cssi/SciSciGPT-SciSciNet huggingface dataset:
Metabolic and Endocrine Changes at Altitude

a unique opportunity to study the effects of prolonged exposures to altitudes above 5,000 m was provided by the 1981 American Medical Research Expedition to Everest (AMREE). A detailed assessment of the fasting metabolic state, in which the levels of key metabolites and hormones were measured, was included in the program. Fourteen adult male subjects between the ages of 28 and 52 yr (mean = 36) were studied at sea level and again during exposures to altitudes of 5,400 m and 6,300 m. This chapter details the similarities and differences between previous studies at moderate altitudes and the AMREE findings at more extreme altitudes.
Comment on “Hot, dry, wet, cold or toxic? Revisiting the ecological significance of leaf cuticular micromorphology” by M. Haworth and J.C. McElwain [Palaeogeography, Palaeoclimatology, Palaeoecology 262 (2008) 79-90]

Haworth and McElwain (2008) reach the illogical conclusion that xeromorphic features of plants are not xeromorphic because of confusion between genetic and descriptive terminology. Descriptive terms for the suite of plant features including thick cuticles are scleromorph, sclerophyte, or sclerophyll (Greek σκληρον meaning “hard, harsh, rough, stiff”), not xeromorph, and descriptive redefinition of “xeromorph” by Haworth and McElwain (2008, inter alia) is confusing. Xeromorph is a form attributed to dry climate, and is thus unavoidably genetic: xeromorphic implies that scleromorphic features were induced by dry climate. Scleromorphy can also be produced by other environmental hardships, such as nutrient shortage (peinomorphy of Walter, 1973) and high salinity (halophyty, e.g. Rich et al., 2008: “halomorphic” is generally used for soils rather than plants, e.g. Mendoza et al., 2005). Haworth and McElwain's (2008) failure to mention halophytes is puzzling, because there are several published interpretations of their chosen example, Pseudofrenelopis parceramosa, as a mangrove or salt marsh plant (Retallack and Dilcher, 1986). Halophyty is a common explanation for the hard leaves and succulence of mangroves and glassworts (Walter, 1973). Peinomorphy is a commonexplanation for small stiff leaves of coastal heaths or pygmy forest in silica–iron soils (Spodosols) or on mineral-poor peats (Histosols: Walter, 1973; Jenny, 1980; Retallack, 1997). Peinomorphy may also be created by the acidic leaching environments of elevated atmospheric CO2 and in areas of SO2 gases from volcanic fumaroles, because both gases have the effect of acidifying substrates to make nutrient acquisition difficult (Retallack, 2001). A final possibility not mentioned by Haworth andMcElwain (2008) is that scleromorphymay have no environmental significance in itself. Krausel (1923) argued from
Ultrasonic characterization of mechanical properties of Cr- and W-doped diamond-like carbon hard coatings

Two ultrasonic nondestructive evaluation methods have been applied to systematically characterize the mechanical properties of nano-structured physical vapor deposited diamond-like carbon (DLC) ultra-hard coatings. A photoacoustic guided-wave technique is used to generate broadband surface acoustic waves (SAW) on the coating surfaces, and dispersion relations of the SAW for DLC coatings are measured with frequencies up to about 150 MHz. In addition, line-focus acoustic microscopy is used to investigate the dispersion curves of leaky SAW on coatings in the ultrasonic frequency range from 140 MHz to 240 MHz. A multi-layer material model is used to analyze the wave propagation phenomena in the DLC coating specimens and the transfer matrix method is used to numerically calculate theoretical dispersion curves. The measured acoustic dispersion curves by the two ultrasonic methods are therefore independently analyzed by a nonlinear optimization approach in the inverse problem. The derived Young's moduli using the two ultrasonic techniques are compared with nano-indentation tests and good quantitative agreement is found. An example application of photoacoustic methods to a curved gear component is also shown.
NMR Studies of Chiral P,S-Chelate Platinum, Rhodium, and Iridium Complexes and the X-ray Structure of a Palladium(II) Allyl Derivative

Several Rh(I), Ir(III), and Pt(II) complexes of the chiral P,S-bidentate ligand 2 have been prepared and characterized. Detailed two-dimensional NMR studies show that (i) the boat-type chelate ring and the stereogenic sulfur center can invert rapidly at ambient temperature and (ii) the sulfur donor may dissociate, essentially destroying the chiral pocket. The solid-state structure of [Pt(η3-C3H5)(2)]PF6 (3) has been determined and the sulfur substituent shown to have an axial orientation. The six-membered chelate ring takes up a boatlike conformation. As shown by an X-ray diffraction study for 3, and via incoherent inelastic neutron scattering (IINS) measurements for the Pd analog, 4, the OH group is remote from the metal atom.
Pervasive wetland flooding in the glacial drift prairie of North Dakota (USA)

This article describes a unique flood hazard, produced by the dramatic expansion of wetlands in Nelson County, located within the North American Prairie Pothole Region of North Dakota, USA. There has been an unprecedented increase in the number, average size, and permanence of prairie wetlands, and a significant increase in the size of a closed lake (Stump Lake) due to a decade-long wet spell that began in 1993 following a prolonged drying trend. Base-line land cover information from the 1992 USGS National Land Cover Characterization dataset, and a Landsat TM scene acquired 9 July 2001 are used to assess the growth of the closed lake and wetland pond surface areas, and to analyze the type and area of various land cover classes inundated between 1992 and 2001. The open water profile in Nelson County changed from one marked by relatively comparable coverage of closed lake and wetland pond areas in 1992, to one in which wetland open water accounted for the vast majority of total open water in 2001. The bulk of the wetland pond area expansion occurred by displacing existing wetland vegetation and agricultural cropland. Producers responded to the flood hazard by filing Federal Crop Insurance Corporation (FCIC) claims and enrolling cropland in the Conservation Reserve Program (CRP), a federal land retirement program. Land taken out of agricultural production has had an enormous impact upon the agricultural sector that forms the economic base of the rural economy. In 2001 the land taken out of production due to CRP enrollment and preventive planting claims represented nearly 42% of Nelson County’s 205.2 K ha base agricultural land. The patterns obtained from this detailed study of Nelson County are likely to be the representative of the more publicized flood disaster occurring within the Devils Lake Basin of North Dakota.
Economics of whisker-reinforced ceramics

Abstract Research on ceramic composites has largely neglected the economics of production. To examine this issue, a series of computerized cost models were created which simulate the production of SiC whiskers and their incorporation into ceramic composites. Analysis indicates that the cost of current production technologies will limit whisker-reinforced ceramics to speciality applications. Cost drivers are capital-intensive hot pressing and labour-intensive machining.
Application of micromechanical polycrystalline model in the study of threshold stress effects on superplasticity

Abstract The mechanical behavior of superplastic materials is characterized by a sigmoidal curve (regions I, II and III) spanning about seven to eight decades of strain rate in log σ− log e plot. Most of the superplastic deformation models cover only the superplastic regime (region II), over a small range of strain rate. We have previously proposed a model based on micromechanics to predict the mechanical behavior of material in regions II. In this work the model is modified to cover all the three regions and to predict the presence or absence of superplasticity in a given material. The new model incorporates a threshold stress term for diffusional flow at the atomic level which manifests as the experimentally observed threshold stress at the macro level. The model is applied to superplastic materials including statically recrystallized 7475 aluminum alloy, dynamically recrystallizing 2090-OE16 aluminum–lithium alloy and an Al–Zn–Mg–Cu alloy. With the introduction of the threshold stress, the influence of grain size and temperature on the behavior of these materials can be predicted over a wider range of strain rate. Also the maximum strain-rate sensitivity and its corresponding strain rate can be fairly accurately predicted. The variation of threshold stress with respect to grain size and temperature is also studied and an activation energy term is suggested for describing the threshold phenomenon.
Upper airway segmentation and dimensions estimation from cone-beam CT image datasets

Objective To segment and measure the upper airway using cone-beam computed tomography (CBCT). This information may be useful as an imaging biomarker in the diagnostic assessment of patients with obstructive sleep apnea and in the planning of any necessary therapy. Methods With Institutional Review Board Approval, anonymous CBCT datasets from subjects who had been imaged for a variety of conditions unrelated to the airway were evaluated. DICOM images were available. A segmentation algorithm was developed to separate the bounded upper airway and measurements were performed manually to determine the smallest cross-sectional area and the anteriorposterior distance of the retropalatal space (RP-SCA and RP-AP, respectively) and retroglossal space (RG-SCA and RG-AP, respectively). A segmentation algorithm was developed to separate the bounded upper airway and it was applied to determine RP-AP, RG-AP, the smallest transaxial-sectional area (TSCA) and largest sagittal view airway area (LCSA). A second algorithm was created to evaluate the airway volume within this bounded upper airway. Results Measurements of the airway segmented automatically by the developed algorithm agreed with those obtained using manual segmentation. The corresponding volumes showed only very small differences considered clinically insignificant. Conclusion Automatic segmentation of the airway imaged using CBCT is feasible and this method can be used to evaluate airway cross-section and volume comparable to measurements extracted using manual segmentation.
The role(s) of gangliosides in neural differentiation and repair: a perspective.

Abstract Gangliosides, sialylated glycosphingolipids, are found in greatest concentration in the brain. While they were first characterized as a unique class of lipids almost 50 years ago, little is known regarding their actual function. It is known that (a) ganglioside composition changes during development, (b) different types of neural cells have specific gangliosides associated with them, (c) the accumulation of gangliosides in certain inborn errors of metabolism results in the formation of aberrant meganeurites, and (d) gangliosides appear to enhance recovery from certain neural traumas. Recent work suggests that it is the oligosaccharide portion of the ganglioside that carries much of the biological specificity. Coupled with observations that ganglioside-binding proteins are present on the plasma membranes of cells, it suggests the hypothesis that gangliosides present on the surface of one cell may interact with specific ganglioside-binding proteins, “receptors,” on target cells. As a result of the ganglioside-binding protein interaction, a signal could be transmitted to the cell. This might occur via modulation of the effect of the endogenous ganglioside on the activity of a kinase(s) or by an alteration in ionic flux. The signal would initiate the appropriate cellular response.
Enhancement of the blood pressure activity of VAL5-and ILE5-angiotensin II by sodium and calcium ions.

Nachweis, dass die Blutdruckaktivitat von Val5-, Ile5- und Asn1,Val5-Angiotensin II durch NaCl gesteigert wird. Die Aktivitat der naturlichen Hormone wird jedoch von CaCl2 nicht signifikant erhoht, obwohl das Ion die Aktivitat von Asn1,Val5-Angiotensin II stark vermehrt.
Characterization of alpha-actinin from Acanthamoeba

Characterization of a protein from Acanthamoeba that was originally called gelation protein [T.D. Pollard, J. Biol. Chem. 256:7666-7670, 1981] has shown that it resembles the actin filament cross-linking protein, alpha-actinin, found in other cells. It comprises about 1.5% of the total amoeba protein and can be purified by chromatography with a yield of 13%. The native protein has a molecular weight of 180,000 and consists of two polypeptides of 90,000 Da. The Stokes' radius is 8.5 nm, the intrinsic viscosity is 0.35 dl/dm, and the extinction coefficient at 280 mm is 1.8 X 10(5)M-1 X cm-1. Electron micrographs of shadowed specimens show that the molecule is a rod 48 nm long and 7 nm wide with globular domains at both ends and in the middle of the shaft. On gel electrophoresis in sodium dodecylsulfate the pure protein can run as bands with apparent molecular weights of 60,000, 90,000, 95,000, or 134,000 depending on the method of sample preparation. Rabbit antibodies to electrophoretically purified Acanthamoeba alpha-actinin polypeptides react with all of these electrophoretic variants in samples of purified protein and cell extracts. By indirect fluorescent antibody staining of fixed amoebas, alpha-actinin is distributed throughout the cytoplasmic matrix and concentrated in the hyaline cytoplasm of the cortex. The protein cross-links actin filaments in the presence and absence of Ca++. It inhibits slightly the time course of the spontaneous polymerization of actin monomers but has no effect on the critical concentration for actin polymerization even though it increases the apparent rate of elongation to a small extent. Like some other cross-linking proteins, amoeba alpha-actinin inhibits the actin-activated ATPase of muscle myosin subfragment-1. Although Acanthamoeba alpha-actinin resembles the alpha-actinin from other cells in shape and ability to cross-link actin filaments, antibodies to amoeba and smooth muscle alpha-actinins do not cross react and there are substantial differences in the amino acid compositions and molecular dimensions.
The Effects of Vocalics and Nonverbal Sensitivity on Compliance A Speech Accommodation Theory Explanation

A speech accommodation theory explanation for the interaction between a receiver's decoding ability and a speaker's voice tone on compliance with requests for help was tested. It was predicted that good decoders would speak faster than poor decoders. Speech accommodation theory predicts that given this speech style difference, good decoders would make more favorable interpretations of a fast request that converged toward their faster speech rate; whereas poor decoders would make more favorable interpretations of a slow request that converged toward their slower speech rate. Requests receiving more favorable evaluations should result in greater compliance, because compliance with requests for help was predicted to follow an identification process. An experiment involving 168 participants confirmed this explanation. Good decoders spoke faster than poor decoders. Moreover, good decoders rated the fast request as more intimate and immediate, while poor decoders rated the slow request as more intimate and immediate. Good decoders, in turn, complied more with the fast request, which they rated more intimate and immediate, whereas poor decoders complied more with the slow request, which they rated more intimate and immediate.
The generation gap and optimal economic growth

Abstract Among the problems confronting those who aspire to the development of a realistic and practicable optimal growth theory is that the human population is not homogeneous with respect to age. Those who are relatively young are apt to prefer a different pattern of capital accumulation from that preferred by those who are relatively old. This paper proposes a tentative solution to this particular problem. Essentially the proposal is that society should remain with what is an optimal private plan of an individual who is at the median age of the population at the beginning of the planning period, for one planning period, after which it revises the plan to switch to the optimal private plan of another individual (one planning period younger than the first) who is at the median age at the commencement of the new planning period. Thus the optimal social plan consists of a succession of one planning period implementations of the first periods of the optimal private plans of individuals who are at the median age at that time period. An example of the application of the method is given. An important sidelight of the paper is a critique of standard constant-rate exponential discounting in social planning of optimal capital accumulation, and the proposal that it be replaced by “mortality discounting.”
Integration by design

As goes history, so goes research: this year, activity in areas of retrovirus research related only indirectly have provoked events that are notable when considered together. Last summer it was reported that a patient in one X-linked severe combined immunodeficiency retroviral vector gene therapy trial had developed leukemia. Now disquietingly, there has been a second such event, and a third patient is reported to have a vector insertion near the same gene (LMO2) as observed in the other two individuals (1). Meanwhile, in a basic research laboratory, experiments have moved us another step closer to understanding the mechanics of insertion specificity for retrovirus-type integrases (IN). As reported in this issue of PNAS, investigators have produced active retroviruslike elements with synthetic insertion specificities (2). Dan Voytas and colleagues at Iowa State University (Ames) study the Saccharomyces long terminal repeat (LTR)-retrotransposon Ty5, which targets heterochromatic regions (3). Now, in an elegant adaptation of the two-hybrid system, the 6-aa Ty5 targeting domain (TD) was exchanged for two heterologous domains shown to mediate interaction of their respective proteins with protein partners. When domains from those partners were produced fused to the LexA DNA-binding domain, targeting to LexA-binding sites was observed. Although integration specificity in the system was by no means absolute, these results are of interest to genetic engineers and future gene therapists.
Discrete heterogeneous quaternary structure formed by α/β-peptide foldamers and α-peptides

The development of unnatural oligomers that adopt predictable secondary structures has led to increased interest in expanding the conformational repertoire of foldamers to include discrete, cooperatively folded tertiary and quaternary structures. Here we report the first examples of heterogeneous quaternary structure: stable tetrameric helix bundles incorporating both α-peptides and α/β-peptide foldamers. The results suggest that hydrophobic interactions in the core of the helix bundle contribute to the stability of the assembly, as do cyclic β-amino acid residues within the α/β-peptide. These observations demonstrate that secondary structural elements in well-folded tertiary or quaternary structures need not have the same backbone composition. Our findings highlight the prospect that diverse combinations of foldamer and α-peptide subunits could lead to folding and/or assembly behavior reminiscent of that necessary for complex protein function.
Long-term predictors of subsequent cardiovascular events with coronary artery disease and 'desirable' levels of plasma total cholesterol.

BACKGROUNDPatients with coronary artery disease (CAD) are at considerable risk for subsequent cardiovascular events. Although hyperlipidemia accentuates the risk, predictors of subsequent events with CAD and desirable total cholesterol (TC) (less than 5.2 mmol/l) have not been assessed.METHODS AND RESULTSA survival analysis was performed in a subset of 740 consecutive patients who underwent diagnostic coronary arteriography between 1977 and 1978. Eight-three men and 24 women with angiographically documented CAD and desirable TC were followed for subsequent cardiovascular events, including myocardial infarction and cardiovascular death. Over a 13-year period, 75% of CAD subjects with reduced high density lipoprotein cholesterol (HDL-C) (less than 0.9 mmol/l) developed a subsequent cardiovascular event compared with 45% of those with HDL-C greater than or equal to 0.9 mmol/l (p = 0.002). A Kaplan-Meier analysis revealed significantly greater survival from cardiovascular end points in patients with baseline ...
Physiology's Impact: Stop Ignoring the Obvious–SEX MATTERS!

We live in the world of individualized medicine, where knowledge of the human genome is helping to guide specific diagnosis and clinical treatment at the individual level. Yet, all too often, we ignore the basic distinction of sex in our experiments and the evidence base for clinical practice.
You can't always get what you want: The influence of unexpected task constraint on voluntary task switching

The current study assessed the effect that unexpected task constraint, following self-generated task choice, has on task switching performance. Participants performed a modified double-registration voluntary task switching procedure in which participants specified the task they wanted to perform, were presented with a cue that, on the majority of trials, confirmed the choice, and then performed the cued task. On a small portion of trials, participants were cued to perform a task that did not match their choice. Trials on which cues unexpectedly failed to match the chosen task were associated with costs. These costs were particularly large when participants chose to switch tasks but had to unexpectedly repeat the previous task. The results suggest that when participants choose to switch tasks, they prepare for that switch in anticipation of the stimulus, and the preparation is durable such that it cannot be readily undone.
Neurovascular entrapment due to combat-related heterotopic ossification in the lower extremity.

Background: Heterotopic ossification is the ectopic formation of mature lamellar bone in nonosseous tissue. The prevalence of heterotopic ossification following combat injuries is much higher than civilian data would suggest. In certain cases, the aberrant bone formation can envelop major neurovascular structures in the lower extremity, leading to symptomatic neurovascular entrapment. Methods: We describe five consecutive cases of heterotopic ossification leading to symptomatic neurovascular entrapment in the lower extremity as a result of blast trauma and present our method of patient assessment, preoperative planning, and surgical excision. Results: Heterotopic bone was successfully excised without neurovascular injury in all patients. At a mean of twenty months (range, eight to forty-five months) postoperatively, all patients demonstrated continued improvement of their pre-excision function. All patients who had neuropathic pain had a decrease in the pain. Those with decreased joint motion regained motion once their wounds were stable. Sensory deficits resolved before motor deficits did. There was no recurrence of clinically relevant heterotopic ossification in this series. Conclusions: Excision of heterotopic bone, particularly with concurrent neurovascular entrapment, can be associated with major short-term and long-term complications. With use of our treatment algorithm, involving careful preoperative planning and meticulous operative excision, heterotopic bone entrapping major neurovascular structures following severe extremity trauma can be safely excised with subsequent clinical improvement. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Luteinizing Hormone/Choriogonadotropin-Dependent, Cholera Toxin-Catalyzed Adenosine 5′-Diphosphate (ADP)-Ribosylation of the Long and Short Forms of Gsα and Pertussis Toxin-Catalyzed ADP-Ribosylation of Giα

Although it is well established that activated LH/human (h) CG receptor stimulates adenylyl cyclase activity (via the heterotrimeric stimulatory guanine nucleotide-binding protein, Gs) and in some cells stimulates phospholipase C activity, there is no evidence for a direct physical interaction between the LH/CG receptor and Gs or any other G protein(s). We conducted studies using cholera toxin (CTX) and pertussis toxin (PTX) to determine which Gα proteins were associated with the LH/CG receptor in ovarian follicular membranes. Since hormone-dependent, CTX-catalyzed ADP ribosylation (AR) constitutes evidence that a Gα protein is specifically associated with a receptor, CTX-catalyzed AR of membrane proteins was examined both in the presence and absence of guanine nucleotides to determine which G proteins exhibit hCG-dependent labeling by[ 32P]NAD. Results demonstrated the time- and hCG-dependent AR of both a 45-kDa protein and a 48/50-kDa doublet as well as a 40-kDa protein that was also sensitive to AR by ...
The Process of Political Development: An Illustrative Use of a Strategy for Regression in the Presence of Multicollinearity

Although a number of investigators have attempted to identify empirically a process of political development, substantial controversy still surrounds a determination of the causal factors involved. It is my contention that this state of affairs is the result of inadequacies inherent in traditional techniques of causal modeling, and aggravated when multicollinear variables are involved. To resolve this problem I first review a technique capable of reducing the confounding effects of multicollinearity. I then illustrate use of this technique, as well as a strategy for inferring causal relationships, by means of a reanalysis of published data used to construct models of political development. The strategy for causal inference utilized herein is derived from knowledge of the effects of model specification errors. On the basis of these findings a new causal model of political development, which is both theoretically and empirically consistent, is presented.
Electric fields and conductivity in the nighttime E-region: A new magnetosphere-ionosphere-atmosphere coupling effect

Calculations have been made of the effects of intense poleward-directed electric fields upon the nighttime ionospheric E-region. The results show the Pedersen and Hall conductivities are substantially changed, thereby decreasing the ionospheric electrical load seen by magnetospheric sources. It appears that relatively large electric fields can exist in the absence of accompanying large field-aligned currents, as long as the underlying ionosphere remains in darkness and/or energetic particle precipitation is absent.
Influence of chroma and hue on spatial balance of color Pairs

Earlier research has shown that the relative chroma (saturation) of color pairs affects the relative areas of those colors that appear balanced in a predictable way. Small areas of high chroma balance large areas of low chroma. The present study shows that this chroma effect is independent of the background the colors were viewed against, and relatively independent of the hues involved. In particular, the chroma effect is as strong for hue pairs adjacent or intermediate on the color circle as for complementary hues. Finally, this study compared Munsell's theory of spatial balance to that of Moon and Spencer, finding better agreement with the former.
‘Giant’ CdSe/CdS Core/Shell Nanocrystal Quantum Dots As Efficient Electroluminescent Materials: Strong Influence of Shell Thickness on Light-Emitting Diode Performance

We use a simple device architecture based on a poly(3,4-ethylendioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-coated indium tin oxide anode and a LiF/Al cathode to assess the effects of shell thickness on the properties of light-emitting diodes (LEDs) comprising CdSe/CdS core/shell nanocrystal quantum dots (NQDs) as the emitting layer. Specifically, we are interested in determining whether LEDs based on thick-shell nanocrystals, so-called "giant" NQDs, afford enhanced performance compared to their counterparts incorporating thin-shell systems. We observe significant improvements in device performance as a function of increasing shell thickness. While the turn-on voltage remains approximately constant for all shell thicknesses (from 4 to 16 CdS monolayers), external quantum efficiency and maximum luminance are found to be about one order of magnitude higher for thicker shell nanocrystals (≥13 CdS monolayers) compared to thinner shell structures (<9 CdS monolayers). The thickest-shell nanocrystals (16 monolayers of CdS) afforded an external quantum efficiency and luminance of 0.17% and 2000 Cd/m(2), respectively, with a remarkably low turn-on voltage of ~3.0 V.
A computational introduction to STEM studies

We report on the content and early evaluation of a new introductory programming course “Media Propelled Computational Thinking,” (abbreviated MPCT and pronounced iMPaCT). MPCT is integrated into a freshman-level program designed for under-prepared students with interests in a STEM discipline. It is intended to reduce attrition rates by fostering student intuition in, appreciation of, and confidence about basic pre-calculus concepts. The MPCT curriculum is problem-driven, with analytical challenge exercises that are intended to motivate inquiry and to illustrate the reasoning used in the STEM professions Preliminary evaluation results are encouraging — students from a wide range of academic majors found MPCT engaging, and report that the course conveyed insight, and decreased anxiety about foundational mathematical concepts.
Second language learners' processes of L1 writing, L2 writing, and translation from L1 into L2

Abstract This study compares second language learners' L1 writing, L2 writing, and translation from L1 into L2, focusing on writing and translating processes, attention patterns, and quality of language use. Thinking aloud, 22 Japanese ESL students studying at a Canadian college performed 3 tasks individually. These think-aloud protocols were analyzed, supplemented by observational notes and interviews, and the writing samples were evaluated. The data were analyzed with attention to theories of composing processes (Bereiter & Scardamalia, 1987), Schmidt's “conscious attention” (1990), and Swain's “i + 1 output” hypothesis (1985). It was found that (a) most students used a “what-next” approach both in the L1 and L2 writing tasks and a “sentence-by-sentence” approach in the translation task, (b) attention patterns in the L1 and L2 writing tasks were very similar, but quite different in the translation task. Attention to language use in the translation task was significantly higher than in the L1 and L2 writing tasks and, (c) scores on language use in the L1 and L2 writing tasks were similar, but scores on language use in the translation task were significantly better than in the L2 writing task.
Lath-Shaped Units in Fine-Grained Micas and Smectites

Transmission electron images of fine-grained micas in bentonites exhibit lath-shaped units. These units seem to be associated along the (110) planes—referred to 2M1 mica cell—with perfect registry of their individual lattices. In doing so, they seem to provide lateral growth in the (001) plane. These lath-shaped units are arranged in the [001] direction in modes similar to the stacking of layers in mica polymorphs. Aggregations of lath-shaped units with polycrystalline montmorillonite particles are also observed in several bentonites. From the SAD pattern these laths are inferred to be dioctahedral layer silicates. However, they cannot be exactly identified any further. It is an open question whether these laths have grown from the montmorillonite or are simply entangled with it.
Near-Infrared Spectrophotometry and the CO Emission in V2274 Cygni (Nova Cygni 2001 No. 1)

Infrared spectroscopy of V2274 Cygni (=Nova Cygni 2001 No. 1) is presented for two widely separated epochs, 17 and 370 days after discovery. In addition to the Paschen and Brackett series of H I, the early-time spectrum shows strong emission lines of C I and N I, fluorescently excited lines of O I, and emission from the first overtone of carbon monoxide. Because the initial data were probably acquired no more than 18 days after outburst, CO molecule formation occurred remarkably quickly in the dense, cool, carbon and oxygen rich ejecta. Rapid formation was also seen in NQ Vul, V842 Cen, and V705 Cas, three other novae in which first-overtone CO emission has been detected. Formation of the CO molecule may occur chemically in a process that requires H2 as a precursor or directly through radiative association. The overtone emission of V2274 Cyg indicates a temperature of ~2500 K. The vibrational levels show no obvious departures from thermal equilibrium, which may indicate high optical depths in the fundamental. A large 13C/12C ratio (0.83 ± 0.3) is also indicated by the observations, consistent with the fast CNO burning expected in novae explosions. By the time of the second epoch observations, the emission lines of the neutral C, N, and O had disappeared. He I λ10830 was the dominant emission feature in the spectrum. In addition to the hydrogen lines, recombination features of He II were also strong. The common nebular lines of [S III] were seen but only two coronal line, [S VIII] λ9911 and [Si VI] λ19645, were detected. The CO emission had disappeared, but a strong thermal dust component was present. The interstellar reddening for the system was found to be E(B-V) = 1.3. This extinction, together with the absolute magnitude derived from the rate of decline of the light curve, suggest a distance of ~10.8 kpc. This places V2274 Cyg well out of the Galactic plane. The small number of novae with spectroscopic detections of carbon monoxide all have prominent C I lines, moderate speed classes and ejection velocities, exhibit marked dust formation events, and result from an explosion on a CO-type white dwarf. Based on these similarities, the spectrum of V2274 is proposed as a likely near-infrared spectral template for other novae that display carbon monoxide emission.
The effect of hetastarch (670/0.75) on urine specific gravity and osmolality in the dog.

Background: Urine specific gravity (USG) is used clinically to estimate urine osmolality (UOsm). Although USG has been shown to have a linear correlation with UOsm in dogs, the relationship is altered when there are significant numbers of high molecular weight (MW) molecules in the urine. Hypothesis: USG would no longer predict UOsm in dogs given intravenous hetastarch (670/0.75)(HES). Animals: Eight healthy employee-owned adult dogs. Methods: Prospective, controlled experimental study. USG and UOsm were measured every 30 minutes from t=0 minutes to t=360 minutes. Dogs were administered 20mL/kg of either NaCl 0.9% (control group, n=4) or HES (treatment group, n=8) IV over 1 hour starting at t=90 minutes. Results: There was a decrease in UOsm in both groups starting at t=120 minutes and continuing for the study duration, and there was no significant difference in UOsm between treatment and control groups across all time points. There was an appropriate decrease in USG from t=120 minutes for the control group. In the treatment group, USG increased significantly at t=120 minutes (P= .0006), t=150 minutes (P= .0002), and t=180 minutes (P= .0044). The largest increase in USG occurred at t=150 minutes with a mean USG of 1.070 ± 0.021 (range 1.038-1.104). Conclusions and clinical importance: Urine specific gravity should not be used to estimate urine solute concentration in dogs following the administration of 20mL/kg of HES. In a clinical setting, the evaluation of USG following this dose of HES may lead to an overestimation of urine concentration.
Finite Frequency Range Kramers-Kronig Relations: Bounds on the Dispersion

Dispersion inequalities are presented to check for the self-consistency of experimentally obtained complex moduli, such as the complex dielectric constant, magnetic permeability, and complex bulk and shear moduli of viscoelastic materials. Unlike the Kramers-Kronig dispersion relations, they only require measurements over a finite frequency range. They can provide highly accurate interpolation formulas for the real part, given its value at a few selected frequencies and given the imaginary part over a range of frequencies.
Mechanism of adhesion of alumina on MCrAlY alloys

X-ray diffraction has been used to measure stains/ stresses generated in oxide films formed under isothermal conditions at 1150–1225° C and cooled to room temperature. High compressive strains, of the order of 1%, were measured in alumina films formed on FeCrAlY. However, little or no strain was measured in oxide films on NiCrAlY and NiCoCrAlY samples, even when there was no scale spallation. Auger Electron Spectroscopy (AES) experiments have also been conducted to evaluate the role of segregation on scale adhesion. Our studies suggest that the adhesion mechanism might depend on the alloy composition. On iron-based alloys, the scale spallation might be prevented by mechanisms that involve strong bonding at the interface. On the other hand, the scale spallation on nickel-based alloys might be prevented by a mechanism that relieves stresses. Yttrium segregation might help in this process.
Reparameterization of RNA χ Torsion Parameters for the AMBER Force Field and Comparison to NMR Spectra for Cytidine and Uridine

A reparameterization of the torsional parameters for the glycosidic dihedral angle, χ, for the AMBER99 force field in RNA nucleosides is used to provide a modified force field, AMBER99χ. Molecular dynamics simulations of cytidine, uridine, adenosine, and guanosine in aqueous solution using the AMBER99 and AMBER99χ force fields are compared with NMR results. For each nucleoside and force field, 10 individual molecular dynamics simulations of 30 ns each were run. For cytidine with AMBER99χ force field, each molecular dynamics simulation time was extended to 120 ns for convergence purposes. Nuclear magnetic resonance (NMR) spectroscopy, including one-dimensional (1D) 1H, steady-state 1D 1H nuclear Overhauser effect (NOE), and transient 1D 1H NOE, was used to determine the sugar puckering and preferred base orientation with respect to the ribose of cytidine and uridine. The AMBER99 force field overestimates the population of syn conformations of the base orientation and of C2′-endo sugar puckering of the pyri...
The BBZ/Wor rat: clinical characteristics of the diabetic syndrome

The BBZ/Wor rat is a model of obesity and autoimmune diabetes mellitus developed by crossing the BB/Wor and Zucker rats. We studied circulating glucose and insulin levels, islet morphology and lymphocyte subsets in lean and obese BBZ/Wor rats before and after the onset of diabetes, and studied the clinical course of diabetes in animals after interruption of exogenous insulin therapy. Lean BBZ/Wor rats developed insulin-dependent diabetes and died in ketoacidosis within 1 week after cessation of insulin injections. Diabetes also developed in obese rats, but these animals were not insulin-dependent and survived for months without insulin therapy. The islets of the lean diabetic rats revealed complete destruction of pancreatic beta cells and plasma insulin levels were virtually undetectable. In contrast, the islets of the obese rats revealed insulitis and substantial beta-cell loss, however autoimmune bete-cell destruction was incomplete, and residual beta cells were presumably responsible for the presence of measurable levels of plasma insulin and the long-term survival of obese diabetics without insulin therapy. Obese rats were hyperinsulinaemic, developed diabetes significantly earlier, and with a greater incidence than lean rats, suggesting a possible relationship between enhanced beta-cell metabolic activity and immune destruction. Obese males became diabetic more frequently and at an earlier age than obese females and lean rats of both sexes, suggesting a role for gender in the pathogenesis of diabetes. We conclude that the BBZ/Wor rat is a unique animal model for investigating the interaction of obesity, beta-cell metabolism, autoimmune insulitis and genetic predisposition to diabetes.
Semiconducting Polymers for Thin‐Film Electronics

An overview of practical issues related to the adoption of semiconducting polymers in thin‐film electronic devices is presented. Performance requirements for organic light emitting diodes, thin‐film transistors and photovoltaic devices are reviewed.
Development of the fetal intestine in mice lacking the glucocorticoid receptor (GR).

During rodent development there are two surges of circulating corticosterone: one just prior to birth and then one in the third postnatal week. Prior studies have shown that the latter controls the rate of intestinal development in the postnatal period. To date, a role for the earlier surge in the prenatal phase of intestinal development has not been investigated. We hypothesized that the late fetal surge of circulating corticosterone is involved in both morphologic and functional maturation of the intestinal epithelium, and thus that such maturation would be delayed if glucocorticoid action was abrogated. The hypothesis was tested by studying intestinal development in mice lacking a functional glucocorticoid receptor (GR). After GR+/- mice were bred onto a C57Bl/6 background, heterozygote matings yielded the expected ratios of -/-, +/-, and +/+ offspring. Analysis of GR mRNA in intestines of +/+ and -/- fetuses confirmed expression in wild-type mice but not in the GR-null mice. Intestinal histology of GR+/+ and -/- littermates at E13.5, E15.5, and E18.5 showed no effect of GR genotype on morphologic development. Further studies at E18.5 showed that GR-/- mice have normal functional maturation of the intestinal epithelium as assessed by: lactase activity in the enterocyte lineage, normal numbers of goblet and enteroendocrine cells, and normal numbers of proliferating cells in the intestinal crypts. Neither the minerolocorticoid receptor (MR) nor the pregnane X receptor (PXR) showed compensatory up-regulation in GR-/- mice. We conclude that, in contrast to our original hypothesis, the rodent intestine passes through a phase of glucocorticoid independence (late fetal) prior to becoming responsive to glucocorticoids in the postnatal period. These findings have implications for the clinical use of corticosteroids to enhance intestinal maturation in preterm infants.
Successful treatment of inflammatory linear verrucous epidermal nevus with tacrolimus and fluocinonide.

Background Inflammatory linear verrucous epidermal nevus (ILVEN) is a relatively rare disorder that is characterized by an early age at onset; severely pruritic linear papules and plaques; histologic features resembling spongiotic dermatitis, psoriasis, or lichenified dermatitis; and poor response to treatment. Objective To report the successful treatment of ILVEN with potent topical steroid and tacrolimus ointments. Methods An 11-year-old girl presented with a 1-year history of markedly pruritic, progressive linear eruption that extended from the right foot to the right buttock. She had failed treatment with pimecrolimus, calcipotriol, mometasone furoate, triamcinolone, tazarotene, and alpha-hydroxy acid. Histologic examination revealed the findings of spongiotic dermatitis. Results The lesions resolved with fluocinonide ointment and tacrolimus 0.1% ointment. Conclusion The combination of two therapeutic agents with different mechanisms of action likely resulted in the successful treatment of this usually resistant condition.
Size and specific activity of the UTP pool and overall rates of RNA synthesis in early mouse embryos.

Abstract Mouse embryos from the one-cell to the blastocyst stage were cultured for 2 hr in the presence of 5 μM [3H]uridine or 10 μM [3H]adenosine, and the size and specific activity of the UTP and ATP pools were determined by an Escherichia coli RNA polymerase assay using synthetic poly(dA-dT) as template. The total UTP pool increased in size and specific activity with development from 0.05 pmole (0.06% labeled) in the one-cell stage to 0.54 pmole (27% labeled) in the blastocyst stage. The total ATP pool remained relatively constant in size at about 1 pmole/embryo, but increased in specific activity from 2.6 to 52% from one-cell to blastocyst. The turnover of the [3H]UTP pool was also examined under pulse-chase conditions in eight-cell and morula-stage embryos. The UTP pool decayed with approximately first-order kinetics up to 20 hr of chase, but the rate of decay was slower in eight-cell embryos (t0.5 = 5.5 hr) than in morulae (t0.5 = 2.8 hr). The observed specific activities of the UTP pools were used to calculate the overall rates of uridine incorporation into acid-precipitable material during early development. The rate of uridine incorporation per embryo increased from 3.6 × 10−3 pmole/2 hr in the two-cell embryo to 1.8 × 10−1 pmole/2 hr in the blastocyst. The rate of RNA synthesis per cell over a 2-hr period was estimated at 2.5 pg in the two- to four-cell embryo, 5 pg in the eight-cell, and 10 pg in the morula-early blastocyst.
Experiencing programming assignments in CS1: the emotional toll

The constant comparative method was used to explicate the experience computing majors have with programming assignments in a CS1 course. Findings from a series of four interviews conducted with a purposeful sample of nine students revealed that the primary reflective experience with programming assignments was emotional. That is, the way students remembered and discussed their experiences with programming assignments was dominated by emotional experiences and reactions. We identified six stages whose dimensions capture the variation in students' emotional experiences with programming assignments. This paper reports the beginnings of analysis geared at developing a theory of students' programming assignment experience, rich in detail and grounded in student experience. When completed such a theory may lead to curricular supports, interventions, or tools, to help steer student experience away from the most harmful of emotional tolls.
Performance characterization studies of a flat field volume ECR ion source

An all-permanent-magnet, 6 GHz ECR ion source with a central flat magnetic field profile has been evaluated at the Holifield Radioactive Ion Beam Facility, Oak Ridge National Laboratory. This magnetic field configuration produces a large volume ECR zone when the input RF radiation is tuned in resonance with the central flat field, thereby increasing the probability for absorption of microwave power and, consequently, the hot electron population in the plasma volume. The magnetic field of the source can also be converted from the flat-B configuration to the traditional minimum-B configuration and vice versa. The studies show that the volume ECR configuration produced higher charge states and higher intensities for high charge states than the conventional minimum-B configuration.
Facing the Mirror: Older Women and Beauty Shop Culture

Facing the Mirror: Older Women and Beauty Shop Culture. Frida Kerner Furman. New York: Routledge Press, 1997. + 218 pp., photographs, notes, works cited, index.
Observation of defects associated with the Cu/W(110) interface as studied with variable-energy positrons

Positron emission from a W(110) single crystal has been studied as a function of copper coverage utilizing a variable-energy positron beam in conjunction with low-energy electron diffraction and Auger-electron spectroscopy. Evidence is presented that indicates that sig- p nificant positron localization occurs at defects associated with the Cu/W(110) interface, which can be removed by high-temperature annealing. Our data also reveal new information about the islanding of copper on tungsten, providing a reliable means of identifying and quantifying the relative two-dimensional coverage of the surface by these islands.