cssi/SciSciGPT-SciSciNet huggingface dataset:
Reversal agent inhibition of the multidrug resistance pump in human leukemic lymphoblasts.

Abstract Multidrug resistant cancer cells of the MDR-1 phenotype utilize an ATP-dependent pump to excrete toxic drugs. Rhodamine 123 (R123) is a fluorescent substrate of the MDR pump. An assay for the ATP-dependent initial efflux of R123 from CEM/VLB 100 human leukemic lymphoblasts has been developed. The MDR-1 cells were treated with a reversal agent and preloaded with 40.0 nM R123 in buffer at 30°C that contained sodium azide and 2-deoxyglucose. The cells were rinsed with cold buffer and resuspended in L -glutamine/ glucose solution at 23°C. The cell suspension was passed through a filter and R123 in the filtrate was detected at 2-s intervals by fluorescence. Efflux of R123 was inhibited by the reversal agents amiodarone, cyclosporin A, Ro11-2933 (DMDP), quinidine, and the optical isomers of propranolol. The MDR pump is stereospecific for the ( R )-diastereomer quinidine; however, the ( S )-diastereomer quinine is a relatively weak inhibitor of the pump. Cyclosporin A was the most potent inhibitor tested against the efflux of R123 by the MDR pump.
Interferon inhibitory activity in patients with multiple sclerosis.

Background Interferon inhibitory activity (IIA) is a logical candidate for explaining neutralizing antibody–negative partial responsiveness to interferon beta in multiple sclerosis (MS), but its role has not been evaluated. Objective To investigate the role of IIA and soluble interferon-α/β receptor (sIFNR) in determining response of patients with MS to interferon beta therapy. Design Parallel-group, open-label study. Setting Baird Multiple Sclerosis Center, Buffalo, NY. Patients Blood was obtained before and 24 hours after injection of interferon beta-1a from 38 anti–interferon beta neutralizing antibody–negative patients with relapsing-remitting MS and 16 untreated healthy controls. On the basis of clinical parameters of response to interferon beta therapy, the patients were divided into stable or good-responder (n = 20) and active or partial-responder (n = 18) groups. Main Outcome Measures Quantitative analyses of magnetic resonance imaging were obtained; the IIA and sIFNR levels were measured using bioassay and enzyme-linked immunosorbent assay, respectively. Results The IIA and sIFNR levels were elevated in MS patients compared with controls ( P P Conclusion The levels of IIA are associated with increased MS disease activity and with responsiveness to interferon beta therapy in anti–interferon beta neutralizing antibody–negative MS patients.
Stochastic Guard-Band-Aware Channel Assignment With Bonding and Aggregation for DSA Networks

Fading and shadowing along with the primary user dynamics make channel quality in dynamic spectrum access networks uncertain. Furthermore, the imperfect design of filters and amplifiers in wireless devices motivates the need for guard-bands (GBs) to prevent adjacent-channel interference. In this paper, we develop novel stochastic GB-aware sequential and batch channel assignment schemes that aim at maximizing the spectrum efficiency. In line with recent IEEE 802.11 and LTE standards, our schemes support bonding and aggregation. We propose two assignment models for each of the sequential and batch schemes: a static single-stage and an adaptive two-stage . In the static model, channel assignment is performed once such that the rate demands are probabilistically met. The adaptive model is a two-stage model, where the initial assignment may be corrected once uncertainties are partially revealed. We refer to our formulations of the sequential and batch static assignments as c hance-constrained stochastic s ubset- s um p roblem (CSSP) and c hance-constrained stochastic m ultiple s ubset- s um p roblem (CMSSP) , respectively. Moreover, we develop stochastic formulations for the sequential and batch adaptive assignments, which we refer to as two-stage CSSP with r ecourse (CSSPR) and two-stage CMSSP with r ecourse (CMSSPR) , respectively. Finally, we present computationally efficient simplified versions of CSSP and CSSPR with near-optimal performance.
Internal Friction in Ion-Implanted Silicon

Using a double-paddle oscillator, we have studied the internal friction of thin Si layers which have been disordered by ion implantation. We have identified the temperature-independent internal friction common to all amorphous solids below 10K, and also a narrow relaxation peak at ≈ 48K. This peak has been shown to be caused by divacancies in the damaged crystalline region underneath the amorphous layer. Thermal, rapid thermal, and laser-flash annealing have been compared. The minimum disorder is left after rapid thermal annealing.
Long-Term Follow-Up of Patients With Hypereosinophilic Syndrome Treated With Alemtuzumab, an Anti-CD52 Antibody

Abstract Background Relapsing, refractory patients with idiopathic hypereosinophilic syndrome (I-HES) and chronic eosinophilic leukemia–not otherwise specified (CEL-NOS) do not have many effective, durable therapeutic options. Alemtuzumab, an anti-CD52 antibody, has been reported to be an effective therapy due to inherent expression of CD52 on eosinophils. Methods A retrospective chart review of 12 patients treated with alemtuzumab at our center until 2012. Results Ten (83%) of 12 patients achieved complete hematologic response (CHR) after a median of 1 week for a median duration of 66 weeks, with the elimination of disease-related symptoms; 2 patients achieved partial hematologic remission hematologic remission (PHR). Patients with CHR who received alemtuzumab maintenance (n = 5) had a significantly longer time to progression than those patients who were only observed (n = 5) ( P = .01). Eleven patients relapsed (only one while on maintenance), and 6 were rechallenged with alemtuzumab. Five (83%) achieved second CHR after a median of 3.5 weeks, for a median duration of 123 weeks. Again, those given maintenance (n = 3) had a longer time to progression than those who were only observed ( P = .04). Adverse effects were mostly related to infusion reactions and lymphopenia-related viral infections (despite antibiotic prophylaxis). One patient developed Epstein-Barr virus–related lymphoma. Conclusions Alemtuzumab is an effective treatment for patients with relapsed, refractory idiopathic hypereosinophilic syndrome and chronic eosinophilic leukemia–not otherwise specified, in terms of both CHR achievement (even after repeated rechallenges) and duration (particularly if provided as a maintenance therapy). Common adverse effects are related to infusion reactions and immunosuppression.
Predicting weight outcomes in preadolescence: the role of toddlers' self-regulation skills and the temperament dimension of pleasure.

To investigate the role of toddlers’ self-regulation skills and temperament in predicting weight outcomes in preadolescence. Participants for this study included 195 children (114 girls) obtained from three different cohorts participating in a larger ongoing longitudinal study. At 2 years of age, participants participated in several laboratory tasks designed to assess their self-regulation abilities, including emotion regulation, sustained attention and delay of gratification, whereas parents filled out a temperament questionnaire to assess toddlers’ pleasure expression. Height and weight measures were collected when children were 4, 5, 7 and 10 years of age. Children also filled out a body image and eating questionnaire at the 10-year visit. Self-regulation skills in toddlers were associated with body mass index (BMI) development and pediatric obesity as well as body image/eating concerns. The temperament dimension of pleasure was also associated with BMI development and pediatric obesity but not body image/eating concerns. Self-regulation difficulties across domains as well as temperament-based pleasure in toddlers represented significant individual risk factors for the development of pediatric obesity 8 years later. Early self-regulation difficulties also contributed to body image and eating concerns that typically accompanied overweight children. The mechanisms by which early self-regulation skills and temperament-based pleasure may contribute to the development of pediatric obesity and associated weight concerns are discussed.
Robust control for a noncollocated spring-mass system

Robust control laws are presented for an undamped pair of coupled masses with a noncollocated sensor and actuator. This simple problem captures many of the features of more complex aircraft and space structure vibration control problems. The control problem is formulated in the structured singular value framework, which addresses the stability robustness to parameter variations directly. Controllers are designed by D-K iteration (commonly called /* synthesis), and the resulting high-order controllers are reduced using Hankel model reduction. Design specifications such as settling time, actuator constraints, insensitivity to measurement noise, and parameter uncertainty are achieved by the resulting controllers.
Strength of the s-f exchange interaction in rare-earth intermetallics

Abstract Recently determined values of the temperature-independent isotropic Knight shift in the non-magnetic rare-earth dialuminides, YAl2, LaAl2, and LuAl2, indicate that previous estimates of the s-f exchange interaction parameter J sf in the RAl2 series (R = rare earth) should be increased approximately 2.5 times. The new J sf values are in good agreement with those obtained in similar fashion for the rare-earth phosphides and arsenides. These results re-affirm the usefulness of the uniform polarization model as a description of magnetic interactions in rare-earth intermetallics.
Porous mullite ceramics through diphasic gels of large boehmite and small silica particles

Mullite formation process has been studied in stoichiometric mullite (3Al2O3·2SiO2) diphasic gel containing large boehmite (∼1 μm) and small silica (∼10 nm) particles. It has been found that initial mullitization did not take place inside the silica phase (cristobalite), but took place in the defect θ-alumina phase. θ-alumina was stabilized by silica when the temperature was below 1350°C. At temperatures above 1350°C, mullite crystallized directly. It was suggested that silica diffused into the pores (<1.8 nm) of θ-alumina and prevented the collapse of θ-alumina pore structure. On the other hand, when silica was not present, the pore structure of θ-alumina collapsed and α-alumina crystallized at ∼1100°C. Porous mullite ceramics were obtained by using special diphasic gels containing large boehmite and small silica particles.
Energy Potential of Biomass from Conservation Grasslands in Minnesota, USA

Perennial biomass from grasslands managed for conservation of soil and biodiversity can be harvested for bioenergy. Until now, the quantity and quality of harvestable biomass from conservation grasslands in Minnesota, USA, was not known, and the factors that affect bioenergy potential from these systems have not been identified. We measured biomass yield, theoretical ethanol conversion efficiency, and plant tissue nitrogen (N) as metrics of bioenergy potential from mixed-species conservation grasslands harvested with commercial-scale equipment. With three years of data, we used mixed-effects models to determine factors that influence bioenergy potential. Sixty conservation grassland plots, each about 8 ha in size, were distributed among three locations in Minnesota. Harvest treatments were applied annually in autumn as a completely randomized block design. Biomass yield ranged from 0.5 to 5.7 Mg ha−1. May precipitation increased biomass yield while precipitation in all other growing season months showed no affect. Averaged across all locations and years, theoretical ethanol conversion efficiency was 450 l Mg−1 and the concentration of plant N was 7.1 g kg−1, both similar to dedicated herbaceous bioenergy crops such as switchgrass. Biomass yield did not decline in the second or third year of harvest. Across years, biomass yields fluctuated 23% around the average. Surprisingly, forb cover was a better predictor of biomass yield than warm-season grass with a positive correlation with biomass yield in the south and a negative correlation at other locations. Variation in land ethanol yield was almost exclusively due to variation in biomass yield rather than biomass quality; therefore, efforts to increase biomass yield might be more economical than altering biomass composition when managing conservation grasslands for ethanol production. Our measurements of bioenergy potential, and the factors that control it, can serve as parameters for assessing the economic viability of harvesting conservation grasslands for bioenergy.
Construction of chromosomal recA mutants of Pseudomonas putida PpG2

Abstract The recA gene of Pseudomonas putida PpG2 was cloned by complementation of the recA mutations of Escherichia coli strains DH5α and HB1 recA and a downstream partial open reading frame. Two mutants of P. putida PpG2, strains JS387 and JS388, were constructed by insertional inactivation of recA with a tetracycline-resistance gene in both orientations. Both mutants acquired sensitivity to methyl methanesulfonate (MMS) and both failed to undergo homologous recombination. While the recA mutation of P. putida JS388 was complemented in trans by recA of P. putida, the JS387 mutant was difficult to transform and transformants exhibited varying degrees of sensitivity to MMS. Therefore, P. putida JS388 can be used as a carrier of recombinant plasmids, but JS387 is not a suitable host for this purpose.
Dielectric spectroscopy of small molecule pharmaceuticals-effect of sample configuration

In dielectric spectroscopy, a technique traditionally used to characterize molecular mobility in polymers, the sample is usually analyzed as a thin film. In recent years, the technique has been extended to characterize both drug substances and drug products and has revealed a correlation between molecular mobility and stability. However, for pharmaceutical systems, analysis of powders is strongly preferred over films. Therefore, the dielectric behavior of several compounds of pharmaceutical interest—nifedipine, indomethacin, itraconazole, and griseofulvin—obtained using powder and film samples were compared. The magnitudes of the intrinsic dielectric properties were affected by the sample configuration with the powder samples consistently yielding lower values. The use of effective medium theories enabled us to account for the effect of air in the powder samples. The relaxation time, a property of immense importance to the pharmaceutical community, was not influenced by the sample configuration. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3190–3196, 2014
Stochastic Generation of Regular Distributions

A new class of models is proposed to describe the dynamic processes leading to the establishment of regular spatial patterns of structures in natural systems. Simple mathematical arguments are used to compute the saturating densities of the distributions, and these results are verified by computer simulation of model systems.
Operational, organizational, and human resource factors predictive of customer perceptions of service quality

Abstract The overall objective of this study was to examine the relationship between total quality management (TQM) factors and business unit performance as measured by customer perceptions of service quality. Data were collected from 26 business units of larger service organizations. Analyses confirmed our hypotheses that customer perceptions would be a function of a combination of operational, organizational, and human resource factors that have been associated with TQM.
Applications of an MPD propulsion system

Recent studies of the self-field magnetoplasmadynamic (MPD) thruster indicate that the attainable value of thrust efficiency can be over 50% with argon propellant at 5000 sec. Projections for hydrogen propellant show that the specific impulse may exceed 10,000 sec. Improving performance projections such as these create a need for systems and applications studies to be updated. This paper reviews the configurations for an MPD propulsion system and those missions on which such a system might find application. An MPD propulsion system could be used for: (1) attitude control and stationkeeping of large space structures, (2) interorbit transportation, and (3) interplanetary propulsion. A trajectory analysis of a Saturn Orbiter using a nuclear power supply and an MPD propulsion system is presented. A LEO to GEO MPD-OTV concept is presented that uses a remote source transmitting power to the OTV in the form of microwaves. Trajectory analysis of this latter concept indicates that a payload of 20,000 kg can be delivered to GEO in about 20 days if the MPD propulsion system receives 20 MW of input power.
Private Self-Consciousness and the Retest Reliability of Self-Reports

Abstract Two studies were conducted to determine if the test–retest reliability of various self-report measures would be moderated by individual differences in levels of private self-consciousness. Consistent with past research, findings indicated general support for the hypothesis that subjects high in private self-consciousness display self-reports of greater reliability across time than subjects low in private self-consciousness. In addition, Study 1 found that the time interval separating the two test sessions (3 and 9 weeks apart) did not affect the enhanced reliability of self-reports among high private self-conscious subjects. The results were interpreted in terms of the notion that high private self-conscious subjects have articulated self-schemata of greater temporal stability than low private self-conscious subjects. Suggestions regarding the future study of the moderating influence of private self-consciousness on the reliability of personality scales were offered.
The Calculation of Transmission Coefficients at Heterogeneous Semiconductor Interfaces: A Case Study Based on the n-InP | poly(pyrrole) Interface

The n-InP | poly(pyrrole) interface is used as a case study to discuss the calculation of the transmission coefficient, describing the probability of majority carrier transfer, at a non-ideal semiconductor interface exhibiting anomalous behavior assumed to be due to a spatial distribution of barrier heights. The most notable anomaly is a weaker dependence of current on voltage than predicted by thermionic emission (i.e. quality or ideality factor greater than unity). Central to this discussion is the calculation of the equilibrium exchange current density J o and barrier height Φ b in light of a heterogeneous and potentially voltage-dependent barrier distribution. Various approaches to the measurement of Φ b and J o valid for semiconductor interfaces characterized by a uniform, voltage- and temperature-independent barrier are discussed when applied to a heterogeneous interface. In particular, the use of a capacitance-voltage measured barrier is demonstrated to result in an overestimation of κ whereas the use of a Richardson plot barrier is demonstrated to result in an underestimation. Depending on method, errors in excess of five orders-of-magnitude are observed for the n-InP | poly(pyrrole) interface under conditions where it exhibits only mildly anomalous behavior (ideality factor ≍ 1.2). The greatest confidence in the transmission coefficients occurs when the ideality factor is unity and the capacitance-voltage barrier agrees with the Richardson Plot barrier.
Can Welfare Mothers Hack it in College? A Comparison of Achievement between Tanf Recipients and General Population Community College Students

The achievement of a group of undergraduate students enrolled in a pilot program for welfare recipients in the form of TANF (Temporary Aid to Needy Families) was compared with the achievement of general population students at an urban community college. Grades attained in a basic level, introductory Psychology course were used to measure academic achievement. Additionally, TANF students' rates of academic retention and election to the Dean's list were compared to rates among the general population community college students, over a period of four semesters. Students in the TANF program attained higher grades in the Psychology course, were elected to the Dean's list at higher rates, and retained their enrollments at equal rates to general population students. The findings suggest that, given proper support, TANF recipients can become successful college students. Implications for the current debate around welfare reform, specifically around the issue of allowing secondary education to substitute for TANF wo...
Changes in GIP gene expression following bariatric surgery

After bariatric surgery, there is a significant improvement in type 2 diabetes (T2D). T2D has been linked to incretins, including glucose-dependent insulinotropic polypeptide (GIP). Analysis of bariatric surgery patients may help to understand the link between GIP and T2D. Twenty-three morbidly obese patients underwent Roux-en-Y gastric bypass (RYGB) or gastric banding. Overall, there were 12 RYGB (5 T2D; 7 nondiabetic) patients and 11 gastric band (7 T2D; 4 nondiabetic) patients. Preoperative and postoperative blood samples were collected. Total RNA was extracted, cDNA synthesized, and real-time quantitative PCR were used to quantify gene expression. Student’s t test was used for statistical analysis. Postoperatively, T2D resolved or improved in 83.3 % (10/12) of the diabetic patients. Six (4 RYGB, 2 bands) patients discontinued hypoglycemic medications and four (3 RYGB, 1 band) patients discontinued the majority of their hypoglycemic agents. The remaining two diabetic patients (bands) showed no improvement. Postoperative GIP gene expression increased 4.36-fold (p = 0.02) in diabetic RYGB patients, whereas diabetic band patients increased 1.4-fold (p = 0.25). All diabetic patients with either resolution or improvement of T2D, had a 3.4-fold increase (p = 0.01) but nonresponders decreased 0.69-fold (p = 0.41). Nondiabetic RYGB patients increased 2.21-fold (p = 0.07) versus a 0.81-fold (p = 0.37) decrease of nondiabetic band patients. This is one of the initial studies that show a significant increase in GIP gene expression following a RYGB. This increase correlates with the clinical resolution of T2D. The anatomical changes after RYGB may account for these changes. Based on this data, GIP may be a key peptide in the “foregut hypothesis” for resolution of T2D.
Timescales of transient processes in capillary electrophoresis

Abstract We apply numerical simulation based on fundamental physical properties to the study of the development of electroosmotic flow and thermal gradient formation that occur immediately after a potential is applied to a capillary filled with electrolyte. Electroosmotic flow requires a few hundred microseconds to develop. We confirm others' findings that radial thermal gradients are generally too small to dominate zone dispersion for capillaries with lumen diameters smaller than about 100 μm. The radial thermal gradient within the capillary lumen requires a few milliseconds to develop, but the general, whole-capillary temperature rise requires ten to a thousand times longer. We combine on one scale the major time-dependent processes that occur when an axial potential gradient is applied, and we demonstrate the theoretical feasibility of using modulated driving potentials to suppress thermal zone broadening.
Arenediazonium Salts: New Probes of the Interfacial Compositions of Association Colloids. 4.1-3 Estimation of the Hydration Numbers of Aqueous Hexaethylene Glycol Monododecyl Ether, C12E6, Micelles by Chemical Trapping†

Chemical trapping of water and terminal OH groups in nonionic micelles of hexaoxyethylene monododecyl ether, C12E6, by an aryl cation formed by spontaneous decomposition of an aggregate-bound 4-hex...
Does compliance mismatch alone cause neointimal hyperplasia

To define the relationship between compliance mismatch and the development of neointimal hyperplasia, one 3 cm segment of common iliac artery was externally banded in seven dogs, thereby fixing the arterial diameter at end diastole. To quantify compliance, end-diastole diameter and its change with pulse pressure were measured by induction angiometry. This technique uses intravascular soft trifilar wire probes introduced through distally placed polytetrafluoroethylene sidearms. Compliance was checked in the banded and contralateral undissected unbanded control iliac arteries at 3 and 6 months, at which times the vessels were fixed by perfusion, excised, and examined histologically. Sustained (6-month) compliance mismatch was successfully induced within the banded segments (p less than 0.0001), and no compliance mismatch was seen in the control segments (p = 0.357). The intima of all banded vessels was virtually indistinguishable from that in controls grossly and histologically. Mild focal intimal thickening, less than 3 cell layers thick involving less than 5% of the vessel circumference, was typically seen in both banded and control vessels (range 6.57 +/- 6.80 micron to 38.86 +/- 57.16 micron). In marked contrast, at the sites of the polytetrafluoroethylene-to-femoral artery anastomosis, near-occlusive neointimal hyperplasia (1714 +/- 415.47 micron) was seen in all animals. Residual lumen area in the banded and control vessels was only minimally abnormal (range 98.65% +/- 2.18% to 99.96% +/- 0.08%). These data indicate that compliance mismatch alone is an insufficient stimulus for the development of neointimal hyperplasia in the canine model.
Effect of climatic variability on δ13C and tree-ring growth in piñon pine (Pinus edulis)

Understanding the response of long-lived species to natural climatic variability at multiple scales is a prerequisite for forecasting ecosystem responses to global climate change. This study investigated the response of pinon pine (Pinus edulis) to natural climatic variability using information on physiology and growth as recorded in leaves and tree rings. δ13C of annual leaf cohorts (δ13Cleaf) and tree rings (δ13Cring) were measured at an ecotonal/xeric site and a mid-range/mesic site. Ring width indices (RWI) were used to estimate annual growth of individual trees. Relationships between seasonal and annual climate parameters and δ13C and growth were investigated. δ13C–climate relationships were stronger for δ13Cleaf than for δ13Cring especially at the xeric site. The mean monthly maximum summer temperatures over May through September (summer T max) had the strongest influence on δ13Cleaf. There was a strong negative relationship between RWI with summer T max and a strong positive relationship between RWI with October to October precipitation (water–year PPN) at both sites. This suggests that pinon pine populations could be vulnerable to decreased growth and, perhaps mortality, in response to warmer, drier conditions predicted by models of global climate change.
The fatty acid composition of three unicellular algal species used as food sources for larvae of the American oyster (Crassostrea virginica)

The total lipid and fatty acid content of 3 algal species,Pyramimonas virginica, Pseudoisochrysis paradoxa andChlorella sp., which have been successful as food sources for rearing larvae of the American oyster,Crassostrea virginica, was determined. Of the fatty acids of ω6 and ω3 families which have been shown to be essential fatty acids for normal growth in many animals, only the ω6 fatty acids were found to be higher in these 3 species of algae than in the traditional oyster larvae diet which consists of the algaeMonochrysis lutheri andIsochrysis galbana. The major fatty acid constituents of the total lipids of the 3 species were the C12, C14, C16 and C18 saturated fatty acids and the C16 and C18 mono- and polyunsaturated acids. These components constituted 70–93% of the total lipid in cultures of all ages. There were modest amounts of C20 and C22 polyunsaturated acids; some of these existed only in trace amounts. InP. virginica andChlorella sp., hexadecanoic acid was dominant (23–39%). The presence of large quantities of tetradecanoic acid (22–26%) and oleic acid (17–21%) was characteristic ofP. paradoxa. Chlorella sp. had the highest proportion of octadecatrienoic acid (18∶3ω3) which accounted for up to 17% of the total lipids. γ-Linolenic acid (18∶3ω6) was found only inChlorella sp., but in the 5th-day culture only. The lowest proportion of total polyethylenic acid was inP. paradoxa; however, lipid analyses showed this alga had the most lipid/individual cell. Some variations were observed in the fatty acid composition with age of the culture.
Characterization and Phylogenetic Relationships of Photorhabdus luminescens subsp. sonorensis (γ-Proteobacteria: Enterobacteriaceae), the Bacterial Symbiont of the Entomopathogenic Nematode Heterorhabditis sonorensis (Nematoda: Heterorhabditidae)

Photorhabdus are motile Gram-negative bacteria that have a mutualistic association with Heterorhabditis nematodes (Heterorhabditidae). These bacteria possess peculiar biochemical characteristics such as inability to reduce nitrates, and the capacity to ferment only a limited number of carbohydrates. Heterorhabditis nematodes vector the bacteria from one insect host to another and also provide shelter to the bacteria from soil stressors and antagonists. Once inside the insect host, the bacterial symbionts are released and produce toxins and secondary metabolites and broad-spectrum antibiotics, which kill the host by septicemia within 48 h. At present, three Photorhabdus spp. have been identified: P. luminescens, P. temperata, and P. asymbiotica, and many subspecies have also been described. Characterization of new species and subspecies has been based on sequence data, mostly of the 16S rDNA, and also of a selection of protein coding genes. In addition to this, phenotypic traits including temperature growth, colony morphology, color, light production, carbohydrate response, and assimilation, among others, have been considered. In this study, we characterize the bacterial symbiont of Heterorbabditis sonorensis, a recently discovered entomopathogenic nematode species form the Sonoran desert in Arizona, USA. A selection of classic biochemical and molecular methods including sequence data of six genes: 16s rDNA, and four protein coding genes: gyrB, recA, gltX, and dnaN were considered. Evolutionary relationships of this new Photorhabdus subsp. were inferred considering maximum parsimony and Bayesian analyses.
Residents' evaluation of behavioural paediatrics instruction

Summary. This study sought to explore the following questions: (1) Do residents perceive training focused on infancy and early childhood care issues as more clinically applicable than training focused on care of older children and adolescents? (2) Do residents at different training levels differ in their evaluation of behavioural paediatrics instruction? (3) What is the strength of the association between instructional style and clinical impact dimensions? and (4) Compared to the instruction provided by instructors from other medical and academic disciplines, do paediatric residents perceive differences in the teaching efficacy and clinical relevance of instruction provided by paediatricians? Data were drawn from 1341 residents' evaluations of 116 required behavioural paediatrics sessions over 3 years. The data demonstrated that house officers recognize the value of acquiring knowledge in behavioural paediatrics, regardless of the level of the house officers' training, or whether the focus concerned infants or older children. However, residents were more likely to perceive the presentations provided by paediatricians as providing instruction that was slightly more applicable to their practice needs than instruction that other faculty presented. The study results further demonstrated that the clarity and organization of instruction influences, but does not supercede, the residents' perception of the merit of instruction. The findings suggest that international recommendations for greater inclusion and acceptance of behavioural paediatric instruction can be achieved in programmes that, by requiring participation, confer equal status to behavioural paediatrics and traditional residency training. The results support residents' acceptance of a health team approach to behavioural paediatric instruction. The involvement of paediatric teachers, who are able to identify explicitly the clinical relevance of the instructional material, further enhances residents' perceptions of the value of behavioural paediatric education.
A quantitative ultrastructural study of microtubules in transformed and nontransformed cells in vitro

Abstract The amount of polymerized tubulin in nontransformed (Swiss mouse 3T3 fibroblast) and transformed cells (SV-3T3 cells) has been quantitated by point counting methods. Division of the cell into centriolar and noncentriolar regions and perinuclear and peripheral microtubule volume densities (MVD) and comparison of these populations with a three-way analysis of variance indicated statistically significant interaction between cell type, centriolar/noncentriolar regions and perinuclear/peripheral MVDs. This interaction in conjunction with the mean MVDs suggests that cell transformation is associated with a decrease in the perinuclear and peripheral MVDs of non-centriolar regions. Because the perinuclear MVD of centriolar regions of 3T3 and SV-3T3 cells were not significantly different we conclude that organizing centers nucleate equivalent numbers of microtubules in both cell types. The decrease in MVD in noncentriolar regions of transformed cells may be due to shorter microtubules which extend from organizing centers but fail to reach the plasma membrane and/or do not loop back into the cytoplasm from the plasma membrane.
Robust adaptive control of time-varying linear plants using polynomial approximation

The robust adaptive control of time-varying linear systems in the presence of bounded external disturbances is discussed. A new polynomial approximation scheme is proposed to approximate unknown time-varying parameters of the plant. A modified least-squares estimator with a relative dead zone is applied to identify the resulting unknown parameters. The control law is derived by minimising a quadratic cost function which penalises both model tracking errors and excessive control actions. It is shown theoretically that robust stability can be established in the presence of unmodelled dynamics due to approximate errors and external disturbances. Simulation results demonstrate the effectiveness of the proposed new controller.
Optical rectenna solar cells using graphene geometric diodes

A solar cell using micro-antennas to convert radiation to alternating current and ultrahigh-speed diodes to rectify the AC can in principle provide extremely high conversion efficiencies. Currently investigated rectennas using metal/insulator/metal (MIM) diodes are limited in their RC response time and have poor impedance matching to the antenna. We have investigated a new rectifier, referred to as a geometric diode, which can overcome these limitations. The geometric diode consists of a conducting thin-film, such as graphene, patterned in a geometry that leads to diode behavior. We have experimentally demonstrated geometric diodes made from graphene and simulated their characteristics using the Drude model for charge transport. Here we compare the characteristics of rectennas using MIM diodes with those based on geometric diodes and show the improved performance of the latter.
Fuzzy sets and Boolean-valued universes

Abstract A connection between fuzzy sets and Boolean-valued universes is made by developing a formal axiomatic system for fuzzy sets among whose models are suitably interpreted Boolean-valued universes. The formal system is an independent first-order axiomatization of fuzzy set theory which parallels the Zermelo-Fraenkel development of classical set theory.
Increased Virulence and Competitive Advantage of a/α Over a/a or α/α Offspring Conserves the Mating System of Candida albicans

The majority of Candida albicans strains in nature are a/α and must undergo homozygosis to a/a or α/α to mate. Here we have used a mouse model for systemic infection to test the hypothesis that a/α strains predominate in nature because they have a competitive advantage over a/a and α/α offspring in colonizing hosts. Single-strain injection experiments revealed that a/α strains were far more virulent than either their a/a or α/α offspring. When equal numbers of parent a/α and offspring a/a or α/α cells were co-injected, a/α always exhibited a competitive advantage at the time of extreme host morbidity or death. When equal numbers of an engineered a/a/α2 strain and its isogenic a/a parent strain were co-injected, the a/a/α2 strain exhibited a competitive advantage at the time of host morbidity or death, suggesting that the genotype of the mating-type (MTL) locus, not associated genes on chromosome 5, provides a competitive advantage. We therefore propose that heterozygosity at the MTL locus not only represses white-opaque switching and genes involved in the mating process, but also affects virulence, providing a competitive advantage to the a/α genotype that conserves the mating system of C. albicans in nature.
Vapor phase polymerization of 1,3‐butadiene with sodium

Apparatus and technique have been described for the polymerization of 1,3-butadiene in the vapor phase with sodium as catalyst. Research grade butadiene or that obtained from alcohol is necessary for production of high molecular weight polymers by this method. Unmodified polymerizations with increased sodium surface go faster and produce polymers of lower gel content and inherent viscosity. Increase in polymerization temperature reduces the rate, gel content, and inherent viscosity. The chemical structure of the modifier seems to be the predominant factor in its efficiency within a concentration range of 0.1 to 1.0 %. Ethyl chloride is the most powerful modifier of those examined, followed in order by dimethylamine, acetaldehyde, and acetoue. Gelfree polymers with average inherent viscosities of the whole sol between 0.4 and 4.6 were vulcanized and evaluated. The weight distribution was found to be rather narrow for the low viscosity polymers but to become broader as the average inherent viscosity of the polymer increased. Optimum processing and tensile properties were obtained on the polymers of medium viscosity. The dynamic properties of the vulcanizates improve with increase in average inherent viscosity of the raw polymer; the ethyl chloride modified polymer is exceptionally good. The physical properties of the vulcanizate of a blend of equal parts of five polymers of inherent viscosity 1.0 to 4.6 were near those of the lowest molecular weight polymer.
Expectancies and memory for spatiotemporal events in 5-month-old infants☆

Five-month-old infants were trained to fixate four event locations, and recall was assessed following training in three experiments. Memory for four events was demonstrated in the first two studies, and memory for these events was also found to be robust following a 6- to 7-day delay. Infants demonstrated that they can anticipate upcoming events during training: they increased anticipatory behaviors during latter training trials, and they appeared to form expectancies of future events during periods of both stimulus onset and stimulus offset. Results are interpreted as consistent with a script representational view of memory for spatiotemporal events.
Chloroquine terminates stretch-induced atrial fibrillation more effectively than flecainide in the sheep heart.

Background— Blockade of inward-rectifier K+ channels by chloroquine terminates reentry in cholinergic atrial fibrillation (AF). However, it is unknown whether inward-rectifier K+ channels and reentry are also important in maintaining stretch-induced AF (SAF). We surmised that reentry underlies SAF, and that abolishing reentry with chloroquine terminates SAF more effectively than traditional Na+-channel blockade by flecainide. Methods and Results— Thirty Langendorff-perfused sheep hearts were exposed to acute and continuous atrial stretch, and mapped optically and electrically. AF dynamics were studied under control and during perfusion of either chloroquine (4 µmol/L, n=7) or flecainide (2–4 µmol/L, n=5). Chloroquine increased rotor core size and decreased reentry frequency from 10.6 ± 0.7 Hz in control to 6.3 ± 0.7 Hz ( P 8 Hz. During pacing (n=11), flecainide reversibly reduced conduction velocity (≈30% at cycle length 300, 250, and 200 ms; P <0.05) to a larger extent than chloroquine (11% to 19%; cycle length, 300, 250, and 200 ms; P <0.05). Significant action potential duration prolongation was demonstrable only for chloroquine at cycle length 300 (12%) and cycle length 250 ms (9%) ( P <0.05). Conclusions— Chloroquine is more effective than flecainide in terminating SAF in isolated sheep hearts by significantly increasing core size and decreasing reentry frequency. Chloroquine’s effectiveness may be explained by its inward-rectifier K+ channel blockade profile and suggest that reentry is important to maintain acute SAF.
Accessing User Facilities and Making your Research Experience Successful

Access to many of the world's leading user facilities is easier than ever before, with web-based tutorials providing everything from instrumental overviews and example applications to online safety training. Submission of proposals for experiment time at large, heavily subscribed facilities, including synchrotron and neutron sources, has been streamlined with web-based submission. Support, which is commonly the key to successful experiments, is provided by facility staff and experienced users, allowing new users to begin experiments with minimal experience. Increasingly Earth scientists are taking advantage of the wide range of unique instrumentation at user facilities. Here, we explain how you can, too.
Development of Cellular Immunity in Cutaneous Leishmaniasis Due to Leishmania tropica

A laboratory worker was inadvertently inoculated with infectious material while passaging amastigotes of Leishmania tropica. The subsequent development of a cutaneous lesion was correlated with results of sequential in vitro bioassays of cell-mediated immunity. Induction of lymphocyte proliferation and interleukin 2 production by soluble L. tropica antigens appeared within five weeks of infection and reached maximal levels coincident with ulceration of the skin lesion. Thereafter interleukin 2 production rapidly decreased, whereas the lymphocyte proliferative response declined more slowly. Biopsy of the lesion after 12 weeks, at a time when antigen-induced lymphocyte proliferation was still significantly elevated but interleukin 2 activity had returned to near baseline values, demonstrated no organisms either histologically or by culture. Healing was complete after 20 weeks. These studies provide data on the kinetics of the development of cell-mediated immunity in human cutaneous leishmaniasis and suggest the usefulness of in vitro bioassays of specific immune reactivity to parasites for evaluating effective cell-mediated immunity.
A family of putative MSCRAMMs from Enterococcus faecalis.

The recently published Enterococcus faecalis genome [ Paulsen, I. T., Banerjei, L., Myers, G. S. & 29 other authors (2003). Science 299, 2071–2074) ] was examined and 41 putative cell-wall-anchored proteins were identified. Seventeen of these proteins are predicted to contain tandemly repeated immunoglobulin-like folds characteristic of the structural organization of staphylococcal adhesins of the MSCRAMM (microbial surface component recognizing adhesive matrix molecules) type. Two of the nine proteins selected for further study appear to represent cell-wall-anchored enzymes. It is proposed that the remaining seven proteins constitute a family of structurally related proteins potentially interacting with proteins of the host. This family includes the previously identified collagen/laminin-binding MSCRAMM ACE [ Rich, R. L., Kreikemeyer, B., Owens, R. T., LaBrenz, S., Narayana, S. V., Weinstock, G. M., Murray, B. E. & Hook, M. (1999). J Biol Chem 274, 26939–26945 ]. It is further demonstrated that genes encoding the seven putative MSCRAMMs are present in all E. faecalis strains tested and these proteins appear to be expressed during infection in humans, since sera from infected individuals contain antibodies reacting with recombinant versions of the enterococcal proteins.
A lower bound on the error probability for signals in white Gaussian noise

The performance of specific signal constellations in digital communications problems is often described through use of the union bound, an upper bound which is asymptotically tight with respect to the signal-to-noise ratio. It is not unnatural to ask how tight this result is for small to medium values of signal-to-noise ratio; one way to answer this question is to develop an asymptotically tight lower bound. Such is the goal of the present paper. >
Chronic heart failure: a look through the rear view mirror.

This editorial refers to ‘Predicting survival in heart failure: a risk score based on 39 372 patients from 30 studies’, by S.J. Pocock et al., doi:10.1093/eurheartj/ehs337 Heart failure is now the most common condition that leads to hospital admission in industrialized nations. Although the overall prognosis for patients with chronic heart failure is still gloomy, and similar to that of many of the most common forms of cancer,1 a combination of pre-clinical and clinical research conducted over the past 25 years has led to five significant advances, each of which has received a IA recommendation in the European Society of Cardiology Guidelines for the treatment of heart failure with reduced ejection fraction.2 These advances, well known to cardiologists, are: (i) blockers of the renin–angiotensin system [angiotensin-converting enzyme (ACE) inhibitors or angiotensin II type I receptor blockers (ARBs)]; (ii) beta-adrenergic blockers; (iii) aldosterone antagonists; (iv) implantation of cardioverter-defibrillators; and (v) the application of cardiac resynchronization therapy in patients with QRS prolongation. Each has been shown to reduce mortality in patients with heart failure. As a consequence, the cumulative benefits of these therapies has improved the prognosis in these patients quite substantially.3 The development of a management plan for individual patients with heart failure (as is the case with many conditions) requires an assessment of prognosis. This has been a challenging task in patients with chronic heart failure. A number of risk scores have been established since 2003 to …
Indications for Surgical Management of Hyphema in Patients With Sickle Cell Trait

• We analyzed 22 sickle cell trait hyphemas. Fourteen of the 22 eyes were adequately controlled with medical therapy alone, ie, the intraocular pressure averaged less than 25 mm Hg during consecutive 24-hour periods and there were no repeated transient rises of IOP above 30 mm Hg. Surgery was performed in eight eyes, because of inadequate medical control. Thirteen of the 14 medically treated eyes had acceptable levels of IOP within the first 24 hours; only one of the eight surgically treated eyes had adequate control during the first 24 hours. This suggests that control during the first 24 hours portends a good prognosis, while lack of control during that period predicts continued difficulty managing the IOP. This seems to be important in view of previous experience that suggests that these eyes do not tolerate minimal to moderate elevations in IOP as well as those of patients without sickle cell anemia.