cssi/SciSciGPT-SciSciNet huggingface dataset:
5-Bromomethyl fluorescein (5-BMF) for derivatization of carboxyl containing analytes for use with laser-induced fluorescence detection.

Purpose. 5-Bromomethyl fluorescein (5-BMF) was evaluated in this work as a pre-column, off-line derivatizing reagent for analytes containing a free carboxyl group. The reagent possessed high molar absorptivity and quantum yield and it's excitation maximum matched the intense 488.0 nm emission line of an argon ion laser. The thermal and photo-stability of the reagent were also suitable for our work. Methods. A mixture of 5-BMF,. palmitic acid, 18-crown-6 and potassium carbonate was reacted at 76°C for one hour. The reaction yield was maximized by a sequential single-factor optimization of the reaction variables. Spectral characterizations were accomplished using conventional instrumentation and detection limits were evaluated using a laboratory constructed laser-induced fluorescence (LIF) detector which was optimized for concentration detection. Results. Two apparent conjugates of palmitic acid were formed under the reaction conditions employed. The conjugate chosen for quantitative purposes was stable at room temperature over 24 hours and possessed high molar absorptivity (128,832 M−1cm−1) and quantum yield (0.82) under basic conditions. The excitation and emission maxima of the conjugate were 500 nm and 523 nm respectively which maintains suitability for argon-ion laser excitation. An argon-ion LIF detector suitable for use with conventional liquid chromatography was constructed. A detection limit of 7.56 × 10−10M of palmitic acid was achieved at a signal to noise ratio of three, using the strong 488.0 nm laser emission line and a commercially available flow cell component. This corresponds to 38 femtomoles of palmitic acid on-column. Conclusions. The concentration detection limit was superior to literature reports for detection of fatty acids. The mass detection limit provided approximately an order of magnitude improvement over conventional fluorescence. The reagent is potentially useful for analysis of carboxyl containing analytes at low concentrations.
Pre-Detonation Lifetime and Mass of Supernovae from Galaxy Density Wave Theory

Stars in a normal spiral galaxy are formed in a shock front on the inner edge of a spiral arm, according to non-linear density wave theory, then drift across the arm as they age. Ten of the nineteen supernovae measured occur at the innermost edge of a spiral arm, implying a lifetime of less than five million years. Assuming a supernova is a single star at the end of its evolutionary life, the mass implied by this lifetime is greater than 35 solar masses. (Full paper in press, Publ. Astron. Soc. Pacific).
The Observability of Metal Lines Associated with the Lyα Forest

We develop a prescription for characterizing the strengths of metal lines associated with Lyα forest absorbers (LYFAs) of a given neutral hydrogen column density NH I and metallicity [O/H]. This line observability index (LOX) is line specific and translates, for weak lines, into a measure of the equivalent width. It can be evaluated quickly for thousands of transitions within the framework of a given model of the Lyα forest, providing a ranking of the absorption lines in terms of their strengths and enabling model builders to select the lines that deserve more detailed consideration, i.e., those that should be detectable in observed spectra of a given resolution and signal-to-noise ratio. We compute the LOX for a large number of elements and transitions in two cosmological models of the Lyα forest at z ~ 3 derived from hydrodynamic simulations of structure formation. We present results for a cold dark matter universe with a cosmological constant; an Ω = 1 cold dark matter model yields nearly identical results, and we argue more generally that the LOX predictions are insensitive to the specific choice of cosmology. We also discuss how the LOX depends on redshift and on model parameters such as the mean baryonic density and radiation field. We find that the O VI (λλ1032, 1038) doublet is the best probe of the metallicity in low column density LYFAs (NH I ≈ 1014.5 cm-2). Metallicities down to [O/H] ~ -3 yield O VI absorption features that should be detectable in current high-quality spectra, provided that the expected position of the O VI feature is not contaminated by H I absorption. The strongest transitions in lower ionization states of oxygen are O V (λ630), O IV (λ788), and O III (λ833). These absorption lines are all predicted to be stronger than the O VI feature, but even at redshifts 3-4 they will have to be observed in the ultraviolet, and they are extremely difficult to detect with present UV instruments, such as the Space Telescope Imaging Spectrograph (STIS). At lower redshifts, detection of these lines may be possible in STIS spectra of the very brightest QSOs, while one may have to wait for next-generation instruments such as the Cosmic Origins Spectrograph (COS) to detect such lines in a number of high-redshift QSOs. The strongest metal lines with rest frame wavelength larger than 912 A associated with higher column density LYFAs at z ~ 3 are C III (λ977) and Si III (λ1206.5), which peak at NH I ~ 1017 cm-2. Of the lines with rest wavelengths λr > 1216 A, which can potentially be observed redward of the Lyα forest, the C IV (λλ1548, 1551) doublet is expected to dominate in all LYFAs, regardless of the value of NH I. We argue that C IV and C II absorption may peak in different spatial regions, and that comparison of single-phase models of the C IV/C II ionization ratios with observed C IV/C II column density ratios can lead to an overestimate of the ionization parameter in the central parts of the absorbers.
Austria: The 1999 Parliament Elections and the European Union Members’ Sanctions

The 1999 parliamentary elections in Austria sparked a fire of controversy in the European Union. Led by the far-right activist Joerg Haider, the Freedom Party achieved a second place victory, causing leaders and activists to voice their concerns about Austria's future. Acting on that apprehension, the individual members of the European Union joined together to issue diplomatic sanctions against Austria, an unprecedented action. When the sanctions were lifted in September, 2000, the European Union was left to reexamine its role and to determine whether to amend its founding treaties to reflect any changes in the relationship between the government of the European Union and its Member States.
Organic matter in meteorites: molecular and isotopic analyses of the Murchison meteorite.

Carbonaceous chondrites comprise a unique subset of meteorites. Two classes of carbonaceous chondrites, the so-called CI1 and CM2 chondrites, are particularly interesting, in part because of their relatively high carbon content and the fact that most of this carbon is present as organic matter. This material is largely macromolecular but also contains a complex mixture of organic compounds that include carboxylic acids, dicarboxylic acids, amino acids, hydroxy acids, sulfonic acids, phosphonic acids, amines, amides, nitrogen heterocycles including purines and a pyrimidine, alcohols, carbonyl compounds, and aliphatic, aromatic, and polar hydrocarbons. The organic-rich CI1 and CM2 chondrites also contain an extensive clay mineralogy and other minerals that are believed to be indicative of an early episode of hydrous activity in the meteorite parent body. Recent stable isotope measurements have shown the organic matter in general, to be substantially enriched in deuterium and the discrete organic compounds to be enriched in 15N and somewhat enriched in 13C relative to terrestrial matter. These findings suggest that the organic matter is comprised of, or is closely related to, interstellar organic compounds. The organic chemistry of these meteorites is consistent with a formation scheme in which (1) a parent body was formed from volatile-rich icy planetesimals containing interstellar organic matter, (2) warming of the parent body led to an extensive aqueous phase in which the interstellar organics underwent various reactions, and (3) residual volatiles were largely lost leaving behind the suite of nonvolatile compounds that now characterize these meteorites.
A Review of “Transport and Ethics: Ethics and the Evaluation of Transport Policies and Projects”

The author wrote this book because he observed that many people who opposed the use of cost-benefit analysis (CBA) in public decision making could not clearly articulate their objections. van Wee c...
Implementing High-Performance Geometric Multigrid Solver with Naturally Grained Messages

Structured grid linear solvers often require manually packing and unpacking of communication data to achieve high performance.Orchestrating this process efficiently is challenging, labor-intensive, and potentially error-prone.In this paper, we explore an alternative approach that communicates the data with naturally grained messagesizes without manual packing and unpacking. This approach is the distributed analogue of shared-memory programming, taking advantage of the global addressspace in PGAS languages to provide substantial programming ease. However, its performance may suffer from the large number of small messages. We investigate theruntime support required in the UPC++ library for this naturally grained version to close the performance gap between the two approaches and attain comparable performance at scale using the High-Performance Geometric Multgrid (HPGMG-FV) benchmark as a driver.
Dose effects of nicotine gum

Abstract Nicotine gum has been shown to be effective in improving abstinence rates, and in reducing post-cessation withdrawal distress and weight gain. However, the dose effects of nicotine gum on these outcomes is not known. In the present study, we varied the amount of 2 mg nicotine gum prescribed to motivated quitters to explore the hypotheses (a) that motivated quitters would use more pieces of gum when coached and counseled to do so and (b) that there would be a dose-related effect of gum use on abstinence, withdrawal symptoms, and weight gain. One hundred seventy-seven volunteers were assigned to chew either 0, 7, 15, or 30, pieces per day of 2 mg nicotine gum. Biological verification of gum use and smoking abstinence were assessed in community volunteers who attended an intensive behavioral counseling program for smoking cessation while using nicotine gum for 3 months. In the survival analysis at 12 weeks, gum-group assignment was not related to successful abstinence. In the subset of 42 abstinent subjects, there was a strong positive relationship between pieces per day of nicotine gum used and saliva cotinine. However, there was substantial variability in groups of subjects reporting similar amounts of gum use. Withdrawal symptom reporting was not related to either gum use or cotinine levels. Weight gain was significantly related in a dose-dependent manner to salivary cotinine levels, but not to gum group assignment, with high and low cotinine subjects gaining on average, 4.0 and 6.6 pounds, respectively. Discussion of the use of high levels of nicotine gum is addressed. Consistent with earlier work, the study provided further support for the relationship between nicotine replacement level and postcessation weight gain.
The interaction between soot and NO formation in a laminar axisymmetric coflow ethylene/air diffusion flame

The interaction between soot and NO formation in a laminar axisymmetric coflow ethylene/air diffusion flame was investigated by numerical simulation. A detailed gas-phase reaction scheme and a simplified soot model were employed. The results show that the formation of NO has little effect on that of soot. However, the formation of soot in the flame significantly suppresses the formation of NO. The peak NO concentration and NO emission index are reduced by 28 and 46%, respectively, due to the formation of soot. The influence of soot on NO formation is caused by not only the radiation-induced thermal effect, but also the reaction-induced chemical effect. Relatively the thermal effect is more significant, causing 25 and 38% reduction, respectively, in peak NO concentration and NO emission index. The chemical effect is caused by the competition for acetylene (C{sub 2}H{sub 2}) between soot and NO formation. The formation of soot consumes acetylene in the flame and thus lowers the formation rate of radical CH. This reduces the reaction rate of CH + N{sub 2} = HCN + N, which is the rate-limiting step of the prompt NO formation route, the dominant route in the studied flame. (author)
Karhunen-Loeve expansion of Burgers' model of turbulence

Characteristics of the Karhunen–Loeve expansion of a strongly inhomogeneous random process possessing small viscous length scales and a large outer scale have been investigated in relation to the application of the expansion to turbulent flow fields. Monte Carlo simulations of a randomly forced Burgers’ equation with zero velocity boundary conditions generate the random process numerically and the Karhunen–Loeve (KL) eigenfunctions and the eigenvalue spectra are computed for different Reynolds numbers. The eigenfunctions possess thin viscous boundary layers at the walls and are independent of Reynolds number in the core, where the random process is quasihomogeneous. The eigenfunctions and eigenvalues of the outer, large scale motions obey a principle of Reynolds number similarity. Eigenvalue spectra contain much of the energy in the first few modes, but they are as broad as ordinary trigonometric power spectra. The rate at which the expansion converges to within 90% of the total energy decreases with increasing Reynolds numbers and the expansion of the mean plus the fluctuation converges more rapidly than the expansion of the fluctuation alone.
Lymphomatoid granulomatosis in a pediatric patient

We report the radiology and pathology of a pediatric patient with lymphomatoid granulomatosis (LG) and review the literature, with an emphasis on the radiological findings and on the small subset of pediatric patients with this rare condition.
Predicting Success of Walleye Stocking Programs in the United States and Canada

Abstract We developed a model to predict the probability of establishing a reproducing population of walleye (Stizostedion vitreum) in lakes and reservoirs in North America. A list of 542 lakes and reservoirs where walleye stocking occurred was obtained by questionnaire survey. Water quality and morphometric data for these systems were obtained from STORET, the national computer data base of the Environmental Protection Agency, and various reports. Two stepwise discriminate analyses were performed on normalized data; the variables area, maximum depth, and pH were found to be significantly related to walleye success in lakes. In addition, the variable date of dam closure was included in the reservoir data set. Using a jackknife discriminate analysis, 71% of the lakes and 72% of the reservoirs were classified correctly. Use of our model increases the probability of predicting the establishment of a self-sustaining walleye population by about 20%.
Geochemical investigation of salt-water intrusion into a coastal carbonate aquifer: Mallorca, Spain

Geochemical processes occurring within the mixing zone on Mallorca, Spain, were investigated in relation to the diagenesis of carbonate minerals and to the development of porosity and permeability within the Pleistocene limestone aquifer. Rock core and ground-water samples were obtained from the fresh-water zone, the mixing zone and the top of the sea-water zone at two sites near the coast. Ground-water withdrawals in the vicinity of one study site depressed the water table to below sea level, resulting in sea-water encroachment and a thin mixing zone. Laboratory tests conducted on the rock core indicated that porosity and hydraulic conductivity were not enhanced within the transitory location of the present-day mixing zone. Vuggy zones in the core correspond to the approximate location of the water table. Because the ground water was supersaturated with respect to the carbonate minerals, dissolution of the limestone aquifer is no predicted for the present-day mixing zone. Results of mass-balance and source-rock calculations indicated an excess of calcium and strontium in the mixing-zone waters in relation to what was expected from conservative mixing. These elevated concentrations are hypothesized to result from limestone dissolution in the vadose zone.
Personality correlates of HIV vaccine trial participation

Individual differences in motivations and behaviors among HIV-negative participants in HIV vaccine trials remain unclear. 127 active participants in vaccine trials completed an anonymous questionnaire assessing motivations for trial participation, personality (as measured by the NEO-FFI), and perceived risk of HIV infection. Results revealed that Neuroticism was positively related to perceived risk of HIV infection, a desire for HIV testing, and a desire for protection from HIV as motivation for trial participation. Implications for personality research in HIV vaccine trials are discussed.
THE CORRELATION BETWEEN PRICE AND OUTPUT CHANGES WHEN THERE ARE MANY GOODS

Abstract It is shown that competition in the production of many goods implies a positive correlation between the elements of a vector of changes in normalized prices and the corresponding vector of changes in outputs.
A method for measuring oxygen consumption and cardiac output in intensive care units.

A simplified measurement of oxygen consumption was investigated in 15 spontaneously ventilating and 11 apnoeic patients in the intensive care unit following open-heart surgery, using a Godart Pulmonet type 11e. Three consecutive measurements were performed on each patient to define the reproducibility of the method. The coefficient of variation of Vo2 was ±3.16 per cent and ±3.42 per cent in spontaneously breathing and apnoeic patients respectively. Arteriomixed venous oxygen difference (Cao2-CvO2) was also measured and cardiac output (CO) calculated using the Fick principle, in the spontaneously ventilating patients. Coefficient of variation of Cao2-CvO2 and CO values were±4.63 per cent and ±4.70 per cent respecetively.
The IκB Kinase Complex (IKK) Contains Two Kinase Subunits, IKKα and IKKβ, Necessary for IκB Phosphorylation and NF-κB Activation

Recently we purified a 900 kDa cytokine-responsive IkappaB kinase complex (IKK) and molecularly cloned one of its subunits, IKKalpha, a serine kinase. We now describe the molecular cloning and characterization of IKKbeta, a second subunit of the IKK complex. IKKbeta is 50% identical to IKKalpha and like it contains a kinase domain, a leucine zipper, and a helix-loop-helix. Although IKKalpha and IKKbeta can undergo homotypic interaction, they also interact with each other and the functional IKK complex contains both subunits. The catalytic activities of both IKKalpha and IKKbeta make essential contributions to IkappaB phosphorylation and NF-kappaB activation. While the interactions between IKKalpha and IKKbeta may be mediated through their leucine zipper motifs, their helix-loop-helix motifs may be involved in interactions with essential regulatory subunits.
A temperature compensated von bertalanffy growth model for tagged red drum and black drum in Texas bays

Abstract Estimates of von Bertalanffy growth model (VBGM) parameters K and L ∞ were made for red drum ( Sciaenops ocellatus ), and black drum ( Pogonias cromis ), tagged and recaptured in Texas bays from November 1975 through June 1985. An annual temperature model was used to examine the growth model when periods of cold temperature were excluded. The best fit of the VBGM for red drum was based on time at large expressed in day-degrees with the coldest 60 days of the year excluded and yielded VBGM parameters estimates (± SE ) of K = 0.422 (0.023) and L ∞ = 918 (21) mm. Black drum data were best fitted with time at large expressed in days with the coldest 120 days of the year excluded and yielded VBGM parameters of K = 0.219 (0.027) and L ∞ = 798 (42) mm. The exclusion of cold periods added to the body of evidence suggesting that scales and otoliths may be useful for ageing these species in the Gulf of Mexico. The source of the tag return (recreational fishermen, commercial fishermen, Texas Parks and Wildlife personnel) affected the parameter estimates. The pooled data, however, appeared to give the most reliable estimates.
Effects of Training in Apparel Design and Product Development on Spatial Visualization Skills

This study examines the effects of indirect training provided by apparel design and product development courses on spatial visualization skills. Spatial visualization skills are measured by using the Apparel Spatial Visualization Test, a domain-specific measure of spatial visualization, and the Paper Folding Test, a general measure of spatial visualization. In a pretestposttest comparison group design, 128 students completed the two tests at the beginning and end of semester courses. Test scores indicate student improvement on both tests of spatial visualization during the course of a semester. Students in Beginning Clothing Construction improved significantly more on the Apparel Spatial Visualization Test than students in Flat Pattern and Computer Aided Design. Students in Computer Aided Design improved significantly more on the Paper Folding Test than students in Beginning Clothing Construction and Flat Pattern. Results support the viability of indirect training provided in these courses as a means to i...
Modulating DNA adsorption on silica beads using an electrical switch

We demonstrate active tuning of DNA adsorption on silica beads using an electrical switch in a microfluidic device; we use electrolysis of water to alter pH in a packed bed of silica beads and switch the silica bead surface between being adsorptive and desorptive for DNA molecules.
Fast and Exothermic Reaction of CO2 and Li3N into C–N-Containing Solid Materials

The conversion of CO2 to valuable compounds, which is considered as an effective approach to solve the global warming, represents a great challenge due to the high stability and low reactivity of CO2. Herein, thermodynamic calculations predicted the feasibility of exothermic reactions between CO2 and Li3N into two important solid materials—carbon nitride and lithium cyanamide. Furthermore, the feasibility was confirmed by experiments, namely, the fast reaction between CO2 and Li3N produced crystal lithium cyanamide and amorphous carbon nitrides. This provides a novel process to control CO2 emissions.
Maternal deployment of the embryonic SKN-1-->MED-1,2 cell specification pathway in C. elegans.

Abstract We have previously shown that the MED-1,2 divergent GATA factors act apparently zygotically to specify the fates of the MS (mesoderm) and E (endoderm) sister cells, born at the 7-cell stage of C. elegans embryogenesis. In the E cell, MED-1,2 activate transcription of the endoderm-promoting end-1 and end-3 genes. We demonstrate by in situ hybridization that med transcripts accumulate both in the EMS cell and in the maternal germline in a SKN-1-dependent manner. Removal of zygotic med function alone results in a weakly impenetrant loss of endoderm. However, med-1,2(−) embryos made by mothers in which germline med transcripts have been abrogated by transgene cosuppression fail to make endoderm 50% of the time, similar to the phenotype seen by RNAi. We also find that reduction of Med or End activity results in aberrant numbers of intestinal cells in embryos that make endoderm. We further show that regulation of the paralogous end-1 and end-3 genes consists of both shared and distinct inputs, and that END-3 activates end-1 expression. Our data thus reveal three new properties of C. elegans endoderm specification: both maternal and zygotic activities of the med genes act to specify endoderm, defects in endoderm specification also result in defects in gut cell number, and activation of the paralogous end-1 and end-3 genes differs qualitatively in the relative contributions of their upstream regulators.
An Effective Classroom Technique for Comparison of Robust Estimators

Abstract A classroom technique is proposed for enabling students to make their own empirical comparisons of different estimators of location. This technique will allow each student to essentially replicate the type of comparisons Stigler (1977) did with his historical data sets. The comparisons are based on a series of simple experiments for which the “true” value of the parameter is known.
Neural components of altruistic punishment

Altruistic punishment, which occurs when an individual incurs a cost to punish in response to unfairness or a norm violation, may play a role in perpetuating cooperation. The neural correlates underlying costly punishment have only recently begun to be explored. Here we review the current state of research on the neural basis of altruism from the perspectives of costly punishment, emphasizing the importance of characterizing elementary neural processes underlying a decision to punish. In particular, we emphasize three cognitive processes that contribute to the decision to altruistically punish in most scenarios: inequity aversion, cost-benefit calculation, and social reference frame to distinguish self from others. Overall, we argue for the importance of understanding the neural correlates of altruistic punishment with respect to the core computations necessary to achieve a decision to punish.
Glycogen synthase in the rat tapeworm, Hymenolepis diminuta--II. Control of enzyme activity by glucose and glycogen.

Abstract 1. 1. The proportion of activity in the physiologically active I form of glycogen synthase in Hymenolepis diminuta (Cestoda) decreased in the worm when the rat host was fasted and was greatly increased in the cestode 1 hr after a 24 hr fasted rat was refed. 2. 2. The increase in glycogen synthase I activity was due to glucose present in the host gut after feeding, not to other physiological changes in the rat intestine due to meal consumption. 3. 3. Incubation of intact H. diminuta in vitro with glucose also resulted in the conversion of glycogen synthase D to I. 4. 4. Glucose does not appear to affect the glycogen synthase complex directly, because neither the total synthase converted to I nor the rate of conversion was affected by glucose in a partially purified homogenate. 5. 5. High concentrations of glycogen inhibited the synthase D to I conversion and high mol. wt glycogen was a more effective inhibitor than low mol. wt glycogen.
Characterization of the Molecular-Chaperone Function of the Heat-Shock-Cognate-70–Interacting Protein

A histidine-tagged form of the recently discovered molecular chaperone, 70-kDa heat-shock cognate (Hsc70)-interacting protein (Hip), has been expressed in Escherichiu coli and purified to near homogeneity. This protein remains soluble when expressed in E. coli. Several important properties of this chaperone have been investigated. HPLC size-exclusion chromatography indicates that the chaperone forms a tetramer similar to what has been reported for the native protein from rat liver cytosol. The recombinant form of Hip did not catalyze the hydrolysis of ATP and ATP analogs, although fluorescence measurements indicated that the chaperone recognizes anthraniloyl-dATP, anthraniloyl-ADP, and 2’-0trinitrophenyl-ATP. The role of Hip as a molecular chaperone has been confirmed by its ability to strongly bind to the reduced, carboxymethylated form of a-lactalbumin. This interaction is specific for non-native domains since native a-lactalbumin fails to interact with Hip. Fluorescence-anisotropy measurements indicate that reduced, carboxymethylated lactalbumin binds Hip with a K,, of 5 pM. Although Hip appears to be able to bind nucleotides and non-native proteins, it is unable to facilitate the refolding of two denatured proteins, E. coli alkaline phosphatase and mitochondria1 malate dehydrogenase. Hip inhibited the refolding of alkaline phosphatase and malic dehydrogenase. Inhibition occurred at near stoichiometric levels of Hip and could not be reversed by the addition of ATP. These results suggest that Hip may regulate the function of the Hsp70 molecular chaperone complex in vivo and play a critical role in protein folding in the eukaryotic cytoplasm.
Further results on self-similar network traffic modeling with scale-invariant systems

Discrete-time linear systems that possess scale-invariance properties even in the presence of continuous dilation were proposed by Zhao and Rao. The paper presents results of subsequent investigation characterizing self-similarity properties of discrete-time signals synthesized by these systems. It is shown that white noise inputs to these linear scale invariant systems produce self-similar outputs regardless of the marginal distribution of the noise. We investigate this with different types of inputs and in most instances the outputs are fractional Gaussian and self-similar. This is confirmed by generating the fractional Gaussian noise from the fractional Brownian motion and comparing its characteristics with the system output. For heavy tailed input distributions, the output is also heavy-tailed and self-similar. It is also shown that it is possible to synthesize statistically self-similar signals whose self-similarity parameters are consistent with those observed in network traffic.
4-Formylaminooxyvinylglycine, an Herbicidal Germination-Arrest Factor from Pseudomonas Rhizosphere Bacteria

A new oxyvinylglycine has been identified as a naturally occurring herbicide that irreversibly arrests germination of the seeds of grassy weeds, such as annual bluegrass (Poa annua), without significantly affecting the growth of established grass seedlings and mature plants or germination of the seeds of broadleaf plant species (dicots). Previously, Pseudomonas fluorescens WH6 and over 20 other rhizosphere bacteria were isolated and selected for their ability to arrest germination of P. annua seeds. The germination-arrest factor (GAF, 1) responsible for this developmentally specific herbicidal action has now been isolated from the culture filtrate of P. fluorescens WH6. Purification of this highly polar, low molecular weight natural product allowed its structure to be assigned as 4-formylaminooxy-l-vinylglycine on the basis of NMR spectroscopic and mass spectrometric data, in combination with D/L-amino acid oxidase reactions to establish the absolute configuration. Assay results for P. annua inhibition by related compounds known to regulate plant growth are presented, and a cellular target for 1 is proposed. Furthermore, using bioassays, TLC, and capillary NMR spectroscopy, it has been shown that GAF (1) is secreted by all other herbicidally active rhizosphere bacteria in our collection.
The use of medical services under prepaid and fee-for-service group practice

Abstract This study compares medical care use under two prepaid plans offered to the same group of employees and their families. One is a Kaiser plan under which all care is provided on a prepaid basis by a closed panel group practice, and hospital care is provided in hospitals owned by the Kaiser system. Thus physicians are at risk for the entire costs of the covered services of their enrollees. Under the other plan. Clinic plan for short, physician services and outpatient ancillary services are provided by a large, predominantly fee-for-service group practice while hospital care is covered by a Blue Cross policy incorporated into the plan. Thus physicians under this plan are not at risk for the hospital costs of their enrollees and, since prepaid patients are such a small percentage of their total patient populations and they usually do not know if a patient is prepaid or fee-for-service, they are unlikely to treat their prepaid patients differently from their fee-for-service patients. Our findings show that with minor exceptions, the pattern of medical care use under the two forms of group practice is strikingly similar. (1) The rate of ambulatory care is much the same, averaging 2.97 physician visits per year for Kaiser members and 3.05 for Clinic members. (2) There is no significant difference in the rates of patient-initiated visits and physician-initiated visits, either in terms of visits per plan member or per episode of illness. (3) Most important, hospital use under the two plans is practically identical. The age-sex adjusted number of hospital days per 1000 personyears is 249.8 for Kaiser members and 250.7 for Clinic members. These rates are low not only compared to the national rates and rates under alternative insurance plans but also compared to some other prepaid group practice plans. The few differences which do exist are minor. Clinic members are somewhat heavier users of preventive services and of some outpatient ancillary services, notably laboratory tests used in preventive care and to a lesser degree. X-rays. But the overall picture which emerges is one of great similarity between the patterns of use under the two plans. We hypothesized that the conservative use of hospital as well as of ancillary and of physician-initiated services under fee-for-service group practice is due largely to the control over the supply of physicians exercised by the group, which is unlikely to add physicians unless all its members are fully occupied.
OBSERVATIONS ON THE BURROWING RODENT SPALAX IN IRAQ

ment of the rodent condyle in the glenoid fossa being greatly accentuated. The lower jaw can be pulled further posteriorly than in other rodents; a special flange of the squamous portion of the temporal has been evolved to check this backward movement and the external auditory meatus has become displaced somewhat posteriorly, also. Vinogradov (1927) has discussed this masticatory situation in Spalax in somewhat greater detail, but I find his description of the presence of a secondary, or false, mandibular fossa, indented in part into the typmanic bulla, to be misleading. I also find his drawing to be misleading in the implication that something new is formed. Actually, the whole arrangement seems merely to be a further specialization of the already specialized rodent jaw mechanism; whether the bursa in Spalax does or does not involve any surface of the tympanic bulla can only be determined by dissection. The whole masticatory apparatus is obviously highly effective and very strong. Niethammer and Kammerlowe (1934) released a captive Spalax in a room, only to have it immediately begin tearing the plaster off the wall. They spoke, too, of the rapid disappearance of their specimen into dry stony ground. In contrast with the obvious specialization of the jaws, the feet are small and relatively delicate (Plate I); the claws are merely blunt round nubbins. I had some opportunity to observe these interesting animals while a member of the 1954-55 Iraq-Jarmo Archeological Expedition of the Oriental Institute, University of Chicago.' No detailed study could be attempted, however, because of the press of more immediate duties connected with the excavations. But in this part of the world Spalax obtrudes itself upon the archeologist's consciousness, for the rodent is usually a prior excavator in the archeologist's site and has often been mixing things up for thousands of years, to the exasperation of man, who thus finds small cultural artifacts displaced vertically (not always downward) and out of stratigraphic sequence. In addition, this same type of displacement of materials is always a potential source of error in collecting charcoal to be used for radiocarbon (C14) dating. The surface mounds of Spalax could easily be mistaken for those of American pocket gophers, and have sometimes been mistaken for the mounds of true
Important Geological Properties of Unconventional Resource Shales

The revelation of vast global quantities of potentially productive gas and oil-prone shales has led to advancements in understanding important geological properties which impact reservoir performance. Based upon research on a variety of shales, several geological properties have been recognized as being common and important to hydrocarbon production. (1) transport/depositional processes include hemipelagic ‘rain’, hyperpycnal flows, turbidity current flows, tempestites, wave-reworking, and contour currents in both shallow and deep water settings. (2) Common shale minerals include clays, quartz, calcite, dolomite, apatite, and pyrite; organic constituents include spores (Tasmanites), plant remains, biogenic quartz and calcite, and arenaceous foraminifera. (3) Porosity and permeability are characteristically low with pore sizes ranging down to the nanoscale. Main pore types include intergranular (including pores within clay floccules), porous organic matter, porous fecal pellets, and microfractures. (4) Important geochemical characteristics include organic richness (>3%), maturity (>1.1%Ro for shale gas and 0.6–0.9% for shale oil) and type (I–IV), in addition to certain biomarkers which are indicators of bottom water oxicity during deposition. Remaining hydrocarbon potential [RHP = (S1 + S2)/TOC] also reflects temporal environmental changes. ‘Isotopic reversals’ can be used to detect best producing areas in shale-gas plays. (5) Lithofacies stacking patterns and sequence stratigraphy are the result of eustatic depositional history. A general sequence stratigraphic model is presented here that highlights this commonality. (6) Geomechanical properties are key to drilling, fracturing and production of hydrocarbons. Brittle-ductile couplets at several scales occur in shale sequences. (7) Geophysical properties, when calibrated to rock properties, provide a means of regionally to locally mapping the aforementioned properties. (8) Economic and societal considerations in the exploration and development of resource shales are garnering attention. Many potentially economic shale-gas and shale-oil plays are being identified globally. Risks and uncertainties associated with gas- and oil-rich shales include the lack of long-term production histories, environmental concerns related to hydraulic fracturing, uncertainty in calculating hydrocarbons-in-place, and fluctuations in supply, demand, and price.
On the minimax optimality of wavelet estimators with censored data

Abstract Wavelet-based density estimators with randomly right-censored data are considered. We investigate the asymptotic rates of convergence of estimators based on thresholding of empirical wavelet coefficients. Unlike the complete data case, the empirical wavelet coefficients are constructed through the Kaplan–Meier estimators of the distribution functions. It turns out that these coefficients can be approximated by an average of i.i.d. random variables with a certain error rate. We show that the estimators achieve nearly optimal minimax convergence rates within logarithmic terms over a large range of Besov function classes B pq α , α > 1 / p , p ⩾ 1 , q ⩾ 1 , a feature not available for linear estimators when p 2 .
Application of Conformation-Dependent Antibodies: Enhancement of Enzyme Activity of L-Glutamate Dehydrogenase [L-Glutamate NAD(P) Oxidoreductase (Deaminating) EC 1.4.1.3]

Abstract By using a nonprecipitating system, it was found that the enzyme activity of L-glutamate dehydrogenase [L-glutamate NAD(P) oxidoreductase (deaminating) EC 1.4.1.3] (I) is enhanced by the addition of small amounts of anti-I-serum. It is suggested that this enhancement is due to the ability of conformation-dependent antibodies to maintain L-glutamate dehydrogenase in a more favorable conformation and thereby influence the rate of conversion of sodium a-ketoglutarate to sodium glutamate.
PRIMARY SOLAR REACTION DEPENDENCE ON DEUTERON STRUCTURE.

The energy dependence of the process p+p→+e+v has been investigated as a function of the % D state. The pp wavefunction was generated from a Schrodinger equation utilizing a velocity-dependent potential, containing the effect of vacuum polarization, which was fitted to the most recent pp phases. The present likely uncertainty in % D state implies 1 1/2% uncertainty in the reaction rate. The present calculation of Λ2 (0) is 4% less than a previous result. New values of S(0), incorporating recent ft values, have been obtained.
Oxidation of Iron Pretreated for Porcelain Enameling

The thickness of oxide layers formed on enameling iron at short times was measured as a function of temperature to compare the effects of three pretreatments: (1) sulfuric acid pickle, (2) nickel flash, and (3) phosphate coating. The oxides present were examined by X-ray diffraction and metallographic techniques. Nickel-flashed specimens exhibited lowered oxidation rates. The phosphate coating produced significantly rougher metal-oxide interfaces under the process conditions used.
Punctuated equilibrium, morphological stasis and the palaeontological documentation of speciation: a reply to Fryer, Greenwood and Peake's critique of the Turkana Basin mollusc sequence

Fryer, Greenwood & Peake (1983) have recently criticized my analysis of morphological variation in a sequence of Plio-Pleistocene freshwater molluse faunas from the Turkana Basin in E Africa, and question my conclusions that these faunas document speciation and the punctuated equilibrium model of evolutionary change. Unfortunately, these authors misinterpret the nature of the phenotypic variation in African freshwater molluscs and its relevance to my study, and apparently misunderstand punctuated equilibrium theory. Although the majority of their criticisms are therefore erroneous, certain of the points they raise are important: they are addressed here.
What Is Learned in an After-School Computer Club?.

An after-school computer club was developed in which language-minority children learned to master a series of educational computer games through reading instructions, interacting with peers, and interacting with adult mentors. Did twenty-five elementary school children who regularly participated in an after-school computer club during an academic year (treatment group) learn generalizable problem-solving skills as compared to twenty-five non-participating peers who were matched for grade level, gender, and English language proficiency (comparison group)? Based on a dynamic assessment given at the end of the academic year, treatment students were more successful than comparison students in learning how to play a new educational computer game that was presented as a paper-and-pencil mathematics puzzle learning task. This study shows how an informal educational environment can foster generalizable problem-solving skills that transfer to learning in a school environment.
Palaeomagnetism of the Roraima Dolerites

Consistent palaeomagnetic data have been obtained from 19 out of 31 sampling sites in the thick Proterozoic dolerite sills which intrude the Roraima sandstones of the Guiana Shield in Venezuela and British Guiana (now Guyana). Fourteen of these sites, most of which are in noritic dolerite, have remanence orientations which fall into two significantly different groups, approximately opposite in declination, but both with positive inclination: group I, N= 7, D= 334, I=+27, K = 29, α95 = 11, N pole co-ordinate = 63 N 129 W; group II, N= 7, D= 145, I=+39, K = 25, α95 = 12, N pole co-ordinates = 45 S, 13 W. The remaining stable sites, mostly from norite which occurs near the base of some thick sills, have scattered orientations. The unstable sites are characteristically in rocks representing later, iron-enriched stages in the dolerite differentiation sequence. The published potassium-argon ages on these dolerites, and minerals separated from them, give evidence of differential argon loss, but all with a minimum age of about 1500 m.y. There is no clear evidence in the radiometric data of the two separate periods of dolerite intrusion implied by the palaeomagnetism. An additional four sites, group III, are from dykes which are known or inferred to belong to a distinctly younger dolerite suite, of uncertain age. The mean orientation of these four sites is: D= 17, I=+21, K = 36, α95 = 16, N pole co-ordinates = 73 N, 11 E. Ilmenite is the exclusive or predominant oxide accessory seen optically in the magnetically stable Roraima dolerites, whereas magnetite is conspicuous in the unstable sites. Magnetite, however, in very small amount, is the only ferrimagnetic phase indicated by bulk magnetic property measurements (Js/T, J/H) of stable samples. It is presumed to be the carrier of the remanence, and its stability as compared with that (much more abundant) in the unstable sites is tentatively attributed to finer grain size. In the stable, younger, group III dolerites, however, magnetite is the predominant accessory oxide.
Thrombolytic effects of recombinant fibrolase or APSAC in a canine model of carotid artery thrombosis.

BACKGROUNDThrombolytic agents used clinically rely on the activation of plasminogen to plasmin. Plasmin possesses multiple actions including increasing thrombin activity and activation of platelets. Thus, after successful thrombolytic therapy, arterial hyperactivity and reocclusion may be the result of a predominant plasmin-induced thrombogenic action at the site of the residual thrombus. Fibrolase, a direct-acting fibrinolytic enzyme from southern copperhead snake venom, induces rapid clot lysis in vitro. Fibrolase does not rely on plasminogen activation or any other bloodborne components for activity and is not inhibited by any of the rapidly acting serine proteinase inhibitors in blood.METHODS AND RESULTSWe investigated the efficacy of fibrolase to lyse an occlusive thrombus formed in the carotid artery of the anesthetized dog. Electrolytic injury was initiated in both the right and left carotid arteries. Thirty minutes after both arteries were occluded, each vessel was infused with either fibrolase (4...
Graphene‐Wrapped MnO2–Graphene Nanoribbons as Anode Materials for High‐Performance Lithium Ion Batteries

A facile and cost-effective approach for the fabrication of a hierarchical nanocomposite material of graphene-wrapped MnO2 -graphene nanoribbons (GMG) is developed. The resulting composite has a high specific capacity and an excellent cycling stability owing to the synergistic combination of the electrically conductive graphene, graphene nanoribbons, and MnO2 .
The pixon and Bayesian image reconstruction

The primary purpose of this paper is to present the theory of the pixon, its role in Bayesian image reconstruction, and a new method for selecting a pixon basis using fractal dimension concepts: the Fractal Pixon Basis (FPB). In addition, we review our recent work involving the Maximum Residual Likelihood (MRL) criterion for the goodness of fit (GOF) and the Uniform Pixon Basis (UPB). The MRL GOF statistic is based on the autocorrelation of the residuals and eliminates spatially correlated residuals which commonly occur in image reconstruction methods. The presence of spatially correlated residuals causes photometric inaccuracy. Consequently, photometry is greatly enhanced by using the MRL statistic. We also show that through the use of the UPB image representation, a 'Super-Maximum Entropy' solution can be obtained in which entropy is maximized exactly. We present reconstructions obtained with the above methods and compare them to those obtained with the best Maximum Entropy algorithms and demonstrate that use of UPB/MRL concepts provides consistently superior solutions. Finally, we present reconstructions which demonstrate that the FPB obtains the best results so far, significantly superior to both UPB/MRL and ME-based reconstructions.