and electrical overstress (EOS) damage of surface micromachined Microelectromechanical Systems (MEMS) were identified as new and harmful failure modes. This failure mode was not addressed previously due to either the proprietary nature of the device or the close resemblance to stiction, another dominant failure mechanism in MEMS. This paper addresses ESD failure mechanisms in MEMS resulting from testing using the Human Body Model (HBM), Machine Model (MM), and Charge Device Model (CDM). Three types of devices were tested to evaluate the effects of spring stiffness and comb finger (actuator) geometry on ESD susceptibility.
Reconstructing annual area burned in the northern Rockies, USA: AD 1626–2008

We used a tree-ring chronology as a proxy for annual area burned (AAB) in the northern Rockies, USA during AD 1626–2008. We correlated annual ring widths of alpine larch trees (Larex lyallii) sampled at a single high-elevation site in western Montana with AAB for the United States Forest Region 1. Radial growth was significantly associated with AAB (R2 = 0.35, p < 0.001), demonstrating the potential to use high-elevation conifers as markers of interannual variations in fire activity. The results suggest that the period 1929–1945 would have been the most active since the early 1600s had not extensive fire suppression and harvest activities altered the fire regime. Comparisons of the predicted values of area burned to a century-long fire atlas were significant for both the entire record (rs = 0.333, p < 0.01) and reconstruction period (rs = 0.645 p < 0.001). Similarly, predicted AAB was significantly correlated (r = 0.230) to fire-scar data during 1650–1900. These results suggest the feasibility of using tree-ring chronologies as an additional measure of fire activity, particularly as they allow an assessment and comparison of fire activity during centuries with and without fire suppression and harvest activities.
Diagnosis and Staging of Medication-Related Osteonecrosis of the Jaw

The relationship between osteonecrosis of the jaw and bisphosphonate therapy was initially established more than 10 years ago. Since that time our understanding of this disease process has evolved as the direct result of clinical, basic science, and animal research initiatives. Medication-related osteonecrosis of the jaw (MRONJ) is a well-known entity now known to be associated with various antiresorptive therapies and recently with antiangiogenic medications. This article reviews the recently modified diagnostic criteria for MRONJ with a focus on the clinical, histopathologic, and imaging characteristics of this disease process.
Clinical engineering: educational aspects

The responsibilities of clinical engineers are delineated. The development of graduate programs for clinical engineers is then discussed. Three aspects of such a program are stressed: (1) individuals interested in clinical engineering must have sufficient background in a particular engineering discipline; (2) it is an interdisciplinary activity and requires sufficient background in human physiology and the biological sciences; and (3) the academic component of any graduate clinical engineering program should be accompanied by an internship experience within the hospital/medical center environment. >
The Julia sets of quadratic Cremer polynomials

Abstract We study the topology of the Julia set of a quadratic Cremer polynomial P . Our main tool is the following topological result. Let f : U → U be a homeomorphism of a plane domain U and let T ⊂ U be a non-degenerate invariant non-separating continuum. If T contains a topologically repelling fixed point x with an invariant external ray landing at x , then T contains a non-repelling fixed point. Given P , two angles θ , γ are K-equivalent if for some angles x 0 = θ , … , x n = γ the impressions of x i − 1 and x i are non-disjoint, 1 ⩽ i ⩽ n ; a class of K -equivalence is called a K-class . We prove that the following facts are equivalent: (1) there is an impression not containing the Cremer point; (2) there is a degenerate impression; (3) there is a full Lebesgue measure dense G δ -set of angles each of which is a K -class and has a degenerate impression; (4) there exists a point at which the Julia set is connected im kleinen; (5) not all angles are K -equivalent.
Structure and properties of iron containing glassy carbons

Abstract Glassy carbons containing iron were prepared from copolymers of furfuryl alcohol and ferrocene derivatives at heat-treatment temperatures from 500°C to 2500°C. The copolymerization produced a highly dispersed state of iron in carbonaceous matrices at least in the early stage of pyrolysis. Above 500°C, the homogeneously dispersed iron separated into irregularly spaced domains consisting of cementite, pure iron and iron compounds of unknown composition. Addition of iron resulted in a local graphitization of the glassy carbon at heat-treatment temperatures above 1000°C. At heat-treatment temperatures between 500°C and 800°C, electrical resistivities of the iron-doped carbons were much smaller than those of unmodified polyfurfuryl alcohol carbons but followed more or less the behavior of the latter for heat-treatment temperatures above 800°C.Measurements of mechanical properties indicated a remarkable increase in tensile strength of the low temperature carbons (500°C) with increasing iron content but the strength of the iron containing carbons decreased at higher carbonization temperatures.
Apoptosis induced by cisplatin nephrotoxic injury

Apoptosis induced by cisplatin nephrotoxic injury. An agent often used in cancer treatment, cisplatin may cause acute renal failure after even a single dose. Recent laboratory studies confirmed the induction of renal cell apoptosis by cisplatin. Reduction in cell viability as well as increase in the number of cells with fragmented nuclei correlated with cisplatin exposure in a dose-dependent manner. Gel electrophoresis revealed the presence of a characteristic laddering pattern which was preceded by an increase in caspase-3 activity. As the cisplatin concentration increased beyond 50 μm, the elevation of caspase-3 activity declined, which suggests that necrosis, instead of apoptosis, is more likely to be responsible for cell death secondary to higher cisplatin concentrations. Elucidation of the molecular mechanisms of cisplatin nephrotoxicity may lead to the development of a novel therapeutic strategy that targets cancer cell death while simultaneously minimizing renal injury.
Uridine Uptake by Rat Uterus. Influence of Injection Route

During a 10 min labeling period the uterus of the rat accumulates up to 10 × more 3H-uridine when this tracer is injected ip than when it is given sc. Incorporation into the RNA is enhanced by ip administration to an even greater extent than is total uptake. Intraperitoneal administration also greatly increases the variability of tracer uptake by the uterus. Tritium is distributed uniformly in different segments of the uterus after sc injections but is unequally distributed when ip injections are made. Aiming the needle toward one horn of the uterus when giving an ip injection clearly biases tracer distribution on the uterus. When plasma tritium is examined much less radioactivity is associated with uridine 10 min after an ip injection than after a sc injection. The converse is true of the acid-soluble fraction of the uterus (much less tritium is associated with uridine or UMP when the isotope was injected sc). Simultaneous studies with 14C-inulin and 3H-uridine indicate that much of the uridine given by ...
Analysis for lysine, arginine, histidine, and tyrosine in biological fluids.

Abstract A method for the analysis of lysine using a specific decarboxylase has been developed. The amine resulting from decarboxylation is reacted with dinitrofluorobenzene. The product is selectively extracted into chloroform and determined by spectrophotometry at 400 mμ. The sensitivity of the method is at least one hundred times greater than manometric assay using the same enzyme. Lysine in blood plasma and urine may be easily measured at physiological levels. The method has been extended to tyrosine, arginine, and histidine, and data are presented for its extension to the amine analogs of several other amino acids.
Microtitration of weak organic acids in nonaqueous solvents

The applicability of nonaqueous titrimetry to the microdetermination of weak organic acids has been established.
Threads™: how to restructure a computer science curriculum for a flat world

In his book The World is Flat, Thomas Friedman convincingly explains the challenges of a global marketplace [4]. One implication is that software development can be out-sourced, as can any narrow, skills-based occupation; however, as Friedman also points out, leadership, innovation, and insight are always in demand. We have recently created and are implementing threadstm, a new structuring principle for computing curricula. Threads provides one clear path for computer scientists seeking to reinvent and re-invigorate computer science degree programs. Threads form a cohesive, coordinated set of contexts for understanding computing. The union of all threads covers the breadth "computer science." The union of any two threads is sufficient to cover a computer science degree. In this paper, we describe Threads, our process, the impact so far, and some of our future plans. We close with recommendations for other schools, especially schools with smaller programs.
The immune status of the myelin deficient rat and its immune responses to transplanted allogeneic glial cells.

Abstract This study examined the immunological responsiveness of the myelin deficient ( md ) rat, and its immune response to transplanted allogeneic glial cells, with and without immunosuppression therapy. Skin grafts from an ACI strain of rat were found to be acutely rejected by Wistar md rats. Anti-donor cytotoxic antibody was produced and alloreactive T helper cells were expanded in these mutants after skin sensitization. Equivalent high frequencies of precursor cytotoxic T lymphocytes (pCTLs) specific to the ACI MHC antigens were observed in both normal controls and mutants. An immune response was noted when allogeneic glial cells were transplanted into the spinal cords of md rats, which was effectively suppressed for 2 weeks post transplantation by treatment with either cyclosporin A (CsA) or a monoclonal antibody to the interleukin-2 receptor (IL-2R). These results demonstrate that md rats are immunocompetent, but that CNS allograft rejection can be prevented by immunosuppressive agents.
A note on job matching with budget constraints

Abstract Recent papers have obtained results for two-sided matching games in which agents may have complex preferences. This note observes that these results depend on the assumption that firms do not face budget constraints.
Zn/Fe systematics in mafic and ultramafic systems: Implications for detecting major element heterogeneities in the Earth’s mantle

Abstract Oceanic basalts, such as mid-ocean ridge basalts (MORB) and ocean island basalts (OIB), are characterized by large isotopic and trace element variability that is hard to reconcile with partial melting of a peridotitic mantle alone. Their variability has been attributed to the presence of heterogeneities within the mantle, such as recycled crust, metasomatized material or outer core contribution. There have been few attempts to constrain the major element composition of those heterogeneities, most studies focusing on incompatible trace elements and radiogenic isotopes. Here, we report Zn, Mn and Fe systematics in mafic and ultramafic systems (whole-rocks and minerals) and we explore their use for detecting lithological heterogeneities that deviate from peridotitic mantle dominated by olivine and orthopyroxene. We suggest that Zn/Fe ratio is a particularly promising proxy. Zn/Fe fractionates equally between olivine, orthopyroxene and melt (e.g. the inter-mineral exchange coefficients K D ( Ol / melt ) Zn / Fe ∼ K D ( Opx / melt ) Zn / Fe is ∼0.9–1), and the distribution of Zn/Fe between minerals appears to be temperature-independent within error. In contrast, clinopyroxene and garnet are characterized by low Zn/Fe ratios compared to co-existing melt, olivine and orthopyroxene, that is, K D ( Cpx / melt ) Zn / Fe and K D ( Gt / melt ) Zn / Fe are both K D ( rock / melt ) Zn / Fe
Thermodynamic Origin of Prolyl Peptide Bond Isomers

The thermodynamic preference for the trans isomer of prolyl peptide bonds arises almost entirely from enthalpy in aqueous buffer and in toluene.
Temperature and composition dependence of the strength of aluminum base zinc alloy single crystals

Abstract The critical resolved shear stress, σc, of zone-hardened aluminum base zinc alloys was found to increase with ( c Zn ) 1 2 at room temperature, suggesting that the stress necessary to shear the zones is larger than that necessary to overcome the Mott-Nabarro misfit stresses. On cooling to 4.2°K, σc of a particular alloy (e.g. 5.3 at.% Zn) increases considerably more than predicted. This is attributed in part to offcenter cutting of zones and in part to cutting of mismatch dislocations presumed to be located in the region between the core of the zone and the depleted shell. σc, of zone-hardened Al-6 at. % Ag was also measured to 4.2°K. The increase in σc is considerably less in this case, presumably because the atomic sizes of aluminum and silver are nearly the same; misfit dislocations are not expected in this case. The supersaturated solid solution (reverted) state of the Al-Zn alloys was also studied. The percentage increase in σc on cooling is considerably greater than in the zone-hardened alloys. This is attributed to the presence of clusters in the solid solution.
Abstract 2486: African ancestry is associated with high-risk disease and event-free survival in children with neuroblastoma

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Background In a cohort of 3539 children with neuroblastoma, we have previously reported that self-reported black race is significantly associated with high-risk disease (p 5% total SNPs interrogated without a genotype call) and 390 patients with missing clinical data. Genotypes from the remaining 2790 patients were included in the analysis. Using SNPs common to each of the genotyping platforms, ancestral reference populations from the International HapMap Project (Caucasian - CEU, African - YRI and Asian - CHB/JPT) and the EIGENSTRAT method, a principal components analysis was performed and an ancestry map of all patients was created. Principal Component 1 (PC1), which separated black neuroblastoma patients and the YRI HapMap samples from all other ethnic groups, was tested as a continuous variable in a Cox Proportional Hazard Regression model of event-free survival (EFS) and in an ordinal logistic regression of risk group. Using a k-means clustering algorithm, patients were grouped into 1 of 5 ethnic clusters;EFS of clusters was compared using a log-rank test, and Kaplan-Meier curves were plotted. Results PC1 was correlated with neuroblastoma risk group classification (p=0.0063). PC1 was also correlated with EFS (p=0.044). Compared to Caucasian patients, patients with African ancestry had the poorest EFS (log rank p = 0.0257). Discussion Here we show that the component of genomic variation that co-segregates with African ancestry is associated with high-risk disease and event-free survival. Patients with African ancestry had inferior outcomes to patients of Caucasian ancestry. We hypothesize that germline genetic variants associated with both the development of high-risk neuroblastoma and event-free survival after chemotherapy will have different allelic frequencies in Caucasian and African populations and that patients of African ancestry may also harbor unique genetic variants associated with high-risk disease and event-free survival not found in Caucasian patients. Efforts to identify these genetic variants are underway. These results underscore the need to perform association studies from a variety of ancestries, as each group may yield novel associations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2486. doi:1538-7445.AM2012-2486
A kinetic threshold between negative and positive selection based on the longevity of the T cell receptor-ligand complex.

We have developed a unique in vivo system to determine the relationship between endogenous altered peptide ligands and the development of major histocompatibility complex class II– restricted T cells. Our studies use the 3.L2 T cell receptor (TCR) transgenic mouse, in which T cells are specific for Hb(64–76)/I-Ek and positively selected on I-Ek plus self-peptides. To this endogenous peptide repertoire, we have individually added one of six well-characterized 3.L2 ligands. This transgenic approach expands rather than constrains the repertoire of self-peptides. We find that a broad range of ligands produce negative selection of thymocytes in vivo. When compared with the in vitro TCR–ligand binding kinetics, we find that these negatively selecting ligands all have a half-life of 2 s or greater. Additionally, one of two ligands examined with no detectable binding to the 3.L2 TCR and no activity on mature 3.L2 T cells (Q72) enhances the positive selection of transgenic thymocytes in vivo. Together, these data establish a kinetic threshold between negative and positive selection based on the longevity of TCR–ligand complexes.
Cell cycle regulation of the double stranded RNA activated protein kinase, PKR

The interferon (IFN)-induced, double stranded RNA (dsRNA)-activated serine/threonine kinase, PKR, is a potent negative regulator of cell growth when overexpressed in yeast or mammalian cells. To determine whether endogenous PKR plays a role in cell growth control, we have investigated the regulation of PKR levels and activity during the cell cycle in human glioblastoma T98G cells. The steady-state level of PKR mRNA in T98G cells was highest in growth arrested cells, dropped sharply within 3 h of serum stimulation then gradually increased as cells progressed through G1, reaching a plateau in early S phase. PKR protein level increased following serum stimulation reaching a peak at the G2+M boundary and declining thereafter. In contrast, PKR kinase activity exhibited two peaks, in early G1 and at the G1/S boundary, declining sharply in early S phase. Thus, the activity profile did not follow the protein profile indicating a tight regulation of PKR at the level of activity. In T98G cells expressing the catalytically inactive PKRK296R the dsRNA-induced activation of NF-kappaB and IRF-1 was suppressed and the mutant cells exhibited resistance to stress induced apoptosis. Cell cycle distribution analysis showed that the mutant expressing cells exhibited longer G1 phase and fewer cells engaged in S phase. Furthermore, early passage mouse embryo fibroblasts derived from PKR knockout mice grew more slowly compared with the control cells. Taken together these results suggest that PKR may play a role in cell cycle progression.
The behavior of the venous pressure during various stages of chronic congestive heart failure

Abstract 1. 1. Daily determinations of weight and venous pressure were made during thirty-four significant changes in the stage of chronic congestive heart failure in twenty-three patients. This included twenty-six instances of recovery and eight of decompensation. 2. 2. In general, the venous pressure and the weight varied concordantly. In some patients, either weight or venous pressure began changing prior to the other. 3. 3. The findings indicate that it is not established that an elevation in either weight or venous pressure need precede the other in the development of the syndrome of chronic congestive heart failure, and that depending on the condition of the tissues, either of the two might evidence a clinically detectable rise prior to the other. 4. 4. The behavior of the venous pressure in the patients studied confirms the value of this procedure in the diagnosis and proper clinical evaluation of congestive heart failure, especially when serial determinations are made. 5. 5. The dependence, in part at least, of the venous pressure on the condition of the tissues is demonstrated.
Percutaneous absorption and dermal delivery of cyclosporin A

The present study deals with attempts to deliver cyclosporin A into the deeper skin and some of the fundamental reasons why this proves so difficult. Because of different physicochemical requirements for the solution and activity of cyclosporin A and the enhancer, n-decylmethyl sulfoxide, it was hard to demonstrate increases in permeation of cyclosporin A by the enhancer in either aqueous or ethanol/water formulation. Cyclosporin A was prohibitively insoluble in aqueous media and the activity of the enhancer is diminished to ineffectiveness when it is applied in alcoholic media. However, n-decylmethyl sulfoxide action on the stratum corneum could be obtained by pretreating the skin. The effect of pretreatment with this compound on the permeation of cyclosporin A through hairless mouse skin and human skin was studied with side-by-side diffusion cells. The skin was pretreated with 10 mM n-decylmethyl sulfoxide for various durations. Cyclosporin A in an ethanol/water formulation was then placed in the donor cell, with the amount of ethanol being controlled to maintain the highest possible thermodynamic activity. Accumulations of cyclosporin A in receiver cell media, aqueous or ethanol/water, were then assessed. Permeation from two different concentrations of cyclosporin A was compared. The permeability of hairless mouse skin to cyclosporin A was increased by the pretreatment, but results with human skin were more equivocal. It appears that it will take very long pretreatments to ready human skin for topical cyclosporin A therapy.