cssi/SciSciGPT-SciSciNet huggingface dataset:
Venn said it couldn't be done.

The scope and content of ancient formal logic was determined by Aristotle's Organon and, in particular, the Doctrine of the Syllogism wlhiclh, as it has come to us, contains no diagrams. Nonetheless, so suiggestive is the language and imanner of presentation of the syllogistic schelm-a, that many logicians lhave speculated as to the possibility that Aristotle miiade use of spatial concepts in his actual lectures... . Isolated diagrams using somne formn of geometric figure to denote a proposition or syllogism occurred in the works of a number of sixteenth-century logiciaiis... . It was, lhowever, Gottfried Wilhelm Leibniz who first devoted serious study to the analysis of logical propositions by means of diagramns.
The relation between emotion work and hysteria: A feminist reinterpretation of Freud's Studies on Hysteria *

(1989). The relation between emotion work and hysteria: A feminist reinterpretation of Freud's Studies on Hysteria. Women's Studies: Vol. 16, No. 3-4, pp. 255-270.
Studies on biogenic amines and their metabolites in nervous tissue and hemolymph of male cabbage looper moths - II. Photoperiod changes relative to random locomotor activity and pheromone-response thresholds

Levels of octopamine, 5-hydroxytryptamine, dopamine and their metabolites were measured in brain, corpora cardiaca/corpora allata complex, thoracic ganglia and optic lobes from individual male cabbage looper moths, Trichoplusia ni, using HPLC with electrochemical detection. Measurements were made from individuals in late photophase and compared with levels from individuals at mid-scotophase. Individuals at mid-scotophase had been observed for locomotor activity throughout the dark period and then assayed in the sustained-flight tunnel with a low, threshold, dose of sex pheromone prior to dissection. Individuals were selected for dissection if they exhibited a complete upwind flight to the pheromone source, or if they did not respond at all. Mid-scotophase levels of octopamine in the brain and thoracic ganglia, dopamine in the thoracic ganglia, and 5-hydroxytryptamine in the brain and thoracic ganglia were all significantly lower than photophase levels. Scotophase levels of octopamine in individuals that responded to a low dose of pheromone were significantly lower than levels from males that did not respond. Levels of random locomotor activity over the scotophase were not correlated with the probability of a male responding to the threshold dose of pheromone. There also was no correlation between brain mid-scotophase levels of amines and the degree of locomotor activity exhibited, but there was a strong correlation between decreased levels of octopamine and dopamine in the thoracic ganglia and high levels of locomotor activity. Decreased levels of octopamine in the brain and thoracic ganglia over the dark period were correlated with increased levels of N-acetyloctopamine, suggesting that utilization of the amines occurs within the tissues over this time period. Mid-scotophase levels of N-acetyldopamine were significantly greater than photophase levels, suggesting increased metabolism of this amine as well. Our results indicate that changes in amine levels within specific tissues can be correlated with behaviors exhibited by individual insects. The results support the hypothesis that octopamine, dopamine and 5-hydroxytryptamine exert modulatory or transmitter roles in the central nervous system of the cabbage looper moth.
Structures of Gramicidins A, B, and C Incorporated Into Sodium Dodecyl Sulfate Micelles.

Gramicidins A, B, and C are the three most abundant, naturally occurring analogues of this family of channel-forming antibiotic. GB and GC differ from the parent pentadecapeptide, GA, by single residue mutations, W11F and W11Y, respectively. Although these mutations occur in the cation binding region of the channel, they do not affect monovalent cation specificity, but are known to alter cation-binding affinities, thermodynamic parameters of cation binding, conductance and the activation energy for ion transport. The structures of all three analogues incorporated into deuterated sodium dodecyl sulfate micelles have been obtained using solution state 2D-NMR spectroscopy and molecular modeling. For the first time, a rigorous comparison of the 3D structures of these analogues reveals that the amino acid substitutions do not have a significant effect on backbone conformation, thus eliminating channel differences as the cause of variations in transport properties. Variable positions of methyl groups in valine and leucine residues have been linked to molecular motions and are not likely to affect ion flow through the channel. Thus, it is concluded that changes in the magnitude and orientation of the dipole moment at residue 11 are responsible for altering monovalent cation transport.
A Developmental Germanium P-N-P Junction Transistor

A developmental germaniump-n-p junction transistor that may be readily made in the laboratory by alloying indium into opposite faces of a wafer of single-crystal n-type germanium is described. It is shown that this laboratory technique gives experimental transistors with desirable characteristics. Distribution curves of measured characteristics are given for a typical run of 118 units made and tested under similar conditions. Power gains up to 46 db, "alpha" up to 0.997, and noise factor (1 kc) as low as 6 db were achieved.
Real Time Two-Dimensional Echocardiography in the Diagnosis of Left Atrial Myxoma

A patient with a left atrial myxoma is reported in whom M-mode echocardiography was atypical and misleading since in most transducer positions, no tumor echoes were found in the left atrium. Real time two-dimensional echocardiography provided a definitive diagnosis, demonstrating a large left atrial mass with multiple areas of calcification. One such calcified area was located adjacent to the posterior aortic wall, and the tumor echoes were sparsely imaged directly behind it due to incomplete penetration of the ultrasound beam through dense calcification (acoustic shadowing). Difficulty in M-mode diagnosis appeared to result from this acoustic shadowing effect. In our patient, two-dimensional echocardiography was superior to the M-mode in making a definitive diagnosis of left atrial tumor because of the difficulty visualizing tumor echoes in the left atrium.
A survey of depressive symptoms among Vietnamese-American men in three locales: Prevalence and correlates

Vietnamese are one of the fastest growing ethnic minority groups in the United States. The purpose of this study was to determine the prevalence and correlates of high depression scores among Vietnamese men in three locales. Computer assisted telephone interviews were conducted with adult Vietnamese men in San Francisco/Alameda Counties, Santa Clara County, and the city of Houston. Telephone numbers of households with Vietnamese surnames were chosen randomly from area telephone books. Depression was assessed using a previously validated Vietnamese language depression screening instrument with 86% sensitivity and 96% specificity for major depression. Between 8.2% and 9.8% of the men scored above the cut-off. Logistic regression analysis revealed that men who were the least proficient in English, poorer, unemployed or disabled, veterans, and those living in Houston were more likely to have a high depression score. Based on the characteristics of the screening instrument, rates of clinical depression among Vietnamese men may be modestly higher than rates for men in the general population. However, high-risk subgroups identified by our analyses may suffer from substantially higher rates of clinical depression. To our knowledge, ours is the first study to show that community context or locale is an independent predictor of high depressive symptoms in this population. These findings have important implications for prevention and intervention approaches to depression among Vietnamese men.
Human chromosomal heteromorphisms in American Blacks VII. Correlation (r) between height and the size of the Y chromosome

Fifty normal American Blacks were selected to examine the correlation between the length of the Y chromosome and their height using QFQ technique. Chromosomes 19 and 20 (F group) and Y were measured directly from the film and Y/F indices were calculated as a parameter of Y length. The average length of the Y chromosome was 1.09. There was no correlation between the height of an individual with the length of his Y (p>.01). The biological and clinical significance of human Y chromosome heteromorphisms is discussed.
Moment features invariant to dispersion

As a wave propagates in a dispersive medium certain characteristics change and hence it may not be recognized as the same wave by different observers. For lossless dispersive propagation, temporal moments such as the mean time and duration of the wave change as a function of position, while frequency moments do not. We show that there are other moment-like temporal features of the wave that are also invariant to dispersion. These moments may be useful in automatic classification because indeed they are invariant to dispersive channel effects and hence do not depend on the position at which they are calculated, and they provide additional information beyond that given by frequency moments.
Familial occurrence of the rheumatoid factor

The inhibition test and the latex fixation test (by the authors' modification) were both found positive more frequently in relatives of rheumatoid patients than in control groups. The authors, having assumed that a positive rheumatoid inhibition test, i.e., failure of sera to inhibit the sheep cell test (amboceptor), is due to the presence of small quantities of rheumatoid agglutinator in the euglobulin fraction, concluded from this and from the results of the capillary latex fixation procedure that increased amounts of rheumatoid factor are present in members of families of patients with rheumatoid arthritis. Esseva constatate que tanto le test de inhibition como etiam le test de fixation a latex (in le modification usate per le autores) esseva plus frequentemente positive in consanguineos de patientes rheumatoide que in subjectos de controlo. Le autores opina que un positive test de inhibition rheumatoide—i.e. le non-inhibition, per le sero, del test a cellulas ovin—signala le presentia de micre quantitates de agglutinator rheumatoide in le fraction euglobulinic. Isto, insimul con le resultatos del manovra de fixation a latex, supporta le conclusion que augmentate quantitates de factor rheumatoide es presente in membros de familias de patientes con arthritis rheumatoide.
Development of posttraumatic empyema in patients with retained hemothorax: results of a prospective, observational AAST study.

BACKGROUND: The natural history of retained hemothorax (RH), in particular factors contributing to the subsequent development of empyema, is not well known. The intent of our study was to establish the modern incidence of empyema among patients with trauma and RH and identify the independent predictors for development of this complication. METHODS: An American Association for the Surgery of Trauma multicenter prospective observational trial was conducted, enrolling patients with placement of a thoracostomy tube within 24 hours of trauma admission, and subsequent development of RH was confirmed on computed tomography of the chest. Demographics, interventions, and outcomes were analyzed. Logistic regression analysis was used to identify the independent predictors for the development of empyema. RESULTS: Among 328 patients with posttraumatic RH from the 20 participating centers, overall incidence of empyema was 26.8% (n = 88). On regression analysis, the presence of rib fractures (adjusted odds ratio [OR], 2.3; 95% confidence interval [CI], 1.3-4.1; p = 0.006), Injury Severity Score of 25 or higher (adjusted OR, 2.4; 95% CI, 1.3-4.4; p = 0.005), and the need for any additional therapeutic intervention (adjusted OR, 28.8; 95% CI, 6.6-125.5; p < 0.001) were found to be independent predictors for the development of empyema for patients with posttraumatic RH. Patients with empyema also had a significantly longer adjusted intensive care unit stay (adjusted mean difference, 4.1; 95% CI, 1.3-6.9; p = 0.008) and hospital stay (adjusted mean difference, -7.9; 95% CI, -12.7 to -3.2; p = 0.01). CONCLUSION: Among patients with trauma and posttraumatic RH, the incidence of empyema was 26.8%. Independent predictors of empyema development after posttraumatic RH included the presence of rib fractures, Injury Severity Score of 25 or higher, and the need for additional interventions to evacuate retained blood from the thorax. Our findings highlight the need to minimize the risk associated with subsequent thoracic procedures among patients with critical illness and RH, through selection of the most optimal procedure for initial evacuation. LEVEL OF EVIDENCE: Prognostic study, level III.
Confessions and the creation of the will: A weird tale

This essay examines Augustine’s Confessions as a horror tale using a phenomenological methodology with the intent of showing that this text is the literary expression of the author’s philosophical concept of the will. Elements of the weird tale serve as a literary model for this essay, so that it reads in many ways like a horror tale relating Confessions’ horror tale. The main purpose of this approach is to de-familiarize this canonical and hegemonic text so we can escape its powerful spell and view it differently.
Goal-directed and stimulus-driven attention in cross-dimensional texture segregation.

Goal-directed and stimulus-driven control of attention was examined in a visual texture segregation task. Recent published reports have debated the existence and efficiency of goal-directed guidance of attention. Some of this research has focused on the apparent stimulus-driven attentional priority given to salient distractors, even when they are known to be irrelevant to the task. In the present study, subjects searched a texture array for targets defined along one dimension. These displays also included distractors created by variation in an irrelevant dimension. Targets were of three different overall shapes. On each trial, distractors could be the same shape as the target or one of the other two shapes. In two experiments subjects were informed of the overall shape of the target prior to stimulus presentation. In these experiments, distractors that did not match the overall shape of the target caused less interference than distractors that matched the target’s shape. In the third experiment, subjects were not informed of the overall shape of the target. In this experiment all distractors caused roughly equal interference. The results of these experiments demonstrate that if subjects are given information about the overall shape of the target, they are able to use this information to reduce interference from distractors that do not match the overall target shape. While acknowledging some stimulus-driven interference, this illustrates a previously unexplored source of goal-directed guidance that can reduce interfering effects of even salient distractors and argues against purely stimulus-driven control of attention.
A metadata-driven framework for generating field data entry interfaces in ecology

Abstract With the advent of affordable yet powerful handheld computers, many ecologists now capture data electronically in the field, while avoiding transcription errors found in more traditional field notebook or slate-based approaches of recording data. Ecologists either use simple forms from generic handheld software that doesn’t allow for needed optimizations, or else they must spend substantial effort in the design and optimization of handheld software user interfaces. These efforts often produce highly customized software that is not easily repurposed, and that produce non-standard, undocumented data formats. Our research is focused on reducing this effort by providing a flexible framework that uses highly structured metadata to drive the generation of customized data entry interfaces. Our approach relies on formalized metadata encoded in either XML Schema or XML instance documents, which facilitate the creation of graphical interfaces from arbitrary data schemas. Specifically, we leverage the rich metadata descriptions and structures found in the Ecological Metadata Language to create data entry forms, and output data sets that adhere to this specification. The interfaces are refined by using data-typing and domain information found in the structured metadata to generate validation routines that assist in maintaining data integrity during the entry process. The framework utilizes a rule-based engine to promote both reuse and extensibility of the modules that are created for any given data entry effort. Interfaces are rendered using open, Internet-based standards to maintain portability and to advocate the sharing of software components. The framework represents an initial implementation of a customizable user interface generator, which should have broad applicability to researchers in need of rapidly creating field and laboratory-based forms for varied collection efforts.
Emerging pathogens in nosocomial pneumonia.

The organisms responsible for nosocomial pneumonia are continuously evolving. Gramnegative bacilli have become the most common etiologic agents over the past 20 years, and with this evolution has come a better understanding of the pathogenesis of gram-negative bacillary pneumonia. Some gram-positive cocci, such as enterococci, group B beta hemolytic streptococci and methicillin-resistantStaphylococcus aureus, haven taken on new significance in nosocomial respiratory infections.Streptococcus pneumoniae, nontypeableHaemophilus influenzae andBranhamella catarrhalis are increasingly reported in hospitalized patients with chronic lung disease. Etiologic agents will change as new antibiotics are introduced. A better understanding of etiologic agents and their pathogens may be the best tool toward preventing hospital-acquired pneumonia.
The Hydrophilic Phosphatriazaadamantane Ligand in the Development of H2 Production Electrocatalysts: Iron Hydrogenase Model Complexes

As functional biomimics of the hydrogen-producing capability of the dinuclear active site in [Fe]H2ase, the FeIFeI organometallic complexes, (μ-pdt)[Fe(CO)2PTA]2, 1-PTA2, (pdt = SCH2CH2CH2S; PTA = 1,3,5-triaza-7-phosphaadamantane), and (μ-pdt)[Fe(CO)3][Fe(CO)2PTA], 1-PTA, were synthesized and fully characterized. For comparison to the hydrophobic (μ-pdt)[Fe(CO)2(PMe3)]2 and {(μ-H)(μ-pdt)[Fe(CO)2(PMe3)]2}+ analogues, electrochemical responses of 1-PTA2 and 1-(PTA·H+)2 were recorded in acetonitrile and in acetonitrile/water mixtures in the absence and presence of acetic acid. The production of H2 and the dependence of current on acid concentration indicated that the complexes were solution electrocatalysts that decreased over-voltage for H+ reduction from HOAc in CH3CN by up to 600 mV. The most effective electrocatalyst is the asymmetric 1-PTA species, which promotes H2 formation from HOAc (pKa in CH3CN = 22.6) at −1.4 V in CH3CN/H2O mixtures at the Fe0FeI redox level. Functionalization of the PTA ligand vi...
Delayed emission from recombination of charge-separated pairs on polyfluorene chains in dilute solution

We report the observation of delayed emission (approximately 400 ps with respect to the excitation pulse) from polyfluorene in dilute solution at high excitation intensities. Photoinduced absorption (with initial amplitude superlinearly dependent on the excitation intensity) is also observed with almost instantaneous onset and subpicosecond initial decay, followed by a slow component that decays on the time scale of 200--400 ps. The results are interpreted in terms of generation of charge-separated pairs via dissociation of a higher-energy excited state (created by sequential absorption within the pump pulse) and subsequent recombination of the charged-separated pairs into neutral excitons, which are responsible for the delayed emission. The insensitivity of these features to the concentration and to the use of different solvents confirms their intrachain origin.
Measurement of electrostatic charges and concentration of particles in the freeboard of a fluidized bed

Abstract Measurements of electrostatic charges and charge distribution on solid particles were made in the freeboard of a fluidized bed. A Faraday cage was designed and built for this purpose. With 30 to 55 μm glass beads, 30 μm particles predominate in the freeboard with an air velocity of 5.5 cm/s. The charge distribution ranges from less than 10 to more than 60 × 10 −15 C. The mean charge was shown to vary with 1.4 power of the particle diameter. A cylindrical probe, 21 mm i.d. and 56 mm long, was used to determine particle concentration via charge collection.
PROMOTION OF PLASTID PIGMENT ACCUMULATION IN WATER STRESSED WHEAT LEAF SECTIONS BY HORMONE TREATMENT

Chlorophyll (Chl) and carotenoid accumulations are markedly reduced in detached wheat leaves after 20-hr exposure to light when subjected to mild (-7 bar) osmotic stress prior to illumination. The treatment of N6-benzyladenine (BA) in combination with gibberellic acid (GA) stimulated the recovery of plastid pigment accumulations in mildy stressed detached leaves. The combination treatment of BA plus IAA increased pigment accumulations only to the level stimulated by BA treatment alone. Mild water deficits increased the Chl a/b ratio and reduced the Chl/carotenoid ratio in wheat sections. Growth promoting hormones generally lowered the Chl a/b ratio and increased the Chl/carotenoid ratio in mildly stressed detached leaves. Abscisic acid (ABA) reduced plastid pigment concentrations in greening tissue and increased the Chl a/b ratio while decreasing the Chl/carotenoid ratio. In detached leaves stressed to -14 bars, BA in combination with GA stimulated only partial recovery of the plastid pigment accumulations and improved slightly the Chl a/b and Chl/carotenoid ratios.
Grid-translation beam deflection systems for 5-cm and 30-cm diameter Kaufman thrusters.

A 5-cm grid translation mechanism has been developed capable of 10 deg beam deflection. A 2026-hour endurance test was run at a preset 10 deg deflection angle and an extrapolated lifetime of better than 10,000 hours obtained. Response time data for grid translation are presented. Preliminary results for a 30-cm diameter system are given and results of a theoretical analysis of a dished grid system are discussed.
Dispositional Forgivingness: Development and Construct Validity of the Transgression Narrative Test of Forgivingness (TNTF)

Forgivingness is the disposition to forgive interpersonal transgressions over time and across situations. There is currently no acceptable measure of forgivingness for use in testing theoretical propositions. The authors describe a five-item scenario-based scale, the Transgression Narrative Test of Forgivingness (TNTF). In five studies examining 518 university students from three disparate universities, the authors assess the item and full-scale functioning of the TNTF and its concurrent and 8- week predictive validity relative to trait anger, rumination, neuroticism, agreeableness, and hostility. Test-retest reliability and stability of item locations were both good. Norms are presented by gender, ethnicity, and religious activity. The TNTF is a brief measure of forgivingness that is not theory dependent and is therefore useful in basic and intervention research from a variety of theoretical perspectives.
Problems in identifying an acoustically evoked potential to a single stimulus.

The identification of evoked scalp potentials in man to a single acoustic stimulus such as a word becomes possible by combining several techniques. Either multiple EEG derivations from one subject ...
The Clementine mission —A 10-year perspective

Clementine was a technology demonstration mission jointly sponsored by the Department of Defense (DOD) and NASA that was launched on January 25th, 1994. Its principal objective was to use the Moon, a near-Earth asteroid, and the spacecraft’s Interstage Adapter as targets to demonstrate lightweight sensor performance and several innovative spacecraft systems and technologies. The design, development, and operation of the Clementine spacecraft and ground system was performed by the Naval Research Laboratory. For over two months Clementine mapped the Moon, producing the first multispectral global digital map of the Moon, the first global topographic map, and contributing several other important scientific discoveries, including the possibility of ice at the lunar South Pole. New experiments or schedule modifications were made with minimal constraints, maximizing science return, thus creating a new paradigm for mission operations. Clementine was the first mission known to conduct an in-flight autonomous operations experiment. After leaving the Moon, Clementine suffered an onboard failure that caused cancellation of the asteroid rendezvous. Despite this setback, NASA and the DOD applied the lessons learned from the Clementine mission to later missions. Clementine set the standard against which new small spacecraft missions are commonly measured. More than any other mission, Clementine has the most influence (scientifically, technically, and operationally) on the lunar missions being planned for the next decade.
Towards a Unified Local Area Network Architecture for the United States Air Force

This paper provides an overview of a comnunications system currently being specified by the Air Force's Unified Local Area Network Architecture program (ULANA). The UIANA network, in conjunction with the DoD long haul Defense Data Network (DDN), aims to integrate the Air Force's current mix of heterogeneous computers, communications and operating systems and applications packages into a flexible, survivable, and interoperable backbone for Air Force Information Systems. The following aspects of the ULANA program are described: ?objectives and scope of the ULANA program, ?functions and components of the ULANA system, ?a survivable (through segmentation) signal distribution system ?a unified family of Network Inter face and Interconnect Units, their generic types and interconnection mechanisms over multiple channels, ?a layered protocol architecture which permits communications between diverse devices and application processes associated with them within the ULANA local area network, and ?a distributed network management system. The paper concludes with a discussion of the possible impact of the Unified Local Area Network Architecture on the Air Force distributed information systems and a summary of the architectural principles employed by ULANA.
Viscous effects on hypersonic L/D of three classes of manned spacecraft.

Viscous degradation of hypersonic lift-drag ratio in manned spacecraft, noting free stream Mach and Reynolds numbers
Estimating Recreational User Counts: Corrigendum

In an earlier article in this Journal (Johnston and Tyrrell, henceforth JT), we outline a methodology for estimating the number of visitors to a set of recreational sites, as well as counts of specific visitor groups. The model is designed for combinations of sites characterized by (a) unrestricted recreation from a wide and partially unknown geographic market, (b) individuals who may visit more than one site, and (c) accurate visitation (gate) counts from each site. In our earlier manuscript, we state that the model provides consistent estimates of the total number of individual visitors, based on information embedded in site-level
The residential conservation service in Vermont: An evaluation of program implementation☆

Abstract Criteria developed by Sabotier and Mazmanian (S&M) are used to assess the implementation of a statewide energy conservation program: the Residential Conservation Service as it existed in Vermont for approximately four years. The study draws conclusions concerning the implementation and evaluation of conservation programs. It also indicates some kinds of evaluation settings in which the S&M implementation framework may be especially useful. These include programs in which state officials have considerable discretion in implementing national policy, and also programs in which the “program model” is difficult to test.
Stepping over obstacles: gait patterns of healthy young and old adults

Falls associated with tripping over an obstacle can be devastating to elderly individuals, yet little is known about the strategies used for stepping over obstacles by either old or young adults. The gait of gender-matched groups of 24 young and 24 old healthy adults (mean ages 22 and 71 years) was studied during a 4 m approach to and while stepping over obstacles of 0, 25, 51, or 152 mm height and in level obstacle-free walking. Optoelectronic cameras and recorders were used to record approach and obstacle crossing speeds as well as bilateral lower extremity kinematic parameters that described foot placement and movement trajectories relative to the obstacle. The results showed that age had no effect on minimum swing foot clearance (FC) over an obstacle. For the 25 mm obstacle, mean FC was 64 mm, or approximately three times that used in level gait; FC increased nonlinearly with obstacle height for all subjects. Although no age differences were found in obstacle-free gait, old adults exhibited a significantly more conservative strategy when crossing obstacles, with slower crossing speed, shorter step length, and shorter obstacle-heel strike distance. In addition, the old adults crossed the obstacle so that it was 10% further forward in their obstacle-crossing step. Although all subjects successfully avoided the riskiest form of obstacle contact, tripping, 4/24 healthy old adults stepped on an obstacle, demonstrating an increased risk for obstacle contact with age.
The transitivity of preferences

If you would rather have a vacation in Capri than a red sport car, and if you would rather have the car than a thirty-foot yawl, is it safe to assume that you would prefer the vacation to the boat? This assumption of “transitivity” is often made in theories of behavior, particularly in theories of decision making. But even though transitivity of preferences is a basic assumption of economic theory, several economists maintain that stable intransitive preferences do exist. You might well, they would say, take the yawl, not the vacation. Two experiments designed to test these assumptions show that intransitivity may be explained as a result of random choices among indifferent objects, and that the assumptions of transitivity still hold.
In vitro cell response to differences in poly‐L‐lactide crystallinity

Many different processing techniques are currently being used to produce tissue regeneration devices from polyesters in the polylactide/polyglycolide family. While it is generally well recognized that processing techniques influence bulk mechanical and degradation properties of these materials, the effects on surface properties are relatively less well studied. We thus investigated the effects of processing conditions that are known to change bulk properties, but not composition, on the surface properties of poly-L-lactide (PLLA). Specifically, we investigated the role of bulk crystallinity of PLLA substrates on several physiochemical aspects of the surface and on the attachment, morphology, and differentiated function of cultured primary hepatocytes and growth of 3T3 fibroblasts. We fabricated smooth, clear PLLA films of 13-37% crystallinity. Glancing angle X-ray diffraction indicated that low crystallinity films lacked order in the first 50 A of the surface while relatively high crystallinity films had detectable order in this range. In other aspects, the surfaces of all PLLA substrates appeared identical with XPS, SEM, and advancing contact angle analysis, but contact angle hysteresis was slightly greater for more crystalline films. Although the physicochemical properties of the surfaces appeared almost identical, we observed differences in cell behavior on less crystalline versus more crystalline films. Hepatocytes formed spheroids on all PLLA substrates, but spheroid formation was faster (24-48 H) on crystalline substrates. quantitative image analysis was used to assess the average cell area as a function of time in culture, and our data confirm previous reports that retention of differentiated function is inversely related to cell spreading where function was assessed by P-450 enzyme activity. In addition, the growth rate of 3T3 fibroblasts was lower on crystalline substrates than on amorphous substrates. An important conclusion from this work is that processing techniques that lead to seemingly inconsequential changes in bulk and surface properties of these polymers may influence biological response.
Fitting Multilevel Models With Ordinal Outcomes: Performance of Alternative Specifications and Methods of Estimation

Previous research has compared methods of estimation for multilevel models fit to binary data but there are reasons to believe that the results will not always generalize to the ordinal case. This paper thus evaluates (a) whether and when fitting multilevel linear models to ordinal outcome data is justified and (b) which estimator to employ when instead fitting multilevel cumulative logit models to ordinal data, Maximum Likelihood (ML) or Penalized Quasi-Likelihood (PQL). ML and PQL are compared across variations in sample size, magnitude of variance components, number of outcome categories, and distribution shape. Fitting a multilevel linear model to ordinal outcomes is shown to be inferior in virtually all circumstances. PQL performance improves markedly with the number of ordinal categories, regardless of distribution shape. In contrast to binary data, PQL often performs as well as ML when used with ordinal data. Further, the performance of PQL is typically superior to ML when the data includes a small to moderate number of clusters (i.e., ≤ 50 clusters).
The bulk modulus of covalent random networks

We re-examine the calculation of the bulk modulus of random networks with a variable mean coordination that ranges from down through the phase transition from rigid to floppy that occurs at around . In contrast to previous workers, we use random-network models, rather than depleted diamond lattices, so our results are more relevant to glasses. We find that the bulk modulus behaves in a very similar way to that found previously for depleted diamond lattices, with the bulk modulus going to zero at around with an exponent of 1.4. In the course of this study we came across many examples of transitions between different local minima, especially in networks with a low mean coordination. We discuss and illustrate the nature of these metastable states and show that although there are differences in the local minimum energy associated with these states, the bulk modulus (curvature around the minimum) is essentially independent of which minima the system is in. We show that these nearly degenerate local minima are associated with different local confirmations of very short polymer chains.
The dehydroxylation of chlorite and the formation of topotactic product phases

Single-crystal, X-ray examination of Mg,Fe-rich chlorites that were heated at 650°C for 24 hours in air and have undergone dehydroxylation of the interlayer shows that two product phases result with a topotactic relationship, with the c axis of both phases parallel. One phase (“modified chlorite” or “14-A phase”) has relatively sharp reflections with a 14-A c-axis repeat, indicating that it is well crystallized and maintains the 2:1 layer from the parent. Cell parameters are a = 5.368(1)A, b - 9.297(2)A, c = 14.215(6)A, a = 89.86(3)°, s = 97.15(3)°, γ = 89.98(2)°, and it crystallizes in CĪ symmetry. A structure refinement, details of which will be reported later, indicates that the interlayer consists of two planes, each containing (M + O), where M is the interlayer cation species. These planes show about ±0.5A positional disorder along the [001] direction. There is no evidence for scattering material at z = 0.5 between the 2:1 layers. The second phase in the topotactic relationship is based on a 27-A unit c axis (“27-A phase”). The diffraction data are limited with about 15 diffuse reflections observed, indicating that it is poorly crystallized. The 27-A spacing suggests that both octahedral sheets in the parent chlorite contribute to the formation of this phase. Heating Mg,Fe-rich chlorite powder in a closed system to 550°C, under either reducing or oxidizing conditions, prevents the formation of the 27-A phase. Because the 27-A phase forms in an open system, we infer that water fugacity is an important factor in its formation. Heating experiments involving samples with different polytypes and octahedral “type” (dioctahedral vs trioctahedral) of the 2:1 layer suggests that these two variables are important. However, the results are equivocal, and an ill-defined B-rich chlorite from Madagascar breaks the observed trends for both variations in stacking sequence and octahedral type. However, B-content may be a factor in the transformation also for those chlorites that contain B.
Eight new species of Lauraceae from Ecuador, Peru, and Panama.

Eight new species of Lauraceae from Andean South America and Panama are described and illustrated. Two belong to the genus Cinnamomum Schaeffer, C. lanigerum van der Werff and C. formicarium van der Werff & Lorea-Hernandez, both from Ecuador; one species belongs to Ocotea Aublet, O. pacifica van der Werff, from Ecuador and Colombia; and five belong to Pleurothyrium Nees, P. bilocellatum van der Werff, P. cordatum van der Werff, and P. obscurinerve van der Werff from Ecuador, P. pascoense van der Werff from Peru, and P. triflorum van der Werff from Panama.
A click chemistry approach to identify protein targets of cancer chemopreventive phenethyl isothiocyanate

Here we report the identification of protein targets of chemopreventive phenethyl isothiocyanate (PEITC) via “click” chemistry in the A549 human lung cancer cell line, using a novel alkyne-tagged PEITC which was also found to show potent in vitro anticancer activity.
Incidence and management of marginal ulceration after laparoscopic Roux-Y gastric bypass

Abstract Background Marginal ulceration (MU) is a well-known complication after gastrojejunostomy; however, its incidence has rarely been reported in bariatric studies. We present 16 cases of documented MU after laparoscopic gastric bypass (LGBP) that were successfully treated with proton pump inhibition (PPI). Methods All patients undergoing LGBP from October 2002 to August 2005 were entered into a prospective, longitudinal database. All patients who subsequently presented with MU were analyzed. MU was diagnosed when patients presented postoperatively with mid-epigastric pain and/or upper gastrointestinal bleeding that responded to PPI or endoscopic intervention. Analysis of variance and Student's t test were used for the statistical analyses. Results MU was diagnosed in 16 (4%) of 347 patients in whom LGBP was performed. An additional 10 patients had symptoms suggestive of MU, which raised the incidence as great as 7%. Of the 26 patients, 18 were women and 8 were men (age range 23–53 years), with a preoperative body mass index 37.1–63.9 kg/m 2 , similar to that of the patients who did not develop MU. Compared with the patients who did not develop MU, the operative times were longer in the MU group (180.5 versus 140.4 minutes, P P = 0.006). Conclusion We report 16 documented cases of MU occurring after LGBP. This underreported complication can be successfully treated with PPI, although MU complicated by gastrogastric fistula may require operative intervention. The institution of routine PPI therapy after LGBP lowered the short-term incidence of MU at our institution. Additionally, we recommend that all patients who undergo LGBP be given prophylactic PPI therapy postoperatively.
REVISITING THE t TEST ON RANKS AS AN ALTERNATIVE TO THE WILCOXON RANK-SUM TEST '

Summary.-In comparison with the Student t test, the test on the ranks of scores has been shown to be slightly less powerful than the Wilcoxon Rank-Sum test conducted on the original scores For real smooth and symmetric data sets because it does not provide a correction for ties or continuity. Here it is demonstrated that the t test on ranks is nonetheless superior to the usual t test for real data that are skewed or otherwise severely nonnormally distributed. The advice to use the nonparametric Wilcoxon Rank-sum test in applied data analysis is based on studies of its statistical power in comparison with the parametric t test on data sampled from theoretical nonnormal distributions (Blair & Higgins, 1980a, 1980b). The Wilcoxon test has been - shown to be as much as three or four times more powerful than the t test when data are highly skewed or come from populations with heavy tails (Sawdowsky & Blair, 1992). When data are normally hstributed, the Wilcoxon test is typically only slightly less powerful (e.g., about 0.02) than its parametric counterpart. Therefore, there is much to gain if the population is nonnormdy distributed and little to lose in using the Wilcoxon test when the data come from a normal distribution. Given the prevalence of nonnormality in applied psychological and educational data (Ahcceri, 1989), researchers should give serious consideration to performing the nonparametric Wilcoxon test instead of the classic t test. Zirnmerman and Zurnbo (199O),.among others, noted that an analog to the Wilcoxon test can easily be computed by simply ranking the original scores, and then applying the t test on those ranks. This technique also has the advantage of using the critical values of the t test, which are found in many textbooks and computer statistics packages. They referred to this procedure as being alpha equivalent, meaning that whatever statistical conclusion would be obtained by the Wilcoxon Rank-Sum test on the original scores WLU be the same as that obtained by computing the t test on the ranks of the original scores. Sadowsky and Brown (1991) investigated the comparative power properties of the two procedures for a real data set identified by Micceri (1989)
Letting the good times roll: A theory of voter inference and experimental evidence

This paper examines inference and attribution in a simple and ubiquitous strategic situation: a voter is faced with discerning whether a leader worked on his or her behalf after observing an informative, but noisy signal about the leader's performance. We characterize perfect Bayesian equilibria, quantal response equilibria (QRE), and provide a simple model of a heuristic-based approach, referred to as strategic naivete, within a wide class of such environments. We also discuss experiments conducted to examine human behavior within such an environment. While it is clear that the observed behavior is inconsistent with perfect Bayesian equilibrium, distinguishing between QRE and strategic naivete will require further work. We conclude with a discussion of the broader implications of probabilistic and/or heuristic-based attribution processes for electoral politics and political economy.
Integrated Sensors for Charged-Particle Imaging Using Per-Pixel Correlated Double Sampling

Monolithic CMOS cameras for direct imaging in electron microscopy and other radiation imaging applications have been developed and have been used to capture images with high signal to noise and resolution. Based on CMOS Active Pixel Sensor (APS) technology, the arrays use an 8 to 20 mum epitaxial layer that acts as a thicker sensitive region for the liberation and collection of ionization electrons resulting from impinging charged particles. This results in a 100% fill factor and a far larger signal per incident charged particle than a typical CMOS photodiode could provide. The per-pixel CDS scheme discussed in this paper has demonstrated reductions in kT/C noise by a factor of four, to 11 electrons RMS at room temperature. The CDS scheme requires only one read instead of the two reads plus pre- and post-integration subtraction required by traditional CDS, and is hence faster than alternate schemes. In addition, the test device was used in the observation of Random Telegraph Signal noise (RTS) in small-capacitance pixels under different V gs conditions.
Multivalent scaffolds induce galectin-3 aggregation into nanoparticles

Galectin-3 meditates cell surface glycoprotein clustering, cross linking, and lattice formation. In cancer biology, galectin-3 has been reported to play a role in aggregation processes that lead to tumor embolization and survival. Here, we show that lactose-functionalized dendrimers interact with galectin-3 in a multivalent fashion to form aggregates. The glycodendrimer–galectin aggregates were characterized by dynamic light scattering and fluorescence microscopy methodologies and were found to be discrete particles that increased in size as the dendrimer generation was increased. These results show that nucleated aggregation of galectin-3 can be regulated by the nucleating polymer and provide insights that improve the general understanding of the binding and function of sugar-binding proteins.
White cell reduction in platelet concentrates and packed red cells by filtration: a multicenter clinical trial. The Trap Study Group.

BACKGROUND: Most previous studies on white cell (WBC) reduction by filtration have been small-scale studies conducted under tightly controlled laboratory conditions. Their results would be the ideal, rather than what might be expected during routine operation. STUDY DESIGN AND METHODS: To obtain information on routine filtration of blood components, data have been collected from a large-scale, ongoing, multicenter clinical trial designed to determine the effectiveness of WBC reduction in or ultraviolet B radiation of platelet concentrates before transfusion in preventing platelet alloimmunization and platelet transfusion refractoriness. The WBC content of blood components both before and after filtration was determined by automated cell counters and a manual propidium iodide-staining method, respectively. Platelet and red cell losses during filtration were measured. RESULTS: The average platelet losses after filtration were 24 +/− 15 percent and 20 +/− 9 percent for apheresis platelets and pooled platelets, respectively. The frequencies at which filtered platelet concentrates contained high levels of residual WBCs (> 5 × 10(6)) were 7 percent and 5 percent for apheresis platelets and pooled platelets, respectively. Further analysis of the platelet filtration data showed that greater numbers of total initial WBCs in the pooled platelets were associated with increased percentages of filtration failure (> 5 × 10(6) residual WBCs). For packed red cells, the average losses during filtration were 23 +/− 4 percent and 15 +/− 3 percent for CPDA-1 units and Adsol units, respectively. The frequencies at which filtered red cells contained > 5 × 10(6) residual WBCs were 2.7 percent for one type of filter and 0.3 percent for another type of filter. CONCLUSION: There were significant losses of platelets during filtration, which could add to the costs of WBC reduction and lead to possible increases in donor exposures. Filtration failures still occurred, despite careful observation of the standard filtration procedures. The number of total WBCs in pooled platelets before filtration has been identified as an important factor in determining the success of WBC reduction.