cssi/SciSciGPT-SciSciNet huggingface dataset:
Change versus decline: The suburbanization of jobs in U.S. shrinking cities

Abstract Spatial mismatch theory hypothesizes that as jobs suburbanize, minorities and low-income households will disproportionately lose access to economic opportunity. This paper hypothesizes that the context of urban decline also challenges job accessibility. In shrinking cities, growth at the urban fringe not only expands the footprint of the region's urbanized area, but unlike in most strong market settings, it simultaneously hollows out the core, challenging job accessibility for residents. This paper tests this hypothesis by presenting a block-group level model of job accessibility in the Principal Cities of 349 Metropolitan Statistical Areas (MSAs). The model finds that the context of urban decline reduces job accessibility for residents by 6.9%, other things equal. Descriptive statistics are employed to analyze spatial changes in job location over time. The results suggest that as development pushes outward in strong market settings, the core shares in the growth, while in shrinking cities, spatial deconcentration disproportionately weakens the core. This process is hypothesized to lead to the decreased job accessibility found in shrinking cities.
Making Sense of Persistence in Scientific Purgatory: A Multi-Institutional Analysis of Instructors in Introductory Science, Technology, Engineering, and Mathematics (STEM) Courses

Prior research points to a variety of factors that influence student persistence in science, technology, engineering, and mathematics (STEM) degree programs. Little attention, however, has been giv...
Regulation of Iron Storage by CsrA Supports Exponential Growth of Escherichia coli.

ABSTRACT The global regulatory protein CsrA coordinates gene expression in response to physiological cues reflecting cellular stress and nutrition. CsrA binding to the 5′ segments of mRNA targets affects their translation, RNA stability, and/or transcript elongation. Recent studies identified probable mRNA targets of CsrA that are involved in iron uptake and storage in Escherichia coli, suggesting an unexplored role for CsrA in regulating iron homeostasis. Here, we assessed the impact of CsrA on iron-related gene expression, cellular iron, and growth under various iron levels. We investigated five new targets of CsrA regulation, including the genes for 4 ferritin or ferritin-like iron storage proteins (ISPs) and the stress-inducible Fe-S repair protein, SufA. CsrA bound with high affinity and specificity to ftnB, bfr, and dps mRNAs and inhibited their translation, while it modestly activated ftnA expression. Furthermore, CsrA was found to regulate cellular iron levels and support growth by repressing the expression of genes for ISPs, most importantly, ferritin B (FtnB) and bacterioferritin (Bfr). Iron starvation did not substantially affect cellular levels of CsrA or its small RNA (sRNA) antagonists, CsrB and CsrC. csrA disruption led to increased resistance to the lethal effects of H2O2 during exponential growth, consistent with a regulatory role in oxidative stress resistance. We propose that during exponential growth and under minimal stress, CsrA represses the deleterious expression of the ISPs that function under oxidative stress and stationary-phase conditions (FtnB, Bfr, and Dps), thus ensuring that cellular iron is available to processes that are required for growth. IMPORTANCE Iron is an essential micronutrient for nearly all living organisms but is toxic in excess. Consequently, the maintenance of iron homeostasis is a critical biological process, and the genes involved in this function are tightly regulated. Here, we explored a new role for the bacterial RNA binding protein CsrA in the regulation of iron homeostasis. CsrA was shown to be a key regulator of iron storage genes in Escherichia coli, with consequential effects on cellular iron levels and growth. Our findings establish a model in which robust CsrA activity during the exponential phase of growth leads to repression of genes whose products sequester iron or divert it to unnecessary stress response processes. In so doing, CsrA supports E. coli growth under iron-limiting laboratory conditions and may promote fitness in the competitive iron-limited environment of the host large intestine.
Metal Chelating Polymer Thin Films by Surface-Initiated ROMP and Modification

We report the surface-initiated ring-opening metathesis polymerization (SiROMP) of hydroxamic acid-containing, metal-chelating polymer thin films. SiROMP of trans-5-norbornene-2,3-dicarbonyl chloride (NBDAC) is introduced as a versatile platform to achieve many functional polymer films via simple exposure of pNBDAC films to reagents. This modification strategy owes its success to the fast and high-yield reaction of acyl chlorides with alcohols, amines, water, and other molecules. The polymerization of NBDAC is performed with monomer in the vapor phase and exhibits rapid kinetics, producing ∼400 nm thick films within 5 min. Because of the high reactivity of the acyl chloride groups in the film, the pNBDAC films are easily modified to produce side chains of carboxylic acids, esters, and amides via the reaction of the acyl group with water, alcohols, and amines, respectively. Exposure of the pNBDAC film to hydroxylamine results in a film with hydroxamic acid functionality that is capable of chelating various...
Prediction machines: the simple economics of artificial intelligence: by Ajay Agrawal, Joshua Gans and Avi Goldfarb, Published in 2018 by Harvard Business Review Press, 272 pp., $30.00 (hardcover), Kindle Edition: $16.19, ISBN:978-1-633695672

Our first key insight is that the new wave of artificial intelligence does not actually bring us intelligence but instead a critical component of intelligence – prediction. – Ajay Agrawal, Joshua G...
Illness Understanding, Prognostic Awareness, and End-of-Life Care in Patients With GI Cancer and Malignant Bowel Obstruction With Drainage Percutaneous Endoscopic Gastrostomy.

PURPOSE:Malignant bowel obstruction (MBO) is common in advanced GI cancer, and MBO management, including drainage percutaneous endoscopic gastrostomy (dPEG), is palliative. How patients understand ...
The Impact of Erythropoietin on Short- and Long-Term Kidney-Related Outcomes in Neonates of Extremely Low Gestational Age. Results of a Multicenter, Double-Blind, Placebo-Controlled Randomized Clinical Trial

Objective To evaluate whether extremely low gestational age neonates (ELGANs) randomized to erythropoietin have better or worse kidney-related outcomes during hospitalization and at 22-26 months of corrected gestational age (cGA) compared with those randomized to placebo. Study design We performed an ancillary study to a multicenter double-blind, placebo-controlled randomized clinical trial of erythropoietin in ELGANs. Results The prevalence of severe (stage 2 or 3) acute kidney injury (AKI) was 18.2%. We did not find a statistically significant difference between those randomized to erythropoietin vs placebo for in-hospital primary (severe AKI) or secondary outcomes (any AKI and serum creatinine/cystatin C values at days 0, 7, 9, and 14). At 22-26 months of cGA, 16% of the cohort had an estimated glomerular filtration rate (eGFR) 30 mg/g, 23% had a systolic blood pressure (SBP) >95th percentile for age, and 40% had a diastolic blood pressure (DBP) >95th percentile for age. SBP >90th percentile occurred less often among recipients of erythropoietin (P 95th percentile, or DBP >90th or >95th percentiles at the 2 year follow-up visit. Conclusions ELGANs have high rates of in-hospital AKI and kidney-related problems at 22-26 months of cGA. Recombinant erythropoietin may protect ELGANs against long-term elevated SBP but does not appear to protect from AKI, low eGFR, albuminuria, or elevated DBP at 22-26 months of cGA.
Repurposing of Metformin for Cancer Therapy: Updated Patent and Literature Review.

Background Over recent years, there has been an increasing focus on the repurposing of existing, well-known medications for new, novel usage. One such drug is metformin, typically utilized in the management of diabetes, which demonstrates a positive relationship between its administration and lower cancer morbidity and mortality. Based on this finding, numerous studies and clinical trials have been conducted to examine the potential usage of metformin as an anticancer agent. Objective This article aims to summarize metformin's anticancer effects through reviewing its literature and patents, with a focus on its potential to be repurposed for cancer therapy. Methods Various databases were examined using keywords, 'Metformin' and 'Cancer'. Research articles were collected through the PubMed database, clinical trials were obtained from the Clinical Trials database, and patents were collected through the Google Patents database. Results Metformin shows antineoplastic activity in various models. These anticancer properties appear to synergize with existing chemotherapeutics, which allows for a reduction in drug dosage without losing potency while minimizing adverse effects. Numerous patents on metformin have been filed which claim various combination therapies, delivery methods, and uses for cancer therapy, displaying an increasing interest in metformin's anticancer potential. Conclusion Preclinical studies, along with early phase clinical trials, have examined antitumor properties of metformin on a variety of cancers. Metformin's anticancer effects are well documented, demonstrating a great promise in improving current cancer therapies. However, there is a significant lack of late phase clinical trials, specifically those involving non-diabetic cancer patients, and therefore further research in this area is required.
Language Tasks and the Network Control Role of the Left Inferior Frontal Gyrus

Recent work has combined cognitive neuroscience and control theory to make predictions about cognitive control functions. Here, we test a link between whole-brain theories of semantics and the role of the left inferior frontal gyrus (LIFG) in controlled language performance using network control theory (NCT), a branch of systems engineering. Specifically, we examined whether two properties of node controllability, boundary and modal controllability, were linked to semantic selection and retrieval on sentence completion and verb generation tasks. We tested whether the controllability of the left IFG moderated language selection and retrieval costs and the effects of continuous θ burst stimulation (cTBS), an inhibitory form of transcranial magnetic stimulation (TMS) on behavior in 41 human subjects (25 active, 16 sham). We predicted that boundary controllability, a measure of the theoretical ability of a node to integrate and segregate brain networks, would be linked to word selection in the contextually-rich sentence completion task. In contrast, we expected that modal controllability, a measure of the theoretical ability of a node to drive the brain into specifically hard-to-reach states, would be linked to retrieval on the low-context verb generation task. Boundary controllability was linked to selection and to the ability of TMS to reduce response latencies on the sentence completion task. In contrast, modal controllability was not linked to performance on the tasks or TMS effects. Overall, our results suggest a link between the network integrating role of the LIFG and selection and the overall semantic demands of sentence completion.
Do Economic Conditions Affect Climate Change Beliefs and Support for Climate Action? Evidence from the U.S. in the Wake of the Great Recession

I show that climate skepticism increases with negative economic shocks and that effects are concentrated among individuals in the labor force. I primarily employ a panel of US individuals in the period following the Great Recession, but also find consistent results with an alternative instrumental variables strategy. Among labor force participants, a one percentage point increase in the local unemployment rate leads to a 3 to 5 percentage point decrease in the probability of believing climate change is real and requires action. I conclude that support for climate change policies could depend on labor market conditions.
Functionalized metallic carbon nanotube arrays for gas phase explosives detection

Abstract Gas phase detection of explosive molecules is a sensing application of wide interest. Light weight, low power sensors are needed for mobility and wide dissemination, however low vapor pressures and the presence of similar functional groups in a variety of explosive molecules make the development of sensitive and selective detection systems difficult. Experimental research has reported some success in the development of carbon nanotube (CNT) based explosives sensors, however safety considerations and strict controls on the distribution of explosive materials hamper experimental progress. Ab initio modeling of functionalized carbon nanotubes suggests that chemiresistive sensor arrays employing hydroxyl, carboxylic acid, oxygen, and amine groups can distinguish common background gases from both nitroaromatic and nitramine explosives, distinguish between nitroaromatic and nitramine explosives, and distinuguish similar nitramine explosives from each other. The modeling results on functionalized CNT sensing arrays suggest that they offer important opportunities for future experimental research.
TRANSPORTATION TAXATION POLICIES FOR VIRGINIA

Improving the revenue base of the Virginia Division of Motor Vehicles by means of changes in the transportation tax system is explored. An econometric forecasting model was developed to project the potential revenues from Virginia’s motor fuel sales tax, vehicle sales and use tax, and registration fee system. Among the options explored are: increases in the tax per gallon of motor fuel, a fuel sales tax indexed to gasoline prices, an ad valorum fuel tax, in addition to the current tax per gallon, increases in addition to the current tax per gallon, increases in the percent vehicle sales and use tax, and increases in registration fees. Although each scheme had its advantages and disadvantages, it was found that the most productive and least politically awkward way of stabilizing the Division of Motor Vehicle revenue base is probably an increase in the vehicle sales and use tax.
Nonrepeating FSK and interference mitigation for high data-rate frequency hop communication systems

The mitigation of intersymbol interference in high data-rate frequency-hop communication systems is impeded by the fact that the effects of the channel can change significantly with each hop. The paper investigates novel techniques for mitigating interference without the use of an equalizer. A nonrepeating form of frequency shift keying is proposed along with an interference mitigation algorithm that is specifically designed for use with this modulation. The algorithms are low in complexity and effectively mitigate interference spanning multiple adjacent symbols.
Gas-Forming Pyogenic Liver Abscess with Septic Shock

The pyogenic liver abscess caused by Clostridium perfringens (C. perfringens) is a rare but rapidly fatal infection. The main virulence factor of this pathogen is its α-toxin (lecithinase), which decomposes the phospholipid in cell membranes leading to cell lysis. Once the bacteria are in blood stream, massive intravascular hemolysis occurs. This can present as anemia on admission with evidence of hemolysis as indicated by low serum haptoglobin, high serum lactate dehydrogenase (LDH), elevated indirect bilirubin, and spherocytosis. The clinical course of C. perfringens septicemia is marked by rapidly deteriorating course with a mortality rate ranging from 70 to 100%. The very rapid clinical course makes it difficult to diagnose on time, and most cases are diagnosed at autopsy. Therefore it is important to consider C. perfringens infection in any severely ill patient with fever and evidence of hemolysis. We present a case of seventy-seven-year-old male with septic shock secondary to pyogenic liver abscess with a brief review of existing literature on C. perfringens.
Valved Glaucoma Drainage Devices in Pediatric Glaucoma: Retrospective Long-term Outcomes.

Importance Relatively little data exist about the long-term outcomes of an initial glaucoma drainage device (GDD) and subsequent GDDs implanted in pediatric patients with glaucoma. Objective To determine the long-term outcomes of the first and second GDDs and risk factors in pediatric glaucoma. Design, Setting, and Participants Retrospective review of 119 eyes of 89 patients younger than 18 years with glaucoma who underwent valved GDD implantation from March 1999 to April 2012 at the Stein Eye Institute, University of California, Los Angeles. Exposure Implantation of GDD, using silicone and polypropylene Ahmed glaucoma valve. Main Outcomes and Measures Kaplan-Meier survival analysis and risk factors associated with GDD failure. Success was defined as a final intraocular pressure of 5 to 21 mm Hg as well as a 20% reduction from baseline intraocular pressure with or without medications. Results The mean (SD) age at implantation of the first GDD was 6.8 (5.7) years. The mean (SD) follow-up time was 6.1 (3.3) years from surgery. The mean intraocular pressure was reduced by 13.0 mm Hg (95% CI, 8.8 to 17.3 mm Hg) at 5 years postoperatively. The mean number of glaucoma medications preoperatively vs postoperatively was not different starting at 5 years (reduction of 0.5; 95% CI, −0.1 to 1.0). The success rate at 5 years was 55.0% (95% CI, 46.0% to 65.9%). Risk factor analysis suggests that older age (risk ratio = 0.95; 95% CI, 0.90 to 0.99; P = .02), uveitic glaucoma (risk ratio = 0.34; 95% CI, 0.14 to 0.86; P = .02), and polypropylene GDDs (risk ratio = 0.39; 95% CI, 0.23 to 0.67; P = .001) were associated with higher success rates. Thirty-six eyes received a second GDD, with a mean (SD) of 2.2 (1.6) years between the 2 operations. The success rate 5 years after the second surgery was 52.8% (95% CI, 37.0% to 75.3%). Risk factors associated with failure of the first GDD were not found to affect the likelihood of failure for the second. Conclusions and Relevance Glaucoma drainage devices, such as the Ahmed glaucoma valve, have moderate long-term success rates in pediatric patients with glaucoma. In pediatric patients, the first GDD is successful in 46% to 70% of patients at 5 years with medications, and the second GDD is successful in 37% to 75% of patients at 5 years after the subsequent surgery.
In Vivo Conversion of the Single-Stranded DNA of the Kilham Rat Virus to a Double-Stranded Form

Abstract Kilham rat virus (KRV) contains linear, single-stranded DNA in the virion. The fate of radioactive viral DNA was followed after infection of monolayer cells. Within 60 min after infection of cells, 28 to 42% of the parental viral DNA is converted to a new form. This new DNA form is believed to be double stranded and linear on the basis of its sedimentation in neutral and alkaline sucrose gradients, elution from hydroxyapatite columns, its buoyant density in equilibrium CsCl density gradients, and appearance in the electron microscope. The double-stranded linear KRV DNA may be analogous to the replicative form of certain bacteriophages, including X174, which contain single-stranded circular genomes.
Optimization of Liquid Desiccant Systems for Solar/Geothermal Dehumidification and Cooling

Two efficient design configurations of a liquid desiccant cooling/dehumidification system that can be powered by low grade solar or geothermal energy and promise low parasitic power requirements for blowers and pumps are proposed and analyzed in this work. A mathematical model for each component in this system has been developed and synthesized for system simulation. The system performance is predicted and optimized through parametric studies using the computer code LIQSYS. It is shown that the exhaust recirculation mode (ERM) gives better performance at full capacity while the process recirculation mode (PRM) produces cooler and drier air.
Solubilization of ferrihydrite iron by plant phenolics: A model for rhizosphere processes

Abstract Several naturally‐occurring phenols, including some which are exuded by iron deficient roots, promote the reduction and release of ferrihydrite iron. The initial rate of iron reduction brought about by each phenol was determined by spectrophotometric measurement of the Fe(ferrozine)2 3 + complex which absorbs maximally at 562 nm. The rate of iron release was dependent upon the concentration of phenol and ferrihydrite, but not on the concentration of added ferrozine. The order of reactivity was: caffeic acid > chlorogenic acid > ferulic acid > p‐coumaric acid. A direct correlation was observed between the reducing ability for each phenol and its ability to release ferrihydrite iron. The optimum pH range was 5.0–6.0. Cu(II) and Ni(II) inhibited the reduction of ferrihydrite iron by the phenols. This study introduces a model for the investigation of chemical processes occurring at the soil‐root interface.
Reconstruction of tissue dynamics in the compressed breast using multiplexed measurements and temporal basis functions

In the course of our experiments imaging the compressed breast in conjunction with digital tomosynthesis, we have noted that significant changes in tissue optical properties, on the order of 5%, occur during our imaging protocol. These changes seem to consistent with changes both in total Hemoglobin concentration as well as in oxygen saturation, as was the case for our standalone breast compression study, which made use of reflectance measurements. Simulation experiments show the importance of taking into account the temporal dynamics in the image reconstruction, and demonstrate the possibility of imaging the spatio-temporal dynamics of oxygen saturation and total Hemoglobin in the breast. In the image reconstruction, we make use of spatio-temporal basis functions, specifically a voxel basis for spatial imaging, and a cubic spline basis in time, and we reconstruct the spatio-temporal images using the entire data set simultaneously, making use of both absolute and relative measurements in the cost function. We have modified the sequence of sources used in our imaging acquisition protocol to improve our temporal resolution, and preliminary results are shown for normal subjects.
Aspartate aminotransferases from ribbed mussel gill tissue: Reactivity with β-l-cysteinesulfinic acid and other properties

Abstract 1. 1. The β-form of the cytosolic aspartate aminotransferase (cAAT) and the mitochondrial aspartate aminotransferase (mAAT) from ribbed mussel ( Modiolus demissus = Gukensia demissa ) gill tissue each exist as dimers of equal mol. wt (44,000). 2. 2. Both the cAAT and mAAT are reactive with β- l -cysteine sulfinic acid (CSA) as an amino donor substrate. 3. 3. The apparent K m s for CSA are very high (19–250 mM) and increase with decreasing pH.
Progress in Ignition Experiments at the NIF

at 80-90% of the ignition point design values. This paper will discuss the experiments and plans to understand and resolve the underlying physics issues.
Espirit de Corps Among Army Corps of Engineer Executives: Job Satisfaction and Espirit after Ten Years of the SES — Some Unexpected Findings

A major focal point in discussions of how the federal bureaucracy might best be improvedrelates to the job satisfaction of its senior managers. Their performance, it has been broadly assumed, will strongly influence the overall performance of governmental organizations. If theyperform in an exemplary manner their example and competence will stimulate their subordinates to do likewise. This study investigates this important area of public personnel managementby looking at the results of the implementation of the Senior Executive Service in the U.S. Army Corps of Engineers ten years after its creation in the Civil Service Reform Act of 1978.
Modeling protected species as an undesirable output: the case of sea turtle interactions in Hawaii's longline fishery.

Abstract Interactions with sea turtles have occurred at an alarming rate in swordfish longlining in Hawaii in recent years and various regulations have been put forward to protect sea turtles. In order to understand the cost of reducing sea turtle interactions, methods have been developed to derive the shadow price of sea turtle bycatch based on fisher's welfare loss from a specific regulation. This paper illustrates an alternative method of calculating temporal and trip-specific cost of sea turtle bycatch reduction. The advantages of this method lie in the computation of shadow price without assuming specific regulation implementation and its relatively modest data requirement. A parametric output distance function is used to simultaneously model desirable and undesirable catches. Using the duality argument, the revenue-related shadow price of sea turtle bycatch can be derived from the estimated distance function. Average shadow price of sea turtle bycatch for the period 1991–1999 is estimated to be US $30 873 in 1991 dollars. Average shadow prices of sea turtle bycatch by trip characteristics, such as fishing year, trip type and location are also estimated. Such information can be useful for policy makers to analyze tradeoffs and make appropriate policy decisions.
Mobilizing social pressures toward small families.

(1966). Mobilizing social pressures toward small families. Eugenics Quarterly: Vol. 13, No. 2, pp. 122-127.
An additional source of error in microsphere measurement of regional blood flow.

The effects of variations in rate of microsphere injection and site and rate of reference sample withdrawal were studied to further define sources of error in microsphere measurements of regional blood flow. Anesthetized canines underwent sequential left ventricular injection of radiolabeled 25-μm microspheres at slow and fast injection speeds. Simultaneous reference samples were collected from brachial and femoral artieres at slow (5 ml/min) and fast (13 ml/min) withdrawal rates. Calculated renal blood flows (RBF) were compared for each injection rate, sampling site, and withdrawal rate. Varying injection rate or withdrawal site resulted in no significant differences in RBF. RBF was influenced significantly (P < 0.005) by reference sample withdrawal (fast withdrawal 4.38 ± 1.28 ml/min·g vs slow withdrawal rate 6.87 ± 2.29 ml/min·g). Data indicate that selection of an inappropriately slow rate of reference sample withdrawal results in erroneous values of regional blood flow.
A simplified technique for recording an implant-supported ovate pontic site in the esthetic zone

Implant-supported fixed dental prostheses present an esthetic challenge, especially when an ovate pontic site has been progressively developed during the guided soft-tissue healing process with an interim restoration. This article describes a technique for an accurate capturing of the molded ovate pontic site of an implant-supported fixed dental prostheses and for transferring it to the definitive cast, which facilitates the dental ceramist's ability to design and fabricate an ovate pontic with adequate intaglio contours.
Preliminary Orbit Determination of a Tethered Satellite Using the f and g Series

A renewed interest in the deployment of tethered satellites has led to a need for a preliminary orbit determination method which is capable of distinguishing tethered satellites from untethered ones. Several of the classical preliminary orbit determination methods, which are used for Keplerian satellites, generally require two or more position vectors along with their respective observation times in order to determine a preliminary orbital element set. These conventional methods, however, are unable to distinguish between Keplerian and tethered satellites, whose motion is modified due to the presence of a tether force. The use of these conventional methods will result in the calculation of inaccurate orbital elements if the observed satellite is part of a tethered satellite system. Modifications have been made to the f and g series preliminary orbit determination method in order to allow for the identification of tethered satellites. These modifications allow for the calculation of a gravitational parameter, in addition to a set of orbital elements, which can be used to distinguish between a tethered satellite and an untethered one. This paper applies this modified f and g series method to the problem of the quick identification of a tethered satellite. The performance of this method is evaluated through scenarios of differing tether lengths, levels of observation error, and orbital eccentricities. Due to the desire for the preliminary orbit determination to be achieved quickly, only short time intervals between observations were considered. A description of how this preliminary orbit information can be used to obtain tether parameters for the subsequent differential correction process is also provided.
On the Use and Interpretation of Logical Symbols

The term ‘symbol’ is a relative term: for anything to be a symbol, it must have a reference. It is a symbol only by virtue of standing for something, or being a surrogate, often for a stimulus not present. The words of natural language are symbols the reference of most of which goes back in the last analysis to factors in conscious experience. Such reference is not precise, and since it is desirable that logical symbolism be precise, logic has come to be elaborated in artificial languages the symbols of which do not depend on reference to experience. The symbols of a strict logical system should not depend on any reference they have outside the systematic structure.
Comparison of Various In Vitro Methods for the Determination of Limestone Solubility

Abstract A technique for measuring limestone solubility in vitro was developed. Nine limestone sources each screened to four different sizes (average United States screen number = 6, 15, 35, and 100, respectively) were used for the assays. Solubility was reported as the percentage weight loss of the limestone sample during the 10-min in vitro assay. A similar experiment was conducted to obtain both the values of pH changes and the number of moles of proton consumed during the 10-min reaction. The model for predicting solubility (Y) from the pH change (X) was Y = 22.0450 + 5.92771n(X) – 1.24941n(X)2 – .36921n(X)3; the model for predicting solubility from proton consumption (Z) was Y = .5563 + 302.8400 Z. The model for percentage of hydrogen ion disappearance involved a Degree 4 polynomial equation and was not used to predict solubility. When the particle size within each source decreased, the newly developed percentage of weight loss method showed a more gradual increase in solubility when compared with the method of Rabon and Roland reported in 1985. The two methods for obtaining percentage of weight loss ranked the samples within each source in the same order; however, some discrepancies existed between results of the two methods when ranking was done with samples from different sources. The relationship between solubility and size was not linear but involved a Degree 4 polynomial equation. The pH plateau time method had relatively less predictive power of solubility.
Hypothesis: warfarin administered simultaneously with heparin infusion will prevent heparin-discontinuance associated coronary thrombosis

Recent studies have evidenced an association between the time of heparin discontinuance and coronary artery reocclusion. Some investigators have concluded that inadequate heparinization was responsible, and further heparin infusion or an increase in dose would have been indicated. However, several investigators (Rao: Thrombosis Research 24:181-186, 1981; Marciniak and Gockerman: Lancet September 17:581-584, 1977; Fisken et al.: Lancet December 10: 1231, 1977; Conard et al.: Thrombosis Research 22:507-511, 1981; Kakkar et al.: Lancet January 12:103-104; Green: Lancet February 16:374, 375; Harborne and Nicolaides: Thrombosis Research 43:657-662, 1986; Bonen et al.: Thrombosis Research 27:123-124, 1982; Blomback et al.: Acta Physiologica Scandinavica 58:306-318, 1963; Holm et al.: Scandinavian Journal of Haematology 35:564-569, 1985; Andersson et al.: Thrombosis Research 34:333-340, 1984) have demonstrated that antithrombin III levels are reduced in patients on intravenous heparin. Both reduced antithrombin III levels and reduced rate of antithrombin inhibition of thrombin at the time of heparin discontinuance may increase the risk of coronary rethrombosis. If this theory is correct, increasing heparin infusion may exacerbate this risk. We propose an investigation that will provide evidence for or against the decreased antithrombin III theory, and in doing so, test an experimental therapy designed to prevent coronary reocclusion upon heparin discontinuance. In a randomized, placebo-controlled double-blinded study, we will determine whether simultaneous administration of warfarin with heparin initiation provides more time to increase antithrombin III levels and prevent coronary reocclusion upon heparin discontinuance, compared to heparin without warfarin therapy.
Achromatic contrast effects in infants: Adults and 4-month-old infants show similar deviations from Wallach’s ratio rule

When adults view a disk of light embedded in a higher luminance surround, the perceived lightness of the disk is largely determined by the surround to disk luminance ratio (Wallach's ratio rule). In the present study, both adult and infant subjects were tested with multiple discrete trial procedures in which the surround luminance was decreased between the study and test phases of each trial. Tested with sequential lightness matching, adult subjects showed an approximate ratio rule, with a small but consistent deviation in the direction of a luminance match. Tested with a forced-choice novelty preference technique in combination with a cross-familiarization paradigm, 4-month-old infants showed preference minima that fell closer to the mean adult match than to the ratio rule. This finding suggests that, at least for a relatively simple visual display, 4-month-old infants' looking preferences are governed by an adult-like achromatic contrast system.
Alternate Solutions to Multivariate models

Stepwise discriminant function analysis and univariate analysis were carried out on 48 skeletal samples of males from Mediterranean Europe and the Midele East, ranging in time from 3100 b.c. to 200 a.d. The samples were sorted in nine, seven and two group models, according to a consideration of varying units of genetic space as well as archaeological, historical and linguistic considerations. Genetic space can be defined heuristically as the unit of area containing populations in a space/time continuum which are statistically significantly different from other such units. Multivariate analysis allows the rejection of the null hypothesis, that the samples cannot be divided into nine, seven and two group models. Univariate analysis allows the rejection of the null hypothesis only for the nine group model. A model of population similarity by time rather than space is tested; the null hypothesis here cannot be rejected by both multivariate and univariate techniques. It is concluded that univariate analysis is more effective than multivariate analysis in determining the nature and extent of population evolution in this region.
Multiparameter quantum enveloping algebras

Let A = A(p, λ) be the multiparameter deformation of the coordinate algebra of n × n matrices as described by Artin, et al. (1991). Let U be the quantum enveloping algebra which is associated to A, in the sense of Faddeev, Reshetikhin and Takhtadzhyan. We prove a PBW theorem for U and establish a presentation by generators and relations, when λ is not a root of unity. Our approach depends on a cocycle twisting method which reduces many arguments to the standard one-parameter deformation.
Effect of maternal height and weight on risk for preterm singleton and twin births resulting from IVF in the United States, 2008-2010.

Objective To analyze the effects of preconception maternal height and weight on the risk of preterm singleton and twin births resulting from in vitro fertilization (IVF). Study Design We performed a retrospective cohort analysis of the incidence of very early preterm birth (VEPTB), early preterm birth (EPTB), and preterm birth (PTB), before 28, 32, and 37 completed weeks, respectively, in 60,232 singleton and 24,111 twin live births using 2008-2010 live birth outcome data from the Society for Reproductive Technology Clinic Outcome Reporting System. Result Maternal obesity is associated with significantly increased risk of VEPTB, EPTB, and PTB in pregnancies conceived by IVF. For morbidly obese women (body mass index ≥35) with singletons, rates of VEPTB, EPTB, and PTB were 1.7%, 3.6%, and 16.4%, with adjusted risk ratios (aRRs) and 95% confidence levels (CIs) of 2.6 (1.8–3.6), 2.2 (1.8–2.6), and 1.5 (1.4–1.7) using corresponding rates for normal body mass index (95% CI, 18.6–24.9) as referent. For morbidly obese women with twins, rate of VEPTB and EPTB were 6.5% and 12.5%, with aRRs and 95% CIs of 2.4 (1.8–3.0) and 1.5 (1.3–1.8). For singletons, the rate of PTB for short stature women ( Conclusion Preconception maternal obesity and short stature are associated with significantly increased risk of VEPTB and early preterm singleton and twin births in pregnancies resulting from IVF.
A purely hydrodynamic mechanism for atmospheric banding and continental drift

Abstract A periodic rotating gravitational force will produce purely hydrodynamic flow fields on the outside and inside of rotating spheres in the laboratory which are compatible with the observable banded atmospheric structure of Jupiter, Venus, and possibly other planets, and the apparent motions of lithospheric plates on the surface of the earth. Thermal gradients are not required to produce convective flow in this system.
Atom/fragment contribution method for estimating octanol-water partition coefficients

Atom/fragment contribution values, used to estimate the log octanol-water partition coefficient (log P) of organic compounds, have been determined for 130 simple chemical substructures by a multiple linear regression of 1120 compounds with measured log P values. An additional 1231 compounds were used to determine 235 "correction factors" for various substructure orientations. The log P of a compound is estimated by simply summing all atom/fragment contribution values and correction factors occurring in a chemical structure. For the 2351 compound training set, the correlation coefficient (r2) for the estimated vs measured log P values is 0.98 with a standard deviation (SD) of 0.22 and an absolute mean error (ME) of 0.16 log units. This atom/fragment contribution (AFC) method was then tested on a separate validation set of 6055 measured log P values that were not used to derive the methodology and yielded an r2 of 0.943, an SD of 0.408, and an ME of 0.31. The method is able to predict log P within +/- 0.8 log units for over 96% of the experimental dataset of 8406 compounds. Because of the simple atom/fragment methodology, "missing fragments" (a problem encountered in other methods) do not occur in the AFC method. Statistically, it is superior to other comprehensive estimation methods.
Sorption studies of europium(III) on hydrous silica

Sorption behavior of europium, Eu3+, on SiO2 . xH2O (silica gel) has been investigated as a function of time, the amount of silica gel, Eu3+ concentration, the ionic strength, and pH (in absence and in presence of carbonate). The sorption data were fitted to Freundlich, Langmuir and Dubinin-Radushkevich (D-R) isotherms. The sorption capacity of silica gel was determined to be in the range of (2.62-8.00) . 10-7 mol/g at pH 5.30±0.05 and 0.20M NaClO4. The mean energy of sorption was calculated to be 13.50±0.05 kJ/mol from the D-R isotherm, suggesting the involvement of ion-exchange reactions in the sorption process. Sorption of Eu3+ decreased with increased ionic strength. A gradual decrease in pH with increased ionic strength supports the involvement of an ion-exchange mechanism in the sorption process. The diffusion coefficient of Eu3+ ion on silica gel was calculated as (3.98±0.12) . 10-13 m2 . s-1 under the particle diffusion-controlled conditions.
Dependence of mutational asymmetry on gene-expression levels in the human genome.

A great deal of effort has been devoted to measuring the rates of different types of nucleotide substitutions. Mutation rates are known to depend on factors such as methylation status and nearest-neighbor nucleotide effects. However, until recently, in eukaryotes, the rates have not been considered to be strand specific. In a recent analysis of mammalian lineages, Green et al. (2003) uncovered an asymmetry in the frequencies of substitutions on the coding and noncoding strands of genes and showed that this resulted in a nucleotide-content asymmetry within most genes. The authors argue that this bias may be caused by the mammalian transcription-coupled repair in germ cells, but they did not demonstrate an association with germ-cell gene expression. In this work, I analyze nucleotide contents in genes with known expression patterns and levels and provide evidence that the observed asymmetry in mutation rates is, in fact, caused by transcription. The results also imply that germline transcription may occur in a large percentage, 71%–91%, of all human genes.
On update algorithms for quickest paths

The quickest path problem deals with the transmission of a message of size @s from a source to a destination with the minimum end-to-end delay over a network with bandwidth and delay constraints on the links. The path-table that maps all intervals for @s to the corresponding quickest paths can be computed in O(m^2+mnlogn) time, where n and m are the number of nodes and links of the network, respectively. We propose linear-time algorithms that update the path-table after a increase or decrease bandwidth of a link or a path, respectively.
Properties of Concurrent Programs

A program property is a predicate on programs. In this paper we explore program properties for safety, progress and parallel composition, of the form U ? V where U and V are either predicates on states of a program or program properties, and ? satisfies three rules that are also enjoyed by implication. We show how such properties can be used to reason about concurrent programs. Our motivation is to explore methods of reasoning based on a very small number of widely-known rules.
Aerosol deposition in bends with turbulent flow

Numerical and experimental techniques were used to characterize aerosol penetration through bends. Agreement between numerical and physical experiments was achieved when the numerical approach was based on the use of a specially developed three-dimensional particle tracking technique. It is also demonstrated that turbulence needs to be included in a particle tracking model. The effect of flow Reynolds number upon particle deposition was examined numerically. Physical experiments were conducted to investigate the effect of curvature ratio on aerosol penetration. The bends were constructed such that each bend had the same initial and final spatial co-ordinates, regardless of the curvature ratio. The effect of flattening on aerosol penetration was tested by pinching bends at the 45° location, with degrees of flattening from 0% to 50%. Numerical experiments were carried out to characterize the penetration of aerosols through bends. The geometrical extent of the bends covered only the region of tubing where the radius of curvature is finite
Real-Time Monitoring of the Weld Penetration State in Laser Welding of High-Strength Steels by Airborne Acoustic Signal

Nowadays high-strength steels have great applications in different industries due to their good combination of formability, weldability, and high strength-to-weight ratio. To guarantee a high quality without the presence of defects such as partial penetration (PP) in the laser welding of high-strength steels, it is very important to on-line monitor the whole welding process. While optical sensors are widely applied to monitor the laser welding process, we are proposing to use a microphone to acquire the airborne acoustic signals produced during laser welding of high-strength steel DP980. In order to extract valuable information from a very noisy signal acquired in a harsh environment such as industrial welding, spectral subtraction (SS), a noise reduction method is used to process the acquired airborne sound signals. Furthermore, by applying the power spectrum density (PSD) estimation method, the frequency characteristics of the acoustic signals are analyzed as well. The results indicate that the welds in full penetration (FP) and PP produce different signatures of acoustic signals that are characterized with different sound pressure levels and frequency distributions ranging from 500 Hz to 1500 Hz. Based on these differences, two algorithms are developed to distinguish the FP from PP during the laser welding process. A real-time monitoring system is implemented by a LabVIEW-based graphic program developed in this research. A feedback control system that could guarantee the FP will be developed in the near future.Copyright © 2009 by ASME
Pervasive Change Challenges Elders

Is pervasive computing fundamentally incompatible with aging? Our industry designs devices to last for only a couple of years, yet those who struggle with short-term-memory loss find it difficult to adapt to constant changes. At some point, our industry must recognize this specialized need and create a platform with some amount of constancy that can be upgraded to new hardware as necessary. The Web extra offers a list of the reviewers who made IEEE Pervasive Computing's volume 12 possible.
Parent perfectionism and psychopathology symptoms and child perfectionism

Abstract Perfectionism is a multidimensional construct associated with various psychological problems. Studies regarding risk factors for perfectionism are scarce but evidence suggests that parents may be highly involved in their child’s perfectionism. The present study included 160 children aged 8–17 years (67 males, 93 females) and their parents. Relationships between parent and child perfectionism and between parent psychopathology and child perfectionism were examined across 5 age groups (8–9 years, 10–11 years, 12–13 years, 14–15 years, 16–17 years). Self-oriented perfectionism was highest among children aged 16–17 years. Maternal perfectionism and maternal psychopathology predicted child self-oriented and socially prescribed perfectionism. Maternal anxiety mediated the relationship between maternal other-oriented perfectionism and socially prescribed perfectionism in children aged 8–12 years. Maternal perfectionism and psychopathology may constitute risk factors for child perfectionism. Findings are discussed in terms of their implications for theories of perfectionism.
Unsteady homothermal motions of fluids and isotropic solids

Motions of a certain type are shown to be possible in every compressible or incompressible, homogeneous, isotropic simple material, in the absence of body force. These motions have a specific spatial dependence and the nature of the time dependence, for a particular material, is determined by the material response function or functional for the shear stress in simple shear. It is shown further that motions of this type, and spatially homogeneous, time dependent temperatures, can be supported without application of body force or radiative supply of heat.
The Sensitivity of Ribosomal Functions in Tetrahymena pyriformis to Varying Doses and Dose Rates of Gamma-Radiation

exponentially growing cultures of the ciliate protozoan Tetrahymena pyriformis after doses of 0-120 krad of 60Co gamma-radiation delivered at three different dose rates. The polysome content decreases exponentially with increasing dose at all three dose rates. Curiously enough, the sensitivity to dissociation was lower at the intermediate dose rate than at either the high or low one. Simple target theory analysis of the data indicates a target size for polysome dissociation in the range between a single ribosome and a disome. Amino-acid incorporation is more sensitive to radiation than is polysome content. Data obtained at the highest dose rate suggest that there is a second sensitive target which is considerably smaller than the more sensitive one.