cssi/SciSciGPT-SciSciNet huggingface dataset:
Math5 encodes a murine basic helix-loop-helix transcription factor expressed during early stages of retinal neurogenesis

We have identified Math5, a mouse basic helix-loop-helix (bHLH) gene that is closely related to Drosophila atonal and Xenopus Xath5 and is largely restricted to the developing eye. Math5 retinal expression precedes differentiation of the first neurons and persists within progenitor cells until after birth. To position Math5 in a hierarchy of retinal development, we compared Math5 and Hes1 expression in wild-type and Pax6-deficient (Sey) embryos. Math5 expression is downregulated in Sey/+ eyes and abolished in Sey/Sey eye rudiments, whereas the bHLH gene Hes1 is upregulated in a similar dose-dependent manner. These results link Pax6 to the process of retinal neurogenesis and provide the first molecular correlate for the dosage-sensitivity of the Pax6 phenotype. During retinogenesis, Math5 is expressed significantly before NeuroD, Ngn2 or Mash1. To test whether these bHLH genes influence the fates of distinct classes of retinal neurons, we ectopically expressed Math5 and Mash1 in Xenopus retinal progenitors. Unexpectedly, lipofection of either mouse gene into the frog retina caused an increase in differentiated bipolar cells. Directed expression of Math5, but not Xath5, in Xenopus blastomeres produced an expanded retinal phenotype. We propose that Math5 acts as a proneural gene, but has properties different from its most closely related vertebrate family member, Xath5.
A stepped waveguide technique for the characterization of conductor-backed absorbing materials

A variety of techniques have been developed for measuring the electromagnetic properties of homogeneous, isotropic materials. Commonly, a sample is excised and placed into a waveguide cross section, and the S-parameters of the system are measured. The well-known Nicolson-Ross-Weir technique is then used to find both the permeability and permittivity of the material in closed form. Certain conditions, however, prevent this approach from being used. Many radar absorbing materials are manufactured with a conductor backing that cannot be removed without potentially altering their electromagnetic properties. The materials are typically quite thin, and cannot be easily increased in thickness. Because of the conductor backing, they cannot be used to fill a waveguide cross section since no transmission would be available. Similarly, since their thickness cannot be increased, a two-thickness reflection technique cannot be employed.
The “Pituitary Ring Sign”: An MRI Sign of Pituitary Apoplexy

Purpose: To describe a magnetic resonance imaging (MRI) sign of pituitary apoplexy. Methods: The cranial MRI scans of 3 patients with pituitary apoplexy were retrospectively reviewed. Results: All 3 patients displayed a distinctive MRI sign of an enlarged pituitary gland with peripheral gadolinium enhancement surrounding a hypointense gland. Conclusions: The “pituitary ring sign” can aid in the early diagnosis and treatment of pituitary apoplexy.
Cerebrovascular disease in an elderly population.

A sample of residents of a retirement community was investigated for symptoms and signs thought to be premonitory of stroke, as the initial step in a study of factors that predict the occurrence of stroke. Persons who had experienced a prior stroke reported a number of symptoms more frequently than did persons who had not had a stroke. The stroke group had a higher prevalence of cervical bruits, higher mean blood pressures, and significantly more abnormal electrocardiograms. There were no differences for cholesterol or hemoglobin.
Mantle Convection and Plate Tectonics: Toward an Integrated Physical and Chemical Theory

Plate tectonics and convection of the solid, rocky mantle are responsible for transporting heat out of Earth. However, the physics of plate tectonics is poorly understood; other planets do not exhibit it. Recent seismic evidence for convection and mixing throughout the mantle seems at odds with the chemical composition of erupted magmas requiring the presence of several chemically distinct reservoirs within the mantle. There has been rapid progress on these two problems, with the emergence of the first self-consistent models of plate tectonics and mantle convection, along with new geochemical models that may be consistent with seismic and dynamical constraints on mantle structure.
Effects of race and clinical factors on short-term outcomes of abdominal myomectomy.

Abstract Objective To estimate the effects of race and preoperative uterine anatomy on complication rates after myomectomy. Methods A total of 239 abdominal myomectomies were performed at Duke University Medical Center from July 1992 through June 1998. Charts were abstracted using standardized forms. We assessed patient characteristics, surgical indications, preoperative hematocrit, and operative findings. Outcomes were defined as any complication, including transfusion. Results The population (n = 225) was 53% black and 47% white. The mean body mass index was 26. Fourteen percent had comorbidities. Twenty percent required transfusion. Black women were found to be more likely to have uteri with more than four leiomyomata and less likely to have only one leiomyoma (P = .001). Black women were 2.48 times more likely to have a complication (P Conclusion Black women undergoing myomectomy are more than twice as likely to have in-hospital complication or blood transfusion than white women. This is largely attributable to differences in uterine size and leiomyoma number. Research is needed to explore why black women are more likely to have larger and more numerous leiomyomata at the time of presentation for surgery.
Resistance to Cold in Ceratomia catalpae

SALT1 has reported resistance to frost and to being frozen in several species of arthropods. He has also reported on the synthesis and accumulation of a low molecular weight solute (glycerol) in insects and has suggested that this may explain resistance to cold2. Lozina-Lozinsky3 stated that in the caterpillar, Pyrausta nubilalis, which can tolerate extremely low temperatures, the proteins and nucleoproteins can resist an increase in concentrations of the electrolytes. Asahina and Tanno4 found that the overwintering pre-pupal larvae of a sawfly, Trichiocampus populi, were able to survive freezing at −30° C for a full day, and withstand liquid nitrogen temperature (−195.8° C) provided they had been previously frozen at temperatures lower than −20° C.
Warehousing the Elderly

NATION IS UNDERGOING A DEMOGRAPHIC REVOLUTION. The huge baby boom generation is approaching retirement, with a life expectancy higher than that of previous generations. It had few children, and birth rates remain at bare replacement levels. The resulting rise in the ratio of the elderly to the rest of the population is already a problem in terms of the cost of pensions and health care. The future decline in the ratio of workers to retirees will make these
Development of the self‐supporting polymer tooth implant

The central theme of our studies is concerned with finding a better means of tooth replacement. This goal is being realized for a “tailor-made” polymer and associated techniques of usage have been developed for this purpose. In the course of doing this, we have introduced the polymer implant concept by which materials can be tailor made to serve different functions. The polymer composition currently considered best for these studies contains clear polymethacrylate powder and liquid monomer, blowing agent (dinitrosopentamethylene tetramine), anorganic bone, and N-tributyl phosphate. This mixture is heat processed in a plaster mold at 300° F for 30 min. The processed implant is sandblasted to remove its outer skin and to open the pores on the implant's surface to the host's tissues when implanted. This formulary has resulted in the totally self-supporting replica implant becoming a reality in baboons. Two Papio-Anubis baboons', both with 8 incisors (4 upper and 4 lower) were replaced with polymer replicas, and after 3 months the splints were severed and the 16 implants remained totally self-supporting. Metals have been coated with this polymer formula, and polymer coated pins have been used successfully as supports for fixed prostheses and as endodontic stabilizers. The internal metal piece imparts increased strength without bulk, while the polymer coating allows for attachment to the implant. The untoward effects of metals, such as heat transfer, electrical and corrosive phenomena are diminished or eliminated. This “happy union” of the two materials allows the implant to be strong and well integrated into the host. The Polymer Implant Concept holds a genuine hope for the future. In this instance it provides for a better means of tooth replacement: one which is cosmetically and functionally excellent. Most probably it will have an important place in the neurosurgical, orthopedic, and medical fields as well.
Rat pup isolation distress and the brain benzodiaze pine receptor

Pharmacologic studies have demonstrated that benzodiazepines can modulate the ultrasonic vocalizations (USV) associated with social separation of rat pups. In this study, in vivo receptor autoradiography was used to determine if brain benzodiazepine receptors were functionally less available to bind an exogenous ligand during social separation. The labeled benzodiazepine receptor antagonist, 3H-RO 15-1788, was given to 10-day-old rat pups with varying schedules of social separation. In initial studies with homogenized and solubilized tissue, we found a 30% reduction in binding to cortex when pups were separated for 25 min beginning 5 min prior to tracer injection. In subsequent autoradiographic studies with this same separation schedule, the binding of 3H-RO 15-1788 was examined in 21 brain regions. Again binding was decreased in neocortex (frontal, motor, and somatosensory). In addition, we found significantly decreased binding in hippocampus, dentate gyrus, and superior and inferior colliculi. These same regions showed no alteration of in vitro binding of 3H-RO 15-1788. Therefore, these decreases in in vivo binding do not reflect changes in receptor number. The interpretation of decreased in vivo binding and implications of these results for defining the neural substrates of separation behavior are discussed.
Sensitivity of complex, internally coupled systems

A method is presented for computing sensitivity derivatives with respect to independent (input) variables for complex, internally coupled systems, while avoiding the cost and inaccuracy of finite differencing performed on the entire system analysis. The method entails two alternative algorithms: the first is based on the classical implicit function theorem formulated on residuals of governing equations, and the second develops the system sensitivity equations in a new form using the partial (local) sensitivity derivatives of the output with respect to the input of each part of the system. A few application examples are presented to illustrate the discussion.
Divalent americium: The crystal structure and magnetic susceptibility of AmI2

Abstract The preparation and identification of divalent americium, as AmI2, are reported. Lattice constants for the monoclinic AmI2 are a 0 = 7·677 ± 0·003 A , b = 8·31 ± 0·004 A , c = 7·925 ± 0·003 A and β = 98·46±0·03°. The effective magnetic moment for AmI2 is μeff = 6·7±0·7 BM. AmOI was also prepared, and the lattice constants for the tetragonal cell are a 0 = 4·011±0·002 A and c = 9·204±0·007 A .
Oxygen isotopic composition of the Luna 20 soil.

Comparison of the oxygen isotopic composition in the Luna 20 soil sample with the oxygen isotopic abundances of the Apollo 11, 12, 14, and 15 lunar soil samples. The Luna 20 soil is found to have a relatively low delta 0-18 content (0.57%) in comparison to the other lunar soils (0.58 to 0.63%).
Teaching and Learning about Inquiry: Insights and Challenges in Professional Development.

The purpose of this study was to determine if teachers who participated in a professional development program continued to learn about inquiry and inquiry teaching as they implemented inquiry in their classrooms. A qualitative design utilizing inductive analysis was used to investigate teachers’ understanding and classroom implementation of inquiry. Findings are presented as assertions, drawing support from four focal teachers. For each assertion, confirming and disconfirming data are presented. Based on these data, we assert that a) there was little or no change in teachers’ individual understanding of inquiry, and b) professional development enhanced teachers’ ability to design inquiry-based activities – however, classroom implementation did not reflect a high level of inquiry.
Glycoconjugates as noninvasive probes of intrahepatic metabolism: II. Application to measurement of plasma α 1-acid glycoprotein turnover during inflammation

We describe a new method for measuring plasma glycoprotein turnover in vivo using carbohydrate-moiety labeling compared with precursor UDP-sugar monitoring, which allows estimation of the specific activity of the precursor at the biosynthetic site of the glycoprotein. This method has been applied to plasma alpha 1-acid glycoprotein (AGP) kinetics, and has allowed direct quantitation of absolute synthesis rates of AGP in a non-steady state. Following turpentine-induced acute inflammation, AGP was found to undergo a maximum increase in plasma level of eight-fold with a 20- to 25-fold induction in absolute synthesis rate peaking at 25 to 50 h, and a concurrent 2.0 to 2.5-fold increase in fractional degradation rate. The changes in absolute synthesis rates were quite comparable both temporally and quantitatively to changes in hepatic AGP mRNA levels and gene transcription rates reported by others following turpentine inflammation, thus suggesting that AGP synthesis in vivo is predominantly regulated by the level of its mRNA. The carbohydrate moiety labeling method can be applied to other plasma glycoproteins to measure their kinetic parameters in the intact animal or human subject.
SEQUENCE OF EXTREME BELIEF‐INCONGRUENT VERSUS NEUTRAL INFORMATION IN SOCIAL PERCEPTION1

Order of presenting neutral versus highly belief-discrepant (magical child-care or deviant sexual practices) information on evaluations of a stimulus person was studied in 570 college students. As hypothesized, neutral preceding belief-discrepant content created much greater rejection than did the reverses sequence. When the vivid sexual and child-care messages were themselves paired, order of presentation had negligible immediate effect upon social perception. The recency effects for neutral plus deviant messages were generally maintained after four weeks delay, but an unanticipated primacy effect was found when both deviant (child-care and sex) messages were presented. Information aimed at fostering cultural relativism reduced delayed rejection to a significant but numerically small extent. The data suggested that stimulus vividness affects social perception, and that future research needs to explicate the relative contributions of vividness and valence to impression formation.
Bursa and ganglion

Abstract Thirty-seven cases of bursitis have been encountered over a period of six years. These cases were susceptible of classification on an etiologic basis into acute and chronic types, each of which was further subdivided. Forty-one bursae were removed surgically and to our knowledge, only eight of these have recurred since operation. Eight known different diseases affected the forty-one bursae which were removed and trauma was the most common cause of chronic bursitis in this group of cases. Complete excision is the procedure of choice in the treatment of chronic bursitis that is associated with persistent swelling and disability. Chronic subdeltoid bursitis should be treated conservatively, unless such measures have proved to be ineffective. One hundred two cases of ganglion have been encountered over a period of six years. These cases represented 104 ganglions, in the treatment of which 115 surgical procedures were used. The ratio of males to females was 1:3. Of these 102 cases, permanent results of treatment have been determined in seventy-one. From all methods of treatment, good results occurred in 59 per cent of cases. Of the various treatments employed, complete surgical excision of the sac offered the best results.
The Research on Certainty-Based Secure Routing Protocol in Wireless Sensor Networks

Secure routing protocol is one of research focuses in wireless sensor networks. The paper presents a secure routing protocol named CBSRP, which creates dynamic keys based on certainty. The protocol is implemented on MICAz suite. The performance of CBSRP is compared with those of other secure routing protocols through experiments finally
The timing of 52-week high price and momentum

Abstract We propose a new momentum strategy based on the timing of a stock’s 52-week high price. We find that the stocks that attained the 52-week high price in the recent past significantly outperform the stocks that attained the 52-week high price in the distant past. In particular, the top 10% of the stocks with the most recent 52-week high price outperform the bottom 10% of the stocks with most distant 52-week high price by 0.70% per month. Further, conditioning on the recency of 52-week high price significantly increases the profitability of momentum strategy based on the nearness of current price to the 52-week high price. Specifically, the average monthly return of this strategy is about twice as large for stocks with recent 52-week high price as compared with stocks with distant 52-week high price.
Charge accumulation and mobility in thin dielectric MOS transistors

Abstract A study of the turn-on of very thin dielectric MOS devices from subthreshold to strong inversion is described. A functional form has been found for the derivative of channel charge with respect to gate voltage, the derivative of channel charge with respect to distance along the channel, and the electric field along the channel in this transition region. A method to extract electron mobility versus gate voltage independent of any arbitrarily defined threshold voltage has been shown. Measured data on the electron mobility vs gate voltage for 100A gate dielectric MOS devices are reported.
Optical rotation at the free surface of a nematic liquid crystal

Abstract When a small droplet of a nematic liquid crystal is placed on a horizontal glass plate in the presence of a magnetic field, the plane of polarization of light transmitted upward through the liquid crystal can be rotated. A defect usually forms preferring a direction perpendicular to the magnetic field and forming a diagonal of the droplet. This defect divides the free surface into regions giving rise to optical rotations that are clockwise and counterclockwise. It is suggested that the defect may be similar to a Helfrich splay-bend wall and the optical rotation in the regions near the defect may be explained by surface effects at the free surface of a liquid crystal.
Coarse-graining the electrostatic potential via distributed multipole expansions

Multipole expansions offer a natural path to coarse-graining the electrostatic potential. However, the validity of the expansion is restricted to regions outside a spherical enclosure of the distribution of charge and, therefore, not suitable for most applications that demand accurate representation at arbitrary positions around the molecule. We propose and demonstrate a distributed multipole expansion approach that resolves this limitation. We also provide a practical algorithm for the computational implementation of this approach. The method allows the partitioning of the charge distribution into subsystems so that the multipole expansion of each component of the partition, and therefore of their superposition, is valid outside an enclosing surface of the molecule of arbitrary shape. The complexity of the resulting coarse-grained model of electrostatic potential is dictated by the area of the molecular surface and therefore, for a typical three-dimensional molecule, it scale as N2/3 with N, the number of charges in the system. This makes the method especially useful for coarse-grained studies of biological systems consisting of many large macromolecules provided that the configuration of the individual molecules can be approximated as fixed.
Calcium is essential for the major pseudopilin in the type 2 secretion system

The pseudopilus is a key feature of the type 2 secretion system (T2SS) and is made up of multiple pseudopilins that are similar in fold to the type 4 pilins. However, pilins have disulfide bridges, whereas the major pseudopilins of T2SS do not. A key question is therefore how the pseudopilins, and in particular, the most abundant major pseudopilin, GspG, obtain sufficient stability to perform their function. Crystal structures of Vibrio cholerae, Vibrio vulnificus, and enterohemorrhagic Escherichia coli (EHEC) GspG were elucidated, and all show a calcium ion bound at the same site. Conservation of the calcium ligands fully supports the suggestion that calcium ion binding by the major pseudopilin is essential for the T2SS. Functional studies of GspG with mutated calcium ion-coordinating ligands were performed to investigate this hypothesis and show that in vivo protease secretion by the T2SS is severely impaired. Taking all evidence together, this allows the conclusion that, in complete contrast to the situation in the type 4 pili system homologs, in the T2SS, the major protein component of the central pseudopilus is dependent on calcium ions for activity.
Innovations in Teaching Styles and Approaches Based upon Adult Learning

(1972). Innovations in Teaching Styles and Approaches Based upon Adult Learning. Journal of Education for Social Work: Vol. 8, No. 2, pp. 32-39.
Element Mobility in Bald Cypress Xylem

Trace element mobility in bald cypress (Taxodium distichum) was investigated for a suite of elements using cores from century-old trees from a wetland in Humphreys County, Mississippi. Element mobility was determined by comparing the dendrochemistry of decadal increments over the life span of a tree, and by comparing increments of the same age collected from the same tree during two different seasons. Variability within growth increments at the time of sampling was evaluated by comparing cores from the same tree collected at three points around the bole. Of 42 elements analyzed, eight were found above detection limits (As, Ca, K, Mg, Mn, Na, P, Zn). Clear evidence of translocation of P and Mn to the sapwood and K, Mg, and Na to the heartwood was observed. Ca and Zn were found with higher average concentrations in the sapwood, though evidence of translocation to the sapwood was equivocal. Arsenic did not vary significantly through any individual core. Variation in concentration was not found to be signific...
Complex envelope correlations for non-isotropic scattering

The author describes the correlational properties of the complex envelope of a non-isotropically scattered mobile radio signal specified by Clarke's model. The scattering probability density function of the arriving waves is chosen to describe directional propagation that would occur in an urban environment.
Analysis of US renewable fuels policies using a modified MARKAL model.

Abstract In this research we have modified the standard US MARKAL model to include a land resource base, corn stover and miscanthus feedstocks, and new cost information for biochemical and thermochemical conversion technologies. We then used this revised MARKAL model to estimate the impacts of four different policy and technology choice scenarios; 1) no government interventions in biofuel markets (no RFS or subsidies), 2) biofuels RFS targets are implemented, 3) no government intervention but technology that combines coal and biomass feedstocks is enabled, and 4) biofuels RFS targets are implemented and combined coal-biomass feedstocks are enabled. Some of the major conclusions are as follows: • By 2030, with no government intervention, corn ethanol reaches about 15 bil. gal.(57 bil. liters), and thermochemical biofuel reaches 13 bil. gal.(49 bil. liters) for a combined 28 bil. gal.(106 bil. liters) by 2030. • When the RFS is added to the reference case, there is a substantial increase in both corn ethanol and thermochemical biofuel (about 6 bil. gal.(23 bil. liters) total) in the early years when the RFS is binding. • When combined coal-biomass technology is enabled for the reference (market) case, there is a huge increase in thermochemical biofuel after 2020. • When the RFS is added to the case with combined coal-biomass technology, the main impact is in the early years when the RFS is binding. • The average cost of the binding RFS compared with the reference case is 33 ¢/gal.(9 ¢/liter) in 2015 and 12 to 14 ¢/gal. after that. For the coal-biomass cases, the cost is 24 ¢/gal.(6 ¢/liter) in 2015 and zero after that. • Corn stover is generally less expensive, and it is used exclusively in the early years. As production ratchets up substantially in 2025 or 2030, more dedicated energy crops are used. We have demonstrated that the standard MARKAL results can be considerably enhanced by combining richer information on the land supply data from GTAP into MARKAL. Indeed, without use of this land supply data, MARKAL and other energy models cannot reliably be used for biofuels economic and policy analysis.
A flicker perception metric

A metric is proposed for predicting the perception of light source flicker from a measurement of the relative light output waveform. The metric is the weighted quadrature sum of the temporal spectral components comprising the waveform after dividing by the waveform mean. The metric’s foundation is that used by the IEC flickermeter, which assumes a linear, time invariant human response to flicker. This assumption, restated in terms of the spectral components being additive and independent, was found to accurately model the flicker detection thresholds for a range of waveform shapes and frequencies. In the testing of the additive and independence requirements, the empirical spectral sensitivity to flicker was measured for 10 observers. The metric also correctly predicted whether flicker was detected for five commercial A-lamps.
Off-Season Spawning of Yellow Perch

Abstract The thermal and light conditions for 2-year-old broodstock of yellow perch Perca flavescens were shifted by 6 months in an effort to change spawning from spring to autumn and fall. The natural photothermal conditions consisted of a chill period of 10°C and 10 h of light during January–March followed by increases in temperature to 20–22°C and photoperiod to 15 h light during July–September. The natural spawning of yellow perch occurs in April–May at 12–14°C and 12 h light. In the present study, the broodstock were maintained at a higher temperature and a longer period of light during September–February (18°C and 13 h light). The photothermal conditions were decreased gradually until June. The chill period (10°C and 11 h light) was 60 d in duration (June–July) and was followed by gradually increased water temperature and longer daylight (12°C and 19 h). Following this period, 50% of the females were fully ovulated, and they were stripped or spawned naturally. The males spermiated during the entire ...
The concept of intelligence and its role in lifelong learning and success.

I I This article proposes a definition of intelligence as com- prising the mental abilities necessary for adaptation to, as well as selection and shaping of any environmental context. According to this definition, although the behav- ior that is labeled as intelligent may differ from 1 envi- ronmental context to another, the mental processes un- derlying this behavior do not. An individual's ability to apply these processes may differ from 1 context to an- other, however. The abilities are applied to achieve exter- nal correspondence to the world and internal coherence among various knowledge and belief structures. The rele- vance of the definition for understanding current theo- ries, testing in the field of intelligence, as well as for understanding the role of inteUigence in lifelong learning is discussed.
The achromatic channel—I. The non-linearity of minimum-border and flicker matches

Abstract Flicker and minimum-border matches made at one intensity do not hold at other intensities. For flicker matches, more saturated lights must be increased relative to less saturated lights as intensity increases, in agreement with the hypothesis that a compression precedes the addition of the signals from the receptors. Minimum-border matches are more nearly linear. The two methods give the same radiances for an equal-luminance spectrum for a 100 troland standard; the methods depart for lower and higher intensities.
Housing Loan Patterns toward Minority Borrowers in Mississippi: Analysis of Some Micro Data Evidence of Redlining:

We apply a cross-regional probit analysis to examine the existence or otherwise of the discriminatory practice of “redlining” in housing loan lending practices of banks in Mississippi. Data on loan denial rates across three Mississippi regions of Tri-County Metro-Jackson, Southern Mississippi Corridor, and the Northern district are studied to determine the pattern of bank lending activities regarding owner-occupied housing loan extensions to minority members of Mississippi's population. The purpose is to determine the degree to which the banks have or have not observed fair and equitable lending practices toward minority borrowers, relative to the members of the majority population. The results suggest that there is a consistently high denial rates against minorities. The results indicate strong evidence of redlining practices in housing loan decisions, which contribute to the growth of racial segregation in the state.
What We're In For: Projected Economic Impact of the Next Recession

How bad could recession get? These two economists use the last three recessions to come up with the range of possibilities. Here is what could happen.
Some remarks on certain trivalent accounts of presupposition projection

This paper discusses some formal properties of trivalent approaches to presupposition projection, and in particular of the middle Kleene system of Peters (1977) and Krahmer (1998). After exploring the relationship between trivalent truth-functional accounts and dynamic accounts in the tradition of Heim (1983), I show how the middle Kleene trivalent account can be formulated in a way which shows that it meets the explanatory challenge of Schlenker (2006, 2008a,b), and provide some results relating to the application of the middle Kleene approach to generalised quantifiers.
Relay Loop Stabilizes the Force-Generating Region in Myosin

We have used transient time-resolved FRET (TR2FRET) to monitor the conformation of the relay helix in a myosin II functional mutant during the recovery stroke in real time. Myosin was perturbed with the F506A mutation (Dictyostelium discoideum sequence), located within the relay loop in the force-generating region. F506 is a highly conserved residue in myosin II and is a hypertrophic cardiomyopathy mutation site. Previous studies [Tsiavaliaris, EMBO Rep, 2002, 3(11), 1099] showed a significant effect of the F506A mutation on myosin function. Actin affinity in the presence of ATP was increased, and the mutant did not move actin filaments in in vitro motility assays. A small decrease in intrinsic fluorescence was observed upon addition of excess ATP, but ATP binding and hydrolysis were not affected by the mutation. It was proposed that the F506A disrupts the communication between the active site and the lever arm. We engineered a double-Cys myosin mutant (A639C:K498C) in the Cys-less background with the F506A functional mutation, and labeled the mutant with optical probes. We used TR-FRET to determine the interprobe distance, and TR2FRET measurements after rapid mixing with ATP revealed changes in the relay helix conformation during the recovery stroke in real time. The mutation induced significant disorder of the relay helix in the force-generating region, but myosin still produces a recovery stroke, changing the relay helix conformation from straight to bent. We conclude that (a) the relay helix is disordered in myosin functional mutant F506A, which demonstrates the importance of the relay loop - relay helix interaction in the relay helix stabilization, and (b) the relay helix is the major structural element in the force-generating region of myosin, responsible for communication from the active site to the converter domain and the lever arm.
The Moisture Dependence of the Electrical Sheet Resistance of Aluminum Oxide Thin Films with Application to Integrated Moisture Sensors

The measurement of moisture inside integrated circuit packages for reliability purposes involves either destructive mass spectroscopic tests, measurement of the impedance between interdigitated electrode pairs, or measurement of the capacitance of a parallel plate capacitor with a porous upper electrode and a dielectric of anodized aluminum oxide. This paper reports the use of an integrated circuit that combines interdigitated electrodes with a pair of matched field-effect transistors to permit sensitive, quantitative measurement of the moisture dependence of the sheet resistance of very thin filmis of oxidized aluminum. Data analysis is based on an equivalent circuit model for the device. It is found that the room temlperature sheet resistance of a 1500 A film varies from 2 × 1015 Ohms/sq. at an ambient dew point of ?43°C to 2 × 1010 Ohms/sq. at a dew point of +22°C. The device retains useful sensitivity below dew points of ?60°C, and because of the absence of a porous upper electrode, exh ibits rapid response to changes in ambient moisture. Fabrication details, reproducibility, hysteresis, and aging of these devices is discussed.
Solubility and diffusivity of solvents by packed column inverse gas chromatography

Abstract Inverse gas chromatography was used with solid polymer particles in packed columns to measure polymer–solvent solubility and diffusion. A new model for this IGC technique has been developed and used to obtain experimental results for n -pentane, isopentane, 1-hexene, n -hexane, and 1-octene solvents in polymer beads of polyethylene. The conditions were measured for solvents at infinite dilution, and experimental data were obtained for the binary polymer–solvent systems in a temperature range from 70 to 100 °C.
Approximate solutions to boundary value problems of higher order by the modified decomposition method

Abstract In this paper, we present an efficient numerical algorithm for approximate solutions of higher-order boundary value problems with two-point boundary conditions. A modified form of the Adomian decomposition method will be implemented to construct such solutions. The approach provides the solution in the form of a rapidly convergent series. The analysis is accompanied by numerical examples. The obtained results demonstrate reliability and efficiency of the proposed scheme.
An Alternating-Direction Sinc-Galerkin method for elliptic problems

A new Alternating-Direction Sinc-Galerkin (ADSG) method is developed and contrasted with classical Sinc-Galerkin methods. It is derived from an iterative scheme for solving the Lyapunov equation that arises when a symmetric Sinc-Galerkin method is used to approximate the solution of elliptic partial differential equations. We include parameter choices (derived from numerical experiments) that simplify existing alternating-direction algorithms. We compare the new scheme to a standard method employing Gaussian elimination on a system produced using the Kronecker product and Kronecker sum, as well as to a more efficient algorithm employing matrix diagonalization. We note that the ADSG method easily outperforms Gaussian elimination on the Kronecker sum and, while competitive with matrix diagonalization, does not require the computation of eigenvalues and eigenvectors.
Quality of Life Issues in a Casino Destination

Abstract Gambling is spreading across North America. Debate has accompanied this diffusion. This study: (1) describes attitudes held by Nevada residents about the effects of legalized gambling and (2) identifies the relationship among resident characteristics, perceptions of the impact gaming has had in Nevada, and perceived quality of life (QOL). Residents recognize that legalized gambling has brought both benefits and costs. Among interesting correlates, individuals with less education and urban residents perceived more social costs from legalized gaming. Perceived social costs are negatively correlated with QOL, whereas perceived job growth is positively correlated with QOL. These impacts are similar to those reported for other forms of mass tourism, and the data suggest that equity issues need further investigation.
A thyroxine-containing thyroglobulin peptide induces both lymphocytic and granulomatous forms of experimental autoimmune thyroiditis

Mouse thyroglobulin (MTg)-sensitized spleen cells activated in vitro with MTg can induce two histologically distinct forms of experimental autoimmune thyroiditis (EAT). MTg-sensitized cells activated with MTg alone induce a mild chronic form of EAT in which the thyroid infiltrate consists primarily of lymphocytes and other mononuclear cells (lymphocytic EAT). The same donor cells activated with MTg and anti-IL2R mAb induce a more severe and acute form of EAT with a thyroid inflammatory lesion having granulomatous histopathological features. A thyroxine-containing (T4) peptide, corresponding to positions 2549-2560 of human Tg, was shown by others to activate spleen cells of mouse thyroglobulin (MTg)-sensitized CBA/J mice to induce lymphocytic EAT. To determine if the CD4+ effector T cells that induce granulomatous EAT can respond to the same T-cell epitope, the present study was undertaken to determine if both forms of EAT could be induced by the 2549-2560 thyroxine (T4)-containing peptide. This peptide was very effective for activation of T cells from MTg-primed CBA/J donors to induce granulomatous EAT but, in contrast to MTg, did not activate T cells from AKR/J or DBA/1 mice to induce granulomatous EAT. The T4 peptide did not apparently activate peptide-specific B cells in vivo but did activate MTg-primed B cells in vitro to produce anti-MTg autoantibody in recipient mice. These results demonstrate that a single 12-amino-acid thyroxine-containing peptide can activate T cells from CBA/J mice to induce both lymphocytic and granulomatous EAT. However, this peptide does not activate T cells from some other EAT-susceptible strains of mice, suggesting that MTg contains multiple epitopes able to activate T cells to induce granulomatous EAT.
Determinants of child care mode choice: An economic perspective

The author presents evidence indicating that economic and demographic variables are important determinants of the type of child care used by two-earner households. Three conclusions follow from the empirical analysis: (a) Projections for future child care needs could be considerably impoved if, rather than taking into account only the number of children under 6, as done presently, more detailed age categories were considered, as well as trends in male and female wages and labor supply. (b) Subsidies to the formal modes of care may have antinatalist consequences. (c) Unless income tests are used, the benefits from such subsidies are likely to be heavily concentrated in the high-income groups.
Effects of nicotine on weight change and food consumption in rats.

The present study was designed to test the effects of nicotine and nicotine withdrawal on weight change and food consumption in rats. Twelve male and 12 female three month old Sprague-Dawley rats were divided 3nto three treatment groups: 0.2, 0.4, and 0.6 mg nicotine/kg body wt. Half were given subcutaneous nicotine treatment for three weeks and then saline for three weeks; treatment sequence was reversed for the other half. Injections were administered three times daily throughout the experimental period. Prior to treatment, baseline measures were established for both food consumption and weight. Mean differences in weight change were calculated on a weekly basis throughout the experiment. Overall tests indicate that nicotine withdrawal produced significant (p<0.05) weight gains and nicotine administration produced inhibition of weight gain. A significant sex × drug × time interaction (p<0.05) demonstrated that food consumption increased when nicotine was discontinued and decreased when nicotine was administered. Specific comparison tests showed these effects on food consumption and weight were strongest at the 0.6 level and that larger effects were obtained for males than for females.
A divergence-free Chebyshev collocation procedure for incompressible flows with two non-periodic directions

Abstract The enforcement of divergence-free condition in the interior and on the boundaries of an incompressible flow with two non-periodic directions is discussed for a Chebyshev collocation formulation. An influence matrix technique along with a correction methodology is used to satisfy the continuity equation everywhere in the domain. Details of implementing this procedure in a collocation method are presented. An efficient solution procedure based on matrix diagonalization has been used to solve the resulting full matrices. Two test problems: (a) flow in a driven square cavity, and (b) fully-developed laminar flow in a square duct subject to a three-dimensional perturbation are studied. Run-time statistics (CPU, memory, MFLOPS) of the solution procedure are presented for representative grid sizes.
A Reanalysis of the Ultraviolet Extinction from Interstellar Dust in the Large Magellanic Cloud

We have reanalyzed the Large Magellanic Cloud's (LMC) ultraviolet (UV) extinction using data from the IUE final archive. Our new analysis takes advantage of the improved signal-to-noise ratio of the IUE NEWSIPS reduction, the exclusion of stars with very low reddening, the careful selection of well-matched comparison stars, and an analysis of the effects of Galactic foreground dust. Differences between the average extinction curves of the 30 Dor region and the rest of the LMC are reduced compared with previous studies. We find that there is a group of stars with very weak 2175 A bumps that lie in or near the region occupied by the supergiant shell, LMC 2, on the southeast side of 30 Dor. The average extinction curves inside and outside LMC 2 show a very significant difference in 2175 A bump strength, but their far-UV extinctions are similar. While it is unclear whether or not the extinction outside the LMC 2 region can be fitted with the relation of Cardelli, Clayton, & Mathis (CCM), sight lines near LMC 2 cannot be fitted with CCM because of their weak 2175 A bumps. While the extinction properties seen in the LMC lie within the range of properties seen in the Galaxy, the correlations of UV extinction properties with environment seen in the Galaxy do not appear to hold in the LMC.
Behavioral disruption versus signal-generated memory retrieval as determinants of the signal-generated partial reinforcement extinction effect

In both experiments reported here, two groups of rats, Groups Signal-N and Disrupt, received runway discrimination training in Phase 1 to establish a stimulus as a signal for nonreinforcement (N). Group CRF received reinforcement throughout Phase 1. All subjects received consistent reinforcement throughout Phase 2. On 50% of Phase 2 trials, Group Signal-N experienced the signal for nonreinforcement, and Group Disrupt experienced a novel stimulus. Both stimuli disrupted responding. In Experiment 1, the signal for N was a tactile cue, and the disruptive stimulus was a pretrial feeding. This arrangement was reversed in Experiment 2. In both experiments, Group Signal-N showed increased resistance to extinction, relative to Group CRF—a difference that defines the signal-generated partial reinforcement extinction effect (PREE) (Haggbloom, 1988). Resistance to extinction was not increased in Group Disrupt. The results indicate that the signal-generated PREE is not due simply to counterconditioning to behaviorally disruptive stimuli.
Differential and simultaneous adenosine di- and triphosphate binding by MutS.

The roles of ATP binding and hydrolysis in the function of MutS in mismatch repair are poorly understood. As one means of addressing this question, we have determined the affinities and number of adenosine di- and triphosphate binding sites within MutS. Nitrocellulose filter binding assay and equilibrium fluorescence anisotropy measurements have demonstrated that MutS has one high affinity binding site for ADP and one high affinity site for nonhydrolyzable ATP analogues per dimer equivalent. Low concentrations of 5'-adenylylimidodiphosphate (AMPPNP) promote ADP binding and a large excess of AMPPNP is required to displace ADP from the protein. Fluorescence energy transfer and filter binding assays indicate that ADP and nonhydrolyzable ATP analogues can bind simultaneously to adjacent subunits within the MutS oligomer with affinities in the low micromolar range. These findings suggest that the protein exists primarily as the ATP.MutS.ADP ternary complex in solution and that this may be the form of the protein that is involved in DNA encounters in vivo.
Explaining Distributions of Psychological Vulnerability: Lack of Social Support in the Face of Life Stress

This paper tests the hypothesis that the psychological vulnerability of disadvantaged persons to undesirable life events can be explained by the joint occurrence of high event exposure and low social support resources in such persons' lives. Data from a panel study of 1,106 individuals in Chicago are utilized to examine this hypothesis. Social support is operationalized as the relative presence or absence of an intimate, confiding relationship. Analyses show that differential vulnerability cannot be accounted for by the joint occurrence of undesirable events and lack of support. A significant negative main effect of social support on psychological distress is revealed, suggesting that support counterbalances, rather than interacts with (buffers), the impacts of life stress. Explanations for these findings are offered.
The Surveyor Lunar Landings

Surveyor lunar landing procedures and results including instrumentation, lunar topography, selenology, chemical and physical properties, solar corona and earth laser output observations
Chirp on crickets: teaching compilers using an embedded robot controller

Traditionally, the topics of compiler construction and language processing have been taught as an elective course in Computer Science curricula. As such, students may graduate with little understanding or experience with the useful techniques embodied in modern compiler construction.In this paper, we present the design of Chirp, a language specification and compiler implementation. As a language, Chirp is based on Java/C syntax conventions and is matched with the stack-based virtual machine that is built into the simple yet versatile Handy Cricket educational robot controller. As a compiler, the Chirp design is a series of Java components. These modules demonstrate key compiler construction techniques including lexing, parsing, intermediate representation, semantic analysis, error handling and code generation.We have designed a 6-week teaching module to be integrated into an intermediate-level undergraduate programming class. In the module, students will incrementally build the Chirp compiler, culminating with code generation for the Cricket controller. They will test their work on both physical Cricket-based robots and a web-based Cricket simulator. The Chirp system and our pedagogical design provides a realistic and engaging environment to teach compilers in undergraduate core programming courses.