cssi/SciSciGPT-SciSciNet huggingface dataset:
Risk Factors, Mortality & Cost Analysis of Sinusoidal Obstructive Syndrome in Pediatric Hematopoietic Stem Cell Transplant Recipients: A Multi-Institutional Review

Background: Sinusoidal obstructive syndrome (SOS) is a life-threatening complication of hematopoietic stem cell transplant (HSCT) characterized by hepatomegaly, jaundice, weight gain, and hyperbilirubinemia. SOS can be associated with prolonged hospitalizations and significantly increased health care costs in HSCT patients. However, studies evaluating the healthcare burden associated with SOS are limited. In this study we used a large inpatient Pediatric Health Information System database (PHIS) to complete a comprehensive review of pediatric patients undergoing HSCT to identify risk factors for SOS development and morbidity, mortality and healthcare resource utilization associated with this complication. Methods: PHIS is an administrative database containing data from 49 US children’s hospitals. We identified patients under 21 years admitted between 01/01/2016 - 12/30/2019 with a primary or secondary ICD-10 diagnosis of SOS and procedure code for HSCT. We collected the following: 1) Demographics: age, sex, race, geographic location; 2) Length of stay (LOS); 3) ICU admission; 4) Infections; 5) Graft-versus-host disease (GVHD); 6) Mortality; 7) Hospitalization costs; 8) Hospital resource utilization; and 9) Medications including defibrotide use. Differences in outcomes between patients with and without SOS were assessed by Chi-square tests or Wilcoxon nonparametric test for categorical and continuous variables respectively. Univariate and multivariate regression models were used to identify risk factors associated with SOS and the association of SOS on outcomes. P-values Results: In 6,153 patients undergoing HSCT 263 patients (4.3%) experienced SOS. Median age at diagnosis was 5 years and males represented 60.8% of patients with SOS. The majority of patients experiencing SOS identified as white, though patients identifying as Asian or American Indian disproportionately experienced SOS. Allogeneic HSCT represented 81.75% of patients with SOS. Patient age, gender and race were not associated with significantly increased odds of SOS, the odds of SOS were 3 times greater in patients undergoing allogeneic transplantation (OR 3.0, 95% CI 2.2-4.1). Average LOS was significantly higher in patients diagnosed with SOS (71 days vs 43 days, p Conclusions: In this largest inpatient cohort of pediatric HSCT recipients to date, morbidity and healthcare resource utilization remain high among patients who experience SOS. This stresses the importance of early recognition and treatment of SOS, and the importance of novel therapeutic approaches to decrease the morbidity and improve quality of life in these patients. Disclosures No relevant conflicts of interest to declare.
State of the Journal, 2020

Throughout this challenging year, the American Journal of Occupational Therapy (AJOT) has stayed committed to publishing high-quality research so that occupational therapy professionals can make informed decisions about best practice. As we look to the future with a new Editor-in-Chief, our goals are to remain the leading journal for our profession while enhancing our engagement with readers, improving our review process, and ensuring that a diverse group of reviewers and associate editors are able to assume leadership positions with the journal.
Immune escape mechanism of B-cell malignancies on Anti-CD19 Chimeric Antigen Receptor T-cell treatment and solution

Relapse or refractory B-cell malignancies have been reported in multiple clinical trials after treatment of Anti-CD19 Chimeric Antigen Receptor (CAR) T-cells. Many clinical studies have demonstrated the potential immune escape mechanism for B-cell malignancies like genetic mutation, transcriptional deregulation, lineage switch, loss of CAR T-cells, and trogocytosis. The study of these mechanisms can provide us insights in designs of future immunotherapies regarding both B-cell malignancies and even other solid tumors. The potential solution for the immune escape mechanisms regarding CAR T-cell treatment is engineering multispecific CARs. In this article, I review most of the upto- date immune escape mechanism studies and some multispecific CAR T-cell treatment clinical studies and trials that may prevent the escape route and have to potential to cure B-cell malignancies.
Using a News Article to Convey Climate Science Consensus Information

The current study investigates how people respond to a climate science consensus statement embedded within a news article. Participants (N = 1,048) were randomly assigned to read a news article abo...
Increasing social support for women with postpartum depression through attribution theory guided vignettes and video messages: The understudied role of effort

Abstract Guided by Weiner's attribution theory of help-giving, two experimental studies assessed whether emphasizing the temporary nature of postpartum depression (PPD; i.e., stability), the uncontrollable development of the ailment (i.e., onset controllability), and whether it appears someone is making an effort to overcome PPD—a form of offset controllability—would result in changes in anger, sympathy, and social support outcome expectations (SSOEs), and indirectly influence willingness to provide support. Participants were randomly assigned to one of eight conditions focused on the stability and controllability (onset and offset) of PPD, resulting in a 2 × 2 × 2 design. Study 1 used written vignettes and compared each attribution construct to its polar opposite (e.g., temporary vs. permanent). Many of the Study 1 hypotheses were supported, but the interactions offered minimal explanatory value. Study 2 used video messages that either did or did not explicitly mention each attribution construct. Study 2 results indicated that a message focused on the temporary nature of PPD increased SSOEs and was indirectly associated with willingness to provide support. A message focused on effort increased sympathy and by extension willingness to provide support. The onset controllability message had no significant effects in Study 2. The interaction of the different attribution constructs were not significant. Results indicate that offset controllability, operationalized as effort, the extent to which a situation is temporary, and the influence of SSOEs, might be underutilized in both theoretical and applied research.
Molecular Dynamics Simulations Identify Tractable Lead-like Phenyl-Piperazine Scaffolds as eIF4A1 ATP-competitive Inhibitors

eIF4A1 is an ATP-dependent RNA helicase whose overexpression and activity have been tightly linked to oncogenesis in a number of malignancies. An understanding of the complex kinetics and conformational changes of this translational enzyme is necessary to map out all targetable binding sites and develop novel, chemically tractable inhibitors. We herein present a comprehensive quantitative analysis of eIF4A1 conformational changes using protein-ligand docking, homology modeling, and extended molecular dynamics simulations. Through this, we report the discovery of a novel, biochemically active phenyl-piperazine pharmacophore, which is predicted to target the ATP-binding site and may serve as the starting point for medicinal chemistry optimization efforts. This is the first such report of an ATP-competitive inhibitor for eiF4A1, which is predicted to bind in the nucleotide cleft. Our novel interdisciplinary pipeline serves as a framework for future drug discovery efforts for targeting eiF4A1 and other proteins with complex kinetics.
Research on Maximum Power Point Tracking Control of Wind-Solar Hybrid Generation System

This article briefly analyzes the technical advantages of the wind-solar hybrid power generation system, builds models of wind power generation systems, photovoltaic systems, and storage batteries, focusing on the key to wind and photovoltaic power generation systems-maximum power point tracking (MPPT) control, and detailed analysis of the maximum wind and solar power. In order to improve the stability of the wind and solar hybrid power generation system after being connected to the grid. For its grid-connected inverter. A control strategy is proposed: segmented control and improved double closed-loop proportional integral (Proportion Integration, PI). That is to segment according to the strength of the scenery. Adopt the dual structure control of the outer ring of fan speed-the inner ring of fan current and the outer ring of DC boost circuit voltage-the inner ring of grid-connected current. In order to weaken the influence on the frequency and amplitude of the grid. First analyze the mathematical models of wind power generation, photovoltaic power generation, and storage batteries. Then build a complementary power generation system and propose a control strategy. Finally, the simulation is verified by simulation software. The simulation results show that the proposed control strategy can effectively achieve stable operation. For different periods after the wind and solar hybrid power generation system is connected to the grid. Reduce the fluctuation of grid-connected current and maintain the stability of voltage and current. Increase the power grid's ability to absorb new energy.
Massive transfusion and severe blood shortages: establishing and implementing predictors of futility.

Summary Massive transfusion protocols were developed to deliver blood for life-threatening haemorrhage; however, there are no guidelines to advise when massive transfusion protocols may be considered futile. Early recognition of clinical futility remains a challenge as studies have not identified variables that can accurately determine early mortality. As blood is a scarce resource, efforts to distribute it equitably to all patients who would benefit are of paramount importance. In this editorial we discuss recent data and various aspects important in developing and implementing tools that assist with determining futility in massive transfusion.
Effects of Marplan on Catecholamine and Serotonin Metabolism in the Human

Publisher Summary This chapter reports the effects of daily ingestion of Marplan upon catecholamines (CA), 5-hydroxytryptamine (5-HT), and their metabolites. Within the first few hours after ingesting the Marplan, the 5-hydroxyindoleacetic acid (5-HIAA) excretion was decreased, a subjective impairment of sustained attentiveness was noted, critical flicker fusion was impaired, and disjunctive auditory reaction time improved. The latter may be due to the decreased awareness of extraneous stimuli and the increased ability to attend to pertinent stimuli. The first 24-h urine showed a 40% decrease in 5-HIAA and a 54% increase in normetanephrine (MOCA). These indicate a very rapid action, a secondary decrease in CA excretion, and extremely prolonged effects after discontinuing the drug. The chapter attempts to correlate simultaneous measurements of the parent amines as well as their respective intermediates and metabolites, 3-methoxy-4-hydroxymandelic acid (MOMA), the methoxycatecholamines, metanephrine and MOCA, and 5-HIAA.
Lethal Synthesis of Methylglyoxal by Escherichia coli During Unregulated Glycerol Metabolism

In Escherichia coli K-12, the conversion of glycerol to triose phosphate is regulated by two types of control mechanism: the rate of synthesis of glycerol kinase and the feedback inhibition of its activity by fructose-1,6-diphosphate. A strain which has lost both control mechanisms by successive mutations, resulting in the constitutive synthesis of a glycerol kinase no longer sensitive to feedback inhibition, can produce a bactericidal factor from glycerol. This toxic factor has been identified by chemical and enzymological tests as methylglyoxal. Methylglyoxal can be derived from dihydroxyacetone phosphate through the action of an enzyme which is present at high constitutive levels in the extracts of the mutant as well as that of the wild-type strain. Nine spontaneous mutants resistant to 1 mm exogenous methylglyoxal have been isolated. In all cases the resistance is associated with increased levels of a glutathione-dependent enzymatic activity for the removal of methylglyoxal. Methylglyoxal-resistant mutants derived from the glycerol-sensitive parental strain also became immune to glycerol.
A mathematical model of rat proximal tubule and loop of Henle (1137.9)

PT and LOH function are coupled, with proximal transport determining loop fluid composition, and loop transport modulating glomerular filtration via tubuloglomerular feedback (TGF). To examine this...
Application of a plasma lens to e γ colliders

Abstract We describe the focusing of a charged particle beam by a plasma and its application to e γ colliders. After reviewing the issues involved in the final focus and interaction point design for e γ colliders we compare the luminosities for e γ colliders in different scenarios. Using a plasma lens to defocus the spent beam is shown to yield higher luminosity than deflecting the beam with a bending magnet. The possibility of configuring the NLC (Next Linear Collider), and the SLC (Stanford Linear Collider) as e γ colliders is considered together with the physics motivations. It is shown that only with a strong lens , like a plasma lens, is it possible to achieve the desired luminosity.
Black Swans, Gray Cygnets and Other Rare Birds

Surprising, exceptional cases -- so-called black swans -- can provoke extraordinary change in the way we do things or conceptualize the world. While it is not unreasonable to be surprised by a black swan, to be surprised by subsequent cases that are similar enough that they might cause the same sort of upheaval is unforgivable. The problem is how to reason about these almost novel, not totally unforeseen, subsequent cases that I call gray cygnets.
Performance improvement in wireless system due to parallel interference cancellation (PIC) algorithm

Direct sequence code-division multiple access (DS-CDMA) schemes improve system capacity and provide integrated wireless services which include voice, data and video communications. Multiuser detection (MUD), a scheme by which the receiver jointly and simultaneously detects all the signals from the users, provides significant improvement in the capacity of the DS-CDMA system. The paper focuses on subtractive interference cancellation detectors, especially PIC detectors, and compares their performance with that of the matched filter detector. Single user and multiuser detection techniques are discussed including optimal and sub-optimal multiuser detectors.
Virus-induced alterations of lymphoid tissue. IV. The effect of Newcastle disease virus on the fate of transfused thoracic duct lymphocytes.

Abstract 51 Cr-labeled thoracic duct lymphocytes were briefly incubated at 4 °C with Newcastle disease virus (NDV) and then infused into syngeneic rats. Virus diverted the homing of many donor cells from lymph nodes and spleen to the liver. Evidence was obtained suggesting that some NDV-treated lymphocytes initially trapped in the liver subsequently migrated into the lymph nodes. The results imply that NDV transiently interrupts the normal route of lymphocyte migration. Alterations in lymphocyte distribution were mediated by attachment of virus to the cell surface and were the same as those induced by incubating lymphocytes with V. cholera neuraminidase before infusion. It appears that reactions involving 2–3′ and/or2–8′ linked sialyl residues on the surface of recirculating lymphocytes can markedly affect their distribution in the body.
Rottlerin inhibits insulin-stimulated glucose transport in 3T3-L1 adipocytes by uncoupling mitochondrial oxidative phosphorylation.

There is increasing evidence that protein kinase C (PKC) isoforms modulate insulin-signaling pathways in both positive and negative ways. Recent reports have indicated that the novel PKC mediates some of insulin’s actions in muscle and liver cells. Many studies use the specific inhibitor rottlerin to demonstrate the involvement of PKC. In this study, we investigated whether PKC might play a role in 3T3-L1 adipocytes. We found that PKC is highly expressed in mouse adipose tissue and increased on 3T3-L1 adipocyte differentiation, and insulin-stimulated glucose transport is blocked by rottlerin. The phosphorylation state and activity of PKC are not altered by insulin, but the protein translocates to membranes following insulin treatment. In contrast to the results with rottlerin, inhibition of PKC activity or expression has no effect on glucose transport in adipocytes, unlike muscle cells. Lastly, we found that rottlerin lowers adenosine triphosphate levels in 3T3-L1 cells by acting as a mitochondrial uncoupler, and this is responsible for the observed inhibition of glucose transport. (Endocrinology 143: 3884 –3896, 2002)
Static active‐matrix OLED display without pixel refresh enabled by amorphous‐silicon non‐volatile memory

— An active-matrix organic light-emitting-diode (AMOLED) display which does not require pixel refresh is demonstrated. This was achieved by replacing the thin-film transistor (TFT) that drives the OLED with a non-volatile memory TFT, in a 2-transistor pixel circuit. The threshold voltage of the non-volatile-memory TFT can be changed by applying programming voltage pulses to the gate electrode. This approach eliminates the need for storage capacitors, increases the pixel fill factor, and potentially reduces power consumption. Each pixel can be individually programmed or erased using a standard active-matrix addressing scheme. The programmed image is stored in the display even if power is turned off.
Quasi one-dimensional non-passing self-diffusion

Anomalous diffusion of fluids in a restricted geometry which forbids passing of one fluid particle by another has been studied for many years. The detailed dependence of the mobility factor of the single-file diffusion on relevant parameters beyond the strictly one-dimensional limit is not well understood. In this paper, we study the mobility factor of single-file diffusion fluids interacting with a hard potential in two-dimensional pores. We present a rationale for a theory of the dynamic mobility in terms of the equilibrium equation of state, and make preliminary comparison with Monte Carlo simulations of hard discs in a channel.
Inhibition of methotrexate-induced chromosomal damage by vanillin and chlorophyllin in V79 cells†

Methotrexate (MTX), a chemotherapeutic agent used to treat cancer, produces cytogenetic damage and has a cytostatic effect in a variety of test systems. Several antigenotoxic agents have been studied in various in vitro and in vivo systems. However, data are limited regarding their ability to modulate MTX-induced genotoxicity. In the present study, vanillin (VA) and chlorophyllin (CHL) were used as antigenotoxic agents to study their ability to minimize the DNA damage caused by MTX. Exponentially growing V79 Chinese hamster lung cells were treated with MTX at five different concentrations (5–100 μg/ml) with S9 activation for 6 h and post-treated with two concentrations of either VA (50 or 100 μg/ml) or CHL (50 or 100 μg/ml) for 40 h. Cytochalasin B was added for the micronucleus (MN) assay along with antigenotoxic agents to evaluate MN in binucleated cells. Chromosomal aberrations were also evaluated in parallel cultures. Results indicate that MTX alone induced a dose-dependent decrease in the nuclear division index (NDI) and the mitotic index (MI). A significant increase in percent micronucleated binucleated cells (MNBN) and percent aberrant cells (Abs) was observed. Studies using VA as an antigenotoxic agent showed a decrease in the number of MNBN (26.3–83.1%) and Abs (16.0–87.5%) with the addition of either 50 or 100 μg VA/ml. The addition of CHL also significantly reduced the number of MNBN (53.0–91.5%) at both concentrations tested. Chromosomal aberrations were also significantly reduced (41.0–83.0). These studies indicate that both VA and CHL are capable of effectively minimizing MTX-induced chromosomal damage. Teratogenesis Carcinog. Mutagen. 17:313–326, 1997/98. © 1998 Wiley-Liss, Inc.
Chunking away task-switch costs: a test of the chunk-point hypothesis

Previous research has revealed that task-switch costs (worse performance for task switches than for task repetitions) at the first position of an explicit task sequence are eliminated or reduced when repeating or switching sequences. The authors hypothesize that such effects are restricted to points in the sequence representation that are associated with sequence-level processing such as chunk retrieval that changes the contents of working memory. In an experiment testing this chunk-point hypothesis, subjects memorized and performed explicit task sequences under different chunking instructions that induced chunk points at different positions within the sequences. Regardless of position, performance was slower at chunk points than at non-chunk points, providing direct evidence of chunking, and task-switch costs were reduced or eliminated at chunk points while they remained large and robust at non-chunk points. These findings support the chunk-point hypothesis and are discussed in relation to task-set inhibition and associative interference.
Basic proteins in the human aortic intima: nonequilibrium two-dimensional electrophoretic analysis of tissue extracts

Abstract The protein composition of atheroma-free human thoracic intima was compared with that containing fatty streaks or fibro-fatty lesions utilizing two-dimensional gel electrophoresis (2-DE) and silver staining. Intimal proteins extracted with 9 M urea were separated by nonequilibrium pH gradient electrophoresis (NEPHGE) followed by polyacrylamide gel electrophoresis (PAGE) in the second dimension. NEPHGE-PAGE of proteins extracted from atheroma-free intima revealed several major proteins: actin, tropomyosin-like proteins, proteins with relative molecular weight ( M r ) of 250,000 (P 250 ), two proteins with M r about 15,000 (P 15a , P 15b ), and many medium proteins such as a myosin heavy chain, two myosin light chains, and proteins P 47 , P 44 , P 32 , P 27 , P 20a , P 20b , P 19a , P 19b . Several additional proteins were observed in intimas with fatty streaks and fibro-fatty lesions. Most of them, such as albumin, transferrin, Apo A-1, α 1 -antitrypsin, fibrinogen β-chain, IgG, appear to originate from plasma. Differences in protein composition of intima with fibro-fatty streaks compared with adjacent lesion-free intima varied from case to case and need further study. NEPHGE-PAGE in combination with isoelectric focusing (ISO)-PAGE revealed more intimal proteins in atheroma-free and diseased aortas than either method alone, proteins which might be quantitated, isolated for binding studies, and further evaluated for their potential role in atherogenesis.
Reversible Cerebral Vasoconstriction Syndrome: A Rare Entity in Children Presenting With Thunderclap Headache

Reversible cerebral vasoconstriction syndrome is characterized by a reversible segmental and multifocal vasoconstriction of cerebral arteries, and severe headaches with or without focal neurologic deficits or seizures. A 15-year-old boy presented with thunderclap headache. He had severe hypertension, although his neurologic examination was normal. Initial workup for thunderclap headache to exclude subarachnoid or intracranial hemorrhage, meningitis, pituitary apoplexy, or venous sinus thrombosis was negative. Brain magnetic resonance angiography and cerebral angiography demonstrated bilateral anterior and posterior circulation diffuse, multifocal, vascular irregularities (beading and stenosis) suggestive of underlying vasculopathy or vasculitis. He was started on verapamil. There was complete reversal of the vascular abnormalities in 6 weeks evident by magnetic resonance angiography, with resolution of headache and normalization of blood pressure. Reversible cerebral vasoconstriction syndrome has been rarely reported in children. This case report highlights the diagnostic dilemma and management of the rare childhood presentation of this condition.
The development of a cell-substrate attachment system in a euglenoid flagellate.

The transition of the euglenoid Colacium libellae from the free-swimming flagellated to the nonflagellated stage attached by a stalk occurs in three distinct stages: (1) initial attachment, perhaps by the flagellum, (2) substrage contact by the anterior region of the cell concomitant with attachment disc formation, and (3) the extrusion of stalk material. The flagellum is resorbed within minutes of initial attachment. Polysaccharide and acid phosphatase derived from within intracellular cisternae initially accumulate in the reservoir, then transfer to the canal and finally become incorporated into the stalk, thus delineating the source and routte of transport for most stalk material. Indeed, the inner “shaft” and central “core” of the stalk contain a neutral polysaccharide that is continuous with similar material found in the reservoir and canal. The peripheral region of the stalk (the “cortex”), however, contains a polyanionic polysaccharide which may be extruded by a special secretory system composed of a ring of granules and canals located beneth the anterior pellicle of the organism.
Survival and cell death in cells constitutively unable to synthesize glutathione

Abstract We examined the role of GSH in survival and cell death using GCS-2 cells that are deficient in glutamate cysteine ligase (γ-glutamyl cysteine synthetase, γGCS), an enzyme essential for GSH synthesis. Cells maintained in 2.5 mM GSH have GSH levels that are ∼2% of wild type and grow indefinitely; however, they express both pro- and anti-apoptotic Bcl-2 family members and have detectable levels of cytoplasmic cytochrome C. Withdrawal of GSH from the medium results in a fall in intracellular GSH to undetectable levels, decreased mitochondrial dehydrogenase activity, decreased anti-apoptotic factor RNAs, increased pro-apoptoic factor RNAs, additional cytochrome C release, and a fall in ATP levels; however, cells continue to grow for another 24 h. At 48 h, these trends continue with the exception that mitochondrial membrane potential and ATP levels rise; DNA fragmentation begins at 48 h. Thus, severe reduction of GSH to 2% of wild type produces a metastable state compatible with survival, but complete absence of GSH triggers apoptosis.
Characterization of affinity-labeled fluorescyl ligand to specifically-purified rabbit IgG antibodies

Abstract Fluorescein isothiocyanate was reacted with purified rabbit anti-fluorescyl IgG antibodies under defined conditions. Relative to the normal IgG control, significantly more ligand was conjugated to the purified antibody which was then inhibited from further binding with radioactively labeled ligand (3H-N-acetylfluorescein amine). Fluorescyl ligand conjugated to purified antibody preparations exhibited a red spectral shift characteristic of specifically bound fluorophore. Fluorescence of ligand conjugated to antibody was quenched about 95% relative to ~ 90% for ligand reversibly bound. The quantum yield (Φ) of the former is indicative of a thiocarbamyl linkage within the antibody-active site. Fluorescence lifetime (t) measurements by phase and modulation showed a close correlation between liganded and affinity-labeled antibody relative to free ligand and fluorescyl conjugated non-antibody proteins. The fluorescyl-affinity label was not dissociated from the antibody-active site upon denaturation of the protein in 6M guanidine-HCl. Reduction, alkylation and resolution of H and L chains in two different dispersing agents showed that the ligand remained attached to either chain. Fluorescyl ligand bound to high affinity IgG (i.e. non-affinity labeled) was quantitatively released under conditions required for H and L chain production. The fluorescence of affinity labeled ligand was enhanced in high concentrations of deuterium oxide. The latter is characteristic of ligand bound specifically to the antibody active site and is not observed with fluorescein covalently conjugated to non-specific Ig.
Asset Preservation in African Agriculture in the Face of HIV/AIDS: The Role of Education

HIV/AIDS degrades the assets of African farm families. The epidemic erodes the family's resources (time, human capital, physical capital, and finances), fragments their social and economic networks, and undermines their organizational capacities. To counteract these adverse impacts, farm families would benefit from assistance that replenishes their assets, modifies their activities, reorganizes their work routines, revives their support networks, and provides access to new knowledge. HIV/AIDS-affected farm families, however, face a Catch 22. With an eroding asset base, they are losing the capacities to craft and sustain the necessary changes. Education, both formal and non-formal, is an external intervention that would help farm families offset the effects of HIV/AIDS. Education enables family members to enhance their knowledge, augment their skills, and take advantage of new information about production, consumption, and welfare-enhancing opportunities. This article argues that education and learning, if selectively and sensitively provided, would help farm families preserve their assets in the face of HIV/AIDS.
Ionization of aqueous toluic acids: Conductance and thermodynamics

Conductivities of aqueous solutions ofortho-, meta-, andpara-toluic acids have been measured for the concentration range 0.1–2 millimolar and at 5° intervals from 5 to 100°C. At each temperature pKa(m) andA0 have been calculated using the paired ion model recently described by Fuoss. Thermodynamic parameters have been calculated for the ionization of each acid, and Walden products for the anions. Results are discussed in terms of contributions to acidity by enthalpy and entropy changes as well as by hydration of the various solute species.
Signal validation with control-room information-processing computers

Abstract One of the ‘lessons learned’ from the Three Mile Island accident focuses upon the need for a validated source of plant-status information in the control room. The utilization of computer-generated graphics to display the readings of the major plant instrumentation has introduced the capability of validating signals prior to their presentation to the reactor operations staff. The current operations philosophies allow the operator a quick look at the gauges to form an impression of the fraction of full scale as the basis for knowledge of the current plant conditions. After the introduction of a computer-based information-display system such as the Safety Parameter Display System (SPDS), operational decisions can be based upon precise knowledge of the parameters that define the operation of the reactor and auxiliary systems. The principal impact of this system on the operator will be to remove the continuing concern for the validity of the instruments which provide the information that governs the operator's decisions.
Secondary late components of the muscarinic postsynaptic potentials, in rabbit superior cervical ganglion

Abstract The well known muscarinic slow excitatory polysynaptic potential (s-EPSP) of rabbit superior cervical ganglion (SCG) peaking at about 1–2 s and lasting 5–10 s, is immediately followed by an abrupt change in slope to a longer, lower depolarizing phase. A brief dip in the level of depolarization (DP) often separates the two depolarizing phases. The secondary phase of s-EPSP rises to its own peak at about 25 s; total duration 60–120 s. With repetition of orthodromic volleys secondary s-EPSP builds up more gradually than initial s-EPSP, but more rapidly than slow-slow (ss-) EPSP. The later ‘secondary’ depolarizing phase along with the antecedent ‘dip in DP’ are, like the ‘initial’ s-EPSP, eliminated by a muscarinic antagonist, quinuclinidyl benzilate hydrochloride (QNB). This distinguishes secondary s-EPSP from the even slower rising non-cholinergic ss-EPSP. The ss-EPSP, although relatively small in the responses to the usual 3-pulse test stimuli, rises to an extraordinary amplitude (equal to the compound action potential) during a 10 s–120 s train of pulses. Gallamine blocked most of the slow IPSP component in test responses but not initial or secondary s-EPSP. A preganglionic conditioning train (10/s for 2 min) induced a long-term-enhancement (LTE) of secondary s-EPSP lasting > 3 h, with maximum postconditioning percentage increases greater than for initial s-EPSP. Also enhanced was the dip in DP, now forming a deeper notch between initial and secondary s-EPSPs; this attains a maximum at about 30 min postconditioning but thereafter progressively loses the enhancement by about 90 min. The dip in DP appears to represent some delayed, perhaps hyperpolarizing process that may overlap with the initial and secondary phases of s-EPSP and affect their forms and peak amplitudes. This would not exclude the possibility that the initial and secondary phases of s-EPSP reflect multiple muscarinically activated electrogenic mechanisms having differing time-courses.
On the meaning of sink capture efficiency and sink strength for point defects

Abstract The concepts of sink capture efficiency and sink strength for point defects are central to the theory of point defect reactions in materials undergoing irradiation. Two fundamentally different definitions of the capture efficiency are in current use. The essential difference can be stated simply. The conventional meaning denotes a measure of the loss rate of point defects to sinks per unit mean point defect concentration. A second definition of capture efficiency, introduced recently, gives a measure of the point defect loss rate without normalization to the mean point defect concentration. The relationship between the two capture efficiencies is here derived. By stating the relationship we hope to eliminate confusion caused by comparisons of the two types of capture efficiencies at face value and to provide a method of obtaining one from the other. Internally consistent usage of either of the capture efficiencies leads to the same results for the calculation of measuable quantities, as is required physically.
Pedagogical Content Knowledge: From a Mathematical Case to a Modified Conception

Eight fifth-grade teachers were interviewed about their teaching of equivalence of fractions. Analysis of the interviews resulted in a conception of pedagogical content knowledge consisting of four...
Basin evolution, thermal history and hydrocarbon potential of the St. George Basin, Bering Sea, Alaska : a comparative study using one- and two-dimensional models

Abstract The hydrocarbon potential of the St. George Basin, Alaska, was evaluated using both one- and two-dimensional basin models. Whereas the St. George Basin was probably cooler in the past, the sensitivity of the results to uncertainties in lithology, depth to basement, depth to formation tops, and palaeo-water depth, suggests that a range of heat flow histories is the appropriate way to model the hydrocarbon potential. On the margins of the basin, the models predict that small amounts of hydrocarbons have been generated from Eocene and Early Oligocene sediments starting at about 37.0 million years before present (MYBP) (high paleeo-heat flux) or at 5.0 MYBP (cool palaeo-heat flux). In the deepest part of the St. George Basin, the models predict that the pre-Pliocene sediments have generated hydrocarbons from at least 24.0 MYBP. At both locations the different heat flow scenarios affect the predicted timing of hydrocarbon generation but not the age of the sediments which generate hydrocarbons nor the amount of hydrocarbons accumulated. A regional seismic line, which intersects the COST 1 well, was depth converted and ‘drilled’ by regularly spaced pseudo-wells from which a cross-section was constructed. Modelling the cross-section using a two-dimensional model predicted the same results as those obtained from the one-dimensional model, indicating that a one-dimensional approach was sufficient to approximate this section. Both models predict a negligible accumulation of hydrocarbons at COST 1, i.e. COST 1 is a dry well. A synthesis of modelled results and qualitative information indicates that the St. George Basin has a very low potential for hydrocarbon accumulation. On the basin margin the limited source quality and lack of seals result in a low accumulation of any generated hydrocarbons. Hydrocarbons generated elsewhere in the basin may be lost vertically or trapped within the graben in difficult to identify traps. Overall the St. George Basin is an unattractive exploration target.
A note on the computation of the outflow derivative for singular perturbation problems

A method for computing the outflow derivative of singular perturbation problems is derived. The method essentially involves integrating the differential equation numerically, and numerical experiments indicate the technique is very accurate when the problem is convection dominated.
Transcription of the nonrepeated fraction of “accessible” DNA in rat liver chromatin.

The relationship between structure and function in eukaryotic chromatin has been studied in rat liver cells. To elucidate the functional significance of "accessible" DNA, the transcription of this DNA (prepared by titration of liver chromatin with poly-D-lysine) has been examined by RNA-DNA hybridization. The maximum extent to which nuclear RNA will hybridize to the nonrepeated fraction of "accessible" DNA has been measured and compared to the extent that whole chromatin DNA will hybridize. The results show that "accessible" DNA has the same number of sequences complementary to nuclear RNA as does total DNA. In addition DNA-DNA reassociation experiments indicate that there is only a small difference between the total unique sequence populations of "accessible" and total DNA. These results indicate that nonrepeated "accessible" DNA is not preferentially transcribed in the cell as is predicted by some models of chromatin structure.
Post‐conflict Social Events in Wild Mountain Gorillas. II. Redirection, Side Direction, and Consolation

Inevitably, members of primate groups sometimes have aggressive contests with each other. Targets of aggression can engage in several types of interaction with third parties to ameliorate its adverse effects. They can redirect aggression, which may reduce the risk of further aggression from the initial opponents and reduce tension, or they can initiate affinitive interactions with third parties, in order to seek protection or reassurance. They can also receive reassuring acts from them (‘consolation’). Researchers have documented high levels of redirection in many primate species, but consolation is thus far known only in chimpanzees. Data on post-conflict social interactions between targets of aggression and third parties in two groups of wild mountain gorillas (Gorilla gorilla beringei) show that immatures and subordinate males, but not females, redirect aggression at high rates. Furthermore, immatures seek affinitive interactions with their mothers, and adult females seek them with adult males, at elevated rates. Affinitive interactions between females and males seem mainly to have a protective function and are associated with decreased risks of further aggression between female opponents. Redirection by females after female-female conflicts may be uncommon because targets commonly retaliate against aggressors. Males may offer females protection and consolation as services, and the results support the argument that such services are important when dominance relationships between females are often undecided and retaliation between opponents is common.
Fabrication of high Tc superconducting films with diffusion barriers

Superconducting YBa 2 Cu 3 O; thin films have been prepared by magnetron sputtering onto [100] single crystal MgO with and without an Au buffer layer. All samples show high transition temperatures (82–87 K). The use of an Au buffer layer significantly improves the superconducting properties, particularly the Meissner effect and critical current density (3.3×10 6 A/cm 2 at 2 K and 3.5×10 4 A/cm 2 at T=77 K). The Au buffer layers remain metallic after high temperature annealing in an oxygen atmosphere, and may thus serve as effective current shunts.
Towards a microscopic understanding of the phonon bottleneck

The problem of the phonon bottleneck in the relaxation of two-level systems (spins) to a narrow group of resonant phonons via emission-absorption processes is investigated from first principles. It is shown that the kinetic approach based on the Pauli master equation is invalid because of the narrow distribution of the phonons exchanging their energy with the spins. This results in a long-memory effect that can be best taken into account by introducing an additional dynamical variable corresponding to the nondiagonal matrix elements responsible for spin-phonon correlation. The resulting system of dynamical equations describes the phonon-bottleneck plateau in the spin excitation, as well as a gap in the spin-phonon spectrum, for any finite concentration of spins. On the other hand, it does not accurately render the line shape of emitted phonons and still needs improving.
High-resolution acoustic measurements in fluids and gases by a path length modulation technique

An acoustic technique has been developed that permits high-resolution velocity measurements to be performed in liquids and gases under circumstances where the acoustic attenuation may become very large. This cavity resonance method has been demonstrated in cavities with lengths as small as 150 µm at acoustic frequencies up to 151 MHz. The acoustic path length is continuously adjusted by a piezoelectric bimorph controlled by feedback from a sensitive acoustic impedance spectrometer. The measurement of velocity then simply reduces to measurement of position of the bimorph, and this can be performed with high accuracy using a capacitance bridge. Absolute measurements of the attenuation of sound can also be performed with this arrangement. It is suggested that this approach will be useful for the study of collective excitations in quantum fluids.
Locomotor activity and anorexogenic action

A method is described with which it is possible to measure locomotor activity and food intake simultaneously in the same rat or other small animal. From a study of a number of psychomotorstimulant drugs and anorectic agents it may be concluded that locomotorstimulation and appetite-suppression are two different effects that may or may not characterize the same drug. Methamphetamine and phenmetrazine are stimulants in doses that do not inhibit food intake. Amphepramon reduced food intake in low doses but acts as a stimulant in higher doses. Chlorphemternine and phenfluramine are anorectic agents that are not stimulants, even in high doses.
Bispectral analysis of a fluid elastic system: The cantilevered pipe

Abstract Bispectra of the vibrations of a cantilevered pipe conveying fluid are calculated from numerical integrations of the equations of motion. Previous experimental and theoretical work has shown that for certain parameter ranges the vibrations follow a period-doubling route to chaos. Bispectral analysis isolates the nonlinear phase coupling and energy exchange between Fourier components of the vibrating pipe. As flow through the nonlinear stiffened pipe increases, phase-coupled harmonics of the power-spectral primary frequency grow. For parameters close to those associated with chaotic vibrations, subharmonics become phase-coupled to the primary frequency. Cross-bispectra indicate that both sum and difference interactions result in nonlinear phase coupling and energy exchange between the modes of pipe vibration.
Structures detected in a stable, high-voltage spark discharge by time-resolved Schlieren spectroscopy

Abstract Experimental results are presented of time- and spatially-resolved Schlieren studies on the formation of an atmospheric pressure, positionally-stabilized, spark discharge. Results are documented at repetition rates extending into the kHz region for a pulsed, unidirectional discharge sampling current. Included are details of an initial kernel appearing early in time from which shock waves emerge at times correlative to changes in the spark current waveform. Also detailed is the formation of a unique post-discharge toroidal structure located about the interelectrode axis long after the discharge current has ceased. These features have not evidenced themselves previously in direct observation of emitted light. Discussion of present interpretation of these phenomena is included.
Cerebral metabolic effects of organophosphorus anticholinesterase compounds.

Rats treated intravenously with an organophosphoras anticholinesterase compound, paraoxon or soman, were sacrificed 2 to 131 min later, using 0.7sec of focused microwave irradiation (25 kW at 915 MHz). Brain regional rates of glucose utilization during 3-min intervals were determined with labeled glucose and fluorodeoxyglucase as tracers. Levels of glucose, lactate, ATP, and creatine phosphate were assayed in the same samples. The two compounds differed markedly in their effects on brain metabolism. Paraoxon (0.8LD50) depressed rates of glucose use in all brain regions, without causing consistent changes in brain metabolite levels. This depressant effect was most pronounced during the first 30 min after toxin exposure and had largely disappeared by 2hr. Soman (0.8–0.95 LD50) was variable in its effects. Animals that showed seizure-like behavior had marked increases in glucose use in diencephalon and cerebrum but no changes in cerebellum or brain stem. Rapid rates of glucose use were associated with high levels of lactic acid and lower levels of creatine phosphate. In cerebrum, but not diencephalon, levels of ATP fell by as much as 50% in strongly affected animals by 30–130 min after soman. All of these effects were reversible with atropine. Soman-treated animals that did not have seizure-like activity did not exhibit these brain metabolic changes. These results and those of others show that cholinergic compounds vary greatly in their effects on brain glucose and energy metabolism. Although noncholinergic mechanisms are a possibility, the most parsimonious explanation for these findings is that cholinesterase inhibitors vary in their affinity for different central nervous system (CNS) acetylcholine receptor populations.
Intercostal hernia and spontaneous pneumothorax in a liver transplant recipient: a case report

Intercostal hernia can occur after blunt trauma and can also complicate thoracotomy. This report describes a 13-year-old liver transplant recipient with chronic asymptomatic intercostal hernia at site of thoracotomy. This hernia became manifest upon development of spontaneous pneumothorax. She presented with pleuritic pain and radiographic evidence of spontaneous pneumothorax. Her history included liver transplantation at age 19 months for tyrosinemia, posttransplant lymphoproliferative disorder at age 7 years with thoracotomy for lung biopsy, and prolonged corticosteroid administration. Examination and computed tomography revealed an intercostal hernia. She underwent repair of hernia, stapled resection of apical blebs, and pleurodesis. Reconstruction of chest wall involved rib fracture and intercostal approximation with nonabsorbable sutures covered by serratus muscle advancement. She is symptom free with intact repair 2 years and 9 months after surgery and is able to participate in vigorous physical activity. This is the first report of an intercostal hernia detected upon development of spontaneous pneumothorax. The hernia occurred at the site of a prior thoracotomy, possibly because of impaired healing from corticosteroid administration. This case suggests that nonabsorbable sutures should be used for intercostal approximation after thoracotomy in patients with impaired wound healing.