cssi/SciSciGPT-SciSciNet huggingface dataset:
Vibration of moderately thick square orthotropic stepped thickness plates

Abstract Numerous studies that address the vibration of stepped thickness plates are reported in the literature. Predominately, classical plate theory has been used to formulate studies for both isotropic and anisotropic stepped plates. Mindlin plate theory has been employed to obtain results for thick isotropic stepped thickness plates. Exact solutions, Rayleigh–Ritz, differential quadrature and finite element methods have been employed to compute results for frequency of vibration. Results for frequency of vibration for thick orthotropic stepped thickness plates are presented here using orthorhombic material properties of aragonite. The finite element method has been used to compute frequencies and determine mode shapes for simply supported and clamped square Mindlin plates.
Graduate degrees and job success: Managers in one U.S. Corporation

Abstract Previous research has assumed that earnings reflect productivity. This study compares the relationship between education and earnings to that between education and more direct measures of productivity. Using the personnel files of managers in a large corporation, the author estimates the effects of various graduate degrees on four measures of productivity: annual salary, change in salary, supervisor's rating and probability of promotion. Graduate degrees were found to be positively related to within-grade salary and sometimes to salary increases, but negatively related to all other measures of job performance. Thus graduate degrees are not associated with greater job productivity, as measured here.
Simulation and measurement of a vertical Bridgman growth system for β-NiAI crystal

A coordinated theoretical and experimental study of the temperature distribution inside a customized vertical Bridgman system for growing β-NiAl crystal has been conducted. The theoretical model accounts for the combined effects of phase change dynamics, the coupled heat transfer processes of conduction, convection and radiation, variable material properties, and complex geometry pertaining to the system. Comparisons between numerical predictions and experimental measurements show satisfactory agreement. The accuracy of the melting temperature of NiAl with stoichiometric composition, along with important processing parameters such as interface curvatures and temperature gradients across the interface, have been discussed in detail. Also assessed are possibilities of improving the solidification process, including coating the ampoule outer wall with a material of high radiative emissivity or decreasing the ampoule wall thickness.
Work Attitudes of American Indians

Analysis of 22 samples representative of the labor force of the continental United States shows few differences in 13 work attitudes between American Indians (n= 732) and European Americans (n= 12,810). American Indians were more insecure in their jobs and were less satisfied with their financial situation. They were more likely to prefer a job that offers a high income and chances for promotion. As their increasing earnings reach parity and the effects of discrimination and prejudice lessen, these few differences should diminish.
Activation of extra copies of genes coding for nitrogenase in Rhodopseudomonas capsulata

Biological nitrogen fixation requires the nitrogenase enzyme complex, ATP, and a strong reductant1. Klebsiella pneumoniae contains 15 linked nitrogen fixation (nif) genes2,3, three of which, nifH, nifD and nifK have been sufficiently conserved in evolution that cloned K. pneumoniae nifHDK DNA4 will hybridize to DNA sequences from every nitrogen-fixing bacterium examined to date, including the purple, non-sulphur bacterium Rhodopseudomonas capsulata5, in which one complete nifHDK operon has been mapped6. Using cloned K. pneumoniae nifHDK DNA we report here that R. capsulata contains multiple copies of the genes for nitrogenase components. Two regions containing sequences homologous to all three nif structural genes have been identified, and mutations in one region produced a Nif− phenotype. Nif+ pseudorevertants were derived from these mutants, some of which retained the original mutation suggesting that some of the extra nif gene sequences can be functionally activated.
Space-Charge Effects on the Quadrupole Focusing System in Low-Energy Proton Linear Accelerators

A general computer program has been used to calculate the stability diagram for (+)(-)(+)(-) quadrupole arrangements when the space charge is uniformly distributed in an elliptic cylinder or an ellipsoid. Linearized equations for longitudinal and transverse envelopes of the bunch have been solved simultaneously in order to find the velocity dependence of the phase damping.
Interstitial Growth of Septal Cartilage in the Young Albino Rat

The cartilaginous nasal septa of 28 albino rats were marked with pairs of wire implants. Measurements obtained from cephalometric radiographs taken at 30 and 60 days revealed that the implants invariably separatd and did so at a rate that was highly correlated with the growth of the rest of the snout.
Heart failure awareness week: February 14-21.

The statistics pertaining to heart failure are awesome. It now affects 4.6 million Americans, and 400,000 new cases are diagnosed each year. After a diagnosis is made, less than 50% of patients survive more than five years, and less than 25% survive more than 10 years. Class IV heart failure carries
The Concurrency Challenge

The evolutionary path of microprocessor design includes both multicore and many-core architectures. Harnessing the most computing throughput from these architectures requires concurrent or parallel execution of instructions. The authors describe the challenges facing the industry as parallel-computing platforms become even more widely available.
Gluttonous crimes: Chew, comic books, and the ingestion of masculinity

Synopsis Food-related embodied experiences are entangled in all aspects of subject positions, from ethnicity to class, from age to gender. When it comes to masculinity, food plays a very important role as an arena where various models of masculinity are negotiated. Representations of men around food in a specific medium – comic books and detective stories – can establish, question, reinforce, reproduce or destroy cultural assumptions about masculinity and gender relations. The comic book Chew employs irony and tropes from horror, detective, and action genres to blur gender and ethnic stereotypes about eating and ingestion that are otherwise prevalent in many forms of popular culture, from movies to cookbooks.
Preparation and Evaluation of Zidovudine-Loaded Sustained-Release Microspheres. 2. Optimization of Multiple Response Variables

The formulation of zidovudine-loaded (AZT-loaded) sustained-release microspheres was prepared and optimized using response surface methodology. The objective was to use this statistical procedure to obtain a formulation with optimized overall properties. The effect of formulation variables (emulsifier concentration, drug to polymer ratio, and composition of the internal phase of the emulsion) on a number of response variables was systemically investigated. The response variables were t85, entrapment efficiency, yield, and percentage of loose surface crystals. A desirability function that combines these four response variables was constructed. A second-order polynomial equation was fitted to the data, and the resulting equation was used to predict the responses in the optimal region. All the investigated response variables were found to be highly dependent on the formulation variables, with strong interactions observed between the formulation variables. It was found that optimum overall desirability of AZT microspheres can be obtained at low levels of SDS and ethyl acetate concentrations and at intermediate levels of drug to polymer ratio. An optimized formulation was prepared under these experimental conditions and evaluated for individual responses and overall desirability. The experimental values of the response variables highly agreed with the predicted values.
Ethics and Reporting on Diversity

Morgan, A. N., Pifer, A. I., and Woods, K. (2006). The authentic voice: The best reporting on race and ethnicity. NY: Columbia University Press. 353 pp. $45.00 (Pbk with DVD) As the emphasis on tea...
Accounting quality of German and UK cross‐listings

Purpose – This paper aims to compare the quality of financial reporting (or accounting quality) of firms cross‐listed in Germany and the United Kingdom relative to domestic firms that are not cross‐listed in Germany and the United Kingdom.Design/methodology/approach – The authors assess financial reporting quality based on five measures of earnings management; two measures of timely loss recognition; and the explanatory power (R2) of three models of stock price and returns association with accounting data. Accounting quality is associated with less earnings management, more timely loss recognition and higher stock price/returns association with accounting data.Findings – The authors find that there is no difference in financial reporting quality of firms cross‐listed in Germany and the United Kingdom and domestic firms that do not cross‐list in these countries. They further find that German and UK cross‐listing firms have lower accounting quality than US cross‐listing firms.Research limitations/implicatio...
Catalyst‐Free and Site‐Specific One‐Pot Dual‐Labeling of a Protein Directed by Two Genetically Incorporated Noncanonical Amino Acids

The genetic incorporation of one azide-containing and one keto-containing noncanonical amino acids into a protein at one amber and one ochre mutation sites respectively followed by their orthogonal reactions with one hydroxylamine-containing and one cyclooctyne-containing dyes allows highly efficient one-pot site-specific dual labeling of the protein in a catalyst-free fashion.
Deadlock prediction for Escrow transactions

Abstract The Escrow transactional method permits long-lived transactions to update records without blocking concurrent access by other transactions to records modified. A situation may occur in an Escrow system in which an update request cannot currently be granted, but if the requesting transaction is allowed to wait, the resulting situation is safe in the sense of the banker's algorithm, i.e. a schedule to grant requests exists whereby all current requests can be granted. Any algorithm to find such a schedule must predict potential deadlocks, and we show that this problem is NP-complete, using a variant of a proof by Gold. The proof draws an analogy between transactional deadlock prediction and the banker's algorithm, and thus is of independent interest. In the conclusions of Section 5 we point out some basic negative performance ramifications of deadlock avoidance/detection inherent in the standard approach of the banker's algorithm; this suggests an avenue for further research.
Sodium transport in red blood cells from dialyzed uremic patients

Sodium transport in red blood cells from dialyzed uremic patients. Studies on red blood cell (RBC) sodium (Na) transport in chronic renal failure have described abnormalities in the ouabain–sensitive Na, K pump. We now report Na transport in RBC using cation flux methodology, measuring both the ouabain–sensitive Na, K pump and the ouabain–insensitive Na, K cotransport (CoT) and Na, lithium (Li) countertransport (CTT) in 28 subjects on hemodialysis, eight subjects on chronic ambulatory peritoneal dialysis (CAPD) and 29 control subjects. Intracellular cation content and passive permeability of Na were also examined. Mean Na efflux through the ouabain–sensitive Na, K pump was not reduced in dialysis patients when compared to normal subjects, whether measured in fresh cells (1.41 ± 0.05 vs. 1.30 ± 0.03 mmole/liter RBC/hr; P
Radiation-induced crosslinking: III. Effect on the crystalline and amorphous density fluctuations of polyethylene

Small-angle x-ray scattering (SAXS) was used to determine density fluctuation in radiation-induced crosslinked polyethylene of varying degrees of crystaUinity. Den- sity fluctuation FL decreases with increasing crystallinity, while it increases linearly with increasing radiation dose or degree of crosslinking. By means of extrapolation, density fluctuations in the crystalline and the amorphous phases FLc and FG were obtained. At a given dose, Faa is greater than FLc. The increase in FLa with radiation is found to be much greater than that of FLc compared with the initial values at 0 Mrad, FLc showing only a negligible increase even at 312 Mrad. The present findings suggest that crosslinks are not introduced within the crystalline phase; they take place pmnarlly in the noncrystalline phase, in agreement with the conclusions reached previously on the basis of changes in crystalline and amorphous densities in irradiated polyethylene.
Alcohol and marijuana consumption among undergraduate polydrug users.

Of 365 undergraduates surveyed, 42% admitted to polydrug use. The rank order of drugs used was: alcohol, marijuana, tobacco, hallucinogens, barbiturates, amphetamines, cocaine, opiates, and inhalants. Forty-four percent used one drug combination, 25% used 2 to 3 combinations, 17% used 4 to 7 combinations, with 14% using 8 to 14 combinations. Nealry 85% used alcohol plus marijuana, with nearly one-third combining alcohol or marijuana with barbiturates, hallucinogens, or amphetamines. Alcohol appeared to be the first drug used; however, it was not abandoned when marijuana use began-both drugs were simply used concurrently, and new drugs were incorporated into the existing patterns of drug use. Interpretations of polydrug use are limited by difficulties in assessing drug use, as well as inconsistencies in the chemical composition of illicit drugs.
Irradiation of Diapausing and Nondiapausing Larvae of Plodia Interpunctella: Effects on Larval and Pupal Mortality and Adult Fertility

Diapausing (D) and nondiapausing (ND) 5th stage larvae of a synthesized field strain of Plodia Interpunctella (Hubner) that incorporated 12 separate field populations were irradiated with a graded series of gamma doses from 2.5–20 krad. None of the ND larvae were killed by doses of 7.5–20 krad but 88 to 100% of the D larvae died before pupation. Diapausing larvae often lived for many weeks, long after the ND individuals had pupated and died. Although most ND larvae pupated successfully, only 26% emerged at 7.5 krad and none at higher doses. The percentage of adult emergence was similar in D and ND lines, as was the greater sensitivity of females; but the emergence of D adults occurred a week later. The ND line had a greater adult mating success than the D line, and, at most doses a similar level of sterility. However, egg fertility was greater in the D line at all doses than in the ND line. Thus, diapausing larvae have limited value in a sterile insect release program because higher doses would be needed to sterilize D larvae than ND larvae, more somatic damage would occur, and less competitive adults would be produced.
Sustainable Development: A Better Holistic View

This article offers a critique of an article by Margrit Hugentobler that proposes a multi-systems level framework to guide sustainable development initiatives and evaluate completed projects. While praising Hugentobler's analysis of inadequacies with the United Nations' concept of sustainable development and her proposal for an integrative approach, this article raises concerns about the proposed framework's ability to equally achieve economic, environ- mental, and social objectives. As a better alternative, the author suggests a non-hierarchal, holistic framework. Moreover, this article contends that a sustainable development framework must include a focus on fair compensation and health and safety of workers.
Efficacy of Pt(Rh-123)2 as a radiosensitizer with fractionated X rays.

Abstract The complex of tetrachloroplatinate and rhodamine-123, Pt(Rh-123) 2 has demonstrated cytotoxic and antitumor effects and radio sensitizing potential in vitro and in vivo . Using the FSaIIC in vivo-in vitro tumor system, tumor cell survival indicated a dose modifying factor (DMF) of 1.51 due to the addition of Pt(Rh-123) 2 . Pt(Rh-123) 2 was added to two fractionated radiation protocols. The drug was administered by i.p. injection on three different multiple injection schedules, each reaching a cumulative dose of 75 mg/kg in those groups receiving the maximum treatment. Radiation was delivered in 3 Gy fractions in the morning and afternoon or daily for five days. Pt(Rh123) 2 was administered daily at 25 or I5 mg/kg or on alternate days at 25 mg/kg. The DMFs obtained ranged from 1.8 ± 0.2 to 1.25 ± 0.1. The pharmacokinetics of [ 195m Pt)-Pt(Rh-123) 2 after i.p. injection of 100 mg/kg of the drug were characterized in mice bearing the Lewis lung carcinoma using a two compartment model. The total exposure of the lung carcinoma to the drug as reflected by the area under the concentration vs. time curve was 1.5 times greater than that of the normal lung tissue. The formation of DNA cross-links and single strand breaks in SCC-25 cells exposed to Pt(Rh-123) 2 (100 μM and 6 Gy under normally oxygenated and hypoxic conditions immediately following treatment or 6 hours later were measured by DNA alkaline elution. Over the time course, the level of DNA cross-linking increased in the normally oxygenated cells by 1.5-fold and the hypoxic cells by 4-fold. The overall effects of Pt(Rh-123)2 in the presence of radiation results from both DNA cross-linking and single strand breaks.
Effect of fasting on nychthemeral concentrations of plasma growth hormone (GH), insulin-like growth factor I (IGF-I), and cortisol in channel catfish (Ictalurus punctatus).

Abstract This experiment was conducted to characterize the effect of fasting versus satiety feeding on plasma concentrations of GH, IGF-I, and cortisol over a nychthemeron. Channel catfish fingerlings were acclimated for two weeks under a 12L : 12D photoperiod, then fed or fasted for 21 d. On day 21, blood samples were collected every 2 h for 24 h. Weight of fed fish increased an average of 66.2% and fasted fish lost 21.7% of body weight on average. Average nychthemeral concentrations of plasma GH were not significantly different between fed (24.7 ng/mL) and fasted (26.8 ng/mL) fish, but average nychthemeral IGF-I concentrations were higher in fed (23.4 ng/mL) versus fasted (17.8 ng/mL) fish. An increase in plasma IGF-I concentrations was observed in fasted fish 2 h after a peak in plasma GH, but not in fed fish. Average nychthemeral plasma cortisol concentrations were higher in fed (14.5 ng/mL) versus fasted (11.0 ng/mL) fish after 21 d. Significant fluctuations and a postprandial increase in plasma cortisol were observed in fed fish and there was an overall increase in plasma cortisol of both fasted and fed fish during the scotophase. The present experiment indicates little or no effect of 21-d fasting on plasma GH levels but demonstrates fasting-induced suppression of plasma IGF-I and cortisol levels in channel catfish.
Ion interactions in calcium‐efficient and calcium‐inefficient tomato lines 1

Abstract Two Ca‐efficient and 3 Ca‐inefficient tomato lines selected on the basis of dry matter production, Ca concentrations in tissues, and severity of Ca deficiency symptoms were grown in nutrient solutions containing 6 levels of total Ca ranging from 15 to 365 mg in 70 mg increments. All lines responded to increased Ca supply by increasing in dry weight and by accumulating Ca. The critical Ca concentrations in the shoots were 0.25% and 0.40% on a dry weight basis for the efficient and inefficient lines, respectively. Concentrations of Ca, K, Mg, P, and NO3 ‐ were lower in shoots and except for Mg were lower in roots of efficient plants than in the inefficient plants. For all lines as more Ca was available in the media and as Ca increased in the shoots and roots, the concentrations of the nutrients other than Ca declined. The declines in concentrations of K and Mg were not due to dilution by higher dry matter production in the efficient lines relative to the inefficient ones, although the total accumul...
Phosphorus-31 nuclear magnetic resonance studies of the phosphonate and phosphate composition of the sea anemone, Bunadosoma, sp.

Abstract Advanced methods of 31P nuclear magnetic resonance spectroscopy were used in the analysis of the phosphonate and orthophosphate components of fractions from the sea anemone Bunadosoma sp. and in the analysis of hydrolyzates from these fractions. The spectra consist of cleanly separated phosphonate and orthophosphate resonance bands which have been interpreted in some detail. Analysis of the data showed that certain orthophosphates are resistant to classical hydrolytic procedures. These same hydrolytic procedures bring about chemical alterations of the phosphonate subunits which can affect the phosphonate to phosphate ratio as classically determined.
Fröhlich conduction in spin density waves and field induced spin density waves

We review the recent theory of phason dynamics in spin density waves in Bechgaard salts. The theoretical results on the threshold electric field, the nonOhmic conductivity and the microwave conductivity are compared to recent experimental results on spin density waves in Bechgaard salts.
Serotonin depolarizes cat spinal motoneurons in situ and decreases motoneuron afterhyperpolarizing potentials

Abstract Mechanisms by which serotonin produces a long duration facilitation of spinal motoneuron excitability were investigated in decerebrate cats using intracellular recording combined with extracellular microiontophoresis. Serotonin was found to produce a slowly developing, small amplitude, long duration depolarization of the spinal motoneurons. This finding conflicts with early reports of serotonin-induced rapid hyperpolarization of cat spinal motoneurons, but exactly corresponds to more recent findings in rat facial motoneurons. The depolarization was accompanied by an increase in motoneuron excitability and an increase in membrane input resistance. In addition, serotonin reduced the motoneuron postspike afterhyperpolarizing potential in several motoneurons even though depolarization consistently occurred.
Catecholamine metabolite excretion of infants with heart failure.

Twenty-four hour excretion of the catecholamine metabolites, normetanephrine and metanephrine (NMN+MN) and vanillyl-mandelic acid (VMA), was found to be elevated more than twofold in infants with severe heart failure, probably indicating augmented catecholamine biosynthesis. The role of catecholamines in the pathophysiology of heart failure is discussed. Infants with severe cyanosis rather than heart failure as the major problem showed a minor increase of NMN+MN excretion but not of VMA excretion.
Thermophysical properties of molybdenum and rhenium

Thermophysical properties measurements have been made on the metals molybdenum and rhenium at high temperatures and a pressure of 0.2 GPa. These measured properties include volume, temperature, enthalpy, and electrical resistivity. Values for these quantities are shown for both solid and liquid phases. In addition, sound velocities were measured for liquid molybdenum.
Microscopic determination of optical and electronic properties of ultrathin passive layers by photocurrent measurements with single grains as an example

Abstract Different photoelectrochemical methods such as photocurrent spectroscopy, uv-laser transient and locodynamic uv-laser scanning experiments were carried out to characterize the Ti TiO 2 system. All measurements were carried out at high local resolution of Ti single grains of known crystallographic orientation. The experimental findings clearly prove that the Gartner/Butler model is insufficient for description of the i ph ( d lay ) and i ph ( U ) behaviour of ultrathin amorphous TiO 2 films. Both the effect of multiple internal reflections and the influence of the recombination efficiency r ( E ) must be considered. For this, a complete model is presented and discussed. Consideration of all three parts of this model (Gartner, optics r ( E )) allows for a complete interpretation of the experimental findings enabling determination of both electronic and optical layer properties. Both the optical (refractive index, absorption coefficient) and the electronic layer properties (defect state density N D and permittivity number ϵ(0) show a significant dependence on the orientation of the substrate grains.
Improving weather and climate prediction with the AIRS on Aqua

The Atmospheric Infrared Sounder (AIRS) on the EOS Aqua Spacecraft was launched on May 4, 2002. Early in the mission, the AIRS instrument demonstrated its value to the weather forecasting community with better than 6 hours of improvement on the 5 day forecast. Now with over six years of consistent and stable data from AIRS, scientists are able to examine processes governing weather and climate and look at seasonal and interannual trends from the AIRS data with high statistical confidence. Naturally, long-term climate trends require a longer data set, but indications are that the Aqua spacecraft and the AIRS instrument should last beyond 2016. This paper briefly describes the AIRS products, reviews past science and weather accomplishments from AIRS data product users and highlights recent findings in these areas.
Thermal reactions of N,N′ bis(p‐nitrophenyl)sulfamide and p‐benzoquinone dioxime–acid mixtures

N,N′ Bis(p-nitrophenyl)sulfamide and p-benzoquinone dioxime–acid mixtures were found to undergo an abrupt reaction when heated to give a black polymeric material. These polymeric materials exhibited thermal stability (TGA in N2) up to 500°C and were insoluble in all solvents including hot concentrated sulfuric acid. From analytical data, structural formulae have been assigned to the polymeric materials that are logically derivable from the starting materials.
Etiogenesis of the European cystic fibrosis polymorphism: heterozygote advantage against venereal syphilis?

Abstract Cystic fibrosis (CF) in European Caucasians is a balanced polymorphism, presumably associated with some sort of heterozygote advantage. In the 16th century, venereal syphilis was present in Europe in the general area of the CF polymorphism; it was not present in other parts of the world, and no other fatal disease had this localization. Historical and geographic considerations therefore suggest that the CF polymorphism formed as a result of protective advantage against venereal syphilis.
Finite amplitude disturbances in a rotating fluid

A liquid is rotating with angular velocity vector along the z -axis. A uniform gravity field acts along the negative z -axis and the liquid is stratified with arbitrary density gradient. A steady disturbance exists with all properties independent of one of the horizontal coordinates, say, y . It is then shown that the primitive equations can be integrated once to yield a second-order vorticity equation. This equation is generally non-linear and complicated but greatly simplifies when the fluid is homogeneous. In one special and interesting case the problem becomes identical to two-dimensional flow of a certain stratified fluid in a uniform gravity field. DOI: 10.1111/j.2153-3490.1971.tb00548.x
ATRIAL NATRIURETIC FACTOR RECEPTOR GUANYLATE CYCLASE SIGNALING: NEW ATP- REGULATED TRANSDUCTION MOTIF

ANF-RGC membrane guanylate cyclase is the receptor for the hypotensive peptide hormones, atrial natriuretic factor (ANF) and type B natriuretic peptide (BNP). It is a single transmembrane spanning protein. Binding the hormone to the extracellular domain activates its intracellular catalytic domain. This results in accelerated production of cyclic GMP, a second messenger in controlling blood pressure, cardiac vasculature, and fluid secretion. ATP is the obligatory transducer of the ANF signal. It works through its ATP regulated module, ARM, which is juxtaposed to the C-terminal side of the transmembrane domain. Upon interaction, ATP induces a cascade of temporal and spatial changes in the ARM, which, finally, result in activation of the catalytic module. Although the exact nature and the details of these changes are not known, some of these have been stereographed in the simulated three-dimensional model of the ARM and validated biochemically. Through comprehensive techniques of steady state, time-resolved tryptophan fluorescence and Forster Resonance Energy Transfer (FRET), site-directed and deletion-mutagenesis, and reconstitution, the present study validates and explains the mechanism of the model-based predicted transduction role of the ARM’s structural motif, 669WTAPELL675. This motif is critical in the ATP-dependent ANF signaling. Molecular modeling shows that ATP binding exposes the 669WTAPELL675 motif, the exposure, in turn, facilitates its interaction and activation of the catalytic module. These principles of the model have been experimentally validated. This knowledge brings us a step closer to our understanding of the mechanism by which the ATP-dependent spatial changes within the ARM cause ANF signaling of ANF-RGC.
Cell Cycle Checkpoints: Preventing an Identity Crisis

Cell cycle checkpoints are regulatory pathways that control the order and timing of cell cycle transitions and ensure that critical events such as DNA replication and chromosome segregation are completed with high fidelity. In addition, checkpoints respond to damage by arresting the cell cycle to provide time for repair and by inducing transcription of genes that facilitate repair. Checkpoint loss results in genomic instability and has been implicated in the evolution of normal cells into cancer cells. Recent advances have revealed signal transduction pathways that transmit checkpoint signals in response to DNA damage, replication blocks, and spindle damage. Checkpoint pathways have components shared among all eukaryotes, underscoring the conservation of cell cycle regulatory machinery.
Experimental coronary artery occlusion: ventricular fibrillation and survival as affected by selected drugs and ionic alterations.

SUMMARY 1.The effect of selected drugs and various inorganic ions on ventricular fibrillation and mortality following experimental coronary artery occlusion has been investigated. 2.Control mortality of 80 per cent and early fibrillation of 30 per cent was obtained following ligation of the left anterior descending coronary artery immediately at its origin. 3.When coronary occlusion was delayed for 20 days post-pericardotomy in three animals there was no mortality and two of the three animals failed to demonstrate any change in the pre and postocclusion electrocardiogram. 4.Mortality of 80 per cent and fibrillation of 40 per cent resulted when acidosis was produced by hydrochloric acid. 5.Mortality of 80 per cent and fibrillation of 60 per cent resulted when alkalosis was produced by the infusion of sodium bicarbonate. 6.A mortality rate of 60 per cent and a fibrillation rate of 60 per cent resulted when hyperkaliemia was produced. 7.Hypercalcemia produced a mortality of 80 per cent and fibrillation of 60 per cent. 8.Following the infusion of a relatively small amount of sodium chloride an unexpected 100 per cent mortality and 80 per cent fibrillation rate resulted. 9.A mortality rate of 100 per cent and a fibrillation rate of 100 per cent followed the infusion of procaine. 10.The intravenous administration of papaverine produced mortality and fibrillation rates of 60 per cent. 11.Quinidine administered intravenously yielded a mortality rate of 60 per cent and fibrillation rate of 60 per cent. 12.The influence of infusion of certain ions and drugs upon the concentration of other ions was determined. 13.It would appear from this study that if potassium is the excitatory agent for ventricular fibrillation that myocardial potassium in ischemia is unaffected by the plasma concentration of potassium and is on a metabolic basis. 14.If potassium is the agent inciting ventricular fibrillation it would appear from this study that myocardial metabolism of potassium in myocardial ischemia is unaffected by blood pH insofar as decreasing early fibrillation is concerned. 15.None of the drugs or ions employed in this study showed any beneficial effect on reducing mortality or ventricular fibrillation following coronary artery occlusion. We gratefully acknowledge the electrocardiographic interpretation of Dr. Thomas M. Blake.
Central Place Models of Acorn and Mussel Processing

We use a central place foraging model of field resource processing to explore the archaeological implications of experimental and ethnographical observations pertaining to the collection and processing of black oak (Quercus kelloggii) and big mussel (Mytilus californianus). These data suggest oak field processing will generally be minimal and confined mainly to drying and that big mussel may be transported unprocessed or completely processed depending on round-trip travel time and mussel colony productivity. Archaeological data further demonstrate that the field processing of mussels is frequently at odds with central place model predictions, suggesting optimization of quantities other than calories and time.
Superconductivity in the Sr-Ca-Cu-O system and the phase with infinite-layer structure

Superconductivity and structure in samples of (Sr,Ca)${\mathrm{CuO}}_{2}$ with the infinite-layer structure, prepared by high-pressure synthesis, have been studied using magnetic susceptibility measurements, small angle x-ray diffraction, and neutron diffraction. It is found that the superconducting (${\mathit{T}}_{\mathit{c}}$\ensuremath{\sim}100 K) samples in this system are phase impure and contain, in addition to the infinite-layer phase, members of the two homologous series ${\mathrm{Sr}}_{\mathit{n}\mathrm{\ensuremath{-}}1}$${\mathrm{Cu}}_{\mathit{n}+1}$${\mathrm{O}}_{2\mathit{n}}$ (n=3,5,...; orthorhombic), and ${\mathrm{Sr}}_{\mathit{n}+1}$${\mathrm{Cu}}_{\mathit{n}}$${\mathrm{O}}_{2\mathit{n}+1+\mathrm{\ensuremath{\delta}}}$ (n=1,2,...; tetragonal), as minor phases. Samples with larger phase fractions of the ${\mathrm{Sr}}_{\mathit{n}+1}$${\mathrm{Cu}}_{\mathit{n}}$${\mathrm{O}}_{2\mathit{n}+1+\mathrm{\ensuremath{\delta}}}$ compounds showed higher superconducting fractions. Phase-pure infinite-layer samples are not superconducting. Based on these results, and results previously published in the literature, it is proposed that the superconductivity in these infinite-layer samples comes from the tetragonal ${\mathrm{Sr}}_{\mathit{n}+1}$${\mathrm{Cu}}_{\mathit{n}}$${\mathrm{O}}_{2\mathit{n}+1+\mathrm{\ensuremath{\delta}}}$ compounds, not from the phase with the infinite-layer structure.
Error characteristics of ad hoc positioning systems (aps)

APS algorithms use the basic idea of distance vector routing to find positions in an ad hoc network using only a fraction of landmarks, for example GPS enabled nodes. All the nodes in the network are assumed to have the possibility of measuring: range, angle of arrival (AOA), orientation, or a combination of them. We give a lower bound for positioning error in a multihop network for a range/angle free algorithm, and examine the error characteristic of four classes of multihop APS algorithms under various condition, using theoretical analysis and simulations. Analysis of range/angle free, range based, angle based, and multimodal algorithms show a complex tradeoff between the capabilities used, the density of the network, ratio of landmarks, and the quality of the position obtained.
Partial Purification and Properties of l-Glutamine d-Fructose 6-Phosphate Amidotransferase from Phaseolus aureus.

l-Glutamine d-fructose 6-phosphate amidotransferase (EC 2.6.1.16) was extracted and purified 600-fold by acetone fractionation and diethylaminoethyl cellulose column chromatography from mung bean seeds (Phaseolus aureus). The partially purified enzyme was highly specific for l-glutamine as an amide nitrogen donor, and l-asparagine could not replace it. The enzyme showed a pH optimum in the range of 6.2 to 6.7 in phosphate buffer. Km values of 3.8 mm and 0.5 mm were obtained for d-fructose 6-phosphate and l-glutamine, respectively. The enzyme was competitively inhibited with respect to d-fructose 6-phosphate by uridine diphosphate-N-acetyl-d-glucosamine which had a Ki value of 13 μm. Upon removal of l-glutamine and its replacement by d-fructose 6-phosphate and storage over liquid nitrogen, the enzyme was completely desensitized to inhibition by uridine diphosphate-N-acetyl-d-glucosamine. This indicates that the inhibitor site is distinct from the catalytic site and that uridine diphosphate-N-acetyl-d-glucosamine acts as a feedback inhibitor of the enzyme.
Growth factor regulation of growth factors in articular chondrocytes.

Several lines of evidence indicate that polypeptide growth factors are important in articular cartilage homeostasis and repair. It is not yet clear how these growth factors are regulated. We tested the hypothesis that the growth factors responsible for regulating cartilage are themselves regulated by growth factors. We delivered insulin-like growth factor I (IGF-I), fibroblast growth factor-2 (FGF-2), and/or transforming growth factor-β1 (TGF-β1) to adult bovine articular chondrocytes in primary culture and measured the resulting changes in IGF-I, FGF-2, and TGF-β1 gene expression and protein production. These growth factors differentially regulated their own and each others gene expression and protein production. In concert, they regulated each other in an interactive fashion. Their interactions ranged from inhibitory to synergistic. The time course of the regulatory effects differed among the individual growth factors and combinations. Growth factor-induced changes in growth factor protein production by articular chondrocytes generally corresponded to the changes in gene expression patterns. These studies suggest that interactions among IGF-I, FGF-2, and TGF-β1 substantially modulate their regulatory functions. The results may help guide the application of growth factors to articular cartilage repair.
Liquid-metal electrode to enable ultra-low temperature sodium–beta alumina batteries for renewable energy storage

Sodium–beta alumina batteries often need high operating temperatures, and one of the reasons is poor wettability of liquid sodium on the surface of beta alumina. Here, Lu et al. report an alloying strategy that improves the wettability, allowing the batteries to be operated at much lower temperatures.
The United Nations Basic Space Science Initiative for IHY 2007

The United Nations Office for Outer Space Affairs and the International Heliophysical Year (IHY) community have joined hands to deploy arrays of small, inexpensive instruments such as magnetometers, radio telescopes, GPS receivers, all-sky cameras, and particle detectors around the world to provide global measurements of ionospheric, magnetospheric and heliospheric phenomena. The small instrument programme is envisioned as a partnership between instrument providers, and instrument hosts in developing countries as one of United Nations Basic Space Science (UNBSS) activity. The lead scientist will provide the instruments (or fabrication plans for instruments) in the array; the host country will provide manpower, facilities, and operational support to obtain data with the instrument, located typically at a local university. This paper provides an overview of the IHY/UNBSS programme, its achievements and
A Moving Horizon Estimator for processes with multi-rate measurements: A Nonlinear Programming sensitivity approach

Abstract Moving Horizon Estimation (MHE) provides a framework that allows one to incorporate both frequent and infrequent observations easily because it uses a window of past measurements, where the slower ones can be introduced as they become available. Also, MHE allows for the use of constraints on the state estimates, which improves the performance of the estimator. Here we propose the use of a variable structure MHE that can handle multi-rate measurements. Furthermore, we propose a novel strategy for updating the smoothed covariance matrix of the arrival cost based on Nonlinear Programming (NLP) sensitivity. For this we show the relationship that exists between the covariance and the reduced Hessian of the NLP. Moreover, we propose a fast strategy for extracting the reduced Hessian information directly from the linearized optimality conditions used in Interior Point solvers such as IPOPT. The proposed methodology is illustrated using benchmark examples from the literature.
Continuous and Poisson-distributed costs accumulated within a stationary Markov process

Abstract The continuous time Markov process with s transient and r absorbing states is introduced with parameter estimation from longitudinal data. A cost structure is then superimposed on each transient state, distinguishing between the uniform cost rate and discrete Poisson costs. Through the cumulative cost expectations, populations variances between durations of stay, and asymptotic sample convariances between durations of stay, expressions are derived for both stochastic and estimation variances of the cost function. A numerical example is presented, without and with Poisson costs, and comparisons made between stochastic and estimation error.
Fiber-optic 200-Mbit local area network

The use of fiber optics in high-capacity local area networks introduces some special concerns not found in point-to-point data transmission systems. These concerns include fast response to burst mode data, minimizing background light from nonoperating transmitters, wide dynamic range in receivers and efficient data coding, and protocols for high-bit-rate operation. We describe a network system for 200-Mbit/sec operation that incorporates novel opto-electronic and system designs which address these concerns.
Guidelines for Drug Education Through Electronic Media.

Most effective drug education through electronic media appears likely when delivered through television by a person considered knowledgeable, or important by viewers, and with whom they can identify. Content should be educational with minimum fear aroused. Some discomfort (but not too much) to the listener, plus suggestions for alternate socially acceptable behavior appear likely to cause behavior change.
Rollover Threshold of Partially Filled Tank Vehicles with Arbitrary Tank Geometry

Rollover threshold limits of partially filled tank vehicles equipped with tanks of arbitrary cross-sections are estimated using a simple methodology. Overturning moment caused by the lateral liquid...
Kinetic effects of urea on the activation of aged glycogen phosphorylase a by adenosine 5′-phosphate

Abstract Previous observations have indicated that the sigmoid curve of rate versus Pi concentration obtained with aged preparations of phosphorylase a (a-1,4-glucan; orthophosphate glucosyltransferase, EC 2.4.1.1), is abolished by the activator AMP. The effects of urea on the kinetics of the enzymatic reaction were investigated in order to help clarify the relationship between structure and function. Urea also abolished the sigmoid curve although at concentrations 10 000-fold higher than AMP. However, although 2·10-5M AMP reduced the apparent Km for Pi, 0.3 M urea was a competitive inhibitor with respect to Pi, and 1.0 M urea caused inhibition of the mixed type. Mixed inhibition experiments with urea and arsenate, a true competitor of Pi, and the reduction of the Km for AMP by both urea and arsenate indicated that urea indeed competed with Pi. Urea did not affect the V for AMP, whereas arsenate reduced it. The data indicated that AMP protected the enzyme against urea inhibition by reducing the affinity of the enzyme for urea. It is suggested that aging causes changes in the structure of the enzyme which allow easier demontration of homotropic interactions.
Unusual presentation and course of acute cardiac tamponade.

CUTE CARDIAC TAMPONADE is a life-threatening medical condition. The rate of accumulation of fluid in the pericardial space is a major determinant of presenting signs and symptoms. The restrictive tamponade effect of rapidly accumulating fluid around the heart causes a myriad of clinical consequences including decreased stroke volume, hypotension with compensatory tachycardia, and a heart rate-dependent cardiac output. The authors present a case of an acute cardiac tamponade in which most of the classic signs and symptoms were absent. CASE REPORT An otherwise healthy 56-year-old patient with a history of ocular melanoma presented to the radiology suite to undergo a liver biopsy under computed tomography (CT) guidance. Past medical history was negative; the patient was not taking any medications other than vitamins and had no known drug allergies. The patient had a solitary lesion in the left lobe of the liver adjacent to the inferior vena cava and anterior to the right hepatic vein. Vital signs were monitored throughout the procedure via an automated blood pressure cuff, electrocardiography, and pulse oximetry, and supplemental oxygen was administered via a nasal cannula. After the administration of adequate intravenous sedation and skin infiltration with local anesthetics, a 22-G Franseen biopsy needle was inserted. The initial pass of the needle showed its entry at the superior aspect of the liver at a depth of 11 cm with poor visualization of the distal tip. The needle was withdrawn and repositioned lateral and inferior to the lesion. During the procedure, the patient started complaining of nausea, and then over the next few minutes the radiologist noticed that the patient became rigid, appearing almost like having a seizure. Meanwhile, the patient’s heart rate dropped precipitously from a previous range of 70 to 80 beats/min to 45 to 50 beats/min in a sinus bradycardia, and the patient appeared to be unresponsive. The biopsy needle was immediately withdrawn, the procedure aborted, and attention was focused on patient resuscitation. The patient’s airway was supported by chin lift, and spontaneous respiratory efforts were assisted by administration of oxygen and positive-pressure ventilation via a resuscitation bag-mask device. The administration of a fluid bolus was effective in the treatment of hypotension, and the patient’s heart rate returned to baseline values without pharmacologic intervention. The patient was responsive and oriented but continued to complain of nausea that was not relieved despite the administration of 10 mg of metoclopramide.