cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of catalase amplification on immortal lens epithelial cell lines.

Abstract Utilizing a human β-actin promoter, a catalase cDNA expression vector was constructed. This construct was used to transfect two immortal cell lines, mouse αTN4-1 and rabbit N/N 1003A. The catalase activity was increased about 3.4 fold in the αTN4-1 cells and 38 fold in the N/N 1003A cells. Some changes in other enzyme activities were also observed as a result of the transfections. Surprisingly, the ability to degrade H2O2in the extracellular environment of the cells did not markedly change as a result of the catalase amplification. However, the ability to resist H2O2stress was dramatically altered. Non-protein thiol (NP-SH) levels, choline uptake and glyceraldehyde phosphate dehydrogenase (GPD) activity were all markedly decreased in the non-transfected cells when they were subjected to 300 μ m H2O2. However, in both transfected cell lines, these parameters remained in the normal range during H2O2stress. The results obtained upon observing aspects of DNA metabolism were more complicated. While on H2O2stress, non-transfected cell lines showed a marked decrease in thymidine incorporation, only the transfected αTN4-1 line remained in the normal range. Thymidine incorporation in transfected rabbit N/N 1003A cells was decreased compared to normal cells. In contrast, studies on single strand DNA breaks indicated that transfected rabbit cells had little damage compared to the significant DNA damage observed in the normal cells. The normal N/N 1003A cells were also much more susceptible to H2O2induced damage than normal αTN4-1 cells, suggesting that the high GSH peroxidase activity observed in the rabbit cells may be detrimental since the low glutathione reductase activity in such cells results in an accelerated depletion of glutathione. The overall results suggest that augmenting lens catalase may prevent cataract development caused by H2O2stress.
Capacity fade study of lithium-ion batteries cycled at high discharge rates

Abstract Capacity fade of Sony US 18650 Li-ion batteries cycled using different discharge rates was studied at ambient temperature. The capacity losses were estimated after 300 cycles at 2C and 3C discharge rates and were found to be 13.2 and 16.9% of the initial capacity, respectively. At 1C discharge rate the capacity lost was only 9.5%. The cell cycled at high discharge rate (3C) showed the largest internal resistance increase of 27.7% relative to the resistance of the fresh cells. The rate capability losses were proportional with the increase of discharge rates. Half-cell study and material and charge balances were used to quantify the capacity fade due to the losses of primary active material (Li+), the secondary active material (LiCoO2/C)) and rate capability losses. It was found that carbon with 10.6% capacity loss after 300 cycles dominates the capacity fade of the whole cell at high discharge rates (3C). A mechanism is proposed which explains the capacity fade at high discharge rates.
Behavioral characterization: Finding and using the influential factors in software process simulation models

Abstract Most software process simulation work has focused on the roles and uses of software process simulators, on the scope of models, and on simulation approaches. Consequently, the literature reflects a growing body of models that have recently been characterized by modeling purpose, scope, key result variables, and simulation method. While the software process simulation arena is maturing, little effort appears to have been given to statistical evaluation of model behavior through sensitivity analysis. Rather, most of software process simulation experimentation has examined selected factors for the sake of understanding their effects with regard to particular issues, such as the economics of quality assurance or the impact of inspections practice. In a broad sense, sensitivity analysis assesses the effect of each input on model outputs. Here, we discuss its use for behaviorally characterizing software process simulators. This paper discusses the benefits of using sensitivity analysis to characterize model behavior; the use of experimental design for this purpose; our procedure for using designed experiments to analyze deterministic simulation models; the application of this procedure to four published software process simulators; the results of our analysis; and the merits of this approach.
The Color Paradigm: The Impact of Colorism on the Racial Identity and Identification of Latinas

Existing research has provided scant analysis on the impact of colorism or skin color privilege and stigma on racial identity and identification among Latinos/as. This article explores the dynamics of colorism and the impact on racial identity and identification among Latinos/as of varying phenotypes. The experiences of a subset of eight Caribbean Latinas and one Chicana are used to illustrate how Latinas negotiate their racial identification and survive experiences of both stigma and privilege within the U.S. context. The article concludes with implications for social work research, practice, and pedagogy.
Biased diffusion and pairing of impurities in quantum crystals

Abstract We calculated the time of pairing of ortho -H 2 impurities in solid para -H 2 . The quantum diffusion has a strong directional bias which at moderate temperatures is against a mutual approach of particles and creates a “kinetic barrier”. At lower temperatures, this barrier freezes out causing a rapid increase in pairing rates. This explains a well-developed maximum in the pairing time as a function of temperature.
Nitrogen and phosphorus fertilization of Sparganium eurycarpum Engelm. and Typha glauca Godr. stands. II: Emergent plant decomposition

Biweekly elevation of available nitrogen and phosphorus concentrations in marsh surface waters did not alter the rate of Sparganium eurycarpum Engelm. or Typha glauca Godr. shoot decomposition. After 505 days, losses of shoot material totaled 39% for both species under fertilized and unfertilized conditions. However, Sparganium shoot litter with an initial nitrogen concentration of 1.41% lost 27% more dry weight over a 505-day period than did Sparganium with an initial concentration of 0.59%. Typha shoot litter with an initial concentration of 0.55% lost 2% more dry weight during 505 days than Typha tissues with an initial nitrogen concentration of 0.48%. During the 505-day sampling interval, quantities of nitrogen in shoot litter increased 31% for Sparganium and decreased 10% for Typha under unfertilized conditions. Unfertilized Sparganium shoot litter lost 2% and unfertilized Typha litter gained 25% of original phosphorus quantities. Under fertilized conditions, nitrogen quantities increased 35% for the 2 species. The quantity of phosphorus in Sparganium and Typha shoot litter increased 7 and 121%, respectively, with fertilization. Sparganium shoot litter with a high initial nitrogen concentration lost 50% of its original quantity of nitrogen over 505 days, but high-nitrogen Typha shoot litter gained an additional 19% nitrogen.
Activin A and transforming growth factor-β stimulate heart formation in axolotls but do not rescue cardiac lethal mutants

In the Mexican axolotl (salamander), Ambystoma mexicanum, a recessive cardiac lethal mutation causes an incomplete differentiation of the myocardium. Mutant hearts lack organized sarcomeric myofibrils and do not contract throughout their lengths. We have previously shown that RNA purified from normal anterior endoderm or from juvenile heart tissue is able to rescue mutant embryonic hearts in an in vitro organ culture system. Under these conditions as many as 55% of formerly quiescent mutant hearts initiate regular contractions within 48 hours. After earlier reports that transforming growth factor-β1 and, to a lesser extent, platelet-derived growth factor-BB could substitute for anterior endoderm as a promoter of cardiac mesodermal differentiation in normal axolotl embryos, we decided to examine the effect of growth factors in the cardiac mutant axolotl system. In one type of experiment, stage 35 mutant hearts were incubated in activin A, transforming growth factors-β1 or β2, platelet-derived growth factor, or epidermal growth factor, but no rescue of mutant hearts was achieved. Considering the possibility that growth factors would only be effective at earlier stages of development, we tested transforming growth factors-β1 and β5, and activin A on normal and mutant precardiac mesoderm explanted in the absence of endoderm at neurula stage 14. We found that, although these growth factors stimulated heart tube formation in both normal and mutant mesodermal explants, only normal explants contained contractile myocardial tissue. We hypothesize that transforming growth factor-β superfamily peptides initiate a cascade of responses in mesoderm that result in both changes in cell shape (the basis for heart morphogenesis) and terminal myocardial cytodifferentiation. The cardiac lethal mutation appears to be deficient only in the latter process.
A new species of Rhytachne (Poaceae: Andropogoneae) from northern South America

Rhytachne gonzalezii is described and illustrated. It ranges from Apure, Venezuela to Para, Brazil. It is the third annual species known in this tropical African-American genus. Previously it had been confounded with the perennialR. rottboellioides from which it differs in its habit, branching culms, smaller sessile spikelets and rachis internodes, and awned upper glume.
Kindergarten Teachers' Perspectives on Developmentally Appropriate Practices (DAP): A Study Conducted in Mumbai (India)

A qualitative study examining teachers' beliefs regarding developmentally appropriate practices was conducted in the city of Mumbai, India. Twelve kindergarten teachers were interviewed for this study, and a constant comparative method was used to analyze the interviews. Six themes were identified within this study. The themes highlighted distinct differences between American and Indian cultures, as well as striking similarities, and pinpoint the importance of culture as the foundation for classroom practices. Themes included a focus on academics vs. play, the importance of worksheets, the importance of groups for socialization, and the difficulties of implementing a play-based curriculum. The description of these themes and its implication for the early childhood care and education of India are discussed in detail.
The spatial model with non-policy factors: a theory of policy-motivated candidates

The theoretical literature on two candidate elections is dominated by symmetric contests and vote-maximizing candidates. These models fail to capture two important features of real elections. First, most elections pit a stronger candidate against a weaker one. Second, candidates care not only about holding office, but also about policy outcomes. Ignoring any one of these features means we will fail to capture an important dynamic—strong candidates must balance their desire to change policy with their need to win the election. We provide conditions for the existence of an equilibrium in the spatial model with non-policy factors, when candidates are policy motivated. We provide a characterization of ‘regular’ equilibria and show that there exists at most one regular equilibrium. We provide conditions that guarantee that all equilibria are regular. We derive comparative statics for the model and show that increasing a candidate’s non-policy advantage causes that candidate to move towards his ideal point.
The value of adding design-for-the-environment to pollution prevention assistance options

Abstract The design stage of product development, recognized as key for determining costs and profitability, is also an unparalleled window of opportunity to champion the environment. During this early stage key materials, process, and energy source decisions determine the environmental impacts of a product for its entire life cycle. Integration of environmental factors into design is an emerging trend known as design-for-the-environment (DfE), ecodesign, or life-cycle design. From this perspective, designers gain inherent drivers for optimizing design and efficient use of resources. The intent of this article is to inspire expansion of pollution prevention assistance portfolio options to include DfE.
Human chorionic gonadotropin: Amino acid sequence of the α and β subunits

Summary The linear amino acid sequences of the α and β subunits of human chorionic gonadotropin have been determined. HCG-α has 92 and HCG-β 139 amino acid residues. There is more homology between HCG-α and ovine LH-α than between HCG-β and ovine LH-β.
"Days of the week" effect in predicting the time taken to fix defects

In this paper, we investigate the effect of calendar on the activity of fixing defects in a project, i.e., whether the days of the week when defects are reported have an impact on the time taken to fix them. Interestingly, we show that there is an effect, and that this can be used to predict the time taken to fix defects.
Long-term results of a second endoscopic third ventriculostomy in children: retrospective analysis of 40 cases.

OBJECTIVE: To evaluate retrospectively the operative findings and long-term results of a repeat endoscopic third ventriculostomy (ETV) in pediatric hydrocephalic patients readmitted after the first procedure with symptoms and/or signs of intracranial hypertension and/or radiological evidence of increased ventricular dilation and/or occluded stoma on follow-up radiological examinations. METHODS: We analyzed a series of 482 ETVs in pediatric patients from 2 Italian departments of pediatric neurosurgery. The clinical charts of 40 patients undergoing a second ETV were selected and reviewed retrospectively. The pre- and postoperative radiological findings and operative films were analyzed retrospectively. RESULTS: Forty patients underwent a total of 82 ETVs. Thirty-eight patients were operated on twice and 2 were operated on 3 times. During the second procedure, the stoma was found to be closed in 28 patients without underlying adhesions, to be open but with significant arachnoid adhesions in the prepontine cistern in 8 patients, to be open without adhesions in 2 patients, to have a pinhole orifice in 1 patient, and to be closed with underlying adhesions in 1 patient. The second procedure allowed reopening of the stoma or lysis of the arachnoid adhesions in 35 patients and was abandoned in 3 patients because of extensive arachnoid adhesions or because the stoma was found to be wide open (2 patients). In 30 patients (75%), the second ETV was effective, and the 2 patients who underwent a third ETV remained shunt free. In 10 patients (25%), a ventriculoperitoneal shunt was eventually placed. Age younger than 2 years at the time of the first procedure and arachnoid adhesions in the subarachnoid cisterns observed during the second procedure are the main negative prognostic factors for the success of a second ETV. CONCLUSION: A second ETV can be performed with a reasonable chance of restoring patency of the stoma and avoiding placement of an extrathecal shunt. Every effort should be made to detect subarachnoid adhesions in the cistern on preoperative imaging study to select potential candidates and avoid unnecessary procedures.
A hemA mutation renders Salmonella typhimurium avirulent in mice, yet capable of eliciting protection against intravenous infection with S. typhimurium.

Abstract The hemAmutation reduces the virulence of Salmonella typhimurium for mice by at least 107-fold, as measured by change in LD50. The hemAmutation does not appear to affect killing of salmonella in mice. The salmonella with the hemAmutation persist in the spleen and liver for 2 to 3 weeks following intravenous injection. The most likely effect of the hemA mutation is to block, or retard, growth of S. typhimurium in an aerobic in vivo environment. Intravenous vaccination of susceptible Itys mice with hemA salmonella was able to elicit about 4 logs of protection against invasive infection with wild-type S. typhimurium 78 days after vaccination, at a time when the vaccine strain was no longer detectable in the spleen and liver.
MPEG Video transcoding with joint temporal-spatial rate control

Novel temporal-spatial rate control solutions for MPEG video transcoding are investigated in this paper. We present two rate control approaches for MPEG video transcoding, one for IPP (including only I and P frames, no B frames) streams and the other for IBP (including I, P and B frames) streams. The proposed rate control schemes adapt the frame rate and the quantization step size simultaneously according to the available channel bandwidth to achieve a good temporal-spatial quality tradeoff. In our proposed solutions, key frames are not allowed for skipping in order to maintain the prediction sequential order, and the MPEG-4 quadratic Rate-Qtz model is adopted to calculate the quantization step size from a given target bit rate. Simulations show that the proposed rate control method for IPP stream transcoding achieves a higher average PSNR value than the MPEG-4 rate control (frame level) with a constant frame rate in CBR channels. Furthermore, the proposed rate control method for IBP stream transcoding can significantly enhance the transcoded video quality in VBR channels, in comparison with straightforward MPEG video transcoding by adjusting the quantization step size at a constant frame rate. The two proposed transcoders are in low computational complexity so that they can be used in real-time transcoding applications.
Osmoregulation, solute distribution, and growth in soybean seedlings having low water potentials.

Soybean (Glycine max (L.) Merr.) seedlings osmoregulate when the supply of water is limited around the roots. The osmoregulation involves solute accumulation (osmotic adjustment) by the elongating region of the hypocotyls. We investigated the relationship between growth, solute accumulation, and the partitioning of solutes during osmoregulation. Darkgrown seedlings were transplanted to vermiculite containing 1/8 (0.13 x) the water of the controls. Within 12–15 h, the osmotic potential of the elongating region had decreased to-12 bar, but it was-7 bar in the controls. This osmoregulation involved a true solute accumulation by the hypocotyls, since cell volume and turgor were virtually the same regardless of the water regime. The hypocotyls having low water potentials elongated slowly but, when deprived of their cotyledons, did not elongate or accumulate solute. This result indicated a cotyledonary origin for the solutes and a dependence of slow growth on osmotic adjustment. The translocation of nonrespired dry matter from the cotyledons to the seedling axis was unaffected by the availability of water, but partitioning was altered. In the first 12 h, dry matter accumulated in the elongating region of the 0.13 x hypocotyls, and osmotic adjustment occurred. The solutes involved were mostly free amino acids, glucose, fructose, and sucrose, and these accounted for most of the increased dry weight. After osmotic adjustment was complete, dry matter ceased to accumulate in the hypocotyls and bypassed them to accumulate in the roots, which grew faster than the control roots. The proliferation of the roots resulted in an increased root/shoot ratio, a common response of plants to dry conditions.
The power and practice of Virginia county boards

Due to city-coounty separation, county government is a rural job in Virginia. But it hasn't been too successful, and Governor Trinkle has recommended the county manager plan. Another article in our series on county government.
Revealed preferences for car tax cuts: an empirical study of perceived fiscal incidence

Voting in an election in which elimination of the local car tax is the central issue shows how a highly visible universal tax cut can prevail in the electoral process even if benefits are skewed toward upper income households. These results are consistent with positive models of fiscal structure choice in which fiscal systems are the consequence of support maximizing politicians attempting to supply net benefits to easily identifiable interest groups without generating significant opposition from other groups.
Principal components of the surface wind field in the United States: a comparison of analyses based upon wind velocity, direction, and speed

Three statistical summaries of the 1975 surface wind field in the United States are computed using principal components analysis (PCA). Separate analyses of wind velocity and direction are made with vector-based PCA, and the scalar (zonal and meridional) components of wind are described using a scalar-based PCA. Comparisons indicate that results of the three PCAs are not equivalent. Vector PCA yields the most physically comprehensive components because the velocity observations are not decomposed into direction and speed, or into zonal and meridional coordinates a priori. Directional and scalar-based PCAs appear similar but since they only summarize one coordinate of velocity at a time, they represent incomplete descriptions of the wind field. Vector-based PCA then is the most appropriate of the three for investigating wind fields or other vector-valued data sets.
A novel form of mastocytosis associated with a transmembrane c-kit mutation and response to imatinib

Mutational analysis of the c-kit gene in a patient with a previously undescribed variant of mast cell disease revealed a germline mutation, Phe522Cys, within the transmembrane portion of the Kit receptor protein. Transfection experiments revealed that the mutation caused ligand-independent autophosphorylation of Kit, which was inhibited by the tyrosine kinase inhibitor imatinib mesylate. The patient's bone marrow biopsy and aspirate displayed unique pathologic features with the presence of excessive numbers of mature-appearing mast cells and absence of aberrant mast cell surface expression of CD2, CD25, and CD35. Therapy with imatinib mesylate resulted in a dramatic improvement in mast cell burden and clinical symptoms. These results highlight the significance of the transmembrane region of Kit in activation of the molecule and its importance in mast cell development and suggest a role for screening for transmembrane c-kit mutations in patients with mastocytosis in association with the decision to use imatinib mesylate.
Glucose-dependent respiration in suspensions of rabbit cortical tubules

The effects of glucose on cellular respiration were examined in suspensions of rabbit cortical tubules. When glucose was removed from the bathing fluid, oxygen consumption (QO2) decreased from 18.6±0.8 to 15.7±0.5 nmol O2/mg protein·min (P<0.01). The transported but nonmetabolized analogue of glucose, α-methyl-d-glucoside (αMG), was found to support QO2 to the same extent as glucose. These observations were also evident in the presence of butyrate, a readily oxidized substrate of the renal cortex. Additional studies with nystatin and ouabain indicated that glucose-related changes in QO2 were the result of changes in Na, K-ATPase associated respiration. The effect of glucose was localized to the luminal membrane since phlorizin (10−5 m), a specific inhibitor of liminalk glucose-sodium cotransport, also significantly reduced QO2 by 10±1%. Phlorizin inhibition of QO2 was also evident in the presence of αMG but was abolished when glucose was removed from the bathing medium. Finally, measurement of NADH fluorescence showed that addition of glucose (5mm) to a tubule suspension causes an oxidation of NAD. These data are all consistent with glucose acting to increase respiration by stimulating sodium entry at the luminal membrane (via glucose-sodium cotransport) followed by increased sodium pump activity and its associated increase in mitochondrial respiration.
IS EVERYTHING ALL RIGHT IF NOTHING SEEMS WRONG? A SIMPLE METHOD OF ASSESSING THE DIAGNOSTIC VALUE OF ENDOSCOPIC PROCEDURES WHEN A GOLD STANDARD IS ABSENT

AbstractPurpose: We demonstrate a simple yet comprehensive method to evaluate the sensitivity of endoscopic procedures when no gold standard is available.Materials and Methods: In 208 consecutive patients with superficial bladder cancer 328 endoscopies were performed to compare the sensitivity of white light and 5-aminolevulinic acid induced fluorescence endoscopy. Both procedures were performed during the same session.Results: The maximum interval of observable sensitivity for 5-aminolevulinic acid induced fluorescence endoscopy ranged between 78 and 97.5%, and the best estimate for sensitivity based on realistic assumptions was 93.4% (95% confidence intervals 90 to 97.3). The best sensitivity estimate for white light endoscopy was 46.7% (95% confidence intervals 39.4 to 54.3, maximum range 47.2 to 53%).Conclusions: This method to determine the maximum possible range of sensitivity estimates for endoscopic procedures without a gold standard is easily applied. Depending on the assumptions a range of reaso...
Anorexic activity of cocaine and coca extract in naive and cocaine tolerant rats

Abstract Dose response curves for reducing limited access food consumption were determined for cocaine HC1 IP, cocaine HC1 PO, and whole Erythroxylum coca extract PO. The ED 50 's for cocaine HC1 in drug naive rats were 19.6 mg/kg (IP) and 34.6 mg/kg (PO). When the dose of E . coca extract was expressed in terms of cocaine HC1 content, the ED 50 was 52.6 mg/kg (PO). When dose response curves were determined in rats that had received cocaine (45 mg/kg, PO) for 30 days, a shift to the right in the cocaine HC1 curve (an ED 50 of 98.4 mg/kg PO) indicated tolerance. However, the shift to the right was less for E . coca extract than for cocaine HCI. Although the anorexic activity of E . coca extract was less than that of an equivalent amount of cocaine in naive rats it was often more than that of equivalent doses of cocaine HC1 in tolerant rats. Interaction with other constituents of E . coca extract appears to alter the potency of the cocaine content of the extract in different directions in naive and tolerant rats.
Overexpression of Ogt reduces MNU and ENU induced transition, but not transversion, mutations in E. coli.

Abstract Studies of alkylation-induced mutations in Escherichia coli FX-11 revealed that both N -ethyl- N -nitrosourea (ENU) and N -methyl- N -nitrosourea (MNU) produced tRNA suppressor mutations (G:C to A:T) but only ENU produced a significant number of backmutations (A:T to G:C, A:T to T:A and A:T to C:G). Further, the ENU-induced transversions were absent in a UmuC-defective strain. This suggested that transition mutations could result from alkylation of guanine or thymine at the O 6 - and O 4 -positions, respectively, but that transversions might result from alkylation of thymine at the O 2 -position. To test this idea, the gene encoding O 6 -alkylguanine-DNA methyltransferase ( ogt ) was recombined into a plasmid to overexpress the cellular levels of this enzyme. Ogt protein can de-alkylate O 6 -alkylguanine and O 4 -alkylthymine, but not O 2 -alkylthymine. Cells harboring the plasmid (or a control plasmid lacking the ogt gene) were exposed to different concentrations of MNU or ENU and the resulting mutations were analyzed. With either MNU or ENU, the frequency of GlnV o suppressors was reduced about 70-fold in the Ogt-overexpressing cells, suggesting that Ogt eliminated O 6 -alkylguanine. Similarly, GlnU o suppressor frequencies were substantially reduced. In contrast, the reduction in frequency for the backmutations was slight, only about 2.5-fold with MNU and less than two-fold for ENU. However, DNA sequence analysis of the backmutations showed that only A:T to G:C transitions were affected by overexpression of Ogt, suggesting repair of O 4 -alkylthymine. The frequency of transversions, in comparison, was essentially unaltered. These results implicate O 2 -alkylthymine as a likely candidate for transversion mutagenesis induced by ENU.
Low Temperature Growth of Oriented Gallium Nitride using Pulsed Laser Deposition

Oriented GaN has been successfully grown at low substrate temperatures (∼480°C) on a- and r-planes of sapphire, using the pulsed laser deposition process. We have examined the effects of several deposition parameters on film growth, including substrate temperature (∼50–500°C), ambient pressure (1×10−3 – 10 torr of NH3), and target material (Ga or GaN). The film deposition rate was typically ∼3–4 μm/hr. Film characterization was performed using x-ray diffraction (XRD), optical microscopy, x-ray photoelectron spectrometry (XPS), and atomic force microscopy (AFM). In the case of the Ga metal target, a plasma (∼500V) between the target and substrate was necessary to promote formation of the GaN phase. The ammonia ambient enhanced the nitrogen content in the films compared to vacuum deposition. In general, the GaN target yielded better quality films (smaller rocking curve widths and smoother film morphology) compared to the Ga metal target. These results suggest that pulsed laser deposition is a promising approach to fabricating high quality films of this potentially important semiconducting material.
Implementing Team-Based Learning in Middle School Social Studies Classes

ABSTRACTThe authors examined the effects of team-based learning (TBL) implemented in Grade 8 social studies classes on student content acquisition. Twenty-four classes were randomly assigned to treatment or comparison blocking on teacher. In the treatment classes teachers integrated TBL practices in the content instruction. The authors examined teacher instruction in the treatment and comparison classes during implementation. Results indicated TBL was implemented only in treatment classes and teachers demonstrated a novice level of implementation. The authors then examined the effects of the treatment implementation on measures of content acquisition. Significant differences in favor of the treatment condition were noted in the number of accurate content ideas produced in a written essay (effect size = .31). A small effect (.16) was also observed in the number of supporting details students provided in the essay but was not statistically significant. There was no benefit of the treatment on a multiple-cho...
High-Throughput Thermal Scanning: A General, Rapid Dye-Binding Thermal Shift Screen for Protein Engineering

The low stability of natural proteins often limits their use in therapeutic, industrial, and research applications. The scale and throughput of methods such as circular dichroism, fluorescence spectroscopy, and calorimetry severely limit the number of variants that can be examined. Here we demonstrate a high-throughput thermal scanning (HTTS) method for determining the approximate stabilities of protein variants at high throughput and low cost. The method is based on binding to a hydrophobic dye akin to ANS, which fluoresces upon binding to molten globules and thermal denaturation intermediates. No inherent properties of the protein, such as enzymatic activity or presence of an intrinsic fluorophore, are required. Very small sample sizes are analyzed using a real-time PCR machine, enabling the use of high-throughput purification. We show that the apparent TM values obtained from HTTS are approximately linearly related to those from CD thermal denaturation for a series of four-helix bundle hydrophobic core...
Hope and Worry in Mothers of Children with an Autism Spectrum Disorder or Down Syndrome.

Abstract Mothers of children with an autism spectrum disorder (n = 199) or Down syndrome (n = 60) responded to an online questionnaire that assessed their hope and worry. Findings support previous research suggesting that hope is a protective factor against psychological distress: mothers with higher hope reported lower worry. Mothers who reported lower worry had more education and older children or children who were higher functioning. Those whose children had Down syndrome reported lower future-related worry and higher hope. In response to an open-ended question regarding what they worried about when they woke up at night, mothers’ responses resulted in themes related to themselves as well as to their children and families.
Team project patterns for college students

Team Project Patterns for College Students is a pattern language intended for use by faculty instructing college students. The language is not designed for the college or university environment where courses are taught online but rather can be applied universally to third level education. There are two goals with implementing these patterns: (i) Team Building and (ii) Enhance Shared Learning. In writing these patterns, we were using examples of semester-long projects.
Microbial utilization of dissolved organic matter from leaves of the red mangrove, Rhizophora mangle, in the Fresh Creek estuary, Bahamas

Abstract Dissolved organic matter was leached from [ 14 C]labeled leaves of the red mangrove, Rhizophora mangle , and used in studies to determine the rates and efficiencies of microbial utilization of the water-soluble components of mangrove leaves in the Fresh Creek estuary, Bahamas. Rates of microbial utilization (assimilation plus mineralization) of mangrove leachate ranged from 0·022 to 4·675 μg ml −1 h −1 depending on the concentration of leachate and the size or diversity of microbial populations. Microflora associated with decaying mangrove leaves utilized mangrove leachate at rates up to 18-fold higher than rates of leachate utilization by planktonic microflora. Chemical analyses indicated that tannins and other potentially inhibitory phenolic compounds made up a major fraction (18%) of the dissolved organic matter in mangrove leachate. Mangrove leachate did not appear to be inhibitory to the microbial uptake of leachate or the microbial degradation of the lignocellulosic component of mangrove leaves except at high concentrations (mg ml −1 ). The availability of molecular oxygen also was an important parameter affecting rates of leachate utilization; rates of microbial utilization of leachate were up to 8-fold higher under aerobic rather than anaerobic conditions. The overall efficiency of conversion of mangrove leachate into microbial biomass was high and ranged from 64% to 94%. As much as 42% of the added leachate was utilized during 2 to 12 h incubations, indicating that a major fraction of the leachable material from mangrove leaves is incorporated into microbial biomass, and thus available to animals in the estuarine food web.
Waterspout Velocity Measurements by Airborne Doppler Lidar

Abstract A Doppler lidar measures the line-of-sight velocity of cloud droplets in a waterspout much as a meteorological Doppler radar measures the velocity of larger hydrometeors. We discuss details of the application of an airborne Doppler lidar to waterspout velocity measurements, including intensity weighting and limitations of the technique. One type of result available from the lidar data is the velocity spectrum of the line-of-sight velocity component of scatterers in the flow, integrated along the lidar axis, as a function of distance from the vortex axis. From the velocity spectra, peak winds in the portion of the waterspout marked by cloud droplets, turbulence levels, and interaction with the ambient flow can be inferred. In one example the maximum velocity observed in the visible part of the waterspout is 10 m s−1. This double-walled waterspout showed a two-peaked velocity spectrum, which we interpret as a dynamic difference between the two coaxial components of the vortex.
Exploring the flexibility of ribosome recycling factor using molecular dynamics.

Ribosome recycling factor is proposed to be flexible, and that flexibility is believed to be important to its function. Here we use molecular dynamics to test the flexibility of Escherichia coli RRF (ecRRF) with and without decanoic acid bound to a hydrophobic pocket between domains 1 and 2, and Thermus thermophilus RRF (ttRRF) with and without a mutation in the hinge between domains 1 and 2. Our simulations show that the structure of ecRRF rapidly goes from having an interdomain angle of 124° to an angle of 98° independently of the presence of decanoic acid. The simulations also show that the presence or absence of decanoic acid leads to changes in ecRRF flexibility. Simulations of wild-type and mutant ttRRF (R32G) show that mutating Arg-32 to glycine decreases RRF flexibility. This was unexpected because the range of dihedral angles for arginine is limited relative to glycine. Furthermore, the interdomain angle of wild-type T. thermophilus goes from 81° to 118° whereas the R32G mutant remains very close to the crystallographic angle of 78°. We propose that this difference accounts for the fact that mutant ttRRF complements an RRF deficient strain of E. coli whereas wild-type ttRRF does not. When the ensemble of RRF structures is modeled into the ribosomal crystal structure, a series of overlaps is found that corresponds with regions where conformational changes have been found in the cryoelectron microscopic structure of the RRF/ribosome complex, and in the crystal structure of a cocomplex of RRF with the 50S subunit. There are also overlaps with the P-site, suggesting that RRF flexibility plays a role in removing the deacylated P-site tRNA during termination of translation.
The effect of 2-deoxyglucose on guinea pig polymorphonuclear leukocyte phagocytosis†

The effects of 2-deoxyglucose (DOG), an inhibitor of glycolysis, on guinea pig polymorphonuclear leukocytes (PMN) obtained from peritoneal exudates was examined. ATP levels in PMN were reduced by 40% by one hour following an incubation with 2-deoxyglucose. When complement (C3) coated 14C-staphylococcus aureus, C3 coated lipopolysaccharide-paraffin oil droplets (LPS-PO), 14C-pneumococcus opsonized with IgG, or albumin coated paraffin oil droplets opsonized with IgG were added to cell suspensions containing DOG, the phagocytizing rate was 1,310+/-55 cpm/5 X 10(6) cells/15 minutes, 6+/-2 microng paraffin oil (PO)/10(7) cells/minute, 2,250+/-175 cpm/1 X 10(6) cells/20 minutes or 0.037+/-0.01 mg PO/10(7) cells/minute compared to control values of 5,970+/-275 cpm/5 X 10(6) cells/15 minutes, 35+/-3 microng PO/10(7) cells/15 minutes, 4,510+/-200 cpm/1 X 10(6) cells/20 minutes and 0.067+/-0.01 mg PO/10(7) cells/minute. In parallel studies the phagocytic index for latex was 0.74+/-0.28 in DOG compared to control of 2.36+/-1.13 and the phagocytic rate of albumin coated paraffin oil droplets was 0.029+/-0.01 mg PO/10(7) PMN/minute in DOG compared to control of 0.048 mg PO/10(7) cells/minute. When ATP levels were maintained by the simultaneous addition of 5 mM glucose or pyruvate to media containing DOG, latex ingestion was improved to 1.15+/-0.3 with glucose and 1.59+/-0.64 with pyruvate and albumin coated particles to 0.045+/-0.01 mg PO/10(7) PMN/minute with pyruvate. There was no improvement in the uptake of either the C3 dependent particles or IgG coated Pneumococci in media containing DOG and glucose and/or pyruvate. Following the removal of DOG from the extracellular medium and the addition of pyruvate or glucose, phagocytosis of C3 dependent LPS-PO was restored to normal values. Neither the binding of C3 or IgG coated particles to the PMN nor the lateral movement of glycoprotein utilizing concanavalin A capping was affected by DOG. Thus, the presence of DOG in the PMN containing adequate amounts of ATP will selectively and reversibly inhibit those surface events required for phagocytosis of C3 and IgG bound particles but not latex particles or albumin particles which non-specifically bind to PMN.
Low-cycle fatigue of titanium 6A1-4V surgical tools

Abstract A handle holder is used in heart valve replacement surgery to insert a mechnical flow valve into the patient's heart. In order to position the valve correctly, a 0.1″ diameter titanium 6Al4V handle holder shaft is bent until the proper angle is found. This bending of the tool makes it vulnerable to low-cycle fatigue failure. Low cycle fatigue testing of titanium 6A1-4V specimens shows that surface cracks appear approximately 20 cycles before failure occurs. It is recommended that the tool be carefully inspected before each used and replaced when surface cracks appear. The data showed that the life of the tool may be increased by 30% if it is bent in the same direction during its entire use.
The Protective Influence of Family Bonding on Smoking Initiation in Adolescents by Racial/Ethnic and Age Subgroups

Using data from the National Longitudinal Study of Adolescent Health, this study examined the associations among family bonding factors and the initiation of smoking by race/ethnicity and age group among nonsmokers at Wave 1. Overall, 18% of the sample initiated smoking by Wave 2. For younger African American and Hispanic youth, high maternal satisfaction with the relationship was significantly protective of smoking initiation. For older Hispanics, high parental presence and high parent-family connectedness were protective against smoking initiation while lack of awareness about the adolescent's whereabouts was a risk factor for initiation in both younger and older Caucasians, and in the older Hispanics. Our results underscore the importance of maintaining high levels of family bonding with the adolescent throughout early and late adolescence in order to decrease tobacco initiation.
Humic acids as reducing agents: the involvement of quinoid moieties in arsenate reduction

Purpose Dissolved humic acids abiotically reduced inorganic arsenic to varying degrees, depending on solution pH, ionic strength, and type of humate used. The functionalities of dissolved organic matter responsible for these redox reactions remained in question, but quinoid moieties undoubtedly played an important role. It is not fully understood whether the quinoids are solely responsible for arsenate reduction, and what the kinetics of the relevant processes are.
Biogeography of woody encroachment: why is mesquite excluded from shallow soils?

While some studies aim to generalise the attributes of woody encroachers, examining their functional differences across biogeographic regions may also be instructive. Most of Texas is encroached by Prosopis glandulosa, but on the eastern Edwards Plateau, a limestone plateau with thin soils, P. glandulosa is rare and Juniperus ashei is dominant. We hypothesised that P. glandulosa is excluded from sites where bedrock at a depth of 1 m or less restricts the development of taproots, thus rendering this normally deep-rooted species too vulnerable to drought. To test this idea, we monitored the physiological status of the two species on a site where both species were encroaching and the soil was 1·5-2·5 m deep, thus relatively deep for the Edwards Plateau region but not for regions where P. glandulosa dominates. Data were collected across three tree size classes from May to November 2006. Stem water potentials were similar across species and water potentials and photosynthetic rates decreased with tree size. Based on isotopic evidence, the effective rooting depth of P. glandulosa increased with tree size, but not in J. ashei. P. glandulosa had a higher rate of leaf gas exchange overall as expected for a drought-avoider; except for large trees during a summer drought, when species differences in photosynthesis rates diminished and the stomatal conductance for J.ashei exceeded that of P. glandulosa. We speculate that restrictions of soil depth may limit the invasiveness of P. glandulosa in part through negative effects on large trees, which may lower fecundity.
The Nuclear Matrix Protein CDP Represses Hepatic Transcription of the Human Cholesterol-7α Hydroxylase Gene *

To date, the molecular mechanisms that govern hepatic-specific transcription of the human cholesterol 7α-hydroxylase (CYP7A1) gene are poorly understood. We recently reported that the region extending from −1888 to +46, which includes the promoter, is not capable of conferring expression to human CYP7A1 promoter lacZ transgenes in the livers of mice, but that expression is observed with transgenes containing the entire structural gene. To locate liver-specific elements in other segments of the human gene, DNase I hypersensitivity studies were performed with transcriptionally active, liver-derived HepG2 cells and with transcriptionally inactive HeLa cells. Three DNase I hypersensitivity sites were detected within the first intron of the humanCYP7A1 gene, but only in HepG2 cells. Transient transfection experiments with HepG2 cells revealed a transcriptional repressor within intron 1. Five binding sites for the CAAT displacement protein (CDP) were detected within intron 1. Since CDP is a nuclear matrix protein, two methods were employed to localize nuclear matrix attachment sites within intron 1 of the human CYP7A1 gene. A matrix attachment site was found throughout the entirety of intron 1. Gel retardation experiments and cell transfection studies provided evidence for the repression mechanism. Repression is achieved by displacement by CDP of two hepatic activators, namely HNF-1α and C/EBPα, that bind to three different sites within intron 1. Additionally, CDP represses transactivation mediated by these two activators.
Crystallographic characterization of flavodoxin from Anacystis nidulans.

Flavodoxin isolated from the blue-green alga, Anacystis nidulans, crystallizes from ammonium sulfate in space group P212121, with a = 57.08 A, b = 69.24 A and c = 45.55 A. The diffraction patterns extend to a resolution of at least 1.8 A. Reduction of the flavin mononucleotide in the crystalline protein, to either the semi-quinone or fully reduced (hydroquinone) state, results in minimal changes in cell dimensions and diffracted intensities. The higher molecular weight (19,000 to 20,000) and spectral properties of the A. nidulans protein, along with the near-isomorphism of crystals of the three oxidation states, distinguish this crystalline flavodoxin from the corresponding proteins of Clostaridium MP and Desulfovibrio vulgaris, whose three-dimensional structures are known. In contrast to Clostridium flavodoxins, but like the D. vulgaris protein, A. nidulans flavodoxin is capable of binding riboflavin in place of flavin mononucleotide (Ka = 2 × 106m−1).
Mobility Identification of a Group of Single Degree-of-Freedom Eight-Bar Linkages

This paper presents the first complete and automated mobility identification method for a group of single-DOF planar eight-bar linkages and thus represents a breakthrough on the recognition and understanding of complex linkage mobility. The mobility identification in this paper refers to the configuration space, the range of motion, and configuration recognition. It is a troublesome problem encountered in any linkage analysis and synthesis. The problem becomes extremely confusing with complex multiloop linkages. The proposed approach is simple and straightforward. It recognizes that the loop equations are the mathematical fundamentals for the formation of branches, sub-branches, and other mobility issues of the entire linkage. The mobility information is then extracted through the discriminant method. The paper presents complete answers to all typical mobility issues, offers the mathematical insight as well as explanation on the effects of multiple loops via joint rotation space, and casts light for treating the mobility problems of other complex linkages. The merits of the discriminant method for mobility identification are clarified and examples are employed to showcase the proposed method. The computer-aided automated mobility analysis of eight-bar linkages is made possible for the first time.Copyright © 2010 by ASME
Microdosimetry and the Effects of Small Doses of Radiation

Microdosimetry provides detailed information on stochastic fluctuations of energy deposition in irradiated tissues. On the basis of these physical data one may draw basic conclusions regarding the biological action of radiations, particularly in the case of small values of the absorbed dose.
Insularity, Sovereignty and Statehood: The Representation of Islands on Portolan Charts and The Construction of The Territorial State

This article investigates the cartographic origins of the idea that the territorial state is a unified, bounded, homogeneous and naturally occurring entity, in a world of equivalent but unique enti...