cssi/SciSciGPT-SciSciNet huggingface dataset:
Measurement of electric field uniformity in an electrostatic separator

Electrostatic separators are used in several modern storage rings to generate large distortions of the closed orbit as a means of avoiding undesirable beam-beam collisions in the arcs. Unlike comparable magnetic elements, there is not a well developed technology to measure the electric field quality of electrostatic separators, so the ultimate field uniformity is largely left up to the conservatism and skill of the designers and fabricators of the devices. Measurements of the electric field integrate over the entire path of the particles, including end effects, and sense the effects of misalignments, warpage and other mechanical errors on individual units. This ability not only helps with quality control, but also to interpret machine studies where the results are sensitive to the nonuniformities of the electric field. In particular, electric field measurements can provide a better estimate of the tuneshift and sextupole moments as a function of beam position in the separators.
An Overview of the Fast Auroral Snapshot (FAST) Satellite

The FAST satellite is a highly sophisticated scientific satellite designed to carry out in situ measurements of acceleration physics and related plasma processes associated with the Earth’s aurora. Initiated and conceptualized by scientists at the University of California at Berkeley, this satellite is the second of NASA’s Small Explorer Satellite program designed to carry out small, highly focused, scientific investigations. FAST was launched on August 21, 1996 into a high inclination (83°) elliptical orbit with apogee and perigee altitudes of 4175 km and 350 km, respectively. The spacecraft design was tailored to take high-resolution data samples (or’ snapshots’) only while it crosses the auroral zones, which are latitudinally narrow sectors that encircle the polar regions of the Earth. The scientific instruments include energetic electron and ion electrostatic analyzers, an energetic ion instrument that distinguishes ion mass, and vector DC and wave electric and magnetic field instruments. A state-of-the-art flight computer (or instrument data processing unit) includes programmable processors that trigger the burst data collection when interesting physical phenomena are encountered and stores these data in a 1 Gbit solid-state memory for telemetry to the Earth at later times. The spacecraft incorporates a light, efficient, and highly innovative design, which blends proven sub-system concepts with the overall scientific instrument and mission requirements. The result is a new breed of space physics mission that gathers unprecedented fields and particles observations that are continuous and uninterrupted by spin effects. In this and other ways, the FAST mission represents a dramatic advance over previous auroral satellites. This paper describes the overall FAST mission, including a discussion of the spacecraft design parameters and philosophy, the FAST orbit, instrument and data acquisition systems, and mission operations.
Rat pancreatic nuclear thyroid hormone receptor: characterization and postnatal development.

Abstract To document the presence of 3,5,3′-triiodothyronine nuclear receptor in the rat pancreas, the solubilized pancreatic nuclear fraction was characterized for its binding to 3,5,3′-l-triiodothyronine. Binding was found to be reversible, saturable, and specific. Scatchard analysis revealed a single class of 3,5,3′-l-triiodothyronine receptors in the pancreata of adult rats. The dissociation constant was 0.29 ± 0.02 × 10 −9 M, and maximal binding capacity was 242 ± 10 fmol of T 3 bound per milligram of non-histone protein at 30 °C (n = 20). Both parameters are comparable with those of adult rat liver nuclei. The degree of receptor occupancy was 30%–40% of the total sites in the adult rat pancreas. Developmentally, 3,5,3′-l-triiodothyronine binding was not detectable at birth and very low in pups
Inhibition of Poly(ADP-Ribose) Polymerase Reduction of Ischemic Injury and Attenuation of N-Methyl-d-Aspartate–Induced Neurotransmitter Dysregulation

Background and Purpose—The nuclear enzyme poly(ADP-ribose) polymerase (PARP) may play a role in DNA repair. However, in cerebral ischemia, excessive PARP activation may lead to energy depletion and...
Single molecule real-time sequencing of Xanthomonas oryzae genomes reveals a dynamic structure and complex TAL (transcription activator-like) effector gene relationships.

Pathogen-injected, direct transcriptional activators of host genes, TAL (transcription activator-like) effectors play determinative roles in plant diseases caused by Xanthomonas spp. A large domain of nearly identical, 33–35 aa repeats in each protein mediates DNA recognition. This modularity makes TAL effectors customizable and thus important also in biotechnology. However, the repeats render TAL effector (tal) genes nearly impossible to assemble using next-generation, short reads. Here, we demonstrate that long-read, single molecule real-time (SMRT) sequencing solves this problem. Taking an ensemble approach to first generate local, tal gene contigs, we correctly assembled de novo the genomes of two strains of the rice pathogen X. oryzae completed previously using the Sanger method and even identified errors in those references. Sequencing two more strains revealed a dynamic genome structure and a striking plasticity in tal gene content. Our results pave the way for population-level studies to inform resistance breeding, improve biotechnology and probe TAL effector evolution.
The New French Abortion Pill: The Moral Property of Women

In September 1988 the pharmaceutical firm Hoechst began to market the RU-486 pill in France designed to induce abortion in the early stages of pregnancy. Motivated by anti-abortion activism in France and the US which included boycotting the companys products and threatening officials Hoechst decided to withhold it from both markets. The French Health Minister overruled that action by saying that "in the few weeks that RU-486 had existed it had become the moral property of women." Hoechst continued not to market the pill in the US because the US pharmaceutical market represented a large portion of its earnings. This paper discusses the legal and administrative procedures involved in getting a new drug/product approved in the US. The chapters include: 1) the food and drug administration approval process; 2) RU-486 as a potential contraceptive; 3) RU-486 and existing abortion law Roe v. Wade; 4) home use of RU-486 and the Griswold right to privacy; 5) the possibility of individual state intervention; 6) resistance to and support for Ru-486 in the US. The paper raises the possibility of approving Ru-486 as a contraceptive pill since it could fit within the federal law of abortion defined in Roe v. Wade. While the Supreme Courts decision in Roe did not anticipate that abortion could be performed by other methods besides surgery chemical abortion by RU-486 could be consistent with the legal scheme Roe devised for surgical abortion. RU-486 may eventually be developed as a contraceptive because it can be used monthly whether or not a woman is pregnant and it would fit within federal regulations governing contraception. A distinction is made between contraception and abortion and if RU-486 is used as a contraceptive its classification could be affected. If the FDA classified the new pill as a contraceptive its use in the US could be legally insulated from Supreme Court action on abortion.
Dkk-1-mediated expansion of adult stem cells

Despite the wealth of research on stem-cell biology and therapy, there have been few advances in the ex vivo expansion of adult stem cells. Fetal bovine serum, which can elicit an immune reaction in hosts receiving cellular products, remains essential to the culture methods. Recent work by Prockop et al. suggests that Dickkopf-1 (Dkk-1) could stimulate the proliferation of mesenchymal stem cells (MSCs) while maintaining an undifferentiated phenotype. The use of Dkk-1 in cell-processing laboratories might advance cell-expansion technology and greatly increase the clinical uses of MSCs.
Can competitive paradigms increase the validity of experiments on primate social cognition

Experiments vary in their ability to distinguish between competing hypotheses. In tests on primate cognition the majority of this variation is due to an experimenter’s ability to test primates in valid settings while providing the adequate amount of experimental control. While experimenters studying primate cognition can use methods of control perfected in captivity, it is still very unclear how to design and then objectively evaluate the external validity of new experimental paradigms. I recommend that more effort be allocated to specify how to create relevant test settings for primates. Primate social life is highly competitive. This means that all aspects of primates themselves, including their cognitive abilities, have likely been shaped by the need to out-compete conspecifics. Based on this hypothesis, sophisticated cognitive abilities of primates might best be demonstrated in competitive contexts. Thus, it is suggested that one possible measure of validity is whether investigators integrate a competitive component into their experimental designs. To evaluate this methodological prediction I review the literature on chimpanzee perspective-taking as a case study including several recent studies that include a competitive component in their experimental designs.
E-027 Evolution of dolichoectatic dilatations to large and giant aneurysms in the anterior and posterior circulations

Introduction Dolichoectatic dilatation in intracranial arteries may enlarge, however the evolution of this progression has not been described. We present 3 cases with intracranial vascular imaging spanning for a period of 10 years demonstrating growth of dolichoectatic dilatations to large and giant aneurysms, which were eventually treated by various modalities. Cases Case 1: 49 year old man who had brain imaging in 2002 demonstrating dolichoectatic dilatation of the right internal carotid, anterior cerebral and middle cerebral arteries with maximal diameter of 6mm, presented in 2011 with seizures related to mass effect in the right mesial temporal lobe. Cerebral angiogram demonstrated growth of the aneurysm to a maximal diameter of 29mm, involving the right internal carotid, anterior and middle cerebral artery (figure demonstrating MRI from 2002 and angiogram from 2011). The patient was treated successfully with high flow bypass and right ICA endovascular sacrifice. Case 2: 63 year old woman who had brain MRI in 2000 demonstrating no aneurysms, presented in 2011 with headache and subacute subarachnoid haemorrhage. The angiogram demonstrated dysplastic left MCA with fusiform dilatation and 3 irregular aneurysms. She was successfully treated with SCA/MCA bypass. Case 3: 37 year old man with an MRI from 2000 demonstrating dolichoectatic basilar artery with maximal diameter of 6mm, presented in 2013 with brainstem compression and the angiogram showed growth into a dysplastic giant basilar aneurysm with maximal diameter of 30mm. The patient was treated surgically. Discussion These cases describe symptomatic and imaging progression of dolichoectatic vessels to large and giant aneurysms in the anterior and posterior circulation for extended period of time. Interval and duration of follow up in this patient population has not been well described, however, progression may occur for long period of time, as demonstrated in our cases with imaging for over ten years. Frequent and long term imaging evaluation may be recommended in the follow up of these patients. Disclosures E. Cheng-Ching: None. G. Toth: None. R. Burgess: None. M. Hussain: None. M. Bain: None.
FLOWMETER ANALYSIS AT RAFT RIVER, IDAHO

A quantitative evaluation of borehole-impeller flowmeter data leads to estimated field hydraulic conductivity. Data were obtained during an injection test of a geothermal well at the Raft River geothermal test site in Idaho. Both stationary and trolling calibrations of the flowmeter were made in the well. Methods were developed to adjust for variations in hole diameter, impeller speed, and trolling speed. These methods were applied to evaluate water losses into the formation as a function of depth. Application of the techniques is restricted to aquifers below the water table. The flowmeter data were digitized and processed by the computer to obtain plots of apparent field hydraulic conductivity versus depth.
Difficulty Disengaging Attention from Social Threat in Social Anxiety

Selective attention to threat is believed to maintain social anxiety, yet the nature of attentional processing remains unclear. It has been posited that difficulty disengaging from threat cues may be implicated. The present study tested this hypothesis using an eye tracking paradigm to directly examine eye fixations in a non-clinical sample (N = 46). Eye movements were tracked during presentation of social cues (happy or disgust faces) embedded with non-social cues matched on dimensions of valence, threat, and arousal. Stimuli were presented for 2,000 ms to allow for examination of attention over time. Results suggest that individuals with higher social anxiety may demonstrate relative difficulty disengaging from negative social cues (i.e., disgust faces). Social anxiety was unrelated to eye movements concerning happy faces. Implications for the maintenance and etiology of social anxiety are discussed.
A model describing the steady-state gasification of bubble-forming thermoplastics in response to an incident heat flux

A theoretical model is developed to describe the in-depth effect of bubbles on the steady-state transport of volatile gases from the surface of a thermoplastic material subjected to an incident conductive heat flux. In this model the effect of the bubbles on the surrounding liquid is felt through the bubble number distribution function, n, which appears in the equations for conservation of mass, momentum, species, and energy in the melt. The equation describing the evolution of n includes the effects of bubble growth, convection, and nucleation. Formulas for the mass flux of volatiles and the bubble void fraction for gasifying PMMA are developed from the conservation equations, for the special case of a constant polymer mass fraction in the liquid phase.
Confirmation of Faraday's explanation of bunkering in vibrated granular beds

Abstract Faraday, like Chladni earlier, saw a shallow layer of a fine powder collect in a circular heap (a ‘minibunker’) at an antinode of a vibrating plate. He saw ‘Faraday circulation’: powder motion in a shallow surface layer of the heap, downward from its center to its edge; inward motion centerward at the edge; by inference, motion upward toward the middle of the heap's interior. What he saw led him to postulate formation of a partial vacuum beneath the powder heap, creating (1) an external wind blowing the powder toward an antinode and (2) a flow of air inward from the heap's edge, driving powder toward its center. Although some experimentalists have recently advanced alternative explanations of vibrated-bed heaping (‘bunkering’), we are able to confirm the essentials of Faraday's thought. At suitable amplitude and frequency, vertical sinusoidal vibration of a fine-powder bed causes it, in each vibration cycle, to experience a free-flight interval during which pressure gradients in its interior drive powder centerward. A center-high bunker forms, displaying Faraday circulation. When bed-floor collision terminates flight, pressure gradients reverse direction; but passage of a compaction front has locked particles against further movement. Before a next flight interval, an increase in porosity will reverse the compaction that accompanied heap-floor collision. In particles 177-μm and larger, we see the compaction front cinematographically; in 88-μm particles, we infer it from floor-pressure data. Although, given sufficient time, a bed of large particles (e.g., 707 μm) will form a bunker, it displays the wall-friction-driven circulation elucidated by Muchowski, not the Faraday pattern.
Recognition masking of auditory duration

Forward and backward recognition masking of tonal duration were assessed using young adults as listeners. The task was to label as “short” or “long” a target tone that had a masking tone following or preceding it by a variable silent interstimulus interval (ISI). Forward- and backwardmasking effects were virtually equivalent. On both forward- and backward-masking trials, (1) percentages correct increased with increases in ISIs, (2) the probability of responding “long” to the target increased with increases in ISIs, and (3) the probability of responding “long” increased with increases in the duration of the mask. The equivalence of backward and forward duration masking argues against an interruption theory of duration masking. It is suggested that some form of integration theory, preferably one that includes components unique to the perception of duration, may better account for the results.
The acceleration of linear DNA during pulsed‐field gel electrophoresis

The velocity and orientation of T4 and lambda DNA have been measured for the first 20 s during pulsed-field gel electrophoresis in order to clarify the DNA motions that occur. For a square pulse with field strength E = 10 V/cm, the velocity of lambda DNA increases gradually to 10.5 microns/s in 1.0 s, declines to 8.6 microns/s, and then rises to a plateau value of 9.3 microns/s after 4 s. T4 DNA behaves similarly, but more slowly. Parallel measurements of fluorescence-detected linear dichroism show that the DNA becomes substantially aligned with its chain axis parallel to the electrophoretic field E after the pulse is applied. The alignment also shows an overshoot, an undershoot, and a plateau comparable to those seen for velocity. When the field strength increases, both the velocity and the alignment reach their peaks more quickly. For all field strengths and both molecular weights, the velocity peak occurs when the molecular center of mass has moved 0.3 to 0.5 L, where L is the chain contour length. A qualitative model is provided.
The influence of structure and conformation on electronic interactions of 4′-nitro-10-phenylphenothiazine

The crystal structure of 4′-nitro-10-phenylphenothiazine, 1, has been determined by the single crystal x-ray diffraction studies and consists of two independent molecules in the asymmetric cell unit with a pseudo-center of symmetry. The crystal belongs to the monoclinic System with the space group P21/c. The central ring of the phenothiazine ring system is in a boat conformation and the 4′-nitro substituent is in a boat-axial conformation with respect to the central ring of phenothiazine. Compound 1 is the first reported 10-aryl phenothiazine in which the 10-phenyl ring is perpendicular to the plane bisecting the dihedral angle of the phenothiazine nucleus. This geometry allows for resonance interaction between the lone pair of electrons on N10 and the 4′-nitro-10-phenyl ring which influences both the spectral properties and structure of the phenothiazine tricyclic ring. The correlation between the x-ray structure and 13C nmr spectral properties of 1 is discussed. The uv/vis and esr studies of the radical cation of 1 indicate that the 10-aryl ring is twisted with respect to the phenothiazine ring.
Anesthetic management of preschool children with penetrating eye injuries: postal survey of pediatric anesthetists and review of the available evidence.

Summary Background : Pediatric anesthetists were surveyed regarding their anesthesia management of a screaming child with a penetrating eye injury. The results are reviewed in relation to the available evidence in the literature. Methods : A postal survey was sent to all the members of the APA living in the UK. Seven clinical questions were asked regarding the management of penetrating eye injury and two questions regarding seniority and the number of cases seen. Results : Of the 318 questionnaires sent out 238 were evaluated. Of the responders indicating the number of cases seen, 21.2% had never seen a single case, 55.1% had seen 10 cases. Suxamethonium was used more often by respondents who had handled more cases; 42.9% of those doing >10 compared with 10% of those doing less than five cases. Senior anesthetists preferred the use of techniques without relaxants and to extubate children under deep anesthesia. Conclusions : Few people have extensive experience managing a penetrating eye injury in a child. A variety of anesthesia techniques are used for induction with anesthetists avoiding suxamethonium, despite there being little evidence in the literature that the use of suxamethonium is harmful to the open globe.
Solvent dependence of peptide carbonyl carbon chemical shifts and polypeptide secondary structure: the repeat tetrapeptide of elastin.

Summary It is demonstrated that carbon-13 magnetic resonance may be used to evaluate polypeptide secondary structure by noting the solvent dependence of peptide carbonyl carbon chemical shifts. Solvent pairs are utilized in which one solvent is a poor proton (or deuteron) donor and the second is a good proton (or deuteron) donor. The peptide carbonyl carbon resonance of the carbonyl shielded from the solvent by intramolecular hydrogen bonding exhibits less downfield shift on introduction of CD3OD, D2O or 2,2,2-trifluoroethanol-d3 to dimethylsulfoxide-d6 solutions than do those of peptide carbonyls that are more exposed to the solvent. The approach is illustrated with the elastin repeat tetrapeptide, Val1-Pro2-Gly3-Gly4, wherein the Val1 C -O is solvent shielded due to intramolecular hydrogen bonding to the Gly4 N H .
Interaction between prostaglandins and cyclic amp in the gastric mucosa

Possible mechanisms accounting for the inhibition of acid secretion by prostaglandins were studied using cells dispersed from canine fundic mucosa by enzymes and enriched in the content of parietal cells by elutriation. The accumulation of 14C-aminopyrine (AP) was used as an index of parietal cell response to stimulation. PGE2 inhibited histamine-stimulated AP uptake, with 50% inhibition (ID50) found at 10 nM, but did not block the response to carbachol, gastrin, or dibuturyl cyclic AMP. PGE2 did, however, inhibit aminopyrine uptake stimulated by carbachol and gastrin when the response to these agents was potentiated by histamine. PGE2, at namomolar concentrations, also inhibited histamine-stimulated cyclic AMP production. When mucosal cells were treated with only PGE2 at concentrations above 1 μM, stimulation of cyclic AMP production was found. In cell separation studies with the elutriator rotor, PGE2 appeared to stimulate cyclic AMP production primarily in nonparietal cells. Prostacyclin (PGI2) and two stable analogues, 6β-PGI1 and the 16-phenoxy analogue (5α)5,9-epoxy-16-phenoxy-PGF1, also specifically inhibited histamine-stimulated AP accumulation. PGI2 required relatively high concentrations for this effect (ID50 = 1 μM), whereas the 16 phenoxy derivative was much more potent in its inhibition of histamine-stimualted AP accumulation (ID50 = 10 nM), with this difference probably accounted for by the rapid degradation of PGI2 compared to the stable 16-phenoxy analogue. All three of these prostanoids also inhibited histamine-stimulated cyclic AMP production. As was found with PGE2, at high concentrations and in the absence of histamine PGI2 and PGI1 also stimulated cyclic AMP production. However, the 16-phenoxy analogue failed to stimulate cyclic AMP production either in the parietal cell enriched fractions or in the nonparietal cell fractions. These data indicate that PGE2 and prostacyclin analogues are potent, direct and specific inhibitors of histamine-stimulated parietal cell function and that it is the inhibition, rather than the stimulation, of cyclic AMP formation that is linked to the antisecretory actions of the prostanoid compounds.
Redox transformations of arsenic and iron in water treatment sludge during aging and TCLP extraction.

Laboratory experiments and modeling studies were performed to investigate the redox transformations of arsenic and iron in water treatment sludge during aging, and to evaluate the impact of those transformations on the leachability of arsenic determined with the U.S. EPA toxicity characteristic leaching procedure (TCLP). When the backwash suspension samples collected from a California surface water treatment plant were aged in closed containers for a few weeks, soluble arsenic increased from less than 5 microg/L to as high as 700 microg/L and then decreased dramatically because of biotic reduction of arsenate [As(V)], ferric oxyhydroxide, and sulfate. The experimental results and the thermodynamic models showed that arsenic mobility can be divided into three redox zones: (a) an adsorption zone at pe > 0, which is characterized by strong adsorption of As(V) on ferric oxyhydroxide; (b) a mobilization (transition) zone at -4.0 < pe < 0, where arsenic is released because of reduction of ferric oxyhydroxide to ferrous iron and As(V) to arsenite [As(III)]; and (c) a reductive fixation zone at pe < -4.0, where arsenic is immobilized by pyrite and other reduced solid phases. The TCLP substantially underestimated the leachability of arsenic in the anoxic sludge collected from sludge ponds because of the oxidation of Fe(II) and As(III) by oxygen. The leaching test should be performed in zero-headspace vessels or under nitrogen to minimize the transformations of the redox-sensitive chemical species.
Computing as a general education requirement

It has been about fifty years since the computer age began, and it is clear that the computer has had and will continue to have a strong, multifaceted, influence on every person in this nation. The computer is effecting a profound change in society; some say the scope of this change rivals that of Gutenberg's movable type. Yet many college students are not currently required to study the computer, computing, and their societal impact. This paper discusses the need for computer course in the general-education requirements for a baccalaureate degree. It also addresses the issues of where in that curriculum such a course might be listed (humanities, mathematics/natural science, or social science) and who should be entrusted to teach it.
Further studies on the biological properties of friend virus-induced leukemic cells differentiating along the erythrocytic pathway.

When Friend virus-induced leukemic cell lines were injected into irradiated hosts after the second radiation dose, the colony-forming unit (CFU) in the recipient spleens per 104 cells was found to be 7-fold higher than the CFU obtained when the second radiation dose had been given shortly after the inoculation of the cells. Serial passage of the cells from the spleen colonies to irradiated hosts resulted in a marked increase of the CFU value, indicating that this cell population was capable of both self-replication and erythroid differentiation. The “f” fraction, which indicates the percentage of the inoculated cells that reach the spleen in the irradiated recipients, was found to be approximately 15%. If the highest CFU value obtained from serial colony-to-colony passages is corrected by this factor, a final cloning efficiency of about 18% is demonstrated. Neither induced plethora nor the administration of erythropoietin (1 u/mouse/for 2 days) appeared to affect the spleen colony-forming ability of the leukemic cells. Erythroid differentiation is not detectable in the transplantable subcutaneous tumors which were used to initiate the tissue culture lines and which also are capable of inducing erythroid spleen clones in irradiated recipients. This lends support to the theory of the influence of “microenvironmental factors” on the fate of stem cells with potential for differentiation.
A biologically active thrombin cleavage product of human serum spreading factor

Purified human serum spreading factor preparations consisting of two immunologically-related, biologically-active proteins of molecular weights approximately 65,000 and 75,000 were incubated with purified hydrolytic enzymes: papain, neuraminidase and thrombin. Biologically active products of the enzymatic digestions were obtained in each case. Digestion of serum spreading factor preparations with thrombin produced a single active form of molecular weight approximately 57,000. Generation of a single molecular weight form of serum spreading factor by thrombin cleavage of the two higher molecular weight forms should simplify studies of the biochemistry and biology of this protein, and may represent a reaction of physiological significance.
Molecular characterization of Nipah virus, a newly emergent paramyxovirus.

Recently, a new paramyxovirus, now known as Nipah virus (NV), emerged in Malaysia and Singapore, causing fatal encephalitis in humans and a respiratory syndrome in pigs. Initial studies had indicated that NV is antigenically and genetically related to Hendra virus (HV). We generated the sequences of the N, P/C/V, M, F, and G genes of NV and compared these sequences with those of HV and other members of the family Paramyxoviridae. The intergenic regions of NV were identical to those of HV, and the gene start and stop sequences of NV were nearly identical to those of HV. The open reading frames (ORFs) for the V and C proteins within the P gene were found in NV, but the ORF encoding a potential short basic protein found in the P gene of HV was not conserved in NV. The N, P, C, V, M, F, and G ORFs in NV have nucleotide homologies ranging from 88% to 70% and predicted amino acid homologies ranging from 92% to 67% in comparison with HV. The predicted fusion cleavage sequence of the F protein of NV had a single amino acid substitution (K to R) in comparison with HV. Phylogenetic analysis demonstrated that although HV and NV are closely related, they are clearly distinct from any of the established genera within the Paramyxoviridae and should be considered a new genus.
Kinetics of the CCO + NO and CCO + NO2 Reactions

The kinetics of the reaction of CCO radicals with NO and NO2 were studied using time-resolved infrared diode laser absorption spectroscopy. The rate constants were determined to be kCCO+NO = (5.36 ...
Exoenzyme kinetics with applications to the determination of nucleotide sequences

The kinetics of the action of exoenzymes on linear polymers is developed. The results are applied to the problem of sequence determination in nucleic acids. It is found that a choice of experimental conditions different from the steady-state situation provides a liberation of successive nucleotides in better resolved time intervals. The inference of the nucleotide sequence of a hypothetical dodecamer is explored in detail. Calculations indicate the possibility of determining the base sequences of oligomers containing up to 25 nucleotides.
A new theory of laughter

L'A. examine trois theories du rire (provenant d'un sentiment de superiorite, d'une sensation d'incongruite ou de soulagement) avant d'exposer la sienne propre. Il examine brievement les theories de Hobbes, Aristote, Spencer, Freud, du point de vue de cette classification. Il critique notamment la distinction freudienne entre mot d'esprit et comique. L'A. definit le rire en dissociant rire et humour: selon lui, le rire provient de tout changement psychologique agreable.
Continuous labor support from labor attendant for primiparous women: a meta-analysis.

Objective To evaluate the available literature on the effects of continuous labor support among primiparous women. Data Sources We did a Medline search using the key words “labor support,” “doula,” and “monitrice.” Papers published in English from 1965 to May 1995 were eligible for this review. We also cross-checked all the references in the selected reports. Methods of Study Selection We identified seven randomized clinical trials published during that period; four of these were eligible for our meta-analysis. Data Extraction and Synthesis Meta-analysis of four studies conducted among young, low-income, primiparous women who gave birth on a busy labor floor in the absence of a companion suggested that continuous labor support by a labor attendant shortens the duration of labor by 2.8 hours (95% confidence interval [CI] 2.2-3.4), doubles spontaneous vaginal birth (relative risk [RR] 2.01, 95% CI 1.5–2.7) and halves the frequency of oxytocin use (RR 0.44, 95% CI 0.4–0.7), forceps use (RR 0.46, 95% CI 0.3–0.7), and cesarean delivery rate (RR 0.54, 95% CI 0.4–0.7). Women with labor support also reported higher satisfaction and a better postpartum course. Conclusion Labor support may have important positive effects on obstetric outcomes among young, disadvantaged women. Further studies on benefit relative to cost are needed before a broad-scale program is advocated.
Genes and Sjögren's Syndrome

The evidence for a strong genetic component conferring susceptibility to primary Sjogren's syndrome (SS) is mounting. Several associations with SS have been reported and provide evidence that the HLA region harbors important susceptibility loci and that multiple genes outside the HLA region play a role. Genetic discovery lags behind success observed in related autoimmune diseases. Identifying genetic factors that cause SS will allow more precise definition of pathogenic mechanisms leading to the overall SS phenotype and clinically heterogeneous subsets of patients. Critical opportunities are certain to follow for translation into improved diagnosis and therapies for SS and its spectrum diseases.
Urinary Cortisol in the Assessment of Pituitary-Adrenal Function: Utility of 24-Hour and Spot Determinations

To more conveniently assess dynamic changes in the biologically active fraction of cortisol, we measured cortisol in 1-h urine samples obtained from 0700-0800 and from 2200-2300 h. In 20 normal subjects, morning 1-h urinary cortisol levels were 78 +/- 36 ng/mg creatinine (mean +/- SD), whereas levels from 2200-2300 h were 22 +/- 12 ng/mg creatinine, demonstrating diurnal variability. In 14 patients with Cushing's syndrome, mean morning urinary cortisol was elevated (207 +/- 176 ng/mg creatinine), but there was overlap with values in normal subjects. In contrast, evening values in Cushing's syndrome (248 +/- 208 ng/mg creatinine) were elevated in each patient; there was no diurnal variation and no overlap with normal subjects. Similarly, the morning urinary cortisol response to dexamethasone (1 mg, orally, at 2300 h) clearly separated normal subjects from those with Cushing's syndrome (5 +/- 6 vs. 169 +/- 149 ng/mg creatinine, respectively). In 10 patients with secondary hypoadrenalism, urinary cortisol levels were less than 2 ng/mg creatinine in both morning and evening 1-h samples. Thus, the determination of cortisol in 1-h samples is a practical and simple method of assessing cortisol secretion and allows multiple sampling without hospitalization. It is effective in assessing dynamic cortisol responses, such as diurnal variation and responsiveness to suppression, and it is an effective screening test for Cushing's syndrome and hypoadrenalism.
Psychosocial issues during the acute treatment of pediatric cancer.

Facilitating the psychosocial adjustment of the child with cancer begins at the time of diagnosis. This paper reviews the current status of psychosocial research and interventions useful during the acute phase of cancer treatment. Factors related to a favorable adaptation include the child's understanding of what is happening and the ability of the family to provide emotional support. Recent data suggest that a child's adjustment is closely linked to the social supports available to the parents and to parental distress levels. Continued progress has been made in the use of psychological techniques to control the behavioral side effects of chemotherapy and children's distress levels during painful medical procedures. New research has also identified a number of factors related to treatment refusal and noncompliance among adolescent cancer patients. These new developments provide a basis for programs aimed at preventing or reducing the psychosocial problems of the child and family facing pediatric cancer. Cancer 58:468-472, 1986.
Measuring reversible adsorption kinetics of small molecules at solid/liquid interfaces by total internal reflection fluorescence correlation spectroscopy

Reversible adsorption kinetics of a cationic dye molecule at a C-18 modified silica surface are measured in a fluorescence correlation spectroscopy experiment. An interfacial observation volume is defined by total internal reflection of a laser beam which excites fluorescence emission from Rhodamine 6G (R6G+) in adsorption equilibrium with the surface. Spontaneous fluctuations in the population of R6G+ molecules within the interfacial volume are observed as excess low-frequency noise superimposed on a fluorescence transient. Autocorrelation of the transient allows the temporal characteristics of the fluctuations to be examined. The rate at which fluctuations occur depends on transport of molecules to the interface and their adsorption kinetics. Adsorption and desorption rates of R6G+ in water/methanol solutions at a C-18 modified silica/solution interface were measured over a 3 order of magnitude range of the retention equilibrium; both rates were found to depend strongly on the composition of the overlyi...
Transmission of topological surface states through surface barriers

Topological states have become the subject of much attention from condensed-matter physicists, as evidence accumulates to show that these states can be found on the surface of certain materials — in particular, bulk compounds called topological insulators. As a product of their topological nature, topological surface states are predicted to have the remarkable property of being robust against imperfections. This can allow, for example, the conduction of electronic currents without dissipation. Ali Yazdani and his team now report a tantalizing finding from scanning tunnelling microscope measurements — that topological surface states on antimony can be transmitted with high probability through naturally occurring barriers that stop other conventional surface states of common metals. The authors suggest that their findings indicate that topological surface states could be exploited in novel applications of nanoscale electronic devices. Topological surface states are a class of electronic states that might be of interest in quantum computing or spintronic applications. They are predicted to be robust against imperfections, but so far there has been no evidence that these states do transmit through naturally occurring surface defects. Here, scanning tunnelling microscopy has been used to show that topological surface states of antimony can be transmitted through naturally occurring barriers that block non-topological surface states of common metals. Topological surface states are a class of novel electronic states that are of potential interest in quantum computing or spintronic applications1,2,3,4,5,6,7. Unlike conventional two-dimensional electron states, these surface states are expected to be immune to localization and to overcome barriers caused by material imperfection8,9,10,11,12,13,14. Previous experiments have demonstrated that topological surface states do not backscatter between equal and opposite momentum states, owing to their chiral spin texture15,16,17,18. However, so far there is no evidence that these states in fact transmit through naturally occurring surface defects. Here we use a scanning tunnelling microscope to measure the transmission and reflection probabilities of topological surface states of antimony through naturally occurring crystalline steps separating atomic terraces. In contrast to non-topological surface states of common metals (copper, silver and gold)19,20,21,22,23, which are either reflected or absorbed by atomic steps, we show that topological surface states of antimony penetrate such barriers with high probability. This demonstration of the extended nature of antimony’s topological surface states suggests that such states may be useful for high current transmission even in the presence of atomic-scale irregularities—an electronic feature sought to efficiently interconnect nanoscale devices.
Zeff behavior following Li and C pellet injection into TFTR

Injection of both Li and C pellets into TFTR discharges has provided a variety of almost instantaneous changes to the normal equilibrium profiles. The profile measurements of visible bremsstrahlung intensity, electron density, and temperature were used to deduce Zeff profiles versus time. The evolution Zeff is examined in L mode and supershot cases. A comparison is made to the soft x‐ray profile behavior for these same conditions.
Emissivity and the Fate of Pluto's Atmosphere

Abstract We present a simplified model for seasonal changes in Pluto's surface–atmosphere system. The model demonstrates the potential importance of the solid-state phase transition between α-N 2 and β-N 2 , and the accompanying change in emissivity, for predicting the seasonal bulk of Pluto's (and Triton's) atmosphere. Specifically, the model shows that under simplified but not unreasonable assumptions Pluto may have nearly the same atmospheric pressure at aphelion as it does now, near perihelion. The emissivity change which accompanies the α–β phase change should be included in the next generation of Pluto and Triton seasonal models for the purposes of understanding the evolution of their atmospheres over seasonal and climatic timescales.
Responses of Lyngbya wollei to Exposures of Copper-Based Algaecides: The Critical Burden Concept

The formulation of a specific algaecide can greatly influence the bioavailability, uptake, and consequent control of the targeted alga. In this research, three copper-based algaecide formulations were evaluated in terms of copper sorption to a specific problematic alga and amount of copper required to achieve control. The objectives of this study were (1) to compare the masses of copper required to achieve control of Lyngbya wollei using the algaecide formulations Algimycin-PWF, Clearigate, and copper sulfate pentahydrate in laboratory toxicity experiments; (2) to relate the responses of L. wollei to the masses of copper adsorbed and absorbed (i.e., dose) as well as the concentrations of copper in the exposure water; and (3) to discern the relation between the mass of copper required to achieve control of a certain mass of L. wollei among different algaecide formulations. The critical burden of copper (i.e., threshold algaecide concentration that must be absorbed or adsorbed to achieve control) for L. wollei averaged 3.3 and 1.9 mg Cu/g algae for Algimycin-PWF and Clearigate, respectively, in experiments with a series of aqueous copper concentrations, water volumes, and masses of algae. With reasonable exposures in these experiments, control was not achieved with single applications of copper sulfate despite copper sorption >13 mg Cu/g algae in one experiment. Factors governing the critical burden of copper required for control of problematic cyanobacteria include algaecide formulation and concentration, volume of water, and mass of algae. By measuring the critical burden of copper from an algaecide formulation necessary to achieve control of the targeted algae, selection of an effective product and treatment rate can be calculated at a given field site.
Use of T4 lysozyme charge mutants to examine electrophoretic models.

The electrophoretic mobility of a macro-ion is affected in a complex manner by a variety of forces that arise from the applied field. Coupling of the macro-ion and small-ion flows gives rise to non-conserved forces that are greater than those expected from ordinary hydrodynamic considerations. It is difficult to separate the steady-state hydrodynamic and electrodynamic contributions to the macro-ion mobility. Membrane-confined electrophoresis (MCE), a free solution technique, provides an experimental means by which to gain insight into these contributions. In this work we used MCE steady-state electrophoresis (SSE) of a series of T4 lysozyme charge mutants to investigate these effects and to examine the existing theoretical descriptions. These experiments isolate the effects of charge on electrophoretic mobility and permit a unique test of theories by Debye-Huckel-Henry, Booth and Allison. Our results show that for wild type (WT) T4, where divergence is expected to be greatest, the predicted results are within 15, 8 and 1%, respectively, of experimental SSE results. Parallel experiments using another free-solution technique, capillary electrophoresis, were in good agreement with MCE results. The theoretical predictions were within 20, 13 and 5% of CE mobilities for WT. Boundary element modeling by Allison and co-workers, using continuum hydrodynamics based on detailed structural information, provides predictions in excellent agreement with experimental results at ionic strengths of 0.11 M.
A new non-linear optimal control method: the tracking and relative direction imbedded system

Abstract A new method of determining the optimal control for non-linear systems is described. It employs a novel course correction mechanism to optimize the state with respect to the initial condition and then uses dynamic programming to optimize the control with respect to the final condition. A non-linear closed-form relationship of the cost function was developed so that the multi-grid approach of dynamic programming is avoided. Unlike other solution methods for optimal control problems, it does not need an estimate of the nominal solution to start the algorithm. One backward pass generates the optimal state trajectory, which is then tracked during the execution of the manoeuver. Compared to the multipasses necessary for other methods, this new method provides a significant improvement in computation time.
Outcome Studies in the Treatment of Panic Disorder: A Review

The authors review outcome studies in the treatment of panic disorder without agoraphobia for an adult population. Empirical evidence is presented to support the efficacy of psychopharmacological and cognitive-behavioral interventions. In addition, this article can serve as the basis for the development of emerging standards of cure for the diagnosis and treatment of panic disorder.
Space-Current Division in the Power Tetrode

In the conventional power tetrode, when operating within the normal range of electrode voltages, changes in plate potential do not appreciably affect the total space current or its division at the grid plane. Furthermore, changes in grid potential, although affecting to a large degree the magnitude of the space current reaching the screen plane, do not alter materially the division of this current between screen and plate. Making use of these facts, and taking into account the effect of initial velocities of emission and contact potential, each electrode current can be expressed in terms of the 3/2 power of an equivalent voltage and an empirical function. These empirical functions can be plotted on a log-log chart in a manner that allows the complete static curve data to be easily determined for any grid, screen, and plate voltage within the normal operating range. Methods of determining experimentally the empirical functions at low power levels are described. A sample log-log chart and an explanation of its use are presented.
Solutions of the KP equation associated to rank-three commuting differential operators over a singular elliptic curve

Abstract We give a method for finding explicit solutions of the Kadomtsev-Petviashvili (KP) equation which are associated to rank-three commuting ordinary differential operators. Explicit formulae for the coefficients of rank-three commuting differential operators are used to reduce the KP equation to a nonlinear partial differential equation in only two variables. This equation, which is obtained in a similar way to the rank-two Krichever-Novikov (KN) equation, is easier to solve than KP and some solutions are given.