cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermodynamic and Mass-Transfer Modeling of Carbon Dioxide Absorption into Aqueous 2-Amino-2-Methyl-1-Propanol

Explanations for the mass-transfer behavior of 2-amino-2-methyl-1-propanol (AMP) are conflicting, despite extensive study of the amine for CO2 capture. At equilibrium, aqueous AMP reacts with CO2 to give bicarbonate in a 1:1 ratio. Although this is the same stoichiometry as a tertiary amine, the reaction rate of AMP is 100 times faster. This work aims to explain the mass-transfer behavior of AMP, specifically the stoichiometry and kinetics. An eNRTL thermodynamic model was used to regress wetted-wall column mass-transfer data with two activity-based reactions: formation of carbamate and formation of bicarbonate. Data spanned 40–100 °C and 0.15–0.60 mol CO2/mol alk. The fitted carbamate rate constant is 3 orders of magnitude greater than the bicarbonate rate constant. Rapid carbamate formation explains the kinetics, while the stoichiometry is explained by the carbamate reverting in the bulk liquid to allow CO2 to form bicarbonate. Understanding the role of carbamate formation and diffusion in hindered amin...
Women's schooling, fertility, and child health outcomes: Evidence from Uganda's free primary education program

Abstract This paper examines the role of women's education on both fertility and child health in Uganda. To identify causal effects, I exploit the timing of a national reform that eliminated primary school fees in 1997 to implement a regression discontinuity design. At the cutoff, the reform increased educational attainment by nearly one year on average, with impacts across all grade levels through the end of secondary school. Women with more schooling both delay and reduce overall fertility, increase early child health investments, and have less chronically malnourished children. In terms of mechanisms, women with additional schooling do not abstain more from sex as adolescents, but they are more likely to have used contraceptives before a first pregnancy and they delay marriage. Other downstream effects include improved employment outcomes and greater wealth.
Quantitative Biomedical Optics: Theory, Methods, and Applications

This is the textbook and reference resource that instructors, students, and researchers in biomedical optics have been waiting for. Comprehensive and up to date, it covers a broad range of areas in biomedical optics, from light interactions at the single-photon and single-biomolecule levels, to the diffusion regime of light propagation in tissue. Subjects covered include spectroscopic techniques (fluorescence, Raman, infrared, near-infrared, and elastic scattering), imaging techniques (diffuse optical tomography, photoacoustic imaging, several forms of modern microscopy, and optical coherence tomography), and laser-tissue interactions, including optical tweezers. Topics are developed from the fundamental principles of physical science, with intuitive explanations, while rigorous mathematical formalisms of theoretical treatments are also provided. For each technique, descriptions of relevant instrumentation and examples of biomedical applications are outlined, and each chapter benefits from references and suggested resources for further reading, and exercise problems with answers to selected problems.
Fluorophore Labeling, Nanodisc Reconstitution and Single-molecule Observation of a G Protein-coupled Receptor

Activation of G protein-coupled receptors (GPCRs) by agonist ligands is mediated by a transition from an inactive to active receptor conformation. We describe a novel single-molecule assay that monitors activation-linked conformational transitions in individual GPCR molecules in real-time. The receptor is site-specifically labeled with a Cy3 fluorescence probe at the end of trans-membrane helix 6 and reconstituted in phospholipid nanodiscs tethered to a microscope slide. Individual receptor molecules are then monitored over time by single-molecule total internal reflection fluorescence microscopy, revealing spontaneous transitions between inactive and active-like conformations. The assay provides information on the equilibrium distribution of inactive and active receptor conformations and the rate constants for conformational exchange. The experiments can be performed in the absence of ligands, revealing the spontaneous conformational transitions responsible for basal signaling activity, or in the presence of agonist or inverse agonist ligands, revealing how the ligands alter the dynamics of the receptor to either stimulate or repress signaling activity. The resulting mechanistic information is useful for the design of improved GPCR-targeting drugs. The single-molecule assay is described in the context of the β2 adrenergic receptor, but can be extended to a variety of GPCRs.
Chronic hindbrain administration of oxytocin is sufficient to elicit weight loss in diet-induced obese rats

Oxytocin (OT) administration elicits weight loss in diet-induced obese (DIO) rodents, nonhuman primates, and humans by reducing energy intake and increasing energy expenditure. Although the neurocircuitry underlying these effects remains uncertain, OT neurons in the paraventricular nucleus are positioned to control both energy intake and sympathetic nervous system outflow to interscapular brown adipose tissue (BAT) through projections to the hindbrain nucleus of the solitary tract and spinal cord. The current work was undertaken to examine whether central OT increases BAT thermogenesis, whether this effect involves hindbrain OT receptors (OTRs), and whether such effects are associated with sustained weight loss following chronic administration. To assess OT-elicited changes in BAT thermogenesis, we measured the effects of intracerebroventricular administration of OT on interscapular BAT temperature in rats and mice. Because fourth ventricular (4V) infusion targets hindbrain OTRs, whereas third ventricular (3V) administration targets both forebrain and hindbrain OTRs, we compared responses to OT following chronic 3V infusion in DIO rats and mice and chronic 4V infusion in DIO rats. We report that chronic 4V infusion of OT into two distinct rat models recapitulates the effects of 3V OT to ameliorate DIO by reducing fat mass. While reduced food intake contributes to this effect, our finding that 4V OT also increases BAT thermogenesis suggests that increased energy expenditure may contribute as well. Collectively, these findings support the hypothesis that, in DIO rats, OT action in the hindbrain evokes sustained weight loss by reducing energy intake and increasing BAT thermogenesis.
Routine pathologic examination of tonsillectomy specimens: A 10-year experience at a tertiary care children's hospital.

Abstract Objective To review histopathologic diagnoses from tonsillectomy specimens and determine whether routine pathologic exam is necessary. Methods Pathology reports of patients undergoing tonsillectomy from 2005 to 2014 at our pediatric tertiary care hospital were reviewed. Histopathologic diagnoses were recorded with special attention to identification of malignancy. Results A total of 8807 paired tonsil specimens were sent to pathology over a 10-year course. Gross analysis was performed on all. Microscopic histopathologic analysis was performed on 612 (6.95%) specimens with all but one demonstrating strictly reactive lymphoid hyperplasia. The single specimen (0.16%) demonstrated follicular hyperplasia with focal necrotizing granulomatous lymphadenitis without organisms identified on special staining. The surgeon requested pathologic diagnosis to rule out lymphoma in 4 of 8087 (0.05%) of the specimens. No malignancies were identified. The approximate charges for gross examination of a paired tonsillectomy specimen and microscopic examination were $136.10 and $294.54, respectively. Over the 10 year period of the study, total charges were estimated at $1,115,340 (gross) and $180,258 (microscopic). Discussion Microscopic analysis of tonsil specimens is unlikely to identify abnormal pathology that changes patient management. This study suggests that neither gross nor microscopic pathologic examination of tonsillectomy specimens is necessary on a routine basis. Histologic analysis of tonsils should be requested only on a case by case basis when clinical suspicion for malignancy is high. Avoiding routine pathologic exam of tonsils may be cost effective and medically safe.
Pleasure as a sign of moral virtue in the Nicomachean ethics

Etude du lien entre plaisir et vertu morale chez Aristote. Defendant une lecture naturelle des passages de l'«Ethique a Nicomaque», l'A. distingue deux conceptions du plaisir et de la peine comme criteres de l'activite vertueuse et de l'activite vicieuse: l'une physique, l'autre propositionnelle.
Probabilistic Approach to the Rounding Problem with Applications to Fair Representation

Failure to add to 100% occurs frequently for sums of percentages in reported sets of tables. It occurs so frequently, that if many sums of percentages add to exactly 100% in a reported set of tables, one begins to suspect the reporter of forcing the situation. Extending the pioneer works of Mosteller, Youtz and Zahn (1967) and of Diaconis and Freedman (1979) who assess the probability that a table of conventionally (MYZ) rounded proportions adds to 1, Balinski and Rachev (1992) introduced some rules of rounding that can improve the conventional rule. Investigating and developing further the so-called K-stationary divisor rules of rounding we compute, for several of these rules, the limiting probability that the rounded percentages add to 100%. We build up a bridge between the problem of rounding and the problem of apportionment. We apply the theory of apportionment in allocating representation among geographical regions in Greece and among states in U.S.A. We investigate and comment on the methods of apportionment currently being used in the two countries, as well as on other possible options including some K-stationary methods.
Pigeons simultaneously attend to static and dynamic features of complex displays

The simultaneous processing and attention to temporally dynamic and static features remains an open and important question in theories of avian visual cognition. Here, four pigeons (Columba livia) learned to discriminate complex displays involving concurrently available static and dynamic features. These displays consisted of 20 elements built from combinations of two, binary-valued, static visual dimensions: red vs. green element color, large vs. small element size; and two binary-valued dynamic dimensions; fast vs slow element motion, right vs up motion direction. One combination of these four features was reinforced on a VI schedule. The remaining 15 combinations of element color, size, speed and direction were never reinforced. During acquisition, all four dimensions were simultaneously discriminated. Varying the number of elements revealed that a single element was sufficient to support discrimination of all four dimensions. The pigeons agreed on the relative discriminability of stimuli within and across the different dimensions, with the difference in motion direction being the hardest for all birds. Redundant facilitation suggested rapid, perhaps parallel, processing of both dynamic and static features. No attentional trade-offs between dynamic or static dimensions were observed. These results agree with theories of avian vision employing the notion of multiple independent channels for different types of information.
Effects of Dexmethylphenidate on Targeted and Non-Targeted Behaviours during Functional Analyses: A Brief Report.

Objective: This study evaluated the effects of dexmethylphenidate on problem behavior during functional analyses conducted across dexmethylphenidate and placebo conditions for a child with multiple...
Spilling Over: How Participating in After-School Organized Activities Predicts Students’ Engagement

Abstract There is a growing interest in the academic benefits of participating in organized after-school activities. In this chapter, we review the research on the effects of participation in three types of organized after-school activities, including extracurricular activities (e.g., school-based sports clubs), after-school programs (e.g., 21st Century Community Learning Centers), and youth development programs (e.g., Boys and Girls Clubs of America) on academic achievement, student engagement, and attendance, highlighting variations in these relations by individual and setting-level characteristics. We discuss the mechanisms linking participation in organized after-school activities to engagement including (1) the academic requirements, (2) components of participation, (3) cognitive skills, (4) norms and values, (5) relationships, and (6) opportunities for social and emotional learning. The chapter concludes with a discussion of the implications of these findings for future research and practice, paying particular attention to strategies for creating more engaging organized after-school activities.
Proton pump inhibitors: placing putative adverse effects in proper perspective.

PURPOSE OF REVIEW This review summarizes the past year's literature, both clinical and basic science, regarding potential adverse effects of proton pump inhibitors (PPIs). RECENT FINDINGS PPIs are amongst the most widely prescribed and over-prescribed medications worldwide. Although generally considered well tolerated, epidemiologic studies that mine large databases have reported a panoply of putative adverse effects associated with PPIs. It should be emphasized that the quality of the evidence underlying most of these associations is very low and the studies, by design, cannot ascribe cause and effect. These associations continue to be sensationalized in the media and misinterpreted by providers and patients. The unintended consequences are that patients who require PPIs, such as those taking dual antiplatelet agents, are not being prescribed or taking these necessary medications. In addition, physicians are spending an inordinate amount of additional time placing these findings into proper perspective for their patients and reassuring them upon initiating PPI treatment as well as at every follow-up visit. SUMMARY Most of the recent publicized putative serious adverse effects attributed to PPIs rely on observational data and have not been confirmed in prospective randomized trials. Nevertheless, PPIs should be prescribed for valid indications and when prescribed long-term, they should be used at the lowest effective dose and the need for their use periodically reassessed.
A low activity ion source for measurement of atmospheric gases by CIMS

Abstract. Most I--CIMS (iodide-chemical ionization mass spectrometers) for measurement of atmospheric trace gases utilize a radioactive ion source with an initial activity of 10 or 20 mCi of 210Po. In this work, we characterize a 210Po ion source with an initial activity of 1.5 mCi that can be easily constructed from commercially available components. The low level of radioactive activity of this source significantly reduces complications with storage and shipping relative to higher activity sources. We compare the sensitivity of the low activity source (LAS) to a standard 20 mCi source, as a function of carrier gas flow and flow tube pressure, for peroxyacetyl nitrate (PAN), formic acid (HCO2H) molecular chlorine (Cl2), and nitryl chloride (ClNO2) using an I--CIMS. The LAS provides 2 to 5 times less sensitivity than that of the standard source even though the ratio of activity is approximately 13. However, detection limits of less than 2 pptv for the tested compounds are achieved for integration times of the order of a minute. The sensitivity of the LAS is less dependent on the magnitude of the carrier gas than a standard source. In addition, the LAS provides maximum sensitivity at relatively low carrier gas flows. Finally, we demonstrate that the LAS can be used to measure PAN in the remote atmosphere from an aircraft by showing data obtained on the NASA DC-8 during the Atmospheric Tomography (ATom) mission. In summary, the LAS may be an excellent substitute for a standard ion source in some field applications.
Heterogeneity of Treatment Effects of PMTO in Foster Care: A Latent Profile Transition Analysis

Parent Management Training-Oregon (PMTO) model has demonstrated significantly improvements in parental functioning and child’s social skills and socio-emotional well-being among families whose children were placed in foster care. Yet, there is a dearth of studies examining for whom PMTO works the best. The aim of this study was to examine the potential familial typologies in relation to parental and children’s functioning and how these typologies change after participating in PMTO. The sample consisted of 918 children in foster care and their biological parents recruited in September 2012-2014 in a Midwestern state and randomized to in-home PMTO (n = 461) or services as usual (SAU) (n = 457). Latent profile transition analysis examines how participation in PMTO influences changes in children’s behavior and their biological parent’s functioning over time while placed in out-of-home care. PMTO families reporting high parental functioning and children’s social-emotional outcomes were more likely to move to a higher functioning class (OR = 0.22, p = 0.01) than SAU families all characteristics equal. Yet, when families experienced poor parental functioning of all four types, PMTO was not helpful in improving parent’s functioning and children’s problem behaviors (OR = 4.41, p = 0.01). This study provides empirical support for child welfare agencies to sustain the PMTO program to improve children’s emotional and behavioral health.
Intergenerational family conflict and ethnic identity among Chinese American college students.

There has been a call for increased attention to experiences of sociocultural contexts and their role in mental health and help-seeking among specific subgroups of Asian Americans (Leong, Park, & Kalibatseva, 2013). In particular, as suggested by the integrative contextual framework of minority youth development (Garcia Coll & Marks, 2012), racial minority adolescents and emerging adults develop identity and psychological well-being through their experiences within multiple contexts. Guided by this perspective, the present study examined the role of specific developmental and contextual factors (e.g., acculturation-based intergenerational family conflict and ethnic identity) on depressive and anxiety symptoms and help-seeking attitudes among Chinese American college students. One-hundred and 73 Chinese American college students (132 women and 36 men) from various geographic regions in the U.S. completed a series of questionnaires administered online, assessing acculturation-based intergenerational family conflict, ethnic identity, depressive and anxiety symptoms, and help-seeking attitudes. The findings indicated that the seriousness of acculturation-based intergenerational family conflict and the commitment dimension of ethnic identity were associated with symptoms of depression and anxiety. Additionally, the exploration dimension of ethnic identity was associated with less favorable attitudes toward seeking help from mental health professionals. There was no association between acculturation-based intergenerational family conflict and help-seeking attitudes. The findings underscore the importance of developing culturally informed interventions that attend to the intensity of family conflict and one's sense of connection to ethnic community in the college context. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
A Window into the World of KAM Theory

What happens when you periodically force a nonlinear oscillator in the absence of damping? For linear oscillators, such as the mass-on-a-spring model typically encountered in that first differentia...
Treatment of Couples Experiencing Pregnancy Loss: Reauthoring Loss from a Narrative Perspective

Pregnancy loss is a traumatic event that affects many families. 1 in 5 pregnancies end in miscarriage, and 1–2 out of every 100 births are stillbirths. Mothers report depression, shame, and guilt f...
UAV Airframe Topology Optimization

The development of advanced UAV airframes is currently one of the challenges for the aeronautical industry. An accurate mechanical-structural design analysis provides optimal design solutions. A structural optimization process includes the selection of geometry via topological optimization, the selection of materials by finite element method, and the study of the processes related to the main structures of a UAV. A robust and lightweight UAV airframe allows increasing the flight time and the carrying capacity of the system. This paper deals with the topology optimization of an airframe for an unnamed aerial vehicle (UAV) type quadcopter. The material selection process of the UAV airframe has been achieved through CES Edupack database, taking into account the function, objectives, constraints, free variables, and other considerations during the process of structural optimization. The structural-mechanical optimization of the UAV airframe has been performed using a generative design algorithm through SolidWorks topology optimization method. Also, an estimation of the carrying capacity of the UAV airframe has been realized analytically.
Formulation and Characterization of Microcapsules Encapsulating PC12 Cells as a Prospective Treatment Approach for Parkinson’s Disease

Parkinson’s disease (PD) is the second most common neurological disorder, associated with decreased dopamine levels in the brain. The goal of this study was to assess the potential of a regenerative medicine-based cell therapy approach to increase dopamine levels. In this study, we used rat adrenal pheochromocytoma (PC12) cells that can produce, store, and secrete dopamine. These cells were microencapsulated in the selectively permeable polymer membrane to protect them from immune responses. For fabrication of the microcapsules, we used a modified Buchi spray dryer B-190 that allows for fast manufacturing of microcapsules and is industrially scalable. Size optimization of the microcapsules was performed by systematically varying key parameters of the spraying device. The short- and long-term stabilities of the microcapsules were assessed. In the in vitro study, the cells were found viable for a period of 30 days. Selective permeability of the microcapsules was confirmed via dopamine release assay and micro BCA protein assay. We found that the microcapsules were permeable to the small molecules including dopamine and were impermeable to the large molecules like BSA. Thus, they can provide the protection to the encapsulated cells from the immune cells. Griess’s assay confirmed the non-immunogenicity of the microcapsules. These results demonstrate the effective fabrication of microcapsules encapsulating cells using an industrially scalable device. The microcapsules were stable, and the cells were viable inside the microcapsules and were found to release dopamine. Thus, these microcapsules have the potential to serve as the alternative or complementary treatment approach for PD.
On Semantic Cognition, Inductive Generalization, and Language Models.

My doctoral research focuses on understanding semantic knowledge in neural network models trained solely to predict natural language (referred to as language models, or LMs), by drawing on insights from the study of concepts and categories grounded in cognitive science. I propose a framework inspired by 'inductive reasoning,' a phenomenon that sheds light on how humans utilize background knowledge to make inductive leaps and generalize from new pieces of information about concepts and their properties. Drawing from experiments that study inductive reasoning, I propose to analyze semantic inductive generalization in LMs using phenomena observed in human-induction literature, investigate inductive behavior on tasks such as implicit reasoning and emergent feature recognition, and analyze and relate induction dynamics to the learned conceptual representation space.
Commercial Relations: From Adam Smith to Field Experiments

While seeing both costs and benefits of markets, Adam Smith promotes free markets not only on efficiency but also on moral grounds. Commerce is intertwined with morals, it supports moral development and at the same time it is supported by it. For Smith, commercial societies generate wealth which supports life for an increasing number of people, institutions which support liberty, and social conditions which facilitate moral impartiality. Recent findings from experimental economics seem to support Smith’s ideas that markets and some aspects of morality are dependent on each other, and in particular that the causal effects of the relationship seem to go from markets to morality.
Poly peak parser: Method and software for identification of unknown indels using sanger sequencing of polymerase chain reaction products

Background: Genome editing techniques, including ZFN, TALEN, and CRISPR, have created a need to rapidly screen many F1 individuals to identify carriers of indels and determine the sequences of the mutations. Current techniques require multiple clones of the targeted region to be sequenced for each individual, which is inefficient when many individuals must be analyzed. Direct Sanger sequencing of a polymerase chain reaction (PCR) amplified region surrounding the target site is efficient, but Sanger sequencing genomes heterozygous for an indel results in a string of “double peaks” due to the mismatched region. Results: To facilitate indel identification, we developed an online tool called Poly Peak Parser (available at http://yost.genetics.utah.edu/software.php) that is able to separate chromatogram data containing ambiguous base calls into wild-type and mutant allele sequences. This tool allows the nature of the indel to be determined from a single sequencing run per individual performed directly on a PCR product spanning the targeted site, without cloning. Conclusions: The method and algorithm described here facilitate rapid identification and sequence characterization of heterozygous mutant carriers generated by genome editing. Although designed for screening F1 individuals, this tool can also be used to identify heterozygous indels in many contexts. Developmental Dynamics 243:1632–1636, 2014. © 2014 The Authors. Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists
Parallel composition of templates for tail-energized planar hopping

We have built a 4DOF tailed monoped that hops along a boom permitting free sagittal plane motion. This underactuated platform is powered by a hip motor that adjusts leg touchdown angle in flight and balance in stance, along with a tail motor that adjusts body shape in flight and drives energy into the passive leg shank spring during stance. The motor control signals arise from the application in parallel of four simple, completely decoupled 1DOF feedback laws that provably stabilize in isolation four corresponding 1DOF abstract reference plants. Each of these abstract 1DOF closed loop dynamics represents some simple but crucial specific component of the locomotion task at hand. We present a partial proof of correctness for this parallel composition of “template” reference systems along with data from the physical platform suggesting these templates are “anchored” as evidenced by the correspondence of their characteristic motions with a suitably transformed image of traces from the physical platform.
Ladle Metallurgy Kinetics: Inclusion-Inclusion Reactions

An example is presented to illustrate the joint effect of local reaction equilibria and mass transfer limitations, for reactions during ladle refining of steel. The example relies on some of the kinetic principles that David Robertson has employed to quantify many metallurgical processes. In calcium treatment of alumina inclusions in aluminum-killed steels, solid CaS forms as an intermediate reaction product. During subsequent reaction, CaS disappears and calcium aluminate forms; at the same time, aluminum and sulfur dissolve in the steel. Kinetic analysis shows that the rate of this reaction is not limited by mass transfer of dissolved aluminum and sulfur away from the reacting inclusions. The reaction rate is likely limited by transport of dissolved calcium. This example also illustrates the use of FactSage macros for kinetic modeling.
Unimportance of counterflux in the energetics of "downhill" transport.

Adam Kepes suggested that the cellular transport and hydrolysis of orthonitrophenyl-β-d-galactopyranoside is powered by the counterflux of the d-galactose resulting from β-galactosidase action within the cell. His explanation would rationalize the unique insensitivity of this galactoside transport to energy poisons such as azide. But contrary to the predictions of this hypothesis, (i) there is no initial large inhibition that progressively lessens as galactose is produced. This was shown with a double wavelength stopped-flow spectrophotometer developed to eliminate interference from turbidity transients. (ii) The azide sensitivity does not increase with an external concentration of galactose sufficient to reverse the thermodynamic gradient. (iii) Mutation in galactose utilization or growth on highly catabolite-repressing regimens did not increase the azide sensitivity, and induction of galactose transport and metabolism did not decrease azide sensitivity. It was found that Kepes measurements must have contained two artifacts. One is that the control rate of hydrolysis decreases with time as the dense cell suspension becomes anaerobic. The other is that azide causes turbidity changes for some time after its introduction. If the former is avoided by magnetic stirring and the latter by double wavelength spectrophotometry or controls without substrate, the inhibition is constant from the earliest time that can be measured. It is therefore concluded that energy-unstarved cells, exposed to azide, still have adequate energy reserves to couple to the downhill transport, although their potential is not adequate to drive accumulation against a concentration gradient.
Brain natriuretic peptide: interaction with renal ANP system.

Brain natriuretic peptide (BNP) has recently been found in porcine brain and has been shown to cause diuresis and natriuresis when injected in rats, effects similar to those caused by atrial natriuretic peptide (ANP). BNP is also synthesized in the cardiac atria and circulates in plasma. The amino acid sequence of the peptide resembles that of ANP particularly closely within the ring structure of the peptide. We examined the potential role of BNP in modulating renal function by assessing its ability to mimic the effects of ANP on rat glomeruli and in rabbit inner medullary collecting duct cells (IMCD). BNP bound with high affinity to glomeruli (Kd approximately 900 pM) and IMCD cells (Kd approximately 500 pM). In IMCD cells, BNP stimulated particulate guanylate cyclase (approximately 3-fold at maximum ligand concentration) and inhibited conductive 22Na+ uptake by 50% at concentrations at which ANP is also effective. In rat glomeruli, BNP bound with high affinity to the low-molecular-weight receptors but w...
Correlation between the a relaxation and the excess wing for polychlorinated biphenyls and glycerol

Data are presented for three glass formers, each having an excess wing in the low temperature dielectric loss spectra. Two polychlorinated biphenyls, whose α relaxations have equivalent temperature dependences, exhibit excess wings that are clearly different. Comparison of the spectra for glycerol at atmospheric pressure and at P=0.9 GPa reveals a different response of the α relaxation and the excess wing. These findings cannot be reconciled with the notion that the excess wing is an inherent part of the α relaxation. Interpretation of the spectra as a superposition of distinct α and β processes, however, is consistent with the observed behavior.
A Note on Brief Intimate Encounters

Social work, as a profession, survives by reflecting community values. Because community values seldom recognize the basic needs reflected in short-term relationships, social workers may desire to correct this value imbalance. A defense of the short-term relationship is presented, as well as a comment on its human potential in certain situations.
Computational analysis of adaptive antigenic mutations of the human influenza hemagglutinin for vaccine strain selection

The adaptive evolution of the hemagglutinin (HA) segment of the human influenza H1N1 and H3N2 viruses is not well understood due to antigenic mutations under selection pressures. This paper identified significant antigenic selection sites and discussed the structural relevance of these mutations. We discovered four positively selected sites for H1N1 (position 206 for the 1A lineage  2009 swine influenza, and positions 144, 190, and 192 for the 1B lineage), and eight positively selected sites for H3N2 with the loop regions near residues 157 and 225 as the latest antigenic mutations, which may be targeted for vaccine development.
Ultrastructural organization of GABA-like immunoreactive profiles in the weaver substantia nigra.

GABA-like immunoreactivity (GABA-LI) in the substantia nigra pars compacta (SNc) of mutant weaver mice was investigated at the electron microscope level. Eight-week-old homozygous mutant weaver mice, paired with wildtype littermates as controls, were perfused with a buffered paraformadehyde/acrolein solution. Sections containing the SN were immunocytochemically reacted with an antiserum to GABA using the peroxidase-antiperoxidase (PAP) procedure. Ultrastructural examination revealed that profiles of GABA-LI dendrites were decreased in number while profiles of labeled axonal processes were increased. In addition, there were an increased number of GABA-LI terminals in contact with similarly labeled GABA-LI dendrites. Double-labeling experiments using the antibodies to GABA and dopamine D2 receptors showed that a small number of GABA-LI profiles exhibited D2-like immunoreactivity in both controls and weavers. These results suggest that the GABA-LI synaptic connections are altered as a result of the loss of DA neurons in the SNc of the weaver mice.
Cyclosporine A attenuates mitochondrial permeability transition and improves mitochondrial respiratory function in cardiomyocytes isolated from dogs with heart failure

We used isolated cardiomyocytes to investigate a possible role of mitochondrial permeability transition pore in mitochondrial abnormalities associated with heart failure. Cardiomyocytes were isolated from LV myocardium of normal control dogs and dogs with heart failure produced by intracoronary microembolizations. Mitochondrial permeability transition was measured in isolated cardiomyocytes with intact sarcolemma with and without 0.2 microM cyclosporin A using calcein AM and the fluorometer. State-3 mitochondrial respiration was also measured with the Clark electrode. Mitochondrial membrane potential was measured with JC-1 probe using the fluorometer. Propidium iodide was used to ensure sarcolemma integrity. 200 min after loading with calcein AM, mitochondria of failing cardiomyocytes showed only 50% of maximal level of calcein fluorescence while it remained unchanged in normal cells. The mitochondrial membrane potential in failing cardiomyocytes was significantly decreased by 38% compared to normal cardiomyocytes. Cyclosporine A significantly slowed the exit of calcein from mitochondria of failing cardiomyocytes and increased mitochondrial membrane potential by 29%. State-3 respiration was not affected with cyclosporine A in normal cardiomyocytes while it was significantly increased in failing cardiomyocytes by 20%. Exit of calcein (m.w. 1.0 kDa) from mitochondria of viable failing cardiomyocytes with intact sarcolemma suggests an existence of a reversible transitory permeability transition opening in high conductance mode. Attenuation of calcein exit, DeltaPsi(m) and improvement of state-3 respiration achieved with CsA (0.2 microM) show that permeability transition opening could be a cause of mitochondrial dysfunction described in the failing heart.
Neurotrophin-Induced Migration and Neuronal Differentiation of Multipotent Astrocytic Stem Cells In Vitro

Hypoxic ischemic encephalopathy (HIE) affects 2–3 per 1000 full-term neonates. Up to 75% of newborns with severe HIE die or have severe neurological handicaps. Stem cell therapy offers the potential to replace HIE-damaged cells and enhances the autoregeneration process. Our laboratory implanted Multipotent Astrocytic Stem Cells (MASCs) into a neonatal rat model of hypoxia-ischemia (HI) and demonstrated that MASCs move to areas of injury in the cortex and hippocampus. However, only a small proportion of the implanted MASCs differentiated into neurons. MASCs injected into control pups did not move into the cortex or differentiate into neurons. We do not know the mechanism by which the MASCs moved from the site of injection to the injured cortex. We found neurotrophins present after the hypoxic-ischemic milieu and hypothesized that neurotrophins could enhance the migration and differentiation of MASCs. Using a Boyden chamber device, we demonstrated that neurotrophins potentiate the in vitro migration of stem cells. NGF, GDNF, BDNF and NT-3 increased stem cell migration when compared to a chemokinesis control. Also, MASCs had increased differentiation toward neuronal phenotypes when these neurotrophins were added to MASC culture tissue. Due to this finding, we believed neurotrophins could guide migration and differentiation of stem cell transplants after brain injury.
Structural and spectroscopic characterization of a charge-separated uranium benzophenone ketyl radical complex.

The reaction of [((t-BuArO)3tacn)UIII] (1) with 4,4′-di-tert-butylbenzophenone affords a unique isolable U(IV) ketyl radical species [((t-BuArO)3tacn)UIV(OC•t-BuPh2)] (2) supported by XRD data, magnetization measurements, and DFT calculations. Isolation and full characterization of the corresponding diphenyl methoxide complex [((t-BuArO)3tacn)UIV(OCHt-BuPh2)] (3) is also presented. The one-electron reduction of benzophenone by [((AdArO)3tacn)UIII] (4) leads to a purple U(IV) ketyl radical intermediate [((AdArO)3tacn)UIV(OC•Ph2)] (5). This species is highly reactive, and attempts at isolation were unsuccessful and resulted in methoxide complex [((AdArO)3tacn)UIV(OCHPh2)] (6) from H abstraction and dinuclear para-coupled complex [((AdArO)3tacn)UIV(OCPhPh—CPh2O)UIV((AdArO)3tacn)] (7).
Reply: Values, Ethics, and Geographic Research

(1998). Reply: Values, Ethics, and Geographic Research. Annals of the Association of American Geographers: Vol. 88, No. 2, pp. 308-310.
A double-masked, randomized, placebo-controlled trial of temporary endoscopic mucosal gastric electrical stimulation for gastroparesis

Background Endoscopically placed, temporary gastric electrical stimulation (tGES) may relieve symptoms of gastroparesis (Gp) and predict permanent gastric electrical stimulation (GES) outcomes. Objective To measure effects of 72 hours of temporary GES on Gp symptoms. Design, Setting, and Patients From 2005 to 2006, we conducted a hospital-based, randomized, placebo-controlled, crossover trial of two consecutive, 4-day sessions (session 1 and session 2), enrolling 58 patients (11 males, 47 females; mean age 46 years) with GP symptom histories of three etiologies (idiopathic, 38; diabetes mellitus, 13; postsurgical, 7). Intervention 72 continuous hours temporary GES was provided for group A during session 1, and for group B during session 2. Main Outcome Measurements Symptoms measured daily; gastric emptying, electrogastrography, and quality of life measured at baseline and session close. Results In session 1, vomiting decreased in both groups, but was greater with stimulation, resulting in a day 3 difference of −1.02 (95% CI, −1.62 to −0.42; P P = .005). In session 2, vomiting slightly decreased with stimulation and slightly increased without it; at day 8, the nonactivated group had nonsignificantly greater vomiting, 0.12 (−0.68 to 0.92; P = .762). An overall treatment effect of a slight, nonsignificant daily decrease in average vomiting scores, −0.12 (−0.26 to 0.03; P = .116), was observed by pooling stimulation effects across sessions. Limitations Missing data; potential physiological imbalances between groups. Conclusions Although overall treatment effects were not significant, differences in favor of stimulation were suggested. Barriers to observing treatment effects included a decrease in vomiting for both groups during session 1, insufficient washout, and the absence of baseline vomiting for some patients. Future studies should better define inclusion criteria, use longer washout periods, randomize by etiology and baseline physiological findings, and pursue alternative designs. (Clinical trial registration number: 00432835.)
The Wages of Aging: Time‐Related Determinants of Earnings in the Southern Textile Industry*

The author distinguishes three time-related worker characteristics: physical facility, skill, and firm attachment. In an analysis of wage determination for a sample of textile production workers physical facility and firm attachment, but not skill, had significant curvilinear effects, These, along with exogenous effects of gender and race and endogenous effects of assignments to machine maintenance and to a weave room, are interpreted as reflecting power relations in the contemporary context of the southern textile labor process and labor market. The analysis emphasizes the critical importance of contextual considerations in operationalization, specification, and interpretation for wage determination studies.
A new molecular electronic emission spectrum observed in the reaction of F2 with CS2

Abstract A novel emission spectrum extending from 5500 to 8600 A has been observed during the gas-phase reaction of F 2 with CS 2 . Long progressions in the lower-state (presumably the ground-state) bending frequency and shorter progressions in a ground-state stretching frequency were observed. A partial vibrational analysis is reported, from which two new frequencies are obtained: v ″ 2 = 356 ± 5 and v ″ 3 = 8 31 ± 8 cm −1 .The electronic origin lies near 18500 ± 1200 cm −1 . The spectrum is tentatively assigned to the FCS radical.
Inhibition of accelerated coronary atherosclerosis with dehydroepiandrosterone in the heterotopic rabbit model of cardiac transplantation.

BACKGROUNDAccelerated coronary atherosclerosis has become a critical problem in cardiac transplantation. Although the pathogenesis of this disease is unknown, hypercholesterolemia has been shown to be a major risk factor.METHODS AND RESULTSTo study this problem, a hypercholesterolemic rabbit model of heterotopic cardiac transplantation was developed to study accelerated graft atherosclerosis. Based on suggestions in the literature, it was hypothesized that dehydroepiandrosterone (DHEA) may retard the progression of the disease. Using semiquantitative light microscopy, a predilection for the development of small vessel occlusive disease in the transplanted hearts was found. Chronic DHEA administration produced a 45% reduction in the number of significantly stenosed vessels in the transplanted hearts (p < 0.05) compared with controls and a 62% reduction in the nontransplanted hearts (p < 0.05), yielding an overall 50% reduction in the number of significantly stenosed vessels in both the transplanted and non...
Population genetic structure and natal philopatry in the widespread North American bat Myotis lucifugus

Abstract Molecular genetics tools have been used recently to investigate aspects of bat biology, including the degree of male- and female-driven gene flow among populations. However, none of this work has focused on the little brown bat (Myotis lucifugus), one of the most common bats in North America. Previous work using mark–recapture suggests that like many mammals, including other temperate vespertilionid bats, gene flow in this species is largely driven by males, whereas females return to the roosts in which they were born to rear pups. To determine if this species displays a pattern of population genetic structure that is consistent with this hypothesis I sampled 182 female M. lucifugus at 12 maternity colonies throughout Minnesota. Using a portion of the mitochondrial gene cytochrome b and 10 polymorphic nuclear microsatellites, I found significant structure among colonies, and population differentiation was slightly higher for the mitochondrial locus. This supports the hypothesis that female M. luc...
A geometric presentation for the adjoint module of SL3(k)

Abstract Let k be a field. The points and lines of the projective plane P k 3 determine corresponding subspaces in the space of 3 × 3 traceless matrices (the adjoint module for the group SL 3 ( k )); we show that these subspaces conversely determine the module as their direct limit, modulo derivations of the field k .
Construction of a yeast mutant lacking the mitochondrial nuclease

The nuclear gene from Saccharomyces cerevisiae that encodes the major mitochondrial nuclease was cloned. Gene sequences were identified from a lambda gt11 library by antibodies specific to the mitochondrial nuclease. DNA from the phage recombinant was used to isolate the entire nuclease gene from a plasmid library. Yeast strains containing the nuclease gene on a multicopy plasmid vector overproduced mitochondrial nuclease 20-40 times relative to a wild-type strain. Strains containing a null allele of the nuclease gene lacked all traces of mitochondrial nuclease. Both cell types, however, were phenotypically wild-type indicating that the nuclease is not an essential enzyme for mitochondrial function. The locus encoding the mitochondrial nuclease is termed NUC1.
Burning, watering, litter quality and time effects on N, P, and K uptake by pitch pine (Pinus rigida) seedlings in a greenhouse study

Abstract Young pitch pine seedlings are frequently subjected to prescribed burns in the New Jersey pine barrens as part of the management to eliminate fuel load in these forests, thereby reducing the risk of wildfire. The burns are relatively cool and release nutrients without killing the vegetation. Not all nutrients mineralized are immediately available to the plants, however. To determine factors that may contribute to nutrient release and to link this to availability of nutrients to plants following a fire in the pine barrens, a greenhouse study was conducted. The experimental design was a 3×2×2×3 factorial with three types of litter, high and low watering regime, burned and unburned litter, and three sample dates. Nitrogen, phosphorus, and potassium (through a rubidium analog) uptake rates were measured using natural isotope or radioisotope root bioassays. Though in the short time the experiment ran, neither an overall burned litter nor a litter quality effect was seen, high watering made P less available and K more available. N and K were the most available immediately following application of treatments, whereas P was not available until after 6 weeks following treatment application. Net mineralization of nitrogen, phosphorus, and potassium occurred in burned litter, whereas net immobilization of N and P occurred in highly watered, unburned litter. Since watering and timing were most influential in making nutrients available to seedlings following application of treatments in this greenhouse study, these factors may also be important in making nutrients available to mature trees in the New Jersey pine barrens.
Endoscopic Fetal Tracheal Occlusion: Evolution of Techniques

ABSTRACT Extensive experimental and clinical work has supported a rapid evolution of endoscopic equipment and minimally invasive techniques to successfully perform a variety of fetal surgical inter...