cssi/SciSciGPT-SciSciNet huggingface dataset:
Who Pays for the "Social Cost" of Labor?

Although the minimum wage is one of the most commonly researched subjects, its treatment by economists has remained inadequate and led to misconceptions regarding its role in modern society. This philosophical piece offers a rebuttal to the conventional merit-based objection to the minimum wage and puts forward alternative lenses through which the moral appeal of the minimum wage should be (re-)evaluated. We argue that our evolutionary heritage can help us demystify the persistent popular support behind the minimum wage laws. In our framework, the minimum wage laws will be viewed as instrumental in meeting the "basic needs" of those who are offering productive contributions. The approach taken in this paper will supplement and modify old institutionalist framework and equip it with proper moral foundations.
Physical Abuse of Children

Cruelty toward and maltreatment of children has become a topic of much social concern during the past 20 years. The purpose of this chapter is to summarize the roots of this concern, analyze the magnitude of the problem, review current knowledge and, lastly, provide a framework for considering treatment, prediction, and prevention. Only physical abuse will be discussed; other forms of maltreatment such as sexual abuse, neglect, and institutional abuse are beyond the scope of this review. The terms abuse and maltreatment will be used synonymously and refer to inflicted trauma or injury by parents or other caregivers.
Using Interior-Point Methods within an Outer Approximation Framework for Mixed Integer Nonlinear Programming

Interior-point methods for nonlinear programming have been demonstrated to be quite efficient, especially for large scale problems, and, as such, they are ideal candidates for solving the nonlinear subproblems that arise in the solution of mixed-integer nonlinear programming problems via outer approximation. However, traditionally, infeasible primal-dual interior-point methods have had two main perceived deficiencies: (1) lack of infeasibility detection capabilities, and (2) poor performance after a warmstart. In this paper, we propose the exact primal-dual penalty approach as a means to overcome these deficiencies. The generality of this approach to handle any change to the problem makes it suitable for the outer approximation framework, where each nonlinear subproblem can differ from the others in the sequence in a variety of ways. Additionally, we examine cases where the nonlinear subproblems take on special forms, namely those of second-order cone programming problems and semidefinite programming problems. Encouraging numerical results are provided.
Literacy for Students with Low Vision: A Framework for Delivering Instruction.

This study identified the levels of direct and consultative instructional services needed for teaching literacy skills to students with low vision. The findings support the need to provide consiste...
Descent for Transfer Factors

In [I] we introduced the notion of transfer from a group over a local field to an associated endoscopic group, but did not prove its existence, nor do we do so in the present paper. Nonetheless we carry out what is probably an unavoidable step in any proof of existence: reduction to a local statement at the identity in the centralizer of a semisimple element, a favorite procedure of Harish Chandra that he referred to as descent.
Statewide Success of Staged Sacral Neuromodulation for the Treatment of Urinary Complaints in California (2005-2011).

Purpose Sacral neuromodulation (SNS) is approved by the Food and Drug Administration as a third-line treatment for refractory overactive bladder, idiopathic urinary retention, and fecal incontinence. Prior to implantation of an implantable pulse generator, all patients undergo a trial phase to ensure symptom improvement. The published success rates of progression from the test phase to permanent implant vary widely (range, 24% to >90%). We sought to characterize success rates using a statewide registry. Methods Using nonpublic data, we identified SNS procedures using the California Office of Statewide Planning and Development ambulatory surgery database from 2005 to 2011. A successful trial was defined as receiving a stage 2 generator implantation after trial lead placement. Multivariable logistic regression was performed to identify factors associated with staged success. Results During the study period, 1396 patients underwent a staged SNS procedure, with 962 (69%) subsequently undergoing generator placement. Successful trial rates were 72% for overactive bladder wet, 69% for urgency/frequency, 68% for interstitial cystitis, 67% for neurogenic bladder, and 57% for urinary retention. On multivariate logistic regression, only male sex (odds ratio, 0.51) and urinary retention [odds ratio, 0.54) were significantly associated with lower odds of success, whereas age, race/ethnicity, medical insurance, and placement at an academic or high-volume institution had no association. Conclusions The "real world" success rates for staged SNS implantation in California are less than those observed by some academic centers of excellence but better than previously reported for Medicare beneficiaries. Successful trial rates for interstitial cystitis and neurogenic voiding dysfunction are similar to refractory overactive bladder.
DEMENTIA-RELATED STIGMA RESEARCH: CAN WE MOVE THE STIGMA DIAL?

The projected increase in dementia world-wide will stress the ability of care systems to provide appropriate support for those with cognitive decline. Some individuals with dementia experience stigma, a set of negative and often discriminatory societal beliefs. Reducing dementia stigma could potentially lead to better care and a higher quality of life for people with dementia and their families. A recent systematic literature review examined world-wide evidence over the past decade on dementia-related stigma with a focus on: 1) how stigmatizing attitudes may present in various sub-groups, including in racial or ethnic minorities, 2) stigma assessment tools, and 3.) prospective or experimental approaches to assess or manage stigma. Results suggest pervasive stigma, possibly more severe in some ethnic sub-groups. The presentation will conclude with description of a recent pilot educational curriculum to address dementia-related stigma and preliminary experience with Alzheimer’s Association staff.
State government public goods spending and citizens' quality of life.

Abstract A growing literature across the social sciences uses individuals' self-assessments of their own well-being to evaluate the impact of public policy decisions on citizens' quality of life. To date, however, there has been no rigorous empirical investigation into how government spending specifically on public goods impacts well-being. Using individual-level data on respondents' self-reported happiness and detailed government spending data for the American states for 1976–2006, I find robust evidence that citizens report living happier lives when their state spends more (relative to the size of a state's economy) on providing public goods. As an important spuriousness check, I also show that this relationship does not hold for total government spending or for government spending on programs that are not (strictly speaking) public goods like education and welfare assistance to the poor. Moreover, the statistical relationship between public goods spending and happiness is substantively large and invariant across income, education, gender, and race/ethnicity lines – indicating that spending has broad benefits across society. These findings suggest that public goods spending can have important implications for the well-being of Americans and, more broadly, contribute to the growing literature on how government policy decisions concretely impact the quality of life that citizens experience.
Inferring Gene Regulatory Networks of Metabolic Enzymes Using Gradient Boosted Trees

Metabolic reprogramming is a hallmark of cancer. In cancer cells, transcription factors (TFs) govern metabolic reprogramming through abnormally increasing or decreasing the transcription rate of metabolic enzymes, which provides cancer cells growth advantages and concurrently leads to the altered metabolic phenotypes observed in many cancers. Consequently, targeting TFs that govern metabolic reprogramming can be highly effective for novel cancer therapeutics. In this paper, we present TFmeta, a machine learning approach to uncover TFs that govern reprogramming of cancer metabolism. Our approach achieves the state-of-the-art performance in reconstructing relations between TFs and their target genes on public benchmark datasets. Leveraging TF binding profiles inferred from genome-wide ChIP-seq experiments and 150 RNA-seq samples from 75 paired cancerous and non-cancerous human lung tissues, our approach predicted 19 key TFs that may be the major regulators of the gene expression changes of metabolic enzymes of the central metabolic pathway glycolysis, which may underlie the dysregulation of glycolysis in non-small-cell lung cancer patients.
Exposure therapy for generalized anxiety disorder in children and adolescents

Abstract Genital warts are a common sexually transmitted disease (STD) in young people usually caused by human papillomavirus (HPV) 6 or 11. Genital warts are a significant public health problem worldwide. However, there are now some countries recording significant falls in the incidence of GW in specific age groups following the introduction of prophylactic vaccines containing HPV 6 and 11 virus-like particles (VLPs). Laryngeal papillomatosis is a rare disease seen in both young children and adults, usually caused by HPV 6 or 11. In children, the disease is acquired by vertical transmission from the mother during childbirth, whereas in adults it is usually acquired through oro-genital sexual activity. Most commonly, there are multiple lesions in the larynx, although occasionally there is spread to the lower respiratory tract. In young children, the lesions very frequently recur after treatment, and this also occurs, but less frequently, in adults. Following the introduction of HPV 6 and 11 VLP vaccines, evidence has emerged in both Australia and Canada of a fall in the incidence of juvenile onset laryngeal papillomatosis.
The effect of an oxytocin washout period on blood loss at cesarean delivery.

Objectives Prolonged oxytocin exposure may result in increased blood loss during delivery. Our objective was to determine whether an oxytocin rest period before cesarean delivery had an impact on blood loss. Methods We performed a retrospective cohort study of women who underwent primary cesarean delivery after oxytocin augmentation. The primary outcome was change between pre- and postoperative hematocrit (Hct) in women with less than 60-min oxytocin rest period ( 60 min). Results There was no difference in demographic characteristics (age, BMI, or gestational age at delivery) between the two groups. Women in the >60 min group had a higher cumulative dose and longer duration of oxytocin administration. There was no significant difference in change in Hct between the two groups when controlling for these factors. Conclusions We did not find a significant correlation between the duration of the oxytocin rest period and blood loss. Oxytocin washout periods of greater than 60 min may not result in decreased blood loss at cesarean delivery, and thus, women may not benefit from such oxytocin washout periods.
Creatures of the State? Metropolitan Counties Compensated for State Inaction in Initial U.S. Response to Covid-19 Pandemic

Societal responses to crises require coordination at multiple levels of organization. Exploring early efforts to contain COVID-19 in the U.S., we argue that local governments can act to ensure systemic resilience and recovery when higher-level governments fail to do so. Event history analyses show that large, more urban areas experience COVID-19 more intensely due to high population density and denser socioeconomic networks. But metropolitan counties were also among the first to adopt shelter-in-place orders. Analyzing the statistical predictors of when counties moved before their states, we find that the hierarchy of counties by size and economic integration matters for the timing of orders, where both factors predict earlier shelter-in-place orders. In line with sociological theories of urban governance, we also find evidence of an important governance dimension to the timing of orders. Liberal counties in conservative states were more than twice as likely to adopt a policy and implement one earlier in the pandemic, suggesting that tensions about how to resolve collective governance problems are important in the socio-temporal dynamic of responses to COVID-19. We explain this behavior as a substitution effect in which more urban local governments, driven by risk and necessity, step up into the action vacuum left by higher levels of government and become national policy leaders and innovators.
Association Between Physical Performance and Cognitive Function in Older Adults Across Multiple Studies: A Pooled Analysis Study.

Background and Objectives While several studies have examined the association between cognitive and physical function, the consistency of these associations across functional contexts is unclear. The consistency of the association between cognitive and physical function performance was examined at baseline across 17 clinical studies with diverse and heterogeneous conditions such as overweight/obese, sedentary, at risk for a mobility disability, osteoarthritis, low vitamin D, or had signs of cognitive impairment. Research Design and Methods Data are from 1,388 adults 50 years and older who completed a cognitive and physical function assessment as part of a research study at the Wake Forest Alzheimer's Disease Research Center or the Wake Forest Older Americans Independence Center. Linear regression models were used to relate cognitive measures (Mini-Mental Status Examination, Montreal Cognitive Assessment, and the Digit Symbol Substitution Task) and physical measures (the Short Physical Performance Battery and hand grip strength) for the whole sample and treat each study as a fixed effect. All models controlled for age, sex, race, and body mass index. Results Overall, there was a significant association between higher scores on the Mini-Mental Status Examination (per standard deviation) and better physical function performance (Short Physical Performance Battery score b = 0.24, p < .001) and its components (gait speed, chair rise, and standing balance; ps < .05). Higher scores on the Montreal Cognitive Assessment produced similar results (Short Physical Performance Battery score b = 0.31, p ≤ .001), and higher scores on the Digit Symbol Substitution Task were also significantly associated with a better Short Physical Performance Battery score (b = 0.75, p < .001). The relationship between Digit Symbol Substitution Task and physical function performance demonstrated a stronger magnitude of association compared to the Mini-Mental Status Examination or Montreal Cognitive Assessment. Discussion and Implications Older adults with heterogeneous health conditions showed a consistent pattern between better cognitive function and better physical function performance with the strongest association among Digit Symbol Substitution Task scores.
Signatures of host–pathogen evolutionary conflict reveal MISTR—A conserved MItochondrial STress Response network

Host-pathogen conflicts leave genetic signatures in genes that are critical for host defense functions. Using these "molecular scars" as a guide to discover gene functions, we discovered a vertebrate-specific MItochondrial STress Response (MISTR) circuit. MISTR proteins are associated with electron transport chain (ETC) factors and activated by stress signals such as interferon gamma (IFNγ) and hypoxia. Upon stress, ultraconserved microRNAs (miRNAs) down-regulate MISTR1(NDUFA4) followed by replacement with paralogs MItochondrial STress Response AntiViral (MISTRAV) and/or MItochondrial STress Response Hypoxia (MISTRH). While cells lacking MISTR1(NDUFA4) are more sensitive to chemical and viral apoptotic triggers, cells lacking MISTRAV or expressing the squirrelpox virus-encoded vMISTRAV exhibit resistance to the same insults. Rapid evolution signatures across primate genomes for MISTR1(NDUFA4) and MISTRAV indicate recent and ongoing conflicts with pathogens. MISTR homologs are also found in plants, yeasts, a fish virus, and an algal virus indicating ancient origins and suggesting diverse means of altering mitochondrial function under stress. The discovery of MISTR circuitry highlights the use of evolution-guided studies to reveal fundamental biological processes.
Exploring the implications of the new ICD-10-CM classification system for injury surveillance: analysis of dually coded data from two medical centres.

Introduction External cause of injury matrices is used to classify mechanisms/causes of injuries for surveillance and research. Little is known about the performance of the Centers for Disease Control and Prevention’s new external cause of injury matrix for Clinical Modification of the 10th Revision of the International Classification of Diseases (ICD-10-CM), compared with the ICD-9-CM version. Methods Dually coded (ICD-9-CM and ICD-10-CM) administrative data were obtained from two major academic trauma centres. Injury-related cases were identified and categorised by mechanism/cause and manner/intent. Comparability ratios (CR) were used to estimate the net impact of changing from ICD-9-CM to ICD-10-CM on the number of cases classified to each mechanism/cause category. Chamberlain’s percent positive agreements (PPA) were calculated and McNemar’s test was used to assess the significance of observed classification differences. Results Of 4832 and 5211 dual-coded records from the two centres, 632 and 520 with injury-related principal diagnoses and external cause codes in both ICD-9-CM and ICD-10-CM were identified. CRs for the mechanisms/causes with at least 20 records ranged from 0.85 to 1.9 at one centre and from 0.97 to 1.07 at the other. Among these mechanisms/causes, PPAs ranged from 33% for ‘other transport’ to 94% for poisoning at one centre, and from 75% for ‘other transport’ to 100% for fires/burns at the other centre. Case assignment differed significantly for falls, motor vehicle traffic, other transport, and ‘struck by/against’ injuries at one centre, and for ‘other pedal cyclist’ at the other centre. Conclusion Switching to ICD-10-CM and the new external cause of injury matrix may affect injury surveillance and research, especially for certain mechanisms/causes.
SEPSIS AND MENINGITIS IN PAEDIATRIC INTENSIVE CARE: CLINICAL AND LABORATORY FEATURES ON ADMISSION

We undertook this study to determine the relative frequency of meningitis and sepsis in a paediatric intensive care unit (PICU) and to define the clinical features of children with meningitis and sepsis at the time of admission to the PICU. We reviewed the medical records of 162 patients with sepsis and meningitis, in the PICU, from 2000 to 2007. Among these patients 93 (57.4%) had meningitis, 125 (77.2%) had sepsis and 78 (48.1%) patients had bacteraemia, 108 patients (66.7%) had no meningeal signs. Ages ranged from 1 month to 14 years (mean 1–5 years); boys 98 (60.5%), girls 64 (39.5%). Temperature at the time of admission was greater than 38°C in 142 (87.7%) patients. Peripheral white cell count was from 200 to 58 000/mm3 (mean 14 164/mm3). Leucocytosis was noted in 64 (41.6%) patients and leucopenia in 35 (22.7%). 113 (69.8%) patients had a lumbar puncture performed. Six had lumbar puncture but were haemorrhagic and those 43 patients who did not have lumbar punctures had diffuse intravascular coagulation. The species of microorganism in 40 patients (24.7%) was meningococcus group B, in 15 patients (9.3%) pneumococcus and in 56 patients (34.6%) no microorganism was found. 113 of the 162 (69.8%) patients received intravenous ceftriaxone. 151 (92.6%) patients recovered and 11 (6.8%) died. Meningitis and sepsis remain a serious problem in the PICU despite existing guidelines of therapy and prognostic signs at the time of admission to the PICU.
The context dependent effects of host competence, competition, and the pathogen transmission mode on disease prevalence

ABSTRACT Biodiversity in communities is changing globally, including the gain and loss of host species in host-pathogen communities. Increased host diversity can cause infection prevalence in a focal host to increase (amplification) or decrease (dilution). However, it is unclear what general rules govern the context dependent effects, in part because theories for pathogens with different transmission modes have developed largely independently. Using a two-host model, we explore how the pathogen transmission mode and characteristics of a second host (disease competence and competitive ability) influence disease prevalence in a focal host. Our work shows how the theories for pathogens with environmental transmission, density-dependent direct transmission, and frequency-dependent direct transmission can be unified. Our work also identifies general rules about how host and pathogen characteristics affect amplification/dilution. For example, higher competence hosts promote amplification, unless they are strong interspecific competitors; strong interspecific competitors promote dilution, unless they are large sources of new infections; and dilution occurs under frequency-dependent direct transmission more than density-dependent direct transmission, unless interspecific host competition is sufficiently strong. Our work helps explain how the characteristics of the pathogen and a second host affect disease prevalence in a focal host.
Mitotic Cycle Regulation. II. Traveling Waves

M-phase Promoting Factor (MPF) is a heterodimeric protein kinase (CycB:Cdk1) that triggers mitosis in eukaryotic cells. During interphase, MPF is inhibited by an inactivating phosphorylation of its kinase subunit (Cdk1). At the G2/M transition, MPF is abruptly activated by autocatalytic removal of the inhibitory phosphate group. These properties make mitotic entry a ‘bistable’ system (coexistence of states of low and high MPF activity), as demonstrated in an earlier case study, ‘Mitotic Cycle Regulation. I. Oscillations and Bistability.’ In this case study, we show that a bistable dynamical system, when coupled in physical space by molecular diffusion, can support a wave of excitation (MPF converted from low to high activity) that travels through space at a constant speed, \( c=a\sqrt{kD} \), where k = rate constant for autocatalytic activation of MPF, D = diffusion constant of MPF, and a = proportionality constant. We show how to calculate the traveling wave by numerical solution of the reaction-diffusion equation, and we compare the results of a model of MPF activation in frog egg extracts to recent experimental measurements of these waves.
Epitaxial growth and improved electronic properties of (Bi1−xSbx)2Te3 thin films grown on sapphire (0001) substrates: The influence of Sb content and the annealing

Abstract In this research, we report on the epitaxial growth of basal plane-oriented (Bi1−xSbx)2Te3 films (0 ≤ x ≤ 1) on sapphire (0001) substrates through Molecular Beam Epitaxy (MBE) and demonstrate the influence of composition, crystal orientation and post-annealing process on their electronic properties. The as-grown (Bi1−xSbx)2Te3 films change gradually from a strong n-type to a strong p-type conduction when the Sb content increases from 0 to 1, which is attributed to the charge carrier compensation between the n-type TeBi and p-type SbTe antisite defects. The crossover between the n- and p-type conduction is found for x between 0.6 and 0.7. We also find that post-annealing (at 580 K) is beneficial for the electronic properties of the p-type (Bi1−xSbx)2Te3 films: they attain improved carrier mobility and significantly increased hole density. However, annealing plays a negative role in the electronic properties of the n-type structures leading to an enhanced resistivity as well as a reduced Seebeck coefficient. The most plausible explanation for such annealing effects is an introduction of p-type defects in both the n-type and p-type (Bi1−xSbx)2Te3 films. The as-grown Bi2Te3 film possesses the largest thermoelectric power factor among all n-type films, reaching 4.1 and 2.5 mWm−1 K−2 at 122 and 300 K respectively, due to the high carrier mobility and proper carrier doping. In contrast, a remarkably improved power factor in p-type (Bi1−xSbx)2Te3 films is achieved upon annealing at 580 K for 1 h. The highest power factor in p-type Bi0.6Sb1.4Te3 and Sb2Te3 films is obtained at around 150 K and it increases from 0.2 mWm−1 K−2 (Bi0.6Sb1.4Te3) and 1.8 mWm−1 K−2 (Sb2Te3) for the as-grown films to 3.5 mWm−1 K−2, respectively 3.7 mWm−1 K−2 for the annealed films. The highly crystalline nature of (Bi1−xSbx)2Te3 films grown by MBE assures excellent carrier mobility and is a contributing factor to their outstanding power factors.
The Quadratic Map

There are several ways to examine the dynamics of the quadratic map defined by f r (x) = rx(1−x). The image above is from a demonstration that shows the bifurcation diagram for f r , while allowing the user to move a slider (the red line) which causes the corresponding cobweb plot to appear as well. The example shown has r set to 3.84, for which the limiting behavior is a 3-cycle.
Chronic Hypoxia-Enhanced Murine Pulmonary Vasoconstriction: Role of Superoxide and gp91phox

Chronic hypoxia (CH) is a common cause of pulmonary hypertension (PH). Accumulating evidence suggests that changes in the activity of endothelin (ET)-1 receptors may play an important role in CH-induced PH. After 3 weeks of CH (10% O 2 ) exposure, we found that the isolated intra-pulmonary artery (PA) constrictor response to ET-1 was significantly increased in wild-type (wt) mice. The administration of Cu/Zn superoxide dismutase (SOD) markedly reduced the CH-enhanced maximal PA constrictor response to ET-1, demonstrating the contribution of superoxide to CH-enhanced PA constrictor responses. Using mice that are completely deficient in gp91 phox (a subunit protein of the superoxide producing nicotinamide adenine dinucleotide phosphate [NADPH] oxidase), we found that CH-enhanced PA constriction to ET-1 was completely blocked (decreases in mean [± SE] maximal isometric tension from 5.43 ± 0.35 to 3.33 ± 0.19 mN; n = 7; p phox knockout mice were exposed to CH, they had significantly reduced levels of superoxide compared to CH-treated wt mice. Our results demonstrate that the CH-enhanced PA constrictor response to ET-1 is mediated by NADPH oxidase (gp91 phox )-derived superoxide overproduction that may contribute to the pathogenesis of CH-induced PH.
Regulation of intracellular pH in alveolar epithelial cells.

Alveolar type II epithelial cells in adult mammalian lungs actively transport salt and water, secrete surfactant, and differentiate into type I cells under normal conditions and following lung injury. It has become increasingly apparent that, like all epithelial cells, alveolar pneumocytes have evolved specialized ion transport mechanisms by which they regulate their intracellular pH (pHi). pHi is an important biological parameter in all living cells whose regulation is necessary for normal cellular homeostasis. pHi, and the ion transport mechanisms by which it is regulated, may contribute to many cellular processes, including transcellular transport, cell volume and osmolarity regulation, and intracellular transport, cell volume and osmolarity regulation, and intracellular electrolyte composition. Moreover, changes in pHi may serve as intracellular signals for biological processes such as cell growth, proliferation, and differentiation. We review herein the general principles of pHi regulation in epithelia and describe the mechanisms and effects of pHi regulation in alveolar pneumocytes. Many of the critical issues in current pulmonary research involve processes that pHi is most likely to affect, including maintenance of alveolar epithelial barrier integrity, development and maintenance of epithelial polarity, epithelial proliferation and differentiation, and regulation of transepithelial transport with respect to alveolar fluid balance in normal individuals and in those with excess alveolar fluid (i.e., pulmonary edema). Investigations into the regulation of pHi in alveolar pneumocytes and the regulatory effects of pHi in turn on other cellular processes are likely to yield information important to the understanding of lung biology and pulmonary disease.
Stratified Coastal Trapped Waves and Mean Flows

Abstract : Our long term goals are to identify the roles that rectified subinertial waves and mesoscale motions play in the mean-flow transport of fluid properties in the coastal ocean and to apply these ideas to cross-margin transport of physical, chemical, and biological properties. In addition, we are interested in the interaction and relative effect of wave-driven transport verses frictionally driven boundary layer transport. Coastal waves and wave-generated mean flows are studied in a stratified, rotating model ocean. Waves trapped to the coast are generated by time-dependent flow over a sloping and irregular bottom. In this study, we will study the rectified flow resulting from oscillatory forcing over a sloping bottom, both with and without additional ridges, and with and without stratification. Short-term goals of this study include quantifying the evolution of the vertical structure of the along-slope mean flow driven by non-linear interactions of the coastal trapped wave and damped by friction. The effects of stratification on the cross-slope overturning circulation will be examined to evaluate the strength of wave-driven mean flow verses frictionally driven flow.
Electronic-transport behavior in single-crystalline Ba 0.03 Sr 0.97 TiO 3

Simultaneous measurements of electrical conductivity \ensuremath{\sigma} and thermoelectric power Q were performed on a single crystal of ${\mathrm{Ba}}_{0.03}$${\mathrm{Sr}}_{0.97}$${\mathrm{TiO}}_{3}$ over an extensive range of temperature (500--1100?deC) and oxygen partial pressure (${10}^{\mathrm{\ensuremath{-}}18}$--1 atm) under thermal-equilibrium conditions. Analysis of the atmosphere dependence of \ensuremath{\sigma} and Q were found to be consistent with a defect model based on the generation and annihilation of shallow-donor-like oxygen vacancies and compensating background acceptor impurities. Following a theoretical approach proposed by Becker and Frederikse and by Jonker, analysis of the combined \ensuremath{\sigma} and Q data allowed, for the first time, determination of both electron [${\ensuremath{\mu}}_{e}$(950 ?(deC)=0.23 ${\mathrm{cm}}^{2}$/V?c] and hole [${\ensuremath{\mu}}_{e}$(950 ?(deC)=0.10 cm/V?c] mobilities at elevated temperatures. Further, large derived values for the electronic scattering factors (${A}_{e}$,${A}_{h}$=3.0) and temperature-independent Q-versus-${\mathrm{log}}_{10}$\ensuremath{\sigma} slopes strongly support a nonactivated large-polaron mobility mechanism for both electrons and holes.
Modulation of membrane cholesterol content in cultured LLC-PK1 cells

Abstract This study was designed to develop a cell culture model to evaluate the effect of cell membrane fluidity on the function of drug carrier proteins. Fluidity of the cell membrane has been linked to its cholesterol content. LLC-PK 1 cells were grown as a monolayer and were treated with a BSA-PVP-cholesterol complex in time-dependent studies. The total cholesterol content of the cells was increased 4-fold (from 52 to 200 fmol/mg protein) as a result of this treatment. The cholesterol increase appears to level off at 2 h of treatment. Most of the incorporated cholesterol (77%) was determined to be free cholesterol, the rest being esterified. Membrane fractions of the treated cells were isolated and were determined to carry 88% of the cholesterol content. The studies indicate that it is feasible to deliver cholesterol to cultured epithelial cells and that LLC-PK 1 cell monolayers can be used as a model for such studies.
Catalytic Decomposition of Ammonium Nitrate in Superheated Aqueous Solutions

The decomposition of aqueous ammonium nitrate at elevated temperatures and pressures is examined as a function of chloride, nitrate, and total acidity. Catalysis requiring both chloride and acid wa...
Modeling Aerosols in Amine-based CO2 Capture☆

Abstract Controlling emission of gaseous and aerosolized pollutants is a critical function of CO2 capture systems using aqueous amine solvents. Absorption of species into aerosols suspended within flue gas, not mechanical entrainment, has been identified as a dominant volatile discharge route. This work investigated the effects of operating conditions on aerosol growth in a combined, PZ-based, absorber/water wash column through simulation using thermodynamic, kinetic, and transport models in Aspen Plus® in combination with an external aerosol model in MATLAB®. Aerosol transport equations included continuum-kinetic length-scale corrections. In the absorber, aerosols grow by continual uptake of CO2 and PZ. Subsequently, H2O condenses to return to saturation. Droplets grow faster in non-intercooled columns because the temperature bulge and leaner solvent increases available PZ in the bulk gas phase. Aerosols grow fastest where the solvent is lean and hot, i.e., above the temperature bulge. Droplets grow faster in the water wash because of elevated PH2O relative to that in the absorber. PH2O is proportional to the amine concentration in the wash loop. The growth mechanism in the water wash can be exploited to remove aerosols by increasing residence time or diluting the wash solution. Increasing aerosol size increases removal efficiency while minimizing the ΔP characteristic to particle collectors.
Dehydroheliamine, a trace alkaloid from the saguaro, Carnegiea gigantea (cactaceae)

Abstract Extraction of Carnegiea gigantea yielded a new 3,4-dihydroisoquinoline alkaloid, dehydroheliamine; the structure was confirmed by synthesis.
Study of propene metathesis on MoO3−x/Al2O3 catalysts; effect of diazomethane decomposition

Propene metathesis has been studied at 295 K and 1 atm in He or in H2 with MoO3−x/Al2O3 catalysts which were reduced at 673 K. Some catalysts were modified by exposing them to diazomethane vapor prior to testing. The diazomethane was synthesized shortly before use; it was stored by dissolving its vapor in di-n-butyl phthalate. Metathesis of the unmodified catalysts revealed an induction period during which the activity increased; this period is markedly shorter in H2 than in He. In He, metathesis is the sole reaction, in H2 it is accompanied by a prevailing hydrogenolysis. No induction period is visible for catalysts modified with diazomethane in accordance with the assumption that surface carbenes are reaction intermediates. The activity is, however, lowered by this treatment, as catalyst deactivation is enhanced by the pretreatment with diazomethane.
Dietary preferences in early lactation cows as affected by primary tastes and some common feed flavors.

Abstract A sequential elimination trial was conducted to test the effects of primary tastes on the preference ranking of TMR diets by six multiparous Holstein cows from 8 to 21 DIM. Four additives and a control were examined; the most preferred (highest total intake) was eliminated after segments of 5, 4, 3. and then 2 d. Diets tasting sweet (sucrose, 1.5% of dietary DM), sour (HCI, 1.25%), bitter (urea, l%), and salty (NaCl, 4%) were tested. Four of the cows most preferred the sweet diet, and DMI of that diet averaged 12.8% more than for the control, which was next preferred. The probability of a diet being chosen first when all diets were presented together was sucrose, .59; control, .36; urea, .04; NaCl, .01; and HCl, .003. Another experiment used the same procedure; however, the additives tested were anise, monosodium glutamate, dehydrated alfalfa meal flavor, and molasses flavor (1.48 g of flavor/kg of DM). Control and monosodium glutamate ranked first equally. The probability of choosing each flavor first in this set was .5 for the control and monosodium glutamate diets and
Identification of β-Adrenergic Receptors Using [3H]Dihydroalprenolol in Fetal Sheep Heart: Direct Evidence of Qualitative Similarity to the Receptors in Adult Sheep Heart

Summary: The fetal sheep heart responds to β-adrenergic stimuli; however, in vivo studies show the response of the fetal heart is less than that of the adult heart. We used [3H]dihydroalprenolol (DHA) to study directly β-adrenergic receptors in heart particulates of fetal sheep at term and adult sheep. [3H]DHA binding to fetal heart particulates was rapid, reversible (t1/2 = 2.9 ± 0.3 min), stereoselective, saturable (101.2 ± 7.4 fmoles/mg protein), and of high affinity (4.8 ± 0.4 nM). The rank order of agonists competing for [3H]DHA binding was isoproterenol (0.32 ± 0.10 μM) > epinephrine (1.19 ± 0.23 μM) ⋍ norepinephrine (2.67 ± 0.69 μM), which is compatible with β1-adrenergic potencies. [3H]DHA also bound to the adult sheep heart in a manner expected for β1-receptors. No difference in the binding affinity of [3H]DHA or agonists' competition was demonstrated between the fetal and adult sheep heart. Comparison of the concentration of β-adrenergic receptors in fetal and adult hearts was confounded by the choice of the denominator for unit expression. The concentration was higher in the adult when expressed as a function of protein content or 5′-nucleotidase activity (0.52 ± 0.07 versus 1.12 ± 0.06). However, there was no difference when tissue weight, Na+ − K+-ATPase, or NaF-stimulated adenylate cyclase was used. Furthermore, isoproterenol-stimulated adenylate cyclase and cardiac contractile response to a threshold dose of isoproterenol were identical in the fetal and adult sheep heart. We conclude that β-receptors can be studied with [3H]DHA in the fetal sheep heart, this receptor is qualitatively similar to the β-receptor in the adult sheep heart, and it is unlikely that there is a difference in the concentration of β-adrenergic receptors in fetal and adult sheep heart. Speculation: The interactions of adrenergic agents with cardiac β-adrenergic receptors in the term fetus are identical to those in the adult, and the receptor-adenylate cyclase coupling system reaches maturity before birth.
Use of Volatile Chloroorganics as a Measure of the Rehabilitation of the St. Louis River and Bay

Abstract A major source of chloroorganic discharge into the St. Louis River system is a pulp mill located 33 km upstream from Lake Superior. The effect of diverting the pulp mill effluent to an advanced secondary treatment plant, located 33 km downstream, was examined using a “chloroform monitoring technique.” Chloroform, formed during the bleaching of pulp, was used as a tracer substance to follow the movement of the chloroorganic effluent plume originating from the pulp mill. The treatment plant was shown to be only partially effective in removing chloroorganics, indicating that the point source of chloroorganic discharge into the St. Louis River system has only been relocated.
Minorities and Urban Crime Are They the Cause or the Victims

Recent studies of crime in American cities have shown a major contributing factor to be the percentage of the population that is black. This relationship is "explained" by a variety of theories foc...
Modulation and spectral dynamics in semiconductor quantum-well lasers

In a practical quantum well structure, the separate confinement heterostructure is usually employed to confine the optical field in the waveguide and the injected carriers in the quantum well region. The fundamental Fermi-Dirac statistics results in that, in addition to the carrier population in the quantum well region, there is also a significant carrier population in the optical confining region (referred to as the state-filling effect in the quantum well structure). The differential gain depends on the rate of increase of the quasi Fermi energies with respect to the increase of injected carrier density. The presence of upper subbands with large density of states tends to clamp the Fermi energies thus leading to a degradation in the differential gain. The state filling effect also significantly affects the amplitude-phase coupling and the spectral linewidth of quantum well lasers as a direct consequence of its influence on the differential gain.
The effect of magnesium sulfate on maternal retinal blood flow in preeclampsia: a randomized placebo-controlled study.

OBJECTIVES: The purpose of this study was to determine the effect of a 6 gm intravenous bolus of magnesium sulfate on maternal brain blood flow velocity waveforms in patients with preeclampsia. Study Design: Twelve patients with preeclampsia were randomized to two groups and studied with Doppler ultrasonography before and immediately after infusion of either a 6 gm intravenous loading dose of magnesium sulfate or a placebo. The middle cerebral, common carotid, and internal carotid arteries were studied. RESULTS: Magnesium sulfate significantly reduced the pulsatility index in the middle cerebral artery (change in pulsatility index=−0.16 + 0.09) when compared with the placebo (change in pulsatility index=−0.02 + 0.06), p = 0.01. There were no significant changes in the Doppler indexes of the carotid vessels. CONCLUSIONS: These data suggest that magnesium sulfate vasodilates the smaller-diameter intracranial vessels distal to the middle cerebral artery and may exert its main effect in the prophylaxis and treatment of eclampsia by relieving cerebral ischemia.
Alpha-fetoprotein signal sequences: a proposed mechanism for subcellular localization and organelle targeting

Abstract Alpha-fetoprotein (AFP) is an oncofetal protein, classified in an “albuminoid” superfamily (with albumin and Vitamin-D binding (Gc) protein) comprising molecules with three characteristic globular domains. The cellular uptake and internalization of AFP and its subcellular compartmentalization has previously been reported in a multitude of cell types. Studies have also emerged which have detected and characterized binding proteins complexed to AFP in various cell membranes and intracellular compartments. However, the literature is devoid of any attempts to relate these binding proteins to possible intracellular trafficking interactions of AFP. Recombinant DNA mutation/deletion technology has provided a means to pinpoint the amino acid sequence location of organelle localization signals on various transcription factors and/or receptors. Several subdomain regions on AFP have been reported to mimic heptad dimerization regions of the steroid/thyroid nuclear receptors. In light of these transcription factor-like docking motifs reported for AFP, the present report purposes various subdomain regions which might constitute basic amino acid sequences resembling recognition signals for binding (dimerizing) proteins. AFP appears to possess multiple prototypic amino acid sequence cassettes on each domain which consist of (i) classical short, compact sequences found on both steroid and thyroid receptors; (ii) proto-signals resembling a steroid receptor type; and (iii) degenerative signal sequence similar to the thyroid/retinoic acid receptor type. The concepts identifying binding or escort proteins for AFP together with organelle signal sequences on AFP have been reconciled in a composite hypothesis to formulate a mechanism which could account for some of the growth-regulating properties described for AFP during the last decade.
Embrittlement by liquid U in some group VB and VIB metals and alloys during tensile loading at 1473 K

An investigation was conducted to determine the effect on tensile behavior of Ta, W, V, Nb, and a Ta-2.5 wt pct W alloy when they were exposed to liquid U. Tantalum, wolfram, and the Ta-2.5 wt pct W alloy were embrittled with a negligible reduction of cross section at failure, whereas V and Nb showed ductile behavior, with the samples necking down to a point. Tensile deformation of Ta in liquid U was also investigated at different displacement rates. It was found that ductility and strength increased with increasing displacement rate. The embrittlement in Ta, W, and the Ta-2.5 wt pct W alloy was associated with intergranular penetration of U, and the fracture surfaces showed evidence of grain boundary dissolution. At higher displacement rates, however, this evidence was less obvious. These results indicate that intergranular penetration of liquid U and tensile embrittlement in some of the Group VB and VIB metals correlate with low mutual solubility between the solid and liquid elements. It was also found that the thermo-dynamic criterion for intergranular penetration of liquid into a solid (grain boundary energy > 2 × liquid/solid interfacial energy) only applies to these systems.
Functional magnetic resonance imaging of cerebellar activation during the learning of a visuomotor dissociation task

We have used functional magnetic resonance imaging (fMRI) to study the changes in cerebellar activation that occur during the acquisition of motor skill in human subjects presented with a new task. The standard paradigm consisted of a center-out movement in which subjects used a joystick to superimposed a cursor onto viusual targets. Two variations of this paradigm were introduced: (1) a learning paradigm, where the relationship between movement of the joystick and cursor was reversed, requiring the learning of a visuomotor transformation to optimize performance and (2) a random paradigm, where the joystick/cursor relationship was changed randomly for each trial. Activation in the cerebellum was highest during the random paradigm and during the early stages of the learning paradigm. In the early stages of learning and during the random paradigm performance was poor with a decrease in the number of completed movements, and an increase in the time and length of movements. With repeated practice at the learning paradigm performance improbed and reached the same level of proficiency as in the standard task. Commensurate with the improbement in performance was a decrease in cerebellar activation, that is, activation in the cerebellum changed in a parallel, but inverse relationship with performance. Linear regression analysis demonstarated that the inverse correlation between cerebellar activation and motor performance was significant. Repeated practice at the random paradigm did not produce improvements in performance and cerebellar activity remained high. The data support the hypothesis that the cerebellum is strongly activated when motor performance is inaccurate, consistent with a role for the cerebellum in the detection of, and correction for visuomotor errors.
CSI–Chocolate Science Investigation and the Case of the Recipe Rip-Off: Using an Extended Problem-Based Scenario To Enhance High School Students’ Science Engagement

This paper discusses a K–12/university collaboration in which students participated in a four-day scenario-based summer STEM (science, technology, engineering, and mathematics) camp aimed at making difficult scientific concepts salient. This scenario, Jumpstart STEM–CSI: Chocolate Science Investigation (JSCSI), used open- and guided-inquiry methods to generate meaningful student engagement for 33 rising 8th through 12th graders. This paper presents curriculum for the scenario; reports results from postevent survey data regarding students’ self-reported gains in science motivation, science confidence, science knowledge, and students’ associations with scientifically-minded social niches; and illustrates how a scenario can incorporate the use of skills and knowledge from many disciplines and make them relevant to student learning, providing a context for STEM literacy. Implications for science educators are discussed.