cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis and characterization of membrane stable bis(arylimino)isoindole dyes and their potential application in nano-biotechnology.

A synthetic methodology of preparing novel membrane stable, responsive dyes is revealed in this manuscript. 1,3-Bis(arylimino)isoindole dyes were synthesized and their properties to undergo intramolecular hydrogen bonding was studied with fluorescence spectroscopy in varying solvent polarities. Based on the functional moieties, compound that is capable of hydrogen donor and acceptor interactions produces predominant photoexcitation in comparison to the responsive dyes that lack these functionalities. These dyes, by the virtue of the presence of long chain acyl groups could be incorporated stably within the phospholipids membrane of core-shell nanoparticles. Nanoparticle was ‘cracked’ to release the dye from a hydrophobic to a hydrophilic environment. A significant change in florescence intensity was then observed, indicating the direct change in effect of intramolecular hydrogen bonding based on solvent polarity changes. This unique study provided implications of many further applications toward nanomedicine and nano-biotechnology.
Light dosimetry for photodynamic therapy in the esophagus

Evaluating the light distribution in the esophagus is central to understanding how to optimize treatment of Barrett's esophagus with PDT. The light distribution of a cylindrical light diffuser in the esophagus was investigated by Monte Carlo simulations and experiments in esophageal simulating phantoms. Simulation of light transport in the esophagus requires knowledge of several biological parameters including radius, height, mucosal wall thickness and optical parameters such as reduced scattering coefficient, absorption coefficient, scattering anisotropy and refractive index. Results of Monte Carlo simulations were tested by measuring the light fluence rate in an esophagus phantom (absorption coefficient = 0.27 mm -1 , reduced scattering coefficient = 1.9 mm -1 , g = 0.9, n= 1.37) irradiated at 633nm with a 5cm long cylindrical light diffuser. We evaluated the light distribution within the esophagus for the on-axis and off-axis treatment fiber conditions both experimentally and mathematically. Results showed the reflected light from the walls of the esophagus increased the incident light dose at all points being treated by a factor of 1.6, compared to the dose given off by the fiber itself. Also, when the fiber was moved from one side of the esophagus to the other, it increased the light dose to the proximal area by a factor of 2, and decreased the light dose to the distal region by a factor of 2 in the phantom study, and in Monte Carlo simulation, factor of 18 and factor of 3 respectively.
Design of Brewery Pasteurization Method by High Pressure Carbon Dioxide

The compressed CO2 was supplied from the CO2 cylinder to the steel vessel containing yeast-water mixture until the pressure inside the steel vessel reached a desired pressure level. The steel vessel was kept at the prescribed pressure level during the treatment period. After the treatment, the pressure inside the vessel was released to the atmospheric pressure within the evacuation time by controlling the relief control valve. The sterilization effect was evaluated by vial counting the treated sample taken from the steel vessel. Several experiments have been performed varying each factor such as the total treatment time, the evacuation time and the applied pressure. As a result, it was verified that these factors are strongly related to the sterilization effect. In addition, it was observed that increase of the treatment time could enhance the concentration rate of CO2 in the mixture. Furthermore, it was concluded that fast depressurizing rapidly expanded CO2 penetrated into each yeast cell. Also, the experimental results showed that when treatment time is longer, the pressure becomes higher, and the evacuation time is shorter, thus, a better sterilizing effect was obtained. Contrary to the results above, both the treatment time and the evacuation time rarely affected sterilization effect under supercritical condition. By adopting Supercritical condition, a desirable result could be achieved with shorter treatment and longer evacuation time. Thus, as long as supercritical condition is adopted for test, either fast evacuation time or long treatment time is not essential any more.Copyright © 2005 by ASME
Profiles of School Administrators in South Korea: A Comparative Perspective.

Research literature considering school administrators in South Korea is disappointingly sparse. A central focus of this article is to investigate vital descriptors of Korean school administrators, including demographic profiles, entry perspectives, pre-service and in-service training and career commitment. Secondarily, the findings are compared to research conducted by Su et al. of school administrators in the USA and China. Using survey data collected from over 400 South Korean administrators, this study makes international comparisons, and at the same time, exposes the unreflective tendency to lump together nations and systems based on ethnic or geographic distinctions. The study highlights the present and vital need for South Korea to redefine its educational system and practice as the national identity moves toward a new equilibrium that reconciles tradition and (post-) modernity.
The Crises of Marxism in Post-Positivist Perspective:

Drawing on post-positivist discourse within the philosophy of science, this paper argues that the phenomenon known as the "crisis of Marxism" is really two distinct phenomena. One is a crisis internal to the irregular series of theories identified with Marxism, a crisis marked by a partial degeneration of the research program, a slowing in its problem-solving effectiveness. The other is a crisis in the community bound by the Marxist disciplinary matrix.
ON THE CALIBRATION OF LONGITUDINALLY SEGMENTED CALORIMETER SYSTEMS

Abstract Most calorimeter systems used in particle physics are longitudinally segmented in two or more compartments. The intercalibration of these compartments is highly non-trivial, as a result of two effects: (1) The dependence of the calorimeter response on the type of showering particle, and on its energy. (2) The depth dependent sampling fraction in showers. A variety of methods that are used in practice to deal with these problems are reviewed. The (lack of) merits of these methods are discussed.
Facilitation of female sexual behavior in male rats by septal lesions: an interaction with estrogen.

Abstract Although destruction of the septal region markedly facilitates the lordosis behavior of female rats in response to estrogen priming, comparable lesions were found to be ineffective in facilitating the lordotic behavior of estrogen primed male rats. Neither the age at the time of septal destruction nor castration influenced the lordosis behavior of males. However, if prepubertal castrated males were given subcutaneous ovarian grafts or injected daily with 2 μgm estradiol benzoate (EB) during the 30 day period following septal destruction, a prolonged facilitation of the activational effects of EB on lordosis behavior was observed. Male rats subjected to septal destruction alone, chronic exposure to EB alone, exposure to ovarian grafts for 30 days prior to septal destruction, or chronic treatment with EB started 6 mo after septal lesioning, failed to show an increase in behavioral responsiveness to estrogen. Thus, in order for septal lesions to facilitate lordosis behavior of male rats, exposure to EB or ovarian tissue must occur within an apparent critical period following septal destruction. Adult male rats were found to be more responsive to this interaction of septal lesions and EB exposure than pubertal animals. It is suggested that the prolonged facilitation of lordosis behavior which follows septal destruction and estrogen exposure in the male rat may be due to hormonal modifications of the recovery process following brain damage.
Chloropicrin dechlorination in relation to toxic action.

Chloropicrin (CCl3NO2) is a widely used soil fumigant with an unknown mechanism of acute toxicity. We investigated the possible involvement of dechlorination in CCl3NO2 toxicity by considering its metabolism, inhibition of pyruvate and succinate dehydrogenases, cytotoxicity in cultured cells, and interaction with hemoproteins. In a newly discovered pathway, CCl3NO2 is metabolized to thiophosgene, which is characterized as the cyclic cysteine adduct (raphanusamic acid) in the urine of mice. CCl3NO2 inhibits porcine heart pyruvate dehydrogenase complex (IC-50 4 μM) and mouse liver succinate dehydrogenase complex (IC-50 13 μM), whereas its dehalogenated metabolites (CHCl2NO2 and CH2ClNO2 are more than 10 times less effective. The inhibitory potency of CCl3NO2 for these dehydrogenase complexes is similar to that of captan, folpet, and dichlone fungicides (IC-50 2–6 μM). CCl3NO2 cytotoxity with Hepa 1c1c7 mouse hepatoma cells (IC-50 9 μM) is not correlated with glutathione depletion. Mice treated intraperitoneally with CCl3NO2 at 50 mg/kg but not with an equivalent dose of CHCl2NO2 show increased concentrations of oxyhemoglobin in liver. The acute toxicity of CCl3NO2 in mice is due to the parent compound or metabolites other than CHCl2NO2 or CH2ClNO2 and may be associated with inhibition of the pyruvate dehydrogenase complex and elevated oxyhemoglobin. © 1999 John Wiley & Sons, Inc. J Biochem Toxicol 14: 26–32, 2000
The effect of trailing end geometry on the vibration of a circular cantilevered rod in nominally axial flow

Abstract The effect of “trailing end” geometry on the vibration of a circular cantilevered rod in nominally axial water flow is reported. Eleven different trailing end geometries were tested. For each end geometry, rms displacement response and damping were measured and are presented as functions of mean axial flow velocity. The various geometric end shapes are ordered according to their effectiveness in attenuating rod vibration. The results, which are in qualitative agreement with similar experimental results from tests on flat plates, provide the designer with empirical information that allows selecting a trailing end geometry that minimizes response to parallel flow excitation. The results have application in the design of nuclear reactor fuel pins and certain instrumentation probes.
"Facebook is a luxury": an exploratory study of social media use in rural Kenya

Facebook use is pervasive in developed countries where computers, smartphones, high-bandwidth Internet, and electricity are ubiquitous. In this paper, we examine Facebook use in a country where social media participation is growing, but less developed technological infrastructures and uneven access to technology limit use. We conducted observations and 24 interviews at Internet cafes in rural Kenya. Our findings reveal how costs associated with using the Internet, limited access to computers and smartphones and unreliable electricity hinder online participation. We draw on these results to discuss the critical role of constraints in understanding social media use, to raise questions about broadening online participation and to highlight ethical issues researchers must consider when studying Facebook use in developing regions.
The effect of incubation media on the water exchange of snapping turtle ( Chelydra serpentina ) eggs and hatchlings

The effect of two different incubation media, sand and vermiculite, on the water exchange of eggs and the mass of hatchlings of snapping turtles (Chelydra serpentina) was assessed. The eggs were incubated fully buried in either sand or vermiculite at 30 °C and egg mass was measured periodically throughout incubation. The wet and dry masses of each hatchling and its residual yolk were measured at the end of incubation. The media had similar water potentials (Ψ) but their thermal conductivities differed 2.8-fold. The eggs experienced a net water gain during incubation. The rates of water uptake between treatments were not statistically different throught the first 36 days of incubation but were statistically different thereafter, with eggs incubating in sand taking up water at about twice the rate of eggs incubating in vermiculite. Hatchling masses were similar to both media but hatchling water contents were significantly different. Hatchlings incubated in sand had lower water contents than hatchlings incubated in vermiculite even though the eggs in sand took up more water. Hatchling mass was correlated with egg water exchange for eggs incubated in vermiculite but not for eggs incubated in sand. The difference in egg water exchange in the two media appears to be attributable to differences in the thermal conductivity of the media. The presence of such a thermal effect supports the hypothesis that the eggs exchanged water with the media as water vapor. Egg water exchange was limited by the shell and shell membranes and not by the media. The shell and shell membranes appear to present an effective barrier to water uptake.
Remote sensing and large‐scale global processes

This symposium was held May 18–19 as part of the International Association of Hydrological Sciences Third Scientific Assembly in Baltimore, Md. Sponsored by the International Committee on Remote Sensing and Data Transmission (ICRSDT), the symposium was well attended, with some sessions having over 100 participants. Five sessions were held, covering the topics of large-scale processes; evapotranspiration; precipitation; ice, snow, and climate; and remote sensing, with a total of 19 papers presented. All authors were present, and all papers were prepublished as IAHS Publication 186, price $40. In addition, a poster paper session was held.
Epigenetic mechanisms in developmental programming of adult disease

Adverse insults during intrauterine life can result in permanent changes in the physiology and metabolism of the offspring, which in turn leads to an increased risk of disease in adulthood. This is an adaptational response by the fetus to changes in the environmental signals that it receives during early life to ensure its survival and prepare itself for postnatal life. Increasing evidence suggests that the epigenetic regulation of gene expression patterns has a crucial role in the developmental programming of adult disease. This review summarizes recent studies of epigenetic mechanisms and focuses particularly on studies that explore identifiable epigenetic biomarkers in the promoters of specific disease-associated genes. Such biomarkers would enable early recognition of children who might be at risk of developing adult disease with fetal origins.
Problem Identification and Task Engagement Using the LIBRE Problem Solving Tool: A Case Study of Three Bilingual Teacher Candidates

Bilingual Latino students engage multiple languages, cultures and environments as they pursue educational and professional goals. For this underrepresented group, pursuing a post-secondary degree is a “ lucha ” (fight) to negotiate the complex interplay of historical, educational, and cultural variables and achieve academic success. Because Bilingual Latino teacher success is incumbent upon successfully negotiating and overcoming linguistic, cultural and educational challenges, examination of problem solving and goal setting is necessary to provide insight into the types of barriers and facilitators that this group experiences and the ways in which they overcome obstacles. An in-depth case study of three bilingual teacher candidates illustrates the use of the LIBRE problem-solving tool as a culturally responsive activity involving a sequence of problem identification, analysis, solution generation, and evaluation to facilitate problem resolution. The case studies examined herein illuminate self-reported social-cultural contextual challenges, solutions, goals, and engagement through explicit problem solving and shows the primacy of familia and cultura in these women’s lives, problem-solving, and decision making. Implications for teacher educators and bilingual Latino teacher candidates are discussed.
Multistate structural modeling and voltage-clamp analysis of epilepsy/autism mutation Kv10.2-R327H demonstrate the role of this residue in stabilizing the channel closed state

Voltage-gated potassium channel Kv10.2 (KCNH5) is expressed in the nervous system, but its functions and involvement in human disease are poorly understood. We studied a human Kv10.2 channel mutation (R327H) recently identified in a child with epileptic encephalopathy and autistic features. Using multistate structural modeling, we demonstrate that the Arg327 residue in the S4 helix of voltage-sensing domain has strong ionic interactions with negatively charged residues within the S1–S3 helices in the resting (closed) and early-activation state but not in the late-activation and fully-activated (open) state. The R327H mutation weakens ionic interactions between residue 327 and these negatively charged residues, thus favoring channel opening. Voltage-clamp analysis showed a strong hyperpolarizing (∼70 mV) shift of voltage dependence of activation and an acceleration of activation. Our results demonstrate the critical role of the Arg327 residue in stabilizing the channel closed state and explicate for the first time the structural and functional change of a Kv10.2 channel mutation associated with neurological disease.
Pressure build-up during CO2 storage in partially confined aquifers

Abstract Geologic CO 2 sequestration in saline aquifers is an attractive option for GHG mitigation, but an associated risk is pressure buildup in the aquifer, which could increase the probability of fracturing the seal or activating a fault. We report on a series of simulations to quantify this risk factor. This work also evaluates injectivity limitations from the “backpressure” at sealing faults, a potentially important factor in assessing the number of wells (and hence the cost) needed for storage. We simulate injection of CO 2 at rates and durations appropriate for capture from coal-fired power plants. The target formations are deep saline aquifers partially confined by faults. We inject at fixed rate, subject to an upper bound on the injection pressure; none of the simulations shown here reach this threshold. Compositional (Peng–Robinson equation of state) simulations are carried out with CMG’s GEM reservoir simulator with different locations and geometries of sealing faults in aquifers, with several values of rock compressibility. We evaluate two parameters: CO 2 injectivity vs. time, and pressure profile in the aquifer. From the latter we obtain a risk parameter defined as the location of a contour of 50 psi above hydrostatic. Such a parameter is suitable for inclusion in a Certification Framework for geologic storage ([C.M. Oldenburg, S.L. Bryant, J.-P. Nicot, N. Kumar, Z. Yingqi, Certification framework based on effective trapping for geologic carbon sequestration (abs.), in: Seventh Annual Conference on Carbon Capture & Sequestration: Addressing the knowledge, policy, regulatory and technology gaps to expedite CCS deployment, Pittsburgh, Pennsylvania, May 5–8, Abstract #817, 2008.)]. A single sealing fault has little influence on injectivity as long as it is beyond the radial extent of the CO 2 plume. Rock compressibility has negligible influence on injectivity and pressure contours. As the number or proximity of faults increases, the injectivity decreases slightly. In contrast to injectivity, contours of elevated pressures are sensitive to faults. They extend farther as the number or proximity of faults increases, increasing the area of influence and thus the risk of failure (seal fracture, fault activation) significantly. Thus well placement relative to known faults is an important design consideration. The effect of aquifer depth on pressure build-up due to injection is also investigated. The variation of fluid viscosity with pressure and temperature (brine viscosity is much more sensitive than CO 2 viscosity) is the dominant effect on injectivity and pressure build-up. An important overall message is that contours of elevated pressure extend much farther into the aquifer than the CO 2 plume itself. Thus risk assessment that focuses exclusively on CO 2 may underestimate actual project risk.
Preferential derivation of abnormal human G-group-like chromosomes from chromosome 15

The marked binding of antibodies specific for 5-methylcytidine to the short arm of chromosome 15 distinguishes this chromosome from the other human acrocentrics. This method has been used to study over 60 individuals including 12 who did not have Down's syndrome, but who did have an extra G-group sized acrocentric chromosome. In six cases the extra chromosome did not show intensive binding of anti-5-methylcytidine. In the other six cases, the extra chromosome contained a 5-methylcytidine rich band at each end indicating that both ends were derived from chromosome 15 and contained centromeric heterochromatin normally present on the short arm of chromosome 15. The duplication of short arm material in the abnormal chromosomes was confirmed in all cases by quinacrine staining, nucleolar organizer (Ag-AS) staining or C-banding. In three cases, the abnormal chromosome appeared to arise from two different chromosomes 15. Several possible mechanisms for the production of the abnormal chromosome are discussed. The individuals with this abnormal chromosome all showed some degree of mental retardation, but few common physical findings.
Spectral and magnetic interplay in quantum spin chains: Stabilization of the critical phase due to long-range order.

The anisotropic quantum XY spin chain in a modulating magnetic field incommensurate with the periodicity of the chain is studied. Using Jordan-Wigner transformation, the model is mapped to a tight-binding model in fermions. In the absence of symmetry-breaking terms, the fermion model is identical with the well-known Harper equation exhibiting extended and localized phases with the onset of transition being a critical point with fractal spectrum and wave functions. The effect of O(2) symmetry breaking is to fatten the critical point resulting in a critical phase with power-law localization existing in a finite window of size determined by the anisotropy. In this three-phase spectral diagram, the transition from critical to localized phase is accompanied by the magnetic transition to long-range order. Furthermore, the scaling properties of the fractal spectrum vary in the critical phase. This leads to interesting consequences on the low-temperature thermodynamical properties of the system.
On assumptions associated with ΔKeff and their implications on FCG predictions

Abstract In this paper, an assessment of commonly used assumptions associated with Δ K eff and their implications on FCG predictions in light of existing experimental and numerical data is presented. In particular, the following assumptions are examined: (1). Δ K eff fully describes cyclic stresses and strains at the crack-tip vicinity. (2). K op can be determined experimentally or numerically with certain accuracy. (3). Overload alters K op but not K max and associated σ max at the crack-tip ‘process zone’. (4). Contact of crack faces curtails the crack driving force in terms of Δ K eff . The analysis indicates that there is insufficient support to justify the above assumptions. In contrary, the analysis demonstrates that a two-parameter fatigue crack driving force in terms of Δ K and K max , which accounts for both applied and the internal stresses should be used in FCG analyses and predictions.
Partial Correlations in Regression Computations

Abstract The partial correlation between the dependent variable and the k-th independent variable in a regression can be calculated simply from the k-th regression coefficient and its standard error. Partial correlations are useful in determining relations among the estimates obtained under alternative assumptions about which variables in a regression are independent of the disturbances.
Advanced Scientific Computing in BASIC With Applications in Chemistry, Biology, and Pharmacology

(1990). Advanced Scientific Computing in BASIC With Applications in Chemistry, Biology, and Pharmacology. Technometrics: Vol. 32, No. 4, pp. 464-465.
DNA (Cell Number) and Protein in Neonatal Brain: Alteration by Maternal Dietary Protein Restriction

Female rats were maintained on 8 or 27 percent protein diet by a pair-feeding schedule for 1 month before mating and throughout gestation. The brains of newborn rats from females on the 8 percent protein diet contained significantly less DNA and protein compared to the progeny of the females on the 27 percent diet. The data on DNA indicate that there are fewer cells; the protein content per cell was also lower. If, at birth, the brain cells are predominantly neurons, and their number becomes final at that time, then such dietary restriction may result in some permanent brain-neuron deficiency. This quantitative alteration in number as well as the qualitative one (protein per cell) may constitute a basis for the frequently reported impaired behavior of the offspring from protein-deprived mothers.
A solvent problem in barbiturate determinations

Abstract Two common problems in the quantitative determination of serum barbiturate are described, and methods of elimination of errors engendered by them are suggested. A substance present in the chloroform used to extract serum for barbiturate distorts the difference spectra graphed. This interferes with both qualitative identification of the therapeutic barbiturate class as well as the concentration of barbiturate found. A simple wash of the chloroform by the same alkali used in the back-extraction process suffices to remove this interference. Testing the reagents, which really only represents a reagent blank, quickly identifies whether a reagent problem exists. Another problem arises owing to the normally alkaline pH of serum at room temperature. It can be solved preferably by acidification, or else the ratio of extractant volume to serum volume should be increased, or two extractions of the sample must be carried out (7).
Inhibition of 25-hydroxyvitamin D 1α-hydroxylase by renal mitochondrial protein kinase-catalyzed phosphorylation☆

Abstract Partially purified chick kidney mitochondrial Type II protein kinase catalyzes the phosphorylation of 1α-hydroxylase cytochrome P-450 without affecting the rate of product formation in vitro when 1α-hydroxylase activity is reconstituted by the addition of [ferredoxin] and [ferredoxin reductase] to the phosphorylated cytochrome. The cytochrome's effective concentration, or its general spectral properties did not change upon phosphorylation. However, when the cytochrome and its ferredoxin were present simultaneously during the phosphorylation reaction, reconstitution of 1α-hydroxylase activity by the addition of ferredoxin reductase failed to catalyze product formation. Although a several fold increase in the kinase activity could be demonstrated in the presence of cAMP, the above phosphorylation effects appear to be cAMP-independent.
Using National Surgical Quality Improvement Program (NSQIP) data for risk adjustment to compare Clavien 4 and 5 complications in open and laparoscopic colectomy

Laparoscopic colectomy has been associated with fewer postoperative complications than open colectomy. However, it is unclear whether this is true for the most severe complications typically requiring treatment in an intensive care unit (ICU). The authors hypothesized that laparoscopic colectomy patients have fewer of the most severe complications even after adjustment for comorbidity risk. Using the National Surgical Quality Improvement Program (NSQIP) public use files for 2005–2008, the authors identified all laparoscopic (n = 12,455) and open (n = 33,190) colectomies by current procedural terminology (CPT) code. Using the Clavien classification for postoperative complications, they identified NSQIP data points most consistent with Clavien grade 4 complications requiring ICU care (postoperative septic shock, postoperative dialysis, pulmonary embolism, myocardial infarction, cardiac arrest, prolonged ventilatory requirements, need for reintubation) or grade 5 complication (mortality). Statistical analysis was performed using SPSS software. Odds ratios were calculated to compare laparoscopic and open colectomy regarding the probability of having any Clavien class 4 or 5 complication. Logistic regression was performed to account for the effect of preoperative conditions (American Society of Anesthesiology class, wound class, gender, preoperative functional status, preoperative albumin level, azotemia, thrombocytopenia, emergency case, and age >70 years) on complications. The univariate odds ratio showed a 2.27- to 5.52-fold greater likelihood that a patient would have a complication requiring ICU admission if open rather than laparoscopic surgery was performed (p < 0.001). Multivariate logistic regression accounting for preoperative comorbidities that might affect outcome showed persistence of an increase in complications, with an odds ratio range of 1.63 to 2.21. Evaluation of the NSQIP database demonstrated that laparoscopic colectomy confers an independent protective effect on the frequency of ICU-level (Clavien grade 4) complications and mortality. The protective effect remained evident after correction for preoperative conditions that might have affected outcome.
Accessing nonlinear phase contrast in biological tissue using femtosecond laser pulse shaping

Nonlinear imaging takes advantage of the localized nature of the interaction to achieve high spatial resolution, optical sectioning, and deeper penetration in tissue. However, nonlinear contrast (other than fluorescence or harmonic generation) is generally difficult to measure because it is overwhelmed by the large background of detected illumination light. Especially challenging to measure is the nonlinear refractive index – accessing this quantity would allow the extension of widely employed phase microscopy methods to the nonlinear regime. We have developed a technique to suppress the background in these types of measurements by using femtosecond pulse shaping to encode nonlinear interactions in background-free regions of the frequency spectrum. Using this individual pulse shaping based technique we have been able to measure self-phase modulation (SPM) in highly scattering environments, such as biological tissue, with very modest power levels. Using our measurement technique we have demonstrated strong intrinsic SPM signatures of glutamate-induced neuronal activity in hippocampal brain slices. We have also extended this measurement method to cross-phase modulation, the two-color analogue to SPM. The two-color approach dramatically improves the measurement sensitivity by reducing undesired background and associated noise. We will describe the nonlinear phase contrast measurement technique and report on its application for imaging neuronal activity.
Renewable fuels from biomass: Technical hurdles and economic assessment of biological routes

Lignocellulosic biomass is an abundant, renewable source of polysaccharides that could be available in amounts sufficient to provide a source of sugars for carbon neutral biofuel production. We review the background to biofuels production in the US from corn sugars and subsequent R and D efforts to saccharify plant biomass to provide an alternative sugar source. Research efforts and programs have generally not addressed the key technical hurdles in providing a commodity-scale supply of biomass and in developing biological routes to saccharify it at high yields. Techno-economic analyses of proposed processes highlight the importance of biomass cost, the role of pretreatment on both inhibitor generation, and the contribution of enzyme costs to saccharification. Alternatives, such as the production of fatty acids by microalgae, have comparable technical hurdles. Although there is a regulatory framework for biofuels, which is discussed, a credible biological process for large-scale, cost-effective production of lignocellulosic biofuels remains elusive.
Energy Variations in Optical Pulses from Gain-Switched AlGaAs Diode Lasers

One method for producing optical pulses as short as <20 ps FWHM with a diode laser is by gain switching. For such a laser, gain switching is readily achieved by applying an electrical (forward bias) pulse excitation to the diode. The average duration of the resulting optical pulses depends on the detailed shape of the electrical drive pulse and the dynamic response of the laser diode (in its package) to that drive pulse. Streak camera measurements1–2 have demonstrated that significant temporal substructure is present on the optical pulse, with subpulses of duration below 10 ps. This substructure changes dramatically from pulse to pulse. Previously reported work on gain switching of laser diodes has been almost exclusively confined to minimizing the time-averaged optical pulse duration, spectral width, and time- bandwidth product. An important additional consideration for ultrafast electro-optical sampling applications is the energy contained in the optical pulse, which should ideally be large and constant to minimize both shot noise and averaging time in the optical detection system. Little work has been done heretofore to quantify the variation in energy of diode laser optical pulses.3 We present here the results of a series of measurements of this energy variance in pulses produced by gain switching commercially available double heterostructure AlGaAs laser diodes.
Sources of HOx and production of ozone in the upper troposphere over the United States

The sources of HO x (OH+peroxy radicals) and the associated production of ozone at 8-12 km over the United States are examined by modeling observations of OH, HO 2 , NO, and other species during the SUCCESS aircraft campaign in April-May 1996. The HO x concentrations measured in SUCCESS are up to a factor of 3 higher than can be calculated from oxidation of water vapor and photolysis of acetone. The highest discrepancy was seen in the outflow of a convective storm. We show that convective injection of peroxides (CH 3 OOH and H 2 O 2 ) and formaldehyde (CH 2 O) from the boundary layer to the upper troposphere could resolve this discrepancy. More generally, the data collected over the central United States during SUCCESS suggest that local convection was a major source of HO x and NO x to the upper troposphere. The OH and HO 2 observations together with the observations of NO allow us to directly calculate the ozone production in the upper troposphere and its dependence on NO x . We find an average net ozone production of 2 ppbv day -1 between 8 and 12 km over the continental United States in the spring. Ozone production was NO x -limited under essentially all the conditions encountered in SUCCESS. The high levels of HO x present in the upper troposphere stimulate ozone production and increase the sensitivity of ozone to NO x emissions from aircraft and other sources.
Performance surfaces of the constant modulus algorithm based on a conditional Gaussian model

A stochastic analysis of the performance surfaces for four versions of the constant modulus algorithm is presented. By conditioning on the transmitted data symbols, the equalizer output is modeled as a Gaussian process, from which closed-form expressions of the performance functions are derived. The resulting conditional expectations are then evaluated according to the probability distribution of the conditioning symbols. This approach leads to analytical results that might otherwise be difficult to derive without the immediate conditioning step. >
A Comparison of Instructional Methods for Weight Loss in Women

This study tested effects of three methods for delivering a weight-loss education program for women. Seventy-four predominantly White participants at least 10 pounds over healthy weight began the program. Their average age was 41.7 years (range = 19 to 73), weight 173 pounds, Body Mass Index (BMI) 29.36, and waist/hip ratio .77. Participants were randomly placed into three groups: classroom (24), textbook (25), or computer program (25). The curriculum for all participants was taken from the same weight-loss manual, and all participants completed the same weekly assignments. Participants’ weight loss, BMI, and waist/hip ratios were compared at the end of the program. Weight loss (F = 29.4, p < .001; 2, 102 DF), reduction in BMI (F = 29.5, p < .001; 2, 102 DF]), and waist/hip ratio reduction (F = 3.11, p < .05; 2, 102 DF) across all groups were significant. There were no significant group differences in weight loss, BMI, waist/hip ratio reduction, or drop-out rates.
Efficient mRNA polyadenylation requires a ubiquitin-like domain, a zinc knuckle, and a RING finger domain, all contained in the Mpe1 protein.

Almost all eukaryotic mRNAs must be polyadenylated at their 3′ ends to function in protein synthesis. This modification occurs via a large nuclear complex that recognizes signal sequences surrounding a poly(A) site on mRNA precursor, cleaves at that site, and adds a poly(A) tail. While the composition of this complex is known, the functions of some subunits remain unclear. One of these is a multidomain protein called Mpe1 in the yeast Saccharomyces cerevisiae and RBBP6 in metazoans. The three conserved domains of Mpe1 are a ubiquitin-like (UBL) domain, a zinc knuckle, and a RING finger domain characteristic of some ubiquitin ligases. We show that mRNA 3′-end processing requires all three domains of Mpe1 and that more than one region of Mpe1 is involved in contact with the cleavage/polyadenylation factor in which Mpe1 resides. Surprisingly, both the zinc knuckle and the RING finger are needed for RNA-binding activity. Consistent with a role for Mpe1 in ubiquitination, mutation of Mpe1 decreases the association of ubiquitin with Pap1, the poly(A) polymerase, and suppressors of mpe1 mutants are linked to ubiquitin ligases. Furthermore, an inhibitor of ubiquitin-mediated interactions blocks cleavage, demonstrating for the first time a direct role for ubiquitination in mRNA 3′-end processing.
A Dominant-Negative fur Mutation in Bradyrhizobium japonicum

In many bacteria, the ferric uptake regulator (Fur) protein plays a central role in the regulation of iron uptake genes. Because iron figures prominently in the agriculturally important symbiosis between soybean and its nitrogen-fixing endosymbiont Bradyrhizobium japonicum, we wanted to assess the role of Fur in the interaction. We identified a fur mutant by selecting for manganese resistance. Manganese interacts with the Fur protein and represses iron uptake genes. In the presence of high levels of manganese, bacteria with a wild-type copy of the fur gene repress iron uptake systems and starve for iron, whereas fur mutants fail to repress iron uptake systems and survive. The B. japonicum fur mutant, as expected, fails to repress iron-regulated outer membrane proteins in the presence of iron. Unexpectedly, a wild-type copy of the fur gene cannot complement the fur mutant. Expression of the fur mutant allele in wild-type cells leads to a fur phenotype. Unlike a B. japonicum fur-null mutant, the strain carrying the dominant-negative fur mutation is unable to form functional, nitrogen-fixing nodules on soybean, mung bean, or cowpea, suggesting a role for a Fur-regulated protein or proteins in the symbiosis.
Effect of Solidification Time on the Microstructure and Physical Properties of Dental Gold Casting Alloys

SYNOPSIS IN INTERLINGUALE EFFECTO DEL TEMPORE DE SOLIDIFICATION SUPER LE MICROSTRUCTURA E LE PROPRIETATES PHYSIC DE ALLIGATOS FUSIONAL DE AURO DENTAL.-Esseva determinate: le longor del tempore requirite pro obtener solidification, le dimensiones del grano, le duritate de Vicker, le grado de porositate, e limite del elasticitate in flexion, e le modulo del elasticitate de specimens de alligato de auro dental fusionate a 5 differentes temperaturas. Le resultatos indica que fundition a alte temperatura prologa le solidification del alligato e resulta in un producto con plus grossier structura granular, plus basse duritate, e extense porositate, e plus basse limites de elasticitate que productos fusionate a plus basse temperaturas.
Total Pancreatectomy for Treatment of Pancreatic Adenocarcinoma

Successful total pancreatectomy was first performed in 1942 by Priestley at the Mayo Clinic in Rochester, Minnesota for an insulinoma ( 1 ). In 1944, Fallis at the Henry Ford Hospital in Detroit, Michigan undertook the first successful total pancreatectomy for pancreatic carcinoma ( 2 ). Soon, recommendations were made from several centers for total pancreatectomy in anticipation to cure pancreatic cancer (3 ). In the early 1970s, total pancreatectomy was advocated by several groups as the preferred resection for pancreatic adenocarcinoma. The reasoning for this decision was several-fold. Most surgeons were dissatisfied by survival outcomes after pancreatoduodenectomy and were looking for reasons that might explain the inordinately high recurrence rate ( 4 ). The option of total pancreatectomy was based on the belief that pancreatic adenocarcinoma was multicentric with undetected foci of neoplasm within the remnant gland (up to 30%) which would be addressed by complete excision. The operation provided a generous pancreatic parenchymal margin with a potentially better oncologic resection (lymphadenectomy and soft tissue clearance), all of which were felt to be advantageous for survival. The absence of need for a pancreaticoenterostomy and its associated morbidity was welcomed by elimination of pancreatic fistulae which at the time were associated with high mortality. The inevitable loss of endocrine and exocrine pancreatic function and the associated splenectomy with its infectious sequelae, although taken into consideration, may not have been appreciated fully. In the mid-1980s, it became evident that total pancreatectomy did not provide a superior outcome compared to other forms of pancreatic resections, and the true incidence of multicentricity has been shown to be quite low ( 5 , 6 ). Currently, the concept of total pancreatectomy as a routine procedure in the management of pancreatic adenocarcinoma is rejected, and only a selected approach is still in use.
Social contexts of momentary craving to smoke among Korean American emerging adults

Abstract Introduction Korean American emerging adult (KAEA) smokers represent a culturally and developmentally unique population constituted of primarily light, intermittent smokers. Sociocultural contexts might play an important role in contributing to instances of acute cigarette craving and motivation to smoke in this population; yet, research testing such hypotheses is scant. The current study tests whether and how social contexts are associated with the craving among KAEA smokers. Methods Seventy-eight daily KAEA smokers, who smoke 4 + cigs/day, participated in a 7-day ecological momentary assessment (EMA), in which participants responded to both signal-contingent (random) and event-contingent (smoking) prompts to answer surveys on their mobile phones (prompt-level n = 1377; 603 random + 774 smoking prompts). Nicotine dependence was measured at baseline; cigarette craving, negative affect, presence of others smoking, social contexts were measured with EMA. Results Modeling of within-participant variation and covariation showed that being with Korean friends (vs. alone) was associated with increased levels of momentary craving. This association between Korean friends and craving disappeared when adjusted for presence of others smoking, which was a strong predictor of momentary craving. The positive association between Korean friends and craving was amplified immediately prior to smoking (vs. non-smoking random) instances. Conclusions Being with Korean friends might serve as a culturally-specific salient smoking cue, which might have been learned throughout their smoking history. Our data also showed that increased craving associated with Korean friends may represent social settings that primarily involve cigarette smoking. Given our findings on cigarette use among KAEA's social network, addressing cigarette use as a group behavior might be a fruitful intervention strategy.
Electrochemical dioxygen reduction catalyzed by a (nitro)cobalt(perfluorophthalocyanine) complex and the possibility of a peroxynitro complex intermediate

The (nitro)(N,N′-dimethyl-4-aminopyridine) complex of perfluorinated cobalt(III) phthalocyanine Co(III)F16Pc(Me2Npy)(NO2) catalyzes the electrochemical oxygen reduction reaction (ORR) in pH 4.0, 7.0, and 10.0 buffer and 0.05 M sulfuric acid solution when deposited on a glassy carbon electrode. Cyclic voltammetry (CV), rotating disk electrode voltammetry (RDE), and rotating ring-disk electrode voltammetry (RRDE) have been used to determine the reduction product as hydrogen peroxide although in concentrations too small to observe by qualitative methods such as oxidation of NaI in solution. The dependence of the values of the peak potentials for the reduction on the pH of the solution and the -log[Me2Npy] are consistent with protonation up to pH 7.6 and pyridine ligand loss during the reduction. The addition of nitrite at 0.1 and 1 M to pH 7.0 solutions in contact with films of CoF16Pc on the glassy carbon electrode decreases the ORR current and shifts the peak potential of the ORR from -0.21 V vs. NHE to -0.19 V vs. NHE. The addition of nitrite at 0.1 and 1 M to films of Co(III)F16Pc(Me2Npy)(NO2) on glassy carbon, however, has no effect on either the current or the potential. While the electrochemical evidence for this proposal is not definitive, modeling has been used to examine the center of reduction in the alternative mechanisms by evaluation of the LUMOs of the hypothetical intermediates in both closed and open shell cases. The formation of five-coordinate Co(II)F16Pc(NO) is proposed to occur initially in the reduction mechanism. It is also possible that O2 reduction takes place at the NO ligand center by way of a nitrogen-bound peroxynitrite intermediate. The NO/NO2- ligand appears to remain bound during the ORR. Direct coordination of O2 to the metal center requiring a six-coordinate species, Co(III)F16Pc(O2)(NO2), Co(II)F16Pc(O2)(NO) or [Co(II)F16Pc(O2)(NO2)]- and has been considered in DFT modeling studies. The instability of the two-electron reduced, protonation species, [Co(I)F16Pc(NO2OH)]- in its loss of peroxynitrous acid suggests that the reduction of O2 may occur by two one-electron reduction steps rather than a two-electron step.
Tunable and Energetically Robust PbS Nanoplatelets for Optoelectronic Applications

PbS nanoplatelets (NPLs) are proposed as robust materials for novel optoelectronic devices. Compared to quantum dot assemblies, ab initio simulations are employed to show that such pseudo-two-dimensional systems may provide stronger absorption and higher carrier mobility due to the distinct wave function distributions, large electronic couplings, and small hopping barriers. More importantly, both energetic and spatial traps are absent in conditions far from charge balance, indicating an extraordinary robustness against off-stoichiometry as a result of surface homogeneity and sufficient cross-linking. Based on our findings, we present several types of optoelectronic device architectures spanning photovoltaics and photodetectors that could take advantage of the superior properties found in NPLs.
Models of mechanics

General Background.- Open scheme.- Basic Models: Geometry and Universal Laws.- Bodies and Their Placements in ?.- Discrete Model.- One-Dimensional Model.- Pipe Flow.- Three-Dimensional Model.- Complete Models by Adding Particular Laws.- Particular Laws.- Small Displacement Models.- Pipe Flow Models.- Models of Fluid Mechanics.- Kinematic Constraints, Beams and Rigid Bodies.