cssi/SciSciGPT-SciSciNet huggingface dataset:
Relationship between Individual Personality Variables and Body Temperature Response Patterns in the Cold

While there is some evidence to indicate that strong and complex relationships exist between the psychological and physiological responses of human beings to stress-provoking stimuli (1, 6, 11, 12, 15, 18), much of this evidence is anecdotal or has been obtained using very small numbers of Ss. The present study was designed to provide additional information about, and substantiation of, the apparent relationships between certain psychological and physiological factors under stress, based on a large enough sample of Ss to permit adequate statistical treatment of the data. The study departs from conventional stress techniques in that it employs exposure to extreme temperature, in this case, cold, as the stress-provoking stimulus. From a qualitative analysis of some unpublished data concerning rectal temperature measurements in the cold: it is apparent that the differences between individual rates of recovery of "normal" rectal temperatures after removal from cold stress conditions are greater than the differences between individual rectal temperatures prior to and daring exposure to cold and that some of this variation can be accounted for by psychological factors, particularly the variability of the personality attributes of Ss. Most research involving rectal temperatures has focussed on pre-exposure and exposure periods (2, 5, 14, 17). The emphasis on the post-exposure measures of body temperature is based on the assumption that individuals, during exposure to a very stressful stimulus, differ less in their physiological responses to it than in their abilities to recover from it. In severe stress, the stimulus is apparently of sufficient magnitude to over-ride any individual differences in physiological response. Thus, for example, men placed nude in an ambient temperature of 30°F would show about the same patterns of skin cooling and internal body temperature change. Removal from exposure to the stressful stimulus should then allow individual differences in physiological structure and function to manifest themselves in different rates of recovery of thermal equilibrium. Therefore, recovery from exposure to stress appears to provide, at least on a logical basis, a better opportunity for study of the relationship of psychological variables with physiological
In situ 2-D piezoelectric wafer active sensors arrays for guided wave damage detection.

This paper presented development work of an in situ method for damage detection in thin-wall structures using embedded two-dimensional ultrasonic phased arrays. Piezoelectric wafer active sensors were used to generate and receive guided Lamb waves propagating in the plate-like structure. The development of a generic beamforming algorithm that does not require parallel ray assumption through using full wave propagation paths is described. A virtual beam steering method and device, the embedded ultrasonic structural radar, was implemented as a signal post-processing procedure. Several two-dimensional configurations were investigated and compared with beamforming simulation. Finally, rectangular shape arrays were developed for verifying the generic formulas and omnidirectionality. The rectangular arrays yield good directionality within the 360° full range and are able to detect damage anywhere in the entire plate.
Guest transport in a nonporous organic solid via dynamic van der Waals cooperativity

A well-known organic host compound undergoes single-crystal-to-single-crystal phase transitions upon guest uptake and release. Despite a lack of porosity of the material, guest transport through the solid occurs readily until a thermodynamically stable structure is achieved. In order to actively facilitate this dynamic process, the host molecules undergo significant positional and/or orientational rearrangement. This transformation of the host lattice is triggered by weak van der Waals interactions between the molecular components. In order for the material to maintain its macroscopic integrity, extensive cooperativity must exist between the molecules throughout the crystal, such that rearrangement can occur in a well-orchestrated fashion. We demonstrate here that even weak dispersive forces can exert a profound influence over solid-state dynamics.
Gothic memory and forgetfulness in Elizabeth Bowen's A World of Love and ‘The Demon Lover’

Elizabeth Bowen's A World of Love (1954) and ‘The Demon Lover’ (1945) share an uncustomary usage of Gothic conventions: the Anglo-Irish writer invests the Gothic genre with new meaning for the war-torn Irish and the post-World Wars generation by skewing Gothic conventions, reflecting a new Gothic for a new age – one that has seen the effects of two catastrophic wars and not only dead soldiers, but dead-in-life survivors. In A World of Love, Bowen uses not a ghost that haunts the attic, but a nearly forgotten dead World War I soldier; not a male power of place and a fleeing female, but a female power of place and a displaced male; and not a lonely, menacing castle, but a dilapidated farm. In both the novel and the short story, the dead-in-life survivors must remember in order to successfully exorcise the war and the dead soldiers of war, thereby revitalizing themselves. Those who cannot remember are doomed to the past. This article examines the twist on the Gothic novel and its statement about the possibly...
Coulomb T Matrix and Electron Capture by Protons Passing through Hydrogen

Using Nutt's expression for the two-particle off-shell Coulomb $T$ matrix, and neglecting multiple-scattering terms in Faddeev's expansion for the transition matrix, an expression for the charge-exchange amplitude in proton-hydrogen scattering is derived. The results of numerical calculations are compared with the corresponding results of Brinkman and Kramers, of Jackson and Schiff, and of Drisko. An analytical expression for the total cross section at high energies is obtained from our formalism. In the high-energy limit, our results approach the Brinkman-Kramers formula.
Development of taxonomic resources in the tropics.

The tropics abound with insect diversity; yet we hardly know about a tenth of them. Destruction of natural habitats due to deforestation, monoculture and urbanization results in their extermination or change of habits, often with devastating results. If the insects are to be properly managed for the benefit of mankind, an inventory of them should be taken before they are destroyed and their habits and habitats studied. A team of well trained taxonomists is required. Taxonomie centres are to be developed where taxonomists can be trained and insect collections can be housed and studied. Taxonomie manpower and resources should be developed in various countries of the tropics so that the rich and abundant insect diversity is studied and finally utilized for the benefit of mankind.
Three dimensional structure of bacterial pili

Crystallographic and associated biochemical and structural studies are in progress on the fiber-forming pilin proteins of the gonococcal pilus. Preparative scale purification procedures have been developed for the gonococcal pilin protein, which appear generally applicable to bacterial pilins. For three gonococcal pilin protein strains, we have obtained both reassembled pilus fibers and three-dimensional crystals. One needle-shaped crystal form of gonococcal C30 pilin diffracts beyond 3 A resolution using synchrotron x-ray radiation. A diffraction data set to 3.5 A resolution has been collected on these needle-shaped crystals (lattice spacings α = 125.4(3) b = 120.4(3), c = 26.61(4) A) in which the packing arrangement of the pilin subunits appears to resemble that seen in the pilus fibers using electron microscopy. X-ray diffraction data confirm our proposed model for the overall polypeptide fold of a pilin subunit, which is an antiparallel 4-α helix bundle similar to tobacco mosaic virus coat protein and myohemerythrin.
Isolating low frequency activity in EEG spectrum analysis

A method for isolating and removing very slow activity from EEG records prior to spectrum computation is presented. This is accomplished by an autoregressive filter whose frequency transfer characteristic can be easily controlled. Examples of spectra computed for various filter parameter values are shown.
DNA Isolation from Mammalian Samples

RNA can be extracted from cultured cells, peripheral blood, bone marrow, plasma, serum, body fluids, and fresh or frozen tissues. RNA can also be extracted from formalin-fixed paraffin-embedded (FFPE) tissues. Methods for RNA extraction can be divided into three groups: phenol/chloroform extraction, silica spin-column absorption, and isopycnic gradient centrifugation. Two different RNA isolation procedures are described in this unit. The first basic protocol describes a one-step isolation involving monophasic lysis with guanidine isothiocyanate and phenol followed by chloroform extraction. The second basic protocol describes a silica-column separation method for RNA isolation.
Arc characteristics in small-scale DC plasma arc furnaces using graphite cathodes

The characteristics of electric arcs using graphite cathodes operating in small-scale DC transferred-arc furnaces and an in-flight plasma reactor have heen investigated. The variation oh arc voltage with arc length at currents up to 1.5 kA has been studied. These characteristics are relevant to the engineering design and evaluation of DC plasma furnaces and reactors for the development of chemical and metallurgical processes.
On numerical integration of a class of singular perturbation problems

A three-point difference scheme recently proposed in Ref. 1 for the numerical solution of a class of linear, singularly perturbed, two-point boundary-value problems is investigated. The scheme is derived from a first-order approximation to the original problem with a small deviating argument. It is shown here that, in the limit, as the deviating argument tends to zero, the difference scheme converges to a one-sided approximation to the original singularly perturbed equation in conservation form. The limiting scheme is shown to be stable on any uniform grid. Therefore, no advantage arises from using the deviating argument, and the most accurate and efficient results are obtained with the deviation at its zero limit.
Existence and multiplicity of positive solutions for classes of singular elliptic PDEs

We consider the boundary value problem −Δu=ϕg(u)u−αin Ω,u=0on ∂Ω, where Ω⊂RN is a bounded domain, ϕ is a nonnegative function in L∞(Ω) such that ϕ>0 on some subset of Ω of positive measure, and g:[0,∞)→R is continuous. We establish the existence of three positive solutions when g(0)>0 (positone), the graph of sα+1g(s) is roughly S-shaped, and α>0. We also prove that there exists at least one positive solution when g(0) 0, and 0<α<1. We employ the method of sub-super solutions to prove our results.
EPIDERMAL FEATURES AND SILICA DEPOSITION IN LEMMAS AND AWNS OF ZIZANIA (GRAMINEAE)

In four species of Zizania (Gramineae: Oryzeae) epidermal features of pistillate and staminate lemmas, paleas, and awns were studied by scanning electron microscopy (SEM) and energy dispersive X-ray analysis. Features observed were silica bodies, siliceous papillae, pitted siliceous papillae, stomata, microhairs, and prickle hairs. Staminate lemmas have all of these features. Pistillate lemmas have silica bodies and prickle hairs, lack stomata, and differ among species in occurrences of microhairs and siliceous papillae and pitted siliceous papillae. Awns of pistillate lemmas have silica bodies, prickle hairs, microhairs, and stomata; therefore, they possess a more complete set of features than their attached lemmas. Shapes of silica bodies on pistillate lemmas differ among species. A taxonomic key based on SEM observation of pistillate lemmas separates the four species by the shapes of silica bodies, arrangement of prickle hairs, and occurrences of microhairs and siliceous papillae. The main silica-containing structures are silica bodies, siliceous papillae, pitted siliceous papillae, and to a lesser extent prickle hairs. Pitted siliceous papillae with circular raised rims are formed by collapse or exfoliation of the tops of siliceous papillae; these have not been previously described in grasses. Comparison of epidermal features in the lemmas and leaves of Zizania shows that the former lack three kinds of nonsilicified papillae and epicuticular wax that are present on the latter but the lemmas have siliceous papillae and pits that are absent in leaves. ZIZANIA (wild rice) is a genus of four species (following Dore, 1969) of aquatic grasses belonging to the tribe Oryzeae and native to North America and Asia. Zizania aquatica L. occurs most abundantly along the Atlantic coastal plain of the eastern United States. Zizania palustris L. (sometimes included in Z. aquatica, sens. lat.) is centered in the Great Lakes region and New England; its grains are a well-known item of food. Zizania texana Hitchcock occupies a very limited area in southcentral Texas where it is recognized as endangered (Terrell, Emery, and Beaty, 1978). The fourth species, Zizania latifolia (Griseb.) Turcz. ex Stapf, is native to eastern Asia. Zizania is monecious with pistillate spikelets in the upper part of the inflorescence and staminate spikelets in the lower part. Each spikelet has one floret consisting of two bracts usually interpreted as lemma and palea, with both glumes absent. Pistillate florets have somewhat indurate lemmas and paleas, similar to each other in shape and texture, and attached along
Macromolecular Cryocrystallography: Cooling, Mounting, Storage and Transportation of Crystals

Simple methods are presented for handling, mounting, storage and transportation of crystals at cryogenic temperatures. They are easy to learn and have a number of technical and operational advantages over currently popular methods. In particular, the temperature of the crystal throughout all manipulations is known; it is shown never to rise above that of the warmest component of the cryogenic system, typically the cold gas stream of the low-temperature apparatus. Crystals can be mounted and inspected in the home laboratory prior to transportation to a synchrotron, giving dramatic savings in experimental time and effort. Provided appropriate care is taken, crystals remain frost free throughout any number of mount–dismount cycles.
Serologic survey of selected zoonotic disease agents in black-tailed jack rabbits from western Texas.

A serologic survey for the agents of Rocky Mountain spotted fever (RMSF) (Rickettsia rickettsii), Borrelia spp. including the causative agent for Lyme disease (Borrelia burgdorferi), and plague (Yersinia pestis) was conducted on blood samples collected from 30 and 46 black-tailed jack rabbits (Lepus californicus) from an urban environment in Lubbock, Texas (USA) during winter 1987 and the following spring 1988, respectively. Antibody titers to the agents of RMSF and borreliosis were detected in sera of 28 and 1% of the jack rabbits, respectively. Neither organisms (rickettsiae and/or spirochetes) nor their associated antigens were detected in any of the tissue or whole blood samples; plague antibodies were not detected in the 76 jack rabbits sampled. Four of 18 ticks (Dermacentor parumapertus) removed from 12 jack rabbits were positive for RMSF using the fluorescent antibody test. The black-tailed jack rabbit is a common wildlife species living in close proximity to higher density human populations in man...
Effects of water temperature on experimentally-induced infections of juvenile white sturgeon (Acipenser transmontanus) with the white sturgeon iridovirus (WSIV)

The effect of four water temperatures (10, 14, 19 and 23°C) on mortality and selected health indicators of juvenile white sturgeon was assessed following a water-borne exposure to white sturgeon iridovirus (WSIV). The epithelium of gills, skin and olfactory organ were confirmed as targets of WSIV by viral infectivity assay and microscopic examination of stained tissue sections. The highest mortality rate of 3% day−1 occurred at 23°C, corresponding to a 50% survival time of 20 days. Flavobacterium spp. infections were most prevalent at 23°C and a cumulative mortality of 54% was attributed to combined WSIV and secondary bacterial infections. Conversely, at 10°C the daily mortality rate was 1% which was attributed primarily to WSIV. In addition, the highest cumulative mortality of 71% occurred at 10°C and corresponded with a 50% survival time of 70 days. Challenged fish reared at higher temperatures experienced acute transitory decreases in plasma protein, reduction of hepatosomatic index (HSI) and hematocrit and a more pronounced hyperplasia of the gill epithelium. Conversely, infected fish at lower water temperatures exhibited chronically depressed HSI, condition factors (K) and specific growth rates (G). Chronic emaciation at 10°C was associated with more severe and extensive lesions in the epithelial mucosa of the olfactory organ.
The shape of the hazard function for cancer incidence

A population-based cohort consisting of 126,141 men and 122,208 women born between 1874 and 1931 and at risk for breast or colorectal cancer after 1965 was identified by linking the Utah Population Data Base and the Utah Cancer Registry. The hazard function for cancer incidence is estimated from left truncated and right censored data based on the conditional likelihood. Four estimation procedures based on the conditional likelihood are used to estimate the age-specific hazard function from the data; these were the life-table method, a kernel method based on the Nelson Aalen estimator, a spline estimate, and a proportional hazards estimate based on splines with birth year as sole covariate. The results are consistent with an increasing hazard for both breast and colorectal cancer through age 85 or 90. After age 85 or 90, the hazard function for female breast and colorectal cancer may reach a plateua or decrease, although the hazard function for male colorectal cancer appears to continue to rise through age 105. The hazard function for both breast and colorectal cancer appears to be higher for more recent birth cohorts, with a more pronounced birth-cohort effect for breast cancer than for colorectal cancer. The age specific for colorectal cancer appears to be higher for men than for women. The shape of the hazard function for both breast and colorectal cancer appear to be consistent with a two-stage model for spontaneous carcinogenesis in which the initiation rate is constant or increasing. Inheritance of initiated cells appears to play a minor role.
Caloric restriction augments brain glutamic acid decarboxylase-65 and -67 expression

The ketogenic diet is a very low-carbohydrate, high-fat diet used to treat refractory epilepsy. We hypothesized that this diet may act by increasing expression of glutamic acid decarboxylase (GAD), the rate-limiting enzyme in gamma-aminobutyric acid (GABA) synthesis. Thus, we evaluated brain GAD levels in a well-established, seizure-suppressing, rodent model of the ketogenic diet. Because the diet is most effective when administered with a modest ( approximately 10%) calorie restriction, we studied three groups of animals: rats fed ad libitum standard rat chow (Ad lib-Std); calorie-restricted standard chow (CR-Std); and an isocaloric, calorie-restricted ketogenic diet (CR-Ket). We found that GAD67 mRNA was significantly increased in the inferior and superior colliculi and cerebellar cortex in both CR diet groups compared with control (e.g., by 45% in the superior colliculus and by 71% in the cerebellar cortex; P <.001). GAD65 mRNA was selectively increased in the superior colliculus and temporal cortex in both CR-Std and CR-Ket diet groups compared with ad lib controls. The only apparent CR-Ket-specific effect was a 30% increase in GAD67 mRNA in the striatum (P =.03). Enhanced GAD immunoreactivity was detected in parallel with the mRNA changes. These data clearly show that calorie restriction increases brain GAD65 and -67 expression in several brain regions, independent of ketogenic effects. These observations may explain why caloric restriction improves the efficacy of the ketogenic diet in treating epilepsy and suggest that diet modification might be useful in treatment of a number of brain disorders characterized by impaired GAD or GABA activity.
Incontinence following bladder neck reconstruction--is there a role for endoscopic management?

Purpose: Little has been reported concerning the efficacy of endoscopic injection of dextranomer/hyaluronic acid for the treatment of residual incontinence following bladder neck reconstruction. We present the experience of 2 institutions using endoscopic submucosal injection of dextranomer/hyaluronic acid to correct incontinence in patients who had previously undergone bladder neck reconstruction with or without concomitant enterocystoplasty.Materials and Methods: A retrospective chart review was performed with patient demographics, indications for treatment and outcomes recorded. All patients had adequate bladder capacity and compliance on maximized medical therapy before injection. Continence was defined as at least a 3-hour daytime dry interval, while improvement was defined as an increase in the daytime dry interval to at least 2 hours.Results: A total of 14 patients (10 females and 4 males) underwent 21 injections. At a median followup of 17 months 10 patients had successful results (6 continent, 4 ...
Evidence for a cortically mediated release from inhibition in the human cochlea.

Purpose: To determine cortical influence on the efferent medial olivocochlear bundle system. Research Design: The effects of attention on contralateral suppression (CS) of click-evoked otoacoustic emissions were measured. Study Sample: Fifteen normal-hearing listeners. Results: CS was greatest in the nonattending condition and decreased significantly when attending to the click or broadband noise suppressor. The effects of attention on CS were not frequency dependent or due to changes in recording noise measures. Conclusions: Attention to either the ipsilateral, evoking stimulus or the contralateral suppressor causes a top-down, cortically mediated release from inhibition at the level of the cochlea that is measurable with common audiologic protocols and instrumentation. Future studies assessing the effects of attention on CS of click-evoked otoacoustic emissions in normal controls and individuals with various auditory or attentional deficits may provide valuable information about the capabilities of the cortex to affect peripheral processing in a normal and/or pathological system.
Substrate characterization of the saccharomyces cerevisiae protein farnesyltransferase and type-I protein geranylgeranyltransferase

The in vitro substrate preferences of recombinant S. cerevisiae protein farnesyltransferase and type-I protein geranylgeranyl-transferase were determined. Proteins ending in 16 different CaaX sequences (C = cysteine, a = aliphatic amino acid, X = variable amino acids) were used to determine the protein substrate preferences of these S. cerevisiae prenyltransferases. The identities of the attached prenyl groups were confirmed by iodomethane treatment of prenylated substrates and reverse-phase HPLC. The CaaX preference of each recombinant yeast enzyme was found to be nearly identical to the reported preferences of purified mammalian protein farnesyltransferase and type-I protein geranylgeranyltransferase. S. cerevisiae farnesyltransferase preferentially farnesylated CaaX sequences ending in methionine, cysteine or serine. The farnesyltransferase also attached geranylgeranyl to some CaaX sequences ending in methionine, leucine and cysteine. The S. cerevisiae type-I geranylgeranyltransferase preferentially geranylgeranylated CaaX sequences ending in leucine and to a lesser degree methionine. Yeast extracts were found to contain prenylating activities identical to those observed with the recombinant enzymes. Farnesyltransferase activity in yeast extracts exceeded type-I geranylgeranyltransferase activity by at least 3-fold, resulting in prenylation of leucine-ending CaaX substrates with a mixture of 75% geranylgeranyl and 25% farnesyl. These results suggest that some substrate overlap may occur between the S. cerevisiae protein farnesyltransferase and the type-I protein geranylgeranyltransferase in vivo.
Renal Efficacy of Mitrofanoff Drainange in Boys with PUV

Purpose Boys with posterior urethral valves (PUV) progress to end stage renal failure (ESRF) in 1/4 cases. It has been hypothesized that Mitrofanoff formation and intermittent catheterization with overnight drainage protects renal function. This benefit has not been quantified. Mitrofanoff formation has been performed at our centre for many years. Boys with PUV who had Mitrofanoff formation were identified and renal status pre and post-op compared, as was age at onset of ESRF in the Mitrofanoff group compared to historical controls. Material and Methods A retrospective analysis of boys with PUV and Mitrofanoff formation was performed, and a database of (ESRF) patients searched. Firstly, comparison of pre and post Mitrofanoff renal function and hydronephrosis was made. Secondly the age (years) at which PUV boys progressed to ESRF with and without Mitrofanoff drainage was compared. Results given as mean±SEM. Statistical analysis was by paired or 2-sample students t-test as appropriate, p Results Mitrofanoff formation was performed in 25 PUV boys. Data for 19 patients pre-op and post-op creatinine (118±18 μmol/l vs. 125±22 μmol/l), was not significantly different, p=0.13. Hydronephrosis was significantly reduced in 26 renal units, pre-op 1.9±0.1 cm vs. post-op 1.1±0.1 cm, p Conclusions Short-term Mitrofanoff drainage of bladders in PUV boys reduces renal dilatation by 40%, but doesn't change renal function. Long-term Mitrofanoff drainage significantly delays the onset of ESRF in PUV boys by 5 years.
The Audience of the Nicomachean Ethics

The question, "Who is the audience of the Nicomachean Ethics?" is crucial for understanding Aristotle's political philosophy. Leo Strauss and Aristide Tessitore have both argued that it consisted in part of gentlemen who uncritically accepted the worth of moral virtue as the starting point and horizon of the inquiry. By contrast, I argue that Aristotle seeks a common starting point with his audience in a commitment to noble action. Aristotle connects the love of noble action with the pursuit of honor. Yet, while this pursuit led some of his students to value moral virtue, it led others to value mastery. I explain the audience's equivocal understanding of virtue by tracing it back to the psychic motivations of the pursuit of honor in ancient Greece. This account helps us better understand Aristotle's overall pedagogical strategy in the Ethics.
Turbulent Concentration Diffusion in Multiphase Flow

In multifluid multiphase flow models, the velocity of each phase is determined by its own momentum equation, which is coupled to the other phases by pairwise interphase drag forces proportional to velocity differences. When the drag coefficients are large, the phase velocities become nearly equal and the relative motion of the phases becomes diffusional rather than inertial. The multifluid momentum equations then reduce to a single momentum equation for the mixture and a system of linear relations that determine the small residual velocity differences between the phases. We derive such diffusional relations in a very general form that applies to nearly all multiphase flow models of this type. The simplest such models then reduce to “drift flux” models that exhibit pressure diffusion but not ordinary (Fick's law) diffusion driven by concentration gradients. The question then arises of how to consistently account for turbulent concentration diffusion in models of this type. This question is resolved by spec...
Joan Acker's review of the contributing papers, edited by Susan Sayce

Purpose – This commentary aims to review the contributing papers in this special issue.Design/methodology/approach – Papers are reviewed by Joan Acker in relation to her original work “Hierarchies, jobs, bodies: a theory of gendered organizations”.Findings – It is found that the articles make important contributions to the question of equality in organizations.Originality/value – This commentary serves as a reminder that academic work can contribute to a dialogue between academic generations, as is demonstrated throughout this special issue.
The Philosophical Transactions of the Royal Society of London , 1675–1975: A sociohistorical discourse analysis

This study traces the evolution of scientific research writing in English from 1675 to 1975. Two separate methods of discourse analysis – rhetorical analysis focusing on broad genre characteristics, and sociolinguistic register analysis – are applied to a large corpus of articles from the Philosophical Transactions of the Royal Society of London. The two sets of results are then interpreted vis-a-vis the Royal Society's social history to yield an integrated description. Findings indicate that: (a) research writing in the 17th – 18th centuries was substantially influenced by communicative norms of author-centered genteel conduct; (b) greater attention to methodology and precision in the interest of scientific specialization brought about pronounced textual changes in the 19th century, although gentlemanly norms were still in evidence; and (c) by the late 20th century, expanded theoretical description/discussions appear to have replaced experiments and methods as the rhetorical centerpiece of the research article. (Discourse analysis, rhetorical analysis, register, social studies of science, scientific writing, corpus linguistics)
Sperm cell architecture, insemination, and fertilization in the model fern, Ceratopteris richardii

Motile sperm cells of land plants are released directly into the environment and encounter numerous constraints on their way to the egg. Sperm cell organization, shape, size, and plasticity are crucial to the processes associated with fertilization. We conducted an ultrastructural investigation to detail insemination (sperm release, swimming and movement within the archegonium) and fertilization in the model fern Ceratopteris richardii. Gametophytes were grown from spores using sterile culture techniques and flooded in water when sexually mature. Materials were examined at different stages post-flooding. During insemination in C. richardii, the sperm cytoskeleton and flagella rearrange, and the coils of the cell extend while entering the neck canal. In this nearly linear configuration, the dense ridge, a densely compacted band of filaments presumed to be actin, expands to surround the leading edge of the sperm cell. This ridge fuses with the receptive site on the female gamete and is the sperm component that initiates contact with the egg nuclear envelope. All cellular components, except plastids, enter the egg cytoplasm. Sperm mitochondria are distinguishable from those of the egg because they are encased by two or three additional membranes and are sequestered from the zygote cytoplasm. During karyogamy, the sperm components, including the microtubule cytoskeleton (spline) and flagella, maintain their spatial integrity. Microtubules play key roles not only in sperm cell structure but also in facilitating karyogamy in this fern. After karyogamy is completed, microtubule arrays of the sperm cell and the components of the locomotory apparatus are disassembled. We provide the first demonstration of the likely involvement of sperm actin in egg penetration in land plants and new insights into the fate of paternal organelles. This study points to the roles sperm cell structure and dynamics play in the intricate processes of insemination and fertilization in land plants.
The V2 vasopressin receptor mutations and fluid homeostasis

Although three different G-protein coupled receptors have been identified for arginine vasopressin, a significant physiological role has been recognized only for the V2 subtype that controls water homeostasis. Identification of the gene encoding the V2 vasopressin (or antidiuretic hormone) receptor enabled researchers to test the hypothesis that mutations of this gene were responsible for X-linked recessive nephrogenic diabetes insipidus. The affected patients are unable to concentrate their urine and as a consequence live in constant danger of dehydration that can cause death, particularly in infancy, or lead to severe hypernatremia that can impair their intellectual and physical development. The danger of severe dehydration diminishes in the adult patients, although they remain highly susceptible to this condition for the rest of their lives.
Low‐energy electron measurements at Ganymede with the Galileo spacecraft: Probes of the magnetic topology

During the close flyby of Ganymede by the Galileo spacecraft on 6 September 1996 a plasma analyzer was used to obtain comprehensive measurements of the thermal electron plasmas in the vicinity of this moon. Our initial analyses are directed toward the character of energy influxes into Ganymede's polar caps and the pitch angle distributions for warm electrons in the energy range of 70 eV to 4.5 keV. The source of these electrons is Jupiter's plasma sheet within which Ganymede was embedded during the flyby. These electrons were present along the entire trajectory and provide the opportunity to use their pitch angle distributions with respect to the magnetic field in order to investigate the magnetic field topology at Ganymede. Observations of the loss cones for these pitch angle distributions are a simple means of determining whether or not a given magnetic field line intersects the moon's surface. It is found that the observed pitch angle distributions are inconsistent with the current magnetostatic model for the magnetic fields in the vicinity of Ganymede. Thus a major revision of this model is required that accounts for the contributions of the plasma dynamical interaction in order to achieve a more accurate assessment of an intrinsic magnetic moment in the interior of this moon. In addition, the electron energy fluxes into the polar cap at the time of flyby were measured to be about 1 erg/cm²-s, or a total of approximately 5 × 1016 ergs/s over each polar cap available for excitation and ionization of any atmosphere near the moon's surface.
Specific dermatoses of pregnancy: advances and controversies

Specific dermatoses of pregnancy include herpes (pemphigoid) gestationis, polymorphic eruption of pregnancy (also known as pruritic urticarial papules and plaques of pregnancy), prurigo of pregnancy and pruritic folliculitis of pregnancy. This article focuses on what is currently known about the epidemiology, clinical characteristics, etiopathogenesis and management of these disorders. Moreover, it discusses the intrahepatic cholestasis of pregnancy and ‘atopic eruption of pregnancy’, which were recently reclassified as specific dermatoses of pregnancy, as well as debates related to the prevalence and diagnostic criteria of the latter. Finally, it addresses the suggested overlap between ‘atopic eruption of pregnancy’ and specific dermatoses of pregnancy, such as prurigo and pruritic folliculitis.
A cosine operator approach to modelingL2(0,T; L2 (Γ))--Boundary input hyperbolic equations

This paper investigates the regularity properties of the solution of a second-order hyperbolic equation defined over a bounded domain ź with boundary Γ, under the action of a boundary forcing term inL2(0,T; L2(Γ)). Both Dirichlet and Neumann nonhomogeneous cases are considered. A functional analytic model based on cosine operator functions is presented, which provides an input-solution formula to be interpreted in appropriate topologies. With the help of this model, it is shown, for example, that the solution of the nonhomogeneous Dirichlet problem is inL2(0,T; L2(ź)), when ź is either a parallelepiped or a sphere, while the solution of the nonhomogeneous Neumann problem is inL2(0,T; H3/4-e(ź)) when ź is a parallelepiped and inL2(0,T; H2/3(ź) when ź is a sphere. The Dirichlet case for general domains is studied by means of pseudodifferential operator techniques.
Epigenetic analysis of laser capture microdissected fetal epithelia

Laser capture microdissection (LCM) is a superior method for nondestructive collection of specific cell populations from tissue sections. Although DNA, RNA, and protein have been analyzed from LCM-procured samples, epigenetic analyses, particularly of fetal, highly hydrated tissue, have not been attempted. A standardized protocol with quality assurance measures was established to procure cells by LCM of the medial edge epithelia (MEE) of the fetal palatal processes for isolation of intact microRNA for expression analyses and genomic DNA (gDNA) for CpG methylation analyses. MicroRNA preparations, obtained using the RNAqueous Micro kit (Life Technologies), exhibited better yields and higher quality than those obtained using the Arcturus PicoPure RNA Isolation kit (Life Technologies). The approach was validated using real-time polymerase chain reaction (PCR) to determine expression of selected microRNAs (miR-99a and miR-200b) and pyrosequencing to determine CpG methylation status of selected genes (Aph1a and Dkk4) in the MEE. These studies describe an optimized approach for employing LCM of epithelial cells from fresh frozen fetal tissue that enables quantitative analyses of microRNA expression levels and CpG methylation.
Oxygen consumption and body temperature in neotropical and temperate zone lungless salamanders (Amphibia: Plethodontidae)

1. Oxygen consumption of 14 neotropical and 12 temperate zone species of lungless salamanders (Amphibia: Plethodontidae) was measured in air at 5, 15, and 25°C. 2. Field body temperatures of tropical species decrease with increasing elevation; low altitude forms consistently experience temperatures above those of temperate zone plethodontids and may reach 30°C body temperature. 3. The effect of body size on metabolic rate is equivalent for both groups of salamanders at all temperatures (b=0.8), except for temperate zone forms at 5°C (b=0.6). 4. Tropical salamanders consume less oxygen than temperate zone salamanders of the same size at all temperatures. Weight-corrected metabolic rate at 15°C increases with minimum elevational range in the tropical species. 5. Oxygen consumption shows a greater temperature-related increase (Q10) from 15 to 23°C than from 5 to 15°C. This and other considerations imply that lunglessness may not restrict plethodontids to cooler microhabitats.
Unusual reactivity patterns in bis-triphenylalkoxyphosphonium salts

Abstract Alkoxyphosphonium triflates have been prepared and reacted with a number of nucleophiles. Only negatively charged nucleophiles initiate substitution reactions. Nucleophile association with the phosphorus entity, prior to nucleophilic displacement, is implied.
Calcium intake and prostate cancer among African Americans: effect modification by vitamin D receptor calcium absorption genotype.

High dietary intake of calcium has been classified as a probable cause of prostate cancer although the mechanism underlying the association between dietary calcium and prostate cancer risk is unclear. The vitamin D receptor (VDR) is a key regulator of calcium absorption. In the small intestine, VDR expression is regulated by the CDX-2 transcription factor, which binds a polymorphic site in the VDR gene promoter. We examined VDR Cdx2 genotype and calcium intake, assessed by a food frequency questionnaire, in 533 African American prostate cancer cases (256 with advanced stage at diagnosis, 277 with localized stage) and 250 African American controls who participated in the California Collaborative Prostate Cancer Study. We examined the effects of genotype, calcium intake, and diet-gene interactions by conditional logistic regression. Compared to men in the lowest quartile of calcium intake, men in the highest quartile had an approximately two-fold increased risk of localized and advanced prostate cancer (odds ratio [OR]= 2.20, 95% confidence interval [CI]= 1.40, 3.46), with a significant dose-response. Poor absorbers of calcium (VDR Cdx2 GG genotype) had a significantly lower risk of advanced prostate cancer (OR= 0.41, 95% CI = 0.19, 0.90). The gene-calcium interaction was statistically significant (p=0.03). Among men with calcium intake below the median (680 mg/day), carriers of the G allele had an approximately 50% decreased risk compared to men with the AA genotype. These findings suggest a link between prostate cancer risk and high intestinal absorption of calcium.
Gap detection in multiple narrow bands of noise as a function of spectral configuration.

This study sought to differentiate between the effect of stimulus bandwidth and the effect of number of activated auditory channels on gap detection in narrow bands of noise. The aim was to clarify the role of across‐frequency analysis in temporal processing. Experiment 1 established that when total noise bandwidth is held constant at 100 Hz, gap detection improves as stimulus energy is distributed to both lower and higher frequencies. Experiment 2a showed that the effect was smaller, or was absent, when the cumulative stimulus bandwidth was increased from 100 to 200 Hz. Experiment 2b confirmed that the benefit of spectral dispersion for the narrower cumulative bandwidth also held for a higher frequency region. The results suggest that in conditions where the cumulative stimulus bandwidth is relatively narrow and, concomitantly, gap detection is relatively poor, there is an advantage in dispersing the stimulus across a number of auditory channels. The advantage for the distribution of energy across a range of auditory channels may be offset when the spectral spacing of bands exceeds a critical value.
Preservice Elementary Teachers' Knowledge for Teaching the Associative Property of Multiplication: A Preliminary Analysis.

Abstract This study examines preservice elementary teachers’ (PTs) knowledge for teaching the associative property (AP) of multiplication. Results reveal that PTs hold a common misconception between the AP and commutative property (CP). Most PTs in our sample were unable to use concrete contexts (e.g., pictorial representations and word problems) to illustrate AP of multiplication conceptually, particularly due to a fragile understanding of the meaning of multiplication. The study also revealed that the textbooks used by PTs at both the university and elementary levels do not provide conceptual support for teaching AP of multiplication. Implications of findings are discussed.
Diving for PERLS: Working and Performance Portfolios for Evaluation and Reflection on Learning

Professional competence requires a commitment to lifelong learning, self-assessment, and excellence. Complex skills such as these require flexible and comprehensive teaching and assessment measures. We describe a combination of working and performance portfolios that both foster and evaluate the development of professional competence. We explain the conceptual and practical underpinnings that maximize the effectiveness of these tools. Drawing on experience with University of Washington residents, we identify 5 criteria that can help promote successful use of portfolios: separate working and performance functions of portfolios, developing a supportive climate, developing skills in faculty and residents, observing progress over time, and fostering mentorship opportunities.
Neurotensin-induced antinociception and hypothermia in mice: antagonism by TRH and structural analogs of TRH

Abstract Intracisternal (IC) administration of neurotensin (NT) in a dose of 10 μg produced a significant hypothermia and antinociception in the hot-plate test in mice. Both of these effects of IC NT were completely antagonized by concomitant administration of equimolar doses of thyrotropin-releasing hormone (TRH) and several TRH congeners including 3-methyl-His-TRH (pGlu-3-methyl-His-Pro-NH 2 ), MK-771 (pyro-2-aminoadipyl-histidyl-thiazolidine-4-carboxamide), β-ala-TRH (pGlu-His-Pro-β-ala-NH 2 ), and RX-77368 (pGlu-His-dimethyl-Pro-NH 2 ). The antagonism by TRH and TRH analogs on NT-induced hypothermia and antinociception was dose-dependent. Of particular interest was the finding that RX-77368 not only blocked the effects of NT but also produced hyperalgesia. It appears that TRH analogs that are more resistant to biologic degradation are, like TRH, capable of blocking NT-induced behaviors.
Application of Parallel Computing on Large Scale Atmospheric Nucleation

During the process of atmospheric nucleation, harmful substances may be generated, thus, it is with significant to conduct research on the process. In our previous work, some tools for visualization have already been developed. However, while the data set becomes larger, the computing time also increases accordingly. To make things worse, sometimes the visualization tool may become unstable due to some limitations, especially while calculating the similarity between molecules. In this paper, we will first propose an algorithm for calculating the similarity between two molecules. Then, in order to accelerate the parsing of data, the proposed algorithm will be implemented with parallel methods, and experimental results will show the improvement of the computing speed.
Possible reactivating and sensitizing action of neuromyally acting agents.

The effects of a bisquaternary oxamide, methoxyambenonium (Meamb), d-tubocurarine (d-tbc), and of an oxime, pyridine-2-aldoxime methiodide (P-2-AM), upon the frog neuromyal junction, treated by organophosphorus anticholinesterases, TEPP and DFP, were studied. The oxamide and d-tbc resembled P-2-AM and other reactivators in that they caused a return of the sustained tetanic response and of the post-tetanic potentiation, after these were blocked by TEPP or DFP. Ringer's solution was did not reverse these actions of the oxamides and of d-tbc. In these actions, these drugs resembled two types of reactivators, NaF and P-2-AM. The well-known marked prolongation of the endplate potential (e.p.p.) by TEPP or DFP was markedly shortened by the oxamide and by d-tbc. The former also increased the amplitude of the e.p.p. These effects were obtained whether the transmission was blocked by Mg or by d-tbc itself. The finding of earlier investigators that d-tbc lowers the amplitude but does not shorten the duration of the e.p.p. was confirmed. P-2-AM antagonized the d-tbc block of the twitch response, increased the amplitude but not the duration of the e.p.p. and augmented but did not prolong acetylcholine depolarization of the e.p. This effect, described in this laboratory as sensitization, and distinct from anticholinesterase action, is shown by several reactivators, oxamides and several other neuromyal facilitators. It is suggested that the actions of the oxamide and of d-tbc upon TEPP or DFP response of the neuromyal junction may be explained by their reactivation capacity. Conversely, reactivators may exhibit sensitizing and facilitating actions.
Not without a plan: Geography and natural history in the late eighteenth century

In this paper I propose to examine the main lines of investigation into a subject that naturalists of the late eighteenth century called geographical history.' Although the subject underwent a coherent internal development between 1770 and 1800, only with difficulty did naturalists relate that development to their normal interests. Within the essentialist tradition many naturalists considered problems of spatial organization to be peripheral to their central projects, the inventory of living form and the construction of a truly natural system. Among those who were comfortable with questions of organic distribution, the situation of the topic remained uncertain. In theory, these naturalists treated spatial organization as a secondary principle in the economy of nature; in practice, they subordinated organic distribution to purely formal relations, the affinities and analogies of systematics. In neither case did geographical history emerge as an independent form of discourse. Among the conceptual schemata opposing essentialism, none was more widely read than that of Buffon. In the Histoire naturelle zoogeographical problems occupy so central a position that it is