cssi/SciSciGPT-SciSciNet huggingface dataset:
A new approach to rank one linear algebraic groups

Abstract One can develop the basic structure theory of linear algebraic groups (the root system, Bruhat decomposition, etc.) in a way that bypasses several major steps of the standard development, including the self-normalizing property of Borel subgroups.
Techniomega production in pp colliders

We compute the cross section for techniomega production in pp colliders at \ensuremath{\surd}s =17 and 40 TeV via a gauge-boson-fusion process analogous to the \ensuremath{\pi}\ensuremath{\pi}\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\omega} process in QCD. Prospects for the detection of this resonance are discussed.
Differences between CNBr peptides of soluble and insoluble bovine collagens.

Abstract The compositions of the cyanogen bromide peptides of insoluble bovine skin and dentin collagens are nearly identical with those obtained from the soluble collagen. However, some qualitative and quantitative differences are present. The insoluble collagens do not go completely in solution after the treatment. The insoluble residues have compositions showing a firm association of collagen with non-collagenous peptides. The content of peptide α1-CB6 is sharply reduced in both insoluble skin and dentin collagen, indicating involvement of this peptide in the formation of intermolecular cross-links. Several heterogeneities were noted regarding many peptides. In particular, two forms of α1-CB3 and of α1-CB6 were isolated in agreement with the idea that two types of α1-chains are present. The situation is more complex, in that the second form of α1-CB3 from skin and dentin are not identical.
Insulating behavior of alkali-metal-covered GaAs(110)

A combined effort of local density approximation (LDA) and many-body calculations is aimed at an understanding of the nature of the insulating behavior of GaAs(110) under submonolayer alkali-metal coverage. In particular, a Hubbard model is constructed with its parameters extracted from LDA pseudopotential calculations. The electron hopping spectrum is calculated using an exact diagonalization technique. The combined LDA and many-body results demonstrate that the GaAs(110) under submonolayer alkali-metal coverage up to {theta}=0.25 is a Mott-Hubbard insulator. {copyright} {ital 1996 The American Physical Society.}
Factors Affecting the Design and Development of a Personal Learning Environment: Research on Super-users

After speculation in literature about the nature of Personal Learning Environments, research in the design and development of PLEs is now in progress. This paper reports on the first phase of the authors' research on PLE, the identification process of what potential users would consider important components, applications, and tools in a PLE. The methodology included surveying "super-users" on their use of existing tools, applications and systems and their preferences in learning, in order to enhance the development of a PLE and reach a specification that potential learners will find useful and empowering in their learning. The research resulted in suggestions on factors affecting technology use and uptake, human factors and attitudes, and interface design that need to be factored in the design and development of a PLE.
Leydig cell function in Klinefelter's syndrome

Abstract The two major secretion products of the normal testes were measured in peripheral plasma of eight patients with Klinefelter's syndrome; two agonadal, one castrate, one patient with isolated gonadotropin deficiency, and one patient with unclassified primary hypogonadism. Plasma testosterone and 17-α-hydroxyprogesterone were very low in all but the Klinefelter's patients. Testosterone values markedly varied, but were generally subnormal in Klinefelter's, ranging from 25–425 mμg 100 ml , 187 ± 160. The 17-α-hydroxyprogesterone (17-OHP), however, was elevated in three and within the normal range in five [Klinefelter's 120 ± 63 (SD) vs. normal 97 ± 21 (SD) m μg 100 ml , respectively]. The 17-OHP values are inappropriate when considered with the subnormal testosterone values. One of the youngest patients studied had a subnormal testosterone but a plasma 17-OHP that was three times the mean for a normal adult male. The 17-OHP in Klinefelter's was of testicular origin, since dexamethasone had minimal effect, but testosterone almost completely reduced plasma 17-OHP. The marked circadian variation of 17-OHP in normal males was not present in Klinefelter's, although noncyclic fluctuations were observed. LH in the form of chorionic gonadotropin produced a variable response. Some of the patients exhibited a rise in plasma 17-OHP and testosterone despite already elevated 17-OHP levels. The studies indicate the presence of a disorder involving Leydig cell steroidogenesis in Klinefelter's syndrome.
The hydrodynamics of DNA electrophoretic stretch and relaxation in a polymer solution.

Abstract Theories of DNA electrophoretic separations generally treat the DNA as a free draining polymer moving in an electric field at a rate that depends on the effective charge density of the molecule. Separations can occur in sieving media ranging from ultradilute polymer solutions to tightly cross-linked gels. It has recently been shown that DNA is not free-draining when both electric and nonelectric forces simultaneously act on the molecule, as occurs when DNA collides with a polymer during electrophoretic separations. Here we show that a semidilute polymer solution screens the hydrodynamic interaction that results from the application of these forces. Fluorescently labeled DNA tethered at one end in a semidilute solution of hydroxyl-ethyl cellulose stretch more in an electric field than they stretch in free solution, and approach free-draining behavior. The steady stretching behavior is predicted without adjustable parameters by a theory developed by Stigter using a hydrodynamic screening length found from effective medium theory. Data on the relaxation of stretched molecules after the electric field is removed agree with the Rouse model prediction, which neglects hydrodynamic interactions. The slowest relaxation time constant, τ R , scales with chain length as τ R ∼ L 1.9±0.17 when analyzed by the data collapse method, and as τ R ∼ L 2.17±0.17 when analyzed by multiexponential fit.
The effect of a response requirement on schedule-induced aggression

The attack behavior induced in pigeons by a fixed-ratio schedule of food reinforcement was compared with that induced by a variable-time schedule composed of the actual interreinforcement intervals of the preceding fixed-ratio schedule condition. For two of the four pigeons that exhibited schedule-induced aggression against a nearby stuffed pigeon, the response-dependent (fixed-ratio) schedule induced a higher rate of attack than did the response-independent (variable-time) schedule. For the remaining two birds, no measure of induced aggression was consistently related to either schedule condition. These results indicate that a response requirement for reinforcement is not a limiting condition for the induction of attack behavior in pigeons.
The effect of cultural orientation on the service timing preferences of customers in casual dining operations: An exploratory study

Abstract Sociological studies indicate that individuals’ orientations toward time are grounded in cultural tradition. This study employs samples from the USA and Hong Kong to identify if and how these differences impact service delivery expectations for casual restaurant dining. Results provide useful information for the modification of service practices to more closely align with the preferences of diverse consumer segments in the global market place.
Data structures to vectorize CG algorithms for general sparsity patterns

We describe an implementation of Conjugate Gradient-type iterative algorithms for problems with general sparsity patterns on a vector processor with a hierarchy of memories, such as the IBM 3090/VF. The implementation relies on the wavefront approach to vectorize the solution of the two sparse triangular systems that arise when using ILU type preconditioners. The data structure is the key to an effective implementation of sparse computational kernels on a vector processor. A data structure is a combination of a layout of the matrix coefficients and ordering schemes for the vectors to increase data locality. With the data structure we describe, we achieve comparable performance on both the matrix-vector product and the solution of the sparse triangular systems on a variety of real problems, such as those arising from large scale reservoir simulation or structural analysis.
Real-time measurement of anchorage-dependent cell adhesion using a quartz crystal microbalance

An in situ technique based on the mass-sensitive piezoelectric quartz crystal microbalance (QCM) was applied to continuously monitor the attachment and detachment of anchorage-dependent mammalian cells on a metal surface. Specifically, we have demonstrated that the attachment of Vero cells to metal surfaces on the piezoelectrically active area of the QCM results in decreases in the QCM resonant frequency that can be monitored conveniently in real time. Lysis and detachment of Vero cells caused by vesicular stomatitis virus (VSV) infection can also be monitored readily. Our results demonstrate that the QCM is a viable technique for monitoring anchorage-dependent cell attachment and detachment on surfaces (caused by stimulatory, inhibitory, or cytopathic effects).
The efficiency of logistic regression compared to normal discriminant analysis under class-conditional classification noise

In many real world classification problems, class-conditional classification noise (CCC-Noise) frequently deteriorates the performance of a classifier that is naively built by ignoring it. In this paper, we investigate the impact of CCC-Noise on the quality of a popular generative classifier, normal discriminant analysis (NDA), and its corresponding discriminative classifier, logistic regression (LR). We consider the problem of two multivariate normal populations having a common covariance matrix. We compare the asymptotic distribution of the misclassification error rate of these two classifiers under CCC-Noise. We show that when the noise level is low, the asymptotic error rates of both procedures are only slightly affected. We also show that LR is less deteriorated by CCC-Noise compared to NDA. Under CCC-Noise contexts, the Mahalanobis distance between the populations plays a vital role in determining the relative performance of these two procedures. In particular, when this distance is small, LR tends to be more tolerable to CCC-Noise compared to NDA.
Relationship between feeding behavior and residual feed intake in growing Brangus heifers

Residual feed intake (RFI) is a measure of feed efficiency defined as the difference between actual feed intake and expected feed intake required for maintenance and production. The objective of this study was to determine the relationship between RFI, feeding behavior, and other performance traits in growing heifers. Individual DMI was measured in Brangus heifers (n = 115) fed a roughage-based diet (ME = 2.0 Mcal/kg) for 70 d using Calan-gate feeders. Residual feed intake was computed as the residuals from linear regression of DMI on mid-test BW(0.75) and ADG. Heifers with the greatest (least efficient, n = 18) and least (most efficient, n = 18) RFI were identified for quantification of feeding behavior traits. Continuous video recordings were obtained for all heifers during d 28 through d 56 of the 70-d feeding trial. Video data of 2 replications of four 24-h periods, 2 wk apart, were analyzed for the focal heifers. A head-down feeding event was defined as a heifer positioned in the feeder with her head lowered. A meal included all head-down feeding events that were separated by less than 300 s. The mean RFI for the high- and low-RFI heifers were 1.00 and -1.03 +/- 0.03 kg/d, respectively. High-RFI heifers consumed 21.9% more (P < 0.0001) DM but had similar BW and ADG compared with low-RFI heifers. The high-RFI heifers spent less time in head-down feeding events per day (P < 0.0001; 124 vs. 152 +/- 4.3 min/d), consumed DM at a faster rate (99.6 vs. 62.8 +/- 3.3 g/min), and ate more often per day (119.1 vs. 90.5 +/- 3.9 head-down feeding events/d) compared with the low-RFI heifers; however, meal duration and frequency were not related to RFI. We conclude that feeding behavior related to head-down feeding events may be more useful as an indicator of RFI than the number of meal events.
Pediatric splenic injuries with a contrast blush: successful nonoperative management without angiography and embolization

Abstract Background The presence of a contrast blush on computed tomography (CT) in adult splenic trauma is a risk factor for failure of nonoperative management. Arterial embolization is believed to reduce this failure rate. The significance of a blush in pediatric trauma is unknown. The authors evaluated the outcome of children with blunt splenic trauma and contrast extravasation. Methods The trauma registry was queried for all pediatric patients with blunt splenic injuries. Admission CT was reviewed for injury grade and presence of an arterial blush by a radiologist blinded to patient outcome. Hospital and office charts were reviewed for success of nonoperative management, late splenic rupture, and other complications. Results One hundred seven children with blunt splenic trauma were identified over a 6-year period. Mean injury grade was 2.9. Six patients required emergency splenectomy. An additional 7 patients met hemodynamic criteria for surgical intervention (3 splenectomies, 4 splenorrhaphies). Admission CT was available in 63 patients. An arterial blush was identified in 5 (9.7%). Four remained stable and were treated conservatively. One underwent splenectomy for hemodynamic instability. There were no cases of delayed splenic rupture, failed nonoperative treatment, or long-term complications. Conclusions Contrast blush in children with blunt splenic trauma is rare, and its presence alone does not appear to predict delayed rupture or failure of nonoperative treatment. Based on this limited series, splenic artery embolization does not have a place in the management of splenic injuries in children.
Synthesis, characterization, and cyclic stress-influenced degradation of a poly(ethylene glycol)-based poly(beta-amino ester).

This study aims to fundamentally understand the polymer network formed by poly(ethylene glycol) diacrylate (PEGDA) MW 700 and 3-methoxypropylamine (3MOPA) as well as to characterize the degradation response of this material with and without applied cyclic stress. Macromer reaction chemistry was confirmed by 1H NMR measurements. UV calorimetry analysis revealed conditions of network formation were dependent on molecular weight of the PEGDA monomer and light intensity. The glass transition temperature of all networks PEGDA MW 258, 575, and 700 were measured and found to be in the range of −40 to −30°C with a rubbery moduli ranging from 4 to 10 MPa by DMA. Degradation studies were performed with and without applied cyclical stress, and in most cases, elastic modulus decrease and mass loss occurred steadily over a 24-h period. Unexpected partial crystallization was discovered to occur in the networks containing higher molecular weight PEGDA in the presence of humidity and high frequency cyclic loading. In all materials, high frequency applied cyclic loading during in situ degradation resulted in catastrophic fracture of the material prior to an appreciable decrease in modulus. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Management of Long-Term Ketogenic Parenteral Nutrition

The ketogenic diet (KD) is a well-accepted treatment modality for children with intractable epilepsy and for inborn errors of carbohydrate metabolism. These children, just as any other child, may b...
Fine needle aspiration cytology of hepatobiliary cystadenoma with mesenchymal stroma.

BACKGROUND Hepatobiliary cystadenomas (HBCs) with mesenchymal stroma (MS) are rare cystic neoplasms occurring exclusively in women. Hepatobiliary cystadenoma consists of a mucin-producing cyst lining epithelium underlined by a dense MS cell layer. In the current study, the authors review the fine needle aspiration cytology of HBC with MS and identify characteristic cytologic features that suggest such an uncommon neoplasm on aspirates. METHODS A search of the histopathology files at the University of Texas Medical Branch at Galveston for the interval of January 1992 through December 2000 yielded four cases of HBC having both cytologic and histologic specimens. The cytologic features of the aspirates were reviewed and correlated with the clinical history, radiologic findings, and the histopathology of the excised specimens. RESULTS All four patients were middle-aged women (mean age, 48.5 years) who presented with epigastric pain radiating to the back, due to large cystic lesions in the right liver lobe (three patients) or the left liver lobe (one patient). Aspiration cytology revealed chronic inflammatory exudate in all cases, along with occasional aggregates of bland, cuboidal-columnar epithelial cells (in three cases), which rarely arranged in papillary clusters. No significant atypia, evidence of malignancy, or MS cells were identified on the aspirates. HBC with MS was confirmed histologically on the excised specimens in all cases. CONCLUSIONS By ensuring adequate sampling and correlating with consistent clinical and radiologic findings, a diagnosis of HBC or cystic hepatobiliary neoplasm can be suggested on the basis of aspiration cytology. Cancer (Cancer Cytopathol) 2002;96:37–42. © 2002 American Cancer Society. DOI 10.1002/cncr.10315
A cellular activator of catecholamine-sensitive adenylate cyclase in rat reticulocytes and erythrocytes: Changes during reticulocyte development and effects on the β receptor

Abstract Rat reticulocytes contain an isoproterenol-sensitive adenylate cyclase activity which is lost with maturation to erythrocytes despite no change in the density of β-adrenergic receptors. To explore this observation, a cytosol factor, previously shown to be important in the expression of catecholamine-sensitive adenylate cyclase in the reticulocyte, was compared to a cytosol factor obtained in a similar manner from mature erythrocytes. The cytosol factor from reticulocytes augmented isoproterenol-responsive adenylate cyclase activity in reticulocyte and erythrocyte membranes half-maximally at 0.7 ± 0.1 (SEM) and 1.1 ± 0.3 μg/ml, respectively. These concentrations of reticulocyte-derived cytosol factor were significantly lower ( P P m ; P
Aerosol dynamics modeling of silicon nanoparticle formation during silane pyrolysis: a comparison of three solution methods

A numerical model has been developed to predict gas-phase nucleation, growth, and coagulation of silicon nanoparticles formed during thermal decomposition of silane. A detailed chemical kinetic model of particle nucleation was coupled to an aerosol dynamics model that includes particle growth by surface reactions, coagulation with instantaneous coalescence, and convective transport. Solution of the aerosol general dynamic equation was handled by three approaches: (1) the efficient and reasonably accurate method of moments; (2) the quadrature method of moments, which requires no prior assumption of the shape of the particle size distribution; and (3) a computationally more expensive sectional method (SM). The SM includes a conceptually simple and computationally efficient algorithm for treating coagulation that is found to be superior to widely used methods from the literature. All three approaches gave similar results for the evolution of the first few moments of the particle size distribution. The SM was able to capture the bimodal distribution that appears briefly at short residence times due to simultaneous nucleation and coagulation. At longer residence time, only coagulation remains important and both the sectional and moment methods give very similar results as they approach the self-preserving size distribution.
Light-stimulated cotyledon expansion in the blu3 and hy4 mutants of Arabidopsis thaliana

Cotyledon expansion in response to blue light was compared for wild-type Arabidopsis thaliana (L.) Heynh. and the mutants blu3 and hy4, which show reduced inhibition of hypocotyl growth in blue light. White, blue, and red light stimulated cotyledon expansion in both intact and excised cotyledons of wild-type seedlings (ecotypes No-0, WS, Co-0, La-er). Cotyledons on intact blu3 and hy4 seedlings did not grow as well as those on the wild type in response to blue light, but pretreatment of blu3 seedlings with low fluence rates of red light increased their responsiveness to blue light. Excision of cotyledons alleviated the mutant phenotype so that both mutant and wild-type cotyledons grew equally well in blue light. The loss of the mutant cotyledon phenotype upon excision indicates that the blu3 and hy4 lesions affect cotyledon expansion indirectly via a whole-plant response to light. Furthermore, the ability of excised, mutant cotyledons to grow normally in blue light shows that this growth response to blue light is mediated by a photosystem other than the ones impaired by the blu3 and hy4 lesions.
Rocking buoy wave energy converter

Abstract A device for converting ocean wave energy into electricity utilizing a rocking buoy and a hydrogen pressure cell is described. The moored buoy contains a pneumatic tube filled with a dense liquid which rocks back and forth as a result of the ocean wave activity. Hydrogen gas, maintained above the dense fluid is alternatively compressed and expanded by the moving fluid. The hydrogen gas communicates with a hydrogen pressure cell and the resulting pressure difference across the cell leads to an electrical voltage and under load, to electrical power.
Coiling Direction Ratios of Foraminifera Globigerina pachyderma (Ehrenberg) in Northeastern Pacific Surface Sediments: ABSTRACT

Coiling direction ratios of Globigerina pachyderma (Ehrenberg) plotted for sediment surface samples from the northeastern Pacific north of 40°N. did not show the consistent relationship which would recommend them as reliable guides for deep-sea core analysis in this region. A generally increasing tendency for sinistral coiling toward the north was noted, from 13 per cent left reported by Parker (1962) from a nearshore sample (40°N.) to a consistent 95-100 per cent left in the northern Gulf of Alaska. Great irregularity in coiling ratios in seaward (east-west) traverses may be related to a nearshore area of warm-water intrusion (Fleming, 1958) affecting the type of plankton supplied to the substrate. Variations from 20-96 per cent left coiling were observed in th se traverses. Dextral coiling percentage usually was higher in samples containing many species and few individuals. The "recency" of the surface sample also affected the coiling ratios. The problem of distinguishing small Globoquadrina dutertrei (d'Orbigny)--predominantly right coiling--from Globigerina pachyderma (coiling in question) may qualify coiling ratios reported by various authors. Plankton tow samples off Oregon, Washington, and the Aleutian Islands had smaller percentages of G. pachyderma and higher dextral ratios than samples from the underlying sediment surface. End_of_Article - Last_Page 1760------------
True Blue Inorganic Optoelectronic Devices

The realization of blue light-emitting optoelectronic deviceshas attracted much attenion. Here the leading candidates (ZnSe, GaN, SiC, organic polymers) are examined and research towards the improvement of zinc selenide in particular is reviewed. Deposition methods, precursors, and p-type dopants are all discussed. The Figure shows a p–n junction after equilibration.
Spantide: failure to antagonize bombesin-induced stimulation of gastrin secretion in dogs.

Abstract Spantide ([d-Arg1,d-Trp7,9,Leu11]substance P) was shown to function not only as a substance P receptor antagonist but also as a bombesin receptor antagonist. This study examined the effects of spantide on intravenous bombesin-induced stimulation of gastrin and acid secretion. Dogs were infused with spantide (1 or 10 nmol kg−1 hr−1) or saline and bombesin (60 pmol kg−1 hr−1), and the gastric acid and plasma gastrin responses were monitored. Spantide did not significantly modify gastrin or gastric acid secretion induced by bombesin. It is concluded that spantide may not be a useful bombesin antagonist for in vivo studies.
Homocysteine and Hypomethylation: A Novel Link to Vascular Disease

A mild elevation in serum homocysteine levels is an independent risk factor for arteriosclerosis and venous thrombosis. Despite the clinical significance of homocysteine, however, the molecular mechanisms of homocysteine-induced arteriosclerosis have not been completely elucidated. This lack of understanding is due in large part to the excessively high concentrations of homocysteine (greater than 1 mM) used in experiments. Many of homocysteine's effects have been attributed to its prooxidant activity, which is implicated as the mechanism through which it inhibits production of endothelium-derived relaxing factor and activates quiescent vascular smooth muscle cells. We have found that homocysteine at 10 to 50 microM (but not cysteine) inhibits progression of the vascular endothelial cell cycle at or before the G1-S junction. This inhibition appears to be mediated by decreases in the carboxyl methylation, membrane association, and activity of p21ras--a major G1 regulator. Homocysteine may play an important role in promoting arteriosclerosis by inducing endothelial dysfunction, by inhibiting endothelial cell regeneration, and by directly activating quiescent vascular smooth muscle cells.
A unified model for the prediction of bubble detachment diameters in boiling systems—II. Flow boiling

An improved model is proposed for the prediction of departure and lift-off diameters in saturated forced convection boiling. The model utilizes a force balance similar to that proposed by Klausner et al. (Int. J. Heat Mass Transfer 36, 651–662 (1993)). One significant improvement is that the inclination angle is determined on a dynamic basis and is not required as an input. Furthermore, it is hypothesized that the surface tension force is small compared to other forces acting on a vapor bubble at the points of departure and lift-off, and thus information on the bubble contact diameter and contact angles is not required. A new data set on mean vapor bubble lift-off diameters and probability density functions (pdf's) for flow boiling of refrigerant R113 on a nichrome heating strip has been obtained using the experimental facility described by Klausner et al. (Int. J. Heat Mass Transfer 36, 651–662 (1993)). The wall superheat and mean liquid velocity respectively range from 5.5 to 12.0 °C and 0.35 to 1.0 m s−1. It is demonstrated that over the limited range of flow boiling conditions considered, the predicted departure and lift-off diameters agree well with measured values.
The management of infected penile implants

Penile prosthesis implantation is associated with a relatively low rate of wound infection (3%). The most common organism in most reported series isS. epidermidis, followed by the gram-negative coliforms. Strict adherence to antiseptic principles, together with the use of prophylactic antiseptic principles, together with the use of prophylactic antibiotics, keeps the incidence of infection low. If an infection occurs, either the prosthesis should be promptly removed or a salvage or rescue procedure should be considered by which the device is removed, the wound cleansed, and a new prosthesis inserted.
Early and late outcome following deployment of a new flexible tantalum intracoronary stent in dogs.

Abstract A new rediopaque, highly flexible balloon-expandable tantalum stent was tested. Thirty-six of 40 stents were successfully deployed percutaneously in the coronary arteries of 31 dogs. The dogs were given aspirin before, intravenous heparin during, and aspirin alone after the procedure. One dog died at 24 hours because of coronary occlusion following traumatic implantation. Four dogs were put to death early, revealing reendothelialization by 9 days. Eleven dogs were put to death from 2 weeks to 9 months during long-term follow-up, showing all vessels widely patent with the stent uniformly embedded within a stable neointimal layer. Follow-up arteriography showed patency in all remaining stents up to 1 year, with no perforation or aneurysm formation. Four stents were placed into canine peripheral arteries and were removed percutaneously after deployment. Pathology revealed no significant trauma to involved vessels. This tantalum stent exhibits feasibility of percutaneous deployment, early neointimal formation, low thrombogenicity on long-term aspirin therapy alone, and patency up to 1 year in this canine model.
Surface lithofacies, biofacies, and diatom diversity patterns as models for delineation of climatic change in the southeast Atlantic Ocean

Abstract Distribution of diatom species in surface sediments of the southeast Atlantic Ocean is regulated by present-day oceanographic and hydrodynamic processes. Five assemblages (vectors) defined by factor-vector analysis, reflect different environments and conditions. Assemblage A is a high diversity flora associated with the nutrient-rich, relatively cold waters south of the Polar Front in the diatom ooze belt. Occurrence of this flora on Maud Rise and vicinity may reflect periodic occurrence of a polynya in that area. Assemblage B is a reworked assemblage that dominates the southern portion of the study area. Productivity there is low, reflecting sea ice cover during most of the year. The area north of the Polar Front is dominated by Assemblage C, whose characteristic species reflect the relatively warm Subantarctic Surface Water. Winnowing and frustule breakage have altered Assemblage D (found in three isolated samples) by removing relatively delicate forms leaving lag deposits of more robust species. Assemblage E is a low diversity stress flora, reflecting unstable, unpredictable environments along the Polar Front, Antarctic slope, and the northern boundary of winter sea ice. These sites are characterized by the sinking of cold water. Downcore analysis of cores lying adjacent to the Polar Front and the diatom ooze—pelagic clay boundary show evidence for past climatic variation. The low trophic level occupied by diatoms and the subsequent sensitivity of these organisms to abiotic environmental parameters such as light quality, make relative diatom abundance a useful tool for monitoring fluctuations of winter sea ice and the temperature changes responsible for these fluctuations. The position of the Polar Front has migrated at least three times within the last 0.015 m.y. B.P. Within the last 0.3 m.y. B.P. warm maxima have occurred at approximately 0.0, 0.015, 0.125 and 0.3 m.y. B.P.
GROWTH, YIELD, AND ION RELATIONS OF STRAWBERRY IN RESPONSE TO IRRIGATION WITH CHLORIDE-DOMINATED WATERS

Strawberry is listed as the most salt sensitive fruit crop in comprehensive salt tolerance data bases. Recently, concerns have arisen regarding declining quality of irrigation waters available to coastal strawberry growers in southern and central California. Over time, the waters have become more saline, with increasing sodium (Na+) and chloride (Cl−). Due to the apparent extreme Cl− sensitivity of strawberry, the rising Cl− levels in the irrigation waters are of particular importance. In order to establish the specific ion causing yield reduction in strawberry, cultivars ‘Ventana’ and ‘Camarosa’ were grown in twenty-four outdoor sand tanks at the ARS-USDA U. S. Salinity Laboratory in Riverside, CA and irrigated with waters containing a complete nutrient solution plus Cl− salts of calcium (Ca2+), magnesium (Mg2+), Na+, and potassium (K+). Six salinity treatments were imposed with electric conductivities (EC) = 0.835, 1.05, 1.28, 1.48, 1.71, and 2.24 dS m−1, and were replicated four times. Fresh and dry we...
GLC determination of methenamine in tablets.

A rapid and sensitive GLC method was developed for the quantitative determination of methenamine in tablets. The method was shown to possess several advantages over the official NF assay. After dissolution of the whole tablet in absolute ethanol and addition of an internal standard (pentylenetetrazol), an aliquot was injected into the gas chromatograph for analysis. The sample was chromatographed using a stainless steel column packed with 10% OV-17 on Chromosorb W-HP. Quantitation was achieved by measuring peak heights. The simplicity, directness, extreme rapidity, and accuracy of the method represent an improvement over the official method and the other proposed assays.
Analysis of cell surface properties using derivatized agarose beads

An assay has been developed to analyse cell surface properties using agarose beads derivatized with amino acids, sugars, proteins, and other molecules. The assay is simple and rapid and is useful to identify new cell surface markers. Various species and strains of yeast, paramecium, and Euglena were tested for their ability to bind to over 100 types of derivatized beads. A variety of specificity studies were performed in order to understand the nature of cell-bead binding. Our results indicate that cell-bead binding is often specific enough to distinguish between configurational isomers and spacer sizes and can be blocked by addition of specific molecules to the incubation medium. In some cases, different species or strains differed only by their binding to a single bead type. This simple and rapid assay may help to uncover new cell surface receptors and may lead to the development of clinically useful compounds for therapeutic applications.
Surface behavior of heat exchanger tubes in fluidized-bed combustors☆

Abstract The combustion-side surfaces of both in-bed and convection-pass heat exchanger tubes in bubbling-bed and circulating-bed fluidized-bed combustors are subject to metal wastage by erosion-corrosion. The formation of an in situ protective coating of the absence of such a coating determines the metal wastage which occurs. The rates and mechanisms of the metal loss are complex functions of the characteristics of the particles, i.e. their composition, shape, size, strength and reactivity and of the conditions occurring in the combustors, i.e. temperature, particle velocity and impact angle, gas reactivity, solids loadings and duration. These factors have been experimentally investigated and the requirements which must be satisfied in order that materials may have longer service lives have been identified. The tests were conducted using particles from several locations in two different circulating fluidized-bed combustors (CFBCs). Tests were carried out under conditions which nearly simulated those in CFBCs. The behavior of the surfaces of mild steel was determined.
An Intuitive Introduction to Blockmodeling with Examples

Une introduction intuitive aux modeles en blocs avec des exemples. Cet article presente une definition intuitive des modeles en blocs (blockmodels). Il debute par une discussion Informelle des concepts de roles. de relations, et d'equivalences avant de presenter le concept du modele en blocs comme un modele des structures de roles. Le concept d'un reseau social est introduit ensuite et ces deux derniers concepts sont reunis pour suggerer l'idee que les concepts de modelisation en blocs peuvent etre utilises pour partitionner un reseau social. Cette partie est suivie d'une discussion de l'approche directe pour etablir des modeles en blocs. Deux exemples empiriques sont developpes en detail. Une generalisation naturelle de la modelisation en blocs est presentee et developpee.
The Person Behind The Word: Mead's Theory Of Universals And A Shift Of Focus In Symbolic Interactionism

Careful consideration of Mead’s theory of universals proves to be a corrective to a number of tendencies evident in the work of at least some influential contemporary symbolic interactionists. Mead avoids any realistic hypostatization of separate universals (“meanings,” “forms,” or “essences” while at the same time eschewing nominalistic and conventionalistic views of language. His principle of the objective reality of perspectives (1932:161-175) allows him to grant objective reality to universal characteristics of concrete objects, but entails neither hypostatization nor idealization of the universal. In addition to contravening nominalism and conventionalism, Mead’s theory of universals provides a perspective from which the reality of the self, and the importance of intentional action for the development of a firmly felt sense of self and autonomy, can both be affirmed. Far from being an illusion or mere symbolic construct, the self is seen to be an objectively real universal within the perspective of social action. LONG AGO, Dewey asserted that man was active and, on that score, there was nothing else to be said. Action could be taken as a “given”-as a descriptive factwhich, at least in Dewey’s time, was more productively assumed than explained. It is understandable that early symbolic interactionists recommended this strategy since most available theories seeking an explanation as to why man was active were limited to a biological tissue-deficit model that precluded the very symbolic realm that was critical to the sociologist. For example, Stone and Farberman (1970:467) defend Dewey’s strategy on just these grounds:
High Expression Hampers Horizontal Gene Transfer

Horizontal gene transfer (HGT), the movement of genetic material from one species to another, is a common phenomenon in prokaryotic evolution. Although the rate of HGT is known to vary among genes, our understanding of the cause of this variation, currently summarized by two rules, is far from complete. The first rule states that informational genes, which are involved in DNA replication, transcription, and translation, have lower transferabilities than operational genes. The second rule asserts that protein interactivity negatively impacts gene transferability. Here, we hypothesize that high expression hampers HGT, because the fitness cost of an HGT to the recipient, arising from the 1) energy expenditure in transcription and translation, 2) cytotoxic protein misfolding, 3) reduction in cellular translational efficiency, 4) detrimental protein misinteraction, and 5) disturbance of the optimal protein concentration or cell physiology, increases with the expression level of the transferred gene. To test this hypothesis, we examined laboratory and natural HGTs to Escherichia coli. We observed lower transferabilities of more highly expressed genes, even after controlling the confounding factors from the two established rules and the genic GC content. Furthermore, expression level predicts gene transferability better than all other factors examined. We also confirmed the significant negative impact of gene expression on the rate of HGTs to 127 of 133 genomes of eubacteria and archaebacteria. Together, these findings establish the gene expression level as a major determinant of horizontal gene transferability. They also suggest that most successful HGTs are initially slightly deleterious, fixed because of their negligibly low costs rather than high benefits to the recipient.
Futurologists Look Back

The gulf between indigenous and western experiences in the Americas may appear so vast as to obscure the relevance of knowledge about the ancient past to challenges of today. Yet, in imaging alternative futures, people of varied cultural dispositions find experiential accord. As both product of and precedent for social action, materiality provides archaeologists some purchase on interventions of change. In the recursive relationships between place and being, between thing and entanglement, we observe temporalities that privilege historical practice as the locus of social action. Examples from the ancient American Southeast illustrate what form an archaeology of alternative futures might take.
Using the Creative Product Semantic Scale as a Metric for Results‐Oriented Business

The advantages to businesses of using the Creative Product Semantic Scale (CPSS), a reliable, valid instrument that measures novelty, resolution, and style, are presented. The word ‘product’ is broadly defined to include an idea, proposal, process, prototype, or tangible product. Research shows that the CPSS has helped businesses in testing for marketability, new product design, product improvement and enhancement of advertisements. Future applications of the CPSS include improving the screening of ideas, diagnosis of brand problems, competition analysis, and team processes. A new on-line version of the CPSS provides a convenient method of administration.
Chemical anchoring of platinum in zeolites

Abstract Platinum particles in zeolite Y, after reduction at 559°C were found to be significantly smaller if the zeolite contained Fe2+ or Cr3+ ions. The XRD peaks of Pt are dramatically reduced with increasing content of these ‘chemical anchors’, and in the case of Fe2+ ions the dispersion expressed by the H/Pt ratio, is enhanced significantly up to an atomic ratio of Fe/Pt ≅ 0.5. The Fe2+ ions act not only as anchors but also as catalyst promoters; the increase in rate of benzene hydrogenation is found significantly higher than can be accounted for by the enhanced dispersion of Pt.
Canine testicular tumors: Epidemiologic features of 410 dogs

Histologically confirmed testicular tumors were diagnosed in 410 dogs from 12 North American veterinary university hospitals and clinics. Three tumor-cell types, Sertoli cell tumor, interstitial cell tumor and seminoma, were about equally represented. Several breeds were identified with high risk for different testicular tumor-cell types. Cytogenetic and immunogenetic studies of these dog families could offer leads applicable to familial testicular cancer in man. The multiplicity of breeds within the series suggests that, as in man, other factors, in addition to hereditary, play a role in etiology. Cryptorchid dogs appear to have a 13.6 times higher risk of testicular tumor than normal dogs. Additionally, male dogs with an inguinal hernia have an increased risk (4.7) of testis tumors. There were no detectable excesses of other urogenital anomalies or urogenital tumors among the series. The Shetland Sheepdog is suggested as an appropriate model for research into the mechanisms responsible for testicular maldescent and tumorigenesis.
Using wireless technology to provide basic telephone service in the developing world

Abstract Low-tier wireless systems offer great promise for the provision of basic telephone service in the developing world. Such systems offer the advantages of rapid deployment, minimal disruption during construction, and low cost. This paper examines the level of investment required to deploy such systems, exploring the question in the context of a number of design constraints and parameters. The analysis shows that the investment required to build a low-tier wireless system compares quite favorably with that of a conventional cable-based system. The paper concludes with some policy implications of the work that are relevant to national governments and telephone carriers in the developing world.
A facile synthetic approach to 7-deazaguanine nucleosides via a Boc protection strategy

An efficient route to the preparation of 5-substituted 2-amino-7-((2R,4R,5R)-tetrahydro-4-hydroxy-5-(hydroxymethyl)furan-2-yl)-3H-pyrrolo[2,3-d]pyrimidin-4(7H)-one compounds has been developed by the condensation of omega-substituted aldehydes with 2,6-diaminopyrimidin-4(3H)-one, followed by Boc protection to afford the corresponding N(2),N(2),N(7)-tris-Boc-O(4)-t-Bu-5-substituted 2-amino-3H-pyrrolo[2,3-d]pyrimidin-4(7H)-one, which is amenable to direct condensation with 1-chloro-2-deoxy-3,5-di-O-p-toluoyl-alpha-D-erythro-pentofuranose. This route affords an efficient synthesis to 2-amino-3H-pyrrolo[2,3-d]pyrimidin-4(7H)-one, 2-amino-5-alkyl-3H-pyrrolo[2,3-d]pyrimidin-4(7H)-one, and guanine nucleosides.
Ultrathin, Hyperbranched Poly(acrylic acid) Membranes on Porous Alumina Supports

The synthesis of high-flux composite membranes requires deposition of an ultrathin, discriminating layer on a highly permeable support. This paper describes the synthesis, derivatization, and characterization of hyperbranched poly(acrylic acid) (PAA) membranes on porous alumina supports. PAA films as thin as ∼40 nm effectively cover underlying pores without filling them, presumably because of their hyperbranched structure. Synthesis of these films begins by sputtering a thin gold layer on the alumina support and then grafting a layer of PAA to a self-assembled monolayer of mercaptoundecanoic acid on the gold. Graft-on-graft deposition of PAA yields the hyperbranched membrane. FESEM (field-emission scanning electron microscopy) and AFM (atomic force microscopy) images clearly show that hyperbranched PAA films can completely cover the substrate surface without filling underlying pores, thus creating an ultrathin membrane on a porous support. PAA membranes are especially attractive because derivatization per...
The excess enthalpies of six p-xylene + alcohol mixtures at 298.15 K

Abstract The excess enthalpies of p -xylene + methanol, + ethanol, + n -propanol, + n -butanol, + n -pentanol, and + n -hexanol were measured at 298.15 K with an isothermal flow calorimeter with a reproducibility of better than 1 per cent. All mixtures showed endothermic mixing with the maximum values of the excess enthalpies occurring in the p -xylene rich region.
Ecological Psychology and Social Psychology: Continuing Discussion

What form would an ideal merger of ecological and social psychology take? Is that ideal attainable? Many researchers and theorists are working to answer these questions. Charles (2009, 2011a) offered insights from E. B. Holt, one of James J. Gibson's mentors, who argued that minds-mental kinds, processes, states, etc.-are observable aspects of the environment. Phrasing that in Ecological terms, the minds of other organisms are specified in the structure of ambient energy extended over time and space; they are directly perceivable by a properly attuned organism. Ecological Psychology enhances Holt's story, by brining to the table a sophisticated theory of direct perception; Holt enhances the Ecological story by brining to the table a sophisticated theory about the nature of minds. The two combine to form the long-sought ideal merger. Thus, I claimed, Ecological Psychology will either rediscover its roots, or go through the trouble of re-creating them. This paper further develops those ideas, by presenting a simpler version of the argument, suggesting easy ways of dismissing that argument, and addressing the concerns expressed by Castro and Lafuente (2011).
Modeling cardiac β-adrenergic signaling with normalized-Hill differential equations: comparison with a biochemical model.

Background New approaches are needed for large-scale predictive modeling of cellular signaling networks. While mass action and enzyme kinetic approaches require extensive biochemical data, current logic-based approaches are used primarily for qualitative predictions and have lacked direct quantitative comparison with biochemical models.
Chlorpromazine, a useful antiemetic in pediatric practice.

Summary Chlorpromazine has been used in clinical pediatric practice for a wide variety of nonalimentary conditions associated with vomiting. It has given surprisingly favorable symptomatic results in 75 per cent of the ninety infants and children so treated. A mildly sedative side effect was noted. In our clinical experience it appears to be the first agent generally available that has this antiemetic effect which is presumed to operate by raising the threshold of the emetic centers in the central nervous system.
Aggressive management of elderly patients with muscle-invasive bladder cancer.

Radical cystectomy, the gold standard for treatment of muscle-invasive bladder cancer, has traditionally been withheld from elderly patients because of morbidity and mortality concerns. In this Viewpoint, the authors argue that aggressive management is safe and effective in select elderly patients.