cssi/SciSciGPT-SciSciNet huggingface dataset:
Factors affecting the extractability and MAK chromatography of nucleic acids from woody plant tissue

Abstract Factors affecting the yield of the different classes of nucleic acids extracted from woody plant tissues were investigated using MAK chromatography. Sodium lauryl sulfate (2·0%) improved the yields of nucleic acids by 187 per cent. Shaking of the homogenate for 30 min increased yields an additional 40 per cent, probably by allowing sodium lauryl sulfate to more effectively dissociate nucleic acids from protein and membranes. In Korean boxwood leaves, the addition of phenol before the liberation of nucleic acids by sodium lauryl sulfate reduced yields of DNA and r-RNA. Lyophilization of tissues permitted the use of dry grindign techniques which improved cell breakage and increased yields of nucleic acids. Nucleic acid degradation during lyophilization, due to the thick tissue cuticle which prevented evaporative cooling, was minimized by maintaining the sample at −20° during drying. Precipitation of nucleic acids from dogwood bark with 2-ethoxyethanol at 0–4° improved MAK separation by eliminating interfering substances which competed with nucleic acids for binding sites on the MAK column. Degradation of precipitated nucleic acids by sodium lauryl sulfate was prevented by removing it with ether prior to precipitation.
Studies of insulin secretion in infantile hypoglycemia

Studies were carried out to evaluate insulin secretion and its suppressability by epinephrine in 6 infants with severe fasting hypoglycemia prolonged into the first year of life. All infants required constant glucose infusions to maintain blood glucose above 40mg%. Decreased hepatic glucose output was responsible for the hypoglycemia in two of the infants (one with isolated ACTH deficiency and one with fructose-1,6-diphosphatase deficiency), whereas increased peripheral utilization of glucose was causative in the remaining four infants (two with islet cell hyperplasia and two with insulinoma). In all cases the rate of glucose infusion was adjusted to produce a peripheral blood glucose of 80 to 100 mg%. The infants with reduced hepatic glucose output had significantly slower rates of glucose infusion and significantly lower plasma insulin concentrations. The infants were next infused with the same amounts of glucose containing epinephrine and propanolol for one hour. Epinephrine completely suppressed plasma insulin (to levels of <12uU/ml) in the infants with decreased hepatic glucose output and beta cell hyperplasia, but had little or no effect on insulin concentrations in the two infants with insulinoma. In all cases the efficacy of propanolol blockade was attested to by the absence of any change in plasma free fatty acid concentrations. Islet cell hyperplasia may be distinguished from insulinoma preoperatively in this way.
Remarks on Radio in Brazil

The history of radio in Brazil is nearly as old as that in the United States. While some sources trace the history of radio in the United States through the Marconi stations as early as 1901 (McNic...
Effects of Handling or Immobilization on Plasma Levels of 3,4‐Dihydroxyphenylalanine, Catecholamines, and Metabolites in Rats

Abstract: In conscious animals, handling and immobilization increase plasma levels of the catecholamines norepinephrine (NE) and epinephrine (EPI). This study examined plasma concentrations of endogenous compounds related to catecholamine synthesis and metabolism during and after exposure to these stressors in conscious rats. Plasma levels of 3,4-dihydroxyphenylalanine (DOPA). NE, EPI, and dopamine (DA), the deaminated catechol metabolites 3,4-dihydroxyphenylglycol (DHPG) and 3,4-dihydroxyphenylacetic acid (DOPAC), and their O-methylated derivatives methoxyhydroxyphenylglycol (MHPG) and homovanillic acid (HVA) were measured using liquid chromatography with electrochemical detection at 1,3, 5, 20, 60, and 120 min of immobilization. By 1 min of immobilization, plasma NE and EPI levels had already reached peak values, and plasma levels of DOPA, DHPG, DOPAC, and MHPG were increased significantly from baseline, whereas plasma DA and HVA levels were unchanged. During the remainder of the immobilization period, the increased levels of DOPA, NE, and EPI were maintained, whereas levels of the metabolites progressively increased. In animals immobilized briefly (5 min), elevated concentrations of the metabolites persisted after release from the restraint, whereas DOPA and catecholamine levels returned to baseline. Gentle handling for 1 min also significantly increased plasma levels of DOPA, NE. EPI, and the NE metabolites DHPG and MHPG, without increasing levels of DA or HVA. The results show that in conscious rats, immobilization or even gentle handling rapidly increases plasma levels of catecholamines, the catecholamine precursor DOPA, and metabolites of NE and DA, indicating rapid increases in the synthesis, release, reuptake, and metabolism of catecholamines.
Advanced Technical Skills Are Required for Microsurgical Clipping of Posterior Communicating Artery Aneurysms in the Endovascular Era

BACKGROUND Many neurosurgeons feel competent clipping posterior communicating artery (PCoA) aneurysms and include this lesion in their practice. However, endovascular therapy removes simple aneurysms that would have been easiest to clip with the best results. What remains are aneurysms with complex anatomy and technical challenges that are not well described. OBJECTIVE A contemporary surgical series with PCoA aneurysms is reviewed to define the patients, microsurgical techniques, and outcomes in current practice. METHODS A total of 218 patients had 218 PCoA aneurysms that were treated microsurgically during an 11-year period. Complexities influencing aneurysm management included (1) large/giant size; (2) fetal posterior cerebral artery; (3) previous coiling; (4) anterior clinoidectomy; (5) adherence of the anterior choroidal artery (AChA); (6) intraoperative aneurysm rupture; (7) complex clipping; and (8) atherosclerotic calcification. RESULTS Simple PCoA aneurysms were encountered in 113 patients (51.8%) and complex aneurysms in 105 (48.2%). Adherent AChA (13.8%) and intraoperative rupture (11.5%) were the most common complexities. Simple aneurysms had favorable outcomes in 86.6% of patients, whereas aneurysms with 1 or multiple complexities had favorable outcomes in 78.2% and 75.0%, respectively. Intraoperative rupture (P < .01), large/giant size (P = .04), and complex clipping (P = .05) were associated with increased neurological worsening. CONCLUSION Because endovascular therapy alters the surgical population, neurosurgeons should recalibrate their expectations with this once straightforward aneurysm. The current mix of PCoA aneurysms requires advanced techniques including clinoidectomy, AChA microdissection, complex clipping, and facility with intraoperative rupture. Microsurgery is recommended for recurrent aneurysms after coiling, complex branches, aneurysms causing oculomotor nerve palsy, multiple aneurysms, and patients with hematomas.
The health and economic benefits of influenza vaccination for healthy and at-risk persons aged 65 to 74 years.

Objective: The objective of this study was to assess the health and economic benefits of influenza vaccination in both healthy and at-risk seniors aged 65 to 74 years. Design and setting: Weused administrative claims data from6 consecutive serial cohorts spanning the years 1990 to 1991 through 1995 to 1996. All members of a Twin-Cities managed care organisation who were ≥65 years of age for the respective study year were included in each cohort. Other information obtained included demographic characteristics, baseline comorbidities, prior resource utilisation, and influenza vaccination status. Study outcomes included hospitalisations for pneumonia and influenza and for all respiratory conditions and death. Economic analyses assumed the societal perspective and included both direct and indirect costs. Main outcome measures and results: During the 6 study seasons, there were 100 195 person-periods of observation for persons aged 65 to 74 years. Of these, two-thirds were healthy and one-third had at least one major baseline comorbidity. Influenza vaccination was associated with reductions in hospitalisations for pneumonia and influenza and for all respiratory conditions in both healthy and at-risk groups, although the results did not reach statistical significance among the healthy individuals. Vaccination was also associated with significant reductions in the risk of death for both groups. The economic analysis demonstrated that vaccination against influenza in the base case was associated with direct and total cost savings for both healthy and at-risk seniors aged 65 to 74 years. Conclusion: Influenza vaccination of healthy and at-risk seniors aged 65 to 74 years is associated with substantial health benefits and is cost saving. These findings support age-based vaccination strategies for all persons ≥65 years of age.
Does coronary angiography before emergency aortic surgery affect in-hospital mortality?

Abstract OBJECTIVES To study the relationship between coronary angiography and in-hospital mortality in patients undergoing emergency surgery of the aorta without a history of coronary revascularization or coronary angiography before the onset of symptoms. BACKGROUND In the setting of acute ascending aortic dissection warranting emergency aortic repair, coronary angiography has been considered to be desirable, if not essential. The benefits of defining coronary anatomy have to be weighed against the risks of additional delay before surgical intervention. METHODS Retrospective analysis of patient charts and the Cardiovascular Information Registry (CVIR) at the Cleveland Clinic Foundation. RESULTS We studied 122 patients who underwent emergency surgery of the aorta between January 1982 and December 1997. Overall, in-hospital mortality was 18.0%, and there was no significant difference between those who had coronary angiography on the day of surgery compared with those who had not (No: 16%, n = 81 vs. Yes: 22%, n = 41, p = 0.46). Multivariate analysis revealed that a history of myocardial infarction (MI) was the only predictor of in-hospital mortality (relative risk: 4.98 95% confidence interval: 1.48–16.75, p = 0.009); however, coronary angiography had no impact on in-hospital mortality in patients with a history of MI. Furthermore, coronary angiography did not significantly affect the incidence of coronary artery bypass grafting (CABG) during aortic surgery (17% vs. 25%, Yes vs. No). Operative reports revealed that 74% of all CABG procedures were performed because of coronary dissection, and not coronary artery disease. CONCLUSIONS These data indicate that determination of coronary anatomy may not impact on survival in patients undergoing emergency surgery of the aorta and support the concept that once diagnosed, patients should proceed as quickly as possible to surgery.
Acetylcholine and bradykinin relax intrapulmonary arteries by acting on endothelial cells: role in lung vascular diseases

Acetylcholine and bradykinin produced potent relaxation of isolated canine intrapulmonary arteries contracted by serotonin, norepinephrine, or phenylephrine-provided the endothelium was left intact. Selective mechanical destruction of the endothelium transformed the activity of these substances from vasodilatation to vasoconstriction. Acetylcholine-induced relaxations, in the presence of intact endothelium, could be selectively inhibited competitively by atropine, but could not be inhibited by cyclooxygenase inhibitors, a lipoxygenase inhibitor, adrenergic blocking drugs, or histaminergic antagonists. RElaxations produced by prostacyclin, prostaglandin E1, isoproterenol, papaverine, or histamine H2-receptor agonists were not modified, or attenuated, by selective destruction of pulmonary endothelial cells. These observations might provide insight into the etiology of the increased pulmonary resistance observed in pulmonary hypertension and shock lung.
Partial reduction of disulfide bonds in the hormone-specific subunits of TSH and LH.

Abstract Partial reduction at pH 7.0 of the hormone specific (β) subunit of either bovine thyrotropin or luteinizing hormone with dithioerythritol results primarily in the opening of a single disulfide bridge. The partially reduced subunits were alkylated with [1- 14 C] iodoacetic acid, followed by complete reduction and alkylation with non-radioactive iodoacetic acid. Isolation and degradation of the radioactive tryptic peptides shows that the bond primarily reduced in each β subunit links analogous half-cystine residues in the two sequences (88–95 in TSH-β and 93–100 in LH-β). These results are the first direct evidence of similar disulfide structures in hormone specific subunits of glycoprotein hormones.
Gossyverdurin: A newly isolated pigment from cottonseed pigment glands

The constituents of cottonseed pigment glands were fractionated by the use of column chromatography with DEAE cellulose ion exchanger and silicic acid, and a new green pigment was isolated. The acute oral toxicity of the new pigment was determined using rats as experimental animals. The LD-50 value obtained was 0.66 g/kg of body weight indicating that the new pigment which was named gossyverdurin is the most toxic of any cottonseed pigment so far reported. Gossyverdurin showed absorption maxima at 250, 370, and 560 mμ. Reaction with para-anisidine under the conditions used for the determination of gossypol gave an absorption peak similar to that obtained with gossypol indicating that the new compound is structurally related to gossypol. In addition a second peak at 342 mμ appears on reaction with para-anisidine indicating important structural differences between gossypol and gossyverdurin.
Supercritical Dynamics of Baroclinic Disturbances in the Presence of Asymmetric Ekman Dissipation.

Abstract Finite-amplitude dynamics of baroclinic waves are examined in the presence of asymmetric Ekman pumping at the lower and upper boundaries. Both asymptotic and spectral numerical methods are employed. The resulting amplitude equations yield time evolutions that can lead to an eventual equilibration, a regular perpetual vacillation or a chaotic vacillation depending on the actual values of the supercriticality, the dissipation and the stratification parameters and the fundamental zonal wavenumber. Within the limits of strong bottom dissipation and weak supercriticality, the system always eventually equilibrates and the asymptotic results compare favorably with the numerical results. The vacillation is most likely to occur when the bottom dissipation is weak, supercriticality is strong or the viscous asymmetry is high. Vacillatory final states are possible for up to an order of magnitude larger bottom dissipation than predicted by the symmetric configuration, provided the top dissipation is small in ...
Niche breadth in parasites: an evolutionarily stable strategy model, with special reference to the protozoan parasite Leishmania.

Abstract A parasite's host range essentially defines its niche breadth, which, as foraging theory predicts, is influenced by resource availability. For parasites, the interaction of infection and transmission characteristics with host population dynamics determines host availability. An epidemiological model, involving two host types and describing competition between a “generalist” parasite strain and a related “specialist” strain, is used to examine the interplay among host range, relative host availabilities, and adaptational compromises engendered by increased host range. Results show that the generalist can predominate even when it cannot maintain itself in either host alone, but that the specialist can persist if its reproductive rate attains some threshold relative to either of the generalist's respective rates in its two hosts. The model is in rough, qualitative agreement with observed dynamics of two Leishmania parasite-host systems, and overall results suggest that infection of two species with a common parasite can lead to complex, indirect coevolutionary dynamics.
Building Active Online Interaction via a Collaborative Learning Community

Abstract Online interaction creates a desirable learning situation. Transferring traditional instruction to an online environment usually does not generate effective interaction for learning. This paper discusses theories and practices for an interactive collaborative learning community in an online environment. Three theoretical constructs-interactivity, social context, and technologiesare discussed to provide a theoretical foundation. Effective online interactive strategies and activities, communications, online discussions, technology selections, peer evaluations, team moderations, team projects/presentations, and online learning specialists are recommended to maximize online learning interaction.
Comparison of Grinding and Lapping of Ferrites and Metals

Mechanical finishing of ferrite materials used in magnetic storage systems are found to have a shallow magnetically inactive layer due to residual elastic stress in the surface. The residual stresses in ground and lapped Ni-Zn surfaces are measured and compared with comparable values for steel. Whereas the residual stress in a diamond ground ferrite surface is of predominantly mechanical origin (compressive) that in a conventionally ground steel surface is predominantly of thermal origin (tensile). Methods of reducing the residual stress in a lapped ferrite surface are discussed.
Community structure of insect herbivores in a hybrid system: examining the effects of browsing damage and plant genetic variation

Using three genetic classes of willows, Salix eriocephala, Salix sericea, and their interspecific F1 hybrid, the influence of browsing damage and the importance of genetic class on insect community structure were evaluated. 2. Three-year-old plants grown from seeds generated from controlled crosses were placed in a common garden after a damage treatment was imposed on them (plants were either left undamaged during the previous winter or they had 50% of the previous year's growth removed). Clipping damage caused large increases in mean shoot length for plants. 3. The abundance of eight species of insect herbivores was determined for every plant to evaluate community structure for three genetic classes across the two damage levels. Based on MANOVA, damage treatment had a modest effect on the relative abundance of herbivores (i.e. their proportional representation). In con- trast, dramatic differences were detected among genetic classes for relative abun- dance; in cases where damage treatment influenced relative abundance of herbivores, the importance of genetic class was at least 20-fold greater than that of damage treatment. No interaction between genetic class and browsing treat- ment was detected for community structure. 4. The weak response of the herbivore community to clipping damage, con- trasted tothe large respo nse togenetic class, was very surprising because mean shoot length was greatly altered by damage treatment. These findings, coupled together with previous research, suggest that plant genetic differences can act as the primary basis for herbivore community structure, while the effects of browsing may not be as common.
Structural Insight into p53 Recognition by the 53BP1 Tandem Tudor Domain

Abstract The tumor suppressor p53 and the DNA repair factor 53BP1 (p53 binding protein 1) regulate gene transcription and responses to genotoxic stresses. Upon DNA damage, p53 undergoes dimethylation at Lys382 (p53K382me2), and this posttranslational modification is recognized by 53BP1. The molecular mechanism of nonhistone methyl-lysine mark recognition remains unknown. Here we report a 1. 6-A-resolution crystal structure of the tandem Tudor domain of human 53BP1 bound to a p53K382me2 peptide. In the complex, dimethylated Lys382 is restrained by a set of hydrophobic and cation–π interactions in a cage formed by four aromatic residues and an aspartate of 53BP1. The signature HKKme2 motif of p53, which defines specificity, is identified through a combination of NMR resonance perturbations, mutagenesis, measurements of binding affinities and docking simulations, and analysis of the crystal structures of 53BP1 bound to p53 peptides containing other dimethyl-lysine marks, p53K370me2 (p53 dimethylated at Lys370) and p53K372me2 (p53 dimethylated at Lys372). Binding of the 53BP1 Tudor domain to p53K382me2 may facilitate p53 accumulation at DNA damage sites and promote DNA repair as suggested by chromatin immunoprecipitation and DNA repair assays. Together, our data detail the molecular mechanism of p53–53BP1 association and provide the basis for deciphering the role of this interaction in the regulation of p53 and 53BP1 functions.
Procedures for the Solution of a Finite-Horizon, Partially Observed, Semi-Markov Optimization Problem

This paper presents a finite-time-horizon, partially observed, stochastic optimization problem, where the core process is a controlled, finite-state, discrete-time semi-Markov process. We assume that times of control reset and noise corrupted observations of the core process occur at times of core process transition. The control employed at each time of core process transition is allowed to be functionally dependent on the sample path of the core process only through the history of corrupted observations. Conditions for optimality are stated. We show that the minimum expected cost accrued from a given time t until the terminal time is concave with respect to a sufficient statistic and satisfies a computationally useful functional form. Furthermore, if the set of values that the control vector may assume at each time of control reset is finite, then the expected cost is also piecewise linear with respect to the sufficient statistic. A numerical procedure for the finite-horizon, partially observed, Markov optimization problem is generalized to include the semi-Markov formulation. We give a result that justifies a well known technique for the determination of the optimal cost and an optimal control policy and discuss areas of application.
Aortic Regurgitation: Quantitative Methods by Echocardiography

Quantification of aortic regurgitation (AR) is a common and difficult clinical problem. The severity of regurgitation has traditionally been estimated with the use of contrast aortography, which is impractical as a screening tool or for serial examinations. In the past two decades, Doppler echocardiography has emerged as an important tool in the quantification of AR. Pulsed Doppler mapping of the depth of the regurgitant jet into the left ventricle was one of the initial echocardiographic methods used for this purpose. The slope and pressure (or velocity) half-time of continuous-wave Doppler profiles of regurgitant jets are also useful. These Doppler techniques may be used to determine the regurgitant volume or regurgitant fraction in patients with AR. The use of color Doppler to measure the height (or cross-sectional area) of the regurgitant jet relative to the height (cross-sectional area) of the left ventricular outflow tract is both sensitive and specific in the quantification of AR. More recently, the continuity principle has been used to determine the effective aortic regurgitant orifice area, which increases as AR becomes more severe. Although this is a promising tool, calculation of this value is not yet common practice in most echocardiography laboratories. Although no single echocardiographic technique is without limitations, all have some validity, and it is reasonable to use a combination of them to obtain a composite estimate of the severity of AR.
Modified nucleotides reveal the indirect role of the central base pairs in stabilizing the lac repressor-operator complex

Guanine residues in the lac operator were replaced by 2-aminopurine or purine analogues, pairing the modified nucleotides with C. The observed equilibrium dissociation constants for lac repressor binding to substituted operators were measured in 10 mM Tris, 150 mM KCl, 0.1 mM EDTA, 0.1 mM DTE, pH 7.6 at 25 degrees C. These measurements revealed five positions that destabilized the complex when substituted with either analogue. Two positions, which are related by a 2-fold symmetry, are in the major groove of the operator thought to directly interact with the protein. Three sites were in the central region of the operator. A purine analogue at a sixth site perturbed the local DNA structure and destabilized the complex. Alkylation interference experiments of the 2-aminopurine substituted operators demonstrated that, of the five affected, two substitutions displayed altered phosphate interference patterns at the phosphate adjacent to the substituted base. For these operators, complex formation was measured in different concentrations of KCl to assess the contribution of counterion release to the bimolecular process. The results indicated that both complexes were similar to wild-type, although minor changes were observed. The Kobs of the complex was then measured when 2-aminopurine or purine analogues were paired with uracil nucleotide, a base pair that serves to stabilize the DNA. The introduction of the new base pairs revealed two effects on the bimolecular interaction. For those operator sites that are thought to perturb the interaction directly, the affinity of the complex was weakened to levels observed for the singly-substituted operators. In contrast, the nucleotides of 2-aminopurine paired with uracil positioned in the central region of the operator served to enhance the stability of the complex. The purine-uracil base pair substitution on the other hand had a significant destabilizing effect on the interaction. We propose that the central base pairs modulate binding of the complex by altering the intrinsic properties of the DNA. Two specific attributes are required to achieve the lowest free energy of interaction. The DNA must have two interstrand hydrogen bonds to stabilize the duplex and it must have properties associated with directional bending or unwinding. This analysis does not rule out contributions by direct interactions between the protein and the central region of the operator but underscores how indirect effects play a major role in complex formation in this system.
A Flux-Split Solution Procedure for Unsteady Inlet Flow Calculations

The solution of reduced Navier Stokes (RNS) equations is considered using a flux-split procedure. Unsteady flow in a two dimensional engine inlet is computed. The problems of unstart and restart are investigated. A sparse matrix direct solver combined with domain decomposition strategy is used to compute the unsteady flow field at each instant of time. Strong shock-boundary layer interaction, time varying shocks and time varying recirculation regions are efficiently captured.
Medical costs in workers' compensation insurance.

Abstract We examine whether patients covered by workers' compensation insurance, which covers the cost of medical care for injured workers without cost sharing and with relatively little oversight, are charged more for treatment or receive more services than patients covered by traditional insurance. Our findings indicate that workers compensation recipients are charged more for treatment. This difference persists in individual services — workers' compensation recipients are charged more per X-ray and per examination than other patients. We consider different explanations and argue that price discrimination probably plays a role.
Withdrawal from chronic cocaine administration causes prolonged deficits in L-tryptophan-induced head-twitch response in mice

Abstract Withdrawal from chronic cocaine exposure potentiates the ability of direct 5-HT2A agonists to induce the head-twitch response (HTR) in rodents. This supersensitivity is assumed to be a consequence of cocaine-induced deficits in presynaptic serotonin neurochemistry. The present study utilized the HTR produced by L-tryptophan (TP) to investigate the dose- and time-response effects of cocaine-induced 5-HT deficit. Thus, different groups of mice were injected with cocaine twice daily (0, 0.1, 0.5, 2.5, 5 or 10 mg kg , i.p.) for 7 or 13 days. During HTR testing procedure, at 24 h after last chronic injection, treated-mice received either: 1) no cocaine; 2) their corresponding daily dose; or 3) a 10 mg kg dose. In paradigm 1, the frequency of TP-induced HTR was attenuated in a dose-dependent manner in both chronic cocaine regimens. In paradigm 2, small challenge doses (0.1–2.5 mg kg ) of cocaine in their respective pretreatment groups failed to alter HTR, but larger challenge doses (5 and 10 mg kg ) potentiated the behavior. In paradigm 3, the 10 mg kg challenge dose potentiated the HTR to a similar degree in both chronically exposed vehicle and various cocaine-treated groups in both treatment regimens. Extended withdrawal studies from cocaine exposure (0, 0.5 and 5 mg kg twice daily for 7 or 13 days) indicated attenuations in HTR persisted up to 96 h postcocaine abstinence in paradigm 1, whereas paradigm 2 revealed significant attenuations between 48–72 h for 0.5 mg kg dose; and potentiations for the 5 mg kg dose persisted throughout the 96 h abstinence. In paradigm 3, no significant effect was observed at 96 h abstinence, but the 10 mg kg challenge dose significantly potentiated HTR in chronically exposed 10 mg kg cocaine group 10 days following cocaine abstinence in both exposure regimens. Overall, these results support the notion that chronic cocaine exposure produces prolonged deficits in presynaptic serotonin neurochemistry. Furthermore, serotonergic mechanisms appear to be exquisitely sensitive to chronic administration of both low and high doses of cocaine.
Microwave Gas Breakdown in Tunable Evanescent-Mode Cavity Resonators

Microwave gas breakdown in strongly-coupled evanescent-mode cavity resonators in atmospheric pressure and room temperature is investigated both numerically and experimentally. This high- $Q$ resonator is widely tunable by changing the gap between its loading post and top wall. In this letter, we study the effect of different gap spacings on breakdown characteristics of this resonator. Good agreement is observed between measured breakdown powers and ones by plasma simulations for resonators with gaps of 14.8–51.2 $\mu{\rm m}$ , working in the 6–8.25 GHz frequency range with input breakdown power in the range of 45–48 dBm.
Steam and Gas Turbine Combined Cycle Equipment Currently Available for Natural Gas Pipelines

The high thermal efficiency of the combined steam and gas turbine cycle makes it an attractive candidate for gas pipeline drivers. This paper discusses some aspects of the performance which can be achieved, and the economics associated with this cycle using currently available equipment. One equipment selection has an output capability of over 20,000 hp with a net thermal efficiency of approximately 40 percent. A second equipment selection has an output capability of over 35,000 hp with a net thermal efficiency of approximately 47 percent.Copyright © 1979 by ASME
Cyclic AMP levels in temperature sensitive SV40 transformed cell lines

The cAMP levels of the 3T3 cell line and its transformed derivatives were determined. The level was found to be lower in transformed cell lines than in parental 3T3 and to decrease at confluence in all cell lines tested. SV40 transformed 3T3 cell lines which are temperature sensitive in growth control were found to have lower cAMP levels than 3T3, but these levels were not temperature dependent. Retransformation of these cell lines by murine sarcoma virus did not markedly affect their cAMP levels.
Functions of the 126- and 183-kDa Proteins of Tobacco Mosaic Virus

Tobacco mosaic virus produces two proteins that contain domains similar to the methyltransferase (MT) and helicase (HEL)-like domains of the replicase-associated proteins of other RNA viruses. The more abundant 126-kDa protein contains only the MT and HEL-like domains, whereas the 183-kDa readthrough protein additionally contains the polymerase domain. We examined the functions of these proteins by constructing a bipartite system to express the 126- and 183-kDa proteins from separate RNAs. Mutants expressing the 183-kDa protein recognized promoters for negative- and positive-stranded RNA synthesis, transcribed subgenomic mRNAs, capped RNAs, synthesized proteins, moved cell to cell within the plant, and replicated defective RNAs (dRNAs). The principal function of the 126-kDa protein was to increase the rate of replication approximately tenfold. The 126-kDa protein appeared to function primarily in cis, and production of the 126-kDa protein in trans did not enhance replication of the helper virus. dRNAs producing a functional 126-kDa protein were replicated efficiently by helper viruses that produced only the 183-kDa protein but not by wild-type virus, suggesting that efficient replication required the 183-kDa protein to form a heterodimer with the 126-kDa protein already bound to the target dRNA.
Physical deconditioning as a cause of breathlessness among obese adolescents with a diagnosis of asthma.

Background Obese children frequently complain of breathlessness. Asthma and obesity can both contribute to the symptoms during exercise, and this symptom can contribute to a diagnosis of asthma in these children. Despite the high prevalence of obesity few studies have investigated the cardiopulmonary physiology of breathlessness in obese children with a diagnosis of asthma.
Lattice vibrations in graphite and intercalation compounds of graphite

Abstract The lattice modes of pure graphite can be divided into intraplanar displacements and interplanar displacements. Upon intercalation, the intraplanar vibration frequencies are only slightly shifted, though their Raman and infrared intensities can be greatly changed. These characteristics of the intraplanar vibrational modes are interpreted in terms of symmetry changes associated with intercalation. These symmetry changes give rise to both inplane and c-axis zone folding effects. Detailed results are reported for the Raman spectra of graphite-halogen acceptor compounds and graphite-alkali metal donor compounds. In the case of the graphite-halogen compounds, spectra showing both graphitic modes and intercalate modes are interpreted in terms of this symmetry model. In the case of the alkali metal compounds, the spectra for stage 1 compounds are considered separately from those for higher stage compounds. Particular attention is given both to the broad asymmetric Breit-Wigner high frequency structure and to the sharp doublet structure observed at intermediate frequencies. Infrared spectra of lattice modes in graphite intercalation compounds are reported.
Radiofrequency as a lesioning model in experimental spinal cord injury

Many models have been developed to study spinal cord injury (SCI), such as cryogenic lesioning, hot water injury, scalpel lesioning, compressive trauma using clips, electromechanical devices, extradural cuffs, and weight-drop techniques. In this study, the radiofrequency (RF) lesion was used for inducing an experimental SCI in cats. The neuropathology was correlated with the MRI. In this model, 4 cats were injured at the thoracic spinal cord (T11-T12) with a lesion of 65 degrees C for 1 min using a micromanipulated penetrating RF electrode. The MRI of the lesions after 2, 3, 5, and 6 weeks post-injury as well as the correlative histological changes were obtained. The RF-induced lesion was discrete with little spreading across the spinal cord. There was a good correlation between the histopathology findings and the MRI. We conclude that experimental RF lesioning of the spinal cord can produce a consistent lesion with predictable histopathological changes in experimental animals. A 65 degree C injury for 1 min induced a clinical picture of an incomplete SCI. The RF lesioning should be considered as a new model to study SCI, particularly those with a penetrating component.
Practicing Teachers' Perceptions of Their Preservice Preparation for Mainstreaming

From 1975 through 1986, federal funds were made available in the form of "Dean's Grants" to colleges of education to help prepare teachers to teach mainstreamed handicapped students. Models of prep...
Lipolytic activity of the luteinizing hormone (LH) and of its two subunits.

The lipolytic activity of ovine LH and of its 2 subunits on the white adipose cells has been compared. The minimal effective dose of ovine LH which provokes a release of free fatty acids is 1 × 10-8M when tested on the adipose cells isolated from BALB/c mice. When the lipolytic activity of the subunits of LH are compared to that of the native hormone, it is found that CI subunit is as potent as LH and CII subunit is inactive in the range of concentrations tested. Thus, the white adipose cells isolated from BALB c mice provided an adequate model to study the lipolytic activity of LH. (Endocrinology 89: 571, 1971)
Peptides as receptor ligand drugs and their relationship to G-coupled signal transduction.

Peptides act as effector agents that regulate and/or mediate physiological processes, serving as hormones, neurotransmitters and signal transducing factors. The low molecular weight peptides affect receptor-mediated events, which influence cardiovascular, gastrointestinal and neurocranial systems. While some peptides have been marketed as drugs, many have served as leads or templates for the development of non-peptide drugs that mimic peptide actions. This review presents the advantages and disadvantages of using peptides as drugs that bind as ligands to cell-surface receptors and considers their applications in such events. The value of both the peptides and their mimics is based on their participation in the biomodulation of physiological processes, which frequently employ scaffolding proteins acting in a cascading sequence of protein-to-protein interactions. The peptides bind to G-coupled surface receptors to initiate a signal that is transduced to the interior of the cell through multiple layers of ph...
Modeling and Analysis of a CNG Residential Refueling System

Natural gas has recently been proposed as an alternative fuel for transportation in the United States. Refueling infrastructure is the major technological barrier to the market penetration of passenger compressed natural gas (CNG) vehicles. Currently, there is about one natural gas refueling station every 150 gasoline pumps. Nevertheless, natural gas is widely available in American houses, and thus distributed residential refueling is seen as a viable solution.Generally, residential CNG refueling systems use compressors driven by electric motors. With a potential increase in the number of residential natural gas refueling systems over the next few years, the additional load that this system will introduce on the electric power infrastructure can be significant. In this paper, a system dynamic model of a residential refueling system has been developed and validated against data available in the literature. Ultimately, the model will allow for exploring the impact of residential refueling of CNG vehicles on the electric power infrastructure.Copyright © 2014 by ASME
Vasodilators as first-line therapy for congestive heart failure: A comparative hemodynamic study of hydralazine, digoxin, and their combination☆

Although digitalis and vasodilators both enhance cardiac performance in patients with congestive heart failure, their relative efficacy is unknown. Accordingly, the acute hemodynamic effects of intravenous hydralazine (0.15 mg/kg), digoxin (1.0 mg), and the hydralazine-digoxin combination were evaluated in 14 normotensive heart failure patients at sitting rest, nine of whom were also studied during submaximal upright bicycle exercise. Hemodynamic responses at rest and exercise were similar. Cardiac output and stroke volume rose with both agents, the increase in cardiac output with hydralazine exceeding that with digoxin at rest. Left and right ventricular filling pressures declined equally. Systemic arterial mean pressure and total systemic vascular resistance fell with hydralazine, while, with digoxin, systemic arterial mean pressure increased and total systemic vascular resistance was unchanged. The hydralazine-digoxin combination produced increases in cardiac output and stroke volume that were greater than with either drug alone, and that equalled the sum of the drugs' individual effects; reductions in ventricular filling pressures were similar to the single-drug interventions. Thus, hydralazine is at least as effective as digoxin in improving cardiac function over the short term. Vasodilators may constitute an acceptable alternative to digitalis as initial therapy for congestive heart failure, except where a reduction in systemic arterial pressure is potentially deleterious. Use of combined treatment produces greater increases in cardiac output than with either drug alone, but requires risking the toxicities of two agents.
Pressure broadening of the 83.869 cm−1 rotational lines of OH by N2, O2, H2, and He

Abstract We measured the pressure broadening of the 118.455 cm -1 (3.551 Thz) rotational lines of OH by H 2 , He, N 2 and O 2 . From these measurements, we calculated the pressure broadening of this line by air. The broadening coefficients are 6.06(16) and 10.13(25)×10 -7 cm -1 Pa -1 at 296 and 194 K. We also measured the position of the manifold of lines, with results that are in excellent agreement with a previous accurate determination. The frequency of the strongest component of the transition (F=4←3), and its 2 σ uncertainty is 3 551 185.42(3) MHz.
Capillary force actuators: Modeling, dynamics, and equilibria

Abstract Capillary force actuators provide forces via the alteration of the capillary pressure within a conducting liquid bridge through the application of electrical potential. A dynamic model of a capillary force actuator is developed. Separate models of the fluid/flexured platen and electrodynamics are constructed and linked together via the Young–Lippmann relation. Since the bridge height is small in comparison to the diameter, the liquid slug is shown to have a parabolic velocity profile. The radial pressure variation is then readily determined. Integration of the pressure and summation of the contact line tension term yields the actuation force. Combining this model with the electrodynamics and mechanical components yields a nonlinear model relating applied voltage to platen movement. The equilibria of this equation are determined as a function of voltage and their stability are analyzed. We show that the equilibrium will be stable for displacements exceeding one-third of the nominal bridge height, a greater range than that obtained with parallel plate electrostatic actuators. Depending on actuator design this range may be as large as 7/9th of the nominal bridge height but no larger.
Ultrafast semiconductor laser-diode-seeded Cr:LiSAF regenerative amplifier system

An ultrafast, hybrid mode-locked semiconductor laser-diode system has been used to seed a flash-lamp-pumped Cr:LiSAF regenerative amplifier system, producing subpicosecond pulses with millijoule output pulse energy. This system has the potential to eliminate argon-ion-pumped-based, ultrafast laser systems.
Many‐body perturbation theoretical studies of the dipole moments, polarizabilities, and electron affinities of LiF and BeO

Second‐order many‐body perturbation theory is employed to obtain correlated values of the dipole moments, polarizabilities, and electron affinities of the isoelectronic LiF and BeO molecules. At their equilibrium bond lengths, correlation is found to decrease the dipole moments of LiF and BeO by 0.17 and 0.16 D, respectively, and to increase the mean polarizabilities by 2.35 and 8.81a30, respectively. The net effect of the inclusion of electron correlation is to increase the electron affinity of LiF by 0.02 eV and to decrease that of BeO by 0.13 eV. The redaction of the BeO electron affinity by electron correlation is attributed to the large decrease of the dipole moment from its Hartree–Fock value.
Microfabrication of a high pressure bipropellant rocket engine

A high pressure bipropellant rocket engine has been successfully micromanufactured by fusion bonding a stack of six individually etched single crystal silicon wafers. In order to test the device, an innovative packaging technique was developed to deliver liquid coolant and gaseous propellants to the rocket chip at pressures in excess of 200 atm at temperatures above 300°C. Testing continues on the 1.2 g devices, which have been run to date at a chamber pressure of 12 atm, generating 1 N of thrust, and delivering a thrust power of 750 W.
Scaling Optical Interconnects in Datacenter Networks Opportunities and Challenges for WDM

We review the growing need for optical interconnect bandwidth in data center networks, and the opportunities and challenges for wavelength division multiplexing (WDM) to sustain the “last 2km” bandwidth growth inside data center networks.
Apples to oranges?: A direct comparison between suicide attempters and suicide completers

Abstract Background Suicide attempters and completers may represent different but overlapping groups of distressed individuals. Although depression is related to an increased risk of suicide, the presence of depression may not discriminate suicide attempters from completers. The present study compared suicide attempters and suicide completers on symptoms of depression, the presence of suicide-related variables and stressful life events. Aims The present study sought to identify the key differences between 50 suicide attempters and 50 completers, all diagnosed with a Major Depressive Disorder at the time of their suicidal act. Methods Suicide attempters and family member informants of suicide completers participated in a thorough psychosocial evaluation. To maximize comparisons with completers, suicide attempters were subclassifed based on the lethality of their attempt. Results Suicide attempters and completers were similar on most measures of depressive symptoms. However, suicide completers were significantly more likely to use alcohol or drugs prior to their suicidal act and they were more likely to leave a suicide note. Suicide completers were significantly more likely to have encountered significant job stress and financial problems. Conclusions The present findings have documented several similarities and differences between suicide attempters and suicide completers. Future research may help to clarify the key warning signs that reflect the risk of completed suicide in adults who have been diagnosed with a Major Depressive Disorder.
Ingenious design of tent roosts by Peters's tent-making bat, Uroderma bilobatum (Chiroptera: Phyllostomidae)

All previously known bat tents are made up with single leaves. A new type of tent constructed by Peters's tent-making bat (Uroderma bilobatum) using multiple leaves of young Coccoloba manzanillensis and possibly Genipa americana on Barro Colorado Island, Panama, is reported. Bats constructed the conical tent resembling a tepee by severing the midribs of the lowermost leaves farthest from the tree trunk and those of the upper leaves gradually closer to the trunk. As a result, the upper leaves collapsed on top of the leaves directly below and the whole structure became tightly sealed. Bats used most or all leaves (range 6–14) in a tree, starting almost always from the bottommost leaf. The tent was occupied by a single, or occasionally two, adult male(s) hanging from one of the bottom three leaves. The structural ingenuity of the tent plus its sophisticated repair suggests a complex bat behaviour.
Directional distance functions and slacks-based measures of efficiency

Abstract In this paper we introduce a SBM (slacks-based measure) of efficiency based on directional distance functions. This measure is contrasted with the SBM due to Professor Tone [Tone, K., 2001. A slacks-based measure of efficiency in data envelopment analysis. European Journal of Operational Research 130, 498–509].