cssi/SciSciGPT-SciSciNet huggingface dataset:
Absence of carbohydrate in crystalline Fraction I protein isolated from tobacco leaves

Abstract By means of gas—liquid chromatography—mass spectra analyses, three-times recrystallized Fraction I protein from tobacco leaved contains less than 0.0005% carbohydrate and is therefore different from other species of protein which contain up to 5% carbohydrate.
Can a Pacifist Have a Conversation with Augustine? A Response to Alain Epp Weaver

Christians have historically differed as to whether the wrongness of an act is to be located in the objective character of the act or in the intention of the agent. By blurring this distinction, Alain Epp Weaver fails to see the real principle of consistency that unites Augustine's analyses of warfare and lying. Likewise, by not appreciating the fact that Augustine analyzes the wrongness of the act in terms of intention whereas Yoder analyzes its wrongness in terms of its objective character, Weaver proposes a conversation between two figures who lack the framework of shared assumptions that makes engagement in conversation possible.
Impact of molecular biology on Pseudomonas aeruginosa immunization

Persisting high mortalities from Pseudomonas aeruginosa infection have led to new strategies for treatment. In vitro and animal studies indicate that antibodies against P. aeruginosa antigens increase host defense against this infectious agent. The most effective immunogen is lipopolysaccharide (LPS) antigen; however, LPS vaccines are poorly tolerated. Furthermore, the LPS molecule does not lend itself well to production by genetic engineering. Pseudomonas aeruginosa protein antigens which might be amenable to recombinant DNA production are outer membrane proteins and exotoxin A, modified to decrease toxicity but maintain immunogenicity. Another strategy for immunization with anti-LPS P. aeruginosa antibodies is passive administration of either hyperimmune immunoglobulins (polyclonal) or monoclonal antibodies. Passive immunization offers the dual advantage of rapid protection or treatment and is well tolerated. Several monoclonal antibodies against LPS P. aeruginosa antigens have been described, including both murine and human types. Studies in animal models of infection indicate that P. aeruginosa monoclonal antibodies do protect, thus, the most feasible application of molecular biology to the problem of P. aeruginosa infection appears to be production of immunotype-specific monoclonal antibodies for immune therapy.
A VLSI architecture for a half-edge-based corner detector

Corner detection is a low-level feature detection operator that is of great use in image processing applications, for example, optical flow and structure from motion by image correspondence. The detection of corners is a computationally intensive operation. Past implementations of corner detection techniques have been restricted to software. In this paper we propose an efficient very large-scale integration (VLSI) architecture for detection of corners in images. The corner detection technique is based on the half-edge concept and the first directional derivative of Gaussian. Apart from the location of the corner points, the algorithm also computes the corner orientation and the corner angle and outputs the edge map of the image. The symmetrical properties of the masks are utilized to reduce the number of convolutions effectively, from eight to two. Therefore, the number of multiplications required per pixel is reduced from 1800 to 392. Thus, the proposed architecture yields a speed-up factor of 4.6 over conventional convolution architectures. The architecture uses the principles of pipelining and parallelism and can be implemented in VLSI.
A Study of Edge Characteristics of Sheared and Bent Steel Plate

The objective of this investigation was to gain an understanding of the phenomenon of edge crack formation during the bending of plate cut to size by shearing. The stages of sheared edge creation as well as the effect which blade gap and dullness have on the sheared edge properties were studied using the microhardness scanning technique.
Diagnosis and management of hyponatremia in acute illness.

Purpose of review Hyponatremia is the most common electrolyte disorder present in hospitalized patients. Acute and severe hyponatremia can cause significant morbidity and mortality. The present review discusses the epidemiology, causes, and a practical approach to the diagnosis and management of acute and chronic hyponatremia, including the appropriate use of hypertonic saline and potential future use of the new V2 vasopressin receptor antagonists in critically ill patients. Recent findings The increasing knowledge of aquaporin water channels and the role of vasopressin in water homeostasis have enhanced our understanding of hyponatremic disorders. Increased vasopressin secretion due to nonosmotic stimuli leads to decreased electrolyte-free water excretion with resulting water retention and hyponatremia. Vasopressin receptor antagonists induce electrolyte-free water diuresis without natriuresis and kaliuresis. Phase three trials indicate that these agents predictably reduce urine osmolality, increase electrolyte-free water excretion, and raise serum sodium concentration. They are likely to become a mainstay of treatment of euvolemic and hypervolemic hyponatremia. Summary The correct diagnosis and management of hyponatremia is complex and requires a systematic approach. Vasopressin receptor antagonists are potential tools in the management of hyponatremia. Further studies are needed to determine their role in the treatment of acute, severe, life-threatening hyponatremia as well as chronic hyponatremia.
A transmission electron microscopy investigation of sulfide nanocrystals formed by ion implantation

Ion implantation was used to form compound semiconductor nanocrystal precipitates of ZnS, CdS, and PbS in both glass and crystalline matrices. The precipitate microstructures and size distributions were investigated by cross-sectional transmission electron microscopy techniques. Several unusual features were observed, including strongly depth-dependent size variations of the ZnS precipitates and central void features in the CdS nanocrystals. The morphology and crystal structure of the nanocrystal precipitates could be controlled by selection of the host material. The size distribution and microstructural complexity were significantly reduced by implanting a low concentration of ions into a noncrystalline host, and by using multi-energy implants to give a flat concentration profile of the implanted elements.
Modelling wireless challenges

A thorough understanding of the network behaviour when exposed to challenges is of paramount importance to construct a resilient MANET (mobile ad hoc network). However, modelling mobile and wireless networks as well as challenges against them is non-trivial due to dynamic and intermittent connectivity caused by channel fading and mobility of the nodes. We treat MANETs as time-varying graphs (TVGs) represented as a weighted adjacency matrix, in which the weights denote the link availability. We present how centrality-based attacks could affect network performance for different routing protocols. Furthermore, we model propagation loss models that represent realistic area-based challenges in wireless networks.
Cerebellar AMPA/KA receptor antagonism by CNQX inhibits vestibuloocular reflex adaptation

Vestibuloocular reflex (VOR) performance and adaptation have been investigated during antagonism of cerebellar AMPA/quisqualate and kainate receptors (AMPA/KA) by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Injection of CNQX into the vestibulo-cerebellum of the goldfish before adaptation significantly inhibited and, at the highest dosage, completely prevented acquisition of adaptive reflex gain increases and decreases during a 3-h training period. Injection of CNQX before initiation of VOR adaptive training did not affect pre-adapted baseline performance of the reflex. Injection of CNQX, 1 to 2 h after the initiation of training did not alter the performance of adaptive gain increases that occurred before the injection. If injection of CNQX occurred at the end of adaptive training, there was an accelerated loss of the previously adapted gain changes during the retention period when the animal remained stationary in the dark. CNQX injection did not produce any permanent or long-term deficits, because goldfish could be retrained 48 h later to produce adaptive VOR gain changes similar to control animals. Thus, this work demonstrates that the AMPA/KA receptors located in the vestibulo-cerebellum of the goldfish are necessary for acquisition of short-term adaptive VOR gain increases and decreases. The deficit in adaptive capability was not the result of a deficit in performance, because CNQX did not inhibit an adaptive change that had already occurred as long as the adapting vestibular and visual stimulation continued. This adaptive performance could possibly be maintained by other glutamatergic (metabotropic) receptors located on the Purkinje cells. The retention of adapted gain increases and decreases after CNQX application was inhibited because AMPA/KA antagonism accelerated VOR gain loss after the completion of training when no vestibular or visual stimulation was present. Because the AMPA/KA receptors are located only in the molecular layer of the goldfish cerebellum, these results are, presumably, the result of AMPA/KA receptor antagonism at synapses located on the Purkinje cell dendrite tree.
Adoption of Sustainable Agricultural Practices: Diffusion, Farm Structure, and Profitability1

Cet article utilise des variables concernant la diffusion des pratiques innovantes ainsi que la structure de l'exploitation agricole pour expliquer les differences observees dans l'adoption par des fermiers du Montana de deux sortes de pratiques agricoles durables : celles impliquant une gestion intensive, et celles necessitant moins d'intrants en provenance du marche. Alors que la rentabilite percue constitue le plus important facteur affectant l'adoption dans les deux cas, les variables independantes ont des effets differents tant sur les opinions concernant le profit economique net que sur l'adoption, dans l'un et l'autre cas. Le type d'exploitation a joue un grand role dans l'adoption pour les fermes a faibles intrants, tandis que l'acces a l'information etait plus important pour les exploitations intensives
Conditional Instability of the First Kind Upside-Down

It is shown that entrainment leads to the generation of turbulence kinetic energy in a stratocumulus layer when the virtual temperature jump at the cloud top is weaker than a critical value. The critical value increases as the relative humidity of the air above the cloud top decreases. This result is interpreted as a criterion for the instability of the layer cloud to penetrative downdrafts. The role of the instability in determining the subtropical and tropical distributions of boundary-layer cloudiness is assessed.
Regulation of CD95 (Fas/APO-1)-induced apoptosis in human chondrocytes.

Objective To examine the role of nuclear factor κB (NF-κB) and caspases 3, 8, and 9 in CD95-mediated apoptosis of normal chondrocytes. Methods First-passage chondrocytes from normal human knee cartilage were stimulated with CD95 antibody, and cell death was determined by annexin V binding and by an enzyme-linked immunosorbent assay. Activation of caspases 3, 8, and 9 was measured by Western blotting, and their role in death signaling was evaluated using caspase-specific small peptide inhibitors. The influence of NF-κB was determined by electrophoretic mobility shift assay (EMSA) and proteasome inhibition–dependent blocking of the degradation of inhibitor of NF-κB. Results Low levels of NF-κB activity were detected by EMSA in unstimulated chondrocytes. NF-κB activity was increased in response to agonistic CD95 antibody. CD95 antibody–induced apoptosis was potentiated by the proteasome inhibitors MG-132 and PS1, and this was associated with a reduced nuclear translocation of NF-κB. Proteasome inhibitors also caused the induction of DNA fragmentation by tumor necrosis factor α. Procaspase 3 processing was enhanced by the proteasome inhibitor MG-132. Procaspase 8 was undetectable by immunoblotting in whole cell lysates of chondrocytes, but caspase 8 messenger RNA was detected by reverse transcription–polymerase chain reaction. Furthermore, apoptosis induced by CD95 stimulation and proteasome inhibitors was blocked by the caspase 8–specific inhibitor Ac-IETD-CHO. Processing of procaspase 9 was not observed, and inhibition of CD95-dependent cell death by the caspase 9 inhibitor Ac-LEHD-CHO was not significant. Conclusion These results suggest that CD95-dependent cell death is enhanced by NF-κB inhibition at and/or downstream of caspase 8 activation and that caspase 9 activation is not involved in CD95-mediated apoptosis in chondrocytes.
Diminished cardiac hypertrophy and muscle performance in older compared with younger adult rats with chronic atrioventricular block

The combined effect of advancing age and hemodynamic overload on cardiac muscle function has received little attention. In male, Sprague-Dawley rats, we studied the interaction of chronic atrioventricular heart block induced by transvenous electrocautery for 4-12 months (mean, 7 months) and age at study (12, 19 +/- 0.7, and 24 +/- 0.2 months) on cardiac hypertrophy and muscle function compared with age-matched, sham-operated controls. Hypertrophy was determined by the ratio of heart weight to tibial length. Muscle function was first determined from the mechanical variables of the isometric contraction of an excised, thin, left ventricular trabecular muscle bathed at 29 degrees C under a variety of calcium concentrations and stimulation patterns. Then, in the same muscles after disruption of membranes with Triton X-100, the force-pCa curve of the myofibrils was obtained. No hypertrophy occurred with aging in the control group, but alteration in hypertrophy with age occurred in the block group such that the youngest animals with block had the most hypertrophy (170%) and the oldest animals with block the least hypertrophy (120%). The tension developed by cardiac muscle and the duration of the isometric contraction were not affected by age in the control group but were significantly affected by age in the block group. The young animals with block had a markedly prolonged contraction duration and almost twice the developed tension compared with the older animals with block or with controls. The age-related difference in muscle contraction duration in the block group was associated with, and may have only been secondary to, the age-related difference in the extent of cardiac hypertrophy. For developed tension, the age-related difference in the block group could not be explained by differences in the extent of cardiac hypertrophy. Rather, this difference was attributable to both an increased myofibrillar force-generating capacity in the young block and to an impairment in excitation-contraction coupling in the old block. The results show that during long-term block, age exerted not only a significant effect on the extent of cardiac hypertrophy but also an independent effect on the developed tension of cardiac muscle.
QM/MM and free-energy simulations of deacylation reaction catalysed by sedolisin, a serine-carboxyl peptidase

Quantum mechanical/molecular mechanical free-energy simulations were performed to understand the deacylation reaction catalysed by sedolisin (a serine-carboxyl peptidase) and to elucidate the catalytic mechanism and the role of the active-site residues during the process. The results given here demonstrate that Asp170 may act as a general acid/base catalyst for the deacylation reaction. It is also shown that the electrostatic oxyanion hole interactions involving Asp170 may be less effective in transition state stabilisation for the deacylation step in the sedolisin-catalysed reaction compared to the general acid/base mechanism. The proton transfer processes during the enzyme-catalysed process were examined, and their role in the catalysis was discussed.
On the Discretization of Morphological Operators

We present new results on the problem of morphologically sampling binary images and image operators, thus enhancing the morphological sampling theory of Heijmans and Toet. These include sampling composite operators and approximating continuous translation invariant erosions, openings, and closings by discrete erosions, openings, and closings, respectively. The results presented in this paper have been already used in a theory of morphologically sampling random binary images modeled as random closed sets.
Diffusion of vibrationally excited molecules

Abstract A treatment is presented for the effect of intermolecular vibrational energy transfer on the diffusion coefficient of vibrationally excited molecules. An analytic treatment based on random walk statistics and a Monte Carlo type calculation have been performed. Both methods yield very similar results which correlate well with existing experimental studies. A hard sphere collision model is treated extensively with comparisons made to other internmolecular potentials. The results support the involvement of long range energy transfer in V → V interactions. The effect of temeprature on the diffusion coefficient of vibrationally excited molecules is calculated, with applications to the CO * 2 CO 2 system.
Fathering Across the Border: Latino Fathers in Mexico and the U.S.

This qualitative study gives voice to Latino fathers’ perceptions of their roles and values in family life by analyzing data collected from 32 Latino men residing in an Urban Mexican setting and both urban and rural settings in the U.S. The authors utilize a symbolic interactionist framework and ecological theory to illustrate the cultural nature of fatherhood constructions, the impact of immigration on patterns of change and continuity in paternal behaviors and values, and the importance of intergenerational influences in the formation of fatherhood perceptions. Fathers articulate the importance of education for their children, how they discipline, the impact of machismo, and other contrasting views of fathering in Mexico and the U.S. The findings support the idea of “generative fathering” to describe the resiliency of Latino fathers and the contributions they make to families, communities, and future generations. Implications for future research on fathers are suggested including the need to focus on the complex cultural nature of fatherhood constructions.
Disaster recovery considerations for academic institutions

Purpose – The purpose of this paper is to examine how an academic institution may more effectively respond to a disaster. In this particular situation the issues are being investigated in the context of a hurricane event. From 2005 to 2008 two hurricanes directly hit Lamar University in Beaumont, Texas. This paper examines the impact Hurricane Ike, the latter of these hurricanes, had on this academic institution. This research shares valuable insight into the vulnerabilities confronting academic institutions during natural disasters and highlights the lessons learned.Design/methodology/approach – This is a practitioner paper which applies survey data and qualitative interviews of key decision makers.Findings – Success in the aftermath of this disaster required serious consideration and forethought in institutional preparedness and continuity planning. Specifically, success relied on adequately prioritizing the recovery effort, effectively addressing communication and financial concerns, fostering administ...
An ellipse detection method from the polar and pole definition of conics

Abstract A new multistage Hough transform approach to the problem of ellipse detection in images is presented. The proposed approach is based on the polar and pole definition of conics and its advantage lies in avoiding the propagation of parameter estimation error over the successive stages of the Hough transform. The proposed method is capable of detecting partially visible ellipses, overlapping ellipses, and groups of concentric ellipses. A set of experimental results is presented to demonstrate these capabilities of the suggested approach.
Self-assembled monolayers of CF3-terminated alkanethiols on gold

Abstract The wettability and friction of self-assembled monolayers (SAMs) of terminally fluorinated alkanethiols, CF3(CH2)nSH with n=9–15, and their nonfluorinated analogs, CH3(CH2)nSH with n=9–15, were examined and compared. Surprisingly, the CF3-terminated monolayers were wetted more by water, glycerol and N,N-dimethylformamide than were the CH3-terminated SAMs. The terminally fluorinated films, however, exhibited significantly lower surface energies. The origin of these trends is discussed. The two types of monolayers were also studied by atomic force microscopy (AFM). Compared to the CH3-terminated SAMs, the fluorinated films revealed an approximately 3-fold increase in friction. A new model for the frictional response, which is based on the difference in size between the methyl and trifluoromethyl groups, is proposed.
Carbon monoxide negatively regulates NLRP3 inflammasome activation in macrophages

Inflammasomes are cytosolic protein complexes that promote the cleavage of caspase-1, which leads to the maturation and secretion of proinflammatory cytokines, including interleukin-1β (IL-1β) and IL-18. Among the known inflammasomes, the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3)-dependent inflammasome is critically involved in the pathogenesis of various acute or chronic inflammatory diseases. Carbon monoxide (CO), a gaseous molecule physiologically produced in cells and tissues during heme catabolism, can act as an anti-inflammatory molecule and a potent negative regulator of Toll-like receptor signaling pathways. To date, the role of CO in inflammasome-mediated immune responses has not been fully investigated. Here, we demonstrated that CO inhibited caspase-1 activation and the secretion of IL-1β and IL-18 in response to lipopolysaccharide (LPS) and ATP treatment in bone marrow-derived macrophages. CO also inhibited IL-18 secretion in response to LPS and nigericin treatment, another NLRP3 inflammasome activation model. In contrast, CO did not suppress IL-18 secretion in response to LPS and poly(dA:dT), an absent in melanoma 2 (AIM2)-mediated inflammasome model. LPS and ATP stimulation induced the formation of complexes between NLRP3 and apoptosis-associated speck-like protein, or NLRP3 and caspase-1. CO treatment inhibited these molecular interactions that were induced by LPS and ATP. Furthermore, CO inhibited mitochondrial ROS generation and the decrease of mitochondrial membrane potential induced by LPS and ATP in macrophages. We also observed that the inhibitory effect of CO on the translocation of mitochondrial DNA into the cytosol was associated with suppression of cytokine secretion. Our results suggest that CO negatively regulates NLRP3 inflammasome activation by preventing mitochondrial dysfunction.
CLARREO Science Applications: Infrared Spectra with On-orbit SI Traceability for Climate

This paper focuses on the climate science applications of the infrared sensor of the CLARREO mission. These applications are predicated on its on-orbit traceability, with empirically proven uncertainty, to the international definition of radiometric units.
A MICROSTRUCTURAL STUDY OF Co-20 wt.% Cr-10 wt.% Al USING APFIM AND TEM

Identification des phases presentes dans l'alliage avec une attention particuliere pour la caracterisation des precipites de seconde phase
Kinetic Mechanisms for Premixed, Laminar, Steady State Methane/Air Flames.

Abstract A number of kinetic schemes have been used to model premixed, laminar, one-dimensional methane/air flames. Seven such kinetic schemes, including two new models, are compared with one another and with experimental data. The two new models, one with 14 species and one with 20 species, both agree with the experimental data over a range of stoichiometries from lean to rich. All of the models show good agreement for lean to slightly rich flames. This does not validate any of the models, even for this limited range. Rather, it is shown that the quantities measured are fairly insensitive to much of the mechanism. Therefore, models with incorrect kinetics can agree with the experimental data. In particular, the contribution of the C2 species to methane combustion is examined. While these species are important, we conclude that there is insufficient information to determine quantitatively the effects of the C2 chemistry reactions.
Abstract A65: Toll-like receptor 3 signaling in ovarian cancer.

The purpose of this study is to examine the cytokine secretion (in vitro) and leukocyte infiltration profiles (in vivo) in response to Toll-Like Receptor 3 (TLR3) activation in murine epithelial ovarian carcinoma. Ovarian cancer is the most deadly gynecological neoplasm, typically treated with surgery and chemotherapy, and has a less than a 50% 5-year survival rate. Drug resistance develops frequently, and it is necessary to investigate more targeted therapies. Chronic inflammation, which is seen in many cancers, can render an immunosuppressive tumor microenvironment characterized by cytokines that promote leukocyte infiltration, which can potentiate angiogenesis, and subsequent tumor growth and metastasis. Pathways that can generate such inflammation are important to characterize as they may be targeted in the development of novel cancer therapeutics. One regulator of inflammation in some types of epithelial ovarian cancer is TLR3, a protein that senses dsRNA and activates NF-κB, a potent initiator of cytokine secretion. Although typically expressed in immune cells, TLR3 is also present in cancer cells, and may function to direct inflammation at the tumor site towards an immunosuppressive state capable of recruiting pro-angiogenic leukocytes. Using PCR, ELISA, western blot, and microarray experiments on siRNA-generated TLR3-knock-downs and control samples, we are characterizing the cytokine secretion profiles following TLR3 activation with synthetic dsRNA ligands. Furthermore, we will employ this ovarian cancer cell line (ID8) with C57BL/6 mice to generate transplantation tumors and determine the effects of TLR3 signaling on the leukocyte population and presence of angiogenic molecules at the tumor site using flow cytometry and immunohistochemistry. We have determined that treatment of ID8 epithelial ovarian carcinoma cells with TLR3 ligands poly (I:C) or poly (A:U) results in increased secretion of pleiotropic cytokines, such as CCL5 and IL6, that may potentiate leukocyte migration to the tumor site. In vivo studies with C57BL/6 mice will determine whether this TLR3-induced cytokine secretion in the tumor cells translates to the physiological environment and promotes leukocyte infiltration and angiogenesis. By elucidating the contribution of TLR3 to the recruitment of pro-angiogenic leukocytes in ovarian epithelial carcinoma, the results of this project may be useful in the development of anti-angiogenic therapies for certain ovarian tumors. Citation Format: Maria Muccioli, Michelle Pate, Fabian Benencia. Toll-like receptor 3 signaling in ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology: Multidisciplinary Science Driving Basic and Clinical Advances; Dec 2-5, 2012; Miami, FL. Philadelphia (PA): AACR; Cancer Res 2013;73(1 Suppl):Abstract nr A65.
Decreased cerebellar posterior vermis size in fragile X syndrome: Correlation with neurocognitive performance

We examined whether posterior vermis size is smaller in individuals with fragile X syndrome (fra X) than in control subjects and whether this decreased size is associated with cognitive performance. Cognitive and behavioral dysfunctions have been identified in fra X; however, underlying neuropathogenic mechanisms remain unclear. MRI was used to investigate the posterior fossa in 32 males with fra X, 28 males with other causes of cognitive disability (CD), and 38 males with normal development (ND) as well as and in 37 females with fra X and 53 female control subjects. Among females with fra X, neurocognitive correlates of posterior vermis size were examined. Posterior vermis size (cross-sectional area) in males with fra X was significantly smaller compared with CD and ND groups, particularly when corrected for intracranial area. Posterior vermis size corrected for intracranial area was significantly smaller in females with fra X compared with control subjects. Compared with males with fra X and non-fra X control subjects, posterior vermis size in females with fra X was intermediate. After statistically removing the effect of mean parental IQ, posterior vermis size predicted a significant proportion of the variance (10 to 23%) of performance on full-scale, verbal, and performance IQ; block design; categories achieved on the Wisconsin Card Sorting Test; and the Rey inventory score. The size of the posterior vermis is significantly decreased in fra X, more so in males than in females. In females with fra X, posterior vermis size predicts performance on selected cognitive measures.
Detection and quantitative analysis of early stage orthotopic murine bladder tumor using in vivo magnetic resonance imaging.

ABSTRACTPurpose: We evaluated in vivo magnetic resonance imaging (MRI) as a noninvasive method for early detection and quantitative measurements of superficial tumors in an orthotopic murine bladder tumor model.Materials and Methods: Murine bladder tumor cells were instilled into 25 mouse bladders and subsequently scanned with MRI 10, 14, 17 and 24 days after tumor inoculation. High quality T1-weighted spin-echo transverse images were obtained with 1.5 mm thick slices. Conditions for contrast agent instillation were optimized by evaluating varying concentrations of Gd-diethylenetetramine pentaacetic acid, water and air. Total tumor area in the largest bladder section on MRI was measured and compared quantitatively with actual tumor areas measured in whole mount bladder step sections.Results: Optimal MRI studies were obtained with intravesical instillation of 50 μl Gd-diethylenetetramine pentaacetic acid and 50 μl air. Overall 17 tumors in 11 mice were identified pathologically 10 days after tumor inoculat...
Effect of comonomers on melt processability of polyacrylonitrile

This work is concerned with the feasibility of achieving melt-processable polyacrylonitrile copolymer systems as precursors for the manufacture of carbon fibers. Identification of suitable comonomers and achieving the optimum content of the comonomer were some of the main objectives of this investigation. It was seen that methyl acrylate (MA) was found to be suitable for enabling the melt processing of polyacrylonitrile (PAN), in terms of melt viscosity, time stability, and char yield. Below 10 mol % of MA, the PAN copolymer exhibited no flowability, even at very low molecular weights (∼ 20,000). The long-range order inherently present in PAN is speculated to be broken down at a critical value of about 10% MA at 220°C in the PAN-based system, enabling its melt flowability. It was also seen that the incorporation of MA was seen to improve the temperature and molecular weight window of processability of the PAN system. The molecular weight cutoff for the 90/10 mol % acrylonitrile/methyl acrylate (AN/MA) system was about 50,000 at 220°C, whereas it was increased to about 100,000 in the presence of 15 mol % MA comonomer. Feasibility studies on the use of other comonomers such as higher acrylates and acrylamides were also conducted. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 69–83, 2002
Field and laboratory studies on alpine soil erodibility, southern Rocky Mountains, Colorado

Soil erodibility has been studied on the alpine tundra of Trail Ridge in the southern Rocky Mountains, Colorado. Field experiments were conducted using a portable rainfall simulator to estimate an erodibility index (grams of detached soil per unit area) at 71 sites. The index determined on eight soil types allowed discrimination of a high erodibility group (mean index of 18.9 g), moderate or transitional group (mean index of 10.1 g), and one low group (mean index of 4.5 g). Laboratory measurements of physical propertiesMdashtexture, water absorption capacity, organic carbon, and aggregationMdashwere compared with the erodibility index and results of simple and multiple regressions showed that 29 per cent of the variance in erodibility is explained by the measured variables, the strongest correlation (r=0.42) being associated with aggregation. Unexplained variability (71 per cent) may be due in part to unmeasured soil properties, non-linearity in the data, random processes, bias, and experimental error. These correlations represent a beginning in understanding factors influencing alpine soil erodibility. The results suggest that field measurement is still the most satisfactory method of estimating an erodibility index and that laboratory surrogates for this index are not readily applicable in this environment.
Cathode-fall development in low-pressure, parallel-plane hydrogen discharges

The temporal and spatial development of the cathode fall in pulsed, low-pressure hydrogen discharges is investigated using correlated measurements of the current, voltage, and optical emission. The results include the variation of relative emission probabilities versus time and position for the H(n=3) and ${\mathrm{H}}_{2}$(${\mathit{a}}^{3}$\ensuremath{\Sigma}) states. The behavior of the higher-energy electrons is inferred from the first negative band emission of ${\mathrm{N}}_{2}^{+}$ in mixtures of 2--3 % ${\mathrm{N}}_{2}$ in ${\mathrm{H}}_{2}$. Measurements are reported for final, i.e., quasi-steady-state, discharge currents of 10--100 mA for pressure times electrode spacing (pd) values of 1 and 3 Torr cm, where 1 Torr=133 Pa. The breakdown electric field E to gas density values vary from 1 kTd to 400 Td, where 1 Td=1\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}21}$ V ${\mathrm{m}}^{2}$. The ${\mathrm{H}}_{\mathrm{\ensuremath{\alpha}}}$ and the near-uv continuum emission data show the importance of heavy-particle excitation in the cathode-fall region. Representative transient current and voltage wave forms during the development of the cathode sheath are analyzed in terms of discharge and circuit parameters. During the period of rapid current growth at 3 Torr cm, transient emission wave forms for the uv continuum near the anode show a sudden drop that results from the collapse of the electric field. \textcopyright{} 1996 The American Physical Society.
Tensile Properties of Dyneema SK76 Single Fibers at Multiple Loading Rates Using a Direct Gripping Method

Ultra-high-molecular-weight polyethylene (UHMWPE) fibers such as Dyneema and Spectra are seeing more use in lightweight armor applications due to higher tensile strength and lower density compared with aramid fibers such as Kevlar and Twaron. Numerical modeling is used to design more effective fiber-based composite armor. For accurate simulation of ballistic impacts, material response such as tensile stress-strain of the composite constituents must be studied under experimental conditions similar to ballistic events. UHMWPE fibers are difficult to grip using adhesive methods typically used for other fibers due to low surface energy. Based on previous studies, the ability to grip UHMWPE fibers using traditional adhesive methods depends on fiber diameter and is limited to smaller diameter fibers that could affect reported stress values. To avoid diameter restrictions and surface energy problems, a direct gripping method has been used to characterize Dyneema SK76 single fibers at strain rates of 0.001 s-1, 1 s-1, and 1000 s-1. In this report, the dependence of fiber diameter and gage length on failure strength is discussed as well as success rate of failures in the gage section with this gripping technique. A comparison of the tensile properties with previous studies is also explored.
Rattling guest atoms in Si, Ge, and Sn‐based type‐II clathrate materials

We have studied the vibrational properties of some of the compounds based on the Type II silicon, ger- manium, and tin-based clathrate materials using LDA electronic structure methods. The lattices in these framework materials have open cages which can contain weakly bound guest impurities, and these guests produce local ("rattling") vibrational modes. Such modes may scatter the extended, heat carrying acoustic vibrational modes of the framework, potentially reducing the thermal conductivity. We present results for the vibrational spectra of the Type II clathrate compounds Na16Cs8Si136, Na16Cs8Ge136, and Cs24Sn136. We discuss trends in the vibrational spectra of the framework host material and of the localized, rattling fre- quencies of the guest modes as the host changes from Si to Ge to Sn. cages, and in which all framework atoms are in a four-fold-coordinated sp 3 bonding configuration. The local bonding in the framework of the clathrate lattices is thus similar to that in the diamond structure. However these lattices contain pentagonal rings, which makes their topology quite different from that in the diamond lattice. Further, the "cages" formed by the Group IV atoms can house "guest" atoms, and the choice of guest may be used to tune the properties of the material, including the vibrational proper- ties. Most of the clathrates which have been realized in the laboratory have been guest-containing com- pounds. These Group IV atom-based clathrate materials continue to be of considerable interest due to their unique transport properties. In particular, they have potential thermoelectric (1-4), superconducting (5- 8) and electro-optic applications (9, 10). Among the interesting properties the clathrate compounds pos- sess is their low thermal conductivity. The origin of this is the weak bonding of the guest atoms residing inside the cages. This results in localized ("rattler") vibrational modes which couple to the lattice modes by resonantly scattering the acoustic-mode, heat-carrying phonons of the host framework material (1), thereby lowering the thermal conductivity. Of the two clathrate lattice types, Group IV compounds with the Type I clathrate crystal structure have been the more thoroughly investigated both experimentally and theoretically. The pure framework mate- rials of this type have a simple cubic lattice structure with 46 atoms per unit cell and are denoted as
Review: Perinucleolar Structures

Several perinucleolar structures have been described in recent years. This review primarily summarizes recent studies regarding two of these structures, the perinucleolar compartment (PNC) and the Sam68 nuclear body (SNB). A number of studies have explored their ultrastructure and molecular components. Despite their different nuclear localizations, PNCs and SNBs share some common characteristics. They both are enriched with RNA binding proteins and nucleic acids and are predominantly localized to the periphery of the nucleolus. They are observed mostly in transformed cells, although prevalence differs among different cell types and cell lines. Their structural integrity is influenced by the transcriptional state of the cell. However, the functions of both the PNC and the SNB remain unknown. In addition to the PNC and SNB, a perinucleolar structure immunolabeled with an antibody to hnRNP L will be discussed.
Vectorization of the GEANT3 geometrical routines for a cyber 205

Abstract Simulation studies of high energy physics experiments consume now the largest portion of the CPU time required to analyze an experiment. This is mainly due to the increasing complexity of experimental apparatus and higher energies. We present here the first results from vectorizing the CERN detector simulation code GEANT3. Preliminary vectorization of just the geometrical part of GEANT3 applied to the calorimeter of experiment DO of Fermilab shows a factor of 3 gain in performance on a Cyber 205.
Spectral wave modeling in fringing reef environments

Abstract This study examines the implementation and validity of phase-averaged spectral models in describing wave transformation over fringing reefs. The wave breaking mechanism over the abrupt reef crest, dissipation due to bottom friction, and nonlinear energy transfer over the reef flat set the problem apart from general applications in non-tropical settings. The Simulating Wave Nearshore (SWAN) model, which is widely used in coastal engineering applications, has embedded parameterizations of these surf-zone processes for examination. In addition, we extend the model to include a recently implemented bottom-friction source term for tropical reefs. Comparisons of model predictions with laboratory and field observations over fringing reefs identify promising wave-breaking and bottom-friction parameterizations for calibration. The calibrated parameterizations enable SWAN to reproduce the observed wave height and setup and extend the applicability of spectral models to fringing reef environments. SWAN, however, lacks the parameterization to describe the nonlinear energy transfer toward the infra-gravity band that was observed in the laboratory and field studies.
The Politics of Location: Where Am I Now?

In this article, through the use of several narrative devices, the author reflects on how the past retrains in the present and shapes the future. Using the metaphor of locating oneself on a writing-map, she writes about fact and fiction, autobiography, and coauthor-ship. The author finds that writing about one's spatial-temporal locations is a powerful tool for the relocation of the self - physically, symbolically, and emotionally
Expected query complexity of symmetric boolean functions

The problem of finding optimal querying policy, for expected query complexity of symmetric boolean threshold functions was solved in [1] in the context of collocated networks. In this paper, instead of considering the optimal policy to compute the functions, we define the problem of verification of the function value. We use this idea to provide a simpler proof of the optimal querying policy for threshold functions. The method is more generic and is extended to delta and some other symmetric functions. We also provide some partial results for interval functions and finally address a question posed in [1]. Recently we have extended these results to any symmetric function of boolean inputs, which we mention at the end.
Evidence for a Functional Monomeric Form of the Bacteriophage T4 Dda Helicase Dda DOES NOT FORM STABLE OLIGOMERIC STRUCTURES

The active form of many helicases is oligomeric, possibly because oligomerization provides multiple DNA binding sites needed for unwinding of DNA. In order to understand the mechanism of the bacteriophage T4 Dda helicase, the potential requirement for oligomerization was investigated. Chemical cross-linking and high pressure gel filtration chromatography provided little evidence for the formation of an oligomeric species. The specific activity for ssDNA stimulated ATPase activity was independent of Dda concentration. Dda was mutated to produce an ATPase-deficient protein (K38A Dda) by altering a residue within a conserved, nucleotide binding loop. The helicase activity of K38A Dda was inactivated, although DNA binding properties were similar to Dda. In the presence of limiting DNA substrate, the rate of unwinding by Dda was not changed; however, the amplitude of product formation was reduced in the presence of increasing concentrations of K38A Dda. The reduction was between that expected for a monomeric or dimeric helicase based on simple competition for substrate binding. When unwinding of DNA was measured in the presence of excess DNA substrate, addition of K38A Dda caused no reduction in the observed rate for strand separation. Taken together, these results indicate that oligomerization of Dda is not required for DNA unwinding.
Ultrathin HfO 2 films grown on Silicon by atomic layer deposition for advanced gate dielectrics applications

We report on growth behavior, structure, thermal stability and electrical properties of ultrathin (<10 nm) hafnium oxide films deposited by atomic layer deposition using sequential exposures of HfCl4 and H2O at 300°C on a bare silicon surface or a thin thermally grown SiO2-based interlayer. Compared to good quality continuous films deposited on SiO2 surfaces, HfO2 deposited on HF-last treated Si surfaces show a non-uniform, island-like morphology and poor electrical properties due to poor nucleation on H-terminated Si. As-deposited films have a significant amorphous component and undergo crystallization to a monoclinic phase above ∼500°C. Crystallization behavior is found to be dependent on film thickness with higher crystallization temperatures for thinner films. HfO2 on an ultrathin SiO2 interlayer shows good electrical properties with gate leakage current reduced by a factor of 103 -104 with respect to conventional SiO2 gate dielectrics which justifies its consideration as a candidate for high-K dielectric for future CMOS devices.
Experimental Characterization of Structural Features during Radical Chain Homopolymerization of Multifunctional Monomers Prior to Macroscopic Gelation

An experimental methodology is presented to characterize the evolution of structural heterogeneities in cross-linked polymer networks formed by homopolymerizations of multifunctional monomers. In particular, intramolecularly cross-linked macromolecules (ICMs) were synthesized by individual initiation events and characterized. A set of complementary experimental tools, including atomic force microscopy (AFM), size exclusion chromatography, light scattering, and NMR, is used to provide information about size, intramolecular cross-link density, and kinetic chain length for poly(methacrylic anhydride) (PMA) ICMs. Images of PMA ICMs, which contain ca. 1000−2000 monomers, on average, are captured with AFM. Varying polymerization temperature from −13 to 70 °C led to an increase in the apparent size of the ICMs and an increase in the fraction of doubly reacted monomers. Furthermore, ICMs synthesized in the presence of tetraethylthiuram disulfide (TED), a photoiniferter precursor, were characterized. Iniferter-med...
The occurrence of N,N-Dimethylethanolamine in the 5-O-β-d-Galactofuranosyl-containing exocellular glycopeptide of Penicillium charlesii

Penicillium charlesii incorporates 3 H from [1- 3 H]ethanolamine, 14 C from [2- 14 C]ethanolamine, or 14 C from l -[CH 3 - 14 C]methionine into an exocellular glycopeptide (peptidophosphogalactomannan) previously shown to be devoid of methionine and to contain ethanolamine [Rick, P. D., Drewes, L. R., and Gander, J. E. (1974) J. Biol. Chem. 249:2073–2078]. Treatment of the glycopeptide with 0.4 n NaOH releases about 35% of the radioactivity as a low molecular weight substance containing 14 C or 3 H derived from methionine or ethanolamine. This substance was identified as dimethylethanolamine. About 5% of the radioactivity elutes with a mannose-containing oligosaccharide in a position expected for mannotetraose substituted with phosphoryldimethylethanolamine. The remainder of the radioactivity (about 60%) was associated with phosphogalactomannan region. In companion experiments with 32 P-labeled glycopeptide, 95% of the 32 P remained with the phosphogalactomannan and the other 5% was associated with the mannotetraose fraction. Smith degradation of glycopeptide labeled from [ 14 C]methionine and [ 3 H]ethanolamine resulted in two major radioactive substances with approximately equivalent 3 H/ 14 C ratio. These fractions contained dimethylethanolamine. Acetolysis of the glycopeptide labeled with 3 H from ethanolamine or 14 C from methionine or 32 P resulted in the recovery of the majority of the radioactivity in the aqueous phase. In contrast, the acetylated saccharides are recovered from the CHCl 3 phase. This treatment cleaves the phosphodimethylethanolamine from the saccharides. We conclude that the glycopeptide contains phosphoryldimethylethanolamine attached to at least two distinct positions of the mannan; that attached to C(6) being stable to alkali and that attached to C(2), C(3), or C(4) being unstable. Approximately 5% of the phosphorus and dimethylethanolamine may be associated with a mannotetraose attached through a seryl or threonyl group to the polypeptide.