cssi/SciSciGPT-SciSciNet huggingface dataset:
A general approach for the design and isolation of protein fragments: The molecular dissection of dihydrofolate reductase

Publisher Summary This chapter describes a combination of chemical cleavage and affinity chromatography that can be used to produce large quantities of protein fragments that vary considerably in size, stability, and solubility. The ability to cleave proteins into specific fragments is a powerful tool for probing complex sequence/structure/function relationships that occur in protein folding, protein–protein interactions, and enzyme activity. The approach utilizes alkaline catalyzed cleavage following cyanylation of cysteine residues by 2-nitro-5-thiocyanobenzoic acid (NTCB). Cysteine-specific cleavage reagents are attractive because of the relatively unique reactivity of cysteines and the scarcity of free cysteines in many proteins. Immobilized metal affinity chromatography (IMAC) has proved to be a versatile and specific technique for the purification of poly-histidine tagged fusion proteins, and can be used under strongly denaturing conditions to isolate the resulting fragments. The application of this approach to dihydrofolate reductase from Escherichia coli reveals that several large fragments that correspond to observed structural domains, adopt significant secondary structure in solution. These fragments contain sufficient information to act as autonomous folding units and may provide clues to the structures of transient folding intermediates.
DNA binding specificity and sequence of Xanthomonas campestris catabolite gene activator protein-like protein.

The Xanthomonas campestris catabolite gene activator protein-like protein (CLP) can substitute for the Escherichia coli catabolite gene activator protein (CAP) in transcription activation at the lac promoter (V. de Crecy-Lagard, P. Glaser, P. Lejeune, O. Sismeiro, C. Barber, M. Daniels, and A. Danchin, J. Bacteriol. 172:5877-5883, 1990). We show that CLP has the same DNA binding specificity as CAP at positions 5, 6, and 7 of the DNA half site. In addition, we show that the amino acids at positions 1 and 2 of the recognition helix of CLP are identical to the amino acids at positions 1 and 2 of the recognition helix of CAP:i.e., Arg at position 1 and Glu at position 2.
An adaptive receiver for frequency selective fading channels

Adaptive reception of binary data over a frequency selective slow Rayleigh fading communication channel, through wideband signaling, using spectral spreading codes is considered. Based on the likelihood ratio test, an estimator correlator receiver structure is developed. The receiver structure includes the effects of estimation errors, which are usually neglected. The estimator is a Wiener-Hopf filter, and for reasonable SNRs the estimator can be realized as simple linear averaging, which is asymptotically optimal. In practice, the linear averaging may have to be modified by using exponential weights to prevent runaway due to decision errors. The receiver performance is a function of estimation error variance, which depends on the channel SNR, multipath spread and profile, fade rate, and multiuser interference, when used for SSMA (satellite-switched multiaccess) applications. >
Einstein Relation for a Tagged Particle in Simple Exclusion Processes

It is known that the rescaled position of a tagged particle in symmetric simple exclusion processes converges to a diffusion. If now the tracer particle is driven by a small force, then it picks up a velocity. The Einstein relation states that in the limit, this velocity is proportional to the small force, and the constant of proportionality can be computed from the diffusion matrix of the tracer particle with no driving force. Such a relation is believed to be generally valid. In this article we establish its validity for all symmetric simple exclusion processes in dimension \(\) and we prove a density property for certain invariant states of the driven system.
A Model Inquiry-Based Genetics Experiment for Introductory Biology Students: Screening for Enhancers & Suppressors of Ptpmeg

Abstract It has been noted that undergraduate project-based laboratories lead to increased interest in scientific research and student understanding of biological concepts. We created a novel, inquiry-based, multiweek genetics research project studying Ptpmeg, for the Introductory Biology Laboratory course at Brandeis University. Ptpmeg is a protein involved in axon formation in Drosophila melanogaster. In order to better understand Ptpmeg's functionality, students sought to find Ptpmeg's enhancers and suppressors by engaging in either a 4- or a 7-week modular research project. By the end of the semester, students were able to learn various laboratory techniques and acquire a deeper understanding of Drosophila genetics in both versions of the course.
A PAN analog from isoprene photooxidation

Peroxymethacrylic nitric anhydride (MPAN), a potential atmospheric photoproduct, was synthesized and characterized in the laboratory for the first time. The compound was identified by FT-IR, GC-MS, GC/ECD, and decomposition studies. Purification of synthetic mixtures provided a sample suitable for calibration of instruments for ambient atmospheric sampling. Possible field identification of MPAN is reported, and the role of MPAN in the chemistry of the rural troposphere is discussed.
A Grounded Theory of Balancing Alcohol Recovery and Pregnancy

The purpose of this study was to explore women's concurrent experiences of alcohol/drug recovery and transition to parenthood. The study used a qualitative design to explore and understand women's experiences of recovery from alcohol/drug dependence during pregnancy. Eleven women, who self-identified as recovering alcoholics/addicts and either were pregnant or had infants younger than 12 months of age, participated in the study. Balancing emerged as the core concept, a process that explained how women successfully integrated the recovery and motherhood processes into their identity. The women used strategies learned in the process of alcohol/drug recovery to balance between alcohol/drug recovery and motherhood. They used the strategies in unique ways during pregnancy to incorporate the developmental and relational aspects of both advancing in motherhood and maintaining recovery.
Between-word processes in child phonology.

Most processes in child phonology have as their domain a single word or a smaller chunk of phonological material. Processes that involve the interaction of two or more words have never been examined. In a diary study of the speech of one child acquiring English, there were eight between-word processes. All were optional and occurred in fairly restricted environments. Most of the processes were of short duration. Consequences for the study of child phonology are discussed.
Purification and characterization of thiols in an arsenic hyperaccumulator under arsenic exposure.

Pteris vittata (Chinese brake fern) is the first reported arsenic hyperaccumulator. To investigate the arsenic tolerance mechanism in this plant, reversed-phase HPLC with postcolumn derivatization was used to analyze the thiols induced under arsenic exposure. A major thiol in the plant leaflets was found to be responsive to arsenic exposure. The arsenic-induced compound was purified on a large scale by combining covalent chromatography and preparative reversed-phase HPLC. About 2 mg of this compound was isolated from 1 kg of fresh leaflets. The purified arsenic-induced compound was characterized using electrospray ionization mass spectrometry. A molecular ion (M + 1) of 540 and fragments were obtained, which indicated that the arsenic-induced thiol was a phytochelatin with two subunits (PC2). Compared to the classical methods for purification of phytochelatins, this new method is more specific, simple, and rapid and is suitable for purification of PCs in a large scale as well as sample preparation for mas...
Saturated and mono-unsaturated long-chain hydrocarbons from lemon juice sacs

Abstract Three varieties of lemon—Lisbon, Malta and Kusner—were examined for their content of juice sac saturated and mono-unsaturated long-chain hydrocarbons. The saturated fractions were 20 times the concentrations of the monoene fractions. The dominant linear hydrocarbon in the saturated fraction was C 25 while C 29 predominated in the monoene fraction. The saturated hydrocarbon profiles for Lisbon and Kusner were very similar to the profiles previously reported for Eureka lemon and Persian lime. The mono-unsaturated profiles were distinct for each of the three lemon varieties. In addition the lemon mono-unsaturated profiles were quite distinct from the hydrocarbon profiles previously reported for several other citrus species. In general the data support the elongation-decarboxylation mechanism for hydrocarbon synthesis proposed by Kolattukudy.
The role of training in global tobacco control research

Despite the pandemic nature of the tobacco control problem, little attention has been given to the role of research training in stemming the global tide of tobacco use. Tobacco research plays a critical role in both shaping policy and saving lives, and training new tobacco researchers is an important part of the tobacco control agenda. There are several conceptual training models, all of which emphasize communicative partnerships and multidisciplinary approaches. It also is important to take cultural background and specificity into account when shaping research and training agendas. We present a number of successful training initia
Measurement of the aerosol component of the modulation transfer function in desert atmospheres

A unique experimental technique has made it possible to make measurements in desert atmospheres of the horizontal modulation transfer function (MTFA) and its components which are attributed to contrast, aerosols, and turbulence. In particular, use of this technique has made it possible, for the first time, to directly measure the low spatial frequency cutoff of the aerosol component. This technique is based on utilizing digital image processing of remote video scenes that include two, optically identical, castellated targets which are located at different distances and are contrasted against the horizon sky. Ratios of contrast and FFT calculations may be used to determine the absolute values and spatial cutoff frequencies of the MTFA and its three components, independent of the imaging system and actual properties of the targets. The experimental technique is described along with preliminary MTFA measurements of the aerosol component.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Deterrence of Methaqualone Abuse through Mass Urinalysis

A temporary court-ordered cessation of urine testing in Europe and the widespread abuse of a detectable methaqualonecontaining drug provided an opportunity with the resumption of testing for the evaluation of the possible effects of urinalysis on usage patterns. Evidence is presented suggesting that in this instance urinalysis acted to deter usage of this particular drug.
Toluene removal in membrane bioreactors under recirculating and non-recirculating liquid conditions

A single-, dual- and multiple-tube dense phase silicone rubber membrane bioreactor were investigated for control of toluene-contaminated air under circulating and non-recirculating liquid conditions. A mathematical model was developed to describe the system. The reactors were seeded with a mixed bacterial consortium isolated from activated sludge and capable of aromatic biodegradation. After operating with recirculating liquid nutrient solution, the reactors were operated with no recirculation of the liquid, for 50 days or more in each instance. Average toluene removal measured in the single-tube reactor was 93 ppm with recirculating liquid and 102 ppm without recirculation of the liquid. Average removal measured in the dual-tube reactor was 396 ppm with recirculating liquid and 319 ppm without recirculation of the liquid. Operation under stagnant liquid conditions had no significant detrimental impact on bioreactor performance. Biokinetic parameters were measured for both the suspension and biofilm with values of the maximum specific utilization rate values (k) ranging from 0.01 to 0.42 h−1 and half saturation constant values (K S) ranging from 1.5 to 14.3 mg L−1. Results suggest that membrane bioreactors might be operated under non-recirculating liquid conditions without performance detriment, reducing or eliminating the energy requirements and costs associated with pump operation.
On the fracture toughness of ferroelastic materials

The toughness enhancement due to domain switching near a steadily growing crack in a ferroelastic material is analyzed. The constitutive response of the material is taken to be characteristic of a polycrystalline sample assembled from randomly oriented tetragonal single crystal grains. The constitutive law accounts for the strain saturation, asymmetry in tension versus compression, Bauschinger effects, reverse switching, and strain reorientation that can occur in these materials due to the non-proportional loading that arises near a propagating crack. Crack growth is assumed to proceed at a critical level of the crack tip energy release rate. Detailed finite element calculations are carried out to determine the stress and strain fields near the growing tip, and the ratio of the far field applied energy release rate to the crack tip energy release rate. The results of the finite element calculations are then compared to analytical models that assume the linear isotropic K-field solution holds for either the near tip stress or strain field. Ultimately, the model is able to account for the experimentally observed toughness enhancement in ferroelastic ceramics.
Demand Uncertainty and the Bayesian Effect in Markdown Pricing with Strategic Customers

This paper studies the role of demand uncertainty in temporal discrimination when the retailer applies markdown pricing facing strategic customers. We consider a model in which a retail firm announces a pair of declining prices for two selling periods, and customers with heterogeneous valuations each decide whether to buy a unit early, later or never. In this model, if the demand function is linear and its parameters are common knowledge, there never exist any markdown prices that achieve temporal discrimination for any feasible model parameters. Either all buying customers wait, or all buy early. By contrast, if the demand level is unknown, there always exists a temporally discriminating markdown pricing scheme for all feasible model parameters. We derive qualitative insights to the way demand uncertainty and Bayesian updating contribute to temporal discrimination, which broadly apply to nonlinear demand functions as well. We also show that in case of demand uncertainty, there always exists a temporally ...
Ligands for the Peroxisome Proliferator-Activated Receptor-γ and the Retinoid X Receptor-α Exert Synergistic Antiproliferative Effects on Human Coronary Artery Smooth Muscle Cells

Abstract In human coronary artery vascular smooth muscle (hcaVSM) cells, the mechanisms that mediate the antiproliferative effects of ligands for the peroxisome proliferator-activated receptor-γ (PPARγ) and the retinoid X receptor-α (RXRα) are unclear. Dimerization of PPARγ with RXRα and occupancy by both ligands is required for maximal activation. Accordingly, we determined whether the antiproliferative activity of the PPARγ ligands, troglitazone or 15-deoxy-Δ-12,14-prostaglandin J2 (15d-PGJ2), was enhanced with the RXRα ligand, 9-cis-retinoic acid (9-cis-RA). Incubation of actively proliferating hcaVSM cells with either troglitazone or 15d-PGJ2 resulted in a dose-dependent inhibition of proliferation with half-maximal inhibitory concentrations (IC50s) of 13 and 2 μM, respectively. Quiescent cells incubated with troglitazone or 15d-PGJ2 and subsequently stimulated with PDGF-BB showed a concentration-dependent decrease in the active form of MAP kinase, suggesting that inhibition of cell growth by troglitazone may involve the MAP kinase pathway, an important growth activation pathway in VSM cells. Incubation of cells with either 0.1 or 1.0 μM 9-cis-RA inhibited cell growth to a similar degree. Addition of troglitazone or 15d-PGJ2 to cells in combination with either concentration of 9-cis-RA resulted in a striking increase in growth inhibition, and was accompanied by an approximately 4-fold reduction in the IC50s for both PPARγ ligands. These findings imply that RXRα activation by 9-cis-RA synergistically enhanced inhibition of hcaVSM cell growth. The precise nature of this cooperative interaction between PPARγ and RXRα remains to be determined.
The plastic box -- a 4π detector for intermediate energy heavy ion physics

A 4π array of plastic scintillator has been constructed and used in conjunction with high resolution solid state detectors. The array is employed principally to discriminate multinucleon transfer reactions from three-body (or more) final states. It should be useful for a broad class of experiments in which a global charged particle anticoincidence is required.
Effects of protein stability and structure on substrate processing by the ClpXP unfolding and degradation machine

ClpXP is an ATP‐dependent protease that denatures native proteins and translocates the denatured polypeptide into an interior peptidase chamber for degradation. To address the mechanism of these processes, Arc repressor variants with dramatically different stabilities and unfolding half‐lives varying from months to seconds were targeted to ClpXP by addition of the ssrA degradation tag. Remarkably, ClpXP degraded each variant at a very similar rate and hydrolyzed ∼150 molecules of ATP for each molecule of substrate degraded. The hyperstable substrates did, however, slow the ClpXP ATPase cycle. These results confirm that ClpXP uses an active mechanism to denature its substrates, probably one that applies mechanical force to the native structure. Furthermore, the data suggest that denaturation is inherently inefficient or that significant levels of ATP hydrolysis are required for other reaction steps. ClpXP degraded disulfide‐cross‐linked dimers efficiently, even when just one subunit contained an ssrA tag. This result indicates that the pore through which denatured proteins enter the proteolytic chamber must be large enough to accommodate simultaneous passage of two or three polypeptide chains.
The association between childhood asthma prevalence and monitored air pollutants in metropolitan areas, United States, 2001-2004.

Background Air pollution exposure has been linked to adverse respiratory health outcomes among children, primarily in studies of acute exposures that are often in limited geographic areas. We sought to assess the association between chronic outdoor air pollution exposure, as measured by 12-month averages by county, and asthma among children in metropolitan areas across the nation.
Conflict and control: Examining the association between exposure to television portraying interpersonal conflict and the use of controlling behaviors in romantic relationships.

Based on content analyses examining the type and amount of relational conflicts featured in popular television (Brinson, 1992; Brinson & Winn, 1997; Comstock & Strzyzewski, 1990; Fine, 1981; Greenberg, Buerkel-Rothfuss, Neuendorf, & Atkin, 1980; Sherry & De Souza, 2005), the present study investigated the link between exposure to television that is high in interpersonal conflict and viewers' use of relational control in their romantic relationships. The results demonstrate a small but statistically significant relationship between exposure to interpersonal-conflict television and relational control, even after controlling for demographic, relationship, and personality variables. Further, the results demonstrate that the main relationship was moderated by viewers' perceived realism of television. Theoretical implications are discussed.
CCA-II: An improved system for emission computed tomography (ECT)

Abstract In a previous paper we presented the results of a computer study of a gh resolution, high sensitivity, three-dimensional imaging system for nuclear medicine (CCA). It was concluded that the system was not clinically practical because of the need for recalibration for every patient and the possibly large amounts of computer time needed to reconstruct the images. By redesigning the (simulated) hardware and software, both of these objections have now been overcome, while retaining the most important CCA advantages. The system's salient features are: (1) tomogrphic and/or full three-dimensional images, (2) very large geometric acceptance, (3) image cell sizes as small as 1 mm, (4) gamma rays of any energy can be used, (5) standard deviations are calculated for the activity in each image cell enabling the statistical significance of any image feature to be determined.
Strong field evidence of directional permeability scale effect in fractured rock

Permeability is a key parameter that controls mass and energy transport in geologic media. Its spatial variation is generally agreed within the research community, while the scale effect in permeability is still under considerable debate. This debate is mainly due to the lack of consistent measurement and interpretation of site data. Here, we show a strong field evidence of directional permeability scale effect from cross-hole pneumatic injection tests conducted in unsaturated fractured tuff at a field site in central Arizona, USA. The analysis reveals that permeability increases with the radial distance measured between the centroids of injection and monitoring locations of the test, which we consider to be the measurement scale. These results are compared to previously analyzed single-hole tests conducted at multiple measurement scales. We hypothesize that the permeability scale effect is controlled by the connectivity of fluid conducting fractures, which also increases with scale. This observation and hypothesis is consistent with existing scaling theories in fracture connectivity, although subsurface fracture connectivity cannot be measured directly with present technology. These results suggest the need to obtain permeability estimates that are commensurate with the scale of intended use.
Transfer of micro/nano-scale pillars and wires on conducting thermoplastic composite coated arbitrary substrates

In this paper, we demonstrate an approach to simultaneously transfer single crystal devices in the shape of vertically oriented 1-D silicon micropillars, while establishing a direct electrical and mechanical connection to a target surface of any topology using an innovative harvest/lift-off process coupled with a conducting thermoplastic composing of polyaniline (PAni) and polymethylmethacrylate (PMMA) composite. The mixture acts as a stable anchoring layer and as a conducting layer for the bottom electrode. The insulating layer comprised of PMMA while the top electrode can be formed by evaporating thin metal films.
Percolation in Heavily Doped Semiconductors

Determination of the detailed nature of the semiconductor-to-metal transition in doped semiconductors is obscured by the random placement of the impurities. We report the results of a Monte Carlo percolation calculation which show that the details of the Hall-coefficient data in Si:P and, less clearly, in Ge:Sb are consistent with the existence of a discontinuous transition from insulator to metal at $T={0}^{\ensuremath{\circ}}\mathrm{K}$ as the impurity concentration is increased.
A diffusion analysis of transient subsurface γ′-Ni3Al formation during β-NiAl oxidation

Abstract Cross-sectional transmission electron microscopy has demonstrated γ ′-Ni 3 Al formation at the alloy/oxide interface during β-NiAl (1 1 0) oxidation under specific conditions. Diffusion analysis was applied to interpret this subsurface phase formation process. It showed that thermodynamically sufficient conditions for phase formation could be achieved with increasing temperature during the early oxidation stage. To stabilize continued γ ′ growth, a kinetic requirement needed to be considered, which led to a thickness criterion. The predicted extent of subsurface γ ′ phase formation showed good agreement with the experimental observations.
Stabilization of ballooning modes by energetic particles in tokamaks

A ballooning eigenmode equation, taking into account the presence of energetic particles i n a tokamak, is derived from the Vlasov equation. The numerical solution of this equation demonstrates that the finite-Larmor-radius effect of the energetic particles can have a strong stabilizing effect on ballooning modes. This result supports the observed lack of high-mode-number ballooning instabilities in ISX-B injection experiments.
Sustainable green product design and manufacturing / assembly systems engineering principles and rules with examples

Sustainable product and process engineering, green, lean design, manufacturing / assembly system and factory design / management rules and principles are offered with a focus on ‘monozukuri’. The Japanese phrase, ‘monozukuri’ means sustainable, environmentally friendly, green factories and products with simultaneously integrated product and process designs. Based on the author's extensive research and study of products, processes and factories in the USA, Japan, Europe and China, eighteen ‘monozukuri-focused’ green product, process, factory design & management principles are explained. The rule-based approach introduced in this article, when integrated into an intelligent Sustainable Enterprise Engineering (iSEE:Green) design, will reduce waste at all levels, and create new eco-friendly (a.k.a. Earth-friendly), sustainable opportunities for satisfying rapidly changing market needs.
Coal fly ash as an acid-reducing soil amendment and its side-effects

Coal combustion by-products may offer significant benefits if used properly to neutralize soil acidity, but unintended release of trace components must be considered. A study was conducted with two objectives: (i) To compare the efficacy of two different preparations of fly ash with that of conventional ag lime for their ability to raise soil pH and reduce exchangeable Al; and (ii) to determine if the Al applied in fly ash produces detrimental changes in soil properties following subsequent acidification. Either fly ash in one of two forms, or conventional ag lime, was applied to three acid soils (Anselmo loam, Valentine sandy loam, and Holdrege sandy loam) in a pot study at rates equal to 0.5, 1.0, and 1.5 times the soils' lime requirements. Soils were equilibrated in triplicate at approximately 33 kPa water potential in the greenhouse for 315 days (liming phase), during which pH and exchangeable aluminum (Al) were measured. The soils were then acidified under similar conditions for 439 days (acidification phase) by adding dilute acid solution to simulate management-induced acidification, and pH and exchangeable Al were then measured again. Both fly ashes and ag lime were effective in raising soil pH by up to 1.2 units and in reducing exchangeable Al by up to 5.6 mg kg -1 . Two-way interactions involving soil, liming material, and rate of application produced different results for combinations of these factors. All amendments helped the soils resist subsequent acidification compared with zero-rate treatments but differed based on the 3-way combinations of soil, liming material, and rate of application. We concluded that overliming (as indicated by exceeding the target pH of 6.5) is a problem with all liming materials on the coarsest soils, suggesting that lime calibration should be re-examined. The fly ash materials seem to contribute to soil exchangeable Al after acidification, but this contribution is inconsequential if soil pH values are maintained at agronomic optima.
A Phase I/II Study of the Janus Kinase (JAK)1 and 2 Inhibitor Ruxolitinib in Patients With Relapsed or Refractory Acute Myeloid Leukemia

Background Ruxolitinib is a potent and specific JAK1/JAK2 inhibitor recently approved for the treatment of myelofibrosis.
Depletion of cellular polyamines by α-difluoromethylornithine increases 1,3-bis(20chloroethyl)-1-nitrosourea-induced sister-chromatid exchanges

Abstract Treatment of cells with α-difluoromethylornithine (DFMO), which leads to the intracellular depletion of the polyamnes putrescine and spermidine, is known to increase the cell kiling induced by the DNA cross-linking chemotherapeutic agent 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU0. This has been attributed to a change in DNA conformation that is related to the intracellular polyamine content and a concomitant change in accessibility of BCNU to reactive sites in DNA. Cytogenetic experiments were previously carried out showin that DFMO pretreatment also increased sister chromatid exchanges (SCEs) induced by BCNU. Subsequently, there was difficulty in repeating this phenomenon, which led to retraction of the results. More recent information indicates, however, that a change in protocol occurred between the time of the original experiments and the repeat experiments. Because cell killing by genotoxic agents, such as X-rays, can be related to cytogenetic damage, and agents that cause deformation of DNA do leads to SCEs, experiments have now been carried out to see whether or not the subtle deformation caused by polyamine depletion could, indeed, lead to the induction of increased SCEs by BCNU, as had been originally postulated. When the experiments were carried out with the original protocols, pretreatment with DFMO did increase BCNU-induced SCEs. Modification of the protocols, especially washing of the cells before the addition of BCNU, which reduces the toxicity, reduced the DFMO effect and in some experiments even obliterated it.
Relative permeability and non-wetting phase plume migration in vertical counter-current flow settings

In this work, we investigate the impact of co-current to counter-current flow reversals on the migration dynamics of a non-wetting phase plume in a porous medium. The presented results and observations have direct application to CO2 injection into saline aquifers where a less dense CO2-rich plume migrates during and following the injection period. Counter-current gravity segregation experiments were performed in a vertical glass-bead pack with brine and iC8 as analog fluids to mimic the behavior of a CO2/brine system of relevance to CO2 sequestration processes. Four-electrode resistivity measurements were used to monitor the migration of the non-wetting phase (iC8) by relating the resistivity index (RI) to the brine saturation. The observations are compared with numerical calculations to demonstrate that standard co-current relative permeability measurements are inadequate to reproduce the experimental observations. A reduction in the relative permeability of both phases, in particular for the non-wetting phase, is required to improve the agreement between experimental observations and numerical calculations. Numerical calculations based on co-current input data predicts a much faster migration of the non-wetting phase to the top of the column than what is observed in the segregation experiments. Our findings demonstrate that counter-current flow affects the phase's mobilities, because of interfacial coupling, and should therefore be considered in the modeling of injection/storage of CO2 in saline aquifers: simulation of CO2/brine dynamics based on co-current relative permeability measurements is likely to render estimates of migration time/distance in significant error.
Noncompliance in screening follow-up among family planning clinic patients with cervical dysplasia☆

This investigation estimated the extent of noncompliance with follow-up to screening for cervical dysplasia at a public health family planning clinic. Available data also permitted examination of the relationship between selected background characteristics and compliance with follow-up. Noncompliance was defined as failure to respond to notification of an abnormal cervical smear (Class III, IV, or V) by failing either to make a follow-up appointment or to keep such an appointment after it was made. The sample consisted of 177 women with abnormal cervical smears who were screened at the Forsyth County Family Planning Clinic between January 1, 1980, and June 30, 1981. Information on the women's compliance with the request for follow-up was obtained from a file specifically kept for this purpose by the clinic nurse. Background characteristics were obtained by reviewing clinic records. Results indicated that approximately 17% of the sample was noncompliant. Noncompliant patients were more likely to be unmarried, less educated, younger, and to have fewer total health problems than women who returned for follow-up. Logistic regression analysis revealed that the number of health problems and educational attainment were the most important predictors of noncompliance.
Public Administration in Dark Times: Some Questions for the Future of the Field

This essay identiﬁes two problems that impede the ability of public administration to govern effectively in dark times. First, public administration has failed to adequately acknowledge itself as an arbiter of political conﬂict and as a discipline responsible for shaping societal affairs. Second, the ﬁeld is entrenched in a bureaucratic pathology that limits its capacity to address complex policy problems. We argue that these issues show a clear need for the reinvigoration of democratic ethos as the foundation for public administration. Building on the ideas of some Minnowbrook III working groups, we pose questions to help begin discussions about both democratic ethos and the ability of public administration to govern in dark times.
APPLYING SYSTEMS ENGINEERING AND ICON‐DRIVEN SIMULATION TECHNIQUES TO THE WASTE DISPOSAL PROBLEM AT HANFORD, WA

This paper provides a case study on the use of systems engineering to create the hierarchical description of a decision-support model for the tank waste remediation program at Hanford, WA. A commercial, off-the-shelf (COTS) icon-driven modeling package is used to sharply reduce the model development effort. A database-driven information management tool, used to describe the model functions, requirements, architectures and tests, provides the traceability and editing power to document the development with little added effort.
Lactic acidosis, diabetes mellitus and the biguanide compounds

After a brief outline of the factors regulating plasma lactate levels in normal and diabetic subjects, the AA. summarize the history, the possible mechanism of action and the therapeutic applications of the guanidine derivatives. The possibility that these drugs may increase the danger of lactic acidosis is discussed.
Studies of the production rate of cosmic-ray produced 14C in rock surfaces

Abstract We have developed a method of extracting 14C in rock samples which is produced by the direct spallation of oxygen in the rock. The low levels of 14C produced in rocks, approximately 106 atoms/g of rock at an altitude of 2000 m, are detectable only by accelerator mass spectrometry (AMS). This radioisotope can be extracted from the rock by melting in an rf furnace in a flow of oxygen, and earlier work has discussed this in some detail. Several improvements have been made to this system, allowing for processing of up to 100 g of rock sample at one time, and reduction of the blank. Our measurements from Tabernacle Hill, Utah, an intermediate-altitude basalt with well-constrained conventional 14C ages, yield an estimated cosmogenic 14C production rate of about 50 14C atoms/g/yr. When corrected to sea level we obtain a value of 20 ± 2 14 C/g/yr for high-latitude samples.
Acceptor centers in phosphorus doped ZnSe crystals

Abstract Phosphorus doped ZnSe crystals, prepared by melt growth techniques under conditions to enhance the incorporation of phosphorus as a uncompensated acceptor, show two broad luminescence bands at 1.91 and 1.15 eV. Excitation bands resolved from the band edge absorption are found for both emissions. Electron paramagnetic resonance has established the atomic structure of two photosensitive P-centers: isolated P substitutional for Se, denoted by P Se , and clusters of 4 ions. P Se centers are seen their trigonally distorted paramagnetic charge state at 1.3°K before exposing the crystal to light. The crystal behaves electrically as partially compensated high resistivity material where the dominant trap is the P Se acceptor, which acts as sensitizing center for the observed n-type photoconductivity. Infrared quencing with a low energy edge at ≈0.6 eV of photoconduction, of 1.91 eV photoluminescence, and of the P S e paramagnetic resonance; and dark conductivity with an activation energy of ≈ 0.7 eV establish this behavior and provide a tentative relationship between the P S e center and the 1.91 eV luminescence. Similar results are obtained in As doped ZnSe.
The generation gap.

When JACR was first published 10 years ago, most of the current radiology residents were in college, unaware of the intricacies of medical practice and the need for a radiology journal addressing issues in clinical practice, practice management, education, and health services research. It probably seems like yesterday to some, but 10 years is half a generation. Not only has the technology and practice of the specialty evolved in that time, the generational constituency of radiology has changed. In addition to the traditionalists (the silent or greatest generation), the baby boomers, and generation X, we now have generation Y, also known as the millennial generation, as part of the workforce [1]. Generation Y includes people born between approximately 1981 and 2005 [1]. Most of our medical students and residents are part of generation Y, children of the baby boomers. Perhaps some understanding of the characteristics that define this newest generation can help us work together with less frustration. Generation Y members had overscheduled, highly structured childhoods and were raised by parents who praised them for everything [2]. David McCullough Jr gave a commencement speech to the 2012 high school class of Wellesley, Massachusetts, an affluent suburb of Boston. The speech went viral because it resonated with people that someone told generation Y, “You’re not special” [3]:
HIGH SPEED SEMICONDUCTOR LASERS

The strategy and methods to design high speed semiconductor lasers are reviewed here. The formalism for the analysis of intensity modulation, frequency modulation and intensity noise in quantum well lasers is first derived. Using this formalism the process of optimizing the laser structure for high speed operation is presented. In addition to the conventional factors such as the differential gain, photon density, photon lifetime and device parasitics, we also review the critical effects of carrier transport and microwave signal transmission on the dynamic characteristics and design of high speed semiconductor lasers.
Enhancement and depression by inosine of the growth inhibitory action of 5-fluorouracil on cultured Jensen tumor cells

Continuous exposure of Jensen tumor cells in vitro to 1 mM inosine following a 1 hr exposure to 5-fluorouracil resulted in a 5-fold potentiation of growth inhibition. This effect was abolished by the simultaneous presence of 1 mM cytidine and was attributable to altered metabolic processing of drug anabolites after the uptake of 5-fluorouracil had ceased. In contrast, antagonism to 5-fluorouracil was seen when the cells were exposed successively to 1 mM inosine for 1.5 hr and to 5-fluorouracil for 1 hr. In this case the inhibitory action of the drug was diminished by nearly one-half. Quantitation of the potentiation and antagonism was based upon growth delays measured from growth curves obtained by serial photomicrography.
Stability analysis of a semi-rigidly connected simple frame

Abstract A kinematically non-linear analysis of a flexibly-jointed two-bar frame, subjected to eccentric concentrated loads (near the joint), is presented. The geometry is in general non-uniform in terms of bar length and stiffness. The flexible joint is modelled by a rotational spring connecting one member to the other. The studies include (a) assessment of the effect of a linear rotational spring on the frame behaviour (from a pin connection to a rigid connection) and (b) the behaviour under load of a two-bar frame with flexible joints, which initially are virtually rigid, but as the load increases, the slope of the joint bending moment to relative rotation curve changes (non-linear rotational spring). Furthermore, the effects of load eccentricity and slenderness ratio on the response characteristics are fully assessed for both studies.
In-situ phosphatizing coatings III: A water-reducible alkyd baking enamel

We report the successful formulation of stable and compatible in-situ phosphatizing coatings (ISPCs) for a waterborne alkyd-amino baking enamel applied on bare cold-rolled steel (CRS), iron phosphated Bonderite 1000 (BD), and iron phosphated plus Parcolene 60 chromated (BD+P60) coupons. The enhanced coating adhesion of water-based ISPCs is confirmed by the cathodic delamination measurements. After 100 hr of salt spray (fog) test, the corrosion resistance performance (measured by the corrosion disbondment across the “X” scribe, d in mm) of the water-based ISPC on CRS panel (d=4.0−7.0 mm) outperformed that of the control alkyd paint on B-1000 (d=26 mm) and also on BD+P60 (d=14 mm) coupons. The superior coating performance of water-based ISPCs is believed to result from the in-situ metal surface phosphatization as detected by the reflectance FTIR technique.
Importance of the Mechanisms of Blood Coagulation in the Breakdown of Adenosine Triphosphate in Blood

THE data presented in this communication demonstrate that the degradation of adenosine triphosphate (ATP) in whole blood, initiated by the damaged wall of a blood vessel, can only take place in conjunction with activation of the coagulation mechanisms.
The shapes of sensory and motor neurones and the distribution of their synapses in ganglia of the leech: a study using intracellular injection of horseradish peroxidase.

Three types of sensory neurones and two kinds of motor neurones in the segmental ganglion of the leech were examined with the light and electron microscope after intracellular injection of horseradish peroxidase (HRP) for a histological marker. The aim was to develop a method for identifying the synapses of specific cells in the ganglion’s complex neuropil and to form a picture of their distribution and structure. Reaction of HRP with different benzidine derivatives produces opaque and electron dense deposits. For light microscopy a blue stain is formed that makes processes visible in whole mounts millimeters away from the injection site at the soma. The reaction product for electron microscopy is distributed throughout the cytoplasm, yet ultrastructural details are preserved. The sensory neurones that respond specifically to touch or pressure or noxious mechanical stimuli to the skin share in their branching pattern a number of common features. A single process arising from each cell body forms large primary branches that pass through the neuropil and leave the ganglion by the ipsilateral connectives and roots. Within the neuropil these branches give rise to numerous smaller secondary processes. In contrast, the annulus erector and large longitudinal motoneurones send their main process across the ganglion to bifurcate and enter the contralateral roots. Secondary processes of the motoneurones are highly branched and more numerous than those of the sensory cells. Each type of sensory and motor cell is distinguished by the shape, length and distribution of its secondary processes. Secondary processes of sensory neurones exhibit numerous swellings and irregularly shaped fingers. Electron micrographs show that the sensory neurones make synapses at these specializations, each of which contacts several postsynaptic processes. The sensory neurones receive inputs at the same fingers and swellings, an arrangement suggesting that regions within a cell’s arborization may function semi-autonomously. The main process and large branches of the two motor neurones are studded with spines a few micrometres long and a fraction of a micrometre in diameter. Vesicle-containing varicosities from other cells make synaptic contact primarily with the spines, which themselves have few vesicles. These two motor neurones are largely, if not entirely, postsynaptic to other neurones within the leech nervous system.
GRKs and β-arrestins: roles in receptor silencing, trafficking and signaling

Stimulation of cell-surface seven-transmembrane receptors (7TMRs) elicits biological responses to a wide range of extracellular signals, including many hormones. Classically, heterotrimeric GTP-binding proteins (G proteins) are recruited to the activated conformation of 7TMRs. Only two other families of protein have this remarkable characteristic: G-protein-coupled receptor kinases and beta-arrestins. These two protein families have long been known to have a central and coordinated role in the "desensitization" of G protein activation by 7TMRs. In addition, G-protein-coupled receptor kinases and beta-arrestins are involved in an increasing number of interactions with non-receptor proteins, broadening the variety of their cellular functions. These newly appreciated attributes of these two families of protein highlight their unique ability to coordinate the various aspects of 7TMR functions.
Barriers to Environmental Sacrifice: The Interaction of Free Rider Fears with Education, Income, and Ideology

Sacrificing individual material interests for collective benefits involves trust that others will act in good faith. Inherent to situations concerning collective goods is the problem of the free rider that plagues collective action: the individual who maximizes their short-term interests at the cost of the greater good. Prior research in environmental sociology has identified various social structural factors predicting pro-environmental behavior and concern, while research on social dilemmas has explored the role of trust in determining cooperation in situations regarding collective goods. This research draws upon these areas of scholarship to examine the interaction between free rider fears with education, income, and ideology in determining the willingness of Americans to sacrifice individual interest for environmental protection through an analysis of 2010 General Social Survey data. Findings help differentiate the engagement of pro-environmental behavior from general environmental concern, with the f...
Shark Tooth Weapons from the 19th Century Reflect Shifting Baselines in Central Pacific Predator Assemblies

The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific), like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah) and the Dusky (C. obscurus), were present in the islands during the last half of the 19th century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity.