cssi/SciSciGPT-SciSciNet huggingface dataset:
Free Conducting Particles in a Coaxial Compressed-Gas-Insulated System

The effect of free conducting particles (FCPs) on the voltage-insulating performance of a short length of transmission line was quantitatively studied over the pressure range 0 to 300 psig for nitrogen and 0 to 125 psig for SF6. The FCPs were selected aluminum filings deliberately inserted into the concentric cylindrical (3"×10" dia.) electrode system. DC voltages of either polarity were produced by a Van de Graaff generator. The observed forms of interelectrode current included intermittent pulses or 'bursts', 'fireflies', steady corona, and sparks. Up to five-fold reductions in the current-onset voltage insulating strength resulted from the introduction of FCPs. For pressures up to 75 psig the sparking voltage in SF6 was 4 to 5 times higher than the sparking value in nitrogen. An electrostatic particle trap proved effective in reducing FCP-caused discharges. The dynamic equilibrium mechanism of 'fireflies' was studied in detail.
Optimal ordering, discounting, and pricing in the single-period problem

Abstract The single-period problem (SPP), also known as the newsboy or newsvendor problem, is to find the order quantity which maximizes the expected profit in a single-period probabilistic demand framework. Previous extensions to the SPP include, in separate models, the simultaneous determination of the optimal price and quantity when demand is price-dependent, and the determination of the optimal order quantity when progressive discounts with preset prices are used to sell excess inventory. In this paper, we extend the SPP to the case in which demand is price-dependent and multiple discounts with prices under the control of the newsvendor are used to sell excess inventory. First, we develop two algorithms for determining the optimal number of discounts under fixed discounting cost for a given order quantity and realization of demand. Then, we identify the optimal order quantity before any demand is realized. We also analyze the joint determination of the order quantity and initial price. We illustrate the models and provide some insights using numerical examples.
Field Evaluation Of Radiographic Phototimers

A protocol for acceptance testing and performance monitoring of radiographic phototimers is described, together with results obtained during application of the protocol to evaluation of the response characteristics of phototimers on two new x-ray generators.
Disciplinary Practices and Perceptions of School Safety

Abstract This study of a sample of 4,044 eighth grade students taken from the National Educational Longitudinal Study of 1988 (NELS:88) was designed to examine the contribution that zero-tolerance disciplinary policies, school climate, parents' and teachers' perceptions of disciplinary climate make to students' perceptions of the school's disciplinary climate. Additionally, this study examined whether school location (i.e., urban and suburban) and school type (i.e., public and private) are associated with differences in disciplinary practices, perceptions of school discipline and school climate. Zero-tolerance disciplinary policies were found to be both directly and indirectly associated with students' perceptions of fewer discipline problems. Additionally, private schools can be characterized as having: tougher discipline policies; less teacher concern about school discipline; more student concern about school discipline; and more positive perceptions of school climate among administrators and parents th...
Comparative structural analysis and kinetic properties of lactate dehydrogenases from the four species of human malarial parasites.

Parasite lactate dehydrogenase (pLDH) is a potential drug target for new antimalarials owing to parasite dependence on glycolysis for ATP production. The pLDH from all four species of human malarial parasites were cloned, expressed, and analyzed for structural and kinetic properties that might be exploited for drug development. pLDH from Plasmodium vivax, malariae, and ovale exhibit 90−92% identity to pLDH from Plasmodium falciparum. Catalytic residues are identical. Resides I250 and T246, conserved in most LDH, are replaced by proline in all pLDH. The pLDH contain the same five-amino acid insert (DKEWN) in the substrate specificity loops. Within the cofactor site, pLDH from P. falciparum and P. malariae are identical, while pLDH from P. vivax and P. ovale have one substitution. Homology modeling of pLDH from P. vivax, ovale, and malariae with the crystal structure of pLDH from P. falciparum gave nearly identical structures. Nevertheless, the kinetic properties and sensitivities to inhibitors targeted to ...
Transgenderism, Locality, and the Miss Galaxy beauty pageant in Tonga

vides an escape route from local dynamics of social exclusion and poverty, but it also potentially offers mainstream persons a pretext to marginalize transgendered persons from their local groundings. Privileged transgendered persons are less vulnerable to these dynamics of exclusion and use tokens of translocality to assert their social standing vis-a-vis both underprivileged transgendered persons and society at large. [transgenderism, beauty pageants, locality, globalization, resistance, language use, Tonga] Every year at the conclusion of the month-long Heilala Festival in Nuku'alofa, Tonga (Western Polynesia), "men who act like women" organize the Miss Galaxy beauty pageant-an extravagant and glamorous show of fashions, bodies, inventiveness, fantasy, and humor. Since its inception in the early 1990s, Miss Galaxy has become increasingly spectacular, assertive, and innovative. Held in one of the most prominent public venues in the country, the pageant is the subject of a considerable
Tackling strategy management

Abstract Managing strategies in a one-man business is second nature to the entrepreneur. Strategic coordination becomes much more problematic as the company grows. In today's large multi-nationals, their size constantly threatens strategic lethargy and inertia. Only those companies which can manage their business strategies effectively in all levels of the enterprise are likely to survive and prosper against the competition. This paper seeks to describe how one manufacturing enterprise, as part of a very large marketing oriented multi-national, sets out to tackle this challenge.
Fabrication of Ceramic Microstructures via Microcasting of Nanoparticulate Slurry

Fabrication of microstructures has been the subject of considerable attention in recent years. Techniques such as surface silicon micromachining and bulk silicon etch have emerged as practical methods for thin microstructures and processes such as LIGA (an acronym for the German words for lithography, electrodeposition, and molding) are being used to produce high aspect ratio structures from a limited set of electroformable metals and polymers. As microsystem technologies and application prospects continue to grow, it is of interest and much practical value to expand the material choices for LIGA-scale microstructures to ceramics and a broader class of metals. To this end, this paper investigates a new technique for the fabrication of high aspect ratio ceramic or metal microparts. This technique is based on capillary-driven microcasting and curing of an epoxy-based metallic or ceramic nanoparticulate slurry into a sacrificial plastic mold produced by microinjection molding. The cured preform is subsequently heated to remove the organic phase and to sinter the particulate ceramic or metallic phase. The fabrication process is discussed in the paper along with illustration of example microparts produced using the process. A theoretical model of the fluid flow during the microcasting process is developed and validated with experimental data from the fabrication of rectangular rib sections.
Mixing and contacting models for fluidized beds

Parameters of the two-phase model for mixing in fluidized beds were evaluated from a large amount of available literature data. The dense phase dispersion coefficients and the cross flow, or interphase transfer, coefficients, based on the consistent model calculations, were correlated with operating conditions. A strong effect of bed length-to-diameter ratio was found for the dense phase mixing but not for the cross flow. On the basis of the given kinetics information with the mathematical model parameter correlations, some chemical reactor conversions from the literature were predicted by a priori calculations.
Temporal intraspeech masking of plosive bursts: effects of hearing loss and frequency shaping.

Purpose The purposes were (a) to compare masking of consonant bursts by adjacent vowels for listeners with and without hearing loss and (b) to determine the extent to which the temporal intraspeech...
Atomic Force Microscopy-based repeatable surface nanomachining for nanochannels on bare silicon substrates

The Atomic Force Microscopy (AFM)-based repeatable nanomachining for nanochannels on bare silicon surface is investigated experimentally. A relationship between the normal force applied on the AFM cantilever and the channel depth is established. Thus, current results can be regarded as the calibration reference in order to accurately predict the nanochannel depth for additional nanotechnology related applications. An accurate prediction of the depth is not only for accuracy and efficiency, but also to prevent a costly diamond tip from unnecessary wearing out. Furthermore, the experimental results also reveal that the fabrication procedure is repeatable, and multiple scratching will further increase the depth of the nanochannel.
An episomal expression vector for screening mutant gene libraries in Pichia pastoris.

Screening mutant gene libraries for isolating improved enzyme variants is a powerful technique that benefits from effective and reliable biological expression systems. Pichia pastoris is a very useful organism to express proteins that are inactive in other hosts such as Escherichia coli and Saccharomyces cerevisiae. However, most P. pastoris expression plasmids are designed to integrate into the host chromosome and hence are not as amenable to high-throughput screening projects. We have designed a P. pastoris expression vector, pBGP1, incorporating an autonomous replication sequence that allows the plasmid to exist as an episomal element. This vector contains the α-factor signal sequence to direct secretion of the mutant enzymes. Expression of the genes is driven by the constitutive GAP promoter, thus eliminating the need for timed or cell density-specific inductions. The pBGP1 plasmid was used to screen a xylanase gene library to isolate higher activity mutants.
Design and Fabrication of Miniature Objective Lens for Three Part White Blood Cell Differential Measurements

Three-part differential white blood cell counts are used for disease diagnosis and monitoring at the point-of-care. A low-cost, miniature fluorescent microscope was fabricated for quantification of lymphocytes, granulocytes, and monocytes in whole blood samples.
Cardiac troponin T and myocardial injury during routine cardiac catheterisation in children.

Abstract Background: This study aims to investigate whether intracardiac catheterization produces myocardial damage on pediatric heart. Methods: Five blood samples were collected (basal, immediate post procedure, at 4, 12 and 24 h after the procedure) for troponin T and creatine kinase MB (CKMB) from 48 consecutive patients (age: 5.34±6.03 years). The effect of age, duration of procedure, pulmonary hypertension, cyanosis, and medication taken for congestive heart failure on the levels of troponin T and CKMB were sought. Results: The increase in CKMB (basal CKMB: 3.93±3.70 ng/ml; peak CKMB: 8.68±10.89 ng/ml; P P 25 mmHg), longer procedure time (>30 min), and patients taking anti-congestive heart failure therapy had significantly higher levels of CKMB and troponin ( P >0.05). Conclusion: All patients undergoing cardiac catheterization are under risk of myocardial injury, and younger patients with pulmonary hypertension and especially with compensated cardiac failure have increased risk of myocardial damage, and need to be handled carefully.
Pulmonary Resistance in Acquired Heart Disease

Disproportionately high pulmonary artery pressures and pulmonary vascular resistance in acquired heart disease, particularly mitral stenosis, have been repeatedly observed. Seventeen patients with pulmonary hypertension secondary to elevated left atrial pressure have been studied by the method of temporary unilateral pulmonary artery occlusion: Resistances calculated before and after occlusion showed no change in most cases. The data show that despite very high initial resistance, increase in flow in the lung can occur with rapid reduction in resistance. It is suggested that "tone" of the pulmonary vasculature is operative even at very high pressure levels.
Ionic Polymerization of α, α -Disubstituted Vinyl Monomers

Abstract Alkyl α-chloroacrylates and p-substituted α-methylstyrenes were investigated for the effect of polymerization conditions on tacticity, molecular weight, and distribution, and for the relationship between tacticity, glass temperature, and crystalline properties.
PVM‐AMBER: A parallel implementation of the AMBER molecular mechanics package for workstation clusters

A parallel version of the popular molecular mechanics package AMBER suitable for execution on workstation clusters has been developed. Computer-intensive portions of molecular dynamics or free-energy perturbation computations, such as nonbonded pair list generation or calculation of nonbonded energies and forces, are distributed across a collection of Unix workstations linked by Ethernet or FDDI connections. This parallel implementation utilizes the message-passing software PVM (Parallel Virtual Machine) from Oak Ridge National Laboratory to coordinate data exchange and processor synchronization. Test simulations performed for solvated peptide, protein, and lipid bilayer systems indicate that reasonable parallel efficiency (70–90%) and computational speedup (2–5 × serial computer runtimes) can be achieved with small workstation clusters (typically six to eight machines) for typical biomolecular simulation problems. PVM-AMBER is also easily and rapidly portable to different hardware platforms due to the availability of PVM for numerous computers. The current version of PVM-AMBER has been tested successfully on Silicon Graphics, IBM RS6000, DEC ALPHA, and HP 735 workstation clusters and heterogeneous clusters of these machines, as well as on CRAY T3D and Kendall Square KSR2 parallel supercomputers. Thus, PVM-AMBER provides a simple and cost-effective mechanism for parallel molecular dynamics simulations on readily available hardware platforms. Factors that affect the efficiency of this approach are discussed. © 1995 by John Wiley & Sons, Inc.
Weak matching rules for quasicrystals

Weak matching rules for a quasicrystalline tiling are local rules that ensure that fluctuations in “perp-space” are uniformly bounded. It is shown here that weak matching rules exist forN-fold symmetric tilings, whereN is any integer not divisible by four. The result suggests that, contrary to previous indications, quasicrystalline ground states are not confined to those symmetries for which the incommensurate ratios of wavevectors are quadratic irrationals. An explicit method of constructing weak matching rules forN-fold symmetric tilings in two dimensions is presented. It is shown that the generalization of the construction yields weak matching rules in the case of icosahedral symmetry as well.
Nonmarital Fertility, Family Structure, and the Early School Achievement of Young Children From Different Race/Ethnic and Immigration Groups

Working from a life course perspective, this study examined the links between mothers' fertility and relationship statuses and children's early school achievement and how these links varied by race/ethnicity and immigration status. Analyses of nationally representative data from the Early Childhood Longitudinal Study–Kindergarten Cohort revealed that children born to unmarried women scored lower than children of married women on math tests in kindergarten and first grade. This pattern was most attributable to associated differences in family income and parent education, and it was moderated by women's marital and relationship statuses after having their children. Evidence also suggested that the academic risks of some family structure pattern relative to continuously married parents might have been more pronounced for White children.
Strain distributions in the cold drawing of cylindrical polymeric bars using photoplasticity

Full-field strain distributions in the cold drawing of polycarbonate cylindrical bars are obtained using photoplasticity at three stages of neck propagation. The results indicate that the radial and circumferential strains are almost identical. The strain distributions in the seemingly straight (drawn) portion are nonuiform. The locations of maximum and minimum strains shift when elongations increase. Various sensitivity studies are also reported.
Strömgren Hβ-photometry of stars in dark clouds

We present uvbyβ photometry of 64 stars in 6 small dark clouds. From the photometry we infer approximate spectral types of the observed stars and derive distances and color excesses for each of them. We further derive new distance estimates to some of the globules based on the distances of individual stars possibly included in their peripheries. For clouds where sufficient target stars are available (CB3, CB52, and CB54), a clear trend of increasing linear polarization (as measured by Sen et al. 2000) with extinction is observed. We also find excellent correlation between polarization and extinction for the entire sample. The location of the stars on the polarization-extinction diagram is consistent with that for field stars found by Serkowski et al. (1975). The relation between polarization and extinction evident for the stars of our sample suggests perfect grain alignment and constant grain properties along each line of sight (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Design of optimal cancer chemotherapy using a continuous-time state model of cell kinetics

Abstract A continuous bilinear model in state space is used to describe the cell kinetics of a tumor-cell population under the effects of chemotherapy. Firstly, the time-course behavior of a Chinese-hamster-ovary (CHO) cell population is simulated to demonstrate the utility of the model. Then, an optimal strategy for cancer treatment is derived, based on the need to balance the effects on both cancerous and normal tissues. The performance index minimized is the sum of the weighted tumor population and the weighted total drug dosage. The optimization problem has resulted in a two-point boundary-value problem (TPBVP) with a bang-bang control policy, which is solved by the switching-time variation method (STVM). Computer simulation of CHO cells is also carried out as a numerical example of determining optimal cancer chemotherapy.
Form Recognition Using Moment Invariants for Three Dimensional Perspective Transformations

The invariant recognition of forms is important for many tasks. The purpose of this paper is to consider algebraic and moment invariants for perspective transformations. These are important because every lens system induces a perspective transformation. The approach consists of considering the non-linear perspective transformation in a higher dimensional, homogenous space. In homogeneous space the perspective transformation is linear and algebraic invariant theory may be used to determine absolute algebraic and moment invariants. The cross ratio is a well known perspective invariant. New moment invariants corresponding to the perspective transformation are derived. Examples are presented to demonstrate the theoretical approach. The significance of this work lies in the importance of invariant recognition for both human and machine vision.© (1987) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Cell Size Control in Bacteria

Like eukaryotes, bacteria must coordinate division with growth to ensure cells are the appropriate size for a given environmental condition or developmental fate. As single-celled organisms, nutrient availability is one of the strongest influences on bacterial cell size. Classic physiological experiments conducted over four decades ago first demonstrated that cell size is directly correlated with nutrient source and growth rate in the Gram-negative bacterium Salmonella typhimurium . This observation subsequently served as the basis for studies revealing a role for cell size in cell cycle progression in a closely related organism, Escherichia coli . More recently, the development of powerful genetic, molecular, and imaging tools has allowed us to identify and characterize the nutrient-dependent pathway responsible for coordinating cell division and cell size with growth rate in the Gram-positive model organism Bacillus subtilis . Here, we discuss the role of cell size in bacterial growth and development and propose a broadly applicable model for cell size control in this important and highly divergent domain of life.
Combination thyroplasty and the “twisted larynx:” combined type IV and type I thyroplasty for superior laryngeal nerve weakness

Vocal cord medialization through Isshiki type I thyroplasty is part of the standard approach for patients with unilateral vocal cord immobility secondary to recurrent laryngeal nerve paralysis. However, several other modalities have been used to treat the symptomatic "twisted" larynx caused by unilateral superior laryngeal nerve weakness. The Isshiki type IV thyroplasty (cricothyroid approximation) specifically addresses cricothyroid muscle weakness, but, canine studies at the Mayo Clinic demonstrated a trend toward decreased acoustic power and sound intensity with simulated cricothyroid activity. Thus it is reasoned that addition of an ipsilateral type I thyroplasty should help compensate for this power loss. Using videostroboscopic and acoustic analysis, 9 patients with unilateral superor laryngeal nerve weakness were treated with combination type IV and type I thyroplasty. Subjective dysphonia and objective visual and acoustic measurements revealed postoperative improvement in most patients. The combination type IV and type I thyroplasty is recommended for surgical treatment of patients with superior laryngeal nerve weakness, because it addresses cricothyroid muscle weakness without compromising vocal power.
Synchronized phasor measurements in power systems

The use of time synchronizing techniques, coupled with the computer-based measurement technique, to measure phasors and phase angle differences in real time is reviewed, and phasor measurement units are discussed. Many of the research projects concerned with applications of synchronized phasor measurements are described. These include measuring the frequency and magnitude of phasor, state estimation, instability prediction, adaptive relaying, and improved control. >
trans-acting requirements for replication of Epstein-Barr virus ori-Lyt.

Abstract Epstein-Barr virus (EBV) utilizes a completely different mode of DNA replication during the lytic cycle than that employed during latency. The latency origin of replication, ori-P, which functions in the replication of the latent episomal form of the EBV genome, requires only a single virally encoded protein, EBNA-1, for its activity. During the lytic cycle, a separate origin, ori-Lyt, is utilized. Relatively little is known about the trans-acting proteins involved in ori-Lyt replication. We established a cotransfection-replication assay to identify EBV genes whose products are required for replication of ori-Lyt. In this assay, a BamHI-H plasmid containing ori-Lyt was replicated in Vero cells cotransfected with the BamHI-H target, the three EBV lytic-cycle transactivators Zta, Rta, and Mta, and the EBV genome provided in the form of a set of six overlapping cosmid clones. By removing individual cosmids from the cotransfection mixture, we found that only three of the six cosmids were necessary for ori-Lyt replication. Subcloning of the essential cosmids led to the identification of six EBV genes that encode replication proteins. These genes and their functions (either known or predicted on the basis of sequence comparison with herpes simplex virus) are BALF5, the DNA polymerase; BALF2, the single-stranded DNA-binding protein homolog; BMRF1, the DNA polymerase processivity factor; BSLF1 and BBLF4, the primase and helicase homologs; and BBLF2/3, a potential homolog of the third component of the helicase-primase complex. In addition, ori-Lyt replication in this cotransfection assay was also dependent on one or more genes provided by the EBV SalI-F fragment and on the three lytic-cycle transactivators Zta, Rta, and Mta.
Measurement of carrier envelope offset frequency for a 10 GHz etalon-stabilized semiconductor optical frequency comb

We report Carrier Envelope Offset (CEO) frequency measurements of a 10 GHz harmonically mode-locked, Fabry-Perot etalon-stabilized, semiconductor optical frequency comb source. A modified multi-heterodyne mixing technique with a reference frequency comb was utilized for the measurement. Also, preliminary results from an attempt at f-2f self-referencing measurement are presented. The CEO frequency was found to be ~1.47 GHz for the particular etalon that was used.
Change agents at work: Lessons from Siemens Nixdorf

This paper describes a major Change Agent Programme conducted by Siemens Nixdorf (and later Siemens AG). This programme was part of a larger, sophisticated culture change initiative. Details of the programme are provided and the benefits accruing to the company are carefully assessed. It was found that impact should be considered at the levels of (a) the participant, (b) the business unit and (c) the corporation and that evaluation requires a longitudinal perspective. A number of lessons are extracted from the analysis – the requirement for serious senior management commitment, the creation of realistic programme expectations, providing a road map for post-programme implementation, and so on. Finally, recommendations are made for future work on this very important topic.
Lymphatic function, lymphangiogenesis, and cancer metastasis

The lymphatic system serves as the primary route for the metastasis of many cancers and the extent of lymph node involvement is the most important indicator of tumor aggressiveness. Despite the apparent importance of the lymphatic vessels for tumor dissemination, it has remained unclear whether activation of lymphatic endothelial cells may affect tumor progression and metastasis and the molecular mechanisms of lymphangiogenesis are just beginning to be elucidated. This overview describes the unique structural and functional characteristics of the lymphatic vessels that render them particularly suitable for invasion by tumor cells and for their efficient transport to lymph nodes. Recent evidence indicates occurrence of tumor lymphangiogenesis and its correlation with metastasis. Molecular regulation of tumor lymphangiogenesis, its significance for tumor metastasis, and implications for cancer therapy are discussed.
Economic Reform and Public Opinion in Peru, 1990-1995

Even if they are confident that prosperity lies just over the horizon, politicians who embark on promarket reforms know they are in for some stormy weather. How will they fare in voters' eyes once the pain is felt? Will voters inevitably turn against politicians who impose painful measures without an electoral mandate to do so? The story of economic reform and public opinion in Peru under Alberto Fujimori (1990-1995) poses just these questions. The author uses monthly public opinion polls and monthly economic data to analyze the impact of economic changes during Fujimori's reform program on opinions of the reforms and the president. The author finds that Limenos withdrew support from the program and the president when employment fell and inflation rose, responses consistent with the findings of the economic voting literature. But when real wages fell, they became optimistic about the future and more likely to support reforms and the government.
The Lords of Caesarea in the Period of the Crusades

CAESAREA in Palestine, located on the coast about midway between Haifa and Jaffa, was one of the first important coastal ports to be captured by the crusaders after the First Crusade, being taken by Baldwin I on May 1, 1101.1 It was granted as a fief to Eustache Grenier, probably between 1105, when he first appears in Palestitie, and 1110, when he is first found as lord of Caesarea.2 He retained his fief of Caesarea when he was later granted that of Sidon, and throughout his lifetime the two fiefs were part of a single seigneury. At Eustache's death in 1123 his fiefs were divided between his twin sons, Sidon going to Eustache and Caesarea to Gautier.3 Thereafter Caesarea was an arriere fief dependent on Sidon, with a quota of 25 knights, rights of 'cou-rt, coins et justice' and a burgess court at Caesarea.4 It included besides the city of Caesarea, the important towns of Chaco (Kakoun), laMerle (Tantourah), the strong fortress of Chateau Pelerin (Athlit), several lesser castles and some forty-five casalia.6 The lords of Caesarea may have been at one time the suzerains of the fief of Bethsan, which itself owed 15 knights service, and was one of the more important arriere fiefs.6 The genealogy of the lords of Caesarea given in the Lignages d'Outremer, chapters xix and xixbis (Assises de J&rusalem, ii, 456-457) and by Rey in his edition of DuCange, Les Families d'Outremer,7 is somewhat confused and inaccurate, so that a new study of this family seemed necessary.
Time thresholds for increments and decrements in luminance.

Time thresholds, i.e., the minimal durations necessary to just detect a change in brightness, were measured for light increments and decrements of a 1° test spot centered on a background of 20°. Background luminance varied from −1 to 3 log td and retinal eccentricity from 0° to 50°. Step size ranged from 0.04 to 1.5 log units and was the same in absolute units for both directions. Two types of stimuli were used: Type A, in which increments and decrements emerge from the same uniform background, and Type B, in which increments are the same as in Type A but decrements consist of a brief interruption of the test spot. Type A stimulation resulted in similar time thresholds for increments and decrements or, under some conditions, slightly shorter decrement thresholds. Type B stimulation resulted in similar thresholds for foveal vision. However, with increasing step size, decreasing background luminance, and increasing eccentricity, the time threshold for the decrement progressively exceeded that for the increment (up to 80 msec). This difference is attributed to different rise and fall times of the photoreceptor response as well as to Troxler’s effect.
Evolution of venom delivery structures in madtom catfishes (Siluriformes: Ictaluridae)

The use of venom to subdue prey or deter predators has evolved multiple times in numerous animal lineages. Catfishes represent one of the most easily recognized, but least studied groups of venomous fishes. Venom glands surround spines on the dorsal and pectoral fins that serve as venom delivery structures. Species of madtom catfishes in the genus Noturus were found to each have one of four venom delivery morphologies: (1) smooth spine with no venom gland; (2) smooth spine with venom gland associated with shaft of spine; (3) serrated spine with venom gland associated with shaft of spine; and (4) serrated spine with venom gland associated with shaft of spine and posterior serrations. Analyses accounting for the phylogenetic history of Noturus species suggest that a serrated pectoral spine with a venom gland is the ancestral condition for the genus. The presence of serrations and a venom gland have been largely conserved among Noturus species, but sting morphology has changed at least five times within the genus. Four of these changes have resulted in a loss of morphological complexity, including the loss of posterior serrations, loss of venom glands associated with the posterior serrations, and one complete loss of the venom gland. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 115–129.
Spina Bifida Research Resource: Study design and participant characteristics†

BACKGROUND: Myelomeningocele is a common serious malformation. In the majority of affected individuals, it is believed to be nonsyndromic and determined by the effects of multiple genetic and nongenetic factors. METHODS: The Spina Bifida Research Resource (SBRR) is an ongoing, family-based study, designed to identify maternal and embryonic genes related to myelomeningocele. Families that include at least one individual with myelomeningocele are eligible to participate in the SBRR. Recruitment into the SBRR has occurred in two phases. Descriptive analyses were undertaken to characterize the case individuals enrolled in Phase 1. In addition, the characteristics of subgroups of case individuals, defined by lesion level, were compared. RESULTS: During Phase 1, 671 families including 683 case individuals were enrolled. Families in which the case individual(s) were known or suspected to have a recognized pattern of malformations and families that did not complete the study interview were excluded from the present analyses. The case individuals in the remaining families (n = 534) were predominantly female (53%) and non-Hispanic Caucasian (87%), and in the majority (74%) the highest level of the lesion was in the lumbar region. Differences in the characteristics of the case individuals with lumbar and thoracic level lesions were detected. CONCLUSIONS: This article provides details regarding study design, recruitment, and data collection, and the characteristics of the SBRR Phase 1 study population. The data available from the SBRR, in combination with a rapidly evolving understanding of the variation within the human genome, provide an unprecedented opportunity to explore the genetic contribution to myelomeningocele. Birth Defects Research (Part A) 2008. © 2008 Wiley-Liss, Inc.
Mutations in the TΨC Loop of E. coli tRNALys,3 Have Varied Effects on In Trans Complementation of HIV-1 Replication

Background: Human immunodeficiency virus (HIV-1) exclusively selects and utilizes tRNALys,3 as the primer for initiation of reverse transcription. Several elements within the TΨC stem loop of tRNA Lys,3 are postulated to be important for selection and use in reverse transcription. The posttranscriptional modification at nucleotide 58 could play a role during plus-strand synthesis to stop reverse transcriptase from re-copying the tRNA primer. Nucleotides 53 and 54 within the TΨC stem loop of the tRNA have been shown to be important to form the complex between tRNA and the HIV-1 viral genome during initiation of reverse transcription. Results: To further delineate the features of the TΨC stem loop of tRNA Lys,3 in reverse transcription, we have developed a complementation system in which E. coli tRNALys,3 is provided in trans to an HIV-1 genome in which the PBS is complementary to this tRNA. Successful selection and use of E. coli tRNA Lys,3 results in the production of infectious virus. We have used this single round infectious system to ascertain the effects that different mutants in the TΨC stem loop of tRNALys,3 have on complementation. Mutants were designed within the TΨC loop (nucleotide 58) and within the stem and loop of the TΨC loop (nucleotides 53 and 54). Analysis of the expression of E. coli tRNA Lys,3 mutants revealed differences in the capacity for aminoacylation, which is an indication of intracellular stability of the tRNA. Alteration of nucleotide 58 from A to U (A58U), T54G and TG5453CC all resulted in tRNALys,3 that was aminoacylated when expressed in cells, while a T54C mutation resulted in a tRNALys,3 that was not aminoacylated. Both the A58U and T54G mutated tRNA Lys,3 complemented HIV-1 replication similar to wild type E. coli tRNA Lys,3 . In contrast, the TG5453CC tRNA Lys,3 mutant did not complement replication. Conclusion: The results demonstrate that post-transcriptional modification of nucleotide 58 in tRNALys,3 is not essential for HIV-1 reverse transcription. In contrast, nucleotides 53 and 54 of tRNA Lys,3 are important for aminoacylation and selection and use of the tRNA Lys,3 in reverse transcription.
O RENASCIMENTO DO RULE OF LAW

Nenhum de nos podera participar de um debate de politica externa hoje em dia sem que alguem proponha o Estado de Direito (rule of law) como uma solucao para um problema ou outro. O Estado de Direito e inegavelmente importante para termos sociedades pacificas, livres e prosperas, mas nao e um problema de rapida e simples solucao. Transmitir um modelo de Estado de Direito para uma sociedade sem registro historico anterior de sua implantacao implica mudar as atitudes das elites e das massas e criar uma cultura politica em que ninguem esta acima da lei. Infelizmente, defensores das reformas baseadas no rule of law tendem a ter em mente coisas mais simples e menos duradouras, como escrever Codigos e Estatutos e construir belos Tribunais.
Molecular Cloning of the cDNA Encoding pp36, a Tyrosine-phosphorylated Adaptor Protein Selectively Expressed by T Cells and Natural Killer Cells

Activation of T and natural killer (NK) cells leads to the tyrosine phosphorylation of pp36 and to its association with several signaling molecules, including phospholipase Cγ-1 and Grb2. Microsequencing of peptides derived from purified rat pp36 protein led to the cloning, in rat and man, of cDNA encoding a T- and NK cell–specific protein with several putative Src homology 2 domain–binding motifs. A rabbit antiserum directed against a peptide sequence from the cloned rat molecule recognized tyrosine phosphorylated pp36 from pervanadate-treated rat thymocytes. When expressed in 293T human fibroblast cells and tyrosine-phosphorylated, pp36 associated with phospholipase Cγ-1 and Grb2. Studies with GST–Grb2 fusion proteins demonstrated that the association was specific for the Src homology 2 domain of Grb-2. Molecular cloning of the gene encoding pp36 should facilitate studies examining the role of this adaptor protein in proximal signaling events during T and NK cell activation.
Identification of a malignant counterpart of the monocyte-dendritic cell progenitor in an acute myeloid leukemia

Myeloblasts derived from the peripheral blood of a patient with acute myelogenous leukemia (ORL47) were found to represent the malignant counterpart of the newly elucidated monocyte-dendritic cell colony- forming unit (mono-DC-CFU). The specific cytokine conditions require to achieve intermediate and terminal maturation of DCs and monocytes from these progenitors were defined. With tumor necrosis factor (TNF) + granulocyte-macrophage colony-stimulating factor (GM-CSF) + stem cell factor treatment numerous colony-like clusters developed. In contrast with normal DC development, further advancement of mono-DC-CFU and terminal DC maturation from the leukemic cells were dependent on the addition of interleukin-6. Functional and phenotypic analysis showed that the capacity to differentiate was maintained fully in the DC compartment, but only partially in the monocyte compartment, as judged by the lack of CD14 surface expression. Cells found at intermediate stages of DC development were potent stimulators of a mixed leukocyte reaction, a function usually attributed to mature DCs. As previously shown for normal DC development, antibodies to TNF alpha and GM-CSF blocked proliferative responses and DC growth. The importance of these observations in the classification of leukemias, normal DC development, and potential clinical strategies is discussed.
Psoas haematoma mimicking lumbar radiculopathy

A 72-year-old man presented to his primary care physician with 1 week of difficulty ambulating and right thigh pain and numbness. Physical exam revealed weakness in his right hip flexor and quadriceps, along with pain and numbness in an L3 distribution. The patient had …
CSF, blood-brain barrier, and brain drug delivery

ABSTRACTIntroduction: There are 2 misconceptions about the cerebrospinal fluid (CSF), the blood-brain barrier (BBB), and brain drug delivery, which date back to the discovery of a barrier between blood and brain over 100 years ago. Misconception 1 is that drug distribution into CSF is a measure of BBB transport. Misconception 2 is that drug injected into the CSF compartment distributes to the inner parenchyma of brain.Areas Covered: Drug distribution into the CSF is a function of drug transport across the choroid plexus, which forms the blood-CSF barrier, and not drug transport across the BBB, which is situated at the microvascular endothelium of brain. Drug injected into CSF undergoes rapid efflux to the blood compartment via bulk flow. Drug penetration into brain parenchyma from the CSF is limited by diffusion and drug concentrations in brain decrease exponentially relative to the CSF concentration.Expert Opinion: The barrier between blood and brain was discovered in 1913, when it was believed that the ...
Comparing Reproductive Inhibition in Female White-Footed Mice from Michigan and Virginia

This comparative study demonstrated that 70% of female Peromyscus leucopus novebora-censis from Michigan and 72% of those from Virginia, which were reared in the presence of a bisexual pair, were pregnant or had produced a litter by 150 days of age. The combined reproductive level of 71% for young females reared with bisexual pairs was not significantly different from that of young females reared in the presence of an adult male alone. In addition, no significant difference was observed across treatment groups with regard to age of vaginal introitus (39.0 ± 0.6 days) or age at first parity (91.5 ± 3.2 days). These results do not support a proposed high level of reproductive inhibition in young females induced by the adult females of bisexual pairs. Variations in previously reported data appear not to be due to any intrinsic differences between Michigan and Virginia animals.
Effect of Larval Diet on the Seasonal Occurrence of Diapause in the Pink Bollworm

The pink bollworm, Pectinophora gossypiella (Saunders), was reared in an open in sectary and in the laboratory on three synthetic diets. Diets utilized were a 5% cottonseed meal diet, a 1% cottonseed meal diet and a wheat germ diet. The 5% meal diet had the highest oil content and the wheat germ diet the lowest. Cultures were placed in the in sectary and laboratory locations at weekly intervals from late June to early November. Results indicated that diet had little effect on the occurrence of diapauses until other inductive stimuli came into play. The highest incidence of diapauses then on the diets having the greatest oil contents. When the period between sunrise and sunset decreased to approximately 12 hours (mid-September) or less, the incidence of diapauses increased abruptly in both the in sectary and the laboratory. Temperature appeared to have an additive effect to the photoperiodic stimulus; however, temperature alone may be sufficient stimulus to induce diapause in the pink bollworm.
Emissions of Fine Particle Fluoride from Biomass Burning

The burning of biomasses releases fluorine to the atmosphere, representing a major and previously uncharacterized flux of this atmospheric pollutant. Emissions of fine particle (PM2.5) water-soluble fluoride (F–) from biomass burning were evaluated during the fourth Fire Laboratory at Missoula Experiment (FLAME-IV) using scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDX) and ion chromatography with conductivity detection. F– was detected in 100% of the PM2.5 emissions from conifers (n = 11), 94% of emissions from agricultural residues (n = 16), and 36% of the grasses and other perennial plants (n = 14). When F– was quantified, it accounted for an average (±standard error) of 0.13 ± 0.02% of PM2.5. F– was not detected in remaining samples (n = 15) collected from peat burning, shredded tire combustion, and cook-stove emissions. Emission factors (EF) of F– emitted per kilogram of biomass burned correlated with emissions of PM2.5 and combustion efficiency, and also varied with the typ...
Abstract ED07-04: Identifying environment‐gene interactions that link social stress to altered cancer biology

Identifying the potential mechanisms linking psychosocial factors (e.g. chronic “stress”) to human disease susceptibility has been the subject of intense interest by both social and biological scientists for many years. Together, the endocrine and the autonomic nervous systems modulate an individual9s physiological response to social stress; both systems can mediate signaling pathways and gene expression changes at the subcellular level that have the potential to alter tumor biology. However, it is only recently that the detailed molecular components connecting biobehavioral factors and cancer biology have begun to be uncovered. For example, in preclinical models of both breast and ovarian cancer, there is growing evidence linking environmental stressors and ensuing changes in neuroendocrine dynamics to the promotion of tumor growth. These mechanisms include decreasing tumor cell apoptosis and increasing cell proliferation, tumor invasion, and angiogenesis. Assessing the mechanisms of gene by social environment interaction requires an appreciation of the subtleties of measuring the social environment, the individual9s behavioral and neuroendocrine response, as well as the tumor and its microenvironment. While cancer biologists are accustomed to examining the effects of a single physical variable on a well‐defined and measurable outcome, examining the physiological outcomes of an adverse social environment on tumor biology requires expanding expertise beyond the usual expertise of a tumor biologist. These studies require developing models that require scientists from diverse backgrounds of expertise to look beyond single agents and to consider the complexity of the individual9s interaction with the social environment, and the resultant molecular sequelae as it influences tumor development. Our laboratories9 recent collaborative development of a model of social isolation as it pertains to a transgenic model of human breast cancer (SV40Tag) and a Sprague‐Dawley female rat model of spontaneous mammary gland cancer will be presented. In both models, we found that chronic social isolation results in altered exploratory behavior to an open field as well as a heightened corticosterone response to a superimposed acute restraint stressor. In the SV40 Tag model, we were able to examine gene expression differences in the mammary glands of isolated versus grouped female mice prior to invasive tumor development and uncovered a significant increase in the expression of genes encoding lipid synthesis and glycolytic pathway enzymes, suggesting an association of the environment with cancer‐associated metabolic changes. The implications and limitations of these two breast cancer models ‐ one transgenic and one spontaneous ‐ will be discussed within the context of understanding mechanisms that confer biological risk in association with an unfavorable social environment. Citation Information: Cancer Prev Res 2010;3(1 Suppl):ED07-04.
THE GENERIC BASES OF STARE DECISIS: LEGAL POSITIVISM AS A RHETORICAL GENRE

(1985). THE GENERIC BASES OF STARE DECISIS: LEGAL POSITIVISM AS A RHETORICAL GENRE. Free Speech Yearbook: Vol. 24, No. 1, pp. 51-58.
Clinical use of B- and T-cell gene rearrangement analysis in hematopoietic disorders.

The clinical application of B- and T-cell gene rearrangement analysis is discussed relative to diagnostic problems in specific lymphoprolifer ative disorders. This article reviews the use of the Southern blot hybridization technique for B- and T-cell gene rearrangement detection in the analysis of various hematopoietic lesions. Several case studies are presented and analyzed.
Angiotensin II type 2 receptor stimulation of neuronal K+ currents involves an inhibitory GTP binding protein.

Angiotensin II (ANG II) elicits an ANG II type 2 (AT2) receptor-mediated increase in outward K+ current (IK; delayed rectifier K+ current) in neurons cocultured from rat hypothalamus and brain stem...