cssi/SciSciGPT-SciSciNet huggingface dataset:
Examination of membrane rupture as a mechanism for mammalian cell detachment from fibronectin-coated biomaterials.

Synthetic biomaterials intended for the reconstruction of tissues and organs must be capable of sustaining adhesive contact with adjacent cells and tissues under mechanical and hydrodynamic stresses. To facilitate this adhesion, extracellular matrix proteins or peptide sequences are frequently immobilized to the biomaterial interface. These ligands enhance cell attachment by raising the number of cell receptor/ligand interactions, but consequently they may alter the mechanism of cell detachment. In particular, as the cell membrane is more strongly immobilized to the substratum, the tendency for cell detachment to involve membrane rupture may increase. To test this hypothesis, cells were fluorescent stained with a membrane dye, allowed to attach to fibronectin-coated model substrates for 30 min, and then subjected to a spatially dependent range of shear stress for 5 min (28–220 dyn/cm2) using a radial-flow chamber. Phase-contrast and fluorescent images were analyzed to determine the probability for cell detachment and the area of fluorescent debris left by detaching cells as a function of fibronectin concentration, magnitude of shear stress, and time. It was found at all concentrations of fibronectin that the majority of detaching cells left membrane fragments, the mean size of these fragments was independent of shear stress, and the shape independent of the direction of flow. However, mean fragment area increased with concentration of fibronectin and decreased with duration of shearing flow. We postulate that the area of debris reflects the extent of cell attachment prior to the application of shear and that adhesive complexes can disassemble at the onset of flow. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 658–666, 2003
A generalization of the Lamé and somigliana stress functions for the dynamic linear theory of viscoelastic solids

Abstract Complete stress function solutions of the equations of dynamic linear viscoelasticity are obtained as generalizations of the Lame and Somigliana representations in elasto-dynamics. The generalized Lame stress functions satisfy hereditary wave equations, for which a particular solution is (formally) derived.
The Proactive Behavior of Younger Salespeople: Antecedents and Outcomes

The purpose of this study is to model and test some of the antecedents (individual characteristics) and outcomes (selling performance) of proactive behavior among younger salespeople. Using social cognitive theory agency perspective, we extend the existing proactive behavior literature into the sales domain. We sampled 278 industrial salespeople and tested a model to confirm that younger salespeople tend to engage in proactive behaviors when they are intrinsically motivated, confident in the tasks of selling, and willing to take risks. Proactive behavior, in turn, resulted in our salesperson sample demonstrating high levels of behavior performance and job involvement. Our findings may help sales channel managers begin to assess the potential role of proactive salespeople within their sales organization. Understanding that proactivity (both directly and indirectly) impacts selling performance, managers might specifically attempt to identify salesperson proactive behavior characteristics during the intervie...
Synergistic effects of prostacyclin analogs and phosphodiesterase inhibitors on cyclic adenosine 3',5' monophosphate accumulation and adenosine 3'5' triphosphate release from human erythrocytes.

Prostacyclin (PGI2) and phosphodiesterase 5 (PDE5) inhibitors are potent vasodilators that are used alone and in combination for the treatment of pulmonary arterial hypertension (PAH). Although these vasodilators are known to stimulate relaxation of vascular smooth muscle directly, other cells in circulation, including erythrocytes, express prostacyclin receptor (IPR) and contain PDE5. The binding of PGI2 analogs to the erythrocyte IPR results in activation of a signaling pathway that increases cyclic adenosine 3′,5′ monophosphate (cAMP), a requirement for adenosine 3′5′ triphosphate (ATP) release. Within this pathway, cAMP levels are regulated by phosphodiesterase 3 (PDE3), a PDE that is inhibited by cGMP, a cyclic nucleotide regulated by the activity of PDE5. Since inhibition of PDE3 enhances ATP release in response to PGI2 analogs, we investigated if the selective PDE5 inhibitors, zaprinast (ZAP) and tadalafil (TAD), would similarly increase cAMP and ATP release from human erythrocytes in response to t...
Meeting emission standards with high-sulfur coals

Abstract The economics of strategies for meeting sulfur oxides (SO x ) emission standards from furnaces fueled with high-sulfur coals has been assessed based on published data. The strategy of SO x control depends on how the coal is utilized. For large power plants, flue-gas desulfurization (FGD) is preferable to conversion of coal to clean fuel. In comparison with coal conversion, the total capital and operating costs for FGD are almost an order of magnitude lower, thermal efficiencies are higher, and utility requirements are lower. Even with possible breakthroughs in coal-conversion technologies, it appears that FGD will remain the economically preferred route to desulfurization. FGD has been in commercial operation since 1968, and the reliability of the process has reached an acceptable level. For industrial furnaces, direct combustion is preferred to gasification because gasification is inherently expensive. Fluidized-bed combustion is the only viable option for clean direct combustion of coal in small industrial furnaces. Fluidized-bed combustion has reached commercial status and is economically competitive in many parts of the world. For furnaces requiring gaseous or liquid fuels, gasification to medium-Btu gas is preferred. For domestic and commercial uses, coal can be gasified to clean, low-Btu gas. This is an old process and might be amenable to cost reduction through application of new technologies. The only other economically viable approach involves the production of clean solid fuel by compounding coal with additives such as limestone and manganese nodules.
Inactivation of creatine kinase by S-glutathionylation of the active-site cysteine residue

Protein S-thiolation, the formation of mixed disulphides of cysteine residues in proteins with low-molecular-mass thiols, occurs under conditions associated with oxidative stress and can lead to modification of protein function. In the present study, we examined the site of S-thiolation of the enzyme creatine kinase (CK), an important source of ATP in myocytes. Inactivation of this enzyme is thought to play a critical role in cardiac injury during oxidative stress, such as during reperfusion injury. Reaction of rabbit CK M isoenzyme with GSSG, used to model protein S-thiolation, was found to result in enzyme inactivation that could be reversed by GSH or dithiothreitol. Measurement of GSH that is released during the thiolation reaction indicated that the maximum extent of CK thiolation was approx. 1 mol of GSH/mol of protein, suggesting thiolation on one reactive cysteine residue. Accordingly, matrix-assisted laser-desorption ionization MS confirmed that the molecular mass of CK was increased, consistent with addition of one GSH molecule/molecule of CK. Using trypsin digestion, HPLC and MS analysis, the active-site cysteine residue (Cys(283)) was identified as the site of thiolation. Reversal of thiolation was shown to be rapid when GSH is abundant, rendering dethiolation of CK thermodynamically favoured within the cell. We conclude that S-glutathionylation of CK could be one mechanism to explain temporary reversible loss in activity of CK during ischaemic injury. The maintainance of GSH levels represents an important mechanism for regeneration of active CK from S-glutathionylated CK.
One-dimensional Schrödinger equation in the harmonic oscillator basis with various potentials☆

Abstract A FORTRAN 77 program has been written for computing the one-dimensional Schrodinger equation in the harmonic oscillator basis. It runs on the personal computer PC-486. Seven different kinds of vibrational operator functions have been considered. The program can be readily modified by users for different purposes. The polynomial potential function is discussed in much detail and comparisons have been made. Some test-run inputs and outputs have also been given.
The Cbp2 Protein Stimulates the Splicing of the ω Intron of Yeast Mitochondria

The Cbp2 protein is encoded in the nucleus and is required for the splicing of the terminal intron of the mitochondrial COB gene in Saccharomyces cerevisiae . Using a yeast strain that lacks this intron but contains a related group I intron in the precursor of the large ribosomal RNA, we have determined that Cbp2 protein is also required for the normal accumulation of 21S ribosomal RNA in vivo . Such strains bearing a deletion of the CBP2 gene adapt slowly to growth in glycerol/ethanol media implying a defect in derepression. At physiologic concentrations of magnesium, Cbp2 stimulates the splicing of the ribosomal RNA intron in vitro . Nevertheless, Cbp2 is not essential for splicing of this intron in mitochondria nor is it required in vitro at magnesium concentrations >5 mM. A similar intron exists in the large ribosomal RNA (LSU) gene of Saccharomyces douglasii . This intron does need Cbp2 for catalytic activity in physiologic magnesium. Similarities between the LSU introns and COB intron 5 suggest that Cbp2 may recognize conserved elements of the these two introns, and protein-induced UV crosslinks occur in similar sites in the substrate and catalytic domains of the RNA precursors.
Feeding capabilities and limitation of herbivorous molluscs: A functional group approach

The susceptibility of an alga to an herbivorous mollusc depends, in part, upon the size and toughness of the plant relative to the feeding ability of the mollusc. In this study, algae are subdivided into seven functional groups based on these and other physiological characteristics. Herbivorous prosobranchs and chitons are subdivided into four functional groups based on the structure of their feeding apparatus. Distinct patterns in the diets of these molluscs are evident when feeding data, based on these functional groups, are examined. Most herbivorous mollusc species eat algal forms that are either minute (i.e., micro- and filamentous algae) or very large and expansive (kelp-like or crustose algae). Algae of intermediate size (erect forms 1- to 10-cm tall) are eaten to a lesser extent, possibly because they are too large to be rasped from the substratum and too small for most herbivores to occupy. Herbivorous archaeogastropods (excluding limpets) and mesogastropods tend to eat filamentous and microscopic algal forms predominantly, whereas limpets and chitons feed on large, leathery and crustose algae. These dietary differences reflect functional differences in the feeding apparatus of these herbivore groups. Radulae of herbivorous mesogastropods function like rakes and can ingest larger, tougher algae than can radulae of nonlimpet archaeogastropods. The latter function more like brooms by sweeping the substratum broadly, but exerting little force. Limpets and chitons have superior excavating abilities because their radulae have: robust buccal muscles surrounding them, a reduced number of points of contact on the substratum, and minerally hardened teeth. The feeding apparatus of chitons is most versatile since it possesses features found in all herbivorous gastropod functional groups, and thus, it can sweep and excavate simultaneously. This functional group approach suggests various hypotheses concerning algal community structure, plant/herbivore and herbivore/herbivore interactions, the relative importance of structural defenses in algae, and the evolution of specialized grazers. These hypotheses are examined using data from published accounts.
Isobutyl 2‐cyanoacrylate as an osseous adhesive in the repair of osteochondral fractures

An in vivo evaluation of isobutyl 2-cyanoacrylate as an osseous adhesive was done in an effort to answer two questions: Used in limited amounts, can this monomer maintain the reduction of an unstable intra-articular osteochondral fracture while allowing for fracture healing around the sites of adhesive placement? Used in limited amounts, in this monomer toxic to adjacent viable bone? Osteochondral fractures were created in 32 dog knees. In 16 knees, the fracture reduction was secured with three small drops of adhesive placed around the periphery of the fracture surface. In 16 control knees no adhesive was used. Eighty-one percent of the fractures in the adhesive-treated group united compared to 56% of the control group. Although the difference in number of fractures that healed in the two groups is not definitely statistically significant and no conclusion was drawn as to effectiveness of the adhesive, osseous healing was noted to proceed around the sites of adhesive placement and the monomer appeared nontoxic to adjacent bone.
PROTEIN AGGREGATION IN INTACT AND DISRUPTED PEROXIDIZING ERYTHROCYTE MEMBRANES

The effects of molecular organization on the interaction of peroxidizing lipids with proteins were studied by using human red cell membranes. Intact and chloroform-disrupted membranes were oxidized. Disruption of membranes was achieved by treatment with chloroform and subsequent elimination of the solvent. Lipid oxidation rates and SDS-electrophoretic protein patterns in the two types of membranes were compared. Specific 3H-DIDS label of band 3 allowed the study of the role of intrinsic proteins in the aggregation process. Lipid oxidation rate is not greatly affected by chloroform disruption although disrupted membranes show a higher rate of protein aggregation. α-Tocopherol decreases lipid oxidation and protein aggregation rates. Band 3 protein dimers (188,000 M.W.) appear earlier than the higher molecular weight protein aggregates (400,000 M.W.). The results suggest that native membrane organization prevents protein damage upon lipid peroxidation.
THE REDUCTION OF RETINENE1 TO VITAMIN A1 IN VITRO

In the surviving vertebrate retina the retinene1 liberated by bleaching rhodopsin is converted quantitatively to vitamin A1. Recent chemical studies have indicated that in this process the aldehyde group of retinene1 is reduced to the primary alcohol group of vitamin A1 (Morton; Wald). Some time ago we brought this reaction into a cell-free brei prepared from cattle retinas. The retinas were frozen, desiccated, ground, and exhaustively extracted with petroleum ether; the resulting powder, stirred in neutral buffer solution and exposed to light, converted its retinene1 completely to vitamin A1. Some time ago also we observed that fresh rhodopsin solutions exhibit a special type of fading in darkness following exposure to light, which is absent from the same solutions after aging. We have confirmed Bliss's identification of this reaction as the conversion of retinene1 to vitamin A1. The system which reduces retinene1 is fractionated anatomically in the retinal rods. The outer segments of the rods, broken off from the underlying retinal tissue, are unable to convert their retinene1 to vitamin A1. In the presence of a water extract of crushed retina they do perform this conversion. On the other hand the retinal tissue from which a water extract was taken has lost this capacity. Such washed retinal tissue is reactivated by returning the washings to the solid material. The activating effect of retinal washings on isolated outer limbs or washed retina is duplicated by a boiled muscle juice. This in turn can be replaced by reduced cozymase (reduced coenzyme I; DPN-H2); or by a mixture of DPN and fructosediphosphate. The conversion of retinene1 to vitamin A1 is therefore a reduction in which two atoms of hydrogen are transferred to retinene1 from reduced cozymase. It is assumed that this reaction is catalyzed by an apoenzyme, retinene1 reductase, present in the rod outer limb. This process is coupled with a second system in the outer segment which reduces DPN, using hexosediphosphate or one of its derivatives as hydrogen donor. This action of DPN brings a member of the vitamin B complex, nicotinic acid amide, into an auxiliary position in the rhodopsin system. In the isolated retina or in vitro systems the reduction of retinene1 proceeds irreversibly. Yet this reduction must be balanced by an oxidative process elsewhere in the rhodopsin cycle, since through rhodopsin as intermediate vitamin A1 regenerates retinene1.
Molecular transporters for peptides: delivery of a cardioprotective ϵPKC agonist peptide into cells and intact ischemic heart using a transport system, R7

Abstract Background: Recently, we reported a novel oligoguanidine transporter system, polyarginine (R 7 ), which, when conjugated to spectroscopic probes (e.g., fluorescein) and drugs (e.g., cyclosporin A), results in highly water-soluble conjugates that rapidly enter cells and tissues. We report herein the preparation of the first R 7 peptide conjugates and a study of their cellular and organ uptake and functional activity. The octapeptide ψϵRACK was selected for this study as it is known to exhibit selective ϵ protein kinase C isozyme agonist activity and to reduce ischemia-induced damage in cardiomyocytes. However, ψϵRACK is not cell-permeable. Results: Here we show that an R 7 -ψϵRACK conjugate readily enters cardiomyocytes, significantly outperforming ψϵRACK conjugates of the transporters derived from HIV Tat and from Antennapedia. Moreover, R 7 -ψϵRACK conjugate reduced ischemic damage when delivered into intact hearts either prior to or after the ischemic insult. Conclusions: Our data suggest that R 7 converts a peptide lead into a potential therapeutic agent for the ischemic heart.
Comparison of single junction AlGaInP and GaInP solar cells grown by molecular beam epitaxy

We have investigated ∼2.0 eV (AlxGa1−x)0.51In0.49P and ∼1.9 eV Ga0.51In0.49P single junction solar cells grown on both on-axis and misoriented GaAs substrates by molecular beam epitaxy (MBE). Although lattice-matched (AlxGa1−x)0.51In0.49P solar cells are highly attractive for space and concentrator photovoltaics, there have been few reports on the MBE growth of such cells. In this work, we demonstrate open circuit voltages (Voc) ranging from 1.29 to 1.30 V for Ga0.51In0.49P cells, and 1.35–1.37 V for (AlxGa1−x)0.51In0.49P cells. Growth on misoriented substrates enabled the bandgap-voltage offset (Woc = Eg/q − Voc) of Ga0.51In0.49P cells to decrease from ∼575 mV to ∼565 mV, while that of (AlxGa1−x)0.51In0.49P cells remained nearly constant at 620 mV. The constant Woc as a function of substrate offcut for (AlxGa1−x)0.51In0.49P implies greater losses from non-radiative recombination compared with the Ga0.51In0.49P devices. In addition to larger Woc values, the (AlxGa1−x)0.51In0.49P cells exhibited significan...
A telecom-based temporal cloak

We demonstrate a new temporal cloak capable of hiding 46% of the entire time axis at a repetition rate of 12.7 GHz. Our results introduce temporal cloaking into the practical domain of secure optical communication.
Hierarchical linear modeling of FIM instrument growth curve characteristics after spinal cord injury.

Abstract Warschausky S, Kay JB, Kewman DG. Hierarchical linear modeling of FIM instrument growth curve characteristics after spinal cord injury. Arch Phys Med Rehabil 2001;82:329-34. Objective: To examine the recovery of aspects of functional independence as a continuous process using growth curve analysis. Design: Retrospective database review of functional outcome assessment data from inception cohort. Setting: Inpatient rehabilitation unit; community. Patients: A total of 142 subjects (79.6% men; age range, 18-77yr; mean age ± standard deviation, 36.2 ± 15.5yr) who were admitted to a rehabilitation unit between March 1986 and November 1994 with a minimum of 4 postinjury FIM™ assessments. Neurologic subgroups included 63 individuals with paraplegia, 36 with low tetraplegia, 24 with high tetraplegia, and 19 with incomplete injury. Main Outcome Measure: FIM instrument. Results: Growth curve analyses with hierarchial linear modeling using a decelerating recovery function yielded a reliable model in which longer rehabilitation length of stay was associated with a more rapid rate of recovery but lower plateau. Neurologic injury category had expected effects on rate and degree of recovery. Level of impairment-specific results included an age effect in which older age was associated with lower level of plateau. In specific neurologic groups there was a significant gender effect, in which men made more rapid recovery than women, and a significant effect of level of education, in which higher education was associated with more rapid rate of recovery. Rate of FIM recovery was reliably modeled in the sample with incomplete injuries, but none of the demographic predictors was significant. Conclusions: Functional recovery can be modeled as a decelerating rather than simple linear function. The study of predictors of recovery characteristics, including rate of recovery and plateau, offers a valuable way of understanding rehabilitative needs and outcomes. Gender and education effects on the recovery process are intriguing and warrant further investigation.
Student Opinions regarding the Mandatory Use and Ownership of Personal Computers.

Several institutions of higher education recently have adopted policies requiring students to take computer courses and/or own personal computers. Typically, these decisions have been made by faculty and administrators without input from students. The purpose of this study was to analyze student opinion regarding such policies. To this end, the Student Affairs Research and Evaluation Office at the University of Massachusetts at Amherst conducted a telephone survey of a random sample of 308 undergraduates. The results show that students generally favor mandatory computer instruction but not mandatory computer ownership. Subsequent regression analyses of these data indicate that whether or not computer proficiency is seen as a salient skill for future employment is a key explanatory variable that determines support for either computer policy.
Economic impacts of marine reserves: the importance of spatial behavior

Abstract Marine biologists have shown virtually unqualified support for managing fisheries with marine reserves, signifying a new resource management paradigm that recognizes the importance of spatial processes in exploited systems. Most modeling of reserves employs simplifying assumptions about the behavior of fishermen in response to spatial closures. We show that a realistic depiction of fishermen behavior dramatically alters the conclusions about reserves. We develop, estimate, and calibrate an integrated bioeconomic model of the sea urchin fishery in northern California and use it to simulate reserve policies. Our behavioral model shows how economic incentives determine both participation and location choices of fishermen. We compare simulations with behavioral response to biological modeling that presumes that effort is spatially uniform and unresponsive to economic incentives. We demonstrate that optimistic conclusions about reserves may be an artifact of simplifying assumptions that ignore economic behavior.
Systemic Inflammatory Markers and Aspiration Cell Count May Not Differentiate Bacterial From Fungal Prosthetic Infections

Background Fungal periprosthetic joint infections (PJIs) are rare. Fewer than 200 cases have been reported in the literature. The characteristics of systemic inflammatory markers and joint aspirate cell count analysis obtained in patients with fungal PJIs have not been fully assessed. The ability to diagnose involvement of fungal PJI preoperatively may optimize the surgical and medical management of these patients.
Inheritance of Lysosomal Acid β -Galactosidase Activity and Gangliosides in Crosses of DBA/2J and Knockout Mice

GM1 gangliosidosis is a progressive neurodegenerative disease caused by deficiencies in lysosomal acid β-galactosidase (β-gal) and involves accumulation and storage of ganglioside GM1 and its asialo form (GA1) in brain and visceral tissues. Similar to the infantile/juvenile human disease forms, B6/129Sv β-gal knockout (ko) mice express residual tissue β-gal activity and significant elevations of brain GM1, GA1, and total gangliosides. Previous studies suggested that inbred DBA/2J (D2) mice may model a mild form of the human disease since total brain ganglioside and GM1 concentration is higher while β-gal specific activity is lower (by 70–80%) in D2 mice than in inbred C57BL/6J (B6) mice and other mouse strains. A developmental genetic analysis was conducted to determine if the genes encoding β-gal (Bgl) in the D2 and the ko mice were functionally allelic and if the reduced brain β-gal activity in D2 mice could account for elevations in total brain gangliosides and GM1. Crosses were made between D2 mice homozygous for the Bgld allele (d/d), and either B6/129Sv mice heterozygous for the Bgl+ allele (+/−) or homozygous for the ko Bgl− allele (−/−) to generate d−/+ and d−/− mice. Specific β-gal activity (nmol/mg protein/h) showed additive inheritance in brain, liver, and kidney at juvenile (21 days) and adult (255 days) ages with the d−/− mice having only about 16% of the β-gal activity as that in the +/+ mice. These results indicate that the Bgl genes in the D2 and the ko mice are noncomplementing functional alleles. However, the d−/− mice did not express GA1 and had total brain ganglioside and GM1 concentrations similar to those in the d−/+ and +/+ mice. These results suggest that the reduced brain β-gal activity alone cannot account for the elevation of total brain gangliosides and GM1 in the D2 mice.
Apical and basolateral Na+/H+ exchange in the rabbit outer medullary thin descending limb of Henle: role in intracellular pH regulation.

The present study was designed to investigate the apical and basolateral transport processes responsible for intracellular pH regulation in the thin descending limb of Henle. Rabbit thin descending limbs of long-loop nephrons were perfused in vitro and intracellular pH (pH i ) was measured using BCECF. Steady-state pH i in HEPES buffered solutions (pH 7.4) was 7.18±0.03. Following the removal of luminal Na+, pH i decreased at a rate of 1.96±0.37 pH/min. In the presence of luminal amiloride (1mm), the rate of decrease of pH i was significantly less, 0.73±0.18 pH/min. Steady-state pH i decreased 0.18 pH units following the addition of amiloride (1mm) to the lumen (Na+ 140mm lumen and bath). When Na+ was removed from the basolateral side of the tubule, pH i decreased at a rate of 0.49±0.05 pH/min. The rate of decrease of pH i was significantly less in the presence of 1mm basolateral amiloride, 0.29±0.04 pH/min. Addition of 1mm amiloride to the basolateral side (Na+ 140mm lumen and bath) caused steady-state pH i to decrease significantly by 0.06 pH units. When pH i was acutely decreased to 5.87±0.02 following NH4Cl removal (lumen, bath), pH i failed to recover in the absence of Na+ (lumen, bath). Addition of 140mm Na+ to the lumen caused pH i to recover at a rate of 2.17±0.59 pH/min. The rate of pH i recovery was inhibited 93% by 1mm luminal amiloride. When 140mm Na+ was added to the basolateral side, pH i recovered only partially at 0.38±0.07 pH/min. Addition of 1mm basolateral amiloride inhibited the recovery of pH i , by 97%. The results demonstrate that the rabbit thin descending limb of long-loop nephrons possesses apical and basolateral Na+/N+ antiporters. In the steady state, the rate of Na+-dependent H+ flux across the apical antiporter exceeds the rate of Na+-dependent H+ flux via the basolateral antiporter. Recovery of pH i following acute intracellular acidification is Na+ dependent and mediated primarily by the luminal antiporter.
The Prevention of Pneumococcal Disease by Vaccines: Promises and Challenges

This article reviews the epidemiology of pneumococcal disease and the current data on pneumococcal vaccine efficacy, discusses promising new data regarding development of new protein-conjugate pneumococcal vaccines, and addresses controversies surrounding the widespread population use of these vaccines. Armed with these data, physicians, nurses, third party payers, and health care systems should develop systems and eliminate unintentional barriers so as to achieve widespread use of these life-saving vaccines. As history has demonstrated to us, control of pneumococcal disease is highly unlikely to occur from heavy investments in newer and ever more expensive antibiotics, as opposed to better methods of preventing disease through the rational and widespread population use of vaccines.
Accumulation of metals in consumers associated with chromated copper arsenate-treated wood panels

Abstract Metals leached from chromated copper arsenate (CCA)-treated wood, taken up by epibiota and trophically transferred to their motile consumers or taken up directly by the consumers, were measured in caged organisms exposed to treated and untreated wood panels for 3 months. Epibiota on treated panels had more copper and arsenic than epibiota on untreated panels, and amphipods living on the former had elevated copper. However, metal concentrations in grass shrimp (Palaemonetes pugio) and two teleost fish, the naked goby (Gobiosoma bosci) and mummichog (Fundulus heteroclitus), were unaffected by CCA-treated wood exposure. In addition, there was no evidence of biomagnification in the consumers other than the amphipods. Thus, trophic transfer was not demonstrated to the consumers, suggesting that the treated wood was not presenting a hazard to higher trophic levels. Fish may have more efficient mechanisms for regulating metal levels in their tissues. ©
Role of the complement system in pulmonary disorders

Immune injury in the lung is classically divided into types I-IV hypersensitivity, with the complement system being involved in types II and III hypersensitivity. Anaphylaxis and asthma are generally considered prototypes of type I hypersensitivity and hypersensitivity pneumonitis as an example of type III hypersensitivity in the lung. However, in asthma, for example, increasing evidence indicates that in addition to mast cells, T lymphocytes play an important role. Therefore, considering asthma as strictly a type I mediated reaction is too simplistic. This report will review the evidence regarding the involvement of the complement system and complement activation products in anaphylaxis, asthma and immune complex disease in various experimental models of pulmonary disease. Identification of the mediators responsible for the symptoms may suggest rational targets for the continued development of effective therapy to combat immune injury in the lung.
Root hairs, trichomes and the evolution of duplicate genes

The MYB-class proteins WEREWOLF and GLABRA1 are functionally interchangeable, even though one is normally expressed solely in roots and the other only in shoots. This shows that their different functions are the result of the modification of cis-regulatory sequences over evolutionary time. The two genes thus provide an example of morphological diversification created by gene duplication and changes in regulation.
Contrasting tectono-stratigraphy and structure in the Coast Belt near Chilko Lake, British Columbia: unrelated terranes or an arc – back-arc transect?

Stratigraphy and structural styles vary greatly in two areas of the Coast Belt near Chilko Lake (Chilcotin Ranges in the east and Coast Mountains in the west). No definite continuity between the two belts has been established in the pre-mid-Cretaceous geology, but this area may be a long-lived, episodic magmatic arc and nearby arc-related basin. The stratigraphic contrasts may reflect inherent differences between an arc and related basinal sequence. Triassic volcanic-arc sequences are part of the Stikine (western belt) and Cadwallader (eastern belt) terranes, which may be part of the same arc. The Jurassic is represented by one dated pluton in the west compared with almost continuous deposition of volcanogenic clastic rocks in the east. Lower Cretaceous sequences in the west and east may represent a volcanic arc and back-arc basin. The Taylor Creek Group (Albian) is the first definitive link between the two belts and represents an arc and intra-arc or back-arc basin. The structural evolution of the two be...
Cost effectiveness of ambulatory uterine activity monitoring

A cost analysis is presented comparing 34 patients who received uterine activity monitoring versus 33 patients who attempted to detect uterine activity by palpation. All patients were at high risk for preterm delivery and were given the same educational information and prenatal care regarding signs and symptoms of preterm labor. The results revealed an increase in newborn days (640) and cost to those patients who were in the self-palpation group ($13,364) compared to monitored parturients (268 days and $8,633). The difference was attributed to neonatal morbidity from an increased number of preterm deliveries greater than 26 weeks but less than 37 weeks (P = 0.04). The increase in NICU days was significant (P = 0.03). No difference in normal newborn costs for infants delivered after greater than 33 weeks could be detected between the two groups, but morbidity was increased among control infants delivering between 34 and 36 weeks. Uterine activity monitoring to prevent preterm birth appears to be medically effective and reduces cost.
Changes in the association of actin-binding proteins with the actin cytoskeleton during chemotactic stimulation of Dictyostelium discoideum

Triton-insoluble cytoskeletons were isolated from Dictyostelium discoideum AX3 cells prior to and following stimulation with 2'deoxy cyclic adenosine monophosphate (cAMP). Temporal changes in the content of actin and a 120,000 dalton actin-binding protein (ABP-120) in cytoskeletons following stimulation were monitored. Both actin and ABP-120 were incorporated into the cytoskeleton at 30-40 seconds following stimulation, which is cotemporal with the onset of pseudopod extension during stimulation of amoebae with chemoattractants. Changes in the content of total cytoskeletal protein and cytoskeletal myosin were determined under the same experimental conditions as controls. These proteins exhibited different kinetics from those of cytoskeletal ABP-120 and actin following the addition of 2'deoxy cAMP. The authors concluded that the association of ABP-120 with the cytoskeleton is regulated during cAMP signalling. Furthermore, these results indicate that ABP-120 is involved in cross-linking newly assembled actin filaments into the cytoskeleton during chemoattractant-stimulated pseudopod extension.
Multidimensional optimization of a stochastic model for X-ray diffraction from superlattices

Abstract We have developed a stochastic model to perform structural refinement of superlattices from X-ray diffraction. A minimal number of assumptions are made in our model and the stochasticity is introduced in the representation of the structure of the superlattices. The average and deviations from the average structural parameters of the superlattices were optimized by means of a multidimensional optimization process. The complete structural characterization of the superlattices has been therefore automated, fostering both theoretical and experimental advances in the area.
Marketing Debates: In the Classroom and Online

This paper recognizes the ongoing challenges that educators face in engaging students in classroom or online discussions and in developing their interest in the material that we want them to learn. The author suggests use of structured debates to add more variety to the teaching methods used in marketing courses and to help students learn and retain information. Debates fully engage the students, help them develop interpersonal and communication skills, encourage critical thinking, and lead to high levels of learning and retention of content. The author gives examples of structured debates successfully used in the classroom and in online courses and outlines procedures for implementing them.
The Spectral Irradiance of the Moon

Images of the Moon at 32 wavelengths from 350 to 2450 nm have been obtained from a dedicated observatory during the bright half of each month over a period of several years. The ultimate goal is to develop a spectral radiance model of the Moon with an angular resolution and radiometric accuracy appropriate for calibration of Earth-orbiting spacecraft. An empirical model of irradiance has been developed that treats phase and libration explicitly, with absolute scale founded on the spectra of the star Vega and returned Apollo samples. A selected set of 190 standard stars are observed regularly to provide nightly extinction correction and long-term calibration of the observations. The extinction model is wavelength-coupled and based on the absorption coefficients of a number of gases and aerosols. The empirical irradiance model has the same form at each wavelength, with 18 coefficients, eight of which are constant across wavelength, for a total of 328 coefficients. Over 1000 lunar observations are fitted at each wavelength; the average residual is less than 1%. The irradiance model is actively being used in lunar calibration of several spacecraft instruments and can track sensor response changes at the 0.1% level.
Energy-momentum sum rule and the anomalous behavior of the structure functions of nuclear targets.

We show that the data of Aubert et al. on the structure function of iron is in apparent violation of the energy-momentum sum rule. The systematics of the finite-q/sup 2/ corrections, when compared to data of Arnold et al., are an important ingredient to the argument. The discrepancy can be removed by an approximately 5% renormalization of the data of Aubert et al.
Chasing the dragon: the cultural metamorphosis of opium in the United States, 1825-1935.

Many things to many people, opium has played a role in the emergence of several power bases in the United States. In turn, these bases of power have shaped what opium is for the rest of us. Allopathic medicine brought opium and its derivatives under its control around the turn of the century, promulgating "addiction theory" and addiction clinics as part of its rise to preeminence among rival forms of medicine. Opium also played a role in the U.S.'s international economic and imperialistic ascendance. When politicians began to deploy a new discourse on opium early in this century, they were able to appropriate medical rhetoric. As the politics of opium heated up, some doctors were able to exploit the emerging politically inspired discourse to generate a subtly different medical knowledge of opiates and addiction while establishing a new subdiscipline with the political support of lawmakers and state institutions.
Can light absorption and photostability data be used to assess the photosafety risks in patients for a new drug molecule

Photosafety assessments are recommended for all new drug candidates intended for clinical use. In 2002, Testing guidances were issued by the regulatory authorities in the USA (2003) and Europe (2002). A key requirement is to measure the absorption of UV-visible light by a compound in the 290-700 nm range and to assess photostability. Further photosafety evaluation is recommended for molecules which absorb light energy in this region and may be unstable in light. Consequently, the current guidances do not specify what constitutes a significant level of light absorbance or photoinstability. The current study was undertaken to determine the level of light absorption by measuring the molar extinction coefficients (MEC) of a wide range of compounds reported in the literature to have known photosafety issues in humans. The results have shown that all compounds tested have absorbance intensities significantly above an MEC threshold of 1000 L mol(-1)cm(-1) and also display a wide range of photoinstability. The measurement of light absorption is a contributing part of an overall pre-clinical photosafety risk assessment process, whereas photostability assessments have proven to have limited value. Molecules with an MEC less than 1000 L mol(-1)cm(-1)are deemed less of a photosafety risk since this low level of light absorption is unlikely to prove harmful.
The enumerability and invariance of complexity classes

Several properties of complexity classes and sets associated with them are studied. An open problem, the enumerability of complexity classes, is settled by exhibition of a measure with some nonenumerable classes. Classes for natural measures are found to occupy the same isomorphism type; and a criterion for measures comes from this finding. General results about measures and unsolvability are presented and constraints are placed on complexity classes so that they possess identical properties.
Optimal acquisition techniques for digital breast tomosynthesis screening

A second-generation digital breast tomosynthesis system is used for a screening study comparing tomosynthesis with conventional two-view mammography with matched x-ray dose. The system acquires 15 projections of a breast at different angles using a digital detector. This work explores acquisition techniques that optimize the quality of projection images at low x-ray exposure. The system provides three target-filter combinations (Mo-Mo, Mo-Rh and Rh-Rh) and the recommended tube voltage range is from 25 to 40kVp. A thin disk was put on top of slabs of breast tissue equivalent materials (20 to 85mm). Contrast-to-noise ratio of the disk was measured from projections acquired with different kVp and target-filter combinations. The squared CNR normalized by average glandular dose was used to compare the quality/dose efficiency of different techniques. The optimal quality/dose efficiency was achieved as the detector entrance exposure was in the range of 5-30mR. Within this range, Mo-Mo gives the highest quality for 20mm; results are very close for 30mm; Rh-Rh is slightly better for 45mm and apparently better than others for 65 and 85mm. However, sufficient detector entrance exposure cannot be guaranteed for all cases due to the total dose limit and the system limit. For some cases, the detector is operated slightly off its optimal performance range. The kVp does not show an impact except for 85 mm, in which the quality/dose efficiency slightly increases at higher kVp. Rh-Rh is selected for > 40mm thickness; Mo-Mo is selected for 20mm thickness; and Mo-Rh is selected for 30 and 40mm.
Functional rehabilitation after cardiac valve surgery.

Abstract Functional rehabilitation after cardiac valve surgery was evaluated in a series of 267 patients operated upon during the years 1963 through 1970. All but a few were in N.Y.H.A. Functional Class III or IV prior to operation. Hospital mortality was 14%, and the late mortality was 26%. During the last four years (1967–1970), when only current-model Starr-Edwards valves were used, hospital mortality was reduced to 8% (5.4% for single- or double-valve replacement), but late mortality (15% within two years) was unchanged. The reduction in hospital mortality was due to improvements in surgical technique and postoperative care rather than to improved valve design. Although more than 70% of the survivors were in Functional Class I or II postoperatively, fewer than 20% returned to work and only 24% were asymptomatic. These findings did not improve during 1967–1970. Multivariable computer analysis failed to reveal specific preoperative factors that correlated with late mortality or functional results. Isolated mitral stenosis was associated with the lowest late mortality, and isolated mitral regurgitation had the highest late mortality. Long-standing congestive heart failure also carried a poor prognosis. Complications related to the prosthetic valve were reduced with current-model prostheses, but valve-related causes accounted for less than 12% of deaths, and late mortality due to progressive cardiac disease was unchanged. It is suggested that correction of cardiac valve lesions is performed too late in the course of the disease to significantly influence rehabilitation of most patients.
Cell wall characteristics and firmness of fresh pack cucumber pickles affected by pasteurization and calcium chloride.

Changes in cell wall pectic substances, degree of pectin methylation, bound Ca++, neutral sugar composition, and firmness were determined in mesocarp tissue of pasteurized and nonpasteurized fresh pack cucumber pickles. Large changes in solubility characteristics of pectic substances occurred in cell walls of nonpasteurized pickles that were attenuated by pasteurization. In particular, water and alkali soluble pectins declined, and nonextractable pectins increased during the first month of storage. The major changes in pectic substance solubility appeared to be related to reductions in the degree of pectin methylation with a minor influence of CaCl2. Galactose in cell walls of nonpasteurized pickles was substantially reduced, and the reduction in galactose was hindered by CaCl2 or pasteurization. The amount of bound Ca++ appeared to be associated with tissue firmness after one month in storage, since firmer tissue had more cell wall bound Ca++. While firmness was associated with the amount of bound Ca++, the amount of bound Ca++ was dependent on the supply of Ca++ and the degree of pectin methylation.
Automated staging of sleep in cats using neural networks.

Abstract Manual staging of sleep based on visual EEG criteria is a laborious and time-consuming task. In an effort to automate sleep staging, we have developed a neural network that ‘learns’ to stage sleep on the basis of wave band count data alone, in the cat. Wave band count data are collected on a microcomputer, using period-amplitude analysis. Delta waves, spindle bursts, ponto-geniculo-occipital (PGO) waves, electro-oculogram (EOG), basal electromyogram (EMG) amplitude, and movement artifact amplitude are collected, and used to ‘train’ the network to score sleep. These wave count data serve as the imput patterns to the net, and the corresponding manually scored sleep stages serve as a ‘teacher.’ We demonstrate that, when used to score the states of wake, slow wave sleep (SWS), desynchronized sleep (D), and the transition period from SWS to D (SP), these neural networks agree with manual scoring an average of 93.3% for all epochs scored. Neural network programs can learn both rules and exceptions, and since the nets teach themselves these rules automatically, a minimum of human effort is required. Because programming requirements are small for neural nets, this approach is readily adaptable to microcomputer-based systems and is widely applicable to both animal and human EEG analyses. The utility of this approach for the detection and classification of a variety of clinical neurophysiological disorders is discussed.
Combined Revascularization and Microvascular Free Tissue Transfer for Limb Salvage: A Six-Year Experience

for a mean duration of 7.4 months preoperatively and 12 patients had exposed bone or tendon. Vascular reconstruction included popliteal (3), tibial (6), and pedal (6) bypass with concomitant myocutaneous free flap, using mostly rectus abdominis or latissimus dorsi muscle. There were no perioperative deaths. One patient suffered a nonfatal myocardial infarction. Two patients had a postoperative wound hematoma and one required vascular graft revision. Patients were followed for 4 to 75 months (mean = 23 months). Four patients have required amputations (3 early, 1 late), three of whom had preoperative renal failure. The limb salvage rate has been 72% at 36 months, with 10 of 11 patients having functional ambulation. Combined revascularization and free tissue transfer is safe and durable, and long-term limb salvage is obtainable. Patients with renal failure had poorer outcomes in this series.