cssi/SciSciGPT-SciSciNet huggingface dataset:
Residual Stress Numerical Simulation Of Two Dissimilar Metal Weld Junctions

In nuclear reactors such as Pressurized Water Reactors (PWR), heavy section components made in low alloy steel are connected with stainless steel piping systems. The dissimilar material weld (DMW) junctions are performed following a special manufacturing procedure to ensure a good resistance of the joint. However, several experiences from the field confirm sensitivity to fatigue, corrosion or low toughness areas in this type of junction.
On the Whats and Hows of Where: The Role of Salience in Spatial Descriptions

According to Clark [1] language is a joint activity between speaker and listener, undertaken to accomplish a shared goal. In the case of spatial descriptions, one such goal is for a speaker to assist a listener in finding a sought-for object. For example, imagine misplacing your keys on a cluttered desktop, and asking your friend if s/he knows where they are. In response, there are a variety of spatial descriptions that your friend can select that vary in complexity, ranging from a simple deictic expression such as "there" (and typically accompanied by a pointing gesture), to a much more complicated description such as "its on the desk, under the shelf, to the left of the book and in front of the phone." Between these two extremes are descriptions of the form "The keys are by the book", consisting of three parts: the located object that is being sought (i.e., the keys); the reference object from which the location of the located object is specified (i.e., the book) and the spatial term that conveys the spatial relation between these two objects (i.e., by). For inquiries of this type ("where are my keys?"), the located object is pre-specified, but the speaker needs to select an appropriate spatial term and an appropriate reference object. My research focuses on the representations and processes by which a speaker selects these spatial terms and reference objects, and the representations and processes by which a listener comprehends these ensuing descriptions.
Trichophytin sensitivity of the immediate wheal type; report of a case with unusual manifestations and response to hydrocortisone.

Abstract A case report is presented of a 59-year-old white woman with a ten-year history of recurrent episodes of crural fungus infections with secondary erythematous-edematous lesions of the buttocks, thighs, forearms, and flexor surfaces of the elbows and knees. Trichophyton gypseum was cultured from the crural lesions, and intracutaneous testing with trichophytin extracts resulted in an immediate positive wheal-flare response and a negative forty-eight-hour delayed type reaction. The presence of circulating reagins to trichophytin could not definitely be proved. Evidence is presented to suggest that this represents an unusual type of dermatophytid characterized by fixed tissue sensitization. The secondary erythematous-edematous "id" lesions responded dramatically to orally administered hydrocortisone, while the primary fungus infection was unaffected by the adrenal corticosteroid therapy.
Security goals and protocol transformations

Cryptographic protocol designers work incrementally. Having achieved some goals for confidentiality and authentication in a protocol Π1 , they transform it to a richer Π2 to achieve new goals. But do the original goals still hold? More precisely, if a goal formula Γ holds whenever Π1 runs against an adversary, does a translation of Γ hold whenever Π2 runs against it? We prove that a transformation preserves goal formulas if a labeled transition system for analyzing Π1 simulates a portion of an lts for analyzing Π2 , while preserving progress in that portion. Thus, we examine the process of analyzing a protocol Π. We use ltss that describe our activity when analyzing Π, not that of the principals executing Π. Each analysis step considers--for an observed message reception--what earlier transmissions would explain it. The lts then contains a transition from a fragmentary execution containing the reception to a richer one containing an explaining transmission. The strand space protocol analysis tool cpsa generates some of the ltss used.
Analysis of the 60 S ribosomal protein L27a (L29) gene of Trypanosoma brucei.

Abstract The Trypanosoma brucei gene encoding the 60 S ribosomal protein L27a (L29) homologue has been cloned and characterised. The complete open reading frame encodes a small basic protein of 145 amino acids with a predicted molecular weight of 15950. The L27a amino acid sequence shares 45–58% identity with other L27a (L29) homologues. Southern blot hybridisation suggests that the gene is present in multiple copies. Northern blot analysis of RNA from three T. brucei life cycle stages show that mRNA levels are two-fold higher in procyclic than in early or late bloodstream stages. This infers that this highly conserved ribosomal protein may play an important role in translational regulation through the life cycle of trypanosomes.
Directly-Linked Gas Chromatography–Infrared–Mass Spectrometry (GC/IR/MS)

Directly linked gas chromatography-infrared-mass spectrometry (GC/IR/MS) is well established as a technique that fills a unique niche in the field of complex mixture analysis and structure elucidation. Although the method is not well suited for trace analysis, it has proved especially useful for analytical applications that are not sample limited. Commercial analysis systems based on this approach have gained acceptance and it is expected that continuing advances in the fields of chromatography and spectral detection will lead to improved GC/IR/MS systems in the future. This article reviews the history of GC/IR/MS development and briefly surveys the various approaches including lightpipe and matrix isolation methods. The use of complementary information is stressed and multidimensional GC/IR/MS discussed. Examples of applications include flavor and fragrance analysis, isomer identification, and pyrolysis product identification. Keywords: matrix-isolation; multidimensional analysis; cryogenic trapping; unleaded gasoline; flavors; fragrance; GC/IR/MS
Stability of prostaglandin I2 in human blood

Prostaglandin I2 (PGI2) is hydrolyzed more slowly in human plasma than in buffer at the same pH; this stabilization appears to be due to binding of PGI2 to albumin. The stability of the antiaggregatory potency of PGI2 is similar in human blood and in plasma buffered to pH 7.55. No measurable conversion of [3H]-PGI2 to radioactive or nonradioactive metabolites occurred during incubation with blood.
On the Diastereoselectivity of Ru-Catalyzed [5 + 2] Cycloadditions

[reaction: see text]. Ru-catalyzed cycloisomerization of cyclopropylenynes proceeds with good to high diastereoselectivities to form hexahydroazulenes.
Development of a Two-Stage Virtual Impactor System for High Concentration Enrichment of Ultrafine, PM2.5, and Coarse Particulate Matter

A two-stage particle concentration enrichment system was developed to provide highly concentrated particles at low flow rates, for applications in areas such as toxicity studies of particulate matter (PM) as well as for increasing the signal-to-noise ratio in online particle sampling instruments. The current system is an extension of the Versatile Aerosol Concentration Enrichment System (VACES) developed at University of Southern California and operates by placing a second-stage miniature virtual impactor (VI) downstream of the VACES. Particles are sequentially enriched through each stage. Laboratory evaluations were conducted using various types of polydisperse particles to simulate typical ambient PM components as well as monodisperse polystyrene latex (PSL) particles. The system's configuration was tested by adjusting the intermediate flow rate, which is the intake flow of the second-stage VI (or minor flow of the first-stage VIs), for which 15 L/min was determined to be optimal in terms of maximizing ...
Distal Pancreatectomy: Indications and Outcomes in 235 Patients

ObjectiveDistal pancreatectomy is performed for a variety of benign and malignant conditions. In recent years, significant improvements in perioperative results have been observed at high-volume centers after pancreaticoduodenectomy. Little data, however, are available concerning the current indicat
Fluorometric determination of carbohydrates.

Abstract Fluorometric methods are described for the determination of the enzymes hexokinase and β-glucosidase, and the carbohydrates glucose, fructose, maltose, cellobiose, lactose, glycogen, and salicin Glucose and fructose are determined fluorometrically using hexokinase and the resazurin-resorufin indicator reaction. Maltose, cellobiose, lactose, glycogen, and salicin are enzymically hydrolyzed to glucose, which is then determined fluorometrically using glucose oxidase, p-hydroxyphenylacetic acid, and peroxidase. All the carbohydrates were assayed in the range 0.01–50 μg/ml and the enzymes hexokinase and β-glucosidase in the range 10−3 to 10−1 unit/ml with an accuracy and precision of about 1.5%.
Unifying the derivations for the Akaike and corrected Akaike information criteria

Abstract The Akaike (1973, 1974) information criterion, AIC, and the corrected Akaike information criterion (Hurvich and Tsai, 1989), AICc, were both designed as estimators of the expected Kullback-Leibler discrepancy between the model generating the data and a fitted candidate model. AIC is justified in a very general framework, and as a result, offers a crude estimator of the expected discrepancy: one which exhibits a potentially high degree of negative bias in small-sample applications (Hurvich and Tsai, 1989). AICc corrects for this bias, but is less broadly applicable than AIC since its justification depends upon the form of the candidate model (Hurvich and Tsai, 1989, 1993; Hurvich et al., 1990; Bedrick and Tsai, 1994). Although AIC and AICc share the same objective, the derivations of the criteria proceed along very different lines, making it difficult to reconcile how AICc improves upon the approximations leading to AIC. To address this issue, we present a derivation which unifies the justifications of AIC and AICc in the linear regression framework.
A transmission and scanning electron microscopic study of cytoplasmic threads of dividing neuroepithelial cells in early chick embryos.

Cytoplasmic threads found on the luminal surface of the developing chick neuroepithelium contain a remnant of the spindle complex and an electron-dense midbody. Most threads become long and thin and eventually split at the midbody. This finding suggests that the midbody plays a role in the final separation of daughter cells.
Preparation and Performance of a Homogeneous Silicon Minimum-Ionizing Particle Detector

Following up on the work of C. R. Sun1 , we are investigating the performance of homogeneous, high-resistivity, silicon crystals as detectors for minimum-ionizing particles. In particular we are considering such a detector for use in conjunction with the operation of a hydrogen bubble chamber. Such devices would have the advantages of good spatial resolution, compactness, and stable performance in high magnetic fields. Operation would be at liquid nitrogen temperature. The detectors are cut as 2.5 mm thick wafers from an n-type ingot ~1.8 cm in diameter and with a typical resistivity of 1000 to 3000 ohm-cm. Nickel ohmic contacts are applied to each side of the wafer by a chemical plating process. In order to keep the dark current to a minimum, we try to raise the resistivity of the prospective detector close to the intrinsic level. This is accomplished by exposing the silicon, at 25°C, to a high flux of ? radiation from a Co60 source. Typically, after an exposure of 1.5 × 107 roentgens the silicon will have a resistivity of 4.0 × 106 ohm-cm at liquid nitrogen temperature (78°K). Using a charge sensitive amplifier, we observe pulse rise times of the order of 150 nanoseconds and signal to noise ratios greater than 10. There exists a "critical exposure level," C.E.L., for the ? irradiation. For radiation dosages greater than the C.E.L., the detector performance deteriorates. It seems possible to determine the C.E.L. conveniently by checking the detector resistivity at 25°C; for when the C.E.L.
Processing, structure and properties of Ni-W alloys fabricated by mechanical alloying and hot-isostatic pressing

The structure and properties of Ni-W alloys fabricated through MA and subsequent consolidation of the alloyed powders have been investigated. In comparatively W rich alloys, extensive solid solution of W in Ni accompanies MA and there is also evidence of partial or complete amorphization taking place during milling. During consolidation of these powders, W and an intermetallic (based on NiW) precipitate from the glassy matrix, which itself crystallizes. As-consolidated hardnesses of such materials are higher, by quite a bit, than the hardnesses of WHA formed via LPS. Structures obtained following consolidation remain nonequilibrium in that the W content of the matrix exceeds the equilibrium low temperature solubility and NiW is not stable at the post-consolidation heat-treatment temperature employed. This heat-treatment results in a gradual approach to the equilibrium structure and an increase in material microstructural scale. It is also accompanied by significant decreases in material hardnesses.
Hydrogen Peroxide Regulates Extracellular Superoxide Dismutase Activity and Expression in Neonatal Pulmonary Hypertension

Abstract We previously demonstrated that superoxide and H2O2 promote pulmonary arterial vasoconstriction in a lamb model of persistent pulmonary hypertension of the newborn (PPHN). Because extracellular superoxide dismutase (ecSOD) augments vasodilation, we hypothesized that H2O2-mediated ecSOD inactivation contributes to pulmonary arterial vasoconstriction in PPHN lambs. ecSOD activity was decreased in pulmonary arterial smooth muscle cells (PASMCs) isolated from PPHN lambs relative to controls. Exposure to 95% O2 to mimic hyperoxic ventilation reduced ecSOD activity in control PASMCs. In both cases, these events were associated with increased protein thiol oxidation, as detected by the redox sensor roGFP. Accordingly, exogenous H2O2 decreased ecSOD activity in control PASMCs, and PEG-catalase restored ecSOD activity in PPHN PASMCs. In intact animal studies, ecSOD activity was decreased in fetal PPHN lambs, and in PPHN lambs ventilated with 100% O2 relative to controls. In ventilated PPHN lambs, administ...
Pediatric resident and faculty attitudes toward self-assessment and self-directed learning: a cross-sectional study

The development of self-assessment and self-directed learning skills is essential to lifelong learning and becoming an effective physician. Pediatric residents in the United States are now required to use Individualized Learning Plans (ILPs) to document self-assessment and self-directed learning. A better understanding of resident and faculty attitudes and skills about self-assessment and self-directed learning will allow more successful integration of lifelong learning into residency education. The objective of this study was to compare faculty and resident attitudes, knowledge and skills about self-assessment, self-directed learning and ILPs. Survey of pediatric residents and faculty at a single institution. Respondents rated their attitudes, knowledge, and self-perceived skills surrounding self-assessment, self-directed learning and ILPs. Overall survey response rate was 81% (79/97); 100% (36/36) residents and 70% (43/61) faculty. Residents and faculty agreed that lifelong learning is a necessary part of being a physician. Both groups were comfortable with assessing their own strengths and weaknesses and developing specific goals to improve their own performance. However, residents were less likely than faculty to continuously assess their own performance (44% vs. 81%; p < 0.001) or continuously direct their own learning (53% vs. 86%; p < 0.001). Residents were more likely than faculty to believe that residents should be primarily responsible for directing their own learning (64% vs. 19%; p < 0.0001), but at the same time, more residents believed that assigned clinical (31% vs. 0%; p < 0.0001) or curricular (31% vs. 0%; p < 0.0001) experiences were sufficient to make them competent physicians. Interns were less likely than senior residents to have a good understanding of how to assess their own skills (8% vs. 58%; p = 0.004) or what it means to be a self-directed learner (50% vs. 83%; p = 0.04). Qualitative comments indicated that while ILPs have the potential to help learners develop individualized, goal-directed learning plans based on strengths and weaknesses, successful implementation will require dedicated time and resident and faculty development. These findings suggest that training and experience are necessary for physicians to understand the role of self-directed learning in education. Deliberate practice, for example by requiring residents to use ILPs, may facilitate self-directed, lifelong learning.
Systematic analysis of global features and model building for recognition of antimicrobial peptides

With growing bacterial resistance to antibiotics, it is becoming paramount to seek out new antibacterials. Antimicrobial peptides (AMPs) provide interesting templates for antibacterial drug research. Our understanding of what it is that confers to these peptides their antimicrobial activity is currently poor. Yet, such understanding is the first step towards modification or design of novel AMPs for treatment. Research in machine learning is beginning to focus on recognition of AMPs from non-AMPs as a means of understanding what features confer to an AMP its activity. Methods either seek new features and test them in the context of classification or measure the classification power of features provided by biologists. In this paper, we provide a rigorous evaluation of features provided by a biologist or resulting from a combination of experimental and computational research. We present a statistics-based approach to carefully measure the significance of each feature and use this knowledge to construct predictive models. We present here logistic regression models, which are capable of associating probabilities on whether a peptide is antimicrobial or not with the feature values of the peptide. We provide access to the proposed methodology through a web server. The server allows users to replicate the findings in this paper or evaluate their own features.We believe research in this direction will allow the community to make further progress and elucidate features that capture antimicrobial activity. This is an important first step towards assisting modification and/or de novo design of AMPs in the wet laboratory.
Lack of DNA adduct formation in mice treated with benzene.

The potential of benzene to produce DNA adducts in B6C3F1 mice was investigated by the nuclease P1-enhanced 32P-postlabeling assay. The mice were daily treated i.p. with 500 mg/kg benzene in olive oil for 4 days, and the liver, mammary gland, and bone marrow were collected 24 h after the last treatment. Thin-layer chromatograms obtained with treated-tissue DNA specimens were qualitatively identical to those from corresponding olive oil-treated (control) tissue DNA. Quantitative evaluations revealed that there was no treatment-related increase in radioactivity on the chromatograms at or near the locations where the major in vitro adducts of phenol, hydroquinone and benzoquinone migrated. Benzene treatment, however, resulted in a decrease in the levels of certain endogenous adducts, the biological significance of which is unknown. Our results indicate that benzene treatment does not produce detectable levels of aromatic DNA adducts in mouse tissues.
Massive Data Visualization

The old proverb, "And out of mind as soon as out of sight," attributed to Lord Brooke (1554(1628) generally referred to the passing of evil or harm. In the context of large-scale data analysis and simulation, however, it might foreshadow the loss of important information. The focus of this issue of CiSE is on the use and development of visualization techniques for exploring and managing large-scale scientific and textual information. The four articles comprising this issue demonstrate four different approaches to the visualization of scientific data from applications such as landscape ecology, text retrieval, cosmology, computational chemistry, and material science.
Mediterranean pollution: Problem and response

Abstract International efforts aimed at control of pollution of the Mediterranean Sea are unique in the extent to which politically diverse coastal states and a wide variety of international agencies are implementing cooperative programs of scientific research, education and training, planning, and treaty drafting. Continuing environmental cooperation in the Mediterranean reflects the political utility of pollution as a regional issue. Governments, the Mediterranean scientific community, and international organizations derive common benefits from maintaining the momentum of the United Nations Environment Programme‐sponsored activities, despite declining global interest in environmental concerns.
Neutron transfer reactions at large distances

[sup 58]Ni-induced one- and two-neutron transfer reactions have been measured on [sup 232]Th at [ital E][sub lab]=500 MeV. The transfer probabilities at large internuclear distances measured for the deformed [sup 232]Th target are compared with similar data on spherical [sup 208]Pb. For one-neutron transfer reactions good agreement between experiment and the prediction from the tunneling model is observed in both cases. The transfer probabilities for two-neutron transfer reactions deviate from the semiclassical predictions. The disagreement increases at higher bombarding energies. These deviations can be explained by the influence of diffractive effects which become more important at higher bombarding energies.
Oxygen reduction reaction on a mini gas diffusion electrode

Abstract A mini gas diffusion electrode (M-GDE) which is accessible to gaseous reactants and electrolyte has been developed for studying fuel cell catalysts and reactions by simply depositing catalyst ink onto a gas diffusion substrate of around a millimeter in diameter. Analogous to traditional gas-diffusion electrodes, the M-GDE comprises a carbon-paper gas diffusion layer and a catalyst-ink derived catalyst layer but with considerably decreased geometric surface area. The M-GDE has been characterized using electrochemical oxygen reduction reaction ( orr ) on carbon-supported platinum in sulfuric acid solution as a probe reaction. On the steady-state voltammograms, no diffusion-limiting currents are observed over a wide potential range of 0.7–0.95 V which is relevant to fuel cell operations. The absence of the diffusion limiting currents suggests that the interfacial oxygen mass transport is fast and the measured currents could be directly used for kinetic analysis without the need of mass transport correction. The Tafel plot exhibits two linear regions—a wide region with a slope of around 2RT / F followed by a narrow region with a slope of around 2 × 2 RT / F at higher overpotentials. This Tafel behavior is similar to literature results for the orr on ordinary gas diffusion electrodes. The mass activities and specific activities of the carbon-supported platinum for the orr directly measured from the steady-state voltammograms are consistent with literature data measured under similar conditions. All these facts strongly indicate that the M-GDE is a promising technique for the investigations of fuel cell reactions and nanosized catalysts at gas–catalyst–electrolyte interfaces. It retains the advantages of gas diffusion electrodes and provides the convenience of a microelectrode.
Hyperbolas and hyperbole: The free will problem remains

Hyperbolic theories have the fatal flaw that because of their vertical asymptote they predict irresistible choice of immediate rewards, regardless of future contingencies. They work only for simple situations. Theories incorporating intermediate unconscious choices are more flexible, but are neither exponential nor hyperbolic in their predictions. They don't solve the free will paradox, which may be just a consistent illusion.
Linear Mixed-Effects Models for Paint Pavement-Marking Retroreflectivity Data

The objective of this paper is to present an improved paint pavement-marking retroreflectivity degradation model. Previous degradation-modeling methods were reviewed and studied. The paint-marking retroreflectivity data were collected on 25 two-lane rural highways in North Carolina from November 2007 to May 2010. A linear mixed-effects model (LMEM) was selected as most appropriate for the paint-marking retroreflectivity data. The LMEM took into account the correlation among repeated measurements of the data set and produced more accurate predictions than other methods. LMEMs were established for white edge and yellow center paint pavement markings. The LMEM results showed that the estimated white edge pavement marking life cycle is 37.5 months and yellow center marking life cycle is 38.9 months on average when using 100 and 65 mcd/m2/lx as the minimum acceptable retroreflectivity values for white and yellow paint markings. A model comparison indicated that the LMEM provided a more accurate prediction tha...
Understanding the Gap in Special Education Enrollments Between Charter and Traditional Public Schools: Evidence From Denver, Colorado

A widely cited report by the federal Government Accountability Office found that charter schools enroll a significantly smaller percentage of students with disabilities than do traditional public schools. However, thus far no hard evidence exists to definitively explain or quantify the disparity between special education enrollment rates in charter and traditional public schools. This article uses student-level data from Denver, Colorado, to map the creation and growth of the special education gap in elementary and middle school grades. The gap begins because students with disabilities are less likely to apply to charter schools in gateway grades than are nondisabled students. However, the special education gap in Denver elementary schools more than doubles as students progress between kindergarten and the fifth grade. About half of the growth in the gap in elementary grades (46%) occurs because of classification differences across sectors. The remaining 54% of the growth in the gap in elementary grades i...
The shaking palsy, the first forty-five years: A Journey through the british literature

The authors examined the British medical literature published in the 45-year-period following Parkinson's treatise on the shaking palsy to determine the number and type of references to the shaking palsy or paralysis agitans during this particular period. Several sources suggest that Parkinson's 1817 treatise on the shaking palsy received little immediate attention in his native country, England, and that not until 1861, in France, did Charcot began to elucidate the clinical features of this entity, separating it from other neurologic disorders (for example, multiple sclerosis). A review of the British medical literature from the 45-year-period 1817-1861 revealed a number of references to paralysis agitans, including those by Cooke (1820), Good (1824 and 1829), Elliotson (1827, 1829, 1830, 1831, and 1833), Gowry (1831), anonymous (1832), Todd (1833), Watson (1836), Gibson (1839), Hall (1838 and 1841), Thompson (1842), Graves (1843), Birkett (1853), Paget (1855), and Reynolds (1855). Many of these did not report new or personally observed cases, did not separate Parkinson's disease from other disease entities characterized by both "shaking" and "palsy" (for example, tonic-clonic seizures), or misattributed motor signs to dysfunction of the pyramidal system rather than an extrapyramidal system (that is, attributing bradykinesia or rigidity to weakness). Although there were several references to "shaking palsy" in the early- to mid-19th-century British medical literature, there were few original case reports of Parkinson's disease. This may have contributed to the fact that during this period little was added to the original observations made by Parkinson in 1817. In particular, the separation of bradykinesia and weakness did not become apparent until later work by the French.
The Pugilist and the Cosmologist: Response to Loïc Wacquant’s ‘Homines in extremis’

This article investigates Loic Wacquant’s suggestion that ‘thinking is a deeply corporeal activity’ by showing how theoretical activities mobilize different bodies in practice, in both the natural and social sciences. It argues that knowledge is about exchanges of properties between different entities or bodies by drawing a parallel here between the sociologist (Loic Wacquant) becoming his object of study and scientists becoming the objects they study. It also examines the reverse movement; that is, we have to invent devices to escape the hic et nunc of the body to project ourselves into other times and spaces. The article concludes by questioning Wacquant’s conception of ‘scientific knowledge’ by tracing a number of dichotomies present in his work: mind/body, subject/object, theory/practice. An alternative conception of the knowing subject is then formulated, one that is neither a transcendental subject nor a ‘socialized body’; I call this the distributed centered subject.
Data and Wisdom: Electronic Editing and the Quantification of Knowledge

The concept of data in the humanistic academy carries a heavy cultural freight: as a reductionist yet efficient representation of complex textual significance. Far from being an invention of the digital age, this conception of the role of quantification has a prehistory whose terms continue to resonate in modern debates about digital editing and digitally mediated scholarship. This essay explores these terms and the anxieties they reflect, concluding that digital representation is no less textually and methodologically rich, and no less a production of knowledge, than its print counterpart.
Economic conditions and punishment in Postbellum Georgia

This paper examines the relationship between economic conditions and incarceration in Georgia between 1868 and 1936. Time-series analysis provides evidence that declining cotton prices increased the rate at which both black and white males were incarcerated. Changes in cotton production, declines in racial economic inequality, and demographic shifts also affected incarceration rates. Each had quite different implications for black and white punishment, however. The paper concludes with a discussion of the implications of these findings for research on punishment in general and Southern punishment in particular.
Balloon mania: news in the air

The hot-air balloon, invented by the Montgolfier brothers in 1783, enabled the French King to project his glory, the nobility to exhibit their valor, the literary public to transmit the ideal of the Enlightenment and the plebian public to rejoice in a scientific spectacle. The ensuing balloon mania helped create an integrated public that, because of its size and composition, can only be described as 'democratic' just a few years before the French Revolution. The monumental impact of the balloon was well represented in a flood of poetry, pamphlets, books, journal reports, academic papers and consumer items. Sifting through these artifacts and considering the crowd that witnessed the ascent of the balloon will bring us to the historical moment when things, spectacles, and events (rather than words) shaped public and popular opinion.
The Mechanism of the Self-Initiated Thermal Polymerization of Styrene. Theoretical Solution of a Classic Problem

The Mayo and Flory mechanisms for the self-initiation of styrene polymerization were explored with B3LYP and BPW91 density functional calculations. The Diels−Alder dimer (AH) is the key intermediate, and the lowest energy pathway for AH formation is a stepwise mechanism via a gauche/sickle (•M2•Gs) or gauche/U-shaped (•M2•Gu) diradical. Ring closure of the 1,4-diradical to diphenylcyclobutane (DCB) is predicted to have a lower barrier than ring closure to AH. Dynamic effects are likely to play an important role in determining the rate of AH versus DCB formation. Hydrogen transfer from AH to styrene to generate two monoradical species is predicted to be a reasonable process that initiates monoradical polymerization.
The potential energy surface of singlet cyclobutadiene and substituted analogs: a coupled-cluster study

Coupled-cluster investigations (CCSD/cc-pVDZ and CCSD/cc-pVQZ//CCSD/cc-pVDZ) of singlet cyclobutadiene and fifteen-substituted analogs were conducted. A local minimum with a square frame does not exist on their potential surfaces. The well-known rectangular D2h minimum, the square D4h transition state, and two additional stationary points were found on cyclobutadiene’s potential surface. This included a transition state with a rhombic carbon ring and C2h symmetry, separating two equivalent puckered C2v local minima. The predicted barriers were 19.7 and 19.8 kcal/mol at the CCSD/cc-pVDZ and CCSD/cc-pVQZ//CCSD/cc-pVDZ levels, respectively. The relative strain energies of rectangular D2h cyclobutadiene and all fifteen-substituted analogs were obtained from isodesmic reactions. Progressive substitution with methyl or BH2 groups continuously lowers ring strain while increasing substitution with fluorines or trifluoromethyl groups steadily increases ring strain. C4(BH2)4 is 16.6 and 13.3 kcal/mol less strained than cyclobutadiene while C4F4 is 17.7 and 21.5 kcal/mol more strained at the levels above. Cyclobutadiene is more strained than both cyclopropene and cyclobutene by 12.2 and 37.0 kcal/mol, respectively. Electron density contours indicate that fluorine substitution raised the electron density especially in the short C=C ring bonds above/below the ring plane (π-electrons) but not in the ring plane (σ-electrons). BH2-substitutions lower the ring π-electron density with little effect in the ring plane. Methyl substituents have little effect on electron densities. All rings retain a strong bond alternation tendency (rectangular) whether substituted with electron-donating or -attracting groups. One-bond coupling constants and the percent p-character in ring C-to-C and C-to-substituent bonds are described.
Ring-Expanded Nucleoside Analogues. 1,3-Dioxan-5-yl Pyrimidines

1,3-Dioxan-5-yl pyrimidine nucleoside analogues, higher homologues of antiviral and anticancer 1,3-dioxolanes, were prepared from bis-1,3-tritylglycerol and 3-benzoylated bases (uracil, 5-fluorouracil, thymine). Mitsunobu condensation, deprotection, and cycloacetalization gave cis/trans mixtures of 2,5-disubstituted-1,3-dioxanes in which the desired cis stereoisomers predominated. Cytosine derivatives could not be obtained in this manner; N4-benzoylcytosine afforded an O-2 alkylated Mitsunobu product that rearranged to an O2-(2,3-dihydroxypropyl)cytosine on detritylation with aqueous acetic acid. Cytosine and 5-fluorocytosine nucleosides were therefore prepared from the corresponding uracils via their 1,2,4-triazole derivatives. 1H NMR data established the conformational preference for equatorial 2‘-hydroxymethyl and axial 5‘-base in the cis isomers; the trans compounds were diequatorial. Despite their conformations, the cis nucleosides showed no antiviral activity.
Modifications of the Timoshenko beam equations necessary for thin-walled circular tubes☆

Abstract It is shown that the conventional form of the Timoshenko beam equations, unless modified to account for normal pressure and Poisson ratio effects, cannot be applied to thin-walled circular tubes. An important implication of this result is that a thin-walled beam has three characteristic wave speeds instead of just the two predicted by the unmodified Timoshenko equations. The effect of the modifications is illustrated by a plot showing the variation with length of the natural frequencies of a simply supported tubular beam.
Expression of PC3, carboxypeptidase E and enkephalin in human monocyte-derived macrophages as a tool for genetic studies

Circulating monocytes in human peripheral blood are readily available, easily obtained, and can be cultured in vitro. Once plated, the monocytes spontaneously differentiate into macrophages. Undifferentiated human monocytes do not express carboxypeptidase E (CPE), prohormone convertase 3 (PC3/PC1) or proenkephalin (ENK), suggesting that gene induction during differentiation results in the expression of these genes. RT-PCR of human monocyte-derived macrophage (HMDM) mRNA showed detectable levels of ENK mRNA at 48 h after plating, followed by PC3 and CPE mRNAs at 72 h. PC3 expression was confirmed by Western blotting in THP-1 cells. Similarities in expression of enzymes involved in the conversion of neuroendocrine precursors, such as proenkephalin, into functionally mature peptides underscores the close association HMDMs may share with the neuroendocrine system. Because of this, HMDMs may prove to be a valuable, non-surgical source of human tissue for clinical genetic diagnosis of some convertase disorders.
Analogue state resonances in the (p,po) and (p,p') processes

Abstract Analogue state resonances in the (p,po) and (p,p') processes are analyzed in terms of extended coupled- channel calculations. The way to extract the spectroscopic factors is also discussed.
The tobacco withdrawal syndrome: performance decrements assessed on a computerized test battery

The effects of tobacco abstinence and resumption of smoking on cognitive performance were studied in seven cigarette smokers. Subjects were trained on a computerized performance assessment battery (PAB) that included five different tests. Baseline data were obtained under conditions of minimally restricted cigarette smoking. This baseline smoking phase ended at 1000 h on the first day of tobacco deprivation and the PAB was then administered at intervals of 1, 4 and 8 h, and once at 1000 h on each of the next 9 days. Upon resumption of smoking (1000 h on day 11), testing was conducted at intervals of 1, 4, 8 and 24 h. The main findings were that tobacco deprivation resulted in significantly increased response latencies on all of the tests and decreased accuracy on two tests. Some performance impairments were observed within 4 h after the start of the smoke deprivation phase. Impairments peaked at 24-48 h and then begun to return toward baseline values; however, some measures remained significantly changed throughout the 10 days of abstinence. Performance decrements that were still evident throughout the deprivation phase were at least partially reversed after 1 h of resumption of smoking; all values returned to baseline levels within 24 h of resumption of smoking.
Broadening our lenses of perception to advance learning: An introduction to multilectics

Abstract In Broadening our lenses of perception , I address the need to assess students through multiple lenses rather than through the dominant lens of standardized tests. I propose what I call multilectical lenses to provide multidimensional pictures of poor students of color; these highlight student skills and knowledge that tests disregard. Multilectics employs multi level analysis, sound and images to analyze the gestures and voices of students during classroom activities. In combination with student writing, the data produced by multilectical practice provide a rich foundation for advancing the academic achievement of our most underserved students.
Repetition and depth of processing

This paper is an empirical and theoretical critique of the depth-of-processing view ( Craik & Lockhart, Journal of Verbal Learning and Verbal Behavior, 1972 , 11, 671–684). Three new experiments demonstrate that repetition at the phonemic depth of processing does facilitate memory, regardless of whether the repetitions are massed or distributed and regardless of whether the dependent variable is uncued recall, cued recall, or recognition. Previous studies reporting null effects of repetition are reviewed and called into question. These results, combined with logical shortcomings in the principle that deeper processing facilites memory, imply that the current view of depth of processing is not valid as a scientific theory, explanation, or description of the available data.
Geometric manipulation of ensembles of atoms on an atom chip for quantum computation

We propose a feasible scheme to achieve quantum computation based on geometric manipulation of ensembles of atoms and analyze it for neutral rubidium atoms magnetically trapped in planoconcave microcavities on an atom chip. The geometric operations are accomplished by optical excitation of a single atom into a Rydberg state in a constant electric field. Strong dipole-dipole interactions and incident lasers drive the dark state of the atom ensembles to undergo cyclic evolutions that realize a universal set of quantum gates. Such geometric manipulation turns out naturally to protect the qubits from the errors induced by nonuniform laser illumination as well as cavity loss. The gate performance and decoherence processes are assessed by numerical simulation.
High-capacity “hydro-blast” circuit breaker for central-station service

The increasing demand for oilless circuit breakers has resulted in a number of contributions in that field. Outstanding among these from the standpoint of interrupting capacity at generator voltages is the ``hydro-blast'' circuit breaker, which has been developed in ratings up to 1,500,000 kva. This breaker has the feature of complete interchangeability with the standard H-type oil circuit breaker and thus combines all of the well-known advantages of that type with the total absence of inflammable material. This paper describes in detail the construction and operation of the 500,000-kva hydro-blast circuit breaker for central-station service, several of which have been in service for over half a year.
Trapped atomic condensates with anisotropic interactions

We study ground-state properties of trapped atomic condensates with electric-field-induced dipole-dipole interactions. A rigorous method for constructing the pseudopotential in the spirit of ladder approximation is developed for general nonspherical (polarized) particles interacting anisotropically. We discuss interesting features not previously considered for currently available alkali-metal condensates. In addition, to provide a quantitative assessment for controlling atomic interactions with electric fields, our investigation may also shed a different light into the macroscopic coherence properties of the Bose-Einstein condensation (BEC) of dilute interacting atoms.
Freeze‐Agglomeration: An Alternative Mechanism for Clay Film Formation

Oriented clay coatings (argillans, clay cutans, clay films, lamellae) are often interpreted to be caused by illuviation (pervection, lessivage) of fine clay particles. In montane meadow soils (Typic Humaquepts) of the northern Sierra Nevada Range, prominent clay cutans occur on ped faces of a paleosol 3Btgb horizon, which is contemporaneous or younger than 2840 ± 220 yr BP by radiocarbon dating. The unlikelihood of distinct clay cutans forming in such a short period of time via illuviation in a soil with an aquic moisture regime suggests an alternative mechanism. Laboratory studies show that silt- and sand-sized agglomerates can be produced by subjecting colloidal kaolinite (high Fe content), extracted from the montane meadow soil, to repeated freeze–thaw cycles. These agglomerates have a distinct microgranular texture and one to several birefringent domains. Thin section microscopy of the surface Oa horizon reveals that pores and root channels are coated by oriented birefringent zones resembling clay cutans. These clay cutans are similar in optical properties to laboratory-produced freeze-agglomerates. Optical microscopy of clay cutans, scraped from the paleosol 3Btgb horizon, suggests that they too may have formed via freeze-agglomeration. Freezeagglomeration is proposed as a new mechanism to produce oriented clay films.
Capacity utilization and machine sharing in a group technology based manufacturing system

Abstract Each cell in a group technology-based manufacturing system can be assumed as being comprised of two categories of machine types: (a) Dedicated to the cell, (b) Shared by other cells. The shared machine types constitute the major problem in the implementation of a cellular manufacturing system. This paper demonstrates, using a hypothetical case study, a mathematical programming formulation that exploits the existence of shared machine types in a cellular manufacturing system. Part transfer for the parts whose output levels are restricted by available capacity or shared machine types can be found which will minimize the material handling penalties.
Short residence time of colloids in the upper ocean estimated from 238 U– 234 Th disequilibria

RECENT observations of abundant, nonliving, submicrometre particles in the upper ocean1–3 and new measurements of 'dissolved9organic carbon4–7 have fuelled speculation concerning the role of colloidal matter in ocean chemistry and biology. Colloids may act as reactive intermediates in the marine geochemistry of trace metals8–12, and a biologically labile pool of colloidal matter would affect models of ocean carbon cycling13–16. Here we report the use of naturally occurring 234Th as an in situ tracer to estimate the residence time of colloidal matter in the surface waters near Bermuda. The 234Th activity of colloidal matter (size range 10,000 nominal molecular weight to 0.2 μm) is similar to that of small particles (0.2–53 μm). Modelling of our results indicates a mean residence time of colloidal 234Th with respect to aggregation into small particles of 10 days, which is roughly the same as for small-particle 234Th, yet a factor of ∼6 less than for the dissolved pool. These results suggest that, more generally, macromolecular colloidal matter has a short residence time and hence a rapid turnover rate in the upper open ocean.
Correlating Cerebral 18 FDG PET-CT Patterns with Histological Analysis During Early Brain Injury in a Rat Subarachnoid Hemorrhage Model

Early brain injury (EBI) plays a significant role in poor outcomes for subarachnoid hemorrhage (SAH) patients. Further investigations are required to characterize the cellular metabolic and related histological changes that may contribute to EBI following SAH. We investigated the image patterns of 18-fluorodeoxyglucose positron emission tomography-computed tomography (18FDG PET-CT) during EBI and correlated histopathological changes utilizing a rat SAH model. SAH was induced in six adult male Sprague-Dawley rats by endovascular perforation, and animals were randomly assigned to receive 18FDG PET-CT imaging at either 3 or 12 h post-procedure. Mean 18FDG standard uptake value (SUV) of the brain was calculated. Animals were euthanized 48 h post-procedure, and brain samples were used for heme oxygenase-1 (HO-1) and dopamine- and cAMP-regulated phosphoprotein (DARPP-32) Mr 32 kDa immunohistochemistry. Rats within the SAH group had higher mean whole brain 18FDG SUV (2.349 ± 0.376 g/ml in the 3-h group and 2.453 ± 0.495 g/ml in the 12-h group) compared to that of sham (n = 3; mean SUV = 2.030 ± 0.247 g/ml; P 0.05). Regions of decreasing SUV in SAH rats correlated with neuronal death and increased expression of HO-1. Higher 18FDG PET SUV was evident in rats post-SAH compared to sham and control groups. Regions of decreasing SUV in SAH rats correlated with neuronal death and increased HO-1 expression as evaluated by histopathology.