cssi/SciSciGPT-SciSciNet huggingface dataset:
Phorbol ester dramatically increases incidence of methotrexate-resistant mouse cells: possible mechanisms and relevance to tumor promotion.

Abstract I have tested the hypothesis that at least some of the known tumor promoters may act by facilitating gene amplification. A series of single-step selections for resistance to methotrexate, a specific inhibitor of dihydrofolate reductase (DHFR), was carried out with 3T6 cells in the presence and in the absence of a potent tumor promoter, 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Incidence of methotrexate-resistant, colony-forming 3T6 cells is increased up to 100 fold if selection is carried out in the presence of TPA. For a major portion of this new TPA effect to be observed, it is sufficient to add TPA simultaneously with methotrexate. The effect of TPA on the incidence of methotrexate resistance is detectable at less than 20 nM TPA and is maximal at about 200 nM TPA. Phorbol (a non-promoting analog of TPA), thymidine and dimethylsulfoxide each fail to produce any TPA-like effect in this system. DHFR gene copy numbers per cell in clones resistant to 100, 200 and 300 nM methotrexate are approximately 3, 10 and 16 times higher, respectively, than the DHFR gene copy number in the parental 3T6 cells. These numbers do not depend on the presence or absence of TPA during methotrexate selection.
An analysis of Ne´de´lec's method for the spatial discretization of Maxwell's equations

Abstract In 1980 Nedelec developed a family of curl- and divergence-conforming finite elements in R 3. He proposed the use of these elements to discretize the time-dependent Maxwell equations, noting that the elements have the advantage that the discrete magnetic displacement can be made exactly divergence-free. In this paper, we shall analyze a slight generalization of Nedelec's scheme and prove essentially optimal-order convergence estimates in a variety of situations. We also demonstrate that the Nedelec method can be superconvergent at certain special points and we relate the method to Yee's finite-difference scheme. A by-product of our analysis will be a convergence proof for Yee's method.
Adenylate cyclase activators and inhibitors, cyclic nucleotide analogs, and phosphatidylinositol: effects on interrenal function of coho salmon (Oncorhynchus kisutch) in vitro.

The role of cyclic AMP (cAMP) as mediator of ACTH action on interrenal steroidogenesis was evaluated in juvenile coho salmon (Oncorhynchus kisutch). Head kidneys (containing the interrenal cells) were incubated in the absence or presence of putative adenylate cyclase activators (forskolin and cholera toxin), ACTH combined with putative adenylate cyclase inhibitors (hydrolysis-resistant ATP analogs), dibutyryl cyclic (dbc) AMP, dbcGMP, or phosphatidylinositol. The cortisol content of the incubation medium was subsequently determined by radioimmunoassay. Forskolin markedly stimulated cortisol secretion by interrenal cells. Adenylate cyclase inhibitors depressed the steroidogenic response to ACTH. Dibutyryl cAMP, but not dbcGMP, enhanced steroid secretion. Thus, cAMP seems to be an important “second messenger” for ACTH action on salmon interrenal cells. In contrast to findings in mammalian adrenocortical cells, exogenous phosphatidylinositol and cholera toxin failed to stimulate corticosteroid secretion in salmon interrenal cells. However, it was unclear whether these negative findings were an artifact resulting from the use of kidney tissue fragments instead of isolated interrenal cells.
Seeking Truth in the Murky Technological World

Beasley, B., & Haney, M. (Eds.). (2013). Social media and the value of truth. Lanham, MD: Lexington Books. 114 pp., $50.00 (Hbk). We spend countless hours keeping in touch with old friends via Face...
Removal of nail penetrating the basilar artery

Nail-gun injuries have become an increasingly prevalent source of penetrating intracranial trauma. Few cases of intracranial nail-gun injuries disturbing major cerebrovascular structures have been reported, and none entailing basilar artery involvement. We report here the case of a 51-year-old male with an intracranial nail-gun injury involving penetration of the distal basilar artery. Operative removal was accomplished under direct vision using a double concentric cranioorbital zygomatic osteotomy for a trans-Sylvian approach. We highlight the principles involved in removing foreign bodies penetrating critical neurovascular structures.
Chronic exposure to the opioid antagonist naltrexone during pregnancy: maternal and offspring effects.

Abstract McLaughlin, P. J., S. W. Tobias, C. M. Lang and I. S. Zagon. Chronic exposure to the opioid antagonist naltrexone during pregnancy: Maternal and offspring effects. Physiol Behav 62(3) 501–508, 1997.—The role of endogenous opioids in pregnancy and parturition, and the influence exerted on prenatal and postnatal features of the offspring, were studied in rats. Females received daily injections of 50 mg/kg naltrexone (NTX), a dosage found to block opioids from interacting with opioid receptors for 24 h, throughout pregnancy. No effects on the length of gestation, course of pregnancy, litter size, or the viability of the mother or offspring were noted. The body weights, crown-rump lengths, and wet and dry weights of the brain, heart, kidney, liver, and skeletal muscle (triceps surae) in neonates delivered by NTX-treated rats were substantially elevated compared to newborn animals of saline-injected mothers. Offspring exposed to NTX during prenatal life were larger in body weight and length, and organ wet and dry weights on postnatal days 10 and 21. By weaning (day 21), body weights of NTX-exposed rats were 36% greater than controls, and increases were observed in the wet weights of brain (18%), heart (42%), kidney (38%), lungs (22%), liver (44%), and triceps surae (246%). These data lead us to hypothesize that native opioids are important growth-inhibiting, tonically active regulators of prenatal ontogeny, and that events occurring in prenatal life are determinants to postnatal outcome insofar as somatic development.
Field Tests with Kairomone–Baited Traps for Cucumber Beetles and Corn Rootworms in Cucurbits

Sticky traps with and without the attractant TIC (1,2,4-trimethoxybenzene, indole, and tralls-cinnamaldehyde) were evaluated in cucurbits for capture of striped cucumber beetle, Acalymma trivittaum (F.), spotted cucumber beetle, Diabrotica undecimpunctata howardi Barber, western corn rootworm, Diabrotica virgifera virgifera LeConte, and northern corn rootworm, D. barberi Smith & Lawrence, in New York and western striped cucumber beetle, Acalymma trivittatum (Mannerheim), and western spotted cucumber beetle, Diabrotica undecimpunctata undecimpunctata Mannerheim, in California. Traps with TIC lures captured more beetles than un baited traps for all species except for western spotted cucumber beetle in 1 of 2 California trials. Yellow traps captured more striped cucumber beetle and western spotted cucumber beetle than did white traps but did not increase capture of spotted cucumber beetle or western striped cucumber beetle. The response of the western corn rootworm and northern corn rootworm to TIC varied by time of day, the greatest response occurring around midday. Increases in TIC per trap resulted in increases in capture of western spotted cucumber beetle, western striped cucumber beetle, western com rootworm, and striped cucumber beetle, but not for northern corn rootworm or spotted cucumber beetle. For cucurbits with short plant canopies, traps were most effective when placed close to the ground. In pumpkins with taller canopies, traps at canopy and midcanopy height captured the most beetles. The effect of trap height varied by time of day for spotted cucumber beetle, western corn rootworm, and northern corn rootworm, and the pattern varied for the species. Sex ratio of captured beetles varied among species and time of day. Overall, western corn rootworm and northern corn rootworm were captured in greatest numbers during the middle of the day, whereas the greatest captures of striped cucumber beetle occurred between 1800 and 0600 hours EST. Significantly greater numbers of striped cucumber beetle, western corn rootworm, and northern corn rootworm were captured on the downwind side of traps. Traps replaced 2 times per day had greater captures than traps replaced 1 time per day or 1 time every 2 d.
Mechanism of Intracellular cAMP Sensor Epac2 Activation: cAMP-INDUCED CONFORMATIONAL CHANGES IDENTIFIED BY AMIDE HYDROGEN/DEUTERIUM EXCHANGE MASS SPECTROMETRY (DXMS)

Epac2, a guanine nucleotide exchange factor, regulates a wide variety of intracellular processes in response to second messenger cAMP. In this study, we have used peptide amide hydrogen/deuterium exchange mass spectrometry to probe the solution structural and conformational dynamics of full-length Epac2 in the presence and absence of cAMP. The results support a mechanism in which cAMP-induced Epac2 activation is mediated by a major hinge motion centered on the C terminus of the second cAMP binding domain. This conformational change realigns the regulatory components of Epac2 away from the catalytic core, making the later available for effector binding. Furthermore, the interface between the first and second cAMP binding domains is highly dynamic, providing an explanation of how cAMP gains access to the ligand binding sites that, in the crystal structure, are seen to be mutually occluded by the other cAMP binding domain. Moreover, cAMP also induces conformational changes at the ionic latch/hairpin structure, which is directly involved in RAP1 binding. These results suggest that in addition to relieving the steric hindrance imposed upon the catalytic lobe by the regulatory lobe, cAMP may also be an allosteric modulator directly affecting the interaction between Epac2 and RAP1. Finally, cAMP binding also induces significant conformational changes in the dishevelled/Egl/pleckstrin (DEP) domain, a conserved structural motif that, although missing from the active Epac2 crystal structure, is important for Epac subcellular targeting and in vivo functions.
Acetylenic sugar derivatives from glycals

Abstract D - lyxo -5-Hexyne-1,2,3,4-tetrol (II) was synthesized by reaction of 3,4,6-tri- O -acetyl-2-bromo- D -glucal (I) with butyllithium. Compound I was made from tri- O -acetyl- D -glucal via its dibromo adduct and treatment with triethylamine. The α- D - gluco form of the dibromo adduct is regarded as being the active participant in the dehydrobromination. D - threo -4-Pentyne-1,2,3-triol was similarly prepared from di- O -acetyl- D -xylal. II was acetylated to its tetraacetate (II-Ac), and hydrogenated to D - lyxo -1,2,3,4-hexanetetrol. II-Ac was hydrogenated to the hexanetetrol tetraacetate, which exhibited dimorphism. Ozonolysis gave tetra- O -acetyl- D -arabinonic acid and thus provides a new general method for preparing fully acetylated aldonic acids. The CCH part of II-Ac was readily hydrated to COCH 3 , thus yielding an acyclic ketose derivative; but conditions were not found for effecting oxidative coupling of the copper(I) acetylide. Saponification of II-Ac (to II) was not accompanied by further cleavage of II into acetylene and D -erythrose. Lithium aluminum hydride converts 2,3-dibromotetrahydropyran into 3-bromotetrahydropyran, and changes the dichloride of tri- O -acetyl- D -glucal to 1,5-anhydro-2-chloro-2-deoxy- D -glucitol (and -mannitol). In the reduction of tetra- O -acetyl-α- D -glucopyranosyl bromide to tri- O -acetyl- D -glucal, some samples of zinc dust gave excellent yields, whereas other samples failed completely, even in the presence of some favored promoters.
Vulnerability of Water Distribution Systems to Pathogen Intrusion: How Effective Is a Disinfectant Residual?

Can the spread of infectious disease through water distribution systems be halted by a disinfectant residual? This question is overdue for an answer. Regulatory agencies and water utilities have long been concerned about accidental intrusions of pathogens into distribution system pipelines (i.e., cross-connections) and are increasingly concerned about deliberate pathogen contamination. Here, a simulation framework is developed and used to assess the vulnerability of a water system to microbiological contamination. The risk of delivering contaminated water to consumers is quantified by a network water quality model that includes disinfectant decay and disinfection kinetics. The framework is applied to two example networks under a worst-case deliberate intrusion scenario. Results show that the risk of consumer exposure is affected by the residual maintenance strategy employed. The common regulation that demands a “detectable” disinfectant residual may not provide effective consumer protection against microb...
Refractive Index of Aqueous HCl and the Clouds of Venus

OBSERVATIONS of the intensity and polarization of scattered solar radiation from Venus, coupled with numerical solutions to the radiative transfer equation, have in recent years fairly well defined the optical properties of the clouds of Venus. By fitting calculations of the variation of intensity of scattered light with phase angle to the phase curve of Venus, Arking and Potter1 have shown that the scattering particles are highly transparent with a refractive index between 1.3 and 1.7 in the visible spectrum. Analysis of polarization observations by Coffeen2 has further narrowed the possible range of the refractive index to between 1.43 and 1.55. Most recently, comparison of the polarization observations with exact numerical solutions to the radiative transfer equation, taking both multiple scattering and polarization into account (J. E. Hansen, private communication) has shown that the refractive index of the scattering material in the Venusian clouds should be 1.450±0.015 at the wavelength λ= 5500 A. The comparison has further shown that the scatterers are spherical particles approximately 1 µm in radius. This sphericity strongly suggests that the particles are liquid.
Spurious Elevations of Vitamin B12 with Pernicious Anemia

To the Editor: Within a 3-week period, two women, 46 and 48 years of age, presented with peripheral neuropathy and associated pancytopenia with macrocytic anemia. Clinical suspicion for pernicious anemia was high, but vitamin B12 levels were 1644 pg per milliliter (1228 pmol per liter) and 1321 pg per milliliter (975 pmol per liter), respectively (reference range, 246 to 1320 pg per milliliter [181 to 974 pmol per liter]). On subsequent bone-marrow evaluation, specimens from both patients showed profound megaloblastic features. Additional findings on laboratory tests included elevated levels of homocysteine and methylmalonic acid combined with detection of intrinsic . . .
Egg transport in lizards

The reproductive tracts of several species of lizards were examined to understand the events assoclated with the transport of discharged oocytes following ovulation. At the onset of the reproductive cycle the regressed ovaries and oviducts appear as inconspicuous structures pressed against the dorsal body wall. As the reproductive cycle progresses, they undergo marked changes in position and size. The oviducts migrate ventrally and surround the growing ovarian oocytes, which move anteriorly where coelomic space is more abundant and eventually press intimately against the infundibulum. When ovulation occurs the ostium is in a remarkably strategic location for directly receiving the ovulated oocytes. The virtual isolation of the ovaries from the general coelom by the encapsulating oviducts, and the intimate association of the pre-ovulatory oocytes with the infundibular ostium do not support the current concept advocating the migration of loose ova following ovulation. An alternative explanation for the “trans-coelomic migratiion of ova” is proposed.
Competition between estradiol and estriol for end organ receptor proteins.

Abstract Evidence is presented that estriol is a potent inhibitor of estradiol binding to specific end organ receptor proteins, suggesting a more than passive role of this material in metabolic processes. The results tend to imply a regulatory function to estriol postulated previously by other investigators. The kinetics of incorporation of radioactive estradiol in the presence of varying amounts of estriol-and vice versa-indicate competitive binding. A similar binding phenomenon has also been demonstrated in a modified in vitro system. Differences in the nature of the binding of these two steroids are discussed.
18 Years of the Fontan Operation at a Single Institution: Results From 771 Consecutive Patients

Objectives The aim of this study was to evaluate Fontan peri-operative outcomes for 771 consecutive patients. Background Since the initial description by Fontan, mortality associated with the Fontan operation has declined substantially. However, postoperative effusions remain a significant challenge. Effusions are a key determinant of postoperative length-of-stay and have been shown to be associated with the development of protein-losing enteropathy and with decreased survival. Methods This study was a single-center, retrospective review of 771 patients who underwent Fontan palliation from 1992 to 2009. Results Patients were divided into 3 eras dictated by shift in clinical practice. Overall mortality was 3.5%, 1% since 1996. Importantly, age at Stage II palliation decreased from Era 1 to Era 3 (7.1 vs. 5.9 months; p = 0.0001), whereas age at Fontan increased (1.7 vs. 2.8 years; p = 0.0001). The proportion of patients with prolonged hospital stay (46.7% vs. 8.2% vs. 19.5%, p Conclusions Mortality in the modern era is rare, whereas postoperative pleural drainage remains the dominant morbidity. Elevated pulmonary artery pressure seems to be a marker of unfavorable outcome. Continued investigation is warranted to determine whether medical interventions or alterations to operative strategy can alter peri-operative results and improve long-term outcomes.
Rigorous Parametric Dispersion Representation with Three-Channel Symmetry

Starting with an analyticity domain in the two Mandelstam variables which is contained in the domain obtained by Martin, we derive a parametric dispersion representation for scattering amplitudes in the equal-mass case. For pion-pion scattering this representation is a rigorous consequence of the axioms of local field theory; it displays in a symmetric and explicit way the contributions of all three channels, and it has only "physical" absorptive parts. This representation is useful for deriving sum rules involving only absorptive parts and relating all three channels. Some of these sum rules are given in this paper, the most important of which form a set of independent physical relations that lead to necessary and sufficient conditions ensuring full crossing symmetry.
Microbial Safety in Radio-frequency Processing of Packaged Foods

Thermal resistance of Colstridium sporegenes (PA 3679) was determined at 115,6 °C, 118.3 °C, and 121.1 °C (240 °F, 245 °F, and 250 °F, respectively) in phosphate buffer (pH 7.0) and mashed potatoes (pH 6.3) using aluminum thermal-death-time (TDT) tubes developed at Washington State Univ. D-values were 1.8, 1.1, and 0.62 min in phosphate buffer and 2.2, 1.1, and 0.61 min in mashed potatoes at 115.6 °C, 118.3 °C, and 121.1 °C, respectively. Z-values were 12 °C and 10 °C in phosphate buffer and mashed potatoes, respectively. The thermal inactivation kinetic results were then used to validate a novel thermal process based on 27.12 MHz radio frequency (RF) energy. Trays of mashed potatoes inocalated with PA 3679 were subjected to 3 processing levels; targel process (F 6 -4.3), under-target process (F 0 -2.4), and over-target process (F 0 -7.3). The microbial challenge test data showed that microbial destruction from the RF process agreed with the calculated sterilization values. This study suggests that thermal processes based on HF energy can produce safe and shelf-stable packaged foods.
Quantitative coronary angiography in regression trials: a review of methodologic considerations, endpoint selection, and limitations

Several quantitative angiographic methods (visual assessment, digital hand-held calipers, and automated edge detection) have been successfully used to assess coronary atherosclerosis regression. These methods are applicable for (1) continuous measures of disease progression and regression, including patient-based, segment-based, and lesion-based analyses; and (2) categorical assessment of disease progression and regression (the use of a predefined threshold to categorize the course of disease). Angiographic methods and criteria for assessing disease progression each have distinct advantages and disadvantages, which accounts for the methodologic diversity seen in clinical trials.
Urbanization and female football in Nigeria: history and struggle in a ‘man's game’

Social obstacles including colonisation, cultural inhibitions, and religious restrictions impact female participation in sports. In Nigeria, particularly, where urbanisation and women participation in football has increased, interest in studying women's football amid social obstacles continues to be important. Some of these obstacles included a British colonists’ edict prohibiting female football in the country. The edict stunted the growth of female football in the country. Today, religious prohibitions, along with several other obstacles, such as cultural inhibitions, in the northern part of the country, create additional fault lines in the game's development. Indeed, several of the obstacles are rife in women's football in Nigeria and deserving of academic investigation such as reported in this paper. The paper uses a critical discourse analysis of archived newspaper media to expose the struggle and resistance of female football from the mid-twentieth century to date. The analysis makes the female game...
Dysphagia Management: A Survey of School-Based Speech-Language Pathologists in Vermont

Purpose This study (a) gathered information about the kinds of dysphagia management services school-based speech-language pathologists (SLPs) provide, (b) examined the attitudes of SLPs related to dysphagia management, (c) compared the responses of SLPs on the basis of their experience working in a medical setting, and (d) investigated the relationship between SLPs' training and their confidence to provide dysphagia services. Method Fifty-two school-based SLPs practicing in Vermont responded to a survey designed to gather information on the variables of interest. Results Respondents reported a low incidence of students requiring dysphagia services and SLPs providing a wide range of dysphagia services. Results indicated variability in attitudes related to dysphagia management, but trends were also evident. Chief among them were SLPs' low levels of confidence to provide dysphagia services and the need for additional training in dysphagia management. SLPs who had experience in a medical setting reported grea...
Structure-activity analysis of human ghrelin O-acyltransferase reveals chemical determinants of ghrelin selectivity and acyl group recognition.

Ghrelin O-acyltransferase (GOAT) is an integral membrane acyltransferase responsible for catalyzing a serine-octanoylation posttranslational modification within the peptide hormone ghrelin. Ghrelin requires this octanoylation for its biological activity in stimulating appetite and in regulating other physiological pathways involved in energy balance. Blocking ghrelin acylation using GOAT inhibitors is a new potential avenue to treat health conditions impacted by ghrelin signaling, such as obesity and diabetes. Designing novel and potent GOAT inhibitors as potential therapeutics requires insight into the interactions between the ghrelin and octanoyl coenzyme A substrates and the GOAT active site. Through structure–activity investigation of ghrelin-mimetic peptide substrates and inhibitors, we have analyzed the amino acid selectivity of the enzyme as well as the functional groups involved in substrate recognition by human GOAT (hGOAT). This analysis reveals that hGOAT both prefers and tolerates a distinct s...
Correlation structure of random pressure fields

A random pressure field manifests different levels of load effects on structures and their components. Information on local point-to-point variation of pressure is essential for the design of cladding, or the building envelope system, whereas area averaged loads are important for the overall structural loads. Fundamental to the characterizations of pressure fields is their correlation structure which determines the resulting aerodynamic load effects. This paper focuses on the correlation structure of the pressure field on prismatic bodies of finite height immersed in turbulent boundary layer flows. Wind tunnel and numerical simulation data are utilized to study the correlation structure. Both unconditional and conditional correlations, i.e. correlation of unconditionally and conditionally sampled data, are discussed here in the light of their sensitivity to the relative location on the surface, body geometry and the approach flow characteristics.
Polarization-selective switching in holographically formed polymer dispersed liquid crystals

We have developed an optical stack of holographically formed polymer dispersed liquid-crystal (H-PDLC) devices that is fully operational with nonpolarized light sources. The device consists of two H-PDLC transmission gratings separated by a passive polarization rotator that can output a diffracted s-polarized, p-polarized, or s- and p-polarized beam simultaneously.
Simulation of fluid catalytic cracking operation

Abstract Since its introduction in 1942 the fluid catalytic cracking (FCC) has been the most important and widely used process for the production of gasoline from heavy distillates. In most refineries the capacity of the FCC unit is second only to that of the crude distillation unit. Often an FCC unit is referred to as the heart of a modern refinery oriented toward maximum production of gasoline. The basic step in the FCC process is the recirculation of the catalyst through the reactor, stripping and regenerator. In the reactor system the hydrocarbon feed is heated and cracked. Coke (or carbon) may be produced and may deposit on the catalyst reducing its activity and selectivity. When the catalyst is circulated to the regenerator carbon is burned off causing the heating of the catalyst before its return to the reactor part. The products from the reactor are separated in a main fractionator into gas and liquid streams normally including a recycle feed to the reactor. The operation of an FCC unit requires the manipulation of a large number of controlled variables affecting its performance. Major process variables such as reactor temperature, catalyst circulation rate, catalyst inventory and recycle feed rate can be varied to influence the product yields and to accomodate widely different feedstocks. Unpredictable variation can occur in feed stock, catalyst quality and equipment performance. Most normal variation can be accomodated by a small change in operating conditions. For a new plant, comparison of actual versus predicted performance provides a valuable check on the validity of the design correlations and a guide for future laboratory and engineering research. The objectives of the present work are to simplify the complicated FCC process variables and to develop a computer model to simulate the operation of an FCC at different conditions. This includes the prediction of the effects of the operating variables on the reactor product yields. These products include fuel gas, C 3 , C 4 gasoline, light gas oil and coke. The model provides a good base for troubleshooting and debottlenecking and may be useful in optimal control of the FCC.
Stayin’ alive: the 1970s and the last days of the working class

by Jefferson Cowie, New York, New Press, 2010, 464 pp., $27.95 (cloth), ISBN 978-1-56584-875-7 The 1970s were a decade that scholars ignored. They were sandwiched between the turbulent era of the 1...
Basis for chronostratigraphic classification of the Precambrian

Abstract It is urged that the same stratigraphic principles and the same basis for chronostratigraphic classification be used in the Precambrian as in other parts of the earth's stratigraphic column, although relative emphasis on different methods of age determination and time-correlation may reasonably vary, depending on their applicability in different parts of the column. The definition of the boundaries of each chronostratigraphic unit should lie in the rock strata themselves. The standard time-scope of each unit should be delimited by an upper and a lower type boundary point (boundary-stratotype), each in a specifically designated and identified stratigraphic section, chosen at a position to give the unit the greatest significance and to allow the best use of criteria of age and time-correlation in extending the boundary geographically as widely as possible away from the type at as nearly an isochronous position as possible. Schemes for dividing Precambrian time on the basis of clustering of radiometric age dates, or arbitrarily by equal time intervals in hundreds of millions of years, are commendable and may be very useful for current mapping, for indicating general age relationships, or for other purposes; but there are cautions to be considered, and such schemes should not be allowed to replace or impede efforts at classification procedures tied more closely to the rocks themselves. Regional or worldwide classification of the Precambrian should desirably rest on a firm foundation of local chronostratigraphy, starting preferably in areas where thick, relatively continuous, relatively undeformed, and relatively unmetamorphosed sequences of Precambrian strata are present. The Precambrian—Cambrian boundary should not be defined by such generalizations as “at the lowest occurrence of organized fossils” or “at the base of shelly fossils” which give boundaries that are continuously subject to change and obviously will vary in age from place to place. Rather, the definition should refer to a boundary-stratotype, which desirably may coincide in the type area with these or any other criteria that will help in the correlation of the boundary as an isochronous horizon worldwide, but will still preserve for it a stable standard. The term “Archeozoic”, although not replacing the much more widely used “Precambrian”, still may be revived usefully as a term significant of the stage of life development, paralleling Cenozoic, Mesozoic, and Paleozoic, and including all strata older than Cambrian, since we cannot now deny the possible existence of life as far back in time as the age of the oldest known rocks.
Comparative simulation studies of native and single-site mutant human beta-defensin-1 peptides.

Human defensins play important roles in a broad range of biological functions, such as microbial defense and immunity. Yet, little is known about their molecular properties, i.e. secondary structur...
Understanding Cultural Frames in the Multicultural Sales Organization: Prospects and Problems for the Sales Manager

Changes in social demographics, legislation, and wealth distribution have prompted modern sales organizations to recognize the importance of cultural diversity within customer markets and sales forces. Some sales forces have employed multicultural salespersons to aide their pursuit of multicultural target markets. Traditionally, organizations have conceptualized cultural identity as membership in one particular category, or frame, determined by race or nationality. However, modern transnational sales organizations actually include sales managers and sales subordinates who may identify with more than one cultural frame, or meaning system. These cultural frames present important prospects and problems for today's sales managers who interface with sales subordinates having compatible or incompatible cultural frames. Within the context of the sales manager and sales subordinate relationship, we present a 2 × 2 framework explaining the cross-cultural interfaces between individuals having one cultural frame (mo...
Advances in Imaging of the Cardiac Neuronal System

Left ventricular ejection fraction (LVEF) is a useful tool for stratifying risk for heart failure progression and life-threatening arrhythmic events. Yet, the clinical course of heart failure patients with severely reduced LVEF is variable, and the majority of patients who die suddenly do not have an LVEF ≤35%. A recently completed large multicenter trial, ADMIRE-HF, confirms that cardiac neuronal imaging with I-123 metaiodobenzylguanidine is an important independent predictor of heart failure progression and sudden cardiac death. Data from that study indicate that heart failure patients with severe impairment of cardiac sympathetic innervation are at highest risk for heart failure progression, heart failure patients with moderate impairment of sympathetic innervation are at highest risk for life-threatening arrhythmic events, and heart failure patients with preserved sympathetic innervation are at low risk for either death due to heart failure progression or sudden cardiac death.
Independently controllable dual-feed dual-beam phased array using piezoelectric transducers

A new independently controllable dual-feed dual-beam phased array has been designed and measured at Ka-band. Thirty-two planar microstrip patch antennas are used to form a two-dimensional 4 /spl times/ 8 array, and two radiating beams are obtained by feeding both sides of the patch array. Two piezoelectric transducers are used to control phase shifts for beam steering. Two beams with a beam squint at /spl plusmn/13/spl deg/ in the E-plane are steered in the H-plane independently. The measured gain and beam steering angle are 13 dBi and 20/spl deg/, respectively.
PHYSIOLOGICAL STUDIES IN INSULIN TREATMENT OF ACUTE SCHIZOPHRENIA THE CHOLINE ESTERASE ACTIVITY OF THE BLOOD SERUM

THE ROLE of acetyl choline as a chemical mediator in the autonomic nervous system and, perhaps, the central nervous system, on the one hand, and the role of choline esterase in splitting acetyl choline, on the other hand, have given rise to considerable speculation. The question whether or not the choline esterase activity of the blood serumexcercises any regulating function on autonomic activity is still undecided. Ginsberg, Kohn and Necheles (i) reviewed the status of investigations on these subjects previous to 1937. While many of the investigators quoted by these authors are inclined to see a definite relation between the autonomic nervous system and choline esterase activity, the investigations of Ginsberg and his collaborators led to the conclusion that “ the esterase level of the blood is a rather immobile, unresponsive bulwark against an excess of acetyl choline in the blood”.
Dependence of photorefractive beam fanning on beam parameters

Abstract We analyze steady state beam fanning in a bulk photorefractive material by first solving for the induced refractive index profile. Guidelines for the choice of beam parameters, that maximize or eliminate beam fanning, are provided.
Fiber coupling using graded-index rod lenses

The graded-index rod lens (GRIN lens) is useful in coupling between multimode optical fibers. Applications include connectors, switches, multiplexers, and branch couplers. In these devices, one GRIN lens collimates light from an input fiber, and a second lens collects the light and focuses it on an output fiber. This paper presents analyses of power losses in these devices resulting from lateral and angular misalignments and from the spacing between the lenses. It is found that the GRIN lens coupling system is very sensitive to angular alignment but is more tolerant of lateral errors and lens spacing.
Including planning activity in feature space distributes activation over a broader neuron population

In neuroprosthetic systems, decoding based on a sparse population of task-related neurons is impractical because micro-electrode arrays often drift gradually in the cortex. Since the neuronal population being recorded from is dynamic, it is favorable to have a larger number of neurons containing information relevant to movement decoding and to decrease the relative importance of individual neurons. We have shown that a feature space comprised of neural firing rates from planning as well as movement periods exists in a broader distribution of neurons, as compared to a feature space that is derived from the movement period alone. For this study, spike train data from 297 neurons located in Ml and PM areas was analyzed to validate the hypothesis. The data was from a rhesus monkey performing reach to grasp task with measured wrist supination/pronation. Artificial neural networks were used to model encoding of wrist angle, and a sensitivity analysis was performed to attribute the relative importance of the input neurons. A classifier trained on only the least important neurons, as determined by their relative contribution to the decoded variable, had an average 20% better decoding accuracy when the new method of feature selection was used. This indicates that there is valuable information content within the distributed neuronal population.
New Results for Bremsstrahlung and Pion Production in the Neutron-Proton System

Differential cross sections for the neutron-proton bremsstrahlung (np → npγ) and pion production (np → npπ0 and np → ppπ-) processes have been measured for the first time at the Los Alamos Neutron Science Center. A pulsed neutron beam, produced by 800 MeV protons incident on a tungsten spallation target, bombarded a liquid hydrogen target. The outgoing neutrons and protons (in the first two reactions) or pairs of protons (in the third reaction) were observed in coincidence in organic liquid or plastic and CsI(pure) detectors at angles between 12° and 32° on opposite sides of the beam. For each pair of nucleon angles, the angular distribution of the unobserved photons or pions was deduced from the data.
The presence of 5-hydroxytryptamine in the venom of Bufo marinus.

5-Hydroxytryptamin (Serotonin, Enteramin, Thrombocytin), das in neuerer Zeit aus Blut oder Gewebe verschiedener Tiere isoliert wurde, konnte nun auch unter Verwendung von Isotopentechnik und Papierchromatographie als unmethylierter Vorlaufer der schon bekannten Krotenbasen im Giftextrakt vonBufo marinus im Ausmasse von 0,1 % (bezogen auf trockenen Giftextrakt) nachgewiesen werden.
Variable strain rate sensitivity in an aluminum alloy: Response and constitutive modeling

Abstract The thermo-mechanical responses of Al 2024-T351 under uniaxial compression loading are presented. The strain rates include quasi-static regime (10 −4 to 1 s −1 ) and dynamic loading (10 3 s −1 ), at temperatures of 233 K, 296 K, 358 K, 422 K, and 505 K. Below certain threshold temperature, negligible strain rate sensitivity is observed during quasi-static regime, while significant strain rate sensitivity is measured at dynamic strain rates. Above threshold temperature, increasing strain rate sensitivity has been observed. Based on these observations, the Khan–Liu (KL) phenomenological constitutive model is proposed to predict the mechanical behavior of the alloy over wide ranges of strain rate and temperature. Correlations with this modified model are shown very close to the observed responses.
Lung mechanics in congenital heart disease with increased and decreased pulmonary blood flow

Respiratory rate, tidal volume, dynamic lung compliance, functional residual capacity, and pulmonary resistance were measured withim 24 hours of cardiac catheterization in 25 infants, 12 of whom had increased pulmonary blood flow and 13 of whom had decreased PBF. There were no differences in the two groups of patients with respect to VT and FRC. Respiratory rate and pulmonary resistance were higher in infants with increased PBF. Lung compliance was significantly lower in infants with increased PBF (4.9 ml/cm H2O) than in those with decreased PBF (8.9 ml/cm H2O) (P less than 0.01). The decrease in CL in infants with increased PBF significantly correlated with mean pulmonary artery pressure (r = 0.798). No correaltion was found between CL and left atrial pressure or magnitude of the left-to-right shunt. Compliance was normal in patients with increased PBF and normal PAP, suggesting that PAP and not PBF is the primary factor that affects CL in patients with intracardiac left-to-right shunts.
Laminated, sacrificial-poly MEMS technology in standard CMOS

Abstract We present a micro-machining technology which enables MEMS fabrication on standard CMOS with very dense electrical/mechanical integration. Micro-mechanical structures are fabricated alongside circuits on standard 0.5-μm 3-metal CMOS dice using four maskless dry-etch steps. The resulting laminated beams are made of CMOS metal and dielectric layers. Multi-conductor mechanical structures can carry multiple signals for actuation and sensing. Narrow vertical and lateral gaps enable efficient XYZ electrostatic actuation and fine capacitive position sensing. Experiments show that mechanical structures can be integrated 1.5 μm away from signal-processing circuits, resulting in very low parasitics, good system performance, and small die size.
Robot-assisted therapy for children with autism spectrum disorders

Our research is the exploration of the social effects of human-robot interaction (HRI) on children with ASD, a population that has deficiencies in many types of social behavior. Computers and robots have been shown to be a catalyst for increased social interaction in children with ASD, yet that effect requires further study to be effectively employed as a therapeutic intervention.
Application of Flow Field Flow Fractionation-ICPMS for the Study of Uranium Binding in Bacterial Cell Suspensions

Field flow fractionation (FFF) is a size-based separation technique applicable to biomolecules, colloids, and bacteria in solution. When interfaced with ICPMS on-line, elemental data can be collected concurrent with size distribution. We employed hyperlayer flow FFF (Fl FFF) methodology to separate cells of Shewanella oneidensis strain MR-1 from exopolymers present in washed cell suspensions. With a channel flow of 4 mL min-1 and a cross-flow of 0.4 mL min-1 cells eluted with a retention time of 4.7 min corresponding to an approximate equivalent spherical cell diameter of 0.8 μm. Cell suspensions were amended with increasing concentrations of U to establish an adsorption isotherm and with fixed U concentrations at varying pH to establish the pH dependence of sorption. A linear sorption isotherm was determined for U solution concentrations of 0.2−16 μM, maximum U sorption occurred at pH 5. A high molecular weight compound, presumably a cell exudate, was identified by Fl FFF-ICPMS. This cell exudate complex...
Impact of scaffold micro and macro architecture on Schwann cell proliferation under dynamic conditions in a rotating wall vessel bioreactor

Over the last decade tissue engineering has emerged as a powerful alternative to regenerate lost tissues owing to trauma or tumor. Evidence shows that Schwann cell containing scaffolds have improved performance in vivo as compared to scaffolds that depend on cellularization post implantation. However, owing to limited supply of cells from the patients themselves, several approaches have been taken to enhance cell proliferation rates to produce complete and uniform cellularization of scaffolds. The most common approach is the application of a bioreactor to enhance cell proliferation rate and therefore reduce the time needed to obtain sufficiently significant number of glial cells, prior to implantation. In this study, we show the application of a rotating wall bioreactor system for studying Schwann cell proliferation on nanofibrous spiral shaped scaffolds, prepared by solvent casting and salt leaching techniques. The scaffolds were fabricated from polycaprolactone (PCL), which has ideal mechanical properties and upon degradation does not produce acidic byproducts. The spiral scaffolds were coated with aligned or random nanofibers, produced by electrospinning, to provide a substrate that mimics the native extracellular matrix and the essential contact guidance cues. At the 4 day time point, an enhanced rate of cell proliferation was observed on the open structured nanofibrous spiral scaffolds in a rotating wall bioreactor, as compared to static culture conditions. However, the cell proliferation rate on the other contemporary scaffolds architectures such as the tubular and cylindrical scaffolds show reduced cell proliferation in the bioreactor as compared to static conditions, at the same time point. Moreover, the rotating wall bioreactor does not alter the orientation or the phenotype of the Schwann cells on the aligned nanofiber containing scaffolds, wherein, the cells remain aligned along the length of the scaffolds. Therefore, these open structured spiral scaffolds pre-cultured with Schwann cells, in bioreactors could potentially shorten the time needed for grafts for peripheral nerve regeneration.
Multiprotein Complex Formation at the β Myosin Heavy Chain Distal Muscle CAT Element Correlates with Slow Muscle Expression but Not Mechanical Overload Responsiveness

To examine the role of the β-myosin heavy chain (βMyHC) distal muscle CAT (MCAT) element in muscle fiber type-specific expression and mechanical overload (MOV) responsiveness, we conducted transgenic and in vitro experiments. In adult transgenic mice, mutation of the distal MCAT element led to significant reductions in chloramphenicol acetyltransferase (CAT) specific activity measured in control soleus and plantaris muscles when compared with wild type transgene β293WT but did not abolish MOV-induced CAT specific activity. Electrophoretic mobility shift assay revealed the formation of a specific low migrating nuclear protein complex (LMC) at the βMyHC MCAT element that was highly enriched only when using either MOV plantaris or control soleus nuclear extract. Scanning mutagenesis of the βMyHC distal MCAT element revealed that only the nucleotides comprising the core MCAT element were essential for LMC formation. The proteins within the LMC when using either MOV plantaris or control soleus nuclear extracts were antigenically related to nominal transcription enhancer factor 1 (NTEF-1), poly(ADP-ribose) polymerase (PARP), and Max. Only in vitro translated TEF-1 protein bound to the distal MCAT element, suggesting that this multiprotein complex is tethered to the DNA via TEF-1. Protein-protein interaction assays revealed interactions between nominal TEF-1, PARP, and Max. Our studies show that for transgene β293 the distal MCAT element is not required for MOV responsiveness but suggest that a multiprotein complex likely comprised of nominal TEF-1, PARP, and Max forms at this element to contribute to basal slow fiber expression.
Solar puzzles for radio astronomers

Radio Physics of the Sun. Edited by M. R. Kundu and T. E. Gergely. Pp.475. ISBN hbk 90-277-1120-8; ISBN pbk 90-277-1121-6. (Reidel: 1980.) Hbk Dfl.115, $60.50; pbk Dfl.55, $$28.95.
Chaotic third sound resonances

There are three independent phenomena that compete to determine the line shapes of third sound resonances in a circular cavity. First, anharmonic terms in the hydrodynamic equations of motion lead to the usual hysteresis on a mugti-valued response function. Second, wave coupling to vortices pinned in the film modify the resonant frequency as changes in the persistent current are induced. Finally, nonlinear dissipation can lead to saturation. The first two of these have been observed to resugt in continuous (not just transient) temporal behavior of the resonance amplitude with a fixed drive. Both cyclical and chaotic behaviors have been observed. The effects are dependent on the ability of the driven wave to either accelerate or decelerate the persistent current onto different amplitude branches of the mugti-valued resonance.