cssi/SciSciGPT-SciSciNet huggingface dataset:
Defining a Discretized Space Suit Surface Radiator With Variable Emissivity Properties

Heat rejection for space suit thermal control is typically achieved by sublimating water ice to vacuum. Converting the majority of a space suit's surface area into a radiator may offer an alternative means of heat rejection, thus reducing the undesirable loss of water mass to space. In this work, variable infrared (IR) emissivity electrochromic materials are considered and analyzed as a mechanism to actively modulate radiative heat rejection in the proposed full suit radiator architecture. A simplified suit geometry and lunar pole thermal environment is used to provide a first-order estimate of electrochromic performance requirements, including number of individually controllable pixels and the emissivity variation that they must be able to achieve to enable this application. In addition to several implementation considerations, two fundamental integration architecture options are presented—constant temperature and constant heat flux. With constant temperature integration, up to 48 individual pixels with an achievable emissivity range of 0.169–0.495 could be used to reject a metabolic load range of 100 W–500 W. Alternatively, with constant heat flux integration, approximately 400 pixels with an achievable emissivity range of 0.122–0.967 are required to reject the same load range in an identical external environment. Overall, the use of variable emissivity electrochromics in this capacity is shown to offer a potentially feasible solution to approach zero consumable loss thermal control in space suits.
Morphogenetic Events Associated with Stolon Elongation in Colonial Hydroids

The growth of stolons anil the development of hydranths in thecate hydroids (Cnidaria, Hydrozoa) have several common features. In both the terminal zone shows rhythmic pulsations which accompany periodic advances and withdrawals of the tip. Behind the terminal zone is a longer region of coenosarc which shows vigorous contractions, and these produce flow of the contents of the gastrovascular cavity. These contractions are not directly related to the movement of the tips of pedicels and stolons, nor are they related to contractions within a developing hydranth. The growing regions are not pushed out from behind, but figuratively pull more proximal tissue along. The changes in shape must involve active changes within the cells. The terminal cells are not “typical” myoepithelial cells (with “muscle tails”). How they alter their shape is not yet known. Evidence from dissociation studies and from treatment with drugs indicates a critical stage in hydranth development before which tissues are indeterminate, after which a mosaic of the hydranth is established.
Technology standards-setting in the US wireless telecommunications industry: A study of three generations of digital standards development

This article focuses on the evolution of technology standards-setting in the US wireless telecommunications industry during the decades of the 1980s and 1990s. The purpose of this exploratory study is to understand and model the organizational process and environmental influences employed to develop three generations (i.e. second generation (2.0) Time Division Multiple Access (TDMA), second generation (2.5) Code Division Multiple Access (CDMA), and third generation (3.0) Wideband Code Division Multiple Access (WCDMA)) of de jure US wireless digital telecommunications standards. Through the use of a multi-case study approach, the research study focuses on inter-organizational strategic cooperation among wireless telecommunications firms proposing competitive technology designs in the standard development process. Based on data collected in these three case studies, wireless standard development models are ''mapped'' for the TDMA, CDMA and WCDMA technologies. Moreover, a generic, conceptual wireless technology standard development model is ''mapped'', a further refinement of an earlier seminal model of telecommunications standard-setting. Finally, conclusions are reached, with both theoretical and practical implications, and suggested areas of future research (in the form of a set of research hypotheses) are presented.
Long-term central IV access in patients with mitochondrial disease.

Mitochondrial disease results from alteration in genes that control mitochondrial function. Patients with this disease present with multisystem organ involvement that may include gastrointestinal (GI) tract dysfunction, including obstruction, pseudo obstruction, bowel infarction and malabsorption syndromes. For this reason, care of this population may require long-term central intravenous (IV) access for administration of hyperalimentation, fluid, medications and blood products. Additionally, these patients may be immunosuppressed and at risk of sepsis. With vulnerability across many organ systems, symptom exacerbation can result from any physiological, psychological, or environmental stressor. There is no cure for mitochondrial disease, and quality-of-life goals are paramount. If GI tract dysfunction develops, treatment may require high-acuity level home care that includes the use of a central IV access device. This article presents an overview of this challenging population, and a plan for safe and effe...
Collisional time‐correlation functions for molecular interactions

Collisional time-correlation functions (TCFS) combine methods of scattering theory and of many-body theory to describe the interaction of projectiles with complex targets. In recent work, we have developed the theory of collisional TCFS for molecular interactions using multiple scattering expansions, semiclassical approximations and operator algebras. The theory has been applied to atomic collisions with molecules, to calculate cross sections and compare them with experiment.
Relative growth of different species of marine algae in wasterwater-seawater mixtures

In recent studies, we developed a combined nutrient removal-marine aquaculture process for the tertiary treatment of wastewater and the production of commercially important shellfish. Part of this process consists of an outdoor mass cultivation system for marine algae. During our previous experiments we observed that marine diatoms almost exclusively are the dominant algal species in our outdoor cultures. To better understand this phenomenon of diatom dominance we grew 16 species of marine algae in continuous monoculture under laboratory conditions simulating to some degree the conditions prevailing in our outdoor experiments. Species such as Skeletonema costatum, Monochrysis lutheri and Tetraselmis sp., which were never dominant in our outdoor cultures, grew as well in monoculture, as Phaeodactylum tricornutum, frequently, the prevalent species outdoors. However, when monocultures of Dunaliella tertiolecta and Thalassiosira pseudonana (3H) were purposely contaminated with P. tricornutum, the latter species quickly became dominant. It is suggested that a complex interaction of environmental factors is usually responsible for the dominance of a particular species; one such factor may be the nitrogen source in the growth media. Under conditions of virtually, complete nitrogen assimilation, the carbon: nitrogen ratio in the algae was high (7 to 8) when NO 3 - −N was the source of nitrogen, and low (4 to 6) when NH 4 + −N was the prime form of nitrogen. When algal growth was low, resulting in a large inorganic nitrogen residue, the carbon:nitrogen ratio was low regardless of whether NO 3 - −N or NH 4 + −N was the main nitrogen source.
Flâneur Smellscapes in Le Spleen de Paris

AbstractThe figure of the flâneur haunts the pages of Charles Baudelaire’s Le Spleen de Paris. As first-person narrator, man, woman, protagonist, or passer-by, the flâneur presence lends continuity to this collection of fifty seemingly disparate prose poems. The flâneur has also become almost inseparable from the backdrop of the city and its streets, which in mid-nineteenth-century Paris were crowded, muddy, and smelly. The purpose of this essay is to rethink the Baudelairean flâneur, and the prose poems, through olfactory perception. Odours inhabit intimate spaces and invade public environments, thus facilitating a process of mutual permeation, or, to use a word favoured in Baudelaire’s writing, a mutual penetration. An analysis of both the theory and practice of flânerie in the prose poems reveals that smell and flânerie function similarly as experiences of volatility, transience, intimation, and penetration in Le Spleen de Paris. Here textual references to the olfactory go beyond mimetic realism, contr...
Taking anti-depressant medications: Resistance, trial commitment, conversion, disenchantment

This paper documents the meanings attached to taking anti-depressant medications. Indepth interview materials from a sample of persons diagnosed and treated for depression suggest that taking doctor-prescribed drugs involves an extensive interpretive process about the meanings of having an emotional “illness.” The data and analysis extend previous studies on the meanings of taking psychotropic drugs by showing how those meanings change over the course of the depression “career.” An individual's changing responses to psychiatric medications can be described as a socialization process having radical implications for self definition. The four stages constituting this socialization process and central to the analysis in the paper are: resistance, trial commitment, conversion, and disenchantment. Each of these stages is discussed in terms of its impact on personal identity. The implications of the presented data for challenges to the medical model are discussed.
GENERAL AND DIFFERENTIAL BEHAVIORAL EFFECTS OF FIVE ETHANOL DOSAGES ON THE ALBINO RAT

Investigation of immediate behavioral effects of 5 ethanol dose levels on 30 albino rats was undertaken. Each dose-level group had 5 Ss, with each S on a different water-deprivation schedule. Behavioral indices included respiration, balance, muscle tonus, auditory sensitivity, activity, coordination, and dose-effect length. Low doses resulted in a stimulative effect, while larger doses produced increasing incapacitation of caudorostral progression, with the highest dose of ethanol producing unconsciousness.
A century of hybridization: Decreasing genetic distance between American black ducks and mallards

American black ducks (Anas rubripes) and mallards (A. platyrhynchos) are morphologically and behaviorally similar species that were primarily allopatric prior to European colonization of North America. Subsequent sympatry has resulted in hybridization, and recent molecular analyses of mallards and black ducks failed to identify two distinct taxa, either due to horizontal gene flow, homoplasy, or shared ancestry. We analyzed microsatellite markers in modern and museum specimens to determine if the inter-relatedness of mallards and black ducks was an ancestral or recent character. Gst, a measure of genetic differentiation, decreased from 0.146 for mallards and black ducks living before 1940, to 0.008 for birds taken in 1998. This is a significant reduction in genetic differentiation, and represents a breakdown in species integrity most likely due to hybridization. Using modern specimens, we observed that despite a lower incidence of sympatry, northern black ducks are now no more distinct from mallards than their southern conspecifics.
Gas liquid and thin layer chromatographic analysis of 12-aminostearic acid.

Products from the reductive amination of 12-ketostearic acid to 12-aminostearic acid have been monitored by gas liquid chromatography (GLC) and thin layer chromatography (TLC). The nonvolatile amino acid was analyzed by TLC, but its trifluoroacetylated methyl ester was analyzed by TLC and GLC. Conditions for obtaining high conversions of the amino acid to this derivative are described. The derivative was quantitated by GLC using methyl 12-ketostearate as an internal standard. Various developing solvents, types of TLC plates, and visualization spray reagents were examined and compared for efficiency and convenience regarding the TLC separations. Satisfactory TLC systems were developed for crude reaction mixtures containing 12-aminostearic acid and these same mixtures, which were trifluoroacetylated. The influence of water in the developing solvent on the ionic forms of the amino acid is discussed.
The sorting index and equidistribution of set-valued statistics over restricted permutations

Abstract We prove that the pairs of permutation statistics ( sor , Cyc ) and ( inv , Rmil ) are equidistributed on the set of permutations that correspond to arrangements of n non-atacking rooks on a fixed Ferrers board with n rows and n columns and give their generating functions. Our results extend recent results of Petersen. The key elements in the proofs are the A-code and the B-code introduced by Foata and Han. We show that the map B-code − 1 ∘ A-code is a bijection on the set of restricted permutations which sends inv to sor, Rmil to Cyc and preserves the set-valued statistics Lmal and Lmap. We also show analogous equidistribution results for restricted permutations of type B and D by constructing appropriate A-codes and B-codes in each case.
Self-organization in the initiation of adiabatic shear bands

The radial collapse of a thick-walled cylinder under high-strain-rate deformation ({approximately}10{sup 4} s{sup {minus}1}) was used for the investigation of shear-band initiation and pattern development in titanium. Experiments were carried out in which the collapse was arrested in two stages, in order to observe the initiation and propagation of shear bands. The occurrence of shear bands to accommodate plastic deformation in response to external tractions is a collective phenomenon, because their development is interconnected. The bands were observed to form on spiral trajectories and were periodically spaced. The spacing of the shear bands decreased with the progression of collapse, and was equal to approximately 0.6 mm in the final stage of collapse. The shear-band spacing was calculated from two existing models, based on a perturbation analysis and on momentum diffusion. Values of 0.52 and 3.3 mm were obtained with material parameters from quasi-static and dynamic experiments. The predictions are found to give a reasonable first estimate for the actual spacings. The detailed characterization of the shear-band front leads to an assessment of the softening mechanisms inside a shear localization region. The initiation of localization takes place at favorably oriented grains and becomes gradually a continuous process, leading eventually to dynamicmore » recrystallization.« less
The relative wavelengths of fast and slow velocity anomalies in the lower mantle: Contrary to the expectations of dynamics?

Abstract We quantify the spherical harmonic characteristics of shear velocity anomalies as a function of depth for a range of tomographic models of the Earth's mantle. In particular, the amplitude spectra of fast and slow anomalies are analyzed separately. Thus, the higher amplitude harmonic degrees and relative scale lengths of both possible thermal upwellings and downwellings can be determined. Our results are consistent with prior studies in that we find that the amplitude spectra of heterogeneity (fast and slow) in the mid-mantle are essentially flat. However, where heterogeneity is known to be stronger in the deep mantle, slow anomalies are observed to be consistently higher amplitude at harmonic degrees 1–12, while fast anomalies dominate at higher degrees. This result is at odds with many dynamic models in which upwellings tend to be narrow and downwellings tend to be broad. This inconsistency with isochemical dynamic models may be associated with variations in phase, chemistry and/or viscosity in the Earth's lowermost mantle. The technique presented here provides a means for discriminating between these effects when comparing tomographic and dynamic models of the Earth's mantle.
Deficient acquisition and retention of a visual-tactile discrimination task in rats with medial thalamic lesions

Seven hooded rats with electrolytic lesions centered in the dorsal medial nucleus of the thalamus and nine sham-operated animals were given a postoperative reacquisition-retention test of a preoperatively acquired compound stimulus, visual-tactile, discrimination problem. Also, 10 rats with the same lesion and eight animals with sham operations were tested for postoperative acquisition of the same discrimination problem. The animals with thalamic lesions were found to be deficient relative to the sham-operated animals on both retention and acquisition of the discrimination task. Tests for maze activity, food consumption, and visual placing response failed to produce any evidence for differences between the thalamically damaged and sham-operated animals.
The Human Mycobiome and its Impact on Health and Disease

Until recently, the human microbiome was synon- ymous with the bacterial community. Fortunately, recent stud- ies have shown that the human microbiome is complex and composed of bacteria, fungi and viruses. Characterizing the fungal community "mycobiome" in health (involving oral cavity, skin, and gastrointestinal tract body sites) is paving the way to defining the changes that this community un- dergoes in disease. Although the number of studies investi- gating the mycobiome in disease is small, findings from these investigations are exciting and beginning to show that fungi, apart from their role as normal flora or direct pathogens, may aggravate disease symptoms in specific patient populations (e.g., inflammation in patients with ulcerative colitis). Such unexpected findings provide impetus for the conduct of re- search aimed at elucidating the role of the fungal community, and its interactions with other microbial communities, in immunocompromised diseases. Funding of these research efforts is warranted.
Gas-phase hydrogen/deuterium exchange of 5′- and 3′-mononucleotides in a quadrupole ion trap: Exploring the role of conformation and system energy

Gas-phase hydrogen/deuterium (H/D) exchange reactions for deprotonated 2′-deoxy-5′-monophosphate and 2′-deoxy-3′-monophosphate nucleotides with D2O were performed in a quadrupole ion trap mass spectrometer. To augment these experiments, molecular modeling was also conducted to identify likely deprotonation sites and potential gas-phase conformations of the anions. A majority of the 5′-monophosphates exchanged extensively with several of the compounds completely incorporating deuterium in place of their labile hydrogen atoms. In contrast, most of the 3′-monophosphate isomers exchanged relatively few hydrogen atoms, even though the rate of the first two exchanges was greater than observed for the 5′-monophosphates. Mononucleotides that failed to incorporate more than two deuterium atoms under default reaction conditions were often found to exchange more extensively when reactions were performed under higher energy conditions. Integration of the experimental and theoretical results supports the use of a relay exchange mechanism and suggests that the exchange behavior depends highly on the identity and orientation of the nucleobase and the position and flexibility of the deprotonated phosphate moiety. These observations also highlight the importance of the distance between the various participating groups in addition to their gas-phase acidity and basicity.
Blood lead levels and bone turnover with weight reduction in women

High bone turnover states are known to raise blood lead levels (BPb). Caloric restriction will increase bone turnover, yet it remains unknown if weight reduction increases BPb due to mobilization of skeletal stores. We measured whole blood Pb levels ((206)Pb) by inductively coupled plasma mass spectrometry in 73 women (age 24-75 years; BMI 23- 61 kg/m(2)) before and after 6 months of severe weight loss (S-WL), moderate weight loss (M-WL), or weight maintenance (WM). Baseline BPb levels were relatively low at 0.2-6.0 microg/dl, and directly associated with age (r=0.49, P<0.0001). After severe WL (-37.4+/-9.3 kg, n=17), BPb increased by 2.1+/-3.9 microg/dl (P<0.05), resulting in BPb levels of 1.3-12.5 microg/dl. M-WL (-5.6+/-2.7 kg, n=39) and WM (0.3+/-1.3 kg, n=17) did not result in an increase in BPb levels (0.5+/-3.2 and 0.0+/-0.7 microg/dl, M-WL and WM, respectively). BPb levels increased more with greater WL (r=0.24, P<0.05). Bone turnover markers increased only with severe WL and were directly correlated with WL. At baseline, higher calcium intake was associated with lower BPb (r=-0.273, P<0.02), however, this association was no longer present after 6 months. Severe weight reduction in obese women increases skeletal bone mobilization and BPb, but values remain well below levels defined as Pb overexposure.
Physician as patient. The example of coronary angioplasty

Abstract The outcome and behavior of 43 consecutive physicians undergoing percutaneous transluminal coronary angioplasty were compared to those of 43 control patients (non-physicians) matched for sex, arteries attempted, and time of intervention. As for baseline characteristics, the groups were similar but fewer physicians smoked or took beta-blockers and fewer control patients took calcium-blockers. The immediate outcome of both groups showed no significant differences. The in-hospital management was not different either except that physicians complained more often about pain than control patients. Complaints about care or complaints of the nursing personnel about patients were found with equal frequency in both groups. The saying that "physicians are the worst patients" could not be substantiated in the example of coronary angioplasty, yet neither were their care and outcome superior to those of control patients.
Reliability analysis for aircraft generators

EVER-INCREASING reliability wherever economically justifiable long has been an important objective for the designers of all electric equipment. Rough yardsticks ? such as service life, maintenance costs, and complaint charges ? have been used as measures of success in the attainment of this objective, but precise, quantitative indices of reliability have been lacking in many cases. This lack of emphasis on the quantitative evaluation of product reliability may have been justifiable in the past, but the situation is changing rapidly. In particular, components for aircraft and missile applications will be required more and more frequently to attain specified levels of reliability. This will be necessary because performance requirements in such applications require that components be pushed to the extremes of their capabilities. In addition, the dollar and time investment required to bring a modern, air-borne weapons systems to an operational status, coupled with the vital importance of such systems performing their assigned tasks, makes it imperative that all components not only meet specified performance standards, but that they do so reliably and consistently.
SELF-ORGANIZING AGENT-BASED GRADE TRANSITION IN DISTRIBUTED CHEMICAL REACTOR NETWORKS

Abstract Agent-based control structures provide flexible and emergent solutions to complex nonlinear problems benefiting from properties such as modularity, adaptability, scalability and robustness. One such problem is product grade transitions in distributed process. The framework proposed earlier (Tetiker, 2006a) is extended by adding several layers of agents to control species percentage distribution in autocatalytic reactor networks. A deadlock detection layer is implemented to detect and solve conflicting cases between local controller agents. An auctioning mechanism is employed to promote competition between local controller agents leading to emergent solutions satisfying global constraints. The proposed architecture performed successfully to change the species percentage distributions without specifying the final configuration.
Rit Subfamily Small GTPases: Regulators in Neuronal Differentiation and Survival

Ras family small GTPases serve as binary molecular switches to regulate a broad array of cellular signaling cascades, playing essential roles in a vast range of normal physiological processes, with dysregulation of numerous Ras-superfamily G-protein-dependent regulatory cascades underlying the development of human disease. However, the physiological function for many "orphan" Ras-related GTPases remain poorly characterized, including members of the Rit subfamily GTPases. Rit is the founding member of a novel branch of the Ras subfamily, sharing close homology with the neuronally expressed Rin and Drosophila Ric GTPases. Here, we highlight recent studies using transgenic and knockout animal models which have begun to elucidate the physiological roles for the Rit subfamily, including emerging roles in the regulation of neuronal morphology and cellular survival signaling, and discuss new genetic data implicating Rit and Rin signaling in disorders such as cancer, Parkinson's disease, autism, and schizophrenia.
Dynamics of Tropical Low-Frequency Waves: An Analysis of the Moist Kelvin Wave

Abstract Stability of the equatorial atmosphere to a quasi-zonal, low frequency (order of 10−6 s−1) disturbance is investigated, using a model that consists of a two-layer free atmosphere and well-mixed boundary layer. The inclusion of boundary layer convergence leads to a circulation-dependent heating more nearly in accord with the behavior of numerically simulated low-frequency waves. Slowly eastward moving unstable waves were found in a parameter regime stable to inviscid wave-CISK. The instability depends crucially upon the vertical distribution of the moist static energy of the basic state. A derived instability criterion suggests that amplification occurs when the condensational heating supported jointly by interior wave convergence and frictional convergence dominates over the dissipations due to longwave radiation and boundary layer viscosity. The unstable waves exhibit preferred planetary scales. Since the vertical distribution of moist static energy of the basic state is closely related to sea s...
Two sides of the same coin.

Dramatically different mutant phenotypes usually reflect mutations in different genes, but this is not necessarily so, especially when microRNA regulation is involved. A beautiful example of this now comes from the discovery of the maize microRNA tasselseed4 and its target ids1/Tasselseed6, which uncovers a new facet in the control of inflorescence branching and sex determination in flowers.
Alkaline Lyotropic Silicate−Surfactant Liquid Crystals

Multinuclear (2H, 13C, 29Si, 81Br) magnetic resonance spectroscopy, small-angle X-ray scattering, and polarized optical microscopy techniques have been used to investigate molecular and mesoscopic organization in silicate−surfactant lyotropic liquid crystals with hexagonal and lamellar morphologies under highly alkaline conditions. Such systems cooperatively self-assemble following the addition of a basic aqueous solution containing anionic silicate oligomers (e.g., double-four-ring species) to an isotropic micellar solution of cationic surfactant molecules (e.g., cetyltrimethylammonium bromide). Important similarities and differences are shown to exist between multicomponent silicate−surfactant and conventional binary lyotropic liquid crystals. Under highly alkaline conditions, the silicate−surfactant systems possess the characteristics of ordinary lyotropic liquid crystalline systems, though the balance of forces underlying their self-assembly is complicated by the richness of the aqueous silicate chemi...
Acceptance Criteria for Ultratrace HPLC-Tandem Mass Spectrometry: Quantitative and Qualitative Determination of Sulfonylurea Herbicides in Soil.

Eight commonly used sulfonylureas (SUs: nicosulfuron, thifensulfuron methyl, metsulfuron methyl, sulfometuron methyl, chlorsulfuron, bensulfuron methyl, tribenuron methyl, and chlorimuron methyl) and deuterium-labeled nicosulfuron (nicosulfuron-d6), used as an internal standard, were isolated from soil by solvent extraction and identified under quantitative and qualitative ion spray LC/MS/MS conditions using the selected reaction monitoring (SRM) mode of acquisition. The lower level of quantitation for these SUs in soil was determined at the 0.05 ppb level using a TurboIonSpray adapted LC/MS interface without a precolumn split and optimizing MS/MS tuning conditions for individual SUs. The eight SUs were qualitatively identified and quantitatively determined in soil. The standard curve for each SU was linear from 0.05 to 10 ppb. This SRM LC/MS method demonstrates high sensitivity and high specificity for these SUs in soil and shows at least a 400-fold improvement in sensitivity over previous reports. Acce...
Diffusion of adsorbate atoms on the reconstructed Si(111) surface

Abstract We study the adsorption and diffusion of foreign atoms with different valences (K, Mg, Ga, Ge) on the reconstructed Si(111) surface using density functional theory total-energy calculations. We find that the stable adsorption sites for all the adsorbate atoms considered are high-coordination surface sites (T4-type, H3-type or B2-type) rather than the surface dangling bond sites (T1 or adatom T4 site) as might have been expected from simple bond-counting arguments. We also examine the surface diffusion paths and find that the adsorbate atoms, depending on their interaction with the surface, experience certain restrictions in their motion which we refer to as “intermittent diffusion”. These results help elucidate a number of experimental observations.
The morphology and syntax of Ulster Scots

Ulster differs from the other three historical provinces of Ireland in the presence of Ulster Scots, an off-shoot of Lowland Scots brought principally from the Western and Central Lowlands of Scotland in the 17th century through a plantation established by King James I and through periodic migrations, especially in times of economic duress in Scotland. Since that time Ulster Scots has been spoken in rural parts of Counties Antrim, Donegal, Down, and Londonderry/Derry, where it was mapped by Robert Gregg in the 1960s mainly on the basis of phonological features. The present article, based on eight years of fieldwork with native speakers in Antrim, analyzes a range of pronominal, verbal, and syntactic features, seeking to identify general patterns as well as variation within Ulster Scots. When possible, comparisons are made to Lowland Scots and Irish English in order to situate structural features of Ulster Scots within the larger linguistic landscape of the British Isles.
An inducible eukaryotic host-vector expression system: amplification of genes under the control of the polyoma late promoter in a cell line producing a thermolabile large T antigen.

Abstract We have taken advantage of the inherent instability of integrated polyoma (Py) DNA sequences in the presence of a functional viral large T antigen (LT) to develop a eukaryotic host-vector system where copy number is controlled by temperature. A mouse cell line WOP32-4, that constitutively expresses a temperature sensitive (ts) LT, was transfected with plasmids containing the Py origin of DNA replication (ori) and either a neomycin-resistance gene (neo) or chloramphenicol acetyl transferase gene (cat) linked to the Py late promoter. Stable transformants were selected at 39°C, the non-permissive temperature for the ts LT function. Upon shift to 33 °C, the resident Py sequences present in the WOP32-4 cells cannot excise due to an ori deletion. However, excision of the transfected plasmid molecules and subsequent extrachromosomal replication occur at high rates leading in some cases to the production of 1000–2000 copies per cell (average) of the plasmid. Proportional increases in either neo-specific mRNA or CAT activity were also observed. In situ hybridization for one cell line indicated that about 20% of temperature-shifted cells contained amplified plasmid DNA.
Monte Carlo simulation of membrane noise: An analysis of fluctuations in graded excitation of nerve membrane

Abstract Simple Monte Carlo methods are used to simulate intrinsic thermal and conductance noise in the Hodgkin-Huxley equations on a CDC 6400 digital computer. The goal of the analysis is to provide an explanation for the fluctuations in graded responses at T = 35 °C observed in squid giant axon by Cole, Guttman & Bezanilla (1970) . The thermal noise simulation did not provide satisfactory results. A fair agreement with the data was provided by the conductance noise simulations. This result is consistent with the observation that conductance noise amplitude observed in steady state squid axon preparations is substantially greater than the thermal noise amplitude at low frequencies.
Head-circumference distribution in a large primary care network differs from CDC and WHO curves.

OBJECTIVE: To compare currently available head-circumference growth curves to curves constructed from clinical measurements from patients in a large US primary care network (PCN). PATIENTS AND METHODS: We performed a retrospective cohort study of 75 412 patients in an urban-suburban PCN. Patients with a birth weight of RESULTS: The PCN curves were most similar to the National Center for Health Statistics (NCHS) curves and were substantially different from the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) curves. The overall proportion of observations above the 95th percentile was 4.9% (PCN), 6.2% (NCHS), 8.6% (CDC), and 14.0% (WHO). The proportion below the 5th percentile was 4.4% (PCN), 5.1% (NCHS), 2.9% (CDC), and 2.3% (WHO). When using the CDC curves, the proportion above the 95th percentile increased from 0.2% for children younger than 2 weeks to 11.8% for children 12 months old. When using the WHO curves, the proportion above the 95th percentile was >5% at all ages, with a maximum of 18.0% for children older than 24 months. CONCLUSIONS: The CDC and WHO head-circumference curves describe different distributions than the clinical measurements in our PCN population, especially for children with larger heads. The resulting percentile misclassification may delay diagnosis in children with intracranial pathology in very young infants and spur unnecessary evaluation of healthy children older than 6 months.
Undergraduate research experiences: Impacts and opportunities

Most undergraduates give high ratings to research experiences. Studies report that these experiences improve participation and persistence, often by strengthening students' views of themselves as scientists. Yet, the evidence for these claims is weak. More than half the 60 studies reviewed rely on self-report surveys or interviews. Rather than introducing new images of science, research experiences may reinforce flawed images especially of research practices and conceptual understanding. The most convincing studies show benefits for mentoring and for communicating the nature of science, but the ideas that students learn are often isolated or fragmented rather than integrated and coherent. Rigorous research is needed to identify ways to design research experiences so that they promote integrated understanding. These studies need powerful and generalizable assessments that can document student progress, help distinguish effective and ineffective aspects of the experiences, and illustrate how students interpret the research experiences they encounter. To create research experiences that meet the needs of interested students and make effective use of scarce resources, we encourage systematic, iterative studies with multiple indicators of success.
Pharmacopeia of qollahuaya andeans

This research report contains a list of 89 medicinal plants employed by the Qollahuaya (Callawaya) Andeans of Bolivia, who are famous herbalists in South America. This list contains botanical classification, origin of plant, quality, therapeutical properties, and medicinal uses. An analysis is made of the distribution of qualities and therapeutical uses to ascertain the scope of their pharmacology and incidence of disease. Therapeutic properties are interrelated with physiology in an effort to understand Qollahuaya ethnophysiology.
INTERACTIVE COMPUTER SOFTWARE: THE EFFECTS ON YOUNG CHILDREN'S READING ACHIEVEMENT

Abstract The intention of this study was to investigate the effects on reading comprehension when reading shorter and easier narrative text and longer and more difficult narrative texts on the printed page as compared to reading the same narrative texts using interactive CD‐ROM software displayed by the computer. Specifically, the ability of two classes of above‐average fourth‐grade children to answer comprehension questions about seven narrative stories was compared. One class of fourth‐grade children read each narrative from the actual book and answered six multiple‐choice questions about the story, while the second class of fourth‐grade children read the same narratives from interactive CD‐ROM software displayed on the computer and answered six multiple‐choice questions about the story. A three‐way analysis of variance on comprehension scores revealed that reading from computers increased comprehension scores when subjects were reading longer and more difficult narratives. Results indicated no differen...
Toxicity of Methyl- and Halogen-Substituted Alcohols in Tissue Culture Relative to Structure–Activity Models and Acute Toxicity in Mice

The relationship of in vitro and in vivo toxicity of a series of methyl- and halogen-substituted alcohols was examined with respect to their octanol-water partition coefficients (P), charge (Q), and steric (Es) parameters. A high correlation (r = 0.98) was found between tissue culture toxicity (ID50, the concentration required to produce 50% inhibition of growth) and hemolytic activity (H50, the concentration required to produce 50% hemolysis in saline, 37°). The product of intrinsic toxicity (Ti, the slope of the dose-response curve in tissue culture) and 1/P for aliphatic alcohols was found to have a uniform relationship to acute in vivo toxicity (LD50, the single intraperitoneal dose required to kill 50% of the mice in 7 days). The Ti/P to LD50 ratio showed a fourfold variation as compared to a 164-fold variation for the Ti/LD50 ratio. This relationship supported the conclusions that Ti from tissue culture was a valid, time-independent estimate of the toxicant-receptor interaction and that 1/P was directly related to the effective aqueous concentration of the toxicants in vivo. The Ti/P to LD50 ratio was higher for the halogenated than for the aliphatic alcohols, which suggested a difference in mechanism of the toxicant-receptor interaction. Hansch analysis showed both Q and Es parameters to be important to the differential intrinsic toxicities of the two groups. Both Free-Wilson and Hansch-Fujita analyses supported the conclusion that the tissue culture system conforms closely to the Higuchi-Davis equilibrium model. The usefulness of the tissue culture assay in conjunction with P for the analysis and prediction of in vivo toxicity was demonstrated.
Comparison of force and power generation patterns and their predictions under different external dynamic environments

Use of neural activity to predict kinematic variables such as position, velocity and direction etc of movements has been implemented in real-time control of robotic systems and computer cursors. In everyday life, however, we generate variable amounts of force to manipulate objects of different inertial properties or to follow the same trajectory under different external dynamic environments like air or water. The resultant work during such movements, and its time derivative power, should depend on the dynamics of the movement. In order to give the users of a brain-machine interface (BMI) comprehensive control of a prosthetic limb under different dynamic conditions, it is imperative to consider the dynamics-related parameters like end-effector forces, joint torques or power. In this paper, we show distribution patterns of two such dynamics parameters - force and power - and their predictive efficiency under different dynamic environmental conditions. We intend to find the force-related parameter, which has optimal predictive efficiency across different dynamic environments that is generalization. Our ultimate goal is to materialize a force-based brain-machine interface (fBMI).
A new application for time-delay reconstruction: detection of fast-phase eye movements

Abstract Time-delay embedding reconstructs a system's state space, using delayed values of a single variable. A novel application of this method is presented: identification of fast phases in eye-movement recordings. In the reconstructed space, a hyper-plane is fit to the slow phases; fast phases deviate from the plane. The method is demonstrated on sample data.
Open Access Within Reach: An Agenda for Action

ABSTRACT This is a critical time for open access. Researchers and higher education leaders need to take advantage of the substantial success of the past 2 years to support open access mandates by funders and institutions, and to support publishers in moving from subscription charging to article-processing charging. We need funders to commit to the explicit funding of publication costs, and universities to establish funds to support research that falls outside of grant-funding. Open access is at a watershed—it is time to move off the sidelines and create a new norm for scholarly communication.
Source of seed fluctuations for electromagnetic ion cyclotron waves in Earth’s magnetosphere

Abstract We consider a nonlinear wave energy cascade from the low frequency range into the higher frequency domain of electromagnetic ion cyclotron (EMIC) wave generation as a possible source of seed fluctuations for EMIC wave growth due to the ion cyclotron instability in Earth’s magnetosphere. The presented theoretical analysis shows that energy cascade from the Pc 4–5 frequency range (2–22 mHz) into the range of Pc 1–2 pulsations (0.1–5 Hz), i.e. into the frequency range of EMIC waves, is able to supply the needed level of seed fluctuations that guarantees growth of EMIC waves up to the observable level during one pass through the near equatorial region where the ion cyclotron instability takes place. We also analyze the magnetic field data from the Polar and Van Allen Probes spacecraft to test the suggested nonlinear mechanism. In this initial study we restrict our analysis to magnetic fluctuation spectra only. We do not analyze the third-order structure function, but judge whether a nonlinear energy cascade is present or whether it is not by only analyzing the appearance of power-law distributions in the low-frequency part of the magnetic field spectra. While the power-law spectrum alone does not guarantee that a nonlinear cascade is present, the power-law distribution is a strong indication of the possible development of a nonlinear cascade. Our analysis shows that a nonlinear energy cascade is indeed observed in both the outer and inner magnetosphere data, and EMIC waves are growing from this nonthermal background. All the analyzed data are in good agreement with the theoretical model presented in this study. Overall, the results of this study support a nonlinear energy cascade in Earth’s magnetosphere as a mechanism which is responsible for supplying seed fluctuating energy in the higher frequency domain where EMIC waves grow due to the ion cyclotron instability.
A knowledge based component/service repository to enhance analysts' domain knowledge for requirements analysis

Knowledge of the business domain (e.g., insurance claim, human resources) is crucial to analysts' ability to conduct good requirements analysis (RA). However, current practices afford little assistance to analysts in acquiring domain knowledge. We argue that traditional reuse repositories could be augmented by adding rich faceted information on component/services and artifacts such as business-process templates to help analysts acquire domain knowledge during RA. In this paper, we present the design of a Knowledge Based Component Repository (KBCR) for facilitating RA. Then, we report on the design and development of a KBCR prototype. We illustrate its application in a system that is populated with components and process templates for the auto insurance claim domain. An empirical study was conducted to assess its effectiveness in improving RA. Results showed that KBCR enhanced analysts' business domain knowledge and helped them better prepare for RA. Our key research contribution is to offer analysts a rich repository (i.e., KBCR) containing domain knowledge that they could utilize to acquire domain knowledge that is crucial for carrying out RA. While repositories of reusable components have been employed for some time, no one has used such repositories to help analysts acquire domain knowledge in order improve the RA of the system.
Diurnal rhythms in airway obstruction.

Abstract Diurnal patterns of variation in peak expiratory flow rate were studied in patients with all types of airway obstruction. Most regular patterns fall into one of two types: morning dip (M) with the lowest reading in the morning and (P) or double dip with the lowest readings morning and evening. Regular patterns were most frequently seen in asthmatics, but occurred also in bronchitis, particularly those with a history of wheeze. Treatment with bronchodilators reduces the prevalence of all regular patterns but does not abolish them. M pattern is characteristic of asthma but P pattern is the most frequent regular pattern seen in bronchitis. Amplitude of variation is greater in asthmatics than in simple bronchitics. It is reduced by about 20% with bronchodilators. Random observation of magnitude of response of peak flow rate to a bronchodilator is not a good indicator of amplitude of variation over the day. Because of the occurrence of a peak pattern in many patients the magnitude of diurnal variation may be underestimated by twice-daily peak flow rate readings. Treatment with corticosteroids does not appear strongly to influence either characteristic patterns or amplitude of variation.
Coal Conversion Technologies: Some Health and Environmental Effects

Several technologies to convert coal to liquid and gaseous fuels are being developed in the United States, some with support from the Department of Energy. Substitution of these technologies for those currently being used will produce different health and environmental hazards. In this article, selected health and environmental effects of four coal conversion and four existing technologies are compared. For each technology, the emission estimates for complete fuel cycles, including all steps in fuel use from extraction to the end use of space and water heating by electricity or direct combustion, were prepared by means of the Brookhaven Energy System Network Simulator model. Quantitative occupational health and safety estimates are presented for the extraction, transportation, distribution, processing, and conversion activities associated with each technology; also included are some public health damage estimates arising from fuel transportation and air pollution impacts. Qualitative estimates of health damage due to polycyclic organic matter and reduced sulfur are discussed. In general, energy inefficiencies, environmental residuals, and hence implied environmental effects and health damage increase in the order: (i) direct combustion of natural gas and oil, (ii) direct combustion of synthetic gas and oil, (iii) central-station electric power produced from synthetic gas, (iv) central-station electric power produced from coal, and (v) central-station electric power produced by the combustion of synthetic liquid fuels. The compliance and conflict of these technologies with the amendments of the Clean Air Act and other legislation are discussed.