cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluation of triproline and tri-α-methylproline chiral stationary phases: Retention and enantioseparation associated with hydrogen bonding

In this study, to demonstrate preparation strategy and improve understanding of chiral recognition mechanisms, triproline chiral stationary phases (CSPs) were evaluated with a series of analytes classified as having none, one, two or three H-bond donors. The average retention factors and mobile phase strength generally followed none<one<two<three hydrogen bond donors. The average solvent volume ratio (H(r) stands for average hexane volume ratio in the mobile phase, Hp(r) for heptane, ACN(r) for acetonitrile, or H(2)O(r) for water) normalized chromatographic parameters calculated for di-, tri-, tetra-, penta-, hexa-, and decaproline CSPs facilitated the characterization of properties associated to the H-bond donor categorization. The H(r) of triproline CSP were 1.0, 0.96 and 0.88 for analyte of none, one and two hydrogen bond donors with hexane/2-propanol mobile phase, respectively. The number of hydrogen bond donors in an analyte was found to be a primary factor in influencing the retention and enantioseparation in the normal-phase and polar organic modes. Two H-bond acceptor solvents methyl tert-butyl ether and ethyl acetate increased chiral separation on oligoproline CSPs for some compounds. The role of carbon-donor hydrogen bonding at the H atom of proline asymmetric center was implied through testing a tri-alpha-methylproline stationary phase. On oligoproline CSPs, three factors including adjacent hydrogen bond acceptor and carbon-donor, and a rigid proline residue chain were recognized as important for contributing to the broad enantioselectivity. The alpha hydrogen atom on chiral center of stationary phase was found to play a crucial role in enantiomeric discrimination.
Peer Deviance, Social Networks, and Suicide Ideation Intensity in a Clinical Sample of Adolescents

Although research has identified interpersonal difficulties as risk factors for adolescent suicidality, parent and peer relationships are often assessed as discrete risk domains. The current study uses a social network approach to assess individual differences in the degree to which a clinical sample of 129 adolescents being treated for suicidal ideation rely on parents or peers for their attachment needs. Youth who affiliated with deviant peers were more likely to: (a) report greater intensity (increased frequency and duration and decreased controllability) of their suicide ideation, and (b) identify peers rather than adults as attachment figures. Adolescents’ peer relationships are associated with suicide ideation intensity in a clinical sample of suicidal and depressed adolescents.
Partial and radical nephrectomy in children, adolescents, and young adults: Equivalent readmissions and postoperative complications.

Abstract Objectives To compare and contrast the use of partial nephrectomy (PN) and radical nephrectomy (RN) in pediatric malignant renal tumors using a nationally representative database. Methods The 2010–2014 Nationwide Readmissions Database (NRD) was used to obtain PN and RN select postoperative data. ICD-9-CM codes were used to identify children ( Results There were 4330 weighted encounters (1289 PNs, 3041 RNs) that met inclusion criteria: 50.8% were children, 7.2% were adolescents, and 42% were young adults. Young adults had the highest rates of PN, whereas children had the highest rates of RN (p Conclusion There was no evidence of a difference in odds between RN and PN in terms of postoperative readmissions or in-hospital complication rates. Additionally, we observed descriptive differences in both cost and LOS between the surgical modalities across age groups. Type of study Retrospective comparative study (administrative database analysis). Level of evidence Level III.
Everyone Can Be a Star: Understanding the Role of Live Video Streaming in Online Retail

With the rising popularity of live video streaming in recent years, it has begun to attract interest from both e-commerce practitioners and the research community. However, there is scarce academic research in understanding whether and how live video streaming affects the landscape of e-commerce. In this paper, we seek to understand the effects of the adoption of live video streaming strategy by online retailers and their online product sales. Leveraging multiple archival data sources, we combine econometrics with deep learning to test the hypotheses. The results indicate that adopting live video streaming strategy significantly boosts online product sales. Furthermore, we propose a novel deep learning framework to address the challenge of identifying product-oriented live video streaming, and find that the adoption of a product-oriented live video streaming strategy increases online product sales, whereas there is no significant impact for adopting non-product-related live video streaming strategy. In the meanwhile, the impact of product-oriented live videos is attenuated as the buyers’ uncertainty decreases. These results provide empirical support that reduction in product uncertainty via information provision is the main mechanism through which live video streaming increases online sales.
Improved production of 76Br, 77Br and 80mBr via CoSe cyclotron targets and vertical dry distillation.

Abstract Introduction The radioisotopes of bromine are uniquely suitable radiolabels for small molecule theranostic radiopharmaceuticals but are of limited availability due to production challenges. Significantly improved methods were developed for the production and radiochemical isolation of clinical quality 76Br, 77Br, and 80mBr. The radiochemical quality of the radiobromine produced using these methods was tested through the synthesis of a novel 77Br-labeled inhibitor of poly (ADP-ribose) polymerase-1 (PARP-1), a DNA damage response protein. Methods 76Br, 77Br, and 80mBr were produced in high radionuclidic purity via the proton irradiation of novel isotopically-enriched Co76Se, Co77Se, and Co80Se intermetallic targets, respectively. Radiobromine was isolated through thermal chromatographic distillation in a vertical furnace assembly. The 77Br-labeled PARP inhibitor was synthesized via copper-mediated aryl boronic ester radiobromination. Results Cyclotron production yields were 103 ± 10 MBq∙μA−1∙h−1 for 76Br, 88 ± 10 MBq∙μA−1∙h−1 for 80mBr at 16 MeV and 17 ± 1 MBq∙μA−1∙h−1 for 77Br at 13 MeV. Radiobromide isolation yields were 76 ± 11% in a small volume of aqueous solution. The synthesized 77Br-labeled PARP-1 inhibitor had a measured apparent molar activity up to 700 GBq/μmol at end of synthesis. Conclusions A novel selenium alloy target enabled clinical-scale production of 76Br, 77Br, and 80mBr with high apparent molar activities, which was used to for the production of a new 77Br-labeled inhibitor of PARP-1. Advances in knowledge New methods for the cyclotron production and isolation of radiobromine improved the production capacity of 77Br by a factor of three and 76Br by a factor of six compared with previous methods. Implications for patient care Preclinical translational research of 77Br-based Auger electron radiotherapeutics, such as those targeting PARP-1, will require the production of GBq-scale 77Br, which necessitates next-generation, high-yielding, isotopically-enriched cyclotron targets, such as the novel intermetallic Co77Se.
A gatekeeper protein contributes to T3SS2 function via interaction with an ATPase in Vibrio parahaemolyticus.

Abstract Assembly of a functional type III secretion system (T3SS) requires intricate protein-protein interactions in many bacterial species. In Vibrio parahaemolyticus, the leading cause of seafood-associated diarrheal illnesses, the gatekeeper protein VgpA is essential for T3SS2 to secrete its substrates. However, it is unknown if VgpA interacts with other core elements of T3SS2 to mediate its substrate secretion. Through bacterial two-hybrid (BACTH) analysis, we now show that VgpA physically interacts with VscN2 (an ATPase essential for T3SS function) and six other hypothetical proteins. Mutation of isoleucine to alanine at residue 175 of VgpA (VgpAI175A) abolished its ability to interact with VscN2. Importantly, complementation of a VgpA nonsense mutant (vgpA’) with VgpAI175A did not restore the ability of T3SS2 to secrete substrates, demonstrating that VgpA-VscN2 interaction is critical for the function of T3SS2. Bacterial cell fractionation and mass spectrometry analyses showed that vgpA’ resulted in significant alterations of T3SS2 protein abundance in multiple bacterial cell fractions. Particularly, VscN2 abundance in the inner membrane fraction and VscC2 abundance in the outer membrane fraction are significantly reduced in vgpA’ compared to those in WT. These results demonstrated that VgpA contributes to T3SS2 function via its interaction with VscN2 and possibly by affecting subcellular distribution of T3SS2 proteins.
Mortality Implications of Angina and Blood Pressure in Hypertensive Patients With Coronary Artery Disease: New Data From Extended Follow-up of the International Verapamil/Trandolapril Study (INVEST)

Background Angina and hypertension are common in patients with coronary artery disease (CAD); however, the effect on mortality is unclear. We conducted this prespecified analysis of the International Verapamil/Trandolapril Study (INVEST) to assess relationships between angina, blood pressure (BP), and mortality among elderly, hypertensive CAD patients. Hypothesis Angina and elevated BP will be associated with higher mortality. Methods Extended follow-up was performed using the National Death Index for INVEST patients in the United States (n = 16 951). Based on angina history at enrollment and during follow-up visits, patients were divided into groups: persistent angina (n = 7184), new-onset angina (n = 899), resolved angina (n = 4070), and never angina (n = 4798). Blood pressure was evaluated at baseline, during drug titration, and during follow-up on-treatment. On-treatment systolic BP was classified as tightly controlled (<130 mm Hg), controlled (130–139 mm Hg), or uncontrolled (≥140 mm Hg). A Cox proportional hazards model was created adjusting for age, heart failure, diabetes, renal impairment, myocardial infarction, stroke, and smoking. The angina groups and BP control groups were compared using the never-angina group as the reference. Results Only in the persistent-angina group was a significant association with mortality observed, with an apparent protective effect (hazard ratio: 0.82, 95% confidence interval: 0.75-0.89, P < 0.0001). Uncontrolled BP was associated with increased mortality risk (hazard ratio: 1.29, 95% confidence interval: 1.20-1.40, P < 0.0001), as were several other known cardiovascular risk factors. Conclusions In hypertensive CAD patients, persistent angina was associated with lower mortality. The observed effect was small compared with other cardiovascular risk factors, such as BP, which were associated with increased mortality.
Formative evaluation of instructional development

In this paper we have tried to describe the research pertinent to the activity of formative evaluation. While the number of good examples of formative evaluation is expanding, the level of research into the process is relatively limited. Perhaps a compromise to the difficult task of accumulating research data on formative evaluation might be suggested. When formative evaluation activities have been successful in terms of program effects and staff satisfaction, then detailed technical reports might be made available to the evaluation public. Formative evaluation might improve as a consequence of the technology developed in the course of finding solutions to development data problems. Both the increase in technology as a result of dissemination of successful procedures and the pursuit of experimental research on the process of evaluation might ultimately remove formative evaluation recommendations from the realm of seers and clairvoyants and thrust it closer to, if not into, the domain of scientific application.
Spontaneous parametric oscillation based on atomic coherence

Summary form only given. Theoretical and experimental work of past few years on atomic coherence and interference has demonstrated a potential to improve significantly the existing nonlinear optical techniques. In this contribution we present theoretical and experimental results demonstrating the possibility of efficient parametric oscillation in Raman-like double-/spl Delta/ systems. We discuss the possible applications of this process for quantum noise suppression and nonlinear mixing at a very low (few photon) power level.
Estimating Bounds on Expected Plateau Size in MAXSAT Problems

Stochastic local search algorithms can now successfully solve MAXSAT problems with thousands of variables or more. A key to this success is how effectively the search can navigate and escape plateau regions. Furthermore, the solubility of a problem depends on the size and exit density of plateaus, especially those closest to the optimal solution. In this paper we model the plateau phenomenon as a percolation process on hypercube graphs. We develop two models for estimating bounds on the size of plateaus and prove that one is a lower bound and the other an upper bound on the expected size of plateaus at a given level. The models' accuracy is demonstrated on controlled random hypercube landscapes. We apply the models to MAXSAT through analogy to hypercube graphs and by introducing an approach to estimating, through sampling, a key parameter of the models. Using this approach, we assess the accuracy of our bound estimations on uniform random and structured benchmarks. Surprisingly, we find similar trends in accuracy across random and structured problem instances. Less surprisingly, we find a high accuracy on smaller plateaus with systematic divergence as plateaus increase in size.
Marginalized at the center: how public narratives of suffering perpetuate perceptions of refugees’ helplessness and dependency.

This paper critiques the common practice of people from refugee backgrounds giving presentations and testimonials on their displacement experiences, in college, university, and similar institutional settings. While such speaking events may be framed as opportunities to center refugee voices, this paper argues that the totality of the presentation environments, especially their focus on narratives of suffering, do in fact reinforce the marginal and powerless position with which refugees are associated. To counteract the marginalizing effects of such presentations, the paper suggests alternative ways of presentations that more meaningfully involve refugees in framing and directing such speaking events.
Bioelectrical impedance assessment of nutritional status in critically ill patients.

The objective of this study was to assess the utility of bioelectrical impedance analysis (BIA) in determining nutritional status in critically ill patients in the intensive care unit (ICU). Data were collected prospectively in 33 mechanically ventilated medical and surgical ICU patients requiring nutrition as part of their care. BIA, with subsequent calculation of body-composition indexes, was performed every other day for the duration of ICU stay. Body cell mass (BCM) changes correlated with energy and protein intakes (r2 = 0.87, P < 0.001 and r2 = 0.67, P < 0.001, respectively). Maintenance of BCM was achieved by a daily provision of 125.5 kJ.kg-1.d-1 (30 kcal.kg-1.d-1) and 1.5 g protein/kg whereas greater intakes allowed restoration of BCM. The mean ratios of exchangeable sodium to potassium (Nae:Ke) improved only in patients achieving positive nitrogen balance (P = 0.013). Body-composition changes determined by BIA represent a feasible adjunctive method for evaluating and monitoring nutritional status in ICU patients.
Coronary Artery Bypass Occlusion Secondary to Postcardiotomy Syndrome

Abstract Postcardiotomy syndrome following coronary vein bypass procedures may cause graft occlusion as a result of the associated myxedematous hyperemic inflammation that later forms dense obliterative fibrosis. Variability of symptoms and onset make early recognition of postcardiotomy syndrome difficult. However, the presence of the classic triad of fever, chest pain, and pleuropericardial reactions along with leukocytosis and elevated sedimentation rate should suggest the diagnosis. Early recognition and prompt institution of steroid therapy offer relief of symptoms and regression of inflammation and probably reduce the incidence of graft occlusion. From early experience with 14 patients who developed postcardiotomy syndrome and received only symptomatic treatment, 12 developed graft occlusion, whereas in 31 subsequent patients with this syndrome who were treated with steroids, only 5 demonstrated graft occlusion.
Infrared and kinetics study of polymer-bound rhodium cluster catalysts for olefin hydrogenation

Supporting membranes were prepared by copolymerizing, p-bromostyrene, and divinylbenzene; a fraction of the bromine was then replaced with diphenylphosphine groups, and the phosphinated membrane contacted with Rh/sub 6/(CO)/sub 16/. This catalyst hydrogenated cyclohexene to cyclohexane (at low conversion) at 75/sup 0/C and 1 atm with > 99% selectivity in a reaction that was second order in cyclohexene, 0.5 order in hydrogen, and had an apparent activation energy of 7 kcal/mole. The polymer catalysts were active in ethylene hydrogenation in a reaction that was 0.8 order in ethylene, 0.2 order in hydrogen, had an activation energy of 5-6 kcal/mole, and remained stable for 30 hr. The metal clusters had no carbonyl ligands during steady-state cyclohexene hydrogenation, but were apparently bound into the polymer matrix by replacement of some of the carbonyls with bound phosphines. When oxygen was rigorously excluded, no aggregation into rhodium metal crystallites was observed, and the catalyst was stable for up to 75 hr. In contrast to cyclohexene hydrogenation, ethylene hydrogenation proceeded in the presence of only partially decarbonylated polymer catalyst.
Protein-protein interactions in calcium transport regulation probed by saturation transfer electron paramagnetic resonance.

We have used electron paramagnetic resonance (EPR) to probe the homo- and heterooligomeric interactions of reconstituted sarcoplasmic reticulum Ca-ATPase (SERCA) and its regulator phospholamban (PLB). SERCA is responsible for restoring calcium to the sarcoplasmic reticulum to allow muscle relaxation, whereas PLB inhibits cardiac SERCA unless phosphorylated at Ser16. To determine whether changes in protein association play essential roles in regulation, we detected the microsecond rotational diffusion of both proteins using saturation transfer EPR. Peptide synthesis was used to create a fully functional and monomeric PLB mutant with a spin label rigidly coupled to the backbone of the transmembrane helix, while SERCA was reacted with a Cys-specific spin label. Saturation transfer EPR revealed that sufficiently high lipid/protein ratios minimized self-association for both proteins. Under these dilute conditions, labeled PLB was substantially immobilized after co-reconstitution with unlabeled SERCA, reflecting their association to form the regulatory complex. Ser16 phosphorylation slightly increased this immobilization. Complementary measurements with labeled SERCA showed no change in mobility after co-reconstitution with unlabeled PLB, regardless of its phosphorylation state. We conclude that phosphorylating monomeric PLB can relieve SERCA inhibition without changes in the oligomeric states of these proteins, indicating a structural rearrangement within the heterodimeric regulatory complex.
A Comment on Maximum Likelihood Estimation for Finite Mixtures of Distributions

Iterative numerical methods are necessary to find the maximum likelihood estimates for finite mixture distributions. This paper shows that it will often be possible to analytically reduce the number of equations that must ultimately be solved numerically. Such a reduction in dimensionality has not generally been used, or sought after, for mixture distributions. Yet such results are easily derived when each mixture component is assumed to be from the same parametric model within the exponential family.
Interference with the function of leukocyte adhesion molecules by monoclonal antibodies: a new approach to burn injury.

Un anticorps monoclonal inhibant la proteine d'adhesion ICAM-1 a ete utilise pour inhiber l'adherence leucocytaire dans deux modeles de brulure. Les anticorps anti ICAM-1 sont efficaces en preservant la microvascularisation et en modulant la reponse systemique a une brulure grave. Ces resultats suggerent le role des leucocytes dans la physiopathologie des brulures
Invalid survey response patterns among middle school students

Student surveys are widely used to assess student risk behavior, bullying, and school climate in middle schools; however, because such surveys are usually conducted on an anonymous basis, little is known about the validity of student reports using external, independent criteria. This longitudinal study examined the response patterns of 382 middle school students who completed confidential (not anonymous) self-report surveys each fall and spring for 3 years of middle school (Grades 6-8). Approximately 10% of students in each wave indicated on validity screening questions that they were either not telling the truth or not paying attention (termed invalid responders). A repeated measures latent class analysis found that students could be classified into a large group (64%) that was never flagged by the validity questions and a smaller group (36%) that occasionally reported not telling the truth or not paying attention. Hierarchical linear modeling analyses found that invalid responding to validity questions was associated with higher self-reported rates of risk behavior and more negative perceptions of school climate. Based on independent criteria from school records, invalid responding students were more likely to be referred for disciplinary infractions than other students. This study provides new information about student survey validity and appears to be the first to identify characteristics of students who generate invalid response patterns.
Manic Thinking Independent Effects of Thought Speed and Thought Content on Mood

This experiment found that the speed of thought affects mood. Thought speed was manipulated via participants' paced reading of statements designed to induce either an elated or a depressed mood. Participants not only experienced more positive mood in response to elation than in response to depression statements, but also experienced an independent increase in positive mood when they had been thinking fast rather than slow--for both elation and depression statements. This effect of thought speed extended beyond mood to other experiences often associated with mania (i.e., feelings of power, feelings of creativity, a heightened sense of energy, and inflated self-esteem or grandiosity).
Normal startle responding in psychosis-prone college students

Abstract Some researchers have predicted that subjects with high scores on questionnaires of psychosis-proneness would show deficiencies in the habituation and prepulse inhibition of the startle reflex, similar to those seen with schizophrenics. In two experiments, startle eyeblink EMG was measured in physical anhedonics, perceptual aberrators, and normal controls. In Experiment 1 ( N = 64), eyeblink amplitude and probability habituated to both 85 and 100 dB SPL acoustic pulses. In Experiment 2 ( N = 48), acoustic prepulses at intensities of 55 or 70 dB SPL were presented with stimulus onset asynchronies (SOAs) of 60 or 120 msec before startle-eliciting stimuli at intensities of 85 and 100 dB SPL. Inhibition of startle was generally more pronounced when the prestimulus was more intense and at a longer SOA, and when the eliciting stimulus was more intense (for response amplitude). In both experiments, startle responses were larger and more probable for more intense eliciting stimuli. Also, the diagnosis group variable had no significant effect in either experiment. These results demonstrate that college students who produce high scores on scales of psychosis-proneness may not provide a good model for the perceptual gating deficits which have been demonstrated in schizophrenic patients, with regard to automatic measures of stimulus processing.
THE SUCCESSIVE OH BINDING ENERGIES OF SC(OH)N+ FOR N = 1-3

The geometries of Sc(OH)n+, for n = 1-3, have been optimized using density functional theory, in conjunction with the B3LYP hybrid functional. The zero-point energies are computed at the same level of theory. The successive OH bond energies have been computed at the CCSD(T) level for ScOH+ and Sc(OH)2+. The computed result for ScOD+ is in excellent agreement with the recent experiment of Armentrout and co-workers. There is a dramatic drop for the third OH, because Sc+ has only two valence electrons and therefore the bonding changes when the third OH is added. The difference between the B3LYP and CCSD(T) OH binding energies for the first two OH groups is discussed.
Provider acceptance, safety, and effectiveness of a computer-based decision tool for colonoscopy preparation.

Abstract Purpose To assess provider acceptance of recommendations by a decision tool that scans the electronic medical record and determines whether sodium phosphate may be taken. In addition, to determine decision tool effects on a composite outcome of colonoscopies canceled, rescheduled, aborted, or repeated sooner than recommended due to preparation (prep) quality; prep quality; colonoscopy duration; and patient satisfaction with and tolerance of the preparation. Methods We used 4 alternating 4-week periods to compare the decision tool with usual care for outpatient colonoscopy. All decision tool decisions were reviewed in real-time by gastroenterology nurses and/or physicians. Patients completed a survey about the prep process. Endoscopists blindly rated prep quality. Colonoscopy duration and findings were recorded. Results Of 354 persons in the decision tool group, 4 prep decisions were overridden because of patient preference or prior prep failure, but none for medical reasons. Sodium phosphate was used more frequently in the decision tool group (73% vs. 41%; P P =0.29), acceptable prep quality (62% vs. 56%; P =0.22), colonoscopy duration (28 vs. 30min; P =0.17), patient satisfaction ( P =0.38), or preparation tolerance ( P =0.37). Conclusions An electronic medical record-based decision tool can safely and effectively tailor the prep for colonoscopy and may improve colonoscopy efficiency and patient satisfaction. Limitations This study was performed at a single VA medical center and endoscopy unit, relies on the presence of relevant medical conditions and laboratory data in the electronic medical record, and had a higher than expected use of sodium phosphate during usual care.
Colorimetric Determination of Acetyl Sulfisoxazole in the Presence of Its Hydrolysis Products, Sulfisoxazole and Acetic Acid

The official assay for acetyl sulfisoxazole, the diazotization method, does not differentiate between acetyl sulfisoxazole and its main hydrolysis product, sulfisoxazole. A spectrophotometric method, involving the formation of ferric acetohydroxamate, was developed, and conditions necessary for reproducible reaction were developed. The method provides a relatively simple and rapid means by which acetyl sulfisoxazole is quantitatively determined in the presence of its main hydrolysis products, sulfisoxazole and acetic acid.
Time-frequency MUSIC

A new method for the estimation of the signal subspace and noise subspace based on time-frequency signal representations is introduced. The proposed approach consists of the joint block-diagonalization (JBD) of a set of spatial time-frequency distribution matrices. Once the signal and noise subspaces are estimated, any subspace based approach, including the multiple signal classification (MUSIC) algorithm, can be applied for direction of arrival (DOA) estimation. Performance of the proposed time-frequency MUSIC (TF-MUSIC) for an impinging chirp signal using three different kernels is numerically evaluated.
Spline matrices and their applications to some higher order methods for boundary

The main purpose of this paper is to introduce and use spline matrices that are symmetric banded matrices whose entries are associated with the B-splines. A fundamental problem is to find estimates of the smallest eigenvalues for some of these matrices. As an application of these results we present two high order discretization methods for the two-point boundary value problem $y'' = f(x,y);y(0) = y_0 ,y(1) = y_1 $, where $f_y \geqq 0$. The first is a four-step method which has an error $\| e \|_\infty \leqq Ch^{{11} / {2}} $. A six-step method is also given with error $\| e \|_\infty \leqq Ch^{{15} / {2}} $. Both results are improvements of classical methods. Computer results are also included.
Position synthesis of the double-rocker mechanism

Abstract Closed-form equations are presented which permit the synthesis of the planar four-bar double-rocker mechanism for coordinating the prescribed extreme positions. The method is well adapted to digital programming for obtaining optimal mechanism design. A numerical example is provided.
Determination of aluminum and silicon in biological materials by inductively coupled plasma atomic emission spectrometry with electrothermal vaporization

Abstract An atomic emission spectrometric method is described for the determination of trace elements in microvolume samples especially of biological materials. Based upon the arrangement of a commercial electrothermal vaporizer and a 40-MHz inductively coupled plasma, the direct determination of aluminum and silicon in human body fluids such as urine and serum and aluminum in hemodialysis solution is performed. The instrumental system involves vaporizing the sample from a modified graphite electrode followed by atomization and excitation of the vapors in the ICP discharge. Compromise experimental conditions are reported and calibration functions compared. Limits of detection in 5-μl samples were 8 pg Al and 2.5 ng Si, and after preconcentration of Al with a poly(acrylamidoxime) resin, the detection limit was 1 pg Al. Recovery of 5 μg Si ml and 10 ng Al ml from aqueous and synthetic standards was 80–85% and 96–103%, respectively.
Determining Ppb Mercury Concentrations Using a Spark-Source Mass Spectrometer Sample Changer

Abstract A probe-type sample changer has been added to a spark-source mass spectrometer enabling the rapid determination of ppb levels of mercury by isotope dilution. The technique has also been used for determining Cd, Hg, and Zr in samples of air, water, and urine.
Polyribonucleotide — Anthraquinone interactions: In vitro antiviral activity studies

Abstract Twelve anthraquinones (AQ) were evaluated for their ability to potentiate the antiviral activity of poly r(A-U) using a human foreskin fibroblast-vesicular stomatitis virus bioassay in which the AQ was combined with 0.2 mM poly r(A-U) to produce an AQ/ribonucleotide ratio of 1/4. Poly r(A-U) and the AQs alone were not effective antiviral agents. Five of the twelve AQs tested, mitoxantrone, adriamycin, ametantrone, carminic acid and daunomycin, enhanced the antiviral activity of poly r(A-U) 9- to 13-fold. The interferon-inducing activity of the five active AQ/poly r(A-U) combinations was equal to the sum of the interferon-inducing activities of their constituents. These five AQs appear to potentiate the antiviral activity of poly r(A-U) without superinduction of interferon.
Interactions between agmatine and polyamine uptake pathways in rat pulmonary artery endothelial cells

Agmatine, a product of arginine metabolism in vascular endothelial cells, is structurally similar to the natural polyamines, putrescine, spermidine and spermine. To test the hypothesis that agmatine and polyamines interacted at the level of the polyamine transporter, we determined if polyamines competed with agmatine for import and whether interventions modulating polyamine import exerted coordinate effects on agmatine uptake. Multiple lines of evidence were obtained to suggest that agmatine enters pulmonary artery endothelial cells (PAECs) via the polyamine transporter, though its intracellular disposition after uptake appears different from the natural polyamines.
The effects of aggregation on the lethality of phencyclidine in mice

The lethal effects of d-amphetamine and phencyclidine (PCP) were compared when adult male mice were placed into isolated or aggregated (12 mice/cage) conditions. The LD50 of d-amphetamine decreased approx. 30-fold between isolated (87.9 mg/kg) and aggregated (2.8 mg/kg) conditions. In contrast, PCP showed only a 1.3-fold increase in toxicity between isolated (64.5 mg/kg) and aggregated (48.4 mg/kg) conditions. These results suggest different mechanisms for the acute lethal effects of d-amphetamine and PCP in mice.
Thermoanalytical characterization (DTA and TG) of RBa2Cu3O7-x (R Y, Gd, Nd) superconductors

Differential thermal analysis (DTA) and thermogravimetric (TG) analysis were used to characterize RBa2Cu3O7-x (R  Y, Gd, Nd) superconductors. Even if the resistivity-temperature curves are similar for the three compounds, DTA shows that the behavior of these materials during synthesis and sintering is different. Of the three systems, the Nd-Ba-Cu-O system is the most favorable for the formation of the 123 superconductor because secondary phases are present in smaller quantities. TG curves suggest the presence of a transition from the orthorhombic phase to the tetragonal phase in a nitrogen atmosphere at about 550–600°C for the three perovskites. The energy required to insert oxygen atoms in the crystal structure is smaller for the neodymium and gadolinium compounds than for the yttrium compound (Gd < Nd < Y). There is also a proportional relation between the ionic radius of the rare earth element and the onset melting temperature.
EFFECT OF AN ELECTRIC DIPOLE MOMENT OF THE PROTON ON THE ENERGY LEVELS OF THE HYDROGEN ATOM

The perturbations of the energy levels of the hydrogen atom by a possible electric dipole moment of the proton, $d$, have been obtained. The inhomogeneous equation for the first-order perturbation of the wave functions was solved analytically. The shifts of the energy levels are of the second order in $d$. In particular, there results a decrease of the Lamb shift between the $2{S}_{\frac{1}{2}}$ and $2{P}_{\frac{1}{2}}$ levels. By equating this decrease to the maximum allowed by the approximate agreement between the experimental and theoretical values of the Lamb shift, it is concluded that the electric dipole moment of the proton, $d$, must be less than 1.3\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}13}$ cm times the charge of the electron. Calculations have also been carried out for the shifts of the energy levels of deuterium produced by a possible electric dipole moment of the deuteron.
Group Contribution Values for the Thermodynamic Functions of Hydration at 298.15 K, 0.1 MPa. 2. Aliphatic Thiols, Alkyl Sulfides, and Polysulfides

Group additivity contributions are evaluated for normal and branched thiols (mercaptans), alkyl sulfides, and polysulfides on the basis of a compilation of experimental values of the infinite dilution partial molar Gibbs energy, enthalpy, and heat capacity of hydration, together with molar volumes in aqueous solution at 298.15 K and 0.1 MPa. The thermodynamic data were treated using both first- and second-order group additivity methods. Numerical values of the contributions to each of the thermodynamic properties are obtained for the following first-order S-containing groups: SH, S, S2, and S3 as well as for the C−SH correction for the attachment of the thiol group to the tertiary carbon atom. In the case of the second-order group contribution method, numerical values are determined for the groups C−(S)(H)3, C−(C)(S)(H)2, C−(C)2(S)(H), C−(C)3(S), S−(H)(C), S−(C)2, S−(S)(C), and S−(S)2.
Infrared images of jet impingement

Infrared images of jet impingement are used to evaluate the effectiveness of heat transfer due to an air jet from a nozzle striking a surface. A unique Heat Transfer Jet Impingement Facility (HJIF) has been designed and constructed for testing nozzles. The nozzles to be tested are mounted in the facility. The performance of the nozzles at various flow and operating conditions is evaluated from infrared images and computer codes. The experimental apparatus and the operational procedures for the utilization of the infrared images are described. This unique application of infrared imaging as a research and development tool for determining air nozzle performance at steady state conditions has been found to be generally superior to earlier approaches.
Detection of vanadium by means of spot tests

Zwei neue Tupfelreaktionen fur Vanadinum werden beschrieben.α-Benzoinoxim gibt einen gelben Niederschlag in schwefelsauren Vanadatlosungen, der auf der Tupfelplatte den Nachweis von 1γ Vanadinum ermoglicht. Der Nachweis der durch Zusatz von Vanadylsalz zu Ferrichlorid gebildeten Ferroionen kann auf der Tupfelplatte mitα,α′-Dipyridyl oder mit o-Phenanthrolin durchgefuhrt werden. In beiden Fallen wird eine Erfassungsgrenze von 0,1γ Vanadinum erreicht und nur wenige Ionen storen den Nachweis.
Laparoscopic management of benign cystic teratomas during pregnancy

Abstract OBJECTIVE: Our purpose was to evaluate the surgical management and outcome of laparoscopic removal of benign cystic teratomas during pregnancy. STUDY DESIGN: The records of women with benign cystic teratomas who were managed with operative laparoscopy during pregnancy were reviewed. RESULTS: Twelve women had laparoscopic removal of a benign cystic teratoma during pregnancy. Gestational ages at surgery ranged from 9 to 17 weeks, with a mean of 14 weeks. Cyst size ranged from 5 to 13 cm, with a mean of 8.5 cm. Intraoperative rupture of the cyst occurred in 10 of 12 (93%) women. No patient had evidence of chemical peritonitis. The mean operating time was 87 minutes and the mean postoperative hospital stay was 44 hours. No intraoperative or postoperative maternal or fetal complications occurred. CONCLUSIONS: Laparoscopic removal of a benign cystic teratoma of the ovary may be safely accomplished during pregnancy. In spite of a significant risk of cyst rupture, careful operative technique followed by copious irrigation of the pelvis may avoid chemical peritonitis and potential adverse sequelae. (AM J OBSTET GYNECOL 1996;174:1499-501.)
Going Global in Century XXI: Medical Anthropology and the New Primary Health Care

I argue here that there is a need for medical anthropology to innovate conceptual and methodological tools to work effectively within complex social spaces created by the articulation of the global and the local in the liberal nonstate. The need for such innovation is suggested by a criticism of the local consequences of global neoliberal health reform and consideration of the potential practical health policies that emerge from such a criticism, especially the need for greater “community participation” in health. In this criticism I draw on the example of market-based health reform in postsocialist Mongolia. This example suggests that the applied medical anthropology of the future must be one that integrates across multiple levels of analysis, straddling the local and the global. It should cast a critical eye on local civil society, the local manifestations of global policy, and take an activist orientation to global health advocacy. Anthropologists must become master synthesizers, sensitive to local mea...
Effective approach for strained InAs/GaAs quantum structures

Abstract We model an InAs/GaAs quantum dot (QD) with a single sub-band approach and an energy dependent effective electron mass. Confined states of carriers are formed by the band-gap potential. An additional potential is included in the model to simulate the combined effect of strains and piezoelectricity. It is shown that this effect may be taken into account in an effective manner. The model allows us to reproduce the results of ab initio calculations. To prove the adequacy of our model, we compare the results obtained for energy spectra of few electrons, tunneling into InAs/GaAs QD, with experimental capacitance–gate-voltage data. The non-parabolic effect taken into account in this calculation is quite visible for QD sizes considered. We discuss the possibility to describe the CV experimental data with electron confinement obtained from realistic model calculations, as well as limitations of these models in the case of extremely small QD size.
Madison’s Tightrope: The Federal Union and the Madisonian Foundations of Legitimate Government

The states’ rights–nationalist debate is America’s oldest constitutional debate. It is also the most puzzling, since it continues to stagger through the scholarly and political landscape even after numerous and powerful assailants—including the Civil War, the 14th Amendment, the New Deal, and the Civil Rights Era—would have seemed to have sealed its doom. Even James Madison, the father of the Constitution and perhaps the most widely respected political thinker among the founding generation, seemed puzzled about the nature of the American federal union for much of his career. This article argues that late in life, Madison elaborated a theory of “layered social compacts” that provides a compelling account of the nature of the American federal union. His account makes a significant contribution to social compact theory and also provides a potentially helpful guide for navigating today’s states’ rights–nationalist debates.
Suppression of yeast ingestion by dexamethasone in macrophage cultures: Evidence for a steroid-induced phagocytosis inhibitory protein

Abstract The mechanism by which glucocorticoid steroids suppress yeast phagocytosis in cultures of resident and thioglycollate-elicited murine peritoneal macrophages was examined. Time course and dose-response studies demonstrated that the phagocytic capacity of resident macrophages was suppressed by dexamethasone to the same extent in both newly established cultures and cultures that were incubated for several days. In contrast, relative to newly established cultures of elicited cells that were treated with the drug, elicited macrophages that were incubated for at least 1 day prior to exposure to dexamethasone, exhibited enhanced sensitivity to the action of the steroid. Steroid-induced phagocytic inhibitory responses were blocked by the metabolic inhibitors cycloheximide and actinomycin D. The suppression of phagocytosis by dexamethasone was mediated by a factor, present in the cellular homogenates of steroid-treated macrophages, that was partially purified by Sephadex G-25 chromatography. Since the phagocytic inhibitory activity in these homogenates was destroyed following exposure to heat and trypsin, the factor has been named phagocytosis inhibitory protein (PIP). The antiphagocytic activity of PIP was neutralized by treatment with RM23, a monoclonal antibody directed against lipocortin. These results support the hypothesis that the suppression of yeast ingestion is mediated by the action of PIP, which is induced in dexamethasone-treated macrophage cultures. Moreover, PIP appears to belong to the lipocortin family of phospholipase inhibitory proteins.
Observation of Dislocations in Ice

The advantages and disadvantages of the three techniques used to examine dislocations in ice, viz., etch pitting−replication, transmission electron microscopy, and X-ray topography (XT), are reviewed, and it is shown that XT is the most useful of these techniques. The introduction of high-intensity synchrotron radiation for XT demonstrated that conventional XT observations are of dislocation structures which have undergone recovery. Some of the important dynamic observations and measurements of dislocations which have been made using synchrotron X-ray topography are outlined.
Clinical and pathological observations in infants with coarctation of the aorta and patent ductus arteriosus

T H E R E are few reports of blood pressure determinations in infants with coarctation of the aorta 1-7 because of the obvious difficulty in using the conventional anscultatory or palpatory techniques for blood pressure measurements in infancy. The " f lush" technique described by one of us 2 has been found to be an easy, reliable procedure for routine blood pressure measurements in infants and has been used for the past four years on the wards at the St. Louis Children's Hospital. This technique has been especially helpful as a screening procedure in suspected cases of coarctation of the aorta. Since such infants are usually desperately ill upon admittance to the hospital, minimal diagnostic procedures can be done. Repeated attempts at auscu]tatory and palpatory blood pressure determinations are usually unsuccessful, but the application of the simple " f lush" technique is easily accomplished. We thought it would be of interest to report the blood pressure findings and other observations in fourteen infants with coarctation of the aorta demonstrated at autopsy. The diagnosis was made ante mortem in all except two cases, and the
Mutagenesis of basic residues R151 and R161 in manganese-stabilizing protein of photosystem II causes inefficient binding of chloride to the oxygen-evolving complex.

Manganese-stabilizing protein of photosystem II, an intrinsically disordered polypeptide, contains a high ratio of charged to hydrophobic amino acid residues. Arg151 and Arg161 are conserved in all known MSP sequences. To examine the role of these basic residues in MSP structure and function, three mutants of spinach MSP, R151G, R151D, and R161G, were produced. Here, we present evidence that replacement of Arg151 or Arg161 yields proteins that have lower PSII binding affinity, and are functionally deficient even though about 2 mol of mutant MSP/mol PSII can be rebound to MSP depleted PSII membranes. R161G reconstitutes O2 evolution activity to 40% of the control, while R151G and R151D reconstitute only 20% of the control activity. Spectroscopic and biochemical techniques fail to detect significant changes in solution structure. More extensive O2 evolution assays revealed that the Mn cluster is stable in samples reconstituted with each mutated MSP, and that all three Arg mutants have the same ability to re...
The experience of knee arthritis in athletic young and middle-aged adults: an heuristic study.

Objective. To gain a better understanding of the experience of living with tibiofemoral osteoarthritis (OA) as young and middle-aged adults. Methods. Heuristic qualitative research methods were used. Four informants between the ages of 25 and 45 years diagnosed with tibiofemoral OA were purposively sampled. Informants were white, college educated, middle class, and physically active. Informants were interviewed for 4 hours. Interviews were transcribed verbatim and analyzed according to a van Kaam method modified by Moustakas. Results. Living with tibiofemoral OA involved pain, fear, isolation, helplessness, and loss of function, identity, and perceived control. The informants struggled with adapting to their pathology. Behavior change and activity modification were difficult and seemed to be related to the physical, sociologic, and psychologic aspects of pathology. Conclusions. A biopsychosocial model of chronic pathology was developed that may guide health professionals in treating and developing interventions for younger adults with arthritis.
Bringing Women's Voice to Research on Women in Management: A Feminist Perspective

Research on women in management has stagnated; major breakthroughs in our knowledge about women are coming from other disciplines. Three differences between the research on women in management and ...