cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis of a ligand based upon a new entry into the 3-hydroxy-N-alkyl-2(1H)-pyridinone ring system and thermodynamic evaluation of its gadolinium complex.

The synthesis of a new, more water soluble derivative of TREN-Me-3,2-HOPO {tris[(3-hydroxy-1-methyl-2-oxo-1,2-didehydropyridine-4-carboxamido)ethyl]amine} is presented. The synthesis starts with the condensation reaction of (N-methoxyethylamino)acetonitrile hydrochloride and oxalyl chloride to give 3,5-dichloro-N-(methoxyethyl)-2(1H)-pyrazinone. The 3-position is readily substituted with a benzyloxy group, and the pyrazinone is converted to ethyl 3-(benzyloxy)-N-(methoxyethyl)-2(1H)-pyridinone-4-carboxylate by a Diels−Alder cycloaddition with ethyl propiolate. Basic deprotection of the ester followed by activation, coupling to tren, and acidic deprotection of the benzyl groups gives the ligand TREN-MOE-3,2-HOPO {tris[(3-hydroxy-1-(methoxyethyl)-2-oxo-1,2-didehydropyridine-4-carboxamido)ethyl]amine}. The gadolinium complex of TREN-MOE-3,2-HOPO was prepared by metathesis, starting from gadolinium chloride. The solubility of the new metal complex is significantly enhanced. The four protonation constants (det...
Uncertainty Quantification, Sensitivity Analysis, and Data Assimilation for Nuclear Systems Simulation

Reliable evaluation of nuclear data will play a major role in reduction of nuclear systems simulation uncertainties via the use of advanced sensitivity analysis (SA), uncertainty quantification (UQ), and data assimilation (DA) methodologies. This follows since nuclear data have proven to constitute a major source of neutronics uncertainties. This paper will overview the use of the Efficient Subspace Method (ESM), developed at NCSU, to overcome one of the main deficiencies of existing methodologies for SA/UQ/DA, that is the ability to handle codes with large input and output (I/O) data streams, where neither the forward nor the adjoint approach alone are appropriate. We demonstrate the functionality of ESM for an LWR core, a boiling water reactor, and a fast reactor benchmark experiment, the ZPR6/7A assembly. This work demonstrates the capability of adjusting cross section data thereby providing guidance to cross section evaluation efforts by identification of key cross sections and associated energy ranges that contribute the most to the propagated core attributes uncertainties.
Maternal drug use, personality, child-rearing practices, and toddlers' sadness.

Summary.-We investigated the influence of maternal drug use/personaliry attributes and child-rearing on 2-yr.-olds' sadness. The sample consisted of 62 girls and 53 boys and their mothers. Analysis showed maternal parenting practices served as a mediator for the effect of the mothers' personalities on the children's Feelings of sadness. Moreover, the mothers' persondty traits of low interpersonal dSiculty, anxiety, and depression were important in enhancing low maternal alcohol or illegal drug use, leading to less sadness in the children. This study investigated the influence of maternal personality/drug use attributes and child-rearing on 2-yr.-old toddlers' sad mood. The sample consisted of 62 girls and 53 boys and their mothers. The mothers were administered separate interviews about their person&ty/dmg use attributes, relations with their children, and the children's intrapsychic functioning. The dependent variable was the children's sadness (e.g., long periods when the child is sad or unhappy). The independent measures of maternal traits were grouped into two domains, drug-prone personahty attributes and drug use and mother-child relationships. The measures appear in Table 1 and were described in the work of Brook, Brook, Whiteman, and Cohen (1990). Pearson correlations between the maternal personahty/drug use and the children's sadness are presented in Table 1. The values show that mothers' personality traits of high impulsivity, interpersonal difficulty, sensation seeking, and anxiety were Med to sadness in the children. That is, a pattern of poor emotional control, difficult interpersonal relations, and poor intrapsychic functioning contributed to the children's sadness. As regards maternal parenting techniques, the findmgs suggest that a close mother-child attachment and low use of power-assertive discipline methods on the children insulated the children from sadness. Consistent with the fiidmgs of the present study, several researchers (e.g., Crowell, O'Connor, Wollmers, Spraflun, & Rao, 1991) reported that maternal attachment was associated with children's low depression.
A covert complication of arteriovenous fistulas

Abstract Our patient is a 65-year-old man with a history of hypertension, aortic stenosis, and end-stage renal disease on hemodialysis who presented with worsening dyspnea. On examination, he exhibited signs of volume overload and had a radiocephalic arteriovenous fistula (AVF) with a significantly palpable thrill. Coronary angiogram showed normal coronary arteries. Cardiac catheterization revealed a cardiac output of 10.6L/min by thermodilution. Ultrasound of the AVF access demonstrated an abnormally high velocity with flow >5L/min. The patient was diagnosed with high-output heart failure (HOHF) secondary to his arteriovenous fistula. HOHF is an uncommon entity associated with certain pathologic states such as hyperthyroidism, skeletal and dermatologic disorders. It is defined as a high cardiac output >8L/min, resting cardiac index >2.5–4.0L/min per m 2 , and low systemic vascular resistance. Cardiac catheterization is often required for definitive diagnosis. The increased cardiac output may result in overt heart failure in patients with underlying heart disease. Treatment of HOHF secondary to an extracardiac shunt involves flow reduction procedures, ligation, or peritoneal dialysis. Our patient was successfully treated with AVF banding. Early recognition of this complication is critical, as many cases are reversible. Learning objective: High-output heart failure, defined as cardiac output >8L/min, resting cardiac index >2.5–4.0L/min per m 2 and low systemic vascular resistance, is an uncommon entity associated with conditions such as hyperthyroidism, skeletal disorders, and dermatologic disorders. It is an often-missed complication in patients with arteriovenous fistulas, particularly those with underlying heart disease. The Kidney Foundation guidelines recommend arteriovenous fistula monitoring by physical examination and monthly flow measurements for patients at risk.>
UV-curable PUDs based on sustainable acrylated polyol: Study of their hydrophobic and oleophobic properties

Abstract UV-curable polyurethane dispersions (UV-PUDs) are fast expanding commercial applications since they combine benefits of both water-borne as well as UV-curing technologies while addressing many technical, environmental and performance benefits. Varying the compositions and cross-link density of UV-PUD polymeric chain backbone can control the film properties of UV-PUDs. There are many design restrictions posed by availability of commercial materials. In the present research work we demonstrate synthesis and application of a multi-functional acrylate polyol derived from soybean oil, as soft-segment of UV-PUDs. A series of UV-PUDs have been designed for high performance coatings that are specifically hydrophobic and oil-resistant. To this end, UV-PUDs based on acrylated soy-polyol have been further modified by siloxane and perfluoro compounds and their films with varying cross-link density have been investigated. The UV-PUD films were characterized for their film properties, particle size, contact angle and solvent swelling ratio. The outcome of this study provides useful insights into design considerations for hydrophobic and oil-resistant UV-curable coatings.
Lightwand intubation of infants and children

Abstract Study Objective: To examine factors contributing to successful lightwand (lighted stylet) intubation of infants and children. Design: Prospective observational study. Setting: University hospital. Patients: 125 children under age 10 years presenting for elective surgery. Interventions: Prototype lightwands specifically designed for pediatric patients were used. Intubations were done by anesthesia residents with little or no prior lightwand experience. All attempts were recorded on videotape. In a subgroup of 14 patients, an endoscopic view of the lightwand was also recorded with a flexible nasopharyngoscope. Measurements and Main Results: 125 patients with a mean age of 3.0 years (±2.4 years SD; range: 3 weeks to 9 years) were enrolled. 83.2% were intubated using the lightwand, including 75.5% (34 of 45) of infants weighing less than 10 kg. Of the 21 failed intubations, 8 were due to an inappropriately large endotracheal tube, as recognized during direct laryngoscopy; 4 were due to other reasons discussed; and 9 (persistent vallecular or esophageal entry) could not be explained from videotape analysis. Factors contributing to successful intubation included: (1) use of a shoulder roll and slight head extension; (2) conscientious alignment of airway axes; (3) anterior jaw lift to elevate the epiglottis; and (4) gentle handling of the lightwand to avoid displacing soft tissue. Inability to advance the lightwand despite correct glow is caused by entrapment in the vallecula, hang up of the lightwand on the aryepiglottic folds, subglottic narrowing, or vocal cord closure. Conclusions: Lightwand intubation in children uses both tactile and visual cues regarding the location of the endotracheal tube tip. Attention to detail results in a high level of success among novice users of the pediatric lightwand. Endoscopic and external videotaping gave us a means of monitoring the progress of mechanical skills among novice users.
Effect of Plate Inclination on Natural Convection From a Plate to Its Cylindrical Enclosure

Etude par interferometrie holographique. Determination des coefficients de transfert de chaleur
A NEW OPEN AND CLOSED RESPIRATION CHAMBER

A new, fully automated, open and closed respiration chamber has been constructed, which is large enough to accommodate man or comparable sized animals. Metabolic rate is calculated from measured changes in respiratory gas volumes while the system is hermetically sealed. When CO2 concentration reaches a prescribed level, large ports are opened and the chamber is ventilated. By repeating this process, a series of metabolic determinations can be conducted over an extended period. Temperature, humidity and air velocity are fixed, but chamber volume and pressure vary with changes in the respiratory exchange of the animal and/or barometric pressure. Small, rapid changes in gas volumes are monitored by a low-resistance spirometer and large changes accommodated in a second, high-volume, motorized spirometer. Chamber operations, data acquisition and metabolic calculations are performed by a small computer. System calibration with methanol combustion indicates that estimates of respiratory gas exchange are highly accurate over a temperature range from 10-40 degrees C.
The Male Hormone Content of Ruminant Manure

Summary The male hormone (androgen) content of ruminant manure was assayed biologically by feeding it as part of the starter ration to groups of White Plymouth Rock chicks during a period of 28 days. The average comb weight of 40 chicks fed 10 per cent dried manure from lactating cows was 225.2mg. in comparison to the comb weight of normal chicks of 61.3mg. Lactating cow manure dried at temperatures ranging from 45° C. to 85° C. by 10 degree intervals gradually declined in androgen potency. At temperatures of 75° C. and above all biological activity was lost. The androgen content of the manure of other ruminants including goats and sheep of both sexes and conditions was either low or absent. The manure of dairy bulls showed indications of only small androgen excretion by that route. Chicks fed methyl testosterone at the rate of 20mg. per kg. of feed had combs averaging 233.8mg. This is comparable to the effect of lactating-cow manure fed at the 10 per cent level or 100gm. per kg. of feed. The point of entrance of the androgenic hormone into the digestive tract of the cow has not yet been determined.
Simulation of graded-base bipolar transistor characteristics fabricated with a focused ion beam

Abstract Focused ion beam (FIB) technology enables for the first time the design of bipolar junction transistors (BJT) with horizontally-graded base. In this paper we present a theoretical analysis of BJT operation for various grading profiles. Two key device characteristics, current gain and base resistance, are calculated and compared to the conventional uniform doping profile case in both low-and high-level injection. An inverted triangular doping profile is shown to result in performance superior to the conventional (uniform) base doping.
Sperm storage and use in laboratory-reared Aplysia californica , a simultaneous hermaphrodite

Aplysia californica, an opisthobranch mollusc, possesses a complex reproductive system that includes a seminal receptacle for the storage of exogenous sperm received from mating. Based on this reproductive anatomy, A. californica should have the ability to maintain and use viable exogenous sperm stores to fertilize multiple eggmasses for extended periods of time. Using controlled matings and careful observation of the development of eggmasses over time, we attempted to quantify A. californica’s ability to store and use exogenous sperm following a single mating. On average, A. californica (240.6±31.7 g; mean±SE, n=9) produced 8.8±0.6 eggmasses containing 16.9±2.2×106 fertilized eggs over a period of 22.3±3.6 days following a single mating encounter. The maximum duration an individual A. californica produced fertilized eggs, following a single copulation, was 41 days. The primary factor determining the cumulative number of fertilized eggs produced from a single mating in A. californica was the mass of the sperm recipient (r=0.773, P<0.05, n=9). Our results demonstrated that A. californica are not sperm limited following a single mating as has been suggested for other opisthobranch molluscs by Leonard and Lukowiak’s (1991) gamete-trading hypothesis.
Re-framing information literacy: Problem-based learning as informed learning

Abstract This study explores an online information literacy module that uses problem-based learning (PBL). The goal was to enable students to experience information literacy in a richer way, by moving away from a focus on locating information sources to one of information use in the construction of knowledge. A content analysis of the research journals and reflection papers of students ( N = 15) in a distance education school library media administration endorsement program suggests that PBL was an effective approach for some students, but not others. Some students were motivated by working on authentic problems, and at least half the students engaged deeply with information and discovered new questions and angles for research during the process. These students applied more sophisticated evaluation strategies and were more metacognitive in their thinking, assessing their progress and shifting strategies as they progressed through the module.
The movement from ethics to social relationships for Levinas, and why decency obscures obligation

According to Emmanuel Levinas, the individual bears an infinite obligation to the other person. In the Talmudic reading “Judaism and revolution,” Levinas suggests that we move from the ethical encounter (and infinite obligation) to social relationships (with limited obligations) using contracts—both particular contracts and the social contract. So social relationships are created by limiting obligation, and as a result these relationships can only be practically acceptable, not ethical. Jewish religious practice for Levinas should also be understood as a set of negotiated limits to our infinite obligation.
Numerical Simulation of phytoplankton productivity in partially mixed estuaries

Abstract A two-dimensional steady-state model of light-driven phytoplankton productivity and biomass in partially mixed estuaries has been developed. Effects of variations in river flow, suspended sediment concentration, phytoplankton sinking, self-shading and growth rates on distributions of phytoplankton biomass and productivity are investigated. Numerical simulation experiments show that biomass and productivity are particularly sensitive to variations in suspended sediment concentrations typical of natural river sources and to variations in loss rates assumed to be realistic but poorly known for real systems. Changes in the loss rate term within the range of empirical error (such as from dark bottle incubation experiments) cause phytoplankton biomass to change by a factor of two. In estuaries with adequate light penetration in the water column, it could be an advantage for phytoplankton to sink. Species that sink increase their concentration and form a phytoplankton maximum in a way similar to the formation of the estuarine turbidity maximum. When attenuation is severe, however, sinking species have more difficulty in maintaining their population.
An auction behavior-based robotic architecture for service robotics

Service robots have the potential of improving the quality of life and assist with people's daily activities. Such robots must be capable of operating over long periods of time, performing multiple tasks, and scheduling them appropriately for execution. In addition, service robots must be capable of dealing with tasks whose goals may be in conflict with each other and would need to determine, dynamically, which task to pursue in such a case. Adding to the complexity of the problem is the fact that some task requests may have time constraints--deadlines by which the task has to be completed. Given the dynamic nature of the environment, the robots must make decisions on what tasks to pursue in situations where there could be incomplete or missing information. The robots should also be capable of accepting requests for new tasks or services at runtime, while possibly working on another task. In order to achieve these requirements, this paper presents the Auction Behavior-Based Robotic Architecture that brings the following contributions: (1) it uses an auction mechanism to determine the relevance of a task to run at any given time, (2) it handles multiple user requests while dealing with potentially critical time constraints and incomplete information, (3) it enables long-term robot operation and (4) it allows for dynamic assignment of new tasks. The proposed system is validated on a physical robotic platform, the Segway RMP $$^{\circledR }$$ ® and in simulation.
A method of determining charged-particle beam composition

Abstract We describe a method which efficiently and precisely determines the relative content of electrons/positrons, muons, and hadrons in a high-energy beam of charged particles, over a wide momentum range. There is no discrimination between hadrons of a given charge and momentum. As an example, we cite the determination of electron and pion contaminations in a 14 GeV SLAC muon beam, to a precision of ∼10 −5 .
Effect of pyrazole in vivo on aldehyde metabolism in rat liver and brain.

Abstract The effect of administration of pyrazole in vivo on aldehyde reduction and oxidation has been studied in rat liver and brain. It was found that while pyrazole is capable of complete inhibition of NADH dependent reduction of a number of aldehydes in liver, it is only partially effective as an inhibitor of NADPH dependent aldehyde reduction and is ineffective as an inhibitor of NAD dependent aldehyde oxidations in liver. No effect of pyrazole on oxidation or reduction of aldehydes in brain was found. Pyrazole has a rapid onset of action in vivo and has an effective half life for inhibition of NADH dependent aldehyde reduction in rat liver of about 76 hr following a dose of 360 mg × kg−1 intraperitoneally.
Effect of scale on liquid recirculation in bubble columns

Abstract Successful scale-up of liquid hydrodynamics in bubble columns using a one dimensional model requires an adequate closure scheme for the Reynolds shear stress. The existing correlations for the prescription of the eddy viscosity or the mixing length scale are demonstrated to be applicable only for a limited range of conditions and consequently cannot be used for scale-up predictions. A method for estimating the mixing length scale has been explored and an attempt at unifying a wide range of data available in the literature within the purview of the method has been made. The futility of such an attempt is attributed to the nonreproducibility of the flow in different laboratories and the consequent lack of data obtained under identical conditions. It is demonstrated, however, that scale-up based on the mixing length distribution is possible when it is obtained from a consistent set of data for liquid velocity and gas void fraction profiles. Such a data set was obtained in the author's laboratory using CARPT (Computer Automated Radioactive Particle Tracking) and CT (Computed Tomography). Using the present method for prescribing the mixing length scale, model predictions for scale-up compare satisfactorily for the data that were obtained in the author's laboratory.
Liver transplantation for growing teratoma syndrome: Report of a case

Liver transplantation is a well-established treatment for liver failure and for a selected group of patients with hepatic tumors. The growing teratoma syndrome refers to the phenomenon whereby germ cell tumors enlarge after chemotherapy despite complete eradication of malignant cells and normalization of serum tumor markers. We present the case of a young patient with rapidly growing teratomatous masses in his liver who was treated with liver transplantation from a live donor. We discuss his postoperative management, follow-up, and briefly review literature on the subject.
Periodate induced lymphocyte transformation. I. Inhibition by sulfhydryl reducing agents and sugars.

Sodium metaperiodate stimulates human small lymphocytes to transform into blast cells which synthesize DNA. The triggering of this lymphocyte activation occurs within minutes, but can be blocked by pre-treatment of the periodate with reducing agents. The inhibition of the periodate effect on lymphocytes does not appear to be due to toxic or inhibitory substances produced by the interaction between periodate and reducing agents. The results suggest that the mechanism of action of periodate upon the lymphocytes involves an oxidatlon-reduction reaction, conceivably involving carbohydrate moieties or sulfhydryl groups at the cell surface. Specificity is indicated by the negative response obtained with other oxidizing agents and iodine compounds. The use of periodate in elucidating the triggering action involved in the induction of lymphocyte transformation appears to have significant value.
Photon-Driven Chemistry of Biacetyl on Ag(111)

The photon-driven chemistry of biacetyl (CH3COCOCH3) on Ag(111) has been studied using temperature-programmed desorption, Auger electron spectroscopy, and time-of-flight mass spectrometry. Irradiation of both monolayer and multilayer biacetyl with 193 nm photons results in the prompt ejection of CH3 radicals that exhibit bimodal translational temperatures of 2700 ± 100 and 290 ± 20 K. Irradiation of multilayer biacetyl with 193 nm also leads to ejection of CO with translational temperatures of 1170 ± 40 and 140 ± 10 K, ketene (CH2CO) with translational temperatures of 1000 ± 60 K, and acetyl-containing fragments with translational temperatures of 320 ± 20 K. Indicative of the ejection of all reaction products from the surface during irradiation, postirradiation TPD shows loss of parent only, and C(a) and O(a) are absent from the surface after irradiation and subsequent heating to 700 K. The cross section for total loss of 1 ML biacetyl is 2.0 ± 0.3 × 10-21 cm+2 at 193 nm. Studies using 248 nm radiation, a...
Labour Migration in Colonial Tanzania and the Hegemony of South African Historiography

It is argued that the migration and work culture model in South Africa does not apply to Tanzanian labor migration to European plantations under German rule. The model in South Africa should not be considered representative of Africa. Tanzanian social structures and patterns of colonialism were fundamentally different from South Africas. There were differences in the nature of capital penetration the participation of peasants in shaping the colonial economy and the role of women. Labor migrants in Tanzania had control of the patterns of production at work and thus affected the colonial labor system. Workers did not suffer from patterns of repressive taxation and collaboration between the government African elites district officials and settlers against migrants. Changes were made by German colonials after the Maji Maji uprising. Peasants productivity was encouraged as a means of increasing production. The policy gave peasants leverage in the labor migration process. Peasants used short-distance labor migration as a household survival strategy. Migrants settled in societies where caravan porterage was a tradition. After 1909 planters continued to recruit women and children. Peasants created their own societies on rural plantations. In Tanzania the laws did not reflect "time discipline" industrial labor patterns but did deal with plantation issues such as duration of contracts. The tax policy after 6 months of work relieved peasants of the tax burden. Labor recruiters and plantation owners to some extent used coercive means to secure workers. Migrants selected the work site carefully and examined food rations plantation upkeep recruitment fees food during the march to the work site and the reputations of plantations. The labor migration in Tanzania was far less repressive than in South Africa. Migrants collectively worked to improve their living conditions before returning to their core villages.
Power considerations for testing an interaction in a 2 × k factorial design with a failure time outcome

Abstract We examine the power and sample size requirements for testing an interaction in the situation of a 2 × k factorial design with time to failure as the outcome of interest. Using the distribution of a general test statistic, based on a weighted residual sum of squares for testing a general interaction in a 2 × k factorial experiment, we describe the relationship between the power of the test and the size of the sample. In a Simulation study, we evaluate the behavior of three commonly used estimators as methods for estimating the parameters of the test statistic. These are the Mantel-Haenszel (MH) method, a method (O/E) based on the ratio of the observed to expected number of events, and the maximum likelihood (MLE) method. We show that in most cases nominal test sizes and appropriate powers are attained using the MLE and MH methods, whereas the O/E method yielded test sizes and powers less than expected. With both large baseline hazard rates and large differences in relative hazard rates, the difference between the simulated and asymptotic powers for all three methods become larger; however, the size of this difference is small and unlikely to seriously affect the use of either the MLE or MH methods. The proposed methods could also be used to calculate the power and sample size for testing a treatment-covariate interaction in a stratified data analysis.
Aromatization is not required for androgen induced changes in proopiomelanocortin gene expression in the hypothalamus

Abstract Testosterone regulation of POMC mRNA and peptide levels has been previously demonstrated in the medial basal hypothalamus (MBH) of the rat. Although both dihydrotestosterone (DHT) and estradiol are known to affect POMC peptide levels in the MBH, it is unclear if the effects of testosterone on POMC gene expression are due to conversion by aromatization to estradiol or due to independent androgen actions. We have therefore compared the effects of the nonaromatizable androgen DHT and estradiol on POMC gene expression and β-endorphin (β-EP) levels in the MBH of castrated male rats. We have also examined the effect of the dopamine agonist, pergolide, on POMC in the DHT and estradiol treated animals in light of previous studies in female rats. In the first study POMC mRNA in the MBH, as measured by a solution hybridization assay, was 0.85 ± 0.07 pg/μg RNA 3 weeks after castration and decreased to 0.64 ± 0.07 pg and 0.65 ± 0.07 pg in the DHT treated rats with and without pergolide (P
Quantifying the severity of acute lung injury using dead-space ventilation: should the lung injury score be updated?

During the past decade of research on acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) there has been heightened interest in measuring physiologic dead-space fraction (VD/VT). Since ARDS first was described 44 years ago, the primary focus on gas exchange abnormalities concerned
The composition and diagenesis of interstitial solutions—I. Fluxes across the seawater-sediment interface in the Atlantic Ocean

Abstract Studies of the composition of interstitial solutions of marine sediments have been carried out utilizing in situ sampling techniques. Samples were obtained from the Caribbean, North Atlantic and South Atlantic. In virtually all cases, diagenesis has led to the uptake of Mg 2+ and K + and the release of Ca 2+ , HCO − 3 and Na + by the solid phases. SO 2− 4 is slightly enriched at nearly all stations, reduction being observed only at continental margin stations. Cl − is conservative within experimental precision. The reactions controlling the fluxes of most components across the water-sediment interface occur almost entirely in the upper 100 cm of sediment. Contributions of Mg 2+ , Ca 2+ , K + and HCO − 3 from below 100 cm amount to less than 15% of the calculated fluxes across the interface. Reactions in the upper 30 cm account for 70–90% of the fluxes of these components across the interface. Only Na + has a deep source, gradients often being linear in the upper 2m of sediment. Calculated fluxes across the sediment-water interface are of the same order of magnitude as river inputs for the components studied. In the case of Mg 2+ and K + , 60–100% of the river input can be balanced by diagenetic uptake in the sediment. For Ca 2+ and HCO − 3 additions to seawater augment the river supply by 25–50%. When the uptake of Mg 2+ and K + by the sediment is calculated by integrating the fluxes across the interface, calculated concentrations of both of these elements are inconsistent with published average concentrations for the types of sediment studied.
Mass and charge measurement of trapped dust in the CESR storage ring

Abstract The trapping of dust particles with an attendant reduction in beam lifetime and/or increased radiation rates is aperiodically observed in the Cornell Electron/positron Storage Ring CESR. A measurement of the stability of the trapped dust as a function of bunch current with a single bunch of electrons confirmed directly that the dust particles are heavier than any normal constituent of the residual gas in the vacuum chamber. The removal of individual dust particles from the beam via image charge forces were observed and the change in beam lifetime together with the current at which the dust left the beam permitted calculation of the dust mass and charge. The surface electric field of the dust particle as calculated from the experimental data agrees well with a theoretical calculation based upon an equilibrium between charging and discharging rates.
Nonlinear Free-Surface Effects on a Submerged Sphere

Nonlinear effects on the wave-induced forces acting on a submerged sphere in a steady translation are investigated. A recent endeavor by Tuck indicates that in the case of a submerged cylinder the forces due to the nonlinearity of the free surface are quite discernible in comparison with the second-order forces derived from the linearized homogeneous freesurface condition. The purpose of the present work is to assess the influence of the nonlinearity upon a three-dimensional water-wave problem.
Conditional Dicer Substrate Formation via Shape and Sequence Transduction with Small Conditional RNAs

RNA interference (RNAi) mediated by small interfering RNAs (siRNAs) enables knockdown of a gene of choice, executing the logical operation: silence gene Y. The fact that the siRNA is constitutively active is a significant limitation, making it difficult to confine knockdown to a specific locus and time. To achieve spatiotemporal control over silencing, we seek to engineer small conditional RNAs (scRNAs) that mediate ‘conditional RNAi’ corresponding to the logical operation: if gene X is transcribed, silence independent gene Y. By appropriately selecting gene X, knockdown of gene Y could then be restricted in a tissue- and time-specific manner. To implement the logic of conditional RNAi, our approach is to engineer scRNAs that, upon binding to mRNA ‘detection target’ X, perform shape and sequence transduction to form a Dicer substrate targeting independent mRNA ‘silencing target’ Y, with subsequent Dicer processing yielding an siRNA targeting mRNA Y for destruction. Toward this end, here we design and experimentally validate diverse scRNA mechanisms for conditional Dicer substrate formation. Test tube studies demonstrate strong OFF/ON conditional response, with at least an order of magnitude increase in Dicer substrate production in the presence of the cognate mRNA detection target. By appropriately dimensioning and/or chemically modifying the scRNAs, only the product of signal transduction, and not the reactants or intermediates, is efficiently processed by Dicer, yielding siRNAs. These mechanism studies explore diverse design principles for engineering scRNA signal transduction cascades including reactant stability vs metastability, catalytic vs noncatalytic transduction, pre- vs post-transcriptional transduction, reactant and product molecularity, and modes of molecular self-assembly and disassembly.
Some problems associated with interactive graphics in computer mediated tutorials

Whether one is talking about the verbal or graphic aspects of a computer mediated tutorial, there are two prime considerations. (1) How easy is it for the medical teacher to input the information? (2) How closely does the interaction with the student approximate a free format tutorial?Our experience has gone through two distinct phases. For the first two years we worked with the IBM 1500 System and its associated language COURSEWRITER II (1). The 1500 has both a CRT with light pen and a random access, computer addressed, 35mm film strip projector.For the past two years we have been working with APL/360 and an IBM 2741 Communications Terminal with no graphic capabilities. Using APL we have developed a new (author) programming language called ATS (A Tutorial System) (2,3,4).Our purpose here today is to focus on the two aspects of a computer mediated tutorial already mentioned. Because of the nature of our personal experience, we would like to compare the problems (both the similarities and differences) associated with handling verbal and graphic input. The discussion will be divided into the following major topics. (1) A brief description of the 1500 System and our contributions to it.This work has been documented previously. (2) Interfacing the medical author with the computer. (3) Providing the machine with the intelligence to handle free format interactions with the student. (4) A word about encoding verbal and graphic information.
THE DISORGANIZATION OF HEPATIC CELL NUCLEOLI INDUCED BY ETHIONINE AND ITS REVERSAL BY ADENINE

The structure of nuclei and nucleoli of hepatic cells after short-term ethionine administration was investigated with the electron microscope. By 1½ hr after the injection, a distinct alteration occurred in the nucleoli which was characterized by the appearance of electron-opaque masses in the nucleolonema. After 6–8 hr, the nucleoli showed partial fragmentation into small, dense masses. Large aggregates of interchromatinic granules appeared in the nucleoplasm. Condensation of chromatin became prominent in the nucleoplasm particularly along the nuclear membrane. By 12 hr almost complete fragmentation of nucleoli had occurred. The administration of adenine or methionine at 4 hr prevented the development of nucleolar changes. Also, adenine administration at 8 hr after ethionine completely reversed the nucleolar lesion by 12 hr. After methionine administration at 8 hr, many nucleoli showed incomplete reconstruction with many twisted ropelike structures when viewed 4 hr later. Identical structures were found when adenine was given at 8 hr, and animals were sacrificed 2 hr later. On the basis of this observation, the simplified structures of nucleoli found 2 hr after adenine or 4 hr after methionine appeared to be precursors of the nucleolonema. It is suggested that nucleoli show at least two basic reaction patterns to inhibitors of RNA synthesis, one typified by actinomycin D and one by ethionine.
Whisker stimulation-dependent translation of FMRP in the barrel cortex requires activation of type I metabotropic glutamate receptors

Fragile X syndrome is a common inherited cause of mental retardation that results from the absence of the Fragile X Mental Retardation Protein (FMRP), an RNA binding protein thought to regulate translation of bound mRNAs, including its own. Previous studies in our laboratory have shown that FMRP expression increases in the barrel cortex of the rat after unilateral whisker stimulation, a model of experience dependent plasticity. This increase in protein is restricted to sub-cellular fractions enriched for synaptic or poly-ribosomal complexes. Here, we demonstrate that these increases are not accompanied by a change in FMR-1 mRNA levels and that they are blocked by the protein synthesis inhibitor cycloheximide in a dose dependent manner. Whisker stimulation dependent expression of FMRP is also abolished by pharmacological blockade of either NMDA receptors (MK-801, 0.25 mg/kg) or type I metabotropic glutamate receptors (AIDA, 5 mg/kg). In primary cortical neurons, activation of type I mGluRs leads to an increase in FMRP expression that is not effected by blockade of NMDA receptors. Taken together, these studies show that experience regulates FMRP production in vivo at the level of translation and supports a role for FMRP in metabotropic glutamate receptor mediated synaptic plasticity.
Nonlinear robust control design without requiring any priori information on the control sign

This paper present a robust control scheme for a second order nonlinear system that have not only additive nonlinear uncertainties but also unknown multiplicative signs. These signs are called control directions since they represent effectively the direction of motion under any given control. Except for the unknown control directions, the second order system satisfies the generalised matching conditions (GMC). The GMC design is also called back-stepping because the control is designed by working backwards through two integrators. The design procedure can be generalized and applied to nonlinear systems because it basically forms a sequence of state transformations or sometimes referred to are a recursive design. The proposed robust control is continuous and guarantees global stability of uniform ultimate boundedness without a priori knowledge of the control directions nor the knowledge of nonlinear dynamics except their size bounding functions. This is achieved by online identifying control directions and by utilizing transition laws that change smoothly and accordingly the signs of robust controls. The analysis and design is done using Lyapunov direct method.
The distribution of sympathetic nerve fibers to the hind limb of the cat

In six cats the trunks of the third or fourth lumbar to the third sacral nerves were cut between the dorsal root ganglion and the gray ramus. Studies were made of serial sections of the nerve trunks with their intact gray rami, sections of the peripheral nerves, including most of the motor and sensory nerves of the posterior limb, and serial sections of the blood vessels. The latter were cut into segments and the serial sections made of each segment. IN addition, similar studies of a large number of normal vessels were made.
Properties of the polyoma virus transcription complex obtained from mouse nuclei.

Abstract At a late stage of polyoma virus development in cultures of mouse 3T3 Balb/C, most of the replicated viral DNA which can be solubilized by the SDS method (1) can also be extracted as a 55S DNA-protein complex (2) by the Triton method. However, the Triton pellet fraction obtained from nuclei of infected cells was at least 50 times more active in the synthesis of polyoma-specific RNA than was the Triton supernatant upon addition of nucleoside triphosphates. This finding suggests that the active template for polyoma RNA synthesis in vivo is not the polyoma 55S complex, but rather a minor fraction of the viral DNA which is not solubilized by the Triton method. The in vitro synthesis of polyoma-specific RNA was totally sensitive to inhibition by α-amanitin. Unlike E. coli RNA polymerase, the mouse RNA polymerases were found to be resistant to inactivation by Sarkosyl.
Darwin's selection within the human body

It has been widely accepted that Darwin's natural selection plays a basic role in carcinogenesis and some other disease processes, but is not relevant to the normal multicellular life within the human body. The hypothesis proposed here is that selection and other evolutionary mechanisms not only normally or physiologically exist within the body of human beings and other multicellular organisms, but also persist and 'function' throughout the entire life span of the organism, from the embryo development to the aging process. This is based on the concept of cell individuality and the fact that there are a great deal of variations in cell populations, in particular possible existence of somatic genetic variations within the body. To realize the existence of natural selection in the multicellular life and study how it operates within organisms in both physiological and pathological conditions are fundamentally important to our understanding of human biology and medicine.
Plasmodium falciparum phosphoethanolamine methyltransferase is essential for malaria transmission

Efficient transmission of Plasmodium species between humans and Anopheles mosquitoes is a major contributor to the global burden of malaria. Gametocytogenesis, the process by which parasites switch from asexual replication within human erythrocytes to produce male and female gametocytes, is a critical step in malaria transmission and Plasmodium genetic diversity. Nothing is known about the pathways that regulate gametocytogenesis and only few of the current drugs that inhibit asexual replication are also capable of inhibiting gametocyte development and blocking malaria transmission. Here we provide genetic and pharmacological evidence indicating that the pathway for synthesis of phosphatidylcholine in Plasmodium falciparum membranes from host serine is essential for parasite gametocytogenesis and malaria transmission. Parasites lacking the phosphoethanolamine N-methyltransferase enzyme, which catalyzes the limiting step in this pathway, are severely altered in gametocyte development, are incapable of producing mature-stage gametocytes, and are not transmitted to mosquitoes. Chemical screening identified 11 inhibitors of phosphoethanolamine N-methyltransferase that block parasite intraerythrocytic asexual replication and gametocyte differentiation in the low micromolar range. Kinetic studies in vitro as well as functional complementation assays and lipid metabolic analyses in vivo on the most promising inhibitor NSC-158011 further demonstrated the specificity of inhibition. These studies set the stage for further optimization of NSC-158011 for development of a class of dual activity antimalarials to block both intraerythrocytic asexual replication and gametocytogenesis.
Comparison of the geometric and molecular orbital structures of (Cp*Cr)2B4H8 and (Cp*Re)2B4H8, Cp*=η5-C5Me5. Structural consequences of delocalized electronic unsaturation in a metallaborane cluster

Abstract Comparison of the structures of two metallaboranes possessing the same borane fragment and ancillary metal ligands but differing transition metal atoms defines the geometric consequences of the addition (or removal) of two valence electrons from a bicapped tetrahedral metallaborane cluster structure. Likewise the effects of the cluster distortion on electronic structure is explored utilizing approximate molecular orbital calculations on hypothetical (CpMn) 2 B 4 H 8 , Cp=η 5 -C 5 H 5 , as it is changed from the shape characteristic of five skeletal electron pair (sep) (Cp*Cr) 2 B 4 H 8 to that of six sep (Cp*Re) 2 B 4 H 8 , Cp=η 5 -C 5 Me 5 . In doing so it is demonstrated that the observed changes in the metal–metal distance (a counter-intuitive increase with smaller sep) and endohydrogen positions (more like BH with smaller sep) are required to electronically accommodate the removal of a pair of electrons from a saturated bicapped tetrahedral cluster.
The walk-through approach to authoring multimedia documents

This paper describes a novel approach to authoring multimedia documents based on the walk-through paradigm. Using this approach, multimedia authoring tasks can be performed in the context of the multimedia presentation under construction. It greatly simplifies the authoring process by hiding the use of composition constructs and eliminating the turn-around time from the editing and testing parts of the development cycle. End user multimedia authoring and fast prototyping can therefore be realized.
Results from a Survey of Gravitational Microlensing towards M31

We describe the results of a search for microlensing events affecting stars in the outer bulge and inner disk of M31, due both to masses in M31 and the Galaxy. These observations, from 1994 and 1995 on the Vatican Advanced Technology Telescope and KPNO 4m, are sufficient to rule out masses in the range of ~0.003 M_sol to 0.08 M_sol as the primary consistuents of the mass of M31 towards this field. Furthermore we find six candidate events consistent with microlensing due to masses of about 1 M_sol, but we suspect that some of these may be cases where long-period red supergiant variables may be mistaken for microlensing events. Coverage from anticipated data should be helpful in determining if these sources maintain a constant baseline, and therefore are best described by microlensing events.
Conservatism, preservationism, conservationism and mentalism

According to one way of interpreting Conservatism, there is an asymmetry in the process of belief revision: reasons are needed to give up a belief, but no reason is needed to retain it. So, according to Conservatism, if a subject has no reasons for or against a belief, retaining that belief will be rational, and giving it up will be irrational. There is a kind of case that is of special interest in evaluating Conservatism: scenarios where the subject doesn’t remember how the belief was acquired – many philosophers call these cases of ‘forgotten evidence’. We can distinguish two different kinds of case of forgotten evidence: ‘good’ forgotten evidence cases, where the belief was initially acquired in a rational way, and ‘bad’ forgotten evidence cases, where the belief was initially acquired in an irrational way. Conservatism treats these two cases alike: if the subject hasn’t acquired or retained any defeater for the belief, he is rational in retaining that belief. There is another epistemological view that does distinguish between good and bad cases of forgotten evidence (see Burge 1993, 1997):