cssi/SciSciGPT-SciSciNet huggingface dataset:
The evolution of paired appendages in vertebrates: T-box genes in the zebrafish.

The presence of two sets of paired appendages is one of the defining features of jawed vertebrates. We are interested in identifying genetic systems that could have been responsible for the origin of the first set of such appendages, for their subsequent duplication at a different axial level, and/or for the generation of their distinct identities. It has been hypothesized that four genes of the T-box gene family (Tbx2–Tbx5) played important roles in the course of vertebrate limb evolution. To test this idea, we characterized the orthologs of tetrapod limb-expressed T-box genes from a teleost, Danio rerio. Here we report isolation of three of these genes, tbx2, tbx4, and tbx5. We found that their expression patterns are remarkably similar to those of their tetrapod counterparts. In particular, expression of tbx5 and tbx4 is restricted to pectoral and pelvic fin buds, respectively, while tbx2 can be detected at the anterior and posterior margins of the outgrowing fin buds. This, in combination with conserved expression patterns in other tissues, suggests that the last common ancestor of teleosts and tetrapods possessed all four of these limb-expressed T-box genes (Tbx2–Tbx5), and that these genes had already acquired, and have subsequently maintained, their gene-specific functions. Furthermore, this evidence provides molecular support for the notion that teleost pectoral and pelvic fins and tetrapod fore- and hindlimbs, respectively, are homologous structures, as suggested by comparative morphological analyses.
Being 'Lazy' and Slowing Down: Toward decolonizing time, our body, and pedagogy

In recent years, scholars have critiqued norms of neoliberal higher education (HE) by calling for embodied and anti-oppressive teaching and learning. Implicit in these accounts, but lacking elaboration, is a concern with reformulating the notion of ‘time’ and temporalities of academic life. Employing a coloniality perspective, this article argues that in order to reconnect our minds to our bodies and center embodied pedagogy in the classroom, we should disrupt Eurocentric notions of time that colonize our academic lives. I show how this entails slowing down and ‘being lazy’.
Finite-infinite element analysis of P- and SV-wave propagation in a semi-bounded medium

Abstract The propagation of P- and SV-waves in a half-space due to a line source is investigated numerically. Space discretization is performed by a combination of finite and infinite elements. For discretization in time domain the Newmark's difference method is applied. Three example problems are solved by an accepted method of analysis. Comparisons with other methods are presented and discussed.
Use of intraperitoneal 5-fluorouracil and chlorhexidine for prevention of recurrence of perforated colorectal carcinoma in a rat model

PURPOSE: Colorectal cancer is a prevalent and mortal disease, resulting in nearly 55,000 deaths in the United States annually. Preoperative or intraoperative spillage of tumor cells because of perforation occurs in up to 10 percent of cases. When this spillage occurs, the chance of recurrence and death is dramatically increased. METHODS: In an effort to reduce the chance of recurrence and death, we used a rat model to evaluate the efficacies of intraperitoneal 5-fluorouracil and chlorhexidine in reducing the incidence of recurrence. Rats were injected with 10 mg/kg azoxymethane subcutaneously weekly for 12 weeks to induce colorectal cancers. At 20 weeks, subtotal colectomies were performed on rats with colorectal tumors and without peritoneal implants or liver metastases. At the time of surgery, a cut portion of the tumor was placed in the abdomen for 30 minutes; the rats then randomly received peritoneal irrigation with 5-fluorouracil, chlorhexidine, or sterile water (control). Eight weeks postoperatively a necropsy was performed. At that time, obvious and suspected recurrences and the anastomotic area were sampled for histologic evaluation. RESULTS: Significant differences were seen with chlorhexidine vs. water for gross tumor (P = 0.05) and microscopic tumor (P 0.05). CONCLUSIONS: Use of chlorhexidine intraperitoneal therapy at the time of the operation for perforated colorectal cancer significantly decreases the frequency of gross tumor recurrence but not total recurrences. Intraperitoneal 5-fluorouracil does not significantly decrease recurrence and may increase the risk of abscess when used intraoperatively.
Modeling the time-varying volatility of the paper–bill spread

Abstract The spread between the rates on commercial paper and Treasury bills has received considerable attention in the literature for its role as an indicator of real economic activity. In this paper we empirically examine what happens when the volatility of the spread changes over time. We estimate a nonlinear model that enables us to discern the asymmetric impact of negative and positive shocks to the spread. We find that a positive shock has a larger impact on the volatility of the spread than does a negative shock.
957 THYMIC RESPONSE TO ENDOGENOUS AND EXOGENOUS STEROIDS IN PREMATURE NEWBORN INFANTS

Thymic response to corticosteroid therapy for RDS was studied by measuring thymic width vs. transverse thoracic diameter on AP chest radiographs of premature newborn infants. Thymic-thoracic ratio (TTR) was evaluated in A)22 normal prematures, B)43 infants with RDS who received hydrocortisone or placebo postnatally (Pediatrics 50:526, 1972) and C)30 infants at risk for RDS treated with maternal betamethasone or placebo. In group A, TTR was unrelated to gestational age and was significantly smaller (mean 0.35) than in patients of group B and C with RDS, P< 0.025. On Day 1, TTR of steroid-and placebo-injected infants in group B were nearly identical (mean 0.42, 0.43) and declined at similar rates during the following 3 days to 63 and 69 percent of their original value respectively. Infants in group C who received betamethasone had a lower incidence of RDS than those given placebo. The TTR was significantly greater in patients who developed RDS(mean 0.42) than in those with normal lungs(mean 0.35),P<0.05.No relationship was observed between TTR and prenatal steroid dose or blood corticosteroid levels. The association of a high TTR and RDS suggest that steroids may have a parallel effect on thymus size and the pathogenesis of RDS. Hence measurement of TTR soon after birth could help identification of infants likely to develop RDS.
Management of posterior fossa arteriovenous malformations.

Background: Posterior fossa arteriovenous malformations (AVMs) are rare vascular lesions, representing 7–15% of all intracranial AVMs. Although less frequent than supratentorial AVMs, they present higher rupture, morbidity, and mortality rates. Microsurgery, radiosurgery, and endovascular neurosurgery are treatment options for obliteration of those lesions. In this paper, we present a critical review of the literature about the management of posterior fossa AVM.
The inability to ignore auditory distractors as a function of visual task perceptual load.

Using a response competition paradigm, we investigated the ability to ignore target responsecompatible, target response-incompatible, and neutral visual and auditory distractors presented during a visual search task. The perceptual load model of attention (e.g., Lavie & Tsal, 1994) states that task-relevant processing load determines irrelevant distractor processing in such a way that increasing processing load prevents distractor processing. In three experiments, participants searched sets of one (easy search) or six (hard search) similar items. In Experiment 1, visual distractors influenced reaction time (RT) and accuracy only for easy searches, following the perceptual load model. Surprisingly, auditory distractors yielded larger distractor compatibility effects (median RT for incompatible trials minus median RT for compatible trials) for hard searches than for easy searches. In Experiments 2 and 3, during hard searches, consistent RT benefits with response-compatible and RT costs with response-incompatible auditory distractors occurred only for hard searches. We suggest that auditory distractors are processed regardless of visual perceptual load but that the ability to inhibit cross-modal influence from auditory distractors is reduced under high visual load.
Effects of Hyperoxia on the Nucleic Acid Contents of Developing Brain

Prolonged exposure of the newborn to elevated concentrations of exygen may intiate pathlogic changes in teh retina, but, except for inhibition of capillary growth, no abnormalities have been described in brain. Ambient hyperoxia has been reported to inhibit nucleic acid synthesis in mammalian tissue cultures. The present studies suggest that hyperoxia may have similar effects in the developing brain in vitro. Newborn puppies were bottle-raised in 80% oxygen; weight-matched littermates were raised similarly in air. Over a nine-day period the mean weight gain was the same in both groups. Three days after termination of the oxygen exposure cerebral cortex and white matte were analyzed for DNA and RNA contents. The results obtained in nine pairs of animals were as follows: Brain nucleic acid Pi concentration in mg P/100 g wet weight, mean + S.E.M. No differences were found histologic examinations of brain sections. These findings indicate that ambient hyperoxia may inhibit nucleic acid synthesis and cell proliferation in the deveoping dog brain.
Severe combined immunodeficiency with response to calcium lonophore: A possible membrane defect

Abstract A child with severe combined immunodeficiency (SCID) had lymphocytes which were unresponsive to antigenic or mitogenic stimuli. Unexpectedly, his lymphocytes developed a normal proliferative response to the ionophore A23187; A23187 is an agent which facilitates transfer of calcium into lymphocytes, bypassing physiologic membrane events and resulting in proliferation of normal human lymphocytes. The child may have a defect in membrane function either at or prior to the point of normal transfer of calcium into lymphocytes and other cells. Our data indicate that the defect in this child is different from that in another, more frequent form of SCID, i.e., that associated with thymic dysplasia.
Lessons Learned from an Emergency Bridge Replacement Project

The terrorist attack on September 11, 2001, and subsequent potential threats to U.S. transportation systems have presented an urgent need to develop emergency response plans to quickly react to the possible consequences of extreme events. Extreme events include terrorist attack as well as man-made and natural disasters such as explosions, fires, floods, and earthquakes. The objective of this research was to identify strategies and technologies to quickly restore the use of highway bridges, a critical component of the nation's transportation network, in case they are damaged or destroyed by extreme events. One of the tasks associated with this research was to conduct case studies of previous bridge replacements following extreme events. By studying these cases, the research team sought to identify and expand on lessons learned, address which actions did and did not work well given the circumstances of the incident, and incorporate lessons into the emergency response plan for highway bridges. This paper presents the findings from one of the case studies, the I-40 Webbers Falls Bridge in Oklahoma. DOI: 10.1061/ASCE0733-93642006132:4338 CE Database subject headings: Bridge construction; Bridges, highway; Terrorism; Damage assessments; Oklahoma; Replacement.
Bilinear system interconnections and generating series of weighted Petri nets

This paper has three objectives. The first objective is to provide a simpler proof concerning a sufficient condition due to Ferfera under which bilinearity is preserved for cascade interconnections. The next objective is to provide a specific counterexample to show that this condition does not apply to the feedback connection. The final objective is to show that the well-known correspondence between rational series and formal power series recognized by weighted finite-state automata can be generalized to produce a correspondence between the generating series of cascaded and feedback connected bilinear systems and a class of weighted Petri nets.
Drugs and Lactation Database: LactMed

The National Library of Medicine's Drugs and Lactation Database is an essential resource for any health care professional treating or answering the questions of breastfeeding women. It is available to anyone free of charge online through the TOXNET platform.
Is Neighborhood Context Differently Related to Externalizing Problems and Delinquency for Girls Compared with Boys

Although a number of reviews of gender differences in conduct problems and delinquency exist, this paper fills a gap in reviewing neighborhood influences on gender differences in conduct problems and delinquency. These influences are known to be important for boys in childhood and adolescence, but cannot be assumed to be influential in the same manner for girls. The paper starts with several conceptualizations of the association between gender, neighborhoods and juvenile delinquency. It then addresses 4 key questions. Is residing in a disadvantaged neighborhood associated with problem behavior in girls? Are neighborhood effects independent of girls' age? Are girls in disadvantaged neighborhoods exposed to more risk factors than girls in advantaged neighborhoods? Can mediating risk factors explain gender differences in neighborhood effects on children's and adolescents' conduct problems and delinquent behavior? Answers to these questions are important to steer research and elucidate aspects of interventions that can be optimized for girls.
BB0347, from the Lyme Disease Spirochete Borrelia burgdorferi, Is Surface Exposed and Interacts with the CS1 Heparin-Binding Domain of Human Fibronectin

The causative agent of Lyme disease, Borrelia burgdorferi, codes for several known fibronectin-binding proteins. Fibronectin a common the target of diverse bacterial pathogens, and has been shown to be essential in allowing for the development of certain disease states. Another borrelial protein, BB0347, has sequence similarity with these other known fibronectin-binding proteins, and may be important in Lyme disease pathogenesis. Herein, we perform an initial characterization of BB0347 via the use of molecular and biochemical techniques. We found that BB0347 is expressed, produced, and presented on the outer surface of intact B. burgdorferi. We also demonstrate that BB0347 has the potential to be important in Lyme disease progression, and have begun to characterize the nature of the interaction between human fibronectin and this bacterial protein. Further work is needed to define the role of this protein in the borrelial infection process.
Initiation of Sustained Rhythmic Activity by Single Propagated Action Potentials in Canine Cardiac Purkinje Fibers Exposed to Sodium-Free Solution or to Ouabain

Canine cardiac Purkinje fibers were exposed to sodium-free solutions containing 128 mM tetraethylammonium chloride and 16.2 mM calcium. Some fibers exposed to these solutions were spontaneously active. Other fibers were quiescent, but they could be thrown into sustained rhythmic activity by a single driven action potential; the sustained activity resulted from the depolarizing phase of an oscillatory after-potential. Premature action potentials often showed prolonged plateaus, and their repolarization continued to a more negative level than that seen during the regular sustained activity. This condition caused a temporary slowing of rhythm and, on rare occasions, a cessation of spontaneous activity. Other canine cardiac Purkinje fibers were exposed to normal Tyrode's solution containing 0.125 mg ouabain/liter. In such fibers driven activity caused progressive loss of resting potential. Concomitant with that loss of resting potential, oscillatory after-potentials appeared. These oscillatory after-potentials sometimes grew into sustained rhythmic activity that occurred at a level of resting potential at which the normal sodium-dependent upstroke was presumably inactivated.
Surface extended x-ray-absorption fine-structure study of the (1 monolayer Sb)/GaP(110) interface.

Sb L-edge absorption fine structure has been measured to study the bonding geometry of the (1 monolayer Sb)/GaP(110) interface. The polarization dependence of these measurements confirms that the Sb zigzag chains lie nearly parallel to the GaP surface. The Sb-P, Sb-Ga, and Sb-Sb bond lengths are determined to be 2.60\ifmmode\pm\else\textpm\fi{}0.05, 2.79\ifmmode\pm\else\textpm\fi{}0.05, and 2.88\ifmmode\pm\else\textpm\fi{}0.05 \AA{}, respectively. These values are better characterized by sums of covalent radii than by bond lengths determined in total-energy-minimization calculations.
Parallelization and Distribution of a Coupled Atmosphere–Ocean General Circulation Model

Abstract The distribution of a climate model across homogeneous and heterogeneous computer environments with nodes that can reside at geographically different locations is investigated. This scientific application consists of an atmospheric general circulation model (AGCM) coupled to an oceanic general circulation model (OGCM). Three levels of code decomposition are considered to achieve a high degree of parallelism and to mask communication with computation. First, the domains of both the gridpoint AGCM and OGCM are divided into subdomains for which calculations an carded out concurrently (domain decomposition). Second, the model is decomposed based on the diversity of tasks performed by its major components (task decompositions). Three such components are identified: (a) AGCM/physics which computes the effects on the grid-scale flow of subgrid-scale processes such as convection and turbulent mixing; (b) AGCM/dynamics, which computes the evolution of the flow governed by the primitive equations; and (c) ...
Factorial moments in a generalized lattice gas model.

We construct a simple multicomponent lattice gas model in one dimension in which each site can either be empty or occupied by at most one particle of any one of D species. Particles interact with a nearest-neighbor interaction which depends on the species involved. This model is capable of reproducing the relations between factorial moments observed in high-energy scattering experiments for moderate values of D. The factorial moments of the negative binomial distribution can be obtained exactly in the limit as D becomes large, and two suitable prescriptions involving randomly drawn nearest-neighbor interactions are given. These results indicate the need for considerable care in any attempt to extract information regarding possible critical phenomena from empirical factorial moments.
Complaining about chronic pain.

Abstract This paper examines how a group of working class people describes and experiences chronic pain. This hermeneutical–phenomenological study concentrates on the lived body of pain from three perspectives, drawing on interviews with 14 people who were attending a pain management program. First I consider the terms in which pain is circumscribed in the narratives, stories told in the context of learning to manage pain. These terms are polarities, ways of specifying and legitimating pain in relation to “mind” and “body.” Pain, in the discursive polarities that define it, is the private property of an individual, who must in some fashion prove that pain exists in an objective manner. The speaker, in this discourse, stands as the one responsible for the production of pain. In the second part, the analysis turns to what this discourse reveals about pain as a lived body phenomenon. Here the analysis centers upon the torment of having to inhabit the intolerable, upon how pain unmakes the lifeworld of the sufferer, and how, simultaneously, people make pain. The place of pain is the body, as body-in-place. The place of pain is at the boundaries of human dwelling, a kind of non-place, expressed metaphorically as “prison” or “homelessness.” Finally, after these considerations of how pain is described, in part three, I turn to the act of “saying” pain, that is, to the narratives as addressed to someone else. The participants were not simply dispensing information; they were saying something to me. The narratives had the form of complaints. The form of the narratives, in the context of the pain program, was a quasi-legal call to rectify wrongs.
Odorant stimulation of secretory and neural processes in the salamander olfactory mucosa.

1. Topical application of the odorants guaiacol (10−3 mol/l, 1–30 min) and 2-isobutyl-3-methoxypyrazine (IBMP, 10−5–10−3 mol/l, 15 min) caused time- and concentration-dependent reductions in the secretory granule content of acinar cells of the superficial Bowman's glands (sBG) and moderate to extensive vacuolation in acinar cells of sBG and deep olfactory glands (dG). 2. Topical application of 9.8 mg/ml scopolamine 10 min before 10−4 mol/l IBMP significantly reduced the amount of secretory granule depletion from sBG compared to that seen with IBMP alone and resulted in less extensive vacuolation in sBG and dG acinar cells. The i.p. injection of 42 mg/kg propranolol 10 min before topical application of 10−4 mol/l IBMP had no effect on the action of IBMP. 3. Guaiacol and IBMP also had time- and concentration-dependent effects on the secretory activity of sustentacular cells in the olfactory epithelium. The protrusion of secretory material into the mucociliary matrix that covers the epithelial surface and vacuolation within the secretory material resulted from odorant application. Scopolamine and propranolol had no effects on the action of IBMP on sustentacular cell secretory activity. 4. When applied in the vapor phase, guaiacol elicited action potentials recorded from individual olfactory receptor neurons; the impulse frequency was concentration-dependent and showed tonic and phasic components when the duration of stimulation was varied. Low to moderate concentrations of IBMP delivered in the vapor phase evoked monophasic negative slow voltage transients recorded from the surface of the olfactory mucosa. The amplitudes of these transients increased with increasing stimulus concentrations. Higher concentrations or longer stimulus durations evoked longer-latency positive-voltage generating processes and negative afterpotentials. The properties of the electrophysiological responses to both odorants were characteristic of responses evoked by a wide variety of ‘typical’ odorants.
Instanton calculations versus exact results in four dimensional SUSY gauge theories

Abstract We relate the non-perturbative exact results in supersymmetry to perturbation theory using several different methods: instanton calculations at weak or strong coupling, a method using gaugino condensation and another method relating strong and weak coupling. This allows many precise numerical checks of the consistency of these methods, especially the amplitude of instanton effects, and of the network of exact solutions in supersymmetry. However, there remain difficulties with the instanton computations at strong coupling.
Candidate comprehension of key concepts in kidney transplantation.

BACKGROUND Although kidney transplant candidates receive education regarding transplantation and donation, little is known about the extent of their comprehension. We aimed to identify factors that affect patient comprehension of important concepts regarding kidney transplantation. MATERIAL AND METHODS We performed a cross-sectional survey of consecutive adult kidney transplant candidates seen at our center between July 2013 and October 2013 for initial evaluation (n=100) or for reevaluation (n=117). The main outcome measure was a Knowledge Assessment Questionnaire completed by patients. We assessed factors affecting patient understanding of key kidney transplant concepts as measured by mean knowledge score. RESULTS Mean knowledge scores of those at evaluation (72±21) and those at reevaluation (70±20; p=0.4769) were similar; therefore the entire cohort was analyzed as a single group. Compared to the high-scoring group, low-scorers (<75%; median value) were significantly more likely to be older, Hispanic, with lower education attainment, and have end-stage renal disease due to hypertension or diabetes rather than other etiologies. On multivariate analysis, independent risk factors for low-scores were increasing age (aOR 1.03 (95% CI 1.01-1.06) and educational level (less than high school; aOR 4.23, 95%CI 1.82-9.80; high school or GED aOR2.85, 95% CI 1.43-5.70 compared to some college or technical school). Of 139 candidates that consented to receive ECD and 152 consenting to CDCHR kidneys, 52% and 27%, respectively, answered the high-risk-specific question incorrectly. CONCLUSIONS Educational level and older age are independent risk factors for poor comprehension. Kidney candidate knowledge of organs with increased risks is suboptimal despite previous consent to receive such organs.
The ILS as Outreach: Cataloging Campus Partner Collections

Although libraries tend to see the integrated library system (ILS) as a very “library” system, it is actually a powerful inventory and patron management system that can be used much more broadly. At American University, the library has many campus partner collections that it has added to the library catalog. Some collections contain books and media, like traditional library holdings, and some are made up of audiovisual and computer equipment. This article describes the process of cataloging these collections, the challenges of conceiving the ILS as a campus-wide system, and the benefits that these partnerships have brought to the library.
Reporting success rates in the treatment of vestibular schwannomas: Are we accounting for the natural history?

Stereotactic radiosurgery is generally accepted as one of the best treatment options for vestibular schwannomas. We question whether growth control is an accurate measure of success in vestibular schwannoma treatment. We aim to clarify the success rate of stereotactic radiosurgery and adjust the reported results to the benign natural history of untreated tumors. All articles were taken from a PubMed search of the English literature from the years 2000-2011. Inclusion criteria were articles containing the number of patients treated, radiation technique, average tumor size, follow-up time, and percentage of tumors growing during follow-up. Data were extracted from 19 articles. Success rates were adjusted using published data that 17% to 30% of vestibular schwannomas grow. The average reported success rate for stereotactic radiosurgery across all articles was 95.5%. When considering 17% or 30% natural growth without intervention, the adjusted success rates became 78.2% and 86.9% respectively. These rates were obtained by applying the natural history growth percentages to any tumors not reported to be growing before radiosurgical intervention. Success in the treatment of vestibular schwannomas with stereotactic radiosurgery is often defined as lack of further growth. Recent data on the natural growth history of vestibular schwannomas raise the question of whether this is the best definition of success. We have identified a lack of continuity regarding the reporting of success and emphasize the importance of the clarification of the success of radiosurgery to make informed decisions regarding the best treatment options for vestibular schwannoma.
Generalised sensitivity charts

One of the most important parts of the economic evaluation of industrial processes is sensitivity analysis. It assesses the effect on the process economics of various engineering and economic parameters. A widely used method of sensitivity analysis starts with defining a base or reference case and determining its economics in terms of a criterion, such as cost or profitability. Subsequently, one parameter at a time is varied over a range of values, and the corresponding changes in the selected criterion are estimated. In some cases, the investigator varies two related parameters at the same time. Assume, for example, that it is desired to investigate the effect on profitability of plant capacity, with all other independent variables unchanged. A higher capacity implies the increase in two parameters, capital cost and production, as opposed to the increase in production at constant capital, which can be denoted as attaining higher plant productivity. Capital and production are two distinct parameters. The former, an economic variable, affects cash flow primarily during the construction period; while production, an engineering variable, may have a major impact only after start-up. Rarely are more than two selected parameters varied at the same time in sensitivity analysis. The purpose of this analytical tool would be defeated, as the individual effects would become blurred. The variation of a
Periodontal management of the patient with diabetes mellitus

Diabetes mellitus is a common medical disorder that will be encountered by every practicing dentist. Knowledge by the dentist of the general and oral signs and symptoms of undiagnosed or poorly controlled diabetes mellitus are essential, and patients displaying these signs or symptoms should receive medical referral. Patients suspected, or known to suffer from undiagnosed or uncontrolled diabetes mellitus should receive only emergency care until their health status has been properly evaluated. In the event the degree of control of a known diabetic is unknown or the patient is poorly controlled, antibiotic therapy should be administered in conjunction with any necessary surgical procedure or in the presence of oral infection. The practitioner must be prepared to manage diabetic emergencies should they occur in the dental office, and hypoglycemic incidents are most likely. The developing therapies now available for medical management of diabetes mellitus suggest that this condition will be more effectively controlled in the future, but medical consultation is important to proper periodontal patient management. New evidence suggests that advanced periodontal disease may interfere with diabetes mellitus control and the physician should be made aware of the patient's periodontal status. Under most circumstances, the well-controlled diabetes mellitus patient can receive safe and effective periodontal therapy with some modification of office protocol, and there is little reason to anticipate that the controlled diabetes mellitus patient cannot look forward to a lifetime of periodontal health if proper and timely periodontal therapy is rendered and the patient maintains effective oral hygiene measures accompanied by appropriate supportive periodontal recall therapy.
Determination of Hydroxy-2-ethylenediaminetriacetic Acid (HEEDTA) and Fe-HEEDTA in Nutrient Solutions by Ion-Pair Reversed-Phase High-Performance Liquid Chromatography

Abstract A reversed-phase ion-pair liquid chromatography method for the accurate detection and determination of hydroxy-2-ethylenediaminetriacetic acid (HEEDTA) and Fe-HEEDTA has been developed. Three mobile phases containing 0.05 M tetrabutylammonium hydroxide, 0.05 M tetrabutylammonium bromide, or 0.05 M tetrabutylammonium bromide + phosphate buffer were employed in this method. Iron was added to each mobile phase after addition of the selected ion pair reagent to determine the amount of HEEDTA in both the free and/or the metal chelated forms at concentrations as low as 50 μM. The method depends on the formation of the iron chelate with HEEDTA in the mobile phase at pH 7. Calculation of the amounts of chelated HEEDTA with iron in the mobile phase was verified using the Geochem-PC computer program, which showed that 99.95% of HEEDTA was chelated to iron at pH 7.
High‐time resolution dayside convection monitoring by incoherent scatter radar and a sample application

[1] Convection and its changes, driven by the solar wind, are related to geomagnetic disturbances such as substorms, dynamic pressure disturbances and convection bays. Furthermore, convection is theoretically related to the evolution of the Harang electric field reversal (or “discontinuity”), which has been related observationally and theoretically to these disturbances. Interplanetary measurements generally used for studying and making associations of convection with disturbances are acceptable for statistical studies, but spatial structure and propagation timing errors due to the highly variable orientation of interplanetary structures create significant ambiguity for case studies and have prevented definitive understanding. Moreover, small but geoeffective structure in the solar wind may be missed by even multispacecraft observations. Direct observation of dayside convection with high time resolution offers a potential solution to this problem. In this paper, we demonstrate that Sondrestrom incoherent scatter radar (ISR) observations have the ability to accurately monitor the dayside convection with ∼2.5 min temporal resolution. The observations clearly show the dayside convection responses to IMF Bz, By and solar wind dynamic pressure variations and thus shed new light on how the magnetosphere and ionosphere respond to different external driving. Then, we illustrate an application of this technique by showing how it can be applied to study substorm triggering. We plan to use this technique in the future to study the relationships between convection, other geomagnetic disturbances, and the Harang reversal, as well as to evaluate the preceding convection strength and duration and the convection changes that lead to substorm onset.
Decision Boundaries in Two Dimensions for Target Detection in Hyperspectral Imagery

We present an approach to the problems of weak plume detection and sub-pixel target detection in hyperspectral imagery that operates in a two-dimensional space. In this space, one axis is a matched-filter projection of the data and the other axis is the magnitude of the residual after matched-filter subtraction. Although it is only two-dimensional, this space is rich enough to include several well-known signal detection algorithms, including the adaptive matched filter, the adaptive coherence estimator, and the finite-target matched filter. Because this space is only two-dimensional, adaptive machine learning methods can produce new plume detectors without being stymied by the curse of dimensionality. We investigate, in particular, the utility of the support vector machine for learning boundaries in this matched-filter-residual space, and compare the performance of the resulting nonlinearly adaptive detector to well-known alternatives.
Extracellular Deposition of Eosinophil Major Basic Protein in Orbital Histiocytosis X

Although eosinophils are prominent in orbital lesions of patients with histiocytosis X (Langerhans' cell histiocytosis), little is known of their pathogenic significance in the disease. To determine whether eosinophils degranulate and deposit toxic proteins in orbital histiocytosis X, the authors examined lesions by indirect immunofluorescence for localization of the core granule protein (major basic protein) outside of eosinophils. Four patients with histiocytosis X were studied: three with eosinophilic granuloma and one with Hand-Schuller-Christian disease. Tissue eosinophilia was prominent in all specimens; striking extracellular deposition of eosinophil major basic protein was noted in three patients, and focal deposition was present in the fourth patient. Orbital specimens obtained at autopsy from patients without orbital disease were studied as control specimens; no tissue eosinophilia or deposition of eosinophil major basic protein was observed. These findings indicate that eosinophils likely degranulate in lesions of orbital histiocytosis X and may participate in the pathogenesis of the disease.
Cytogenetic findings of a child with transcobalamin II deficiency

Transcobalamin II deficiency is a rare, probably autosomal recessive, inborn error of protein metabolism [Hakami et al., 1971]. Several authors have described the morphological characteristics of bone marrow aspirates from patients with this disorder; no reports have detailed the cytogenetic findings [Hitzig et al., 1974; Hakami et al., 1971; Niebrugge et al., 1982]. We report the cytogenetic findings of the bone marrow aspirates from an infant with transcobalamin II deficiency and identify fragile site expression in the hematopoietic cells in this patient.
Multiple B‐vitamin inadequacy amplifies alterations induced by folate depletion in p53 expression and its downstream effector MDM2

Folate is required for biological methylation and nucleotide synthesis, aberrations of which are thought to be the mechanisms that enhance colorectal carcinogenesis produced by folate inadequacy. These functions of folate also depend on the availability of other B-vitamins that participate in "one-carbon metabolism," including B2, B6 and B12. Our study therefore investigated whether combined dietary restriction of these vitamins amplifies aberrations in the epigenetic and genetic integrity of the p53 gene that is induced by folate depletion alone. Ninety-six mice were group pair-fed diets with different combinations of B-vitamin depletion over 10 weeks. DNA and RNA were extracted from epithelial cells isolated from the colon. Within the hypermutable region of p53 (exons 5-8), DNA strand breaks were induced within exons 6 and 8 by folate combined with B2, B6 and B12 restriction (p < 0.05); such effects were not significantly induced by mild folate depletion alone. Similarly, a minor degree of hypomethylation of exon 6 produced by isolated folate depletion was significantly amplified (p < or = 0.05) by simultaneous depletion of all 4 B-vitamins. Furthermore, the expression of p53 and MDM2 were significantly decreased (p < or = 0.05) by the combined depletion state but not by folate depletion alone. These data indicate that inadequacies of other 1-carbon vitamins may amplify aberrations of the p53 gene induced by folate depletion alone, implying that concurrent inadequacies in several of these vitamins may have added tumorigenic potential beyond that observed with isolated folate depletion.
The Marginal Costs and Benefits of Redistributing Income and the Willingness to Pay for Status

The effect of status on aggregate welfare is ambiguous for marginal reforms that redistribute income. If average consumption falls, the change in relative consumption increases household utility but reinforces the decrease in household labor supply, raising welfare cost. For parameterizations of the model developed here, reforms which lower average consumption increase aggregate welfare. Numerical calculations show that status increases marginal welfare cost and marginal net benefit for a demogrant reform. Redistributing to high income households may increase aggregate welfare depending on the definition of average consumption and if the willingness to pay for status increases with income.
Para-orthogonal Laurent polynomials and associated sequences of rational functions

On the space, Л, of Laurent polynomials (L-polynomials) we consider a linear functional ℒ which is positive definite on (0, ∞) and is defined in terms of a given bisequence, {μ k } −∞ ∞ . Two sequences of orthogonal L-polynomials, {Q n (z) 0 ∞ and $$\{ \hat Q_n (z)\} _0^\infty $$ , are constructed which span Λ in the order {1,z −1,z,z −2,z 2,...} and {1,z,z −1,z 2,z −2,...} respectively. Associated sequences of L-polynomials {P n (z) 0 ∞ , and $$\{ \hat P_n (z)\} _0^\infty $$ are introduced and we define rational functions $$M_n (z,w) = (P_n (z) + w\hat P_n (z))/(Q_n (z) + w\hat Q_n (z))$$ , wherew is a fixed positive number. The partial fraction decomposition and integral representation of,M n (z, w) are given and correspondence of {M n (z, w)} is discussed. We get additional solutions to the strong Stieltjes moment problem from subsequences of {M n (z, w)}. In particular when {μ k } −∞ ∞ is a log-normal bisequence, {M 2n (z, w)} and {M 2n+1 (z, w)} yield such solutions.
Reach for the Top: Women and the Changing Facts of Work Life

This article presents a review of the book “Reach for the Top: Women and the Changing Facts of Work Life,” edited by Nancy A. Nichols.
On symmetric stochastic convolutions

The notion of stochastic convolution arises from a study on various operations on probability measures. Although these operations appear in diverse branches of mathematics, their properties turn out to be similar. A general model for the study of such convolutions has been provided in earlier papers by the author. In this paper we consider some new properties of this model for convolutions corresponding to generalized integral transforms. The tools of this model can be applied to study many realizations of stochastic convolutions, for example, Urbanik's regular convolutions, the polynomial hypergroup's convolutions of Lasser, the convolution of Askey-Gasper and Levitan's convolution.
Seasonal dynamics and recruitment strategies of the invasive seaweed Grateloupia doryphora (Halymeniaceae, Rhodophyta) in Narragansett Bay and Rhode Island Sound, Rhode Island, USA

Although there is considerable interest in the introduction and spread of invasive species, there has been little research documenting growth patterns of a specific organism from the time of its fi...
Electron paramagnetic resonance investigation of donor impurities in CdZnTe grown by different techniques

Cadmium zinc telluride (CdZnTe) is being developed for room- temperature x-ray and gamma ray detectors. Identification and control of point defects and charge compensators are currently important issues. We have used electron paramagnetic resonance (EPR) and photo-induced EPR to evalute shallow-donor defects in CdZnTe crystal grown by two different techniques. Samples grown by the high-pressure Bridgman technique and a crystal grown by horizontal Bridgman at IMARAD and doped with indium were included in this study. Prior to the EPR investigations, we performed liquid-helium photoluminescence (PL) in order to examine the radiation recombination paths and identify the presence of other defects in these crystals. Spectra were obtained showing sharp excitonic lines, shallow and deep DAP emission bands, and a deeper 1.1 eV emission. The PL data help define the optical excitation range used in photo-EPR measurements. The photo-EPR data obtained from our samples is used to determine the concentration of isolated donor centers, while the EPR signal present under no illumination gives a measure of the net compensation. We also report the excitation wavelength dependence of the isotropic EPR signal from the shallow donors.
Sources of work motivation of business leaders in the USA and South Africa: a cross-cultural comparison using the Motivational Sources Inventory.

Summary Motivational differences in response to the Motivation Sources Inventory were tested between U.S. (n = 138) and South-African (n = 114) work samples. Analysis indicated that American managers scored significantly higher on intrinsic process (fun), while South-African managers scored significantly higher on self-concept external and goal internalization when measured using ratio analysis. Replication and extension with large groups representative of populations of interest in conjunction with Hofstede's cultural dimensions could allow generalization.
A model for electron/ion recombination in ionization chambers

The recombination of free electrons and positive ions along charged particle tracks in gases has been modeled using electron tranport equations, which assume homogeneous distribution in the vicinity of the tracks. The equations include space charge terms, which have been negelected in previous models. A formula for the electron yield as a function of detector applied potential is obtained from a perturbation solution valid when the ratio of the Debye length to the charge column radius is larger then unity. When this ratio is very large, the formula reduces to that of previous models. Pulse height measurements in a /sup 3/He ionization chamber indicate 2% to 30% losses to recombination which vary with applied field, particle type, and energy. Using reasonable values for the electron transport coefficients, the calculated loss of signal to recommendation is generally in agreement with experiment, but the variation with applied bias is stronger in the experiment.
Accuracy and nonoscillatory properties of enslaved difference schemes

We describe a general method for modifying a given finite-difference scheme by representing the effects of the subgrid scales in terms of the resolved scales through enslaving. The new scheme is more accurate in certain parameter regimes while retaining the time-step stability of the original scheme. We consider two general enslaving relations: an approximate enslaving based on truncation analysis and an exact enslaving based on the dynamics of the governing equation. We find that the modified schemes based on the exact enslaving eliminate unphysical oscillations, producing monotone solutions even when the original difference schemes do not, have this property. We offer a truncation analysis to justify this property. We apply our enslaving technique to advection-diffusion equations in both one and two spatial dimensions.
A Feed Additive to Control Flies in Poultry Manure

To determine methoprene's effect on fly emergence from poultry manure, 18,000 8-wk.-old caged pullets were fed continuously 10 gm. of methoprene per ton of feed 42 days. Hatch mates (13,500) in an adjacent, similarly constructed and equipped house were fed untrated feed. Data on fly emergence were recorded twice a week after counting average numbers of flies in fly traps, in buckets of manure, and on fly strips and spot cards. Differences between average counts in the treated and control groups were significant by each of the four data-gathering methods. The methoprene reduced fly emergence by 77.0% in manure buckets, 65.5% in fly traps, but increased fly emergence 19.2% on fly strips, and 92.2% on spot cards. We attribute the increases in fly counts by the latter two counting methods in the treated house to migration of flies from adjacent untreated houses.
Reliability of the WAIS-R with psychiatric inpatients.

WAIS-R subtest and composite scale reliabilities, standard errors of measurement, and standard errors of estimate were determined for a sample of psychiatric inpatients (N = 100). For Digit Span and Digit Symbol, test- retest stability coefficients were obtained; split-half reliability coefficients were calculated for all other subtests. With the exception of Object Assembly (rxx =.38), all subtest and composite scale reliability coefficients were large and acceptable. Based on the standard error of measure, the most reliable WAIS-R subtests were Digit Symbol (.77), Information (1.04), and Picture Completion (1.07). Reliability coefficients for the psychiatric inpatient sample were, in general, comparable to those values reported for the standardization group (Wechsler, 1981). Significant differences were obtained only on the Object Assembly and Vocabulary subtests.