cssi/SciSciGPT-SciSciNet huggingface dataset:
La teoria poetica di Mario Luzi

La produzione saggistica di Mario Luzi offre un estensivo contributo circa la riflessione della letteratura. In questo lavoro l’analisi si concentra su due punti in particolare. Il primo e il metodo che Luzi utilizza nel conseguire i suoi risultati teorici. La rilevanza di esso risiede nel fatto che il poeta riesce a costruire una teoria letteraria radicandola profondamente nella propria esperienza di scrittore. Il secondo punto, invece, vuole mettere in luce i contenuti stessi di questa teoria. Per questo motivo si analizzano alcuni scritti chiave del poeta che propongono un approccio e dei contenuti nuovi e originali nella discussione della natura dell’opera letteraria.
The technology of the ion cyclotron range of frequencies

Plasma heating in the ion cyclotron range of frequencies (ICRF) is the least expensive means of accomplishing auxiliary heating in fusion experiments. RF systems comprise two major elements: the transmitter and the antenna. The state of the art for the transmitter is already at the megawatt level. The technology of the antenna is strongly coupled to the plasma character. Typically, these antennas are designed to operate at a high power density (1.2 kW/cm/sup 2/) with an efficiency of 96%. ICRF technology and options have improved over the past few years, owing to development and experiments; however, the optimal combination of options can be defined only when results from confinement experiments and test facilities are in hand. 19 refs., 5 figs., 1 tab.
The Neutronic Analysis for the LBM/LOTUS Experiment

The LBM/LOTUS experimental results will be compared with the calculated values using the MCC in early 1986 based on the MCNP and DOT models described. The comparison will allow a testing of the features of the MCC in a simplified situation, in preparation for the ultimate experiment of the LBM on TFTR.
Franz Boas ‐ Social Activist: The Dynamics of Ethnicity

Franz Boas—Social Activist: The Dynamics of Ethnicity. Marshall Hyatt. Contributions to the Study of Anthropology, Number 6. New York:Greenwood Press, 1990. xxii. 174 pp.
Querying complex structured databases

Correctly generating a structured query (e.g., an XQuery or a SQL query) requires the user to have a full understanding of the database schema, which can be a daunting task. Alternative query models have been proposed to give users the ability to query the database without schema knowledge. Those models, including simple keyword search and labeled keyword search, aim to extract meaningful data fragments that match the structure-free query conditions (e.g., keywords) based on various matching semantics. Typically, the matching semantics are content-based: they are defined on data node inter-relationships and incur significant query evaluation cost. Our first contribution is a novel matching semantics based on analyzing the database schema. We show that query models employing a schema-based matching semantics can reduce query evaluation cost significantly while maintaining or even improving result quality. The adoption of schema-based matching semantics does not change the nature of those query models: they are still schema-ignorant, i.e., users express no schema knowledge (except the labels in labeled keyword search) in the query. While those models work well for some queries on some databases, they often encounter problems when applied to complex queries on databases with complex schemas. Our second contribution is a novel query model that incorporates partial schema knowledge through the use of schema summary. This new summary-aware query model, called Meaningful Summary Query (MSQ), seamlessly integrates summary-based structural conditions and structure-free conditions, and enables ordinary users to query complex databases. We design algorithms for evaluating MSQ queries, and demonstrate that MSQ queries can produce better results against complex databases when compared with previous approaches, and that they can be efficiently evaluated.
Fracture tolerance analysis of the solid rocket booster servo-actuator for the space shuttle

The results of an evaluation of the fracture tolerance of three components of the thrust vector control servo-actuator for the solid rocket booster of the space shuttle are described. These components were considered as being potentially fracture critical and therefore having the potential to fall short of a desired service life of 80 missions (that is, a service life factor of 4.0 on a basic service life of 20 missions). Detailed stress analysis of the rod end, cylinder, and feedback link components was accomplished by three-dimensional finite-element stress analysis methods. A dynamic structural model of the feedback system was used to determine the dynamic inertia loads and reactions to apply to the finite-element model of the feedback link. Twenty mission stress spectra consisting of lift-off, boost, re-entry, and water impact mission segments were developed for each component based on dynamic loadings. Experimental fracture response data da/dN, K I c , and K c were used for the structural alloys of the actuator components. These alloys were Inconel 718, 17-4 PH (H1025), 6061-T651, 2024-T851 (T351), and A286. Linear fatigue crack growth life and residual strength analyses were performed on the component critical locations using the Forman da/dN equation and CRACKS III computer code. Most components were determined to have the potential of reaching a service life of 80 missions or service life factor of 4.0.
Histidine regulation in Salmonella typhimurium. 13. Nucleotide sequence of histidine transfer ribonucleic acid.

Abstract There is only one species of histidine-specific transfer RNA detectable in Salmonella typhimurium. Its sequence is -G-G-U-G-G-C-U-A-Us4-A-G-C-U-C-A-G-D-D-G-G-D-A-G-A-G-C-C-C-U-G-G-A-U-U-G*-U-G-Am2-ψ-ψ-C-C-A-G-U-U-Gm7-U-C-G-U-G-G-G-T-ψ-C-G-A-A-U-C-C-C-A-U-U-A-G-C-C-A-C-C-C-C-(C)-A. Escherichia coli produces a histidine tRNA with an identical sequence. The presence of the C in parentheses is uncertain from our analysis. G* is probably identical with the modified G found in the analogous position in E. coli tyrosine tRNA.
Multisegment Nd:glass amplifiers for the National Ignition Facility and the French Laser Megajoule

Summary form only given. In this paper, we describe the Nd:glass laser amplifier mechanical design and report the results of both modeling and experiments in support of NIP and LMJ amplifier development. Gain measurements performed on a 2/spl times/2 multisegment amplifier using 4.3-cm-bore flashlamps have demonstrated 3% storage efficiencies. Ray-trace calculations agree well with the measured gain distributions.
PLANT MACROFOSSIL METHODS AND STUDIES | Megafossils

Megafossil wood (identifiable specimens of wood weighing tens of grams to tens of kilograms) is found beyond the modern limits of trees in a number of regions along the Arctic treeline. Identification of these fossils using wood anatomy and affixing chronological control using radiocarbon dating or dendrochronology provides a spatially explicit technique for reconstructing the minimum arrival time of trees in the far north and the minimum distance of northward advance of treeline in the Holocene. Many regions in Eurasia and some in North America have provided wood megafossil evidence indicating that treeline was located north of its modern position, or at higher elevations, during the early to mid-Holocene.
The effects of wind and nonlinear damping on rogue waves and permanent downshift

Abstract In this paper we investigate the effects of wind and nonlinear damping on permanent downshift and the formation of rogue waves in the framework of a HONLS model. Wind effects are incorporated by including a uniform linear damping/forcing term in the model. The strength of the wind, Γ , is allowed to vary as well as wind duration. Determining permanent downshift is not straightforward and we propose a criteria for permanent downshift related to our numerical experiments. We consider large ensembles of initial data for modulated unstable Stokes waves with N = 1 , 2 , 3 unstable modes. In the nonlinear damped HONLS evolution we find that permanent downshift is observed whenever the strength of the nonlinear damping β > 0.1 . Notably, rogue waves typically do not develop after the time of permanent downshift, implying that a downshifted sea-state does not allow for any further rogue waves. Incorporating wind effects into the nonlinear damped HONLS model, we find that damping by the wind weakens downshifting while forcing by the wind enhances downshifting. The proximity of the initial data to unstable plane waves impacts the characteristic features of the rogue waves in the nonlinear damped HONLS evolution. We find that as the initial data is chosen closer to the plane wave, the maximum strength, number, and lifetime of rogue waves increase while the time of permanent downshift decreases. Alternatively, we show that the greater the wave strength, the more rogue waves, or the longer their lifetime, the earlier permanent downshift occurs.
Cutaneous spindle cell carcinoma misdiagnosed as atypical fibroxanthoma based on immunohistochemical stains.

Poorly differentiated spindle cell neoplasms pose a diagnostic challenge for dermatopathologists because of a lack of specific morphologic features on standard histopathology. Further characterization with immunohistochemical (IHC) studies is frequently required. We present a fatal case of spindle cell squamous cell carcinoma (SCC) misdiagnosed as atypical fibroxanthoma (AFX) based on a limited panel of IHC markers.
Relationship of Larval Density and Instars of Pseudaletia unipuncta to Rice Leaf Feeding

Larvae of Pseudaletia unipuncta (Haworth) (Lepidoptera: Noctuidae) in the laboratory consumed an average of 267.7 cm2 of rice foliage over an average 24.3-day developmental period. Of the total amount consumed, 96% was eaten during the last 10 to 12 days (5th and 6th instars). Feeding damage in the field was generally found on the distal portion of rice leaves. More larvae were found in fields with a dense rice plant stand than in areas with a thinner plant stand. Defoliation of rice plants was highly correlated with larval density. The greatest number of larvae observed in the field was 0.37 larvae per plant.
Meropenem in elderly and renally impaired patients.

The safety profile of meropenem in the elderly (aged > 65 years, n = 843) and/or renally impaired (creatinine clearance < 51 ml/min, n = 436) was assessed by evaluating data from 26 phase III studies which compared the use of meropenem (0.5 or 1.0 g, i.v. every 8 h) with other antimicrobial agents in patients with bacterial infections. The overall pattern and frequency of adverse events following meropenem therapy in the elderly and/or renally impaired were similar to those in younger and/or non-renally impaired cohorts and to imipenem/cilastatin and injectable third generation cephalosporins. Both dosages of meropenem (0.5 and 1.0 g, i.v. every 8 h) were generally well tolerated. There was no clinically significant mean change in indicators of renal flux between baseline and the end of treatment in any patient sub-group. Importantly, meropenem-related seizures were rare (0.1%), even in patients with renal impairment. In summary, meropenem has an excellent safety profile and is therefore suitable for use in elderly and/or renally impaired patients.
Optimizing Performance On Unreliable, Dynamic Networks

This paper discusses link-assignment and adaptive routing algorithms that have been developed for networks consisting of a large number of mobile nodes having directive links. We focus on the special case where data rates are large (tens of Mbits/sec) and the propagation delay between nodes may be large compared to packet transmission delay. In such circumstances, queue sizes at store-and-forward nodes can become extravagant if retransmissions are required because of lost or damaged packets. The algorithms employ techniques that provide a high probability of successful message delivery on the first transmission attempt in the unreliable network. The link-assignment algorithm builds and maintains a link topology that provides multiple node-disjoint paths between each source and destination. Decisions regarding topology changes are also based on link permanency and ability to carry the anticipated traffic load. The adaptive routing algorithm establishes routing tables for multiple independent paths that are maximally node-disjoint between all sources and destinations. Load splitting techniques are used to achieve better load balancing and also to provide a mechanism for rapid adaptation around failed links. All algorithms are distributed in the sense that each node makes independent decisions. Heuristic optimization techniques are used to reduce computation time to within affordable limits. The routing algorithm also responds well to transients in traffic loading.
Breast cancer: origins and evolution

Breast cancer is not a single disease, but rather is composed of distinct subtypes associated with different clinical outcomes. Understanding this heterogeneity is key for the development of targeted cancer-preventative and -therapeutic interventions. Current models explaining inter- and intratumoral diversity are the cancer stem cell and the clonal evolution hypotheses. Although tumor initiation and progression are predominantly driven by acquired genetic alterations, recent data implicate a role for microenvironmental and epigenetic changes as well. Comprehensive unbiased studies of tumors and patient populations have significantly advanced our molecular understanding of breast cancer, but translating these findings into clinical practice remains a challenge.
Intrastriatal and intraventricular infusion of brain-derived neurotrophic factor in the cynomologous monkey : distribution, retrograde transport and co-localization with substantia nigra dopamine-containing neurons

Abstract The distribution and retrograde transport of brain-derived neurotrophic factor was examined using magnetic resonance imaging guided stereotaxic intracerebroventricular and intrastriatal infusion in the cynomologous monkey. Two intracerebroventricular animals were infused with brain-derived neurotrophic factor at a dose of 3 μg/h for 21 and 28 days. A third intracerebroventricular animal received sequential infusions of 15, 30 and 60 μg/h brain-derived neurotrophic factor each for seven days using an Alzet 2002 minipump. For the multiple intrastriatal animals ( n = 5) a dose of 3 μg/h was infused into each site. One intrastriatal monkey was infused with vehicle solution of 10 mM phosphate-buffered saline pH 7.4 for 14 days resulting in no brain-derived neurotrophic factor immunoreactivity. Following the lower dose intracerebroventricular infusion, brain-derived neurotrophic factir immunoreactivity was confined to the ventricular ependymal layer. In the sequential higher dose intracerebroventricular case, the cannula was located mainly within the lateral ventricle, although there was damage to the ependymal wall and adjacent caudate nucleus. Brain-derived neurotrophic factor immunoreactivity revealed spread of injectate within the ipsilateral and to a lesser extent the contralateral caudate nucleus, septum, orbital cortex and ventricular ependymal wall. In this case, retrogradely labelled brain-derived neurotrophic factor neurons were found within the parafascicular thalamus and substantia nigra, pars compacta, as well as within cortex, vertical limb of the diagonal band and nucleus basalis. Brain-derived neurotrophic factor intrastriatal infusion retrogradely labelled perikarya within sensory motor cortex, parafascicular thelamus and substantia nigra, pars compacta. Sections from these cases dual-immunoreacted for brain-derived neurotrophic factor and tyrosine hydroxylase, the synthesizing enzyme for dopamine, revealed a subpopulation of pars compacta dopaminergic neurons which contained retrogradely transported brain-derived neurotrophic factor. These findings indicate that a select subgroup of nigral dopamine neurons retrogradely transport brain-derived neurotrophic factor in the primate. Furthermore it remains to be determined whether select nigral cells are responsive to the trophic influences of brain-derived neurotrophic factor in the normal and neuropathologic condition.
Neurodegenerative Differences in the Retinas of Male and Female Patients with Type 2 Diabetes

PURPOSE The purpose of our study is to determine whether neuroretinal function, measured by the multifocal electroretinogram, differs between males and females with type 2 diabetes and no retinopathy. METHODS This study included 70 eyes from 70 adult subjects (14 control males, 22 control females, 16 males with type 2 diabetes, and 18 females with type 2 diabetes). A template-scaling technique was used to obtain first-order P1 implicit times and N1-P1 amplitudes from photopic multifocal electroretinograms within the central 45 degrees. RESULTS The males with type 2 diabetes were significantly more abnormal than their female counterparts in two separate analyses of local neuroretinal function. First, the total number of retinal locations with an abnormally delayed implicit time (z score ≥ 2) was higher (P < 0.001) in the diabetic males (482 locations = 29.2%) compared to the diabetic females (298 locations = 16.1%). Second, in the response topographies that consisted of 103 means of local implicit times for each group, the diabetic males were significantly delayed (P < 0.025) at 23 corresponding positions (22.3%) compared to the diabetic females. At the same time, no corresponding stimulus locations were significantly delayed in the diabetic females compared to the diabetic males. CONCLUSIONS Neuroretinal function is more abnormal in males than in females for adults with type 2 diabetes and no retinopathy. These results suggest that, relative to males, females may have some protection from, or resistance to, neurodegenerative changes that precede the development of background retinopathy in type 2 diabetes.
Alcohol consumption in pregnant, black women is associated with decreased plasma and erythrocyte docosahexaenoic acid

Background: Inner-city, black women are among those groups that are at higher risk for having infants with fetal alcohol spectrum disorders that can include life-long neurobehavioral and cognitive impairments. Chronic alcohol consumption can decrease amounts of docosahexaenoic acid (DHA), a fatty acid that is essential for optimal infant neural and retinal development in a variety of tissues. Methods: Black women who presented at an inner-city antenatal clinic for their first prenatal visit were recruited into a longitudinal, observational study. Alcohol intake was determined by a structured interview. Participants provided blood specimens and completed food frequency surveys at 24 weeks of gestation, infant delivery, and 3 months postpartum. Fatty acid composition analyses were completed on 307, 260, and 243 for plasma and 278, 261, and 242 erythrocyte specimens at 24 weeks of gestation, delivery, and 3 months postpartum, respectively. Results: Proportion of drinking days at the first prenatal visit was associated with decreased DHA in plasma and erythrocytes throughout the study. This association was the strongest at 24 weeks of gestation. In addition, an interaction between proportion of drinking days at the time of conception and ounces of absolute alcohol per drinking day at the time of conception was detected and demonstrated that, in daily drinkers, high intakes of alcohol are associated with decreased DHA and arachidonic acid (AA) concentrations in plasma. Conclusions: Frequent and high intakes of alcohol that have been previously associated with fetal alcohol spectrum disorders are also associated with decreased maternal DHA and AA plasma concentrations. The present findings indicate that maternal DHA deficiency is associated with high-risk drinking and may contribute to the mechanism(s) of alcohol-related neurodevelopmental disorders.
Symmetric groups as automorphisms of some commutative algebras

Let A be a commutative (nonassociative) algebra over a field k satisfying the condition (*): A has a basis xi,..., x,, n>2, such that x,x,= (n1) xi, 1 N + 1, and in [l] Harry Allen determined Aut(A) for the remaining case. Combining [ 1 ] and [2], we have
The Missing Blueprint for Progress, or What the Extension Futures Report Failed to Do

In a nutshell, I found the report of the Futures Task Force to the Extension Committee on Organization and Policy (ECOP), entitled "Extension in Transition: Bridging the Gap Between Vision and Reality," to be an insightful indictment of extension. It also widely misses the mark. When viewed in toto the report does present a reasonably accurate assessment of many problems and issues currently facing extension, offers some useful suggestions as to the types of things that could be done to deal with these problems, and fails completely in setting forth a meaningful way to bring about desired change. In the end, the report is trapped by its own criticism. The task force would have been well advised to give more heed to the warning of Neil Sampson when he wrote, "some of Extension's most notable successes in the past predict its future least accurately." My intent is to do four things: (a) highlight the issues identified in the report that I believe typify problems that extension must resolve in order to carry out a viable educational mission in the years ahead; (b) characterize the essence of what the task force appears to believe that extension ought to do to resolve its problems, as implied by its recommendations and supporting rationale; (c) assess what extension is likely to look like in the future if the recommendations are carried out literally; and (d) present an alternative strategy that I believe has greater potential for bringing about a relevant mission for extension education. The latter point is, I suggest, what the task force failed to do in its obvious attempt not to offend extension as we know it now.
Research on Resistance to Cancer Drug Gleevec

In a study of 11 patients with advanced-stage chronic myeloid leukemia (or Philadelphia chromosome positive acute lymphoid leukemia) who relapsed during treatment with the kinase inhibitor STI-571 (Gleevec), our group reported BCR-ABL gene amplification and kinase domain mutation as potential mechanisms of resistance ([1][1]). Specifically, three patients had gene amplification and six patients had a point mutation resulting in a threonine-to-isoleucine change at amino acid position 315 (T315I) of the ABL kinase domain. Subsequently, Technical Comments were published from two groups (Barthe et al. and Hochhaus et al. ) who reported that they were unable to detect the T315I mutation in such patients ([2][2]). Both groups did, however, detect kinase domain mutations in a different residue in two patients (E255K and E255V). As described in abstracts for the 2001 Annual Meeting of the American Society of Hematology, four groups, including Hochhaus and colleagues ([3][3]), have now detected patients with the T315I mutation ([3][3], [4][4]). All the groups, including ours, have detected additional kinase domain mutations. The overall contribution of these mutations versus other potential resistance mechanisms remains to be defined. 1. [↵][5]1. M. E. Gorre 2. et al. , Science 293, 876 (2001). [OpenUrl][6][Abstract/FREE Full Text][7] 2. [↵][8]1. C. Barthe 2. et al. , Science 293, 2163 (summary) (2001). Full text available at ; A. Hochhaus et al., ibid. ; M. E. Gorre et al., ibid. 3. [↵][9]1. S. Kreil 2. et al. , Abstracts for the 43rd Annual Meeting of the American Society of Hematology, Orlando, FL, 7 to 11 December 2001, abstr. 1823. Available at . 4. [↵][10]1. S. Branford 2. et al. , in (3), abstr. 3204; N. Shah et al., . [1]: #ref-1 [2]: #ref-2 [3]: #ref-3 [4]: #ref-4 [5]: #xref-ref-1-1 "View reference 1 in text" [6]: {openurl}?query=rft.jtitle%253DScience%26rft_id%253Dinfo%253Adoi%252F10.1126%252Fscience.1062538%26rft_id%253Dinfo%253Apmid%252F11423618%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [7]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Mzoic2NpIjtzOjU6InJlc2lkIjtzOjEyOiIyOTMvNTUzMS84NzYiO3M6NDoiYXRvbSI7czoyNToiL3NjaS8yOTQvNTU0OC8xODM0LjIuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9 [8]: #xref-ref-2-1 "View reference 2 in text" [9]: #xref-ref-3-1 "View reference 3 in text" [10]: #xref-ref-4-1 "View reference 4 in text"
In war and peace: Women and conflict prevention

Conflict prevention is not a new concept, but it has generated new interest in recent years among both academics and policymakers. Despite a significant amount of discussion and analysis relating to conflict prevention strategies, there has been minimal attention focused on the capacities of women in this area. The purpose of this article is to examine the frameworks that have been proposed for conflict prevention, to survey some of women's recent conflict prevention‐related activities around the world and to consider how women's initiatives can be incorporated into the development of effective conflict prevention policies at the regional and international levels.
Diffusion and flow transfer of theophylline across the blood-brain barrier: Pharmacokinetic analysis

Two possible schemes describing the transfer of theophylline across the blood-brain barrier are investigated. The first, the "diffusion only model," assumes that the rate of transfer is proportional to the difference in free drug concentration in the serum and cerebrospinal fluid. The second, the "diffusion and flow model," has the added feature that drug may be transferred from the CSF to the blood by the continuous secretion of CSF into the blood. Comparison of the results of nonlinear regression for the two proposed schemes indicated that the "diffusion and flow" model best describes the transfer process. The analysis indicates that the parameters obtained for the "diffusion and flow" model are physiologically meaningful.
Chlamydial infections: The mother-infant connection

During the past decade, new knowledge about the clinical significance of Chlamydia trachomatis in adult and pediatric infections, has mandated a greater awareness of this etiologic agent by gynecologists, obstetricians, and pediatricians. Significant repercussions on the medical, sociological, and public health levels have resulted. This article will focus on the maternal-infant association of chlamydial infections during the perinatal period, at birth, and the subsequent childhood years. As shown in Table 1, an ever-increasing spectrum of diseases has been documented for Chlamydia infections. In addition, possible causal relationships, include spontaneous abortion, prematurity, stillbirth, neonatal death, endocarditis, adult pneumonia (immune-suppressed and community-acquired), urethral syndrome, urinarytract infection, and pharyngitis.
Intraventricular N-acetyl-L-glutamate induces retrograde amnesia in chicks

Abstract Two-day-old chicks were injected intraventricularly with saline or an N-acetyl-L-glutamate solution. The amino acid analog produced retrograde amnesia without concomitant electrophysiological seizure activity. A mechanism involving the disruption of activity at memory-related glutamate synapses was suggested for the observed amnestic effect.
Structural Inversion of Micellar Block Copolymer Thin Films

Polystyrene-b-poly(1,1‘,2,2‘-tetrahydroperflurooctyl methacrylate) (PS-b-PFOMA) thin films, cast from a cosolvent mixture of Freon 113 and toluene onto Si/SiOx substrates, form spherical micelles; the cores are composed of PFOMA chains with a PS corona. Upon exposing the films to supercritical CO2 (Sc-CO2), the morphology inverts, wherein the core is composed of PS chains and the PFOMA chains constitute the corona. In each case, the free surface and polymer/substrate layers are enriched with PFOMA. The size of the PS cores is found to increase with decreasing Sc-CO2 activity. This size variation is discussed in light of recent theoretical developments that account for the effect of Sc-CO2 activity on PS−CO2 interfacial tension and chain stretching of the corona versus the core.
Scrap Tire Disposal Procedures

Abstract Many procedures and processes for the disposal of scrap tires are available. Because of the complexity of the whole disposal problem—e.g., collection logistics, availability and location o...
Relevance of PepT1 in the Intestinal Permeability and Oral Absorption of Cefadroxil

Purpose To determine the contribution of intestinal PepT1 on the permeability and oral absorption of the β-lactam antibiotic drug cefadroxil.
A fast rod photoreceptor signaling pathway in the mammalian retina

Rod photoreceptors were recently shown to contact 'Off' cone bipolar cells, providing an alternative pathway for rod signal flow in the mammalian retina. By recording from pairs of rods and Off cone bipolar cells in the ground squirrel (Spermophilus tridecemlineatus), we measured the synaptic responses of mammalian rods unfiltered by the slow kinetics of the rod bipolar cell response. We show that vesicle fusion and turnover in mammalian rods is fast, and that this new pathway can mediate rapid signaling.
Nitrogen and carbon flow from rock to water: Regulation through soil biogeochemical processes, Mokelumne River watershed, California, and Grand Valley, Colorado

[1] Soil denitrification is an ecologically important nitrogen removal mechanism that releases to the atmosphere the greenhouse gas N2O, an intermediate product from the reduction of NO3− to N2. In this study we evaluate the relationship between soil carbon and denitrification potential in watersheds with bedrock acting as a nonpoint source of nitrogen, testing the hypothesis that nitrate leaching to stream water is in part regulated by denitrification. Two sites, one in a Mediterranean climate and the other in an arid climate, were investigated to understand the interplay between carbon and denitrification potential. Both sites included carbonaceous bedrock with relatively high nitrogen concentrations (>1,000 mg N kg−1) and had low background nitrogen concentrations in surface and groundwater. There was a net accumulation of carbon and nitrogen in soil relative to the corresponding bedrock, with the exception of carbonaceous shale from the arid site. There the concentration of carbon in the soil (15,620 mg C kg−1) was less than the shale parent (22,460 mg C kg−1), consistent with the bedrock being a source of soil carbon. Rates of denitrification potential (0.5–83 μg N kg−1 hr−1) derived from laboratory incubations appeared to be related to the ratio of dissolved organic carbon and nitrate extracted from soils. These data indicate that microbial processes such as denitrification can help maintain background nitrogen concentrations to tens of μM N in relatively undisturbed ecosystems when nitrogen inputs from weathering bedrock are accompanied by sufficient organic carbon concentrations to promote microbial nitrogen transformations.
Tg and Tg breadth of poly(2,6-dimethyl-1,4-phenylene oxide)/polystyrene miscible polymer blends characterized by differential scanning calorimetry, ellipsometry, and fluorescence spectroscopy

Abstract The glass transition temperature ( T g ) behavior of bulk, miscible poly(2,6-dimethyl-1,4-phenyleneoxide)/polystyrene (PPO/PS) blends was studied by differential scanning calorimetry (DSC), ellipsometry, and fluorescence. Previous studies have shown that two underlying component T g s can be quantified by fluorescence in blends for which DSC fails to do so, either because the difference in homopolymers T g s is too small or one component is at trace levels. However, all methods show only a single glass transition in PPO/PS blends, indicating that the existence of two effective T g s due to self-concentration effects is not a universal phenomenon in miscible polymer blends with a large T g contrast. A T g -broadening effect is quantified in PPO/PS blends by both DSC and ellipsometry, but the glass transition breadth is relatively small, smaller even than for some homopolymers. The PPO/PS blends show a maximum T g breadth at ∼85 wt% PPO by DSC but at ∼50 wt% PPO by ellipsometry. Thus, the details of T g breadth for a multicomponent material can differ significantly between techniques, even when each technique evaluates T g breadth on a basis grounded in fundamental quantities (temperature dependence of heat capacity or of thermal expansivity). While fragility is useful in understanding perturbations to T g of well-dispersed, trace levels of one polymer by its blend partner in immiscible blends, fragility is not significantly correlated with T g perturbations in the form of T g breadth in strongly miscible PPO/PS blends with coupled dynamics, e.g., neat PPO has a high fragility relative to some blend compositions but a much smaller T g breadth.
A model for roll waves in gas-liquid flow

Abstract A liquid film flowing co-currently with a high speed gas flow often consists of a slow moving base film containing a sequence of flow surges or roll waves. Experiments have been conducted to determine the profiles of height, wall shear stress and gas pressure for individual roll waves. On the basis of these measurements a physical interpretation of roll waves is given and a mathematical model is developed. The average properties of the liquid film are given by summing the contributions from the roll waves and from the base film.
Axial mixing of particles in batch ball mills

Abstract An experimental study of the axial mixing of dry, powders in batch ball mills has been carried out. For a system of silicon carbide and garnet particles in a laboratory mill containing small plastic balls, the observed mixing is in good agreement with a simple diffusion model. Empirical expressions are presented which relate the diffusion coefficient to the ball and particle loading in the mill. The expressions seem to be valid over most of the practical range of operating conditions except when the filing of either particles or balls is very low. Under these conditions, segregation of balls and particles occurs, apparently leading to anomalous values of the diffusion coefficient.
Is it necrotizing enterocolitis, microcolon of prematurity, or delayed meconium plug? A dilemma in the tiny premature infant.

Abstract Failure of a small premature newborn to adequately evacuate meconium for days or weeks has been attributed to "probable necrotizing enterocolitis (NEC)" or "microcolon of prematurity." The authors present an unusual type of "meconium plug syndrome" with the same clinical picture, seen in tiny premature babies (500 to 1,500 g), which required a contrast enema or Gastrografin upper gastrointestinal (UGI) series to evacuate the plugs. The obstruction resolved. Twenty babies (480 to 1,500 g) presented with the same clinical picture without any x-ray suggestion of NEC; contrast enemas were performed because of the suspicion of meconium plug syndrome. All 20 had extensive meconium plugs that were evacuated by the enema or by a Gastrografin UGI series. Most of them improved after the plugs were passed. These infants differ from typical full-term babies with meconium plug syndrome in a number of ways: (1) many of the mothers were on magnesium sulfate (MgSO 4 ) or had eclampsia; (2) the plugs were diagnosed late rather than shortly after birth; and (3) the plugs were significant, extending to the right colon. The authors believe that when a tiny premature baby has findings consistent with meconium plug syndrome, the baby should be transported to radiology, for a Gastrografin enema, despite the difficulties involved. Delay postpones the start of feedings, and increses the number of radiographic studies.
Effect of mass perturbations on the LA mode of polymers: Surface bromination of polyethylene crystals

Abstract Bromine atoms have been attached to the surface of polyethylene single crystals and the effect of these surface masses on the longitudinal acoustic mode has been determined. As the amount of bromine is increased, the LA mode peak frequency decreases and the bandwidth increases. The observed peak frequency decrease is in good agreement with values calculated from the composite rod model.
Design of a piezoelectrically driven hydraulic amplification microvalve for high-pressure high-frequency applications

This paper reports the design of a piezoelectrically-driven microfabricated valve for high frequency control of large pressure fluid flows. The enabling concept of the valve is the ability to convert the small displacement of a piezoelectric element into a large valve cap stroke through the use of a hydraulic fluid, while maintaining high force capability. The current valve design, with operating frequency of 24 kHz and valve stroke of 40 micrometer, has been tailored for use in microhydraulic actuation and energy-harvesting devices, which require high-frequency regulation of approximately 1 ml/sec fluid flows across pressure differentials of 1-2 MPa.
Current status and future prospect of immersion lithography

Immersion lithography is rapidly approaching the manufacturing phase. A production-quality exposure tool system with NA=1.07 (Nikon NSR-S609B) was constructed to target the start of immersion lithography for IC manufacturing in 2006. Its projection optics have very small wavefront aberration and lowest local flare levels. The overlay issue has been analyzed, and its cause was found to be evaporation cooling. With the tandem stage and local fill nozzle implemented in the S609B, we have successfully avoided the evaporation cooling so that the good wet-to-dry mix-and-match overlay data have been obtained. The major part of immersion specific defects is caused by dried water-droplets, i.e. water-marks. The local fill nozzle has eliminated this defectivity by avoiding air flow in the nozzle. In the future, water immersion with NA=1.30 optics will be used for half-pitch 45nm manufacturing. Finer pattern imaging down to 32nm seems to need high-index material immersion or nonlinear double patterning, but these have several issues and concerns to be solved.
Dürer in French Letters

(1991). Durer in French Letters. Symposium: A Quarterly Journal in Modern Literatures: Vol. 45, No. 1, pp. 385-387.
Outcomes of Nurse Caring as Perceived by Individuals with Spinal Cord Injury During Rehabilitation

A study was undertaken to describe the meaning, process, and consequences of nurse caring from the perspective of persons with spinal cord injuries (SCI) during rehabilitation. The constant comparative method, or grounded theory, was used in this prospective, exploratory project. In-depth tape-recorded interviews were conducted with 22 participants throughout their initial rehabilitation stay. A process of knowledge acquisition and decision making, facilitated by nurses and therapists in special caring relationships with the persons with SCI, resulted in outcomes of well-being, self-care, autonomy in decision making, independence, and hope, all of which contributed to the persons with SCI's reintegration of self before their discharge from inpatient rehabilitation.
Correctness-preserving program transformations

This paper extends the predicate calculus formalization of the partial correctness properties of programs (Ki, Go) to include the preservation of correctness under program transformations. The general notion of "program transformations which preserve properties" is fundamental to the theory of programming and programming languages. In the context of proofs of program correctness, transformations which preserve correctness can be used to improve less efficient, but easier to prove, programs. The basic argument in the use of correctness-preserving program transformations (hereafter CPTs) is:Assume that G is a program (with attached assertions) which has been proved correct with respect to some input-output relation Ain-Aout. Now suppose that S is some part of G, e.g. an expression, assertion, statement, etc., which is to be replaced by some other such part S' to produce the program G'. The goal is to prove that G' is also correct with respect to Ain-Aout and therefore the replacement preserves overall program correctness. Moreover, if the replacement has only a local effect, e.g. the body of a loop, then the proof of correctness-preservation should be restricted to that part of the program affected by the replacement.Section 2 reviews the current paradigm for proving program correctness. An example in section 3 illustrates CPTs in a sequence of improvements on a correct and simple, but inefficient, initial program. In section 4, the formalization of partial correctness properties of programs is recast as a semantic language definition using Knuth's semantic method (Kn1). This formalization is then used in section 5 to describe the mechanics of performing CPTs. In section 6, several questions about the formalization of sections 4 and 5 are discussed and a generalization is proposed. Finally, section 7 returns to a concrete example and suggests that the most effective use of CPTs is by identification of schematic forms. Related work is mentioned in section 8.
Fabrication of titania and titania–silica aerogels using rapid supercritical extraction

Titania (TiO2) and titania–silica (TiSi) aerogels are suitable for photocatalytic oxidation of volatile organic compounds for pollution mitigation; however, methods for fabricating these aerogels can be complex. In this work we describe the use of a rapid supercritical extraction (RSCE) technique to prepare TiO2 and TiSi aerogels in as little as 8 h. The RSCE technique uses a metal mold and a four-step hydraulic hot press procedure to bring the solvents in the sol–gel pores to a supercritical state and control the supercritical fluid release process. Resulting TiO2 aerogels were powdery with BET surface areas of 130–180 m2/g, pore volumes ~0.5 cm3/g and skeletal densities of 3.6 g/mL. Monolithic TiSi aerogels were made using two different methods. An impregnation process, in which titania precursor was added to a silica sol–gel, took 4–8 days to complete with a 7-h RSCE and resulted in translucent aerogels with high surface area (560–650 m2/g) and pore volume (2.0–2.6 cm3/g), bulk densities ranging from 0.1 to 0.4 g/mL and skeletal densities of 2.3 g/mL. A co-precursor method for preparing TiSi aerogels took 8 h to complete. The precursor chemical mixture was poured directly into the mold and processed in a 7-h RSCE process. The resulting aerogels were opaque, with high surface areas (510–580 m2/g), low bulk density (0.03 g/mL), skeletal densities of 2 g/mL and pore volumes of 2.6–3.5 cm3/g. Preliminary solar simulator studies show that TiO2 and TiSi aerogels are capable of photocatalytic degradation of methylene blue in aqueous solution.
Fault detection in multi-core processors using chaotic maps

Exascale systems built using multi-core processors are expected to experience several component faults during code executions lasting for hours. It is important to detect faults in processor cores so that faulty cores can be removed from scheduler pools, nodes with high failures can be swapped out, applications can be migrated, and check-point recoveries can be initiated. We propose light-weight codes that utilize chaotic computations and customized threads to detect component faults in multi-core processors. They concurrently execute dedicated threads that implement Poincare and identity maps, which are customized to isolate faults in arithmetic operations, memory elements and interconnects. The instruction execution errors and local memory errors are detected by threads dedicated to processor cores, and errors in inter-processor crossconnects are detected by global-local memory movements. We present preliminary implementation results on 4- and 48-core HP workstations under simulated faults.
A Novel Topical Rapamycin Cream for the Treatment of Facial Angiofibromas in Tuberous Sclerosis Complex

Facial angiofibromas are dermatological manifestations of tuberous sclerosis complex, a neurocutaneous disorder characterized by excess cell growth and proliferation. Oral rapamycin has been used to treat visceral tuberous sclerosis-related tumors; however, the side effect profile of this medicine precludes its routine use in patients lacking significant internal involvement. The authors formulated a novel rapamycin cream that is easy to compound and apply, does not cause local or systemic side effects, and results in a dramatic improvement of facial angiofibromas.
Critical computer literacy: computers in first-year composition as topic and environment

Abstract Because of the persuasive and positive cultural discourse about technology, some first-year students—who are increasingly asked to develop their postsecondary literacy skills in a classroom that makes use of computers—are profoundly affected by and often find it difficult to resist these cultural messages. This in turn affects their ability to develop critical computer literacy, a skill and disposition scholars have stressed the importance of in recent years. By using the computer as both subject and medium, and using critical qualitative research techniques as method, this study addresses how first-year students understand their influence by cultural assumptions about technology. The computer played a central and dual role in this study—as both content and as means to foster critical computer literacy. This article presents three meaning perspectives on technology that students expressed based on formative experiences they have had with it. This article also presents revealing characteristic expressions in these identifiable student perspectives. The results suggest clear implications for how computers and composition scholars incorporate computer technology into our pedagogy if one of our goals is to help students develop critical computer literacy.
Part 2: Treatment of Snail Bait Toxicity in Dogs: retrospective Study of 56 Cases

Summary A retrospective study was done of 26 cases of metaldehyde and 30 cases of methiocarb toxicity in dogs. Physical signs and treatment protocols are described for four stages of toxicity: asymptomatic exposure; initial toxicity; convulsions; and post-convulsions. Diazepam-ketamine combination was used as the primaty anesthetic agent in all cases requiring general anesthesia, and proved effective. Metaldehyde cases required a significantly higher number of sedative and anesthetic doses (p < 0.001). Pentobarbitone was not used. There were no incidents of respiratory or cardiac arrest at the time of anesthesia induction. Emetics, gastric Iavage, and rectal enemas were productive in removing the molluscicide from the gastrointestinal tract. Ninety percent of the methiocarb patients and 69% of the metaldehyde patients were fit for discharge in 12 hours or less, though there was a wide variation. Both metaldehyde and methiocarb groups had a high survival rate, 100% and 93%, respectively.
Endo-β-N-acetylglucosaminidase-catalyzed polymerization of β-Glcp-(1→4)-GlcpNAc oxazoline: a revisit to enzymatic transglycosylation

An alternative synthesis of beta-Glcp-(1-->4)-GlcpNAc oxazoline is described, and its enzymatic reaction with the endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) was re-investigated. Under normal transglycosylation conditions with a catalytic amount of enzyme, Endo-A showed only marginal activity for transglycosylation with the disaccharide oxazoline, consistent with our previous observations. However, when used in a relatively large quantity, Endo-A could promote the transglycosylation of the disaccharide oxazoline to a GlcpNAc-Asn acceptor. In addition to the initial transglycosylation product, a series of large oligosaccharides were also formed due to the tandem transglycosylation to the terminal glucose residues in the intermediate products. In the absence of an external acceptor, Endo-A could polymerize the disaccharide oxazoline to form oligo- and polysaccharides having the -4-beta-(Glcp-(1-->4)-beta -GlcpNAc)-1-repeating units. This is the first example of an endo-beta-N-acetylglucosaminidase-promoted polymerization of activated oligosaccharide substrates. This enzymatic polymerization may find useful applications for the synthesis of novel artificial polysaccharides.