cssi/SciSciGPT-SciSciNet huggingface dataset:
A hybrid model for intensively managed Douglas-fir plantations in the Pacific Northwest, USA

Recent advances in traditional forest growth models have been achieved by linking growth predictions to key ecophysiological processes in a hybrid approach that combines the strengths of both empirical and process-based models. A hybrid model was constructed for intensively managed Douglas-fir plantations in the Pacific Northwest, USA, by embedding components representing fundamental physiological processes and detailed tree allometrics into an empirical growth model for projecting individual tree and stand development. The simulated processes operated at a variety of scales ranging from individual branches to trees and stands. The canopy structure submodel improved predictions of leaf area index at the stand level when compared to allometric and other empirical approaches (reducing mean square error by 30-42%). In addition, the hybrid model achieved accuracy in short-term volume growth prediction comparable to an empirical model. Biases in 4-year stand growth predictions from the hybrid model were similar to those from the empirical model under thinning, fertilization, and the combination of these treatments; however, volume growth predictions in unmanaged plantations averaged approximately 36% less bias. These improvements were attributed to detailed information on crown structure (i.e. size, location, and foliage mass of primary branches), simple representation of key physiological processes, and improved site characterization. Soil moisture, temperature, and nitrogen mineralization predicted by the hybrid model also agreed closely with observed values from several previous studies. Overall, the model framework will be helpful for future analyses as it can lend insight into the influence of weather and site edaphic factors on growth, help identify mechanisms of response to silvicultural treatments, and facilitate the design of sound management regimes for Douglas-fir plantations across the Pacific Northwest region.
Multivariate analysis and repeated measurements: A primer☆

Abstract Most research designs in critical care medicine inherently are multivariate in that experimental manipulations are expected to produce changes on several dependent variables, including measurements repeated over time. Increased availability of easy to use computer programs has made it practical for investigators to benefit from the advantages of multivariate analyses, such as increased control of experiment-wise type I error rates and enhanced interpretation of treatment effects. Researchers need not understand the mathematical underpinnings of these analytic techniques to make good use of them, and it is the practical application of these statistical methods that is addressed in the present paper. The assumptions necessary for appropriate use of multivariate approaches, as well as discussion of the interpretations to be drawn from the information provided by computer programs, are presented. The multivariate analysis of variance (MANOVA) is discussed as an extension of its univariate counterpart, the analysis of variance (ANOVA), with the added advantage of assessing differential treatment effects simultaneously across multiple dependent measurements. Discriminant analysis, including examples of how to interpret discriminant weights and canonical loadings, is presented as a particularly useful method of providing an in-depth and unique representation of the results of a significant MANOVA. Finally, the utility of MANOVA is extended to repeated measurements experimental designs, including how to analyze and interpret designs that involve both between-subjects and within-subjects factors.
Preliminary experience and development of an algorithm for the optimal use of the laparoscopic component separation technique for myofascial advancement during ventral incisional hernia repair.

Abstract Background: Component separation technique (CST) enables rectus abdominus medialization, but may cause wound complications. Few published outcomes exist involving laparoscopic CST. Our aim was to examine feasibility and outcomes involving open and laparoscopic (lap) CST during ventral incisional hernia repair (VIHR) and present an algorithm for ventral herniorrhaphy. Study Design: Our design was a retrospective cohort study. Over 22 months, 28 patients underwent one of the following: (i) unilateral (U-) lap CST with open VIHR [n=5], (ii) bilateral (B-) lap CST with open VIHR [n=7], (iii) B-lap CST with lap VIHR [n=8], or (iv) B-open CST with open VIHR [n=8]. Indications for open VIHR included mesh removal, concomitant visceral procedure, wound revision, thin/ulcerated skin, abdominal wall tumor, frozen abdomen, and/or off-midline hernia. During open VIHR, CST was performed in the Ramirez fashion. Lap CST was performed before intraperitoneal access in lap VIHR and after retrorectus dissection in o...
Freeze-drying process design by manometric temperature measurement: design of a smart freeze-dryer.

To develop a procedure based on manometric temperature measurement (MTM) and an “expert system” for good practices in freeze drying that will allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment. Freeze drying was performed with a FTS Dura-Stop/Dura-Top freeze dryer with the manometric temperature measurement software installed. Five percent solutions of glycine, sucrose, or mannitol with 2 ml to 4 ml fill in 5 ml vials were used, with all vials loaded on one shelf. Details of freezing, optimization of chamber pressure, target product temperature, and some aspects of secondary drying are determined by the expert system algorithms. MTM measurements were used to select the optimum shelf temperature, to determine drying end points, and to evaluate residual moisture content in real-time. MTM measurements were made at 1 hour or half-hour intervals during primary drying and secondary drying, with a data collection frequency of 4 points per second. The improved MTM equations were fit to pressure-time data generated by the MTM procedure using Microcal Origin software to obtain product temperature and dry layer resistance. Using heat and mass transfer theory, the MTM results were used to evaluate mass and heat transfer rates and to estimate the shelf temperature required to maintain the target product temperature. MTM product dry layer resistance is accurate until about two-thirds of total primary drying time is over, and the MTM product temperature is normally accurate almost to the end of primary drying provided that effective thermal shielding is used in the freeze-drying process. The primary drying times can be accurately estimated from mass transfer rates calculated very early in the run, and we find the target product temperature can be achieved and maintained with only a few adjustments of shelf temperature. The freeze-dryer overload conditions can be estimated by calculation of heat/mass flow at the target product temperature. It was found that the MTM results serve as an excellent indicator of the end point of primary drying. Further, we find that the rate of water desorption during secondary drying may be accurately measured by a variation of the basic MTM procedure. Thus, both the end point of secondary drying and real-time residual moisture may be obtained during secondary drying. Manometric temperature measurement and the expert system for good practices in freeze drying does allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment.
Lehman's Laws and the Productivity of Increments: Implications for Productivity

Which are the consequences of Lehman's Laws of Software Evolution for the productivity of incrementally developed projects? The concept of Incremental Development Productivity Decline (IDPD), which deals with how the productivity of incrementally developed software develops over its increments, is introduced. It is explained how Lehman's Laws of Software Evolution apply to it and how maintenance and reuse are relevant to both. Every Law of Software Evolution is discussed individually from a qualitative standpoint with regard to whether it could be a cause of IDPD. After that discussion, the overall situation is examined in light of how different courses of action cause which laws to apply different degrees of effects.
Unique acceptors for poly(ADP-ribose) in resting, proliferating and DNA-damaged human lymphocytes

Abstract Acceptor proteins for poly(adenosine diphosphoribosyl)ation were determined in resting human lymphocytes, in lymphocytes with N -methyl- N ′-nitro- N -nitrosoguanidine-induced DNA damage and in lymphocytes stimulated to proliferate by phytohemagglutinin. Kinetic studies showed that the increase in ADP-ribosylation which occurred in response to N -methyl- N ′-nitro- N -nitrosoguanidine (MNNG) treatment was greater in magnitude but more transient in duration than that which occurred in phytohemagglutinin-stimulated cells. Gel electrophoretic analyses revealed that MNNG treatment and phytohemagglutinin stimulation both caused an increase in ADP-ribosylation of poly(ADP-ribose) polymerase and core histones. In MNNG-treated cells, an increase in ADP-ribosylation of histone H1 was also observed. In contrast, phytohemagglutinin-stimulated cells showed no increase in ADP-ribosylation of histone H1. In MNNG-treated cells there was also ADP-ribosylation of a protein of molecular weight 62 000, while in phytohemagglutinin-stimulated cells there was a marked increase in ADP-ribosylation of a protein of molecular weight 96000. MNNG treatment of phytohemagglutinin-stimulated cells produced a pattern of ADP-ribosylation that appeared to be due to the combined effects of the individual treatments. 3-Aminobenzamide effectively inhibited ADP-ribosylation under all treatment conditions.
Multiple b cell stimulation by individual antigen-specific t lymphocytes.

Recently, an experimental system has been described which allows for the isolation and antigenic stimulation of individual antigen-specific helper T lymphocytes in collaboration with a nonlimiting number of primary B lymphocytes. In the studies presented in this report, this system has been employed to determine whether an individual T lymphocyte has the potential to interact with more than a single B lymphocyte, when the B cells are of different antigenic specificities. The results of these studies indicate that an individual influenza virus PR 8-specific T lymphocyte has the ability to promote antibody responses of both trinitrophenyl (TNP)- and PR8-specific B lymphocytes in response to the in vitro antigen TNP-PR8. Similar results were obtained when T cells specific for the hapten TNP were used in collaboration with TNP- and PR8-specific B cells. These results demonstrate that an individual T lymphocyte has the potential to collaborate with more than one B lymphocyte, and that these B cells may differ in their antibody receptor for antigen. These results do not rule out a role for idiotype or allotype-specific T cells in antibody responses but, rather, strongly argue that antigen-specific T cells are able to independently initiate primary B cell responses of B cells with distinct antibody receptors. In addition, under these conditions, hapten-specific helper T cells can be readily demonstrated and may facilitate the response of B cells specific for the same or different determinants.
Cloning of the murine platelet glycoprotein Ibalpha gene highlighting species-specific platelet adhesion.

Abstract ABSTRACT: We report the sequence of a 2,779 base pair genomic DNA fragment containing the mouse glycoprotein (GP) Ibα gene. Similar to its human counterpart, the mouse GP Ibα gene contains a single exon encoding a 734-residue GP Ibα precursor polypeptide. Comparative analysis between human and mouse polypeptides reveals a 75% sequence similarity between the amino-terminal domain of each polypeptide. However, there is sequence divergence within a short linear sequence of the amino-terminal domain previously implicated in human GP Ibα as critical for the binding of human von Willebrand factor (vWF). Mouse and human primary sequences diverge through their extracytoplasmic macroglycopeptide domains reducing the overall sequence similarity to 70%. The transmembrane and cytoplasmic sequences are highly conserved in both species with 59 identical residues among the 62 comprising the carboxyl-terminus of each polypeptide. The species-specific interaction between human GP Ibα and vWF was demonstrated in a model flow system monitoring the ability of surface-bound human vWF to capture from flowing blood normal mouse platelets or transgenic mouse platelets expressing the human GP Ibα subunit. The results further define structural elements necessary for the interaction of human vWF and platelets.
Liquid chromatography-tandem mass spectrometric ion-switching determination of chlorantraniliprole and flubendiamide in fruits and vegetables.

The anthranilic and phthalic diamides, chlorantraniliprole (CAP) and flubendiamide (FLU), respectively, represent a new class of very effective insecticides that activate the ryanodine-sensitive intracellular calcium release channel (ryanodine receptor). This paper reports an analytical method for the simultaneous determination of the two insecticides on fruits and vegetables by liquid chromatography−electrospray tandem mass spectrometry operated in the positive and negative ionization switching mode. The two diamides were extracted with acetonitrile and separated on a Zorbax Column Eclipse XDB C8 (4.6 mm × 150 mm i.d., 3 μm) by isocratic elution with a mobile phase consisting of acetonitrile and water with 0.1% formic acid pumped at a flow rate of 0.4 mL/min. The diamides were selectively detected by multiple reaction monitoring for transitions of proton adduct precursor ions simultaneously: positive m/z 484.3→285 for CAP, m/z 445.5→169 for internal standard, and negative m/z 681.4→253 for FLU. For CAP c...
Photoconductor-Thermoplastic Image Transducer

The photoconductor-thermoplastic, or photoplastic, recording medium can serve as an incoherent-to-coherent transducer to insert data into a coherent optical processor in real time. The photoplastic transducer is characterized by good exposure sensitivity, high resolution, and simple construction, and it is well suited to applications requiring image retention before and during readout. In our investigations we measured exposure sensitivities of less than 50 ergs/cm2 , and achieved a write cycle of charge, expose, and develop in less than 10 msec. Because of the band-pass nature of the recording medium, a spatial frequency offset was provided by overlaying the image with a grating. Images were recorded with incoherent light and read out with coherent light with good fidelity, and the transducer was tested as the input to a matched filter processor.
Year‐to‐year changes in the age structure of a caddisfly population following loss and recovery of a springbrook habitat

A severe drought in 1977 resulted in cessation of normally permanent flow m a northern California (USA) springbrook, and no individuals of the numerically dominant macroinvertebrate, the caddisfly Gumaga nigricula (McL), survived Prior to habitat loss (1976) this population was multiple cohort, two years after habitat recovery (1979) a single-cohort population was present The shift m age structure back to pre-drought conditions occurred gradually median head capsule width in 1976 (pre-drought) 0 39 mm, 1981 (post-drought) 0 95 mm, 1982 0 99 mm, 1983 0 59 mm, 1984 0 63 mm, 1985 0 63 mm, 1986 0 45 mm Age structure from 1981-1985 was significantly different (p < 0.001) from that occurring before habitat loss in 1976, age structure m 1986 was not significantly different from that in 1976 The ten-year time for return to the original population age structure could be influenced by the isolation of the springbrook from other colonization sources, gradual increases in population density, and differential growth reflecting food availability
Deconvolution of rescattering and target length effects

Abstract I have investigated a technique for quantifying effects of rescattering on final state hadron distributions. I first conduct the formalism to convolute an ideal distribution by some amount of rescattering, and then I conduct the inverse formalism to deconvolute a final distribution back to an ideal distribution. This latter technique can be used to extrapolate to zero target thickness in situations where the target length effects of rescattering are important. These techniques can also be employed to investigate the effects of nuclear targets on the final state distributions. Much of the formalism involves the use of an ideal distribution parameterized by the characteristic Feynman-field form.
Atomic absorption determination of zinc, copper, cadmium, and lead in tissues solubilized by aqueous tetramethylammonium hydroxide.

Abstract Rat liver and kidney homogenates and homogeneous rat hair samples were prepared for atomic absorption spectrophotometric analysis by digestion with an appropriate concentration of aqueous tetramethylammonium hydroxide (TMAH). The endogenous tissue levels of Zn, Cu, Cd and Pb, the reproducibility of the analyses, and the recovery of added metal standards compare favorably with the results obtained by standard wet ashing procedures using concentrated nitric acid or nitric-perchloric acids. The use of 5% HNO 3 standard curve in calculations for the TMAH-treated samples leads to slightly lower results compared to the method of additions due to viscosity and surface tension effects on the aspiration rate of these samples. Moreover, the TMAH digestion method allows faster and safer processing and handling of samples in comparison to acid digestion procedures.
Transfer of anti-DNA-producing B cells from NZB to unmanipulated xid recipients: effects of age, sex, and environment.

NZB mice have been extensively studied in an attempt to understand the pathogenesis of systemic autoimmune disease. In a recent report we demonstrated that NZB B cells would engraft and function when transferred to unmanipulated NZB.xid recipients. Anti-DNA-producing donor B cells expanded dramatically in the NZB.xid recipients. The present study examines the requirements for this expansion. We found that the age and sex of the donor were important: NZB mice less than 2 weeks of age had fewer anti-DNA-secreting precursors than did older mice; male donors had 10-fold fewer precursors than did females of the same age. An effect of the recipient environment on donor cell expansion also was noted: male recipients allowed much less expansion of anti-DNA-producing cells than did female recipients. Castration of the male recipients led to an increase in rate of expansion, suggesting that androgens played a role in regulating lymphocyte proliferation and/or activation. These studies demonstrate that anti-DNA precursors increase with age under the influence of host factors.
The equations of continuum mechanics and the laws of thermodynamics

With appropriate constitutive assumptions on the stress tensor, the heat flux vector, and the frictional heating associated to a process, we derive for a fluid media the existence of internal energy and entropy as well as the classical energy balance equation and the Clausius-Duhem inequality.
Improving the Tolerability of Anticholinergic Agents in the Treatment of Overactive Bladder

Pharmacological treatment for overactive bladder has centred around the interruption of the detrusor activity that is central to urge and incontinence symptoms. The majority of patients with this disorder are treated with antimuscarinic agents. These drugs have been demonstrated to improve urgency, frequency of micturition and urge incontinence, all of which are primary symptoms of overactive bladder; however, they are also commonly associated with anticholinergic adverse effects, most notably dry mouth. Attempts to increase tolerability have included the development of advanced formulations that regulate release of the active ingredient and the development of pharmacological agents that target the desired bladder receptors more specifically and accurately. Although all agents provide good efficacy, tolerability is greatly affected by the formulation used to deliver the active pharmacological agent, as well as the specificity of the targeted receptors. Clinical trials involving a transdermal formulation of oxybutynin have shown that this delivery method may be associated with a lower incidence of anticholinergic adverse events compared with both the immediate-release and the extended-release oral formulations of traditional agents, as well as the most recently approved agents - trospium chloride, solifenacin and darifenacin. Much is still being learned about the function and specificity of muscarinic receptors, which will support the development of agents with sustained efficacy and enhanced tolerability compared with the available formulations to date. These include the S-isomer of oxybutynin, as well as selective muscarinic M2 receptor antagonists.
Sources of Scientific Innovation: A Meta-Analytic Approach (Commentary on Simonton, 2009).

Innovations in science can be divided into at least four major types: radical revolutions (such as Copernican and Darwinian theory), technical revolutions (led by scientists such as Newton, Lavoisier, and Einstein), controversial innovations (for example, Semmelweis's theory of puerperal fever), and conservative innovations (eugenics and various vitalistic doctrines). Biographical predictors of support for scientific innovations are distinctly different depending on the type of innovation, as are the predictors of who initially engineers such innovations. A meta-analytic approach assessing each new scientific theory according to its salient features (including epistemological, ideological, and technical attributes) is required to make sense out of the varied predisposing factors associated with the origins of these innovations. These predisposing factors are not neatly classifiable in terms of Simonton's (2009, this issue) hierarchical model of domain-specific dispositions, although this model is applicab...
Network structure in bisphthalonitrile polymers

Bisphthalonitrile monomers were cured neat, with nucleophilic and redox coreactants, or in combination with a monofunctional model compound. Dynamic mechanical measurements on the resulting polymers from −150°C to +300°C turn up several differences attributable to differences in network structure. Rheovibron results were supplemented with solvent extraction, DSC, vapor pressure osmometry, and infrared spectroscopy to characterize the state of cure.
Molecular orbital study of the structure and interactions of ylidene rhodanines

Semiempirical (with the AM1 Hamiltonian) and ab initio (mainly with the 6-31G* and LANL2DZ+ +(d,p) basis sets) molecular oribital calculations show the predominant tautomer of gas phase methylidene rhodanine is 2-thioxo-4-thiazolidinone in agreement with earlier work on other types of rhodanines. Inclusion of solvation effects in the AM1 calculations corroborates with this tautomer is also preferred in aqueous solution. Energy-optimized bond lengths and angles show good agreement with those for a crystalline benzylidene rhodanine. The geometry of a hydrogen bonded dimer matches closely the crystalline state arrangement. The two N-H ⋯ O hydrogen bonds that form in the dimer. provide a stabilization energy of about - 10 kcal/mol. The interactions of methylidene rhodanine with a calcium ion are modeled with basis sets as large as LANL2DZ+ +(d,p). The preferred binding site is near the carbonyl oxygen for the neutral rhodanine and near the nitrogen and thione sulfur in a bidentate arrangement for the rhodanine anion. Implications for the interaction of benzylidene rhodanines with various possible protein and metalloprotein receptors are discussed.
Shifting the pH Profile of Aspergillus niger PhyA Phytase To Match the Stomach pH Enhances Its Effectiveness as an Animal Feed Additive

Environmental pollution by phosphorus from animal waste is a major problem in agriculture because simple-stomached animals, such as swine, poultry, and fish, cannot digest phosphorus (as phytate) present in plant feeds. To alleviate this problem, a phytase from Aspergillus niger PhyA is widely used as a feed additive to hydrolyze phytate-phosphorus. However, it has the lowest relative activity at the pH of the stomach (3.5), where the hydrolysis occurs. Our objective was to shift the pH optima of PhyA to match the stomach condition by substituting amino acids in the substrate-binding site with different charges and polarities. Based on the crystal structure of PhyA, we prepared 21 single or multiple mutants at Q50, K91, K94, E228, D262, K300, and K301 and expressed them in Pichia pastoris yeast. The wild-type (WT) PhyA showed the unique bihump, two-pH-optima profile, whereas 17 mutants lost one pH optimum or shifted the pH optimum from pH 5.5 to the more acidic side. The mutant E228K exhibited the best overall changes, with a shift of pH optimum to 3.8 and 266% greater (P < 0.05) hydrolysis of soy phytate at pH 3.5 than the WT enzyme. The improved efficacy of the enzyme was confirmed in an animal feed trial and was characterized by biochemical analysis of the purified mutant enzymes. In conclusion, it is feasible to improve the function of PhyA phytase under stomach pH conditions by rational protein engineering.
Failure of the automatic implantable defibrillator to detect ventricular fibrillation

Abstract Some of the reported problems with the use of the automatic implantable defibrillator (AID) include inappropriate discharge, 1–3 failure to defibrillate because of excessively high defibrillation thresholds 3–5 and failure to sense ventricular fibrillation (VF) in patients who also have pacemakers. 1,2 In this report, we describe another potential problem: the failure of an AID to sense VF because of variable bipolar epicardial electrogram amplitudes during VF.
Labeling of cysteine-containing peptides with 2-nitro-5-thiobenzoic acid

Abstract A method for specific labeling of cysteine-containing peptides has been developed using Ellman's reagent, 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB). Prior to cleavage with proteases or chemical reagents, proteins are reacted with DTNB, resulting in the formation of a mixed disulfide between the protein sulfhydryl group and 2-nitro-5-thiobenzoic acid (TNB). The formation of the mixed disulfide introduces a chromophore, with an absorbance peak at 328 nm. By monitoring peptide maps generated by HPLC at 210 and 328 nm, peptides containing cysteine residues are readily identified. The stability of the derivative was tested using glutathione-TNB as a model compound. Glutathione-TNB is stable to conditions used for CNBr cleavage, as well as those for tryptic cleavage. The TNB label may also increase the hydrophobicity of small peptides, which otherwise might not bind to reverse-phase matrices. This was the case for an oxidatively modified tetrapeptide isolated from Escherichia coli glutamine synthetase.
The temperature dependence of the angular variation of, and the critical point exponent for the EPR linewidth in the two-dimensional canted antiferromagnetic (C2H5NH3)2MnBr4: Evidence for a structural phase transition

Abstract The angular variation of the EPR linewidths in single crystals of (C 2 H 5 NH 3 ) 2 MnBr 4 has been measured as a function of temperature. The angular dependence is well characterized by δH ( θ ) = a + b (3 cos 2 θ − 1) + c (3 cos 2 θ − 1) 2 . The temperature dependence of the expansion coefficients is reported, and the effect of critical point fluctuations near the Neel temperature as well as a linear temperature dependence at high temperature are observed. A sharp decrease in linewidths at 160°K is attributed to a structural phase transition. The Neel temperature is determined to be 46°K (± 1°) from linewidth measurements of a powder sample. The linewidths diverge exponentially near the Neel temperature with a critical point exponent of 1.5.
Pseudochoreoathetosis : movements associated with loss of proprioception

Objective: To describe seven patients with proprioceptive sensory loss and choreoathetoid movements. Design: Case series. Setting: Outpatient and inpatient university referral. Patients: Patients with sensory loss and abnormal movements. Intervention: None. Main Outcome Measure: None. Results: One patient had a parietal cortex injury, one had a thalamic infarction, two had spinal cord lesions, two had dorsal root ganglion neuronopathies, and one had an ulnar neuropathy. In each case, the duration of abnormal movements correlated with the duration of proprioceptive sensory loss, and the abnormal movements were restricted to body parts with proprioceptive sensory loss. The movements varied from chorea and athetosis to dystonia. Conclusions: These cases suggest that proprioceptive sensory loss can lead to a movement disorder, termedpseudochoreoathetosis, which occurs following the appearance of lesions anywhere along proprioceptive sensory pathways, from peripheral nerves to the cerebral cortex. It is hypothesized that pseudochoreoathetosis occurs because of the failure to process limb proprioceptive information in the striatum. Therefore, both choreoathetosis and pseudochoreoathetosis may be manifestations of the failure of the striatum to properly integrate cortical motor and sensory inputs.
Key Donor Cultivation: Building for the Future

ABSTRACT The cultivation of key donors should be approached broadly, patiently, and carefully. One should involve a number of individuals, groups, and activities over a long but indefinite period. Important constituents include library advisory boards, past donors, and your advancement office. These constituents, along with meetings and cultural events, all go into the mix that forms the basis of an effective donor program.
Proposal for solving the "problem of time" in canonical quantum gravity.

The ``problem of time'' in canonical quantum gravity refers to the difficulties involved in defining a Hilbert space structure on states, and local observables on this Hilbert space, for a theory in which the spacetime metric is treated as a quantum field, so no classical metrical or causal structure is present on spacetime. We describe an approach, much in the spirit of ideas proposed by Misner, Kucha\ifmmode \check{r}\else \v{r}\fi{}, and others, to defining states and local observables in quantum gravity which exploits the analogy between the Hamiltonian formulation of general relativity and that of a relativistic particle. In the case of minisuperspace models, a concrete theory is obtained which appears to be mathematically and physically viable, although it contains some radical features with regard to the presence of an ``arrow of time.'' The viability of this approach in the case of infinitely many degrees of freedom rests on a number of fairly well-defined issues, which, however, remain unresolved. As a by-product of our analysis, the theory of a relativistic particle in curved spacetime is developed.
Population genetic diversity and structure within and among disjunct populations of Alnus maritima (seaside alder) using microsatellites

Small, isolated populations are prone to genetic drift and high levels of inbreeding that can threaten their long-term survival. Alnus maritima persists exclusively in three groups of small, highly disjunct, regional populations in the Delmarva Peninsula, Georgia, and Oklahoma. Trees in the three regions are recognized as separate subspecies. Microsatellite markers were used to measure fine-scale population genetic diversity and structure (1) within and among regions and (2) within and among populations in each region. Compared to a previous study utilizing allozymes, microsatellite data show higher levels of variation, lower levels of inbreeding, but similar levels of genetic differentiation among regions. Significant genetic differentiation was detected among regions and among distinct populations within regions. Genetic differentiation was significantly correlated with geographic distance among regional populations, but not among populations within regions. Populations, therefore, likely represent fragments of formerly extensive networks of populations that have decayed and retracted due to competition with other species better adapted to the shadier habitats of late-succession environments. The unique genetic features of populations within different regions should be considered as part of future conservation efforts.
Linewidths observed in a Zeeman scanned laser amplifier

Abstract The phenomena of gain narrowing and saturation broadening of the Doppler broadened 3.39 μ neon line have been observed in stimulated emission. The observed frequency profile of the unsaturated gain for plane polarized input is in good agreement with previously derived expressions for the narrowed linewidth so long as output is not polarization analyzed. In this case, the gain linewidth is narrowed to one third the Doppler width for the highest gain obtained. Plane polarization analysis of the amplified beam yields even further narrowing to 15% of the Doppler width and is understood by a theory of gain narrowing due to Corney. Although the reported data are of insufficient accuracy to determine the radiative linewidth of the transition, an upper bound on the radiative width is estimated to be 36 MHz or less.
The 147 nm photolysis of phosphine—silane mixtures

Abstract The 147 nm photochemistry of PH3SiH4 mixtures was investigated at various ratios of the substrates such that more than 90% of the radiation was absorbed by PH3. The photodecomposition of PH3SiH4 mixtures results in the formation of H2, Si2H6, PH2SiH3 and P2H4 in the gas phase and a solid deposit which is probably a mixture of phosphorus and polymeric phosphorus silicon hydrides PSiHx. On photolyses of mixtures of the deuterated derivatives the analogous deuterated products are formed. The quantum yields for the gaseous products and for depletion of the substrates were measured. For the PH3SiH4 system it was found that quantum yields depend on the composition of the reactant mixture and on the light intensity of the incident radiation. When deuterated compounds were used significant changes in all quantum yields were observed. Parent-ion mass spectrometric analysis of phosphorus- and silicon-containing volatile products indicates that PH2SiH3 is formed by two pathways: (i) combination of PH2 and SiH3 radicals; (ii) insertion of SiH2 into PH3. A mechanism involving primary photodissociation of PH3 is proposed which is in accord with the experimental observations as well as with our knowledge of the photochemistry of pure PH3 and SiH4.
Relative-price variability in the United States

Abstract Following the Clements-Nguyen methodology, relative-price variability in the United States is decomposed into the components due to real factors, inflation, and their interaction. Overall, inflation accounts for about half of relative-price variability, but its share is the largest during 1973–1980 and the smallest during 1981–1986. Cross-commodity distribution of relative-price variability shows rather dramatic changes.
Temporal instabilities in an externally driven ring phase conjugator

A ring self-pumped phase-conjugator mirror with an injected signal and an applied external electric field was studied in an experiment with a photorefractive strontium barium niobate crystal. Competition between the injected signal and free oscillation caused temporal instabilities in the output beam. Periodic and erratic pulsations of output intensity were observed as a function of the injected beam intensity and electric field strength. Numerical simulations of the theoretical model of this system confirmed the existence of the regime of unstable behavior.
Palaeoclimates at Lake Turkana, Kenya, from oxygen isotope ratios of gastropod shells

Climatic changes in the Plio-Pleistocene of East Africa during the evolutionary development of early man have been identified only in their broadest outlines. A variety of palaeontological1–3 and geochemical4 techniques have already been applied to the study of palaeoclimates in this area, but the use of stable oxygen isotope ratios, so helpful in marine palaeoclimatology, has not been fully exploited5,6. The frequent occurrence of well-preserved mollusc shells in the sedimentary column at Lake Turkana provides a sensitive oxygen isotope record, varying over a range of 7‰, which can be interpreted in terms of evaporative concentration of the heavier oxygen isotope in waters of the closed lake, alternating with isotopically lighter freshwater when the lake has been open. I report here the results of a study of the 18O/16O ratios of three species of gastropods from the sediments of the Koobi Fora region of Lake Turkana, and evaluate how the technique might be applied to the study of the palaeoclimates of other tropical lakes.
A thermodynamics and physical properties package (TAP)

Abstract Transport and thermodynamic properties such as viscosity, thermal conductivity, enthalpy, etc., are frequently needed in chemical process computations. A computer program was written which calculates these and many other related properties rapidly and efficiently. The system consists of an executive program called ROADMP plus 41 subroutines. ROADMP decides what subroutines must be used to calculate a given property from input data provided by the user. All the subroutines, except ROADMP, consist of small programs that use well-established physical property correlations. Extensive tests and error checks were made and are included, where possible, in the system. The entire program consists of 3200 FORTRAN statements and occupies 11K of memory.
Google Insights and U.S. Senate Elections: Does Search Traffic Provide a Valid Measure of Public Attention to Political Candidates?†

Objective To propose a new indicator of public attention to electoral candidates based on the relative pattern of Internet queries for opposing candidates. Methods To demonstrate the validity of this measure, we use ordinary least squares regression and an F-ratio test. Results We find that this measure, based on Google Insights data, behaves in a manner consistent with a valid measure of public attention. Moreover, this finding holds when the measure is included in a standard model used to explain U.S. Senate election outcomes. Conclusion The Google Insights measure of relative public attention shows the shifts in public attention as the campaign is waged and is consistent with how we would expect to see such a measure behave. This research opens numerous avenues for research in the campaigns and elections subfield.
Altered States: Explaining Domestic Institutional Change

Existing explanations of domestic structural change focus on the role crises play in precipitating radical or episodic change. They largely ignore the sources and consequences of incremental change, even though this type of change also can have significant effects for policy processes and outcomes. We outline a framework for studying institutional transformation that accounts for both forms of change. The argument is a three part one. First, international and domestic events, including both crises and gradual pressures, open windows of opportunity that provide policy officials with the potential to transform existing institutions. Large-scale, system-wide changes open large windows, which allow radical change, while small-scale, issue-specific problems and changes create more limited opportunities for change. Secondly, whether an institutional change follows a window of opportunity depends on the actions and interests of state officials. Thirdly, state officials' ability to capitalize on a window of opportunity depends on their institutional position or capacity; the prevailing institutional arrangements create opportunities for, or place limits on, officials' ability to make change. Two case studies illustrate and probe the plausibility of the argument.
Reflecting Coatings for the Extreme Ultraviolet

The conditions for preparing evaporated Al films of highest reflectance for mirrors and gratings to be used in the vacuum ultraviolet are summarized, and an account is given of aging studies. The preparation of bloom-free, one-micron thick coatings for grating blanks is described, and the effect of thin overcoatings on the efficiency of ruled gratings is discussed. Data are presented on the reflectance and aging of other film materials, such as Pt, ZnS, and Al2O3, which are more suitable for use at wavelengths below 1200 A. A discussion is given of the preparation and the reflecting properties of various multilayer film combinations suitable for reducing the reflectance of mirrors and gratings in the visible and the near ultraviolet while at the same time preserving a high reflectance in the extreme ultraviolet. A 250-A thick layer of MgF2 evaporated onto an Al coating immediately after its deposition was found both to raise the reflectance to about 80% at wavelengths down to 1200 A, and to retard aging.
Using burst recovery concept to obtain global stability and performance of discrete-time adaptive controller for time-varying systems

In this note, a new technique is proposed for the global stability analysis of adaptive control of time-varying systems. The proposed method is based on the evaluation of possible burstings in the adaptive loop. Its simplicity and effectiveness is demonstrated by analyzing global stability and performance of the discrete-time direct adaptive controller. The developed technique reflects physical phenomena inside the adaptive loop, i.e., possible occurrence of instabilities and burstings. Precise upper bounds on the admissible speed of the parameter variations and on all the signals are established in terms of clearly defined physical quantities. >
Integration of technology incubator programs with academic entrepreneurship curriculum

Engineers are excellent sources of high growth-potential entrepreneurial ventures, with their creative product and technology ideas. However, this resource has not been effectively tapped by academia in general. This paper reviews entrepreneurship, the debates over teaching entrepreneurship and critical success factors for new venture creation. Also described is an innovative, holistic inter-disciplinary engineering entrepreneurship program backed by the resources and activities of a technology incubator. This provides engineering students and researchers with tools and opportunities for entrepreneurial success, establish deeper and more meaningful community ties, and facilitate the incubation of investable technology-based start-ups. Packaging the "incubator concept" into a series of graduate, undergraduate and continuing education short courses is a unique feature of UCF's entrepreneurship program, which offers practical insights, tools, objectives, case studies, strategies and actions that one can apply to any stage of an entrepreneurial or intrapreneurial venture from initial idea to growth and profitability. Guest lectures and interaction/networking opportunities with successful or struggling technical entrepreneurs, corporate intrapreneurs, angel investors, venture capitalists, technology incubator directors, attorneys, financial advisors, consultants, and other business service providers are added benefits of this program. This program has received very favorable reviews from local, state and national organizations.
Hydrocarbon pollutants alter short-term recruitment in the barnacle Balanus eburneus

Abstract We examined barnacle recruitment to oil-treated clay tiles at two coastal and two protected sites along the Louisiana coast. Tiles exposed to crude oil and its water-soluble fraction (WSF) had diminished barnacle recruitment after 3 weeks, in comparison with non-treated tiles. Effects were most obvious at the exposed coastal sites. After a 6-week immersion, however, treatment effects were no longer consistent. In later experiments, Balanus eburneus recruitment was higher on weathered WSF tiles (exposed, and leached in seawater before immersion in the field) than on WSF tiles, but not different from control tiles. Hydrocarbons depress recruitment initially, but may be removed later by leaching or by hydrocarbon-degrading microbes, and the remaining biofilm may facilitate recruitment. While barnacle recruitment was generally higher at exposed sites, as expected from the literature, local factors caused significant variation in recruitment within exposure categories as well. Barnacles also grow to larger sizes at open-coast sites, probably because of increased water flow and planktonic food delivery. Naupliar abundances varied tremendously among sites and dates and were poor predictors of eventual recruitment.
Centrifugal microfluidic platform for rapid PCR amplification using integrated thermoelectric heating and ice-valving

a b s t r a c t We present a novel centrifugal microfluidic system for the rapid amplification of a Bacillus anthracis gene, with integrated pumping and thermoelectric-based heating and valving. Polymerase chain reaction is a powerful method for rapid and accurate diagnosis of infectious diseases and bio-warfare agents. The fully integrated system and disposable disc developed here automates the fluidic pumping, valving, and rapid thermocycling required for polymerase chain reaction. We demonstrate the first utilization of ice-valving in an integrated centrifugal microfluidic system as a method for sealing the thermocycling chamber to reduce fluid loss due to evaporation. The automated centrifugal system is validated via amplification of a B. anthracis gene. Fluidic thermal profiles are monitored and optimized to minimize non-specific amplification, reducing the total amplification time from 110 min down to 53 min.
Performance Quality Improvement Projects: Suggestions for Interventional Radiologists

m s T g p t v a i e T b d c m Interventional radiology (IR) is surrounded by complex processes and potential quality issues that can affect the ability to ensure optimal patient care. Interventional radiology combines all the challenges of an operating theater with the challenges of implementing highly advanced imaging technologies. In spite or perhaps because of the large number of issues that affect these practices, it is often difficult to decide how to start an interventional quality project. Often, we resign ourselves to a chaotic environment and then try the best we can to serve patients. How then does one scope out a project that can gain traction? As a start, some good generic guidelines for quality improvement projects can be found in the National Quality Forum’s guidelines [1]. These criteria are intended to evaluate the effectiveness of a quality measurement but can also provide insight into thinking about solid quality projects.
Current Trends in Online Language Learning

Online language learning (OLL) can take place in Web-facilitated, hybrid, or fully virtual classes. These formats are beginning to attract serious attention from the language profession and, in particular, the field of computer-assisted language learning (CALL). This article traces recent studies of online learning and then focuses in on its application to language learning through tutorial CALL, social computing, and games for language learning. I strive to show that tutorial CALL and computer-mediated communication can complement each other in the service of modern language instruction, along with the inclusion of language games. Although assessment studies of OLL remain sparse, the evidence is steadily mounting that shows that these new formats can provide learning environments conducive to successful second language development when properly integrated into the curriculum.
Roles of EphA2 in Development and Disease

The Eph family of receptor tyrosine kinases (RTKs) has been implicated in the regulation of many aspects of mammalian development. Recent analyses have revealed that the EphA2 receptor is a key modulator for a wide variety of cellular functions. This review focuses on the roles of EphA2 in both development and disease.