cssi/SciSciGPT-SciSciNet huggingface dataset:
Histone H3.3 maintains genome integrity during mammalian development

Histone H3.3 is a highly conserved histone H3 replacement variant in metazoans and has been implicated in many important biological processes, including cell differentiation and reprogramming. Germline and somatic mutations in H3.3 genomic incorporation pathway components or in H3.3 encoding genes have been associated with human congenital diseases and cancers, respectively. However, the role of H3.3 in mammalian development remains unclear. To address this question, we generated H3.3-null mouse models through classical genetic approaches. We found that H3.3 plays an essential role in mouse development. Complete depletion of H3.3 leads to developmental retardation and early embryonic lethality. At the cellular level, H3.3 loss triggers cell cycle suppression and cell death. Surprisingly, H3.3 depletion does not dramatically disrupt gene regulation in the developing embryo. Instead, H3.3 depletion causes dysfunction of heterochromatin structures at telomeres, centromeres, and pericentromeric regions of chromosomes, leading to mitotic defects. The resulting karyotypical abnormalities and DNA damage lead to p53 pathway activation. In summary, our results reveal that an important function of H3.3 is to support chromosomal heterochromatic structures, thus maintaining genome integrity during mammalian development.
Rapid and specific assay of collagen glucosyltransferase with a Sepharose-bound substrate

Abstract A simple and specific assay has been developed for collagen glucosyltransferase in which a solid-phase substrate, consisting of a mixture of Type II collagen peptides linked to CNBr-activated Sepharose 4B, is used. Following incubation with enzyme, the substrate is simply washed, and its radioactivity is determined. The specificity of the procedure has been validated by the isolation of radiolabeled Glc-Gal-Hyl from the reaction products after incubation with a crude enzyme preparation from embryonic chick cartilage. Under the conditions described, product formation was linear for 6 h and was proportional to the concentration of enzyme protein up to 180 μg/ml. The Km was 33 μ m for UDP-glucose and 48 μ m for the gel-bound collagen substrate, expressed as Gal-Hyl. The Vmax for the Sepharose-bound substrate was 30% of the value observed for the identical substrate in soluble form, suggesting that the solid matrix exerted some sterical hindrance on the bound substrate.
Diversity in hydrogen evolution from bidirectional hydrogenases in cyanobacteria from terrestrial, freshwater and marine intertidal environments

We characterized a set of 36 strains of cyanobacteria isolated from terrestrial, freshwater and marine intertidal settings to probe their potential to produce hydrogen from excess reductant, in the hope of finding novel strains with improved traits for biohydrogen production. The set was diverse with respect to origin, morphology, taxonomy and phylogeny. We found that about one half of the strains could produce hydrogen from hydrogenases in standard assays, a trait that corresponded invariably with the presence of homologues of the gene hoxH, coding for subunit H in the bidirectional Ni-Fe hydrogenase. Strains from freshwater and intertidal settings had a high incidence of hydrogen producing, hoxH containing strains, but all terrestrial isolates were negative for both. While specific rates of hydrogen production varied among strains, some novel strains displayed rates several fold higher than those previously reported. We detected two different patterns in hydrogen production. Pattern 1, corresponding to that previously known in Synechocystis PCC 6803, encompassed strains whose hydrogenase system produced hydrogen only temporarily to revert to hydrogen consumption within a short time and after reaching moderate hydrogen concentrations. Cyanobacteria displaying pattern 2, in the genera Lyngbya and Microcoleus, tended to have higher rates, did not reverse the direction of the reaction and reached much higher concentrations of hydrogen at steady state, making them of interest as potential platforms for biohydrogen production.
Prepurchase Information Seeking for New Cars and Major Household Appliances

National survey data on the amount of information seeking by buyers of new cars and major household appliances are analyzed by AID and MCA. The findings lend support to the hypothesis that purchase...
Inefficiency and correlation

SUMMARY Various extremal results have been proved concerning the efficiency of least squares estimates relative to Gauss-Markov estimates and concerning the canonical correlations between two sets of random variables. In this paper we show how these two types of result are related, and derive a new result from which many previous inequalities can be derived. Some key word8: Canonical correlation; Inefficiency; Least squares. The inequality for the generalized efficiency of least squares estimates relative to best linear unbiased estimates (Bloomfield & Watson, 1975; Knott, 1975) has found applications in other areas. A consequence was used by Venables (1976) in testing for sphericity of a Gaussian distribution, and by Khatri (1978) in proving extremal results for canonical correlations. We shall prove a slightly more general result concerning canonical
Cross-Cultural Comparison of Status Effects on Group Decision Making

The purpose of this study was a comparison of influence of formal status on group decision making for two cultures, the United States and India. Two identical experiments were conducted on American and Indian subjects. In both samples 36 male and female students, 12 graduate MBA and 24 freshmen or sophomores were randomly assigned to 12 groups of three in such a way that each group comprised of one graduate and two undergraduate members. Graduate students and undergraduates respectively represented high and low “specific” statuses, while male and female students respectively represented high and low “diffuse” statuses. Prior to group discussions, the participants introduced themselves to the group by stating, among other things, their academic status. Two standard “choice-dilemma” problems were discussed by each group with the order of the problems randomly counterbalanced. The experimental procedure followed the “risky shift” paradigm. Analysis of variance revealed that educational status had significant...
A creative and low‐cost method of teaching hands‐on engineering experimentation using virtual instrumentation

Virtual instrumentation is now used in the college level to teach mechanical engineering experimentation to undergraduates at Tufts University. By combining LabVIEW® with LEGO® Dacta blocks, students learn to write virtual instrumentation programs to interact with external sensors and actuators in an innovative hands-on approach to engineering experiments. The LEGO Data Acquisition and Prototyping System (LDAPS) is a collection of versatile LEGO sensors, motors, building blocks, and a computer I/O interface as well as LabVIEW Student Edition. It provides a highly capable, infinitely versatile, and expandable system for data acquisition and experimentation. The system is inexpensive (under $500 for a complete workstation without the computer), and because of the nature of LEGO blocks, it is fun, easy to use, and inspires creativity in students. By combining the LDAPS tools with the LabVIEW graphical programming language, students can create their own virtual instruments to acquire and analyze data with LEGO sensors, perform advanced signal-processing techniques, or program LEGO vehicles for interactive control. This article presents the method by which students are taught engineering experimentation and virtual instrumentation as well as describes the college-level course where it is used and a brief outline of how the same concepts are taught to students in other classes and in grades K–12. © 1998 National Instruments. Published by John Wiley & Sons, Inc. Lab Robotics and Automation 10: 63–66, 1998
Nosema ceranae in age cohorts of the western honey bee (Apis mellifera).

Abstract Nosema ceranae intensity (mean spores per bee) and prevalence (proportion of bees infected in a sample) were analyzed in honey bees of known ages. Sealed brood combs from five colonies were removed, emerging bees were marked with paint, released back into their colonies of origin, and collected as recently emerged (0–3 days old), as house bees (8–11 days old), and as foragers (22–25 days old). Fifty bees from each of the five colonies were processed individually at each collection date for the intensity and prevalence of N. ceranae infection. Using PCR and specific primers to differentiate Nosema species, N. ceranae was found to be the only species present during the experiment. At each collection age (recent emergence, house, forager) an additional sample from the inner hive cover (background bees = BG) of each colony was collected to compare the N. ceranae results of this sampling method, commonly used for Nosema spore quantification, to the samples comprised of marked bees of known ages. No recently emerged bees exhibited infection with N. ceranae. One house bee out of the 250 individuals analyzed (prevalence = 0.4%) tested positive for N. ceranae, at an infection level of 3.35 × 106 spores. Infection levels were not statistically different between the recently emerged (mean = 0 spores/bee) and house bees (mean = 1.34 × 104 spores/bee) (P = 0.99). Foragers exhibited the highest prevalence (8.3%) and infection intensity (mean = 2.38 × 106 spores/bee), with a range of 0–8.72 × 107 spores in individual bees. The average infection level across all foragers was significantly higher than that of recently emerged bees (P = 0.01) and house bees (P = 0.01). Finally, the prevalence of Nosema in infected bees was found to be positively correlated with the infection intensity in the sample.
A Moderate-Power Nitrogen Microwave-Induced Plasma as an Alternative Ion Source for Mass Spectrometry

The moderate-power nitrogen plasma is evaluated as an alternative ion source for plasma mass spectrometry. The nitrogen MIP-MS exhibits linear dynamic ranges of about 3-4 orders of magnitude and low ppb to sub-ppb detection limits for most elements under multielement scanning conditions. Nitrogen MIP-MS is capable of determining K, Ca, Cr, As, and Se at their major isotopes. In addition, nitrogen MIP-MS provides lower detection limits than argon ICP-MS for K (0.48 ppb) and Ca (0.24 ppb). The nitrogen MIP-MS system allows the determination of isotope ratios for 10 ppm of Ca (40/44) and 100 ppb of K (39/41), Cr (52/53), and Se (80/78) with less than 5% error.
Contraction of Isolated Human Breast Cutaneous Vascular Smooth Muscle

In isolated vascular strips from normal human breast skin, the threshold for contractile response was 2 × 10 −11 gm/ml for norepinephrine and 6 × 10 −11 gm/ml for epinephrine. Isoproterenol gave contractile responses at 1 × 10 −6 gm/mI. Blockade with phentolamine and propranolol indicated alpha receptor activity. Serotonin and angiotensin also induced contractile responses. Physiologic and pharmacologic dosages of' histamine, bradykinin, acetyicholine, and methacholine did not cause any significant response. Contractile response occurred with adenosine diphosphate and adenosine triphosphate but not with cyclic adenosine 3',5'-monophosphate. Phasic activity occurred in most vessels when stimulated by catecholamine and in all vessels when the concentration of potassium chloride in the bath was increased. Species differences are indicated because skin vessel strips from humans respond only to serotonin, while those from dogs respond to serotonin and bradykinin and those from rabbits respond to serotonin and histamine.
Developmental regulation of mitochondrial biogenesis in Trypanosoma brucei.

The metabolism ofTrypanosoma brucei undergoes a significant change as the parasite differentiates from the mammalian bloodstream form to the form found in the tse-tse fly vector. Because the mitochondria of bloodstream form cells lack cytochromes and several key citric acid cycle enzymes, the metabolism of these cells is mostly limited to glycolysis. The reducing equivalents generated by this process are passed to oxygen by a plantlike alternative oxidase. As cells differentiate to the insect form, they begin to oxidatively metabolize proline. The mitochondria of insect form cells contain functional, cytochromemediated electron transport chains and have complete complements of citric acid cycle enzymes. Although the characterization is far from complete, the nuclear and mitochondrial genes involved in the expression of these mitochondrial functions appear to be developmentally regulated at posttranscriptional and posttranslational levels. This review outlines some of the molecular processes that are associated with the developmental regulation of mitochondrial biogenesis and suggests some possible mechanisms of regulation.
Mexico's drug networks: Modeling the smuggling routes towards the United States

Abstract Drug smuggling routes are chosen to maximize profit while minimizing costs. Routes with the least drug transportation costs and the lowest risk for drug confiscation and gang fight are most preferred. This study attempts to predict the ground trafficking corridors for transporting marijuana and opium derivatives from Mexico to the United States border. The cost surface, representing impedance to transport illicit drugs, is modeled by considering physical, socio-demographic, and drug violence factors. The impedance is then transferred to the road network to represent the cost for moving drugs along the roads, which becomes the main input for network analysis. The results from the routes simulation confirm largely the known territory divisions and the drug trafficking routes of the major Mexican drug organizations. The findings help us understand the development of drug trafficking routes in Mexico, which can potentially enhance our capability to predict the dynamics of drug smuggling routes.
Lifetime of the 724.3-keV level and shell-model intruder states in Ag 109

The half-life of the ${\frac{3}{2}}^{+}$, 724.3-keV level in $^{109}\mathrm{Ag}$, populated in the decay of $^{109}\mathrm{Pd}$, has been determined to be 3.2\ifmmode\pm\else\textpm\fi{}0.8 nsec. The observed lifetime and $\ensuremath{\gamma}$-ray branching supports the interpretation that the rotational band structure in the odd-mass Ag isotopes arises from the ${g}_{\frac{7}{2}}$ shell-model state.
Characteristics of a kilometer-scale high strain zone in the lower continental crust: Mt. Hay block, central Australia

Abstract A granulite facies high strain zone was studied on Capricorn Ridge, part of the Mt. Hay block granulites in the Arunta inlier, central Australia. Deformation occurred in these primarily mafic composition granulites at lower crustal conditions (∼8 kb, ∼800 °C) at 1740–1690 Ma. Pervasive and consistently oriented foliation (striking SSW and dipping steeply) and lineations (pitching steeply eastward) occur within the shear zone. The high strain zone is recognized by the presence of SL-tectonites, parallelism of grain shape fabrics and lithologic boundaries, transposition of lithologic boundaries into parallelism with the foliation, and the local occurrence of sheath-like folds. Field-based fabric mapping uses compositional foliation intensity as a proxy for finite strain to document strain variations within the Capricorn Ridge high strain zone. There is no observed microstructural grain size reduction that corresponds to these strain variations. Fabric intensity increases from the centers of the major lithologic units towards the contacts. 100 m-scale strain localization within Capricorn ridge occurs adjacent to major lithologic contacts, indicating competency contrast during lower crustal deformation.
Experimental Etiocholanolone Fever

Thirty-five patients were injected with etiocholanolone intramuscularly and 27 responded with fever greater than 1.5 F and leukocytosis. The clearance and conjugation of etiocholanolone were studied after intramuscular and intravenous injection. The peak level of free or conjugated steroid did not correlate with the febrile spike produced. The local reaction at the site of the injection and the leukocytosis were directly related to the magnitude and duration of fever. Three of 4 leukopenic patients failed to get either a local reaction or generalized fever. However, the failure of the leukopenic patients to react with fever may have been related to their underlying disease process. The data suggest that a local inflammatory reaction may be significant etiologically in the production of etiocholanolone fever.
Basic Self-Knowledge: Answering Peacocke’s Criticisms of Constitutivism

Constitutivist accounts of self-knowledge argue that a noncontingent, conceptual relation holds between our first-order mental states and our introspective awareness of them. I explicate a constitutivist account of our knowledge of our own beliefs and defend it against criticisms recently raised by Christopher Peacocke. According to Peacocke, constitutivism says that our second-order introspective beliefs are groundless. I show that Peacocke’s arguments apply to reliabilism not to constitutivism per se, and that by adopting a functionalist account of direct accessibility a constitutivist can avoid reliabilism. I then argue that the resulting view is preferable to Peacocke’s own account of self-knowledge.
A spectrophotometric assay for conjugation of ubiquitin and ubiquitin-like proteins

Ubiquitination is a widely-studied regulatory modification involved in protein degradation, DNA damage repair and the immune response. Conjugation of ubiquitin to a substrate lysine occurs in an enzymatic cascade involving an E1 ubiquitin activating enzyme, and E2 ubiquitin conjugating enzyme, and an E3 ubiquitin ligase. Assays for ubiquitin conjugation include electrophoretic mobility shift assays and detection of epitope-tagged or radiolabeled ubiquitin, which are difficult to quantitate accurately and are not amenable to high throughput screening. We have developed a colorimetric assay that quantifies ubiquitin conjugation by monitoring pyrophosphate released in the first enzymatic step in ubiquitin transfer, the ATP-dependent charging of the E1 enzyme. The assay is rapid, does not rely on radioactive labeling, and requires only a spectrophotometer for detection of pyrophosphate formation. We show that pyrophosphate production by E1 is dependent on ubiquitin transfer and describe how to optimize assay conditions to measure E1, E2, or E3 activity. The kinetics of polyubiquitin chain formation by Ubc13-Mms2 measured by this assay are similar to those determined by gel assays, indicating that the data produced by this method are comparable to methods that measure ubiquitin transfer directly. This assay is adaptable to high-throughput screening of ubiquitin and ubiquitin-like conjugating enzymes.
Steroid influences upon discharge frequencies of intact and isolated pacemakers of weakly electric fish

The effects of gonadal steroids upon the discharge frequencies of the weakly electric fishApteronotus rostratus were examined. Androgens elicited frequency decreases, while estrogens had no effect. The androgen-induced decreases occurred with very short latencies and lasted only for several hours. The medullary nucleus that controls the discharge frequencies of these animals was subsequently isolated in an in vitro preparation. The effects of steroids were tested on the isolated pacemaker, and were found to be similar to those seen in intact animals. Thus, steroid effects upon discharge frequencies appear to be a consequence of direct effects upon the pacemaker. The short time course of the response suggests non-genomic effects of steroids upon neuronal activity in the pacemaker.
High compression of SAR imagery for battlefield surveillance

In this paper a compression algorithm is developed to compress SAR imagery at very low bit rate. A new vector quantization (VQ) technique called the predictive residual vector quantizer (PRVQ) is presented for encoding the SAR imagery. Also a variable-rate VQ scheme called the entropy- constrained PRVQ (EC-PRVQ), which is designed by imposing a constraint on the output entropy of the PRVQ, is designed. Experimental results are presented for both PRVQ and EC-PRVQ at high compression ratios. The encoded images are also compared with that of a wavelet-based coder.
Pharmacological evidence for involvement of the sympathetic nervous system in the increase in renin secretion produced by a low sodium diet in rats.

Abstract To determine the degree to which increased sympathetic activity contributes to the increase in renin secretion produced by a low sodium diet, the β-adrenergic blocking drug propranolol or saline vehicle was injected through indwelling jugular cannulas in rats fed a normal diet and rats fed a low sodium diet for 9 days. Plasma renin activity (PRA) and plasma renin concentration (PRC) were elevated by the low sodium diet, and these values were reduced 42–45% by propranolol, although they were still higher than in the normal diet controls. Plasma corticosterone was moderately elevated in cannulated rats on regular diet, compared to decapitated controls, but corticosterone did not differ between cannulated and decapitated rats on low salt diet; propranolol reduced plasma corticosterone. However, PRA and PRC were comparable in cannulated rats and decapitated controls on both the normal and the low sodium diets, and propranolol did not produce a significant reduction in PRA and PRC in rats fed the normal diet. This indicates that the effects of propranolol on PRA and PRC in the low sodium rats were not simply due to reduction of a stress-induced increase in renin secretion. The results indicate that increased sympathetic activity makes a substantial contribution to the increase in renin secretion produced by 9 days of dietary sodium restriction.
Oceanographic observations of the 1982 warming of the tropical eastern pacific.

Moored current meter, sea level, hydrographic, and surface drifter measurements show the large changes that took place in the eastern tropical Pacific during the onset of the warm episode of 1982. In August the near-surface flow at 0 degrees , 110 degrees W reversed direction to eastward. By October the sea surface temperature in the equatorial zone increased by 5 degrees Celsius above the long-term monthly mean value, sea level rose by 22 centimeters at the Galapagos Islands, and the thermocline was displaced downward by 50 to 70 meters along the equator and the South American coast.
Stress testing a supply chain using simulation

Simulation provides the capability to evaluate performance of a system operating under current or proposed configurations, policies and procedures. It is very applicable to evaluation of strategic and operational level plans for supply chains. It is especially useful for exploring the viability of a supply chain before beginning production. This paper describes the use of simulation for determining the readiness of a supply chain designed by a small company for providing sub-systems to a defense contractor. The supply chain had to be stress tested at surge and mobilization volume levels to meet the requirements. Simulation provided the ideal methodology to identify and demonstrate the behavior of the supply chain under stress and evaluate strategies to meet the defined volumes. It was used to prove the readiness of the supply chain reducing perceived risks in using the virtual operation.
Methionine Sulfoxide Reductase in Helicobacter pylori: Interaction with Methionine-Rich Proteins and Stress-Induced Expression

The reductive repair of oxidized methionine residues performed by methionine sulfoxide reductase is important for the gastric pathogen Helicobacter pylori to maintain persistent stomach colonization. Methionine-containing proteins that are targeted for repair by Msr were identified from whole-cell extracts (after cells were exposed to O2 stress) by using a coimmunoprecipitation approach. Proteins identified as Msr-interacting included catalase, GroEL, thioredoxin-1 (Trx1), and site-specific recombinase; with one exception (Trx1, the reductant for Msr) all these proteins have approximately twofold higher methionine (Met) content than other proteins. These Met-rich proteins were purified and were shown to individually form a cross-linked adduct with Msr. Catalase-specific activity in an msr strain was one-half that of the parent strain; this difference was only observed under oxidative stress conditions, and the activity was restored to nearly wild-type levels by adding Msr plus dithiothreitol to msr strain extracts. In agreement with the cross-linking study, pure Msr used Trx1 but not Trx2 as a reductant. Comparative structure modeling classified the H. pylori Msr in class II within the MsrB family, like the Neisseria enzymes. Pure H. pylori enzyme reduced only the R isomer of methyl p-tolyl-sulfoxide with an apparent Km of 4.1 mM for the substrate. Stress conditions (peroxide, peroxynitrite, and iron starvation) all caused approximately 3- to 3.5-fold transcriptional up-regulation of msr. Neither the O2 level during growth nor the use of background regulatory mutants had a significant effect on msr transcription. Late log and stationary phase cultures had the highest Msr protein levels and specific activity.
Deposition and remobilization of graphene oxide within saturated sand packs

Abstract In this research, we examined the deposition kinetics of graphene oxide (GO) particles within saturated sand packs as a function of ionic strength as well as the remobilization of previously retained GO particles due to chemical perturbation. The retention of GO particles within saturated quartz sand was found to be strongly dependent on ionic strength. At low ionic strength (e.g., 1 mM of NaCl), little retention of GO particles occurred. When the ionic strength was increased to 100 mM of NaCl, the retention of GO particles increased significantly but would be limited by its retention capacity. The reduction of ionic strength from 100 mM (NaCl) to 1 mM (NaCl) released ∼100% of previously retained GO particles. The transport behavior of GO particles within saturated sand packs could be described by the Langmuir-type of transport model. The extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) theory, which considers Lifshitz–van der Waals (LW) interaction, the electrostatic double layer (EDL) interaction as well as the Lewis acid–base (AB) (i.e., hydrophobic) interaction between GO plates and the surface of quartz sand, could explain the observed trend of GO retention under various ionic strength conditions.
Promotion of ulcerative duodenitis in young ferrets by oral immunization with Helicobacter mustelae and muramyl dipeptide.

Background. The purpose of this study was to determine whether oral immunization of ferret kits with a whole-cell sonicate of Helicobacter mustelae lysate (Hml) and the adjuvant muramyl dipeptide (MDP) would reduce the incidence of natural colonization with H. mustelae and the extent of Helicobacter-associated gastritis by enhancing the host mucosal immune response. Materials and Methods. Between the ages of 4 and 11 weeks, 44 ferret kits were gavaged with Hml and various doses of MDP. The extent of gastritis and duodenitis and the immune response to H. mustelae were evaluated. Results. All kits became colonized naturally with H. mustelae and the majority developed mild to severe gastritis and duodenitis. Kits that received Hml with MDP developed significantly greater inflammation of the gastric antrum and duodenum, as compared to kits vaccinated with Hml alone. Vaccination with Hml and 50 μg of MDP was associated with severe lesions in the proximal duodenum characterized by accumulation of mononuclear inflammatory cells, mucosal erosion, and ulceration. Although serum antibody specific for H. mustelae in 4-week-old kits was approximately 50% of adult levels, a finding attributable to passively acquired maternal antibody, both systemic and mucosal antibody levels became depressed over time despite oral vaccination. The humoral immune response was sufficiently low to prevent detection of any significant dose effect of MDP on antibody levels among experimental groups. Conclusions. Oral vaccination of young ferrets with Hml and 50 μg MDP increased the risk of Helicobacter-associated mucosal ulceration in the proximal duodenum, which was associated with low humoral (but significant cell-mediated) immune responses to H. mustelae. In retrospect, the frequency of vaccination may have suppressed the systemic humoral immune response, thereby promoting mucosal damage by H. mustelae. The 50-μg dose of MDP enhanced the cell-mediated immune response, which indirectly contributed to development of severe lesions. The increased frequency of mucosal damage associated with this vaccination regimen enhances the value of the ferret model for studying duodenal ulceration secondary to Helicobacter infection.
Optical delay with a line-by-line resolution pulse shaper

We demonstrate an optical delay line using a virtually imaged phased-array (VIPA) pulse shaper, producing time delays in discrete steps of 40 ps over the full repetition period of the laser.
Flux pinning and forced entanglement by splayed columnar defects

Abstract We propose controlled splay of artificial columnar defects in cuprate superconductors as a strategy to enhance trasport properties in field compared to parallel columns. The theory predicts a new “splayed glass” phase with a greatly reduced flux creep, an intangled ground state, and very slow response to a transverse field.
Task difficulty and visual similarity increase a distractor's effects on random shapes.

Summary.-Recognition of random shapes followed by a visual distractor is altered by the type of distractor and whether the distractor needs to be attended. Three experiments tested which characteristics modify a visual distractor's effect on random target shapes presented for 75 to 150 msec. Exp. I showed that increasing the number of digits to be remembered (1, 3, or 8) increased the effectiveness of digits as distractors. Exp. 2 indicates that all novel visual stimuli are nor equivalent in their effect as visual distractors for random target shapes. Random shapes were highly effective as distractors, while pictures of faces or complex colored pictures had a relatively small effecr. In Exp. 3 decreasing che presentation time for novel visual distractors decreased recognition of the distractors but not of random target shapes. However, adding a three-digit distractor after the novel visual distractor did decrease recognition of target shapes. Exps. 2 and 3 showed thar the order of the recognition tests of the target and distracting stimuli altered target recognition if and only if subjects did know which was to be reported first. These experiments indicate chat the effect of a visual distractor depends on both. the extent to which it is allotted attention and its visual similarity to the target stimulus. Recent studies have demonstrated three stages in recognition memory for novel visual stimuli, each of which is characterized by a differential susceptibility to disuaction by additional visual stimuli. In the first stage, referred to as brief visual or iconic storage, the stimulus is degraded by any immediately subsequent visual (masking) stimulus. A visual mask has a consistently measurable effect if presented within 150 msec. of the stimulus onset for random shapes (Hines & Smith, 1977) and for complex pictures (Potter, 1976; Hulme & Merikle, 1976), and some masking effects may occur for up to 500 msec. (Loftus & Bell, 1976). Stimuli in the second memory stage may also be degraded by a subsequent stimulus. However, in contrast to the first stage the degree of interference depends on both the type of distracting stimulus and whether it needs to be attended. Hines and Smith (1977) found that unattended shapes, digits, or Iine-grid distractors had no effect on recognition of random target shapes after a total processing time, that is, the stimulus presentation time plus the uninterrupted poststimulus interval, of 150 to 300 msec. Attended shape disuactors, however, severely disrupted the recognition of the target shapes, and attended digit distractors had a moderate distracting effect. Nonvisual distractors can also disrupt the recognition of visual target stimuli during this stage; Kelley
Varicella-Zoster Virus ORF57, Unlike Its Pseudorabies Virus UL3.5 Homolog, Is Dispensable for Viral Replication in Cell Culture

Varicella zoster virus (VZV) encodes five genes that do not have homologs in herpes simplex virus. One of these genes, VZV ORF57, is predicted to encode a protein containing 71 amino acids. Antibody to ORF57 protein immunoprecipitated a 6-kDa protein in the cytosol of VZV-infected cells. Although the homolog of VZV ORF57 in pseudorabies virus, UL3.5, is critical for viral egress and growth in cell culture, VZV unable to express ORF57 replicated to titers similar to those seen with parental virus. Thus VZV ORF57 has a different role in viral replication than its pseudorabies virus homolog.
Incorporation of [2,3-13C]succinate into methyl-branched alkanes in a termite

Abstract Carbon-13 nuclear magnetic resonance was used to examine the incorporation of [2,3-13C]succinate into methylalkanes in the termite Zootermopsis angusticollis. Carbons 2 and 3 of succinate were preferentially incorporated into the branching methyl group(s) and the tertiary carbon(s) of monomethyl- and dimethylalkanes. These data support a pathway in which succinate is metabolized to methylmalonyl-coenzyme A, and is then incorporated in place of malonyl-coenzyme A at specific points during chain elongation.
Endogenous hyperthermia in normal human subjects: I. Experimental study of evoked potentials and reaction time

Previous work on awake guinea pigs and rats in the authors’ laboratory revealed that microwave-induced elevations of brain temperature (ΔTs from 1° to 3° C over resting baselines) are associated with reliable reductions in latencies of flash-evoked brain potentials’ (EPs). To assess the generality of this finding in the normal human being, and to avoid the ethical problem of whole-body human exposure to an intense microwave field, ΔTs were induced endogenously by vigorous exercise and by insulative and vapor-barrier clothing. Twenty male athletes, 18 to 22 years of age, were randomly but equally divided into counterbalanced experimental and control groups for a single 3-h morning or afternoon session of measurements. During baseline measures, EPs of three types were observed: flash-evoked N1, pattern-reversal P100, and event-related P300. In addition, simple reaction times (RTs) to photic stimulation were recorded. All measures were repeated after sham warming of the 10 control subjects and after tympanically indexed brain temperatures of the 10 experimental subjects were elevated by an average of 1.2° C above control values. EP and RT latencies were reliably reduced in association with the ΔTs, the mean reductions ranging from 3% to 9%. The data on the human flash-evoked N1 component compare favorably with data recorded from rats and guinea pigs that have undergone exogenous elevations of temperature by microwave irradiation. The data on RTs and other EP components are consistent with the thesis that human CNS activity in general is accelerated during a modest bout of whole-body hyperthermia.
Decay of 194Os

Abstract The 194 Os nucleus, produced by successive n, γ reactions on 192 Os, has been found to decay with a half-life of 6.0±0.2 y. The gamma-ray spectrum showed a prominent transition at 43.0±0.4 keV, a very weak one at 78±3 keV and the characteristic K and L X-rays of iridium. No gamma-gamma coincidences were detected. A single beta-ray group at 53±4 keV was observed in the single-crystal (anthracene) measurements and in coincidence with the 43 keV gamma ray. A weak 17 keV beta-ray branch of 2% is deduced from the gamma-ray data and an upper limit of 5% is set for any beta-ray branch going to the 194 Ir ground state. Two excited states in 194 Ir were found corresponding in energies to the gamma-ray transitions. The 43 keV state is depopulated by M1 radiation and the 78 keV state by a mixture of M1 and E2 with E 2 M 1 = 1.1
On the synthesis of a class of 2-D acausal lossless digital filters

Passive and lossless two-dimensional (2-D) discrete systems of the fully recursive half-plane type are reviewed as one-dimensional (1-D) filters over convolutional algebra. Necessary and sufficient conditions for 2-D transfer functions to be valid scattering as well as immittance description of such systems are obtained. An algorithm for the structurally passive (in fact, lossless) synthesis of filters having such recursive structure is then derived from these representation results as an extension of a recent 1-D Schur-type algorithm for the synthesis of discrete lossless two-ports. Comments on various aspects of design and implementation of such 2-D filters potentially useful in practical problems are also made. >
Cranial suture simulator for ultrasound diagnosis of craniosynostosis.

Background: In evaluating the effectiveness of ultrasound as a screening tool for craniosynostosis it was discovered that sonologists and sonographers needed more experience scanning and visualizing cranial sutures on ultrasound. Objective: To create an ultrasound simulator to train radiologists and technologists to locate and recognize patent and fused cranial sutures in children. Materials and methods: The hypoechoic appearance of patent sutures was simulated by cutting lines into life-sized plastic doll heads and filling them with a commercial hypoechogenic material. Fused hyperechoic sutures were simulated by not cutting into the hard plastic region of a suture. The simulator’s teaching value was evaluated on three radiology residents and three fellows. Subjects performed pre-training scans on unknown simulators, received feedback and an opportunity to scan a training simulator, and then performed post-training scans on random unknown simulators. Accuracy was recorded as percentage of correctly demonstrated sutures. Results: The suture simulator reproduces the sonographic appearance of patent and fused cranial sutures. Accuracy of acquisition, interpretation, and overall diagnosis increased from 64 to 91%, 79 to 91%, 61 to 97%, respectively, between pre and post training scans. Conclusion: An ultrasound simulator can reproduce the appearance of patent and fused cranial sutures in children and can be used to train radiologists and technologists in the performance of a screening protocol.
Anti-Optimization Versus Probability in an Applied Mechanics Problem: Vector Uncertainty

In this study probabilistic and nonprobabilistic anti-optimization approaches are contrasted to evaluate their relative advantages and disadvantages while solving a mechanical problem in presence of vector uncertainty. The different cases that are analyzed in probabilistic setting that deal with either uniform or generic probability density functions for the uncertain variables varying in a rectangular domain. This case has been compared with interval analysis, a particular case of anti-optimization. The presence of a convex, smooth boundary of the uncertain domain has been also considered for comparing results obtained with these two alternative methods. It is shown that in case of vector uncertainty the anti-optimization method yields the same solution for the design problem as is provided by means of more complex probabilistic considerations.
The caldesmon content of vertebrate smooth muscle

Abstract Caldesmon and tropomyosin can be selectively and quantitatively extracted from vascular and visceral smooth muscle following heat treatment; all other smooth muscle proteins are precipitated by this procedure. Estimates of the caldesmon/tropomyosin molar ratio in heat-extracts determined by SDS-PAGE densitometry are 1 caldesmon:5.1–5.3 tropomyosin for rabbit and sheep aorta, and 1 caldesmon:5.9 tropomyosin for rabbit stomach and chicken gizzard. If the assumption is made that tropomyosin serves as a true reference of thin-filament content in intact muscle, it follows that the relative caldesmon contents in the above tissues are similar to each other. Caldesmon in heat extracts was identified by Western blotting, by its anomalous migration on several different SDS-PAGE systems and by its position on two-dimensional PAGE. Values of caldesmon contents in unfractionated total tissue homogenates were found to be similar to those cited above. Smooth muscles contain different thin-filament classes and only one type appears to possess caldesmon. By comparing values for the molar composition of caldesmon-specific filaments (1 caldesmon:2 tropomyosin:14 actin) with the values above determined for intact tissue, we conclude that the caldesmon filaments account for approx. 34–45% of he total thin-filament pool in arterial smooth muscle and slightly less in visceral muscles.
Retinal Microvascular Surgery: A Feasibility Study

PURPOSE. To evaluate the feasibility of microvascular surgery at the level of the retinal vasculature. METHOD. Porcine eyes were used, and eyecups were prepared under an operating microscope. Several classic microvascular maneuvers were explored, such as vascular puncturing, catheterization, mobilization, intravascular injections, and various combinations of the same. Instruments used ranged from disposable 30-gauge needles to an Er:YAG laser. Commercially available 10-0 nylon sutures, fine polyimide tubes, and custom-made fine glass tubes were used for vascular catheterization. RESULTS. Puncturing, mobilization, catheterization, and intravascular injection of retinal arteries and veins were possible. The connection of two remote retinal vessels with a fine tube was also achieved with the combination of these maneuvers. CONCLUSIONS. The feasibility of performing several microvascular maneuvers on retinal arteries and veins was demonstrated in porcine eyes. Further experimentation and development of these findings in a living animal model could lead to the development of such microvascular maneuvers in humans.
Supplementary Analysis of Io's Disk-Integrated Solar Phase Curve

Abstract Analysis of the disk-integrated phase curves of Io's leading and trailing hemispheres, as derived from combined groundbased and Voyager spacecraft measurements, shows that Io's leading side is more porous than its trailing hemisphere (assuming a globally uniform particle grain size distribution) and that the material of the trailing side is more opaque at 0.47 and 0.55 μm than the material of the leading hemisphere. The scattering nature of the leading hemisphere particles in the optically active layer of the regolith demonstrates both forward and backward scattering components. At 0.47 μm the forward scattering component is larger in amplitude than the backward scattering component, whereas at 0.55 μm they are nearly equivalent. No large phase angle data was available to adequately constrain the scattering behavior of the trailing hemisphere regolith. Measures of the geometric albedo are higher for the leading hemisphere than for the trailing hemisphere. Leading hemisphere geometric albedos are ∼0.7 to ∼0.85 at 0.47 and 0.55 μm, respectively. Trailing hemisphere albedos are ∼0.64 to ∼0.82 at 0.47 and 0.55 μm, respectively. Phase integral values for the leading hemisphere are 0.61 and 0.59 at 0.47 and 0.55 μm, respectively, which are lower than previously quoted values. Measures of the phase coefficient are higher than those previously published in the literature. No variations in Hapke parameter derived surface characteristics are observed between jovian and anti-jovian hemispheres.
Effect of Yersinia pestis infection on temperature preference and movement of the Oriental rat flea (Xenopsylla cheopis) (Siphonaptera: Pulicidae).

Previous laboratory studies have shown that inoculation of bacterial endotoxin into the hemocoel of some arthropods, or natural infection by a number of pathogens, causes them to seek out a higher ambient temperature. This phenomenon has been called behavioral fever. Yersinia pestis is an endotoxin-producing bacterium that relies on infection of fleas for transmission. Behavioral fever in fleas might enhance the transmission of plague if infected fleas were induced to seek out a warm-bodied host after the death of an infected host. Our study indicates that in thermal gradients Y. pestis infected Oriental rat fleas (Xenopsylla cheopis) do not exhibit behavioral fever and in one experiment sought out a significantly lower temperature.
The morbidity compression debate: risks, opportunities, and policy options for women.

ABSTRACT The morbidity compression theory proposes that we can compress the period of illness and disability in old age into an ever smaller period at the end of life. Although recent research offers fresh support for the theory, its validity remains uncertain. This paper demonstrates the importance of the theory and recent research in this area for women. It critiques the chief proponent and opposing views of the theory, and suggests a heightened emphasis on public policies promoting healthy lifestyles. These policies would reduce long-term care needs, save health care dollars, and improve the experience of aging.
Visual Discrimination of Consonants

Consonant differentiation by speechreading was determined for full-face and lips-only exposures utilizing two forms of a closed-set response test. Thirty-two female college students viewed a videot...
Synthesis of merozoite proteins and glycoproteins during the schizogony of Plasmodium falciparum.

We have investigated the protein and glycoprotein content of Plasmodium falciparum merozoites by metabolically labeling cultures of schizont-stage parasites with [35S]methionine or with [3H]glucosamine followed by incubation in nonradioactive medium to allow the schizonts to mature into merozoites, infect new erythrocytes, and develop into ring-stage parasites. The ring stages were separated from schizonts by sedimentation through Percoll. Labeled proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and visualized by fluorography. Using [35S]methionine, four major proteins (p) with apparent relative molecular weights (Mr) = 202k, 136k, 82k, and 46k and two proteins of intermediate labeling (Mr = 185k and 142k) were observed in the schizont-labeled ring-stage parasites. Because corresponding proteins were also observed in the schizont stage, we conclude that they had been present in the invading merozoite. In contrast, prominent proteins which were generally labeled during the ring stage and some major schizont-stage proteins were virtually absent in the schizont-labeled ring-stage. By labeling the parasite proteins with [3H]glucosamine followed by separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, five major glycoproteins (gp) of apparent Mr = 185k, 88k, 56k, 46k, and 34k were identified. Their presence in both the schizont and the schizont-labeled ring stage demonstrated that the merozoite contains glycoproteins. Immune owl monkey serum recognized all five glycoproteins. A comparison of proteins by two-dimensional gel electrophoresis (isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis) suggested that p185 and gp185 were identical, as were p46 and gp46.
Standard apparent reduction potentials of biochemical half reactions and thermodynamic data on the species involved.

Abstract Standard apparent reduction potentials E′° of half reactions of enzyme-catalyzed reactions are useful because they provide a global view of the apparent equilibrium constants of redox reactions. A table of E′° at a specified pH shows at a glance whether a given half reaction will drive another half reaction or be driven by it. This table can be used to calculate apparent equilibrium constants. Standard Gibbs energies of formation of species in a half reaction can be used to calculate E′° values at pHs in the range 5–9 and ionic strengths in the range of 0–0.35 M. My previously published values of E′° values for 42 half reactions has been extended by 22 new E′° values in this paper. When ΔfG° and ΔfH° are both known for all the species in an enzyme-catalyzed reaction at 298.15 K, it is possible to calculate all the standard transformed thermodynamic properties of the reaction over a range of pHs, ionic strengths, and temperatures.