cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of Simian Virus 40-Induced Transformation of Hamster Kidney Tissue in Vitro VIII. Induction of Infectious Simian Virus 40 from Virogenic Transformed Hamster Cells by Amino Acid Deprivation or Cycloheximide Treatment

Clones of virogenic simian virus 40 (SV40)-transformed hamster kidney cells were exposed to medium deficient in the essential amino acids leucine, arginine, or methionine. Infectious virus was induced after deprivation periods of from 24 to 32 hr. The highest yields of infectious SV40 were obtained from cultures deprived for 3 to 4 days. Infectious virus was also induced in cells that were treated with the metabolic inhibitor cycloheximide. Pulse labeling experiments revealed that both protein synthesis and deoxyribonucleic acid (DNA) synthesis were inhibited by concentrations of cycloheximide which were effective for virus induction. It is suggested that inhibition of protein synthesis by either amino acid deprivation or by cycloheximide was responsible for the induction of infectious virus from virogenic cells. We postulate that the inhibition of protein synthesis caused a temporary inhibition of DNA synthesis which resulted in the induction of infectious virus.
Variability in the characteristics of pontogeniculooccipital spikes during paradoxical sleep

An important criterion for identifying paradoxical sleep is the presence of a peculiar waveform recorded in the pons, lateral geniculate body, and visual cortex during that sleep state. These waveforms, termed PGO waves, have long been viewed as having large and constant amplitudes, an initial negative deflection in the visual cortex, and not being dependent on the levels of background illumination. Waveforms recorded during wakefulness have different characteristics, and these have been used to differentiate the waking state from paradoxical sleep. The present study demonstrated that most PGO waves have highly variable amplitudes during paradoxical sleep and that only a small fraction conform to the stereotypic wave characteristics of constant and large amplitudes and the presence of initial negative deflections. These findings argue against the criteria commonly used to differentiate PGO waves during paradoxical sleep from the eye movement potentials recorded in wakefulness.
Young children's trust in overtly misleading advice.

The ability of 3- and 4-year-old children to disregard advice from an overtly misleading informant was investigated across five studies (total n = 212). Previous studies have documented limitations in young children's ability to reject misleading advice. This study was designed to test the hypothesis that these limitations are primarily due to an inability to reject specific directions that are provided by others, rather than an inability to respond in a way that is opposite to what has been indicated by a cue. In Studies 1 through 4, a puppet identified as The Big Bad Wolf offered advice to participants about which of two boxes contained a hidden sticker. Regardless of the form the advice took, 3-year olds performed poorly by failing to systematically reject it. However, when participants in Study 5 believed they were responding to a mechanical cue rather than the advice of the Wolf, they were better able to reject misleading advice, and individual differences in performance on the primary task were systematically correlated with measures of executive function. Results are interpreted as providing support for the communicative intent hypothesis, which posits that children find it especially difficult to reject deceptive information that they perceive as being intentionally communicated by others.
The crystal structure of beta-platinum dioxide

Abstract β-PtO 2 crystallizes as the orthorhombic CaCl 2 -type structure with a = 4·488(3) A , b = 4·533(3) A , and c = 3·138(2) A . The oxygen coordinates are found to be: x = 0·281 and y = 0·348. This leads to two long PtO bonds of 2·02 A, four short bonds of 1·98 A, and a mininum oxygen-oxygen approach of 2·40 A. The Pt(IV) radius is 0·63 A. A comparison of the PtO 2 structure with the rutile form of TiO 2 is presented.
Cyanide release from nitroprusside in the isolated, perfused, bloodless liver and hindlimbs of the rat.

Abstract When sodium nitroprusside in artificial medium was perfused through the isolated liver and hindlimbs of a rat at the near physiological flow rate of 8.5 ml min −1 , free cyanide was found in the perfusate. The liver reached a steady-state ratio of cyanide released/nitroprus-side perfused of about 1.5 (or approximately 30% of the total nitroprusside cyanide) within 15 min, and maintained that rate for about 1.5 hr. In the hindlimbs cyanide was released at a much slower rate (7.5 to 18.8% of the total), and the release did not achieve a steady state even after 1.5 hr. Even after small corrections for cyanide extraction by both tissues, the rate of cyanide release by either tissue was probably more rapid than that resulting from static incubations in blood.
Computationally efficient, numerically exact design space derivatives via the complex Taylor's series expansion method

Abstract Within numerical design optimization, discrete sensitivity analysis is often used to estimate the derivative of an objective function with respect to the design variables. Discrete sensitivity analysis estimates these derivatives by taking advantage of additional derivative information available in an implicit computational fluid dynamics (CFD) solver of the discretized governing partial differential equations. The key benefits of steady-state discrete sensitivity analysis are its computational efficiency and numerical accuracy. More recently, the complex Taylor's series expansion (CTSE) method has been used to generate these design space derivatives to machine accuracy, by analyzing a complex perturbation of the objective function. For fortran codes, this method is quite easy to implement, for both implicit and explicit codes; unfortunately, the CTSE method can be quite time consuming, because it requires a complex solution of the governing partial differential equations. In this paper, the authors demonstrate that the direct formulation of discrete sensitivity analysis and the CTSE method solve the same iterative sensitivity equation , which sheds light on the most efficient use of the CTSE method. Finally, these methods are demonstrated via application to numerical simulations of one-dimensional and two-dimensional open-channel flows.
A note on Bjerkne's hypothesis for North Atlantic variability

Abstract On decadal time-scales the historical surface temperature record over land in the Northern Hemisphere is dominated by polar amplified variations. These variations are coherent with SST anomalies concentrated in the Northwest Atlantic, but extending with lesser amplitude into the North Pacific as well. Bierknes suggested that multi-year SST anomalies in the subpolar North Atlantic were due to irregular changes in the intensity of the thermohaline circulation. In support of the Bjerknes hypothesis there is evidence that winter overturning in the Labrador Sea was suppressed for a brief period from 1967–1969 by a cap of relative fresh water at the surface. Cause and effect are unclear, but this event was associated with a marked cooling of the entire Northern Hemisphere. The difference in SST averaged over the Northern Hemisphere oceans and SST averaged over the Southern Hemisphere oceans from the equator to 40°S is coherent with Sahel summer rainfall on decadal time scales. Empirical evidence is supported by numerical experiments with the British Meteorological Office atmospheric climate model which simulate augmented monsoonal rainfall in the Sahel region of Africa in response to realistic warm SST anomalies in the Northwest Atlantic. A coupled ocean-atmosphere global model exhibits two equilibrium climate states. One has an active thermohaline circulation in the North Atlantic and the other does not. The two climate states provide an extreme example which illustrates the type of large scale air sea interaction Bjerknes visualized as a mechanism for North Atlantic climate variability on decadal time-scales.
Compression standards roles in image processing: case study

With the rapid spread of image and video processing applications and the further development of multimedia technologies, compression standards become more and more important every day. This study was conducted to investigate the role of compression standards in image processing. Digital watermarking algorithm for securing multimedia application is considered one of the most important applications heavily rely on compression standards. It was selected to perform our experimental study by employing wavelet and JPEG compression standards. An analysis of the experiment results indicated that the wavelet outperform JPEG compression standard and applications implemented wavelet have better performance than those implemented JPEG.
Extended curettage for benign bone lesions

Benign bone lesions present a unique challenge to the practicing orthopaedist. They are a not uncommon problem that often present in the pediatric or young adult population. The most common diagnoses include giant cell tumor of bone, aneurysmal bone cysts, unicameral (simple) bone cysts, metaphyseal fibrous defects, and fibrous dysplasia. Appropriate surgical intervention must balance acceptable recurrence rates and surgical morbidity in line with their benign diagnosis. Historically, early surgical invention had unacceptably high recurrence rates. A more aggressive surgical approach to these lesions significantly decreased recurrence rates but surgical morbidity rose to levels considered unacceptable for benign lesions. Extended curettage offers a satisfactory compromise with decreased recurrence rates and significantly less surgical morbidity. Extended curettage is a technique of intralesional excision where the margins of the excision are extended by a surgical, chemical, or thermal adjuvant. Adjuvant options include phenol, liquid nitrogen, high-speed burr, cementation with polymethylmethacrylate, and argon-beam coagulation. The technique described here uses a combination of high-speed burr, argon-beam coagulation, and cementation to treat benign bone lesions resulting in an acceptable recurrence rate and acceptable rate of surgical morbidity.
Identification of potential biomarkers of exposure to di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH), an alternative for phthalate plasticizers

Identification of potential biomarkers of exposure to di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH), an alternative for phthalate plasticizers
Vascular reactivity in systemic arterial hypertension.

Abstract 1. 1. In most systemic vascular beds and in the systemic circulation as a whole, vascular reactivity to vasoactive substances acting directly or indirectly on the sympathetic neural and vascular receptor complex is increased in hereditary essential hypertension. 2. 2. Since such increased reactivity is present early in the course of the disease and even in essential prehypertension and is associated with certain abnormalities of catecholamine metabolism, it is probably an etiologic factor. 3. 3. Since 10 to 15 per cent of the population has or will have hereditary essential hypertension and since this disease predisposes to renovascular hypertension and pyelonephritis and probably anxiety hypertension and primary as well as secondary hyperaldosteronism, mixed cases of essential hypertension together with these special types of hypertension comprise from 30 to 50 per cent of these special cases. In the pure cases, however, digital vascular reactivity and catecholamine metabolism are normal. 4. 4. Hereditary essential hypertension is probably caused by an abnormal gene or genes producing an abnormal protein or proteins which either directly or indirectly affect the systemic sympathetic neural and/or vascular receptor-contractile sites.
Efficient molecular surface rendering by linear-time pseudo-Gaussian approximation to Lee–Richards surfaces (PGALRS)

The PGALRS (pseudo-Gaussian approximation to Lee–Richards surfaces) algorithm is discussed. By modeling electron density with unphysical pseudo-Gaussian atoms, the Lee–Richards surface can be approximated by a contour level of that density in time approximately linear in the number of atoms. Having that contour level, the atoms and residues closest to that surface can be identified in average time O[n2/3log(n)] using a NearTree-based nearest neighbor search. If a high-quality Lee–Richards surface is required, then, as a final stage, one of the standard Lee–Richards algorithms can be used but considering only the previously identified surface residues; the typical cost is thereby reduced to O[n2/3log(n)], making the overall average time for all the steps O(n). For very large macromolecules, such a reduction in computational burden may be essential to being able to render a meaningful molecular surface. This approach extends the feasible range of application for existing molecular surface software, such as MSMS, to larger macromolecules, especially to macromolecules with more than 50 000 atoms, and can be used as a starting point for surface-based (as opposed to backbone-based) motif identification, e.g. using ProMol.
A rapid, quantitative determination of total and free cholesterol with anthrone reagent

Abstract A simple, rapid microcolorimetric determination for total and free 3β-hydroxy sterols in serum and tissues has been described. Following extraction of total sterols and saponification of the esterified fraction by established procedures, the sterol is precipitated in 15 min at 45°C as the digitonide using 10% aluminum chloride. The isolated sterol digitonide is purified by twice recrystallizing from methanol-10% aluminum chloride (1 : 1), each step requiring 20 min at 45°C. The precipitate is washed with acetone and suspended in glacial acetic acid, and the digitonin moiety is determined with a stable anthrone reagent. Multiple analyses of sterol concentrations as low as 15–20 μg are routinely determined with an accuracy comparable to the method of Sperry and Webb, and with a greater sensitivity and precision than obtained with the latter method.
Urinary concentrations of metabolites of pyrethroid insecticides in the general U.S. population: National Health and Nutrition Examination Survey 1999-2002.

BackgroundPyrethroid insecticides are the most commonly used residential insecticides in the United States.ObjectivesOur objective was to assess human exposure via biomonitoring to pyrethroid insec...
Characterization of human immunodeficiency virus type-1 from HIV-1 seropositive cases with undetectable viremia.

Abstract Background: Human immunodeficiency virus type 1 (HIV-1) viral load has become a standard of care among HIV-1-infected patients; however, a small number of patients have undetectable viral load even though they have never been treated. Methods: By using RT-PCR and DNA-PCR, and followed by sequencing and phylogenetic analyses, a detailed molecular characterization was carried out from five HIV-1-seropositive patients who had undetectable viral load by commercially available ultrasensitive viral load assays. Results: Of the four patients whose plasmas were available, viral RNAs were detected in three of them by using an in-house RT-PCR in at least one of the three regions (integrase, protease or env gp41). The fourth patient had positive RT-PCR signals in these regions only when RNA isolated from the supernatant of cocultivated patient PBLs with PHA-stimulated HIV-1 negative donor PBLs was used. Further analysis of DNA extracted from the PBMCs revealed that four of the five patients had detectable proviral sequences in at least two of the three regions. The fifth patient had only positive PCR results in all three regions when DNA isolated from PHA-stimulated patient’s PBLs was used. Phylogenetic analysis of protease and env gp41 regions revealed that three patients were infected with subtype B viruses while the remaining two patients were infected with subtype C and CRF02_AG viruses. These subtypes coincided with geographic origin and known molecular epidemiology of HIV-1 infection. Conclusion: These data provide evidence that both subtype B and non-B HIV-1 infection can result in undetectable viral load in HIV-1-infected patients and that efforts should continue to further characterize these viruses.
The Structure of Rapidly Rotating Late-Type Spiral Galaxies. I. Photometry, H I, and Optical Kinematics

We present I-band photometry, long-slit optical spectroscopy, and new aperture synthesis H I observations for eight late-type spiral galaxies with rotation velocities in the range 243 km s-1 Vrot 308 km s-1. The sample will be used to study the structure and angular momentum of disks at the high-mass end of the spiral galaxy population; here we discuss the basic properties of these fast rotators and derive hybrid optical/H I rotation curves for each. Despite the presence of H I warps and low-mass companions in many systems, their kinematics are regular and there is excellent agreement between optical and H I tracers near the optical radius ropt. At high inclinations at which projection effects are negligible, the sample galaxies exhibit flat, featureless rotation curves out to their last measured points at 1.7ropt-3.5ropt. The intermediate-inclination systems are also consistent with a constant rotation amplitude for r 0.5ropt. We therefore find no evidence for declining rotation curves at the high-mass end of the late-type spiral galaxy population. Combining our data with the compilation of spiral galaxies with reliable outer H I kinematics from the work of Casertano and van Gorkom, we find no convincing trends between logarithmic outer rotation curve slopes and rotation amplitudes or surface brightnesses for galaxies with Vrot 220 km s-1. Correlations between these slopes and morphological types or disk scale lengths are also marginal in this regime.
A comprehensive examination of the wealth effects of recent stock repurchase announcements

The main purpose of this paper is to examine the wealth effect of stock repurchase announcements using a sample of 11,862 repurchase programs announced during 1994–2007. The results of several recent industry surveys indicate that managerial motivations for repurchasing shares may have changed in recent years. To better understand the reasons for repurchasing shares we classify our sample in various ways—by year, by the method used for repurchasing shares, and by the stated purpose of the program. We find that the median size of firms repurchasing shares has increased dramatically recently, and concomitantly, the announcement returns have declined. Signaling undervaluation of share prices appears to become less important than previously assumed. While smaller firms signal undervaluation using open market repurchases, tender offers are chosen to enhance shareholder values by other means.
Current and potential applications of enzyme infusion in the food industry

Enzyme infusion can alter the texture, flavor and other sensory attributes of foods. A limitation of this process in the case of intact fruit and vegetables is the molecular size of the enzyme; some sort of driving force is required to facilitate entry of the enzyme into intact tissues. Pressure-assisted infusion and vacuum-assisted infusion of fresh tissues and imbibition of dried tissues have been used to effect enzyme infusion of fruit and vegetables. At least one application of enzyme infusion, which utilizes pectinases to peel fresh citrus fruit, has been commercialized. The application of enzyme infusion to alter the texture or flavor of fruit and vegetables has also been described. This article reviews these successful applications, and other potential uses of this technology.
Optical neural networks using smectic liquid crystals

We demonstrate both nematic and ferroelectric liquid crystal SLM's in two separate optical connectionist machines on which two layer neural network algorithms are executed. An analysis of their system performance with respect to non-ideal operation of the component parts is presented; the analysis being carried out with the aid of a computer simulation. A direct comparison between the two machines is then made demonstrating the improved performance of the compact ferroelectric liquid crystal based machine.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Convergent Validation of the Kohlman Evaluation of Living Skills as a Screening Tool of Older Adults' Ability to Live Safely and Independently in the Community

Abstract Burnett J, Dyer CB, Naik AD. Convergent validation of the Kohlman Evaluation of Living Skills as a screening tool of older adults' ability to live safely and independently in the community. Objective To evaluate the convergent validity of the Kohlman Evaluation of Living Skills (KELS) to screen older adults' ability to live safely and independently. Design Cross-sectional study correlating KELS with components of a Comprehensive Geriatric Assessment. Setting Participants' homes. Participants Community-dwelling older adults (N=200) 65 years and older including 100 persons referred by Adult Protective Services (APS) and 100 ambulatory patients matched on age, race, sex, and socioeconomic status. Interventions In-home comprehensive assessment. Main Outcome Measures KELS, Geriatric Depression Scale (GDS), modified Physical Performance Test (mPPT), Mini-Mental State Examination (MMSE), Knee Extensor Break Test, Executive Cognitive Test (EXIT25), executive clock-drawing test (CLOX) 1 and 2, and an 8-foot walk test. Results Older adults with abnormal KELS scores performed significantly worse on all tests except for the Knee Extensor Break Test. Accordingly, among the entire group, the KELS correlated with measures of executive function (EXIT25, r =.705, P r =−.629, P r =−.508, P r =.318, P r =−.472, P r =−.068, P =.456). Among those referred by APS, the KELS failed to correlate with only the 8-foot walk test ( r =.175, P =.153) and GDS ( r =.080, P =.450). Conclusions This study demonstrated the convergent validity of KELS with a battery of cognitive, affective, executive, and functional measures often used to determine older adults' ability to live safely and independently in the community. KELS may be a valid and pragmatic alternative to screen for the capacity to live safely and independently among older adults.
Selenium and cancer: effects of selenium and of the diet on the genesis of spontaneous mammary tumors in virgin inbred female C3H/St mice.

Inbred female C3H/St mice exhibit the normal incidence of spontaneous mammary adenocarcinoma of 80~100% if they are maintained on a standard commercial laboratory diet containing 0.15 ppm of selenium with meat and dried skimmed milk as major sources of protein. The tumor incidence drops to 42% if animals of the same strain are kept on a diet containing 0.45 ppm of selenium, with fishmeal as the main source of protein. The tumor incidence declines further to 25, 19 and 10% if the animals in addition receive 0.1, 0.5, and 1.0 ppm of selenium in the drinking water. Selenium supplementation at these levels has no noticable adverse effects on weight-gains and survival of the mice. Selenium supplemented groups of animals also remained tumor-free for
Femorofemoral bypass to relieve acute leg ischemia during intra-aortic balloon pump cardiac support

Abstract This study reports our experience with 10 patients who underwent the emergent construction of a femorofemoral bypass graft to salvage an acutely ischemic lower extremity following the insertion of a transfemoral intra-aortic balloon pump catheter. All patients had excellent resolution of the ischemia and salvage of the extremity. Half of the procedures were done at the bedside with the remainder performed in the operating room. No long-term infections or ischemic sequelae resulted from the procedures in the nine patients available for long-term follow-up. The use of femorofemoral bypass grafting is, therefore, recommended in patients with severe ipsilateral limb ischemia who are dependent on an intra-aortic balloon pump to prevent extremity tissue loss as well as the systemic metabolic manifestations of ongoing tissue ischemia and necrosis. Patient selection, technical considerations, and postoperative management are discussed. (J VASC SURG 1986;3:351-4.)
Polycyclic Aromatic Hydrocarbons (PAHs) Mediate Transcriptional Activation of the ATP Binding Cassette Transporter ABCB6 Gene via the Aryl Hydrocarbon Receptor (AhR)

Liver is endowed with a mechanism to induce hepatic cytochromes P450 (CYP450s) in response to therapeutic drugs and environmental contaminants, leading to increased detoxification and elimination of the xenobiotics. Each CYP450 is composed of an apoprotein moiety and a heme prosthetic group, which is required for CYP450 activity. Thus, under conditions of CYP450 induction, there is a coordinate increase in heme biosynthesis to compensate for the increased expression of CYP450s. ABCB6, a mitochondrial ATP binding cassette transporter, which regulates coproporphyrinogen transport from the cytoplasm into the mitochondria to complete heme biosynthesis, represents a previously unrecognized rate-limiting step in heme biosynthesis. However, it is not known if exposure to drugs and environmental contaminants induces ABCB6 expression, to assure an adequate and apparently coordinated supply of heme for the generation of functional cytochrome holoprotein. In the present study, we demonstrate that polycyclic aromatic hydrocarbons (PAHs), the widely distributed environmental toxicants shown to induce porphyrin accumulation causing hepatic porphyria, up-regulate ABCB6 expression in both mice and humans. Using siRNA technology and Abcb6 knock-out mice, we demonstrate that PAH-mediated increase in hepatic porphyrins is compromised in the absence of ABCB6. Moreover, in vivo studies in aryl hydrocarbon receptor (AhR) knock-out mice demonstrate that PAH induction of ABCB6 is mediated by AhR. Promoter activation studies combined with electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrate direct interactions between the AhR binding sites in the ABCB6 promoter and the AhR receptor, implicating drug activation mechanisms for ABCB6 similar to those found in inducible cytochrome P450s. These studies are the first to describe direct transcriptional activation of both mouse and human ABCB6 by xenobiotics.
A surface tension equilibrium study of human serum in atherosclerosis.

The rate of attainment of a static surface tension equilibrium by human blood serum was investigated. In general serum from atherosclerotic individuals tends to reach a static surface tension value...
Atypical ductal hyperplasia: improved accuracy with the 11-gauge vacuum-assisted versus the 14-gauge core biopsy needle.

Background Percutaneous stereotactic core needle biopsy (CNB) has become the primary diagnostic modality for evaluating nonpalpable, mammographically detected breast lesions. Atypical ductal hyperplasia (ADH) uncovered by CNB confers a significant risk of harboring an occult malignancy in the excisional biopsy specimen; therefore, we sought to determine the benefits of upsizing biopsy needles from 14- to 11-gauge.
Role of robotic-assisted surgery in benign esophageal diseases

Laparoscopic treatment of benign esophageal conditions is technically complex with several inherent limitations. Robotic-assisted surgery provides technical improvement and helps to overcome some of these limitations. We therefore report a single surgeon’s experience in management of benign esophageal diseases by robotic-assisted surgery. Over a period of 8 consecutive years, a retrospective chart review was performed of 105 patients who underwent robotic-assisted surgery for benign esophageal diseases by a single surgeon. Demographic data and outcome measures were studied. The robotic-assisted procedures included 85 Nissen fundoplications with and without mesh repair, 12 Heller myotomies and eight para-esophageal hernia repairs. The mean total operating time was lowest for the Nissen group (94 min) and highest for the para-esophageal group (183 min). Operating time decreased from a mean of 105 min in the first 20 cases to 84 min in the last 20 cases for the Nissen group (P = 0.014). The mean length of stay was 1.3, 1.6, 1.5 and 4.8 days for the groups, respectively. Persistent symptoms of dysphagia/reflux/dysphonia requiring further investigation were seen in nine (8 %) of these patients. Two of these patients required repeat Nissen fundoplication in the mesh group. Our complication rate, total operating time and length of stay for robotic-assisted benign esophageal surgery are comparable to those reported in the literature. When performed by an experienced surgeon, robotic-assisted surgery is safe and effective in the management of benign esophageal diseases.
Predictions of vigorous ignition dynamics for a packed bed of solid propellant grains

Abstract This work represents the key results of a research project to predict the pressure wave propagation and flame spreading in a porous propellant charge ignited at one end by a high explosive initiator. The predictions attempted to model controlled laboratory tests with large grain M30 propellant confined in a cylinder and ignited by detonating an explosive disc at the open end. It was predicted that the magnitude of the initiator mass discharge rate determines the convective flame front speed and the pressure wave propagating into the propellant bed.
Consistent dynamics suggests tight regulation of biophysical parameters in a small network of bursting neurons

The neuronal firing patterns in the pyloric network of crustaceans are remarkably consistent among animals. Although this characteristic of the pyloric network is well-known, the biophysical mechanisms underlying the regulation of the systems output are receiving renewed attention. Computer simulations of the pyloric network recently demonstrated that consistent motor output can be achieved from neurons with disparate biophysical parameters among animals. Here we address this hypothesis by pharmacologically manipulating the pyloric network and analyzing the emerging voltage oscillations and firing patterns. Our results show that the pyloric network of the lobster stomatogastric ganglion maintains consistent and regular firing patterns even when entire populations of specific voltage-gated channels and synaptic receptors are blocked. The variations of temporal parameters used to characterize the burst patterns of the neurons as well as their intraburst spike dynamics do not display statistically significant increase after blocking the transient K-currents (with 4-aminopyridine), the glutamatergic inhibitory synapses (with picrotoxin), or the cholinergic synapses (with atropine) in pyloric networks from different animals. These data suggest that in this very compact circuit, the biophysical parameters are cell-specific and tightly regulated.
113Cd NMR binding studies of Cd-fulvic acid complexes: Evidence of fast exchange

The binding of Cd 2+ to Suwannee River fulvic acid is studied using potentiometric methods and 113 Cd NMR spectroscopy. The potentiometric results indicate 6.4 and 1.2 mequiv/g carboxylic and phenolic acid groups for the Suwannee River fulvic acid standard. At pH 6.4, the fraction of of the carboxylic acid groups that are deprotonated is 0.89. The observed 113 Cd NMR chemical shift changes with constant Cd 2+ concentration and varying fulvic acid concentration at pH 6.4 are consistent with the fast exchange model. Analysis of the 113 Cd NMR chemical shift data using a Scatchard plot yields a conditional binding constant of 6.7 x 10 2 mL/mg. A number-average apparent molecular weight of 800 g/mol, gives a value of 0.9 for the fraction of the fulvic acid carboxylate sites that are bound to cadmium and a cadmium-fulvic acid complex formation constant of 5.4 x 10 2 M -1 .
The anharmonic Urey-Bradley force field; the computational algorithm and its application to CF4

Abstract In the Urey-Bradley force field, forces between non-bonded atoms are included along with the valence-bond stretching force constants and the valence-angle deformation force constants. The forces between non-bonded atoms are represented by a Lennard-Jones function. The well-known computational difficulties associated with the Urey-Bradley force field, difficulties which compound seriously when one considers the anharmonic terms in the force field, are recognized as a special treatment of a particular redundant coordinate. These computational difficulties are all avoided in the algorithm described in this paper; the redundant coordinates are handled by first transforming the potential-energy function, including linear terms, into Cartesian space. The well-known ‘tree’ redundancy in the six angles about the central carbon atom is also treated properly. Numerical values of the anharmonic normal-coordinate force constants and the anharmonic coefficients are derived.
Recovery from punishment related to movement and punishment severity

Thirty-two Sprague-Dawley rats were punished for barpressing, using two intensities orthogonal to two durations of shock, until a 5-min nonresponse criterion was reached. Speed of recovery was significantly correlated with proximity to the response manipulandum during the nonresponse criterion period, but independent of the intensity and duration of shock used. Intensity and duration of shock combine to determine severity of punishment.
Evaluation of an enkephalin analog in men with castor oil–induced diarrhea

This study was a parallel, double-blind, placebo-controlled evaluation of acute doses of nifalatide, an enkephalin analog, in subjects with castor oil–induced diarrhea. Seventy-two subjects completed the study. The time to first stool after castor oil administration was significantly greater after the 16 and 48 mg doses of nifalatide as compared with placebo dosing. The same doses of nifalatide also decreased the overall stool frequency, the frequency of abdominal cramping, and the incidence of nausea and vomiting. There were no clinically significant, drug-related changes in the physical examination results, ECG, vital signs, or clinical laboratory parameters. The only increased adverse experiences that appeared to be related to the drug were dizziness and mild dry mouth. Clinical Pharmacology and Therapeutics (1986) 39, 40–42; doi:10.1038/clpt.1986.7
A dual-capacity model of communication media choice in organizations

Most previous research concerning communication media choke in organizations has stressed the capacity of media to convey data. More recently, scholars have examined the capacity of media to convey and manifest meaning. Rarely have both functions been considered concurrently. In this artcle, a model is proposed that not only permits the simultaneous examination of these two functions but reflects that media use is influenced by characteristics of the task, individual and organizational capability constraints, and normative factors. By exploring the implications of this expanded dual-capacity perspective, a more encompassing theory of the determinants of communkation media use in organizations is proposed.
Installation Requirements for Small Gas Turbine Engines

Allison currently has over 20,000 Model 250 small gas turbine engines operating throughout the world in a variety of turboprop and turboshaft installations. The experience base has contributed to the understanding and development of small engine installation requirements. Some of the critical interface systems will be reviewed to highlight some of the small engine considerations of engine installation design.Copyright © 1985 by ASME
The National Food and Nutrient Analysis Program: A decade of progress

The National Food and Nutrient Analysis Program (NFNAP) was designed to expand the quantity and improve the quality of data in the United States Department of Agriculture (USDA) food composition databases through the collection and analysis of nationally representative samples of foods and beverages. This paper describes some of the findings from the NFNAP and its impact on the food composition databases produced by USDA. The NFNAP employs statistically valid sampling plans, comprehensive quality control, and USDA analytical oversight as part of the program to generate new and updated analytical data for food components. USDA food consumption and composition data were used to target those foods that are major contributors of nutrients of public health significance to the U.S. diet (454 Key Foods). Foods were ranked using a scoring system, divided into quartiles, and reviewed to determine the impact of changes in their composition compared to historical values. Foods were purchased from several types of locations, such as retail outlets and fast food restaurants in different geographic areas as determined by the sampling plan, then composited and sent for analysis to commercial laboratories and cooperators, along with quality control materials. Comparisons were made to assess differences between new NFNAP means generated from original analytical data and historical means. Recently generated results for nationally representative food samples show marked changes compared to database values for selected nutrients from unknown or non-representative sampling. A number of changes were observed in many high consumption foods, e.g. the vitamin A value for cooked carrots decreased from 1,225 to 860 RAE/100g; the fat value for fast food French fried potatoes increased by 13% (14.08 to 17.06 g/100g). Trans fatty acids in margarine have decreased as companies reformulate their products in response to the required addition of trans fatty acids content on the nutrition label. Values decreased from 19.7 g/100 in 2002 to 14.8 g/100 in 2006 for 80%-fat stick margarines and to 4.52 g/100 g for 80%-fat tub margarines. These changes reflect improved strategies for sampling and analysis of representative food samples, which enhance the reliability of nutrient estimates for Key Foods and subsequent assessments of nutrient intake.
Real-Time Competitive Environments: Truthful Mechanisms for Allocating a Single Processor to Sporadic Tasks

In a non-competitive environment, sporadic real time task scheduling on a single processor is well understood. In this paper, we consider a competitive environment comprising several real-time tasks vying for execution upon a shared single processor. Each task obtains a value if the processor successfully schedules all its jobs. Our objective is to select a feasible subset of these tasks to maximize the sum of values of selected tasks. There are algorithms for solving this problem in non-competitive settings. However, we consider this problem in an economic setting in which each task is owned by a selfish agent. Each agent reports the characteristics of her own task to the processor owner. The processor owner uses a mechanism to allocate the processor to a subset of agents and to determine the payment of each agent. Since agents are selfish, they may try to manipulate the mechanism to obtain the processor. We are interested in truthful mechanisms in which it is always in agents' best interest to report the true characteristics of their tasks. We design exact and approximate truthful mechanisms for this competitive environment and study their performance.
Selective serotonin reuptake inhibitors modify the effect of beta-blockers on long-term survival of patients with end-stage heart failure and major depression.

Background Major depression (MD) is a key feature in heart failure (HF), and it is unclear whether common antidepressive medications interact with cardiovascular drugs used for the treatment of patients with MD and HF, affecting their efficacy. We examined the impact of MD on long-term survival of patients with end-stage severe HF. We also evaluated the interaction between antidepressive medication and beta-blockers on the clinical outcome of these patients. Methods and results The study population consisted of 250 patients with end-stage severe HF. Sixty-one percent of these patients suffered MD and were receiving selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), or tricyclic antidepressants (TCA). All patients were followed prospectively for 18 months. The primary end point was cardiovascular death. At baseline, patients with severe MD had higher serum interleukin 6 (P Conclusions MD is an independent predictor of cardiovascular death in patients with end-stage HF. beta-blockers are associated with lower cardiovascular mortality in patients with end-stage HF and depression only when they are combined with SSRIs.
Synthesis of nuclear acidic proteins in density-inhibited fibroblasts stimulated to proliferate.

Previous work from this laboratory (Rovera and Baserga, 1971) has shown that, when density-inhibited WI-38 human diploid fibroblasts are stimulated to proliferate by a change of medium, the synthesis of nuclear acidic proteins increases within 30 minutes after stimulation; several hours before DNA synthesis begins to increase. Similar results have now been obtained with density-inhibited 3T6 mouse fibroblasts, also stimulated by a change of medium. Gel electrophoretic analysis of nuclear acidic proteins in both WI-38 human diploid fibroblasts and 3T6 mouse fibroblasts stimulated to proliferate indicates that the increased synthesis of nuclear acidic proteins is limited to certain classes of proteins while other classes are totally unaffected. The increase in nuclear acidic proteins synthesis is inhibited when WI-38 cells or 3T6 cells are stimulated in the presence of 5-azacytidine (10 μg/ml), a treatment which also inhibits the subsequent stimulation of DNA synthesis. These results, confirming and extending similar findings previously reported in other models of stimulated DNA synthesis, lend further support to the hypothesis that nuclear acidic proteins may play a critical role in the control of DNA synthesis and cell division in mammalian cells.
Eruption at Deception Island, Antarctica, August 1970

The eruption in August 1970 in the South Shetland Islands, Antarctica, was the most violent explosion that has occurred over the past four years of recent activity. Fine-grained salty tephra of mugearite composition was spread over the northern half of the 14 km-wide island from 5 maar-type marine craters and 7 land vents. One land crater was developed in glacial ice. Further activity is anticipated.
Mechanisms controlling the chemical composition of lakes and rivers: Data from Africa

Data for natural lakes, rivers, and springs in intertropical Africa indicate that the chemical compositions of these waters are controlled primarily by rock dominance (weathering reactions) and the evaporation-crystallization process (evaporative concentration and calcite precipitation). There are minor deviations from the primary pattern observed in Africa and elsewhere. They usually occur as a result of contamination by cyclic salts or salts ultimately derived from ancient lakes or oceans.
The Effect of Chronic Furosemide Administration on Urinary Calcium Excretion and Calcium Balance in Growing Rats

The Effect of Chronic Furosemide Administration on Urinary Calcium Excretion and Calcium Balance in Growing Rats
A case report of bilateral autoenucleation and its prevention.

Purpose: To report a case and review both the ophthalmic and psychiatric literature to document the pattern of this self-mutilation and review prevention techniques. Design: Case report and retrospective review. Interventions: Surgical repair of the orbits in a patient who autoenucleated both eyes. Main Outcome Measures: To determine methods to prevent self-destructive behavior. Results: Up to 75% of these acts are performed by psychiatric inpatients as a form of focal suicide. Methods to prevent self-inflicting behavior include differential reinforcement, boxing gloves, soft cotton gloves, a bubble helmet, facial screening, electrical stimulation, and tarsorraphy. Conclusions: Prevention of autoenucleation requires early identification of susceptible subjects and timely initiation of preventive measures.
Effect of the degree of polar mismatching on traffic jam formation in fast axonal transport.

This paper simulates an axon with a region of reversed microtubule (MT) polarity, and investigates how the degree of polar mismatching in this region affects the formation of organelle traps in the axon. The model is based on modified Smith–Simmons equations governing molecular-motor-assisted transport in neurons. It is established that the structure that develops as a result of a region with disoriented MTs consists of two organelle traps, the trap to the left of this region accumulates plus-end-oriented organelles and the trap to the right of this region accumulates minus-end-oriented organelles. The presence of such a structure is shown to inhibit the transport of organelles down the axon. The degree by which the transport of organelles is inhibited depends on the degree of polar mismatching of MTs in the region between MT traps. Four cases with a different degree of polar mismatching are investigated.
Core physics competencies for proton therapy training of radiation oncology and medical physics residents and fellows.

Core Physics Competencies for Proton Therapy Training of Radiation Oncology and Medical Physics Residents and Fellows Brian Winey, PhD,* Helen A. Shih, MD,* Narayan Sahoo, PhD,y Andrew Lee, MD,y Neha Vapiwala, MD,z and Stefan Both, PhDz *Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; yUniversity of Texas, MD Anderson Cancer Center, Houston, Texas; and zUniversity of Pennsylvania, Philadelphia, Pennsylvania
Pollen Performance in Clarkia Taxa with Contrasting Mating Systems: Implications for Male Gametophytic Evolution in Selfers and Outcrossers

We tested three predictions regarding the joint evolution of pollen performance and mating system. First, due to the potential for intense intrasexual competition in outcrossing populations, we predicted that outcrossers would produce faster-growing pollen than their selfing relatives. Second, if elevated competition promotes stronger selection on traits that improve pollen performance, then, among-plant variation in pollen performance would be lower in outcrossers than in selfers. Third, given successive generations of adaptation to the same maternal genotype in selfers, we predicted that, in selfing populations (but not in outcrossing ones), pollen would perform better following self- than cross-pollinations. We tested these predictions in field populations of two pairs of Clarkia (Onagraceae) sister taxa. Consistent with our predictions, one outcrosser (C. unguiculata) exhibited faster pollen germination and less variation in pollen tube growth rate (PTGR) among pollen donors than its selfing sister species, C. exilis. Contrary to our predictions, the selfing C. xantiana ssp. parviflora exhibited faster PTGR than the outcrossing ssp. xantiana, and these taxa showed similar levels of variation in this trait. Pollen performance following self- vs. cross-pollinations did not differ within either selfing or outcrossing taxa. While these findings suggest that mating system and pollen performance may jointly evolve in Clarkia, other factors clearly contribute to pollen performance in natural populations.