cssi/SciSciGPT-SciSciNet huggingface dataset:
Conjugated Polymers in Layered Hosts: Formation of Emeraldine Salt and Polyfuran in FeOCl

Electrically conducting polymers have received a great deal of attention due to their promising electrical properties and potential applications1, 2. Our understanding of the structure of these systems is still fragmentary due to their quasi-crystalline nature and insolubility in common organic solvents. Important structural problems associated with single chain and their macromolecular aggregation remain to be solved. The systematic control and modification of their physical, structural and electronic properties is an active area of research. Goals include the optimization of the charge transport properties and the better understanding of the relationship between electronic and lattice structure.
Adolescents as the Family Technology Innovators

Socialization theory and a child effects perspective, along with diffusion of innovation, suggest that not only are adolescents emerging as active users of technology, they are also change agents, introducing innovations and technologies into the family and teaching parents to use new technologies. In the current chapter, I consider the role of technologies in families with adolescents: the ways that family relationships impact technology use, and the ways in which technology use impacts family relationships. Next, a case will be made to recognize a flip in the family’s power dynamic, as youth are now the drivers and innovators. Last, future directions for research and implications for practice will be considered.
Real-time capable modeling of neutral beam injection on NSTX-U using neural networks

A new model of heating, current drive, torque and other effects of neutral beam injection on NSTX-U that uses neural networks has been developed. The model has been trained and tested on the results of the Monte Carlo code NUBEAM for the database of experimental discharges taken during the first operational campaign of NSTX-U. By projecting flux surface quantities onto empirically derived basis functions, the model is able to efficiently and accurately reproduce the behavior of both scalars, like the total neutron rate and shine through, and profiles, like beam current drive and heating. The model has been tested on the NSTX-U real-time computer, demonstrating a rapid execution time orders of magnitude faster than the Monte Carlo code that is well suited for the iterative calculations needed to interpret experimental results, optimization during scenario development activities, and real-time plasma control applications. Simulation results of a proposed design for a nonlinear observer that embeds the neural network calculations to estimate the poloidal flux profile evolution, as well as and fast ion diffusivity, are presented.
The expansion of the public sector in federalism: a comparative analysis of a macro level governing structure and government size

Utilising Oates’ fiscal federalism theorem, the Tiebout model and Berry’s common pool model, this paper examines the effects of four characteristics of a macro level governing structure on public s...
Simulation of manufacturing induced fiber clustering and matrix voids and their effect on transverse crack formation in unidirectional composites

Abstract This work is a contribution to the fields of computational micromechanics and virtual testing of fiber reinforced composite materials. Particular focus is on deriving trends related to the early failure events leading to crack formation in unidirectional composites under transverse tension. A simulation scheme is proposed to capture fiber clustering and matrix microvoids in a resin infusion process. A systematic procedure is developed to quantify these manufacturing induced defects in terms of fiber displacements (mobility) from an initially dry fiber bundle to the fully resin-infused composite. Using established methods for stochastic characterization of microstructures, the minimum size of a representative volume element (RVE) is estimated and its multiple realizations are used in an embedded cell model for finite element based computation of the local stress fields. Strain energy based point-failure criteria are then employed to ascertain occurrence of the most likely first failure mechanism. A matrix crack is assumed to form by coalescence of the point-failures as precursors. Parametric studies are performed to clarify the effects of the degree of fiber clustering, the volume fraction of matrix microvoids and the constituent properties on transverse crack formation. Experimental data available in the literature support the predictions of the simulations.
Electrothermal performance limit of β-Ga2O3 field-effect transistors

A β-Ga2O3 field effect transistor (FET) outperforms a GaN FET in Baliga's figure of merit (FOM) by 400% and Huang's chip area manufacturing figure of merit by 330%, suggesting that β-Ga2O3 could be a substrate of choice for next generation power transistors. However, its low thermal conductivity leads to extreme self-heating, which deteriorates the device performance during high voltage operation. A holistic evaluation of performance from a material-device-circuit perspective is necessary before reaching any conclusion regarding the technological viability of β-Ga2O3. In this paper, we develop a multiphysics and multiscale model for a material-device-circuit analysis of β-Ga2O3 FETs. The framework allows us to explore the effectiveness of various device design strategies (e.g., thermal shunts) for mitigating the thermal chokepoints and compare the performance of improved β-Ga2O3 FETs against that of GaN and SiC FETs. We highlight the limitations of traditional FOMs to analyze the relative performance of the new generation of power transistors whose structure incorporates stacked layers of materials with different thermal conductivities, like those of β-Ga2O3 FETs. We suggest device design strategies, such as wafer thinning, incorporation of heat shunts, and improved channel mobility, so that β-Ga2O3 FETs can compete commercially with GaN and SiC technologies.
Stratified performance on the Test of Memory Malingering (TOMM) is associated with differential responding on the Personality Assessment Inventory (PAI)

Introduction: This study evaluated symptom endorsement patterns in participants at various stratified performance levels on the Test of Memory Malingering (TOMM). It was hypothesized that the lowes...
Personal Freedom: The Action Model

This chapter addresses the action model of freedom in order to expose its weaknesses. The specific target of discussion is Isaiah Berlin’s notion of negative freedom. Some versions of the action model do not think this notion goes far enough to explain personal freedom, but all seem agreed that it introduces a necessary feature of this freedom. Since on the view defended here this conclusion is considered misguided, establishing grounds for the rejection of negative freedom should undermine the action model. Two versions of negative freedom, prominent in the literature (freedom as the opportunity to act and freedom as the opportunity to satisfy desires), are discussed, and objections raised against both.
The Einstein-Infeld-Hoffmann legacy in mathematical relativity I: The classical motion of charged point particles

Einstein, Infeld and Hoffmann (EIH) claimed that the field equations of general relativity theory alone imply the equations of motion of neutral matter particles, viewed as point singularities in s...
Corrosive Behavior of 3D–Printed 316L Stainless Steel

Additively manufactured metals such as stainless steels have promising futures because of their adaptive and one-step fabrication. However, an understanding of their properties and behavior in corrosive environments has not yet been achieved. This is due to a lack of methodology used to study the morphology of interior surfaces in porous materials. Thus, this research investigates the corrosion characteristics of three-dimensional–printed stainless steels made with five volume printing powers. Accelerated corrosion experiments were conducted at 35°C–40°C under atmospheric pressure in salt fog under predesigned durations. Electrochemical study was carried out with a potentiostat. Tomographic studies were conducted using a scanning electron microscope and micro X-ray computed tomography technology to analyze the effects of corrosion. Results revealed three findings. First, corrosion took place internally for all additively manufactured stainless steel samples regardless of printing parameters. Second, localized corrosion between printed layers was most pronounced. Third, elongated and oriented internal pits formed during corrosion and were associated with a dendrite-like structure, which is different from the conventional understanding of subsurface pitting directed by gravity. This research not only generates new knowledge on additively manufactured stainless steels but also opens new revenues for future investigation on the design and additive manufacturing of metals and alloys.
Ex vivo human testes as a practical model to simulate ultrasound-guided testicular cell transplantation for human fertility restoration

Objective To develop an ex vivo model to practice ultrasound-guided injection of cellular material into human seminiferous tubules to simulate testicular cell transplantation (TCT). Design Simulated TCT injections were performed in human testes removed during orchiectomy. The rete testis was the target site of injection. Successful retrograde infiltration of injected material into the lumen of the seminiferous tubules was detected using ultrasound and confirmed with histology. Setting Single academic surgical center. Patient(s) Adult patients undergoing orchiectomy for nononcologic indications. Intervention(s) The testes were injected with sonographic contrast (Optison), methylene blue, and fluorescent-labeled cells. Main Outcome Measure(s) A characteristic streaming pattern of sonographic contrast in the testis was used to define sonographic success, and the presence of methylene blue and fluorescent-labeled cells within the seminiferous tubules confirmed histologic success. Result(s) We performed simulated TCT injections in 30 testes obtained from 16 patients undergoing orchiectomy. We were able to achieve sonographic success in 57% of injections and confirmed that sonographic success is correlated with histologic success. Conclusion(s) Testicular cell transplantation injections can be practiced using human testes. As there appears to be a learning curve associated with this procedure, developing this infrastructure to practice these skills is critical before implementation in patients.
Depth Videos for the Classification of Micro-Expressions

Facial micro-expressions are spontaneous, subtle, involuntary muscle movements occurring briefly on the face. The spotting and recognition of these expressions are difficult due to the subtle behavior, and the time duration of these expressions is about half a second, which makes it difficult for humans to identify them. These micro-expressions have many applications in our daily life, such as in the field of online learning, game playing, lie detection, and therapy sessions. Traditionally, researchers use RGB images/videos to spot and classify these micro-expressions, which pose challenging problems, such as illumination, privacy concerns and pose variation. The use of depth videos solves these issues to some extent, as the depth videos are not susceptible to the variation in illumination. This paper describes the collection of a first RGB-D dataset for the classification of facial micro-expressions into 6 universal expressions: Anger, Happy, Sad, Fear, Disgust, and Surprise. This paper shows the comparison between the RGB and Depth videos for the classification of facial micro-expressions. Further, a comparison of results shows that depth videos alone can be used to classify facial micro-expressions correctly in a decision tree structure by using the traditional and deep learning approaches with good classification accuracy. The dataset will be released to the public in the near future.
Dominance of Wildfires Impact on Air Quality Exceedances during the 2020 Record-Breaking Wildfire Season in the United States

The western United States experienced a record-breaking wildfire season in 2020. This study quantifies the contribution of wildfire emissions to the exceedances of health-based National Ambient Air...
Wanted: The Intersection of Feminist Pedagogy and Science Education

As a graduate student earning a doctorate in science education and a certificate in women’s studies, I often found myself torn between two worthwhile fields that used two very distinct approaches to pedagogy and content. My experiences granted me an opportunity to explore the differences between these two fields and how the incorporation of feminist pedagogy could positively shape future science education courses. Exploring this topic through literature and my own experiences, I first focus on the differences between classic (science education) and feminist epistemology, and the importance of framing science education within feminist epistemology. I then discuss how we can model and enact feminist pedagogy in science education. I conclude with my thoughts on the potential intersection of feminist pedagogy with science education. “...girls should not be taught physical science except at the most elementary level, because the expenditure of nervous energy involved in the mastery of analytic concepts would be injurious to their health” – W. Felter, 1906. (Kelly, 1981, p. 1)
What Gives? A Study of Firms' Reactions to Cash Shortfalls

This paper examines the relative magnitude of financial versus real frictions by looking at how firms react to cash shortfalls. We use a regression discontinuity design in which the discontinuity is the point of violation of underfunding of corporate defined benefit pension plans. We reexamine the puzzling evidence in Rauh (2006) that mandatory pension contributions cause investment declines, finding that these results are likely due to the endogeneity that this study is trying to avoid. We also compare firm-year observations in which the firm's pension assets are just barely less than its pension liabilities to observations in which assets are just greater than liabilities. In this quasi-experimental setting, we find little evidence that firms cut back on investment. Instead, they mostly use a variety of financial tools, such as receivables factoring and payout cuts, to fund their pension liabilities.
Anthropology in the German Democratic Republic: A Personal Odessey

Anthropology as an academic discipline varies considerably cross-nationally. My Fulbright Lectureship in the Department of British and American Studies at Humboldt University in East Berlin during September 1988 February 1989 provided me with the opportunity to meet fellow anthropologists who acquainted me with the history and organization of our discipline in the German Democratic Republic. Dr. Walter Rusch in Bereich Ethnographie at Humboldt University and Professor Karl Sommer, Director of the institute for Anthropology at Humboldt University, played particularly significant roles in my personal odyssey through GDR anthropology. My contacts with GDR anthropologists also brought me into contact with anthropologists from other European countries, including Emmanuel Terray from the Ehess African Studies Center in Paris, Tamas Hoffman (the General Director of the Ethnographic Museum in Budapest), Josef Kotecs (the University of Debrecen in Hungary), Professor Piminov (Director of the Ethnographic Institute at Moscow University), and Josef Wolf (Member of the Czechoslovak Academy of Sciences in Prague).
Dopamine transport function is elevated in cocaine users.

Dopaminergic transmission has been suggested to be a primary mechanism mediating reinforcement, withdrawal and craving associated with psychostimulant addiction. Pyschostimulants attenuate dopamine transporter (DAT) clearance efficiency, resulting in a net increase in synaptic dopamine levels. Re-uptake rate is determined by the number of functional DAT molecules at the membrane surface. Previous in vivo imaging studies in humans and in vitro studies in post-mortem human brain have demonstrated that chronic cocaine abuse results in a neuroadaptive increase in DAT-binding site density in the limbic striatum. Whether this increase in DAT availability represents an increase in the functional activity of the transporter is unknown. Here, we present evidence that DAT function is elevated by chronic cocaine abuse. The effect of increasing post-mortem interval on the functional viability of synaptosomes was modeled in the baboon brain. Baboon brains sampled under conditions similar to human brain autopsies yielded synaptosomal preparations that were viable up to 24 h post-mortem. Dopamine (DA) uptake was elevated twofold in the ventral striatum from cocaine users as compared to age-matched drug-free control subjects. The levels of [3H]DA uptake were not elevated in victims of excited cocaine delirium, who experienced paranoia and marked agitation prior to death. In keeping with the increase in DAT function, [3H]WIN 35,428 binding was increased in the cocaine users, but not in the victims of excited delirium. These results demonstrate that DA uptake function assayed in cryopreserved human brain synaptosomes is a suitable approach for testing hypotheses of the mechanisms underlying human brain disorders and for studying the actions of addictive drugs in man.
Boundaries of dreams, boundaries of dreamers: thin and thick boundaries as a new personality measure.

Previous work by the author and his collaborators on frequent nightmare sufferers demonstrated that these people had striking personality characteristics which could be called "thin boundaries" in a number of different senses. In order to measure thin and thick boundaries, a 145-item questionnaire, the Boundary Questionnaire, has been developed which has now been taken by over 1,000 persons. Preliminary results are presented indicating that, as predicted a priori, several new groups of nightmare sufferers and groups of art students scored usually "thin," whereas a group of naval officers had usually "thick" boundaries. Overall, thinness on the Boundary Questionnaire correlated highly positively (r = .40) with frequency of dream recall and also significantly (r = .16) with length of sleep.
A Phenomenological Case Study: Successful Management of a Child Who Stutters

This study is an exploratory, qualitative case study. The participant is a child who stutters (CWS) that recently completed therapy. At discharge the child continued to stutter, but was deemed succ...
PCM-based High-density Thermal Storage Systems for Residential and Small Commercial Retrofit Applications

Abstract Environmental cooling loads comprise 11% of overall electric usage in the United States, and during peak cooling months in hot/humid climates these cooling loads can comprise more than 50% of peak electric energy loads. Thermal storage systems can shift these environmental cooling loads to non-peak hours, making better use of baseload generation capacity as well as reducing the need for expensive and environmentally inefficient peak power plants. Residential and small commercial buildings generate much of the cooling responsible for peak electric load, but these structures may not have the space or facilities to support conventional sensible energy thermal storage systems, such a chilled water thermal storage tanks. For these applications a compact, high-density, retrofittable thermal storage system is needed. This paper investigates the development, testing, and modeling of a compact, scalable PCM (phase change material) based latent thermal storage system for these applications. The results show that a simple tube-encapsulated, tetradecane PCM-based thermal storage system can reduce the size of a thermal store by at a factor of between 2 and 4 while providing acceptable energy recovery rates.
Feasibility and detection of a bio-inspired approach for space situational awareness

In nature, many biological species have devised motion strategies that help them with a variety of tasks, such as mating and foraging. One such phenomenon that has been recently studied in hoverflies involves a moving male hoverfly that conceals its motion from the viewpoint of a moving female hoverfly. The use of this bio-inspired strategy has also recently been considered in the context of Space Situational Awareness. In this paper, the feasibilities of applying the bio-inspired technique to free flying space vehicles are investigated. Furthermore, the detectability of the motion strategy is studied. Both the feasibilities and the detectability are investigated in the local vertical and local horizontal frame.
Rapid mass-spectrometric determination of boron isotopic distribution in boron carbide.

Abstract Boron isotopic ratios are measured in boron carbide by thermionic ionization mass spectrometry with no prior chemical separation. A powder blend of boron carbide and sodium hydroxide is prepared, a small portion is transferred to a tantalum filament, the filament is heated to produce sodium borate, and the filament is transferred to the mass spectrometer where the 11 B/ 10 B ratio is measured, using the Na 2 BO 2 + ion. Variables investigated for their effect on preferential volatilization of 10 B include the sodium hydroxide-boron carbide ratio and the temperature and duration of filament heating. A series of boron carbide pellets containing natural boron, of the type proposed for the control rods of the Fast Flux Test Facility reactor, were analysed with an apparently unbiased result of 4.0560 for the 11 B/ 10 B ratio (standard deviation 0.0087). The pellets contained over 3% metal impurities typically found in this material. Time of analysis is 45 min per sample, with one analyst.
169: Late preterm birth: an iatrogenic epidemic?

Objective: We evaluated whether the recorded indications for late preterm delivery were supported by generally accepted medical indications in a cohort of late preterm birth (LPTB). In addition, we compared neonatal outcomes in cases of LPTB with and without generally accepted medical indications. Methods: We conducted a retrospective cohort study of LPTB from 2007-2009 in two tertiary care centers and two community hospitals in Salt Lake City, UT. Subjects delivered a live born infant between 34-36 6/7 weeks’ gestation. Data were abstracted from maternal and neonatal medical records. An instrument created prior to data collection explicitly defined criteria for generally accepted medical indications for iatrogenic LPTB. Major neonatal morbidity was defined as a composite outcome of death in the first 120 days of life, intraventricular hemorrhage, necrotizing enterocolitis, and need for mechanical ventilation. Results: 244 cases of LPTB were analyzed. 18.9% of LPTB cases (46/244) did not meet criteria for a generally accepted medical indication for late preterm delivery. The recorded diagnoses ‘placenta previa’, ‘oligohydramnios’, ‘preeclampsia’, ‘maternal disease’, and ‘placental abruption’ were most likely to fail to meet criteria for generally accepted indication after review of primary medical records. LPTB without generally accepted medical indication was associated with an increased risk of composite major neonatal morbidity (19.1% vs. 7.9%, P = 0.03). Need for neonatal ventilator support was independently associated with LPTB without generally accepted medical indication (19.1% vs. 6.9%, P = 0.02). Conclusion: Almost one fifth of LPTB, and its neonatal sequelae, may be avoidable.
Geometry, mechanisms and significance of extensional folds from examples in the Rocky Mountain Basin and Range province, U.S.A

Abstract Geologic mapping and structural analysis in Paleogene half graben of Idaho and Montana have revealed over 70 extensional folds that form orthogonal sets with mostly NE- and SE-trending axes. On a regional scale they parallel or lie perpendicular to the strikes of the largest normal faults. Transverse folds, at a high angle to the fault, and folds oblique to the fault, comprise more than half of the folds and reflect the highly three-dimensional nature of the bulk strain. Detailed geometric analysis of 15 folds in the Salmon, Horse Prairie and Medicine Lodge basins shows that they typically have an upright to steeply inclined bisecting surface, an interlimb angle of 141°, and a plunge of 19°. Based on our synthesis of the eight common mechanisms of extensional folding and their distinguishing characteristics, we were able to determine how some of the investigated folds formed. Fault-bend folding above both fault-parallel and fault-perpendicular bends in the underlying normal fault produced most of the folds in the study area, but displacement gradients along normal faults, fault-drag, isostatic adjustments, and transtension were also factors in the deformation. Most of the compound folds, which result from more than one mechanism of folding, are oblique to all adjacent normal faults. Recognition of such extensional folds is critical, because they might be misinterpreted as contractional structures, they influence sediment thickness patterns and dispersal in rift basins, and may control the migration and trapping of petroleum and groundwater resources.
Single molecule correlation spectroscopy in continuous flow mixers with zero-mode waveguides

Zero-Mode Waveguides were first introduced for Fluorescence Correlation Spectroscopy at micromolar dye concentrations. We show that combining zero-mode waveguides with fluorescence correlation spectroscopy in a continuous flow mixer avoids the compression of the FCS signal due to fluid transport at channel velocities up to ~17 mm/s. We derive an analytic scaling relationship ∣δkONkON∣=∣δkOFFkOFF∣~kON+kOFFkON0.1DBDF−DBeSNR converting this flow velocity insensitivity to improved kinetic rate certainty in time-resolved mixing experiments. Thus zero-mode waveguides make FCS suitable for direct kinetics measurements in rapid continuous flow.
Thresholds of Emergence

Abstract Pascal’s wager implies the incommensurability of quality and quantity, but the emergence of new order with qualitatively unprecedented states upon the quantitative crossing of natural thresholds questions any simple dualism and points to special characteristics of time. The presence of natural thresholds requires that the universe cannot be understood in a purely analog fashion, as composed of smooth gradients analysable by probabilistic and statistical means. It must also be seen as constitutively granular and quantized, like the counters and turns of a game, and capable of unpredictable creativity. Mathematics implies a threshold between the computable and the uncomputable. Physics requires quanta and a distinction between the reversible and the irreversible. Chemistry dictates catastrophic changes of state. Evolutionary biology requires distinct competing individuals. Neuroscience requires the emergence of qualitatively irreducible cognitive capacities. Economic activity implies unpredictable financial crises. Information theory requires distinct signals distinguishable from noise. Freedom and responsibility, art and poetry can be understood in the light of threshold-crossing. American pragmatism, French evolutionary philosophy, chaos and complexity theory, game theory and the framework provided by J.T. Fraser’s work can guide future investigations of natural thresholds.
Drying Energy Conservation for Deep-Bed Barley-Malt Kilns

This study sought to reduce the thermal energy required to dry barley malt in deep-bed driers by controlling airflow and temperature, while holding drying time approximately constant and maintaining malt quality within acceptable limits. A malt drying model was employed to evaluate various temperature and airflow scenarios. Drying experiments were performed to determine the highest steady drying temperature which produced acceptable malt quality, and to validate model predictions. Results of the study showed that the numerical model closely predicted relative trends of malt drying variables under variable temperature and airflow conditions. Drying with the temperature held steady at 63 and 70°C, respectively, showed that the energy consumption was about 20% less at the higher temperature. Timed airflow reduction after the constant-rate drying period was predicted to reduce energy consumption. Gradually reducing airflow by 58% during the unsaturated drying period, while using a common drying temperature of about 83°C, reduced energy consumption by 19% when compared with a 25% airflow reduction typical of industrial drying. The resultant malt quality was equivalent and the drying time was unchanged.
Synthesis, [18F] radiolabeling, and evaluation of poly (ADP-ribose) polymerase-1 (PARP-1) inhibitors for in vivo imaging of PARP-1 using positron emission tomography

Imaging of poly (ADP-ribose) polymerase-1 (PARP-1) expression in vivo is a potentially powerful tool for developing PARP-1 inhibitors for drug discovery and patient care. We have synthesized several derivatives of benzimidazole carboxamide as PARP-1 inhibitors, which can be (18)F-labeled easily for positron emission tomographic (PET) imaging. Of the compounds synthesized, 12 had the highest inhibition potency for PARP-1 (IC50=6.3 nM). [(18)F]12 was synthesized under conventional conditions in high specific activity with 40-50% decay-corrected yield. MicroPET studies using [(18)F]12 in MDA-MB-436 tumor-bearing mice demonstrated accumulation of [(18)F]12 in the tumor that was blocked by olaparib, suggesting that the uptake of [(18)F]12 in the tumor is specific to PARP-1 expression.
Only the Illusion of Possible Collusion? Cheap Talk and Similar Goals: Some Experimental Evidence

Abstract Firms routinely engage in public communications that are available to various constituencies, including competitors. In a laboratory experiment with prisoner’s dilemma payoffs, the authors investigate the effect of one form of these communications—cheap talk signals: statements that are costless, nonbinding, and nonverifiable and do not directly affect the payoffs for either party. The authors find that only competitors that perceive that they share goals for a joint, coordinated outcome correctly update their beliefs about their competitor’s next move on the basis of cheap talk signals. The authors contend that the conditions for cheap talk to work may be so rare that cheap talk is more likely to fall on deaf ears than to result in collusion. The authors suggest implications for managers and public policymakers as well as areas for further research.
Conservative Design Rainfall Distribution

To design urban storm water infrastructures, hydrologists apply the SCS Types I, II, and III 24-h rainfall distribution curves to simulate the design rainfall hyetographs by which storm runoff can be predicted accordingly. Although SCS 24-h rainfall curves are recommended by the Natural Resources Conservation Service and have been widely adopted for many cosmopolitan areas in the United States, it is not enough to understand how these curves compare with observed data. In this study, a 57-year hourly rainfall data recorded in Denver was analyzed and then compared with the SCS 24-h rainfall curves. It is concluded that these SCS 24-h Types I and II curves do not represent the statistical average values. Rather, they represent the worst time distribution to form a severe storm. Using the concept of enveloping curves, conservative rainfall distributions can be derived using a similar approach as revealed by the SCS 24-h curves. The approach suggested in this study requires much less rainfall data than the statistical average.
A biophysical investigation of recombinant hemoglobins with aromatic B10 mutations in the distal heme pockets.

This study examines the structural and functional effects of amino acid substitutions in the distal side of both the α- and β-chain heme pockets of human normal adult hemoglobin (Hb A). Using our Escherichia coli expression system, we have constructed four recombinant hemoglobins: rHb(αL29F), rHb(αL29W), rHb(βL28F), and rHb(βL28W). The α29 and β28 residues are located in the B10 helix of the α- and β-chains of Hb A, respectively. The B10 helix is significant because of its proximity to the ligand-binding site. Previous work showed the ability of the L29F mutation to inhibit oxidation. rHb(αL29W), rHb(βL28F), and rHb(βL28W) exhibit very low oxygen affinity and reduced cooperativity compared to those of Hb A, while the previously studied rHb(αL29F) exhibits high oxygen affinity. Proton nuclear magnetic resonance spectroscopy indicates that these mutations in the B10 helix do not significantly perturb the α1β1 and α1β2 subunit interfaces, while as expected, the tertiary structures near the heme pockets are ...
Evidence for simple genetic control of a fruit-colour polymorphism in Acacia ligulata

Fruit-colour polymorphisms are common in nature, but their genetic bases have rarely been examined in wild species. Here, I report on controlled crosses in Acacia ligulata A.Cunn. ex Benth., an Australian arid-zone shrub with a red–yellow–orange aril colour polymorphism. The evidence is consistent with 1-locus, 2-allele control of red v. yellow phenotypes; these phenotypes comprise 98.7% of the adult plants in nature. At this proposed r locus, yellow is dominant to red. Evidence concerning the rare orange morph is limited, but is consistent with models in which orange is produced by either (a) a third allele at the r locus or (b) modification by a second locus. Simple genetic architecture for ecologically relevant traits, such as fruit colour, should aid in linking ecological processes such as frugivory and seed dispersal to the evolutionary trajectories of plant populations.
Categories of Competition

In the first part of this paper, I argue that philosophers of sport have mistakenly privileged a specific psychology and purpose in their definitions of competition. The result of this mistake has been that philosophers of sport make generalisations about competition as such which in fact only hold for some competitions. In the second and third parts of the paper, I articulate an alternative approach: rather than search for a single psychology and purpose that underlies all competition, I argue that we should begin by acknowledging four distinctly different competitive formats, and only then enquire as to which psychologies and purposes are more or less appropriate to each format. This method allows us to capture the richness and diversity of competition, and helps to ensure that we do not confuse part and whole when defining it.
A linear model for gauss elimination

This paper presents the detailed development of a linear model for the computed solution to the linear system Ax = b; this model consists of an initial transcribing error plus a random part to model round-off. Discussed are general implications and techniques for the appli-cation of the model towards diminishing the effects of both.
The N-terminal region is important for the allosteric activation and inhibition of the Escherichia coli ADP-glucose pyrophosphorylase.

The ADPglucose pyrophosphorylase (EC 2.7.7.27) from Escherichia coli is allosterically activated by fructose 1,6-bisphosphate and inhibited by AMP. Proteolysis of the enzyme with proteinase K causes loss of activity and generates two peptides, 21 and 28 kDa, from the 49.7-kDa subunit. The presence of ADPglucose, Mg2+, and fructose 1, 6-bisphosphate during the incubation with proteinase K protected the enzyme activity and prevented cleavage at sites Met181-Ala182 and Phe192-Val193. Proteolysis of the protected enzyme removed 10 to 13 amino acids from the N-terminal and 2 amino acids from the C-terminal. The resulting enzyme was almost independent of the need for fructose 1,6-bisphosphate for maximal activity and insensitive to inhibition by AMP. The apparent affinity for the substrates was similar to that of the fully-activated wild-type enzyme. These data suggest that amino acid residues in the N-terminal portion and possibly the C-terminal portion of ADPglucose pyrophosphorylase are part of the regulatory domain of the enzyme, critical for allosteric regulation of the enzyme.
Geography of photoperiodic response in diapausing mosquito.

IN temperate latitudes, many arthropods rely on photoperiod to cue their seasonal development. Although the relationship between critical photoperiod and latitude is well illustrated, that between critical photoperiod and altitude remains obscure1,2. I wish to consider photoperiodic control of dormancy in the pitcher-plant mosquito, Wyeomyia smithii, and quantify the relative effects of altitude and latitude on the photoperiodic response of an organism.
Rapid Eye Movements and Dream Imagery: Are they Related?

IT has been suggested that patterns of physiological activity during rapid eye movement (REM) sleep are directly related to concurrent dream experiences1–4. Roffwarg et al.4 reported a correspondence between REM patterns and visual imagery in 70–80 per cent of vivid dream reports, and concluded that the REMs represent scanning responses of the visual dream images. Thus visually “active” dreams are associated with more REM activity than are “passive” dreams involving little visual activity2,5.
Mechanisms of Protection of Cationic Lipid‐DNA Complexes During Lyophilization

Gene therapy using nonviral vectors offers advantages over viral methods. However, the instability of aqueous suspensions of cationic lipid-DNA complexes is a major problem that must be overcome to develop this therapeutic modality on a pharmaceutical scale. Disaccharides have been reported to protect lipid-DNA complexes during lyophilization, and recovery of transfection correlates with the retention of particle size. However, the mechanism by which disaccharides achieve this protection is not known. The purpose of this study was to investigate the protective mechanism by lyophilizing cationic lipid-DNA complexes with a variety of solutes that have different physical behaviors during the lyophilization process. In agreement with previous studies, disaccharides conferred protection to lipid-DNA complexes. By contrast, a large polymeric sugar, hydroxyethyl starch, did not protect as well. The level of protection by additives, such as mannitol, that crystallized during lyophilization was also less than that of the disaccharides, but some protection was nonetheless observed. These data suggest that water replacement plays a significant role in protecting complexes during lyophilization. A second mechanism that prevents aggregation by diluting complexes within freeze-concentrated solutions or dried cakes may also contribute to protection. Sample vitrification did not correlate with maintenance of transfection efficiency. Elucidation of the mechanism(s) by which cationic lipid-DNA complexes are protected during lyophilization will permit a rational approach to the development of stable, lyophilized formulations.
Robust servomechanism output feedback controllers for feedback linearizable systems

Abstract We consider a single-input-single-output nonlinear system which has a uniform relative degree equal to the dimension of the state vector. The system can be transformed into a normal form with no zero dynamics. We allow the system's equation to depend on bounded uncertain parameters which do not change the relative degree. Disturbances are assumed to satisfy a strict-feedback condition which allows us to use a time-varying, disturbance-dependent transformation to transform the system into an error space where disturbances and uncertainties satisfy the matching condition. The nonlinear functions in the error space are used to choose an internal model which is augmented with the system, and a robust state feedback control is designed to drive the error to a positively invariant set that contains the origin. We then show the existence of a zero-error manifold inside this set which attracts all trajectories inside the set. To implement this control using output feedback, we saturate the state feedback control outside a compact set of interest and estimate the state using a high-gain observer. The output feedback controller recovers the robustness and asymptotic tracking properties of the state feedback controller.
Design and evaluation of a nanoscale differential tensile test device for nanofibers

The development of nanofibers could open new avenues in fundamental research and novel applications. Tensile properties of these nanofibers are a good indicator of their overall mechanical response. However, accurate measurements of tensile properties at the micro- and nanoscales remain a challenge. Here we report a simple but highly efficient differential nanoscale tensile test device constructed from off the shelf state-of-the-art components. The unique feature of this device is that it can measure the applied load and specimen’s deformation in the nanonewton and nanometer scales, respectively. First experimental results on electrospun nanofibers are reported.
Bilinear signal synthesis in array processing

Multiple source signals impinging on an antenna array can be separated by time-frequency synthesis techniques. Averaging of the time-frequency distributions (TFDs) of the data across the array permits the spatial signatures of sources to play a fundamental role in improving the synthesis performance. Array averaging introduces a weighting function in the time-frequency domain that decreases the noise levels, reduces the interactions of the source signals, and mitigates the crossterms. This is achieved independent of the temporal characteristics of the source signals and without causing any smearing of the signal terms. The weighting function may take noninteger values, which are determined by the communication channel, the source positions, and their angular separations. Unlike the recently devised blind source separation methods using spatial TFDs, the proposed method does not require whitening or retrieval of the source directional matrix. The paper evaluates the proposed method in terms of performance and computations relative to the existing source separation techniques based on quadratic TFDs.
Mechanisms and kinetics of precipitate restructuring during irradiation

Abstract Irradiations were performed at temperatures from 400 to 700°C using 3.0-MeV 58 Ni + ions in order to investigate γ'-precipitate restructuring in two model alloys: Ni-12.8 at% Al and Ni-12.7 at% Si. The precipitates coarsened, with the third power of the average diameter proportional to the damage dose. The temperature dependence of the rate constants for irradiated specimens is described in terms of a modified Lifschitz-Slyozov-Wagner coarsening model that includes radiation-enhanced diffusion. Redistribution of precipitate by enhanced precipitation (Ni-Si) or precipitate dissolution (Ni-Al) at point-defect sinks caused maxima in γ' size with dose. Precipitate redistribution at the free surfaces of irradiated thin foils and at γ/γ' particle interfaces is described.
X-ray absorption in valence-excited molecules as a possible contrast mechanism for chemically sensitive imaging and spectroscopy.

A pump-probe technique, x-ray inverse fluorescence allowed by molecular excitation (XIFAME), is proposed as a contrast mechanism for x-ray microscopy. The technique consists of using a laser to produce holes in the valence levels of selected molecules; these holes then permit inverse fluorescent absorption transitions to occur. The method would permit the selective mapping of simple molecular structures and oxidation states of light elements. Cross-section estimates are made, and it is argued that the technique is potentially more sensitive than imaging techniques based on the atomic absorption edge. It is also argued that XIFAME has advantages over the use of x-ray-absorption near-edge structure for spectroscopic measurements of very dilute molecular structures.
Computing dispersion interactions in density functional theory

Abstract In this article techniques for including dispersion interactions within density functional theory are examined. In particular comparisons are made between four popular methods: dispersion corrected DFT, pseudopotential correction schemes, symmetry adapted perturbation theory, and a non-local density functional — the so called Rutgers–Chalmers van der Waals density functional (vdW-DF). The S22 benchmark data set is used to evaluate the relative accuracy of these methods and factors such as scalability and transferability are also discussed. We demonstrate that vdW-DF presents an excellent compromise between computational speed and accuracy and lends most easily to full scale application in solid materials. This claim is supported through a brief discussion of a recent large scale application to H2 in a prototype metal organic framework material (MOF), Zn 2 BDC 2 TED. The vdW-DF shows overwhelming promise for first-principles studies of physisorbed molecules in porous extended systems; thereby having broad applicability for studies as diverse as molecular adsorption and storage, battery technology, catalysis and gas separations.
Syria and the Olympics: National Identity on an International Stage

Since its independence in 1946, Syria has fielded a team for every summer Olympic competition except 1956, yet has won only three Olympic medals. In contrast with its smaller, higher-powered neighbour Lebanon, its participation at the Olympics has been consistent but limited, with the country making little impact internationally. Yet the history of Syria's involvement with the Olympics reflects key elements of its political and social history: its ambitious but short-lived partnership with Egypt, the Baathist-supported promotion of women as athletes and head of the National Olympic Committee and its commitment to participation in the vexed but ideologically important Pan-Arab Games. This article uses official International Olympic Committee publications and related press coverage to examine the history of Syria's involvement with the Olympic Games, the Mediterranean Games and the Pan-Arab Games. It argues that Syria's participation was initially important not for its medal count but for the ‘sign of state...
Fluorescence analysis of picoliter samples

Abstract The fluorescence intensity of picoliter-volume samples was quantitated by taking samples and standards into a single siliconized capillary, fixing the capillary under the objective of a microscope-fluorometer, and defining an effective “fluorescence chamber” within the capillary by placing an imaging diaphragm in the emission path. Samples were then moved, by pneumatic control with an air syringe, within the capillary to this “fluorescence chamber.” A diaphragm in the excitation path limited the volume of sample excited. Fluorescence from all samples was thus directly determined under identical optical conditions. The co-efficient of variation of replicate measurements was 3%; carry-over from sample to sample within the capillary was less than 2%. A 3-pl sample containing 0.3 amol of sodium fluorescein (about 200,000 molecules) could be discriminated from the background; fluorescence intensity was linear with concentration for three to four orders of magnitude. Fluorescence intensities of NADH and an ammonia- o -phthalaldehyde-thiol adduct were also determined. Using this “fluorescence chamber” allowed straightforward scaling down of a fluorescence assay for urea in 20-pl samples, lowering the limit of detection to 10 fmol, three orders of magnitude below a previously reported microscale assay. This technique is applicable to many fluorescence assays used in studies of cell physiology, and should allow routine measurement of metabolites in individual cells or of enzymes in individual subcellular organelles.