cssi/SciSciGPT-SciSciNet huggingface dataset:
Organochlorine pesticides, polychlorinated biphenyls, and mercury in osprey eggs―1970-79―and their relationships to shell thinning and productivity

Osprey (Pandion haliaetus) eggs were collected in 14 states in 1970–79 and analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), and mercury. Moderate shell thinning occurred in eggs from several areas. DDE was detected in all eggs, PCBs in 99%, DDD in 96%, dieldrin in 52%, and other compounds less frequently. Concentrations of DDT and its metabolites declined in eggs from Cape May County, New Jersey between 1970–72 and 1978–79. Eggs from New Jersey in the early 1970s contained the highest concentrations of DDE. Dieldrin concentrations declined in eggs from the Potomac River, Maryland during 1971–77. Five different contaminants were significantly negatively correlated with shell thickness; DDE was most closely correlated. Ten percent shell thinning was associated with 2.0 ppm DDE, 15% with 4.2 ppm, and 20% with 8.7 ppm in eggs collected from randomly selected nests before egg loss. Shell thickness could not be accurately predicted from DDE concentrations in eggs collected after failure to hatch, presumably because the eggs with the thinnest shells had been broken and were unavailable for sampling. DDE was also significantly negatively correlated with brood size. Other contaminants did not appear to adversely affect shell thickness or reproductive success.
Psychosocial effects on parents of raising a physically handicapped child

The present study assessed the personality styles, attitudes, perspectives, and coping strategies of 133 mothers and 93 fathers of diabetic, asthmatic, crystic fibrotic, and hearing-impaired children. Across measures, both the essential positive adjustment levels and special problems of the sample were demonstrated, such that they formed a distinct group whose functioning fell between that reported for either “normalℍ or poorly-adjusted parents. Furthermore, the presence of the ill child served as the primary contributor to these patterns, with types of illness providing a secondary but significant thrust to its exact extent and scope. Mothers consistently reported more problems and more involvement than fathers, which illustrated their differential roles within these particular families as well as their typical modes of response to the stress of the ill child. Without a doubt, the stress was taking its toll on the parents. Even though they still managed to cope, a focus on the parental needs is necessary in the total management program for the physically ill child.
Explaining heterogeneity in the child poverty rate among immigrant families: Differences by parental citizenship

Abstract Much of the debate about child poverty among immigrant families has centered on factors that place immigrant children at a high risk for poverty. What is missing in this debate and the literature is that children in immigrant families are economically heterogeneous and that children in naturalized families are doing as well as or better than children in native families in terms of economic status. To examine the heterogeneous economic status of children in immigrant families, this study compared children's poverty rates by parental nativity and citizenship status, decomposing demographic risk factors of child poverty. The results indicate that whereas lower parental education and employment status largely explain the relatively higher poverty rate among children in noncitizen families, higher parental education and employment rates and a lower rate of single parenthood explain why children in naturalized families have a lower rate of poverty than those in noncitizen families. Implications of these findings are discussed in detail.
The social and work context of commercial sex between men: a research note:

A qualitative approach was used to explore the social and work contexts of the commercial sexual encounter between male sex workers and their clients. Male sex workers aged between 19 and 34 were interviewed in Melbourne. This preliminary, exploratory study suggests that dominant traditional models of male sexuality and masculinity may be reflected in how male sex workers give meaning to commercial sex. The study also reveals that, by using a career orientation towards their work, male sex workers may be able to separate work sex from personal sex, understand their work within the broader social context of work, reject the stigma of commercial sex, use their bodies as a resource that allows them to capitalise on male sexual privilege, and practise safe sex with their clients. Suggestions for further research into safe sex negotiations and practices in male commercial sex encounters are outlined.
Response of Skeletal Progenitor Cells to Fracture Injury in a Mouse Model

METHODS: BD-MSCswereobtained from theperipheral bloodof 810week-oldCD1wild type or FVB-Tg(CAG-luc,-GFP)L2G85Chco/ J mice, which express firefly luciferase and cytoplasmic eGFP constitutively in all cells, by a novel method utilizingOptiPrep density gradient isolation and hepatocyte stimulation. Cells were characterized by fluorescence-activated cell sorting (FACS). For calvarial defect healing, cells (5.0x105) were seeded onto hydroxyapatite-poly(lactic-co-glycolic acid) (HA-PLGA) scaffolds and placed onto critical-sized (4 mm) calvarial defects on CD1 athymic nude mice. For wound healing, BDMSCs were seeded onto pullulan-collagen composite dermal hydrogels, and transplanted (2.5 105 cells per wound) onto 6 mm splinted full thickness excisional wounds on the dorsum of FVB/NJ mice.
WEIGHTED MAXIMUM OVER MINIMUM MODULUS OF POLYNOMIALS, APPLIED TO RAY SEQUENCES OF PADÉ APPROXIMANTS

Let a≥ 0 , ɛ >0 . We use potential theory to obtain a sharp lower bound for the linear Lebesgue measure of the set Open image in new window. Here P is an arbitrary polynomial of degree ≤ n . We then apply this to diagonal and ray Pade sequences for functions analytic (or meromorphic) in the unit ball. For example, we show that the diagonal \left{ [n/n]\right} n=1∞ sequence provides good approximation on almost one-eighth of the circles centre 0 , and the \left{ [2n/n]\right} n=1∞ sequence on almost one-quarter of such circles.
Confocal images of circulating tumor cells obtained using a methodology and technology that removes normal cells.

A completely negative enrichment technology was used to detect circulating tumor cells, CTCs, in the peripheral blood of head and neck cancer patients. Of 32 blood samples, 63% contained CTCs and the number of CTCs identified per mL of blood collected ranged from 0 to 214. The final purity ranged from 1 CTC in 9 total cells to 1 CTC in 20,000 total cells, the final purity being both a function of the number of CTCs and the performance of the specific enrichment. Consistent with previous reports, CTC were positively identified if: (1) they contained a nucleus based on DAPI stain, (2) stained positive for cytokeratins, and (3) have a high nuclei to cytoplasmic ratio. In addition, for a blood sample to be considered positive for CTCs, the enriched sample must be positive for epithelial growth factor receptor, EGFR, as measured by RT-PCR. While most of the blood samples were obtained during surgery, a number were taken prior to and during surgery. In all of the pre- and postsurgery paired samples, significant...
pH‐responsive hydrogels with dispersed hydrophobic nanoparticles for the delivery of hydrophobic therapeutic agents

To investigate the delivery of hydrophobic therapeutic agents, a new class of polymer carriers was synthesized. These carriers are composed of two components: (i) a pH-responsive hydrogel composed of methacrylic acid grafted with poly(ethylene glycol) tethers, P(MAA-g-EG), and (ii) hydrophobic poly(methyl methacrylate) (PMMA) nanoparticles. Before the P(MAA-g-EG) hydrogel was crosslinked, PMMA nanoparticles were added to the solution and upon exposure to UV light they were photoencapsulated throughout the P(MAA-g-EG) hydrogel structure. The pH-responsive behavior of P(MAA-g-EG) is capable of triggered release of a loaded therapeutic agent, such as a low molecular weight drug or protein, when it passes from the stomach (low pH) to upper small intestine (neutral pH). The introduction of PMMA nanoparticles into the hydrogel structure affected the swelling behavior, therapeutic agent loading efficiency, and solute release profiles. In equilibrium swelling conditions the swelling ratio of nanoparticle-containing hydrogels decreased with increasing nanoparticle content. Loading efficiencies of the model therapeutic agent fluorescein ranged from 38 – 51 % and increased with increasing hydrophobic content. Release studies from neat P(MAA-g-EG) and the ensuing P(MAA-g-EG) hydrogels containing nanoparticles indicated that the transition from low pH (2.0) to neutral pH (7.0) triggered fluorescein release. Maximum fluorescein release depended on the structure and hydrophobicity of the carriers used in these studies.
Deconvolution of axisymmetric flame properties using Tikhonov regularization

We present a method based on Tikhonov regularization for solving one-dimensional inverse tomography problems that arise in combustion applications. In this technique, Tikhonov regularization transforms the ill-conditioned set of equations generated by onion-peeling deconvolution into a well-conditioned set that is less susceptible to measurement errors that arise in experimental settings. The performance of this method is compared to that of onion-peeling and Abel three-point deconvolution by solving for a known field variable distribution from projected data contaminated with an artificially generated error. The results show that Tikhonov deconvolution provides a more accurate field distribution than onion-peeling and Abel three-point deconvolution and is more stable than the other two methods as the distance between projected data points decreases.
Quantitative Differentiation: A General Formulation

Let dx denote Lebesgue measure on . With respect to the measure on the collection of balls , the subcollection of balls has infinite measure. Let have bounded gradient, . For any there is a natural scale-invariant quantity that measures the deviation of from being an affine linear function. The most basic case of quantitative differentiation (due to Peter Jones) asserts that for all , the measure of the collection of balls on which the deviation from linearity is is finite and controlled by , independent of the particular function . The purpose of this paper is to explain the sense in which this model case is actually a particular instance of a general phenomenon that is present in many different geometric/analytic contexts. Essentially, in each case that fits the framework, to prove the relevant quantitative differentiation theorem, it suffices to verify that the family of relative defects is monotone and coercive. We indicate one recent application to theoretical computer science and others to partial regularity theory in geometric analysis and nonlinear PDEs. © 2012 Wiley Periodicals, Inc.
Impression test—A review

Abstract Indentation test using a cylindrical indenter with a flat end is now known as impression test. The advantage is its capability to reach a steady state for creep test at constant load and it is possible to compare with the conventional tensile or compression tests. The test is simple and all the temperature and strain rate dependences can be obtained locally from one sample avoiding the sample to sample variations. It became very popular in the last decade. The literature is reviewed here.
Identifying the impacts of NASPAA's MPA standards and peer review process on education for the public service: 1975 - 1985

Since 1975, the NASPAA MPA Standards have been available to provide direction and focus to professional education for the public service. Based on a mail questionnaire sent to 202 NASPAA principal respresentatives, this study identifies and analyzes the impacts of the Standards upon NASPAA member programs. The 104 respondents perceived the greatest impacts on factors related to curriculum and program jurisdiction. The perceived level of impact was not significantly different when correlated against a number of demographic variables except in the case of programs which were considered to be “prestigious” Respondents from such programs perceived significantly lower impacts. The role and impact of the NASPAA MPA Standards is evident, yet limited. Additional study is suggested to determine reasons for the low levels of perceived impact in areas of faculty, student qualifications and services, supportive services, and off-campus programs and on how well the Standards have succeeded in providing recognition for...
Synthesis and cationic photopolymerization of 1-butenyl and 1-pentenyl ethers

Several 1-butenyl and 1-pentenyl ether monomers were prepared by the ruthenium catalyzed multistage double bond isomerization of the corresponding 3-butenyl and 4-pentenyl ethers and characterized. Employing tris(triphenylphosphine)ruthenium(II) dichloride as a catalyst, the isomerization of octyl 4-pentenyl ether to octyl 1-pentenyl ether in 60% yield could be achieved in 110 min at 200–205°C. Under similar conditions, 3-butenyl octyl ether was isomerized to 1-butenyl octyl ether in greater than 99% yield. The reactivities of both types of monomers in photoinitiated cationic polymerization were determined using real-time infrared spectroscopy and the monomers were found to polymerize at very nearly the same rate in the presence of a diaryliodonium salt photoinitiator. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 199–209, 1999
The Relativistic Vlasov‐Maxwell System in Two Space Dimensions: Part II

The motion of a collisionless plasma is modeled by the Vlasov‐Maxwell system. For the relativistic Vlasov‐Maxwell system in the plane with smooth initial data, bounds on particle speeds are derived. In an earlier work [10] it was shown that solutions remain smooth as long as particle speeds do not approach the speed of light. When these results are combined, it follows that solutions remain smooth for all time.
Formation of circular satellite tobacco ringspot virus RNA in protoplasts transiently expressing the linear RNA.

The most abundant form of the satellite RNA of tobacco ringspot virus (sTRSV RNA) is a linear, unit length molecule of 359 nucleotide residues, designated L−(+)M. A postulated replication scheme for the satellite RNA has as its first, and apparently virus-independent, step the ligation of L−(+)M into the corresponding circular form C−(+)M. We transiently expressed L−(+)M wild type and L−(+)M mutants in tobacco protoplasts using an African cassava mosaic geminivirus vector. Measured extents of C−(+)M accumulation were correlated with computer-predicted folding to suggest wild-type secondary structure elements that might be deleted without reducing ligation. A 127-nucleotide residue mutant L−(+)M was created by replacing, with 7 and 3 residues, respectively, nucleotide residues 53–211 and 268–350, each of which was predicted to form a set of three adjacent imperfect stem-loops in wild-type L−(+)M. The mutant L−(+)M was found to be extensively ligated to C−(+)M in protoplasts and to retain a calculated helix of the wild-type molecule that incorporates the 3′ terminal sequence. A trinucleotide in the 3′ region was mutated so as to disrupt and restore, respectively, the calculated helix, reducing and restoring, respectively, C−(+)M formation. These results suggest that the 3′ stem contributes to the suitability of the small L−(+)M molecules as a substrate for a protoplast RNA ligase and that computed folding of sTRSV RNA may be predictive of sTRSV RNA structurein vivo.
The remodeling transient and the calcium economy.

Summary The remodeling transient describes a change in bone mass that lasts one remodeling cycle following an intervention that disturbs the calcium economy. We demonstrated the transient in a study of the response of bone density to calcium/vitamin D3 supplementation and show the hazards of misinterpretation if the transient is not considered.
Are certain preschoolers at risk in the era of welfare reform? The moderating role of children's temperament

Abstract The current investigation examined whether two dimensions of children's temperament—effortful control and negative emotionality—moderated links between mothers' welfare and work transitions and preschoolers' developmental trajectories (N = 445). Data were drawn from a sample of low-income, predominantly ethnic minority children and their mothers, when children were ages 2–4, and again 16 months later. Among children whose mothers' left welfare or entered work, high effortful control and low negative emotionality were not protective factors in children's socioemotional or cognitive functioning. However, when mothers experienced job loss or entered the welfare system, preschoolers with high effortful control displayed better developmental outcomes over time than children with low effortful control.
Synthesis and Characterization of Well-Defined 12,12-Ammonium Ionenes: Evaluating Mechanical Properties as a Function of Molecular Weight

Water-soluble 12,12-ammonium ionenes were prepared via the Menschutkin reaction from 1,12-dibromododecane and 1,12-bis(N,N-dimethylamino)dodecane. A stoichiometric imbalance of monomers controlled the final molecular weights of the polymers. The absolute molecular weights were determined for the first time using an online multiangle laser light scattering (MALLS) detector in aqueous size exclusion chromatography (SEC). Weight-average molecular weights ranged from 4300 to 20 900 g/mol. Relationships between weight-average molecular weight and mechanical properties were established for a series of 12,12-ammonium ionenes using both tensile testing and dynamic mechanical analysis (DMA). Tensile analysis of the higher molecular weight ionenes revealed an average tensile strength of 20 MPa and elongations ranging from 230 to 440%. Dissociation of ionic aggregates was observed at 85−88 °C in DMA experiments, and the glass transition temperatures increased with increasing molecular weight (61−88 °C). X-ray scatte...
Individuality of DNA denaturation patterns in human sperm as measured by the sperm chromatin structure assay.

Eight monthly semen samples from 45 men not known to be exposed to industrial toxicants were measured by the flow cytometric sperm chromatin structure assay (SCSA). This assay determines susceptibility of sperm DNA to in situ, acid-induced denaturation and is quantitated by the metachromatic shift of acridine orange fluorescence from green (native DNA) to red (denatured DNA). The observed green versus red fluorescence scattergram (cytogram) patterns were generally unique between donors and homogeneous within a donor over time. Within a donor, the cytogram patterns were the same whether intact sperm cells or detached nuclei were measured. For some individuals the cytogram patterns differed for some months and then returned to the original pattern. Intraclass correlations for mean and standard deviation of alpha t [alpha t = red/(red + green) fluorescence] were higher (.67 to .90) than any classically measured semen variables, suggesting that SCSA results within an individual were more consistent than other measures. Furthermore, average within-donor CV of alpha t parameters expressed as a percent of any given individual's means was around 10%, which is significantly lower than those derived from common semen measures. The SCSA is an objective, technically sound, biologically stable, sensitive, and feasible measure of semen quality.
Detection of unmodelled anomalous behaviours via localized controllers for condition systems

A method for detecting anomalous behaviours is presented for plants represented as condition systems. An anomalous behaviour can be viewed as observed behaviour of a real system (i.e. a robot, manufacturing cell, etc.) that cannot be accounted for by the set of plant models representing the system, even allowing for fault events. This work builds upon previous modular control synthesis techniques for condition systems.
Effects of loud and amplified speech on sentence and word intelligibility in Parkinson disease.

Purpose In the two experiments in this study, the author examined the effects of increased vocal effort (loud speech) and amplification on sentence and word intelligibility in speakers with Parkins...
Myasthenic Ptosis With Synkinetic Override in a Child With Congenital Oculomotor Nerve Palsy

Congenital myasthenia gravis usually involves the ocular motor system in predictable ways. The purpose of this report is to describe a child who had a congenital oculomotor nerve palsy with aberrant regeneration and fatigable ptosis associated with congenital myasthenia gravis. During periods of levator fatigability, gaze activation of the ipsilateral superior or medial rectus muscles produced instantaneous levator retraction with no fatigability. The ability of this child’s synkinetic neuromuscular connections to override her myasthenic levator fatigability may provide insight into the establishment of normal and abnormal neuromuscular connections in the setting of congenital myasthenia gravis.
Improving pregnancy drug warnings to promote patient comprehension.

Objective We sought to evaluate the effectiveness of a pharmaceutical labeling strategy intended to improve comprehension of a teratogen warning. Study design This is a secondary analysis that evaluated women of childbearing age who were assigned prescription containers with the current teratogen warning, a label with simplified text, or a label with simplified text and icons. The association between label type and understanding of label instructions was assessed. Results A total of 132 women were interviewed. Comprehension of the icon label (94%) was higher than for the standard and enhanced text-only labels (76% and 79%), respectively ( P Conclusion In our study, a teratogen warning label that had easy-to-read messages with icons significantly improved comprehension.
Welcome to Metals––a New Open Access Journal for a Growing Scientific Community

As I assume the role of Editor-in-Chief of this new journal, I look forward to serving in contributing to the advance of science and engineering in the field of metallic materials. This formidable task is made possible thanks to the excellent support of the Publisher and of the Editorial Staff of MDPI, as well as to a highly qualified Editorial Board. Hence, it is with pleasure that I accept this challenge, and I look forward to work with all of you in expanding the field of metals through journal contributions of current importance and of great interest to the scientific community. [...]
Personality and Credit Card Misuse Among College Students: The Mediating Role of Impulsiveness

Credit card misuse has negative long-term consequences for marketers. The study investigates the role that personality plays in students' credit card misuse. Mowen's 3M hierarchical model of personality is applied to survey data from 254 college students; and four elemental personality traits—emotional instability, introversion, materialism, and the need for arousal—are found to be positively associated with credit card misuse. Impulsiveness emerges as a significant central trait that mediates these effects. Insights generated from the present study have important managerial implications for the development of programs that better serve the needs of college student credit card users.
Effect of Inoculum Concentration and Calcium Salts on Infection of Apple Fruit by Botryosphaeria dothidea.

ABSTRACT The objective of this study was to determine the effects of calcium salts on growth of Botryosphaeria dothidea and incidence of white rot. The relative virulence of five B. dothidea isolates was determined using the apple cultivars Fuji, Gala, Golden Delicious, Liberty, and York. Cultivar and isolate differences in lesion diameter were significant. Cultivar differences occurred between Fuji, which was most susceptible, and Gala, which was least susceptible. Isolates PA-1 and PA-2 were most virulent. Isolate PA-4 was used at conidia concentrations of 1 × 104, 1 × 105, 1 × 106, and 1 × 107 conidia per ml on Golden Delicious fruit to test the effects of four inoculum concentrations on fruit infection by B. dothidea. Incidence of infection on detached, nonwounded fruit increased as inoculum concentration increased. The effects of four calcium salts on infection of wounded fruit by conidia were examined in field and laboratory experiments. In the field experiments, lesion size was slightly reduced on ...
Simulation Based Optimal Tolerancing for Multibody Systems

This paper introduces a new methodology for probabilistic optimal design of multibody systems. Specifically, the effects of dimensional uncertainties on the behavior of a system are considered. The proposed reliability-based optimization method addresses difficulties such as high computational effort and non-smoothness of the system’s responses, for example, as a result of contact events. The approach is based on decomposition of the design space into regions, corresponding to either acceptable or non-acceptable system performance. The boundaries of these regions are defined using Support Vector Machines (SVMs), which are explicit in terms of the design parameters. A SVM can be trained based on a limited number of samples, obtained from a design of experiments, and allows a very efficient estimation of probability of failure, even when Monte Carlo Simulation (MCS) is used. A modularly structured tolerance analysis scheme for automatic estimation of system production cost and probability of system failure is presented. In this scheme, detection of failure is based on multibody system simulation, yielding high computational demand. A SVM-based replication of the failure detection process is derived, which ultimately allows for automatic optimization of tolerance assignments. A simple multibody system, whose performance usually shows high tolerance sensitivity, is chosen as an exemplary system for illustration of the proposed approach. The system is optimally designed for minimum manufacturing cost while satisfying a target performance level with a given probability.Copyright © 2007 by ASME
Does America spend enough on addiction treatment? Results from public opinion surveys

Addiction treatment is often misunderstood and underappreciated in the United States. Although a large body of literature clearly demonstrates the clinical and economic benefits of addiction treatment for many clients and in most settings, the general public has a somewhat ambivalent attitude toward treatment expansion and taxpayer financing. A potential reason for this disconnect between economic evidence and public opinion is a weak identification with the need for, or the success of, addiction treatment for those individuals without a substance abuse problem themselves or in members of their family. Alternatively, addiction treatment stakeholders may be delivering an ineffective or misdirected message about the social value of this industry. This article explores these and other potential explanations for the paradoxically low placement of the addiction treatment industry among other socially important institutions in the United States. Although none of the explanations advanced in this article has been scientifically tested or verified, it is hoped that the historical inquiry and information provided herein will offer practical strategies for the stability and growth of the addiction treatment industry.
Effects of the dopamine reuptake inhibitor PTT on reinstatement and on food- and cocaine-maintained responding in rhesus monkeys.

High-affinity, slow-onset, long-acting dopamine transporter (DAT) inhibitors are being considered as potential agonist replacement therapies for cocaine addiction, and therefore the ability of these drugs to reinstate cocaine seeking and to selectively decrease cocaine-maintained responding should be assessed. The purpose of these experiments was to evaluate the effects of the active enantiomer of a high-affinity, slow-onset, long-acting DAT inhibitor, (−)2β-propanoyl-3β-(4-tolyl)-tropane (PTT), and cocaine on food- and cocaine-maintained responding and on extinguished responding previously maintained by cocaine in non-human primates using a within-subjects design. Rhesus monkeys (n=3) responded under a multiple fixed-ratio schedule of food (1 g) and drug reinforcement, and cocaine dose-response curves (saline, 0.003–0.3 mg/kg per injection) were determined. The effects of pretreatment with (−)PTT (0.001–0.056 mg/kg, IV) and cocaine (0.03–0.3 mg/kg, IV) were determined when the dose of cocaine that maintained peak response rates (0.03 mg/kg per injection) or saline was available. (−)PTT and cocaine reduced cocaine intake; (−)PTT affected cocaine self-administration only at doses that also decreased food-maintained responding. (−)PTT and cocaine reinstated responding that was previously reinforced by cocaine at lower doses than were necessary to decrease cocaine-maintained responding. For all studies, PTT was at least 1.0 log-unit more potent than cocaine. Compared to cocaine, PTT had a longer duration of action in all behavioral measures. These results suggest that PTT would decrease cocaine use, but only at doses that disrupted other behaviors. It appears that the potency of this class of drugs to reinstate cocaine-seeking is substantially greater than their potency at decreasing cocaine self-administration.
The coherence of memories for trauma: evidence from posttraumatic stress disorder.

Participants with posttraumatic stress disorder (PTSD) and participants with a trauma but without PTSD wrote narratives of their trauma and, for comparison, of the most-important and the happiest events that occurred within a year of their trauma. They then rated these three events on coherence. Based on participants’ self-ratings and on naive-observer scorings of the participants’ narratives, memories of traumas were not more incoherent than the comparison memories in participants in general or in participants with PTSD. This study comprehensively assesses narrative coherence using a full two (PTSD or not) by two (traumatic event or not) design. The results are counter to most prevalent theoretical views of memory for trauma.
Survival signaling in HoxA9/Meis1 AML

[Comment on Morgado et al, page 4020, and][1][Comment on Jin et al, page 3998][2]Two papers in this issue of Blood address the importance of survival signals in the expansion of myeloid leukemia progenitors in vivo. Morgado and colleagues report the surprising result that FLT3 signaling is
Subtyping specific reading disabilities: Classification approaches, recent advances, and current status

This article provides an overview of the literature on the subtyping of specific reading disabilities. The foundation for such subtyping is presented, with particular emphasis on how the rationale for a multidimensional conceptualization of reading problems evolved. Two broad-band classification approaches are described and several illustrative reading subtyping efforts are highlighted. The current status of reading disability subtyping efforts is described, underscoring recent research findings relative to dyslexia and subtyping. In addition, discussion focuses on continuing dilemmas facing clinicians and researchers working from a multidimensional conceptualization of reading disabilities. I conclude by addressing progress toward attaining an operational reading disability classification system. © 1996 Wiley-Liss, Inc.
Recent Work on Fast Photomultipliers Utilizing GaP(Cs) Dynodes

There exists an increasing demand for photomultipliers with better time resolution, higher count rate capabilities and generally faster time response. This paper discusses fundamental electron-optical considerations which determine the speed of response of electrostatically-focussed photomultipliers. The nature of time broadening is discussed with regard to geometrical and initial velocity effects at dynode surfaces. Time limitations inherent in the dynode material itself are also treated. Examples of different fast photomultiplier structures are given. A discussion of various delta-function light sources is included and the relative merits of these sources with respect to time performance, ease of use and cost is reviewed.
Spectrophotometric determination of de novo hemozoin/β-hematin formation in an in vitro assay

Formation of hemozoin in the malaria parasite, due to its unique nature, is an attractive molecular target. Several laboratories have been trying to unravel the molecular mechanism of hemozoin biosynthesis within the parasite digestive vacuoles. Use of different assay protocols for in vitro beta-hematin (synthetic identical to hemozoin) formation by these laboratories has led to inconsistent and often contradictory findings. Much of the difficulty may be attributed to oligomeric heme aggregates, which may be indistinguishable in some detection approaches if adequate separation of beta-hemtin is not achieved. Therefore, there is an urgent need for a widely accepted protocol for in vitro beta-hematin formation. We describe here a spectrophotometric assay for in vitro beta-hematin formation. The assay has been validated with the Plasmodium falciparum lysate, the parasite lipid extracts, and some commercially available fatty acids, which are known to initiate/catalyze beta-hematin formation in vitro. The necessity for multiple wash steps for accurate quantification of de novo hemozoin/beta-hematin formation was verified experimentally. It was necessary to wash the pellet, which contains beta-hematin and heme aggregates, sequentially with Tris/SDS buffer and alkaline bicarbonate solution for complete removal of monomeric heme and heme aggregates and accurate quantification of beta-hematin formed during the assay. The pellets and side products in the supernatant were characterized by infrared spectroscopy. No beta-hematin formation occurred in the absence of a catalytic/initiating factor. Based on these findings, a filtration-based assay that uses 96-well microplates, and which has important application in in vitro screening and identification of novel inhibitors of hemozoin formation as potential blood schizontocidal antimalarials, has been developed.
Childhood diabetes, insulin, and Africa

Mortality associated with Type 1 (insulin-dependent) diabetes has perceptually declined with the identification and widespread use of insulin. In the pre-insulin era, over 80% of all individuals developing diabetes died each year, now less than one in two hundred die. Sadly, this remarkable achievement has not reached the children who develop diabetes in sub-Saharan Africa where the onset of childhood diabetes is the equivalent of a death sentence. Two major issues of importance related to Type 1 diabetes in African and other developing countries are missed diagnosis and unavailability of insulin, issues which cannot be ignored.
High stability configuration for an acoustooptic heterodyne rf spectrum analyzer using slow shear TeO 2

A triangular, common-path interferometric rf spectrum analyzer arrangement has been demonstrated which has the property of high immunity to ambient vibration. Calculations show the TCPI arrangement, with two counter-propagating laser beams, is highly angle compensated and alignment stable when components are disturbed in position or orientation. Proper light polarization and Bragg cell geometry allows one Bragg cell to diffract primarily the clockwise beam and the other Bragg cell the counterclockwise beam. A birefringent quartz wedge shifts the heterodyne signal to a nonzero IF carrier frequency. Measured ambient phase noise is less than two degrees and calculated values indicate that further improvement may be possible.
Using GIS to identify under-represented ecosystems in the National Wilderness Preservation System in the USA

Wilderness designation continues to be a contentious effort and must be fully justified even in wealthy countries such as the USA. An important consideration in setting priorities for additional designations of Wilderness is to ensure that under-represented ecosystems are protected. The utility of Geographic Information Systems in performing this task is illustrated using data on ecoregions and areas in the National Wilderness Preservation System to determine the relative protection currently afforded to different ecoregions in the continental USA. We find that 23 of the 35 ecoregions have less than 1% of their land area protected as Wilderness, and 7 of the 35 have no land protected as Wilderness whatsoever. While much of the land with little protection is in areas dominated by private land ownership in the mid-west and southeast, a surprisingly large amount of land in the Intermountain states of Nevada and Utah, which is in public ownership, is substantially under-represented in the National Wilderness Preservation System as well. The implications of this analysis for wilderness allocation strategies are detailed. The technique illustrated in this paper is a useful aid in designing protected area strategies in countries throughout the world.
Determination of Parabens in Pharmaceutical Formulations by Solid-Phase Microextraction-Ion Mobility Spectrometry

Solid-phase microextraction (SPME) coupled with ion mobility spectrometry (IMS) was used for the detection and quantitation of 4-hydroxybenzoate preservatives, methylparaben, ethylparaben, propylparaben, and butylparaben, in commercial pharmaceutical products. For the first time, SPME-IMS is described for the simultaneous detection, separation, and quantitation of multiple analytes in complex matrixes. The parabens are extracted from the samples using SPME, and the analytes on the fiber are heated by the IMS desorber unit and vaporized into the drift tube. The four preservatives differing only by a methyl group were separated in less than 18 ms. The analytical procedure was optimized for fiber coating selection, extraction time, sample pH, sample volume, ionic strength, and IMS conditions. Separation characteristics such as resolution, theoretical plates, and drift times of the parabens were also evaluated based on the direct interfacing of SPME to IMS. The conditions were tested using six over-the-counte...
STEADY STATE MAINTENANCE OF ELECTROLYTES IN THE SPINAL CORD OF THE FROG

Isolated frog spinal cords equilibrated from 3 to 24 h in Ringer's solution maintained steady state conditions with regard to electrolyte composition. Total sodium and chloride contents measured on the same spinal cords were found to be nearly equivalent (Na = 46.6 ± 1.4μmol/g wet wt vs Cl = 46.2 ± 1.2μmol/g wet wt). Calcium and magnesium contents were 3.0 ± 0.5 and 4.8 ± 0.2pμol/g wet wt respectively for fresh spinal cords and 2.1 ± 0.4 and 5.5 ± 0.9pmol/g wet wt respectively for spinal cords equilibrated for 24 h. Zinc content was 0.29 ± 0.01 μmol/g wet wt. Insulin space was found to be smaller than sucrose space (0.24 ml/g vs 0.37 ml/g). Sodium and chloride spaces were slightly higher than sucrose space. Sodium and chloride in the non-sucrose space was 4.8 and 9.5 μmol/g wet wt. Residual radioactive sodium, or sodium content of spinal cords washed out for 180 min in non-radioactive Ringer's solution or in choline or lithium Ringer's solution, was 4.2 ± 0.4μmol/g wet wt (n = 9). The agreement between residual sodium content and sodium in the non-sucrose space suggests that the mean intracellular sodium content of the spinal cord neurons is low.
Ventricular tachycardia: mechanistic insights derived from adenosine.

A foundational concept in cardiac electrophysiology is that understanding the cellular mechanism of an arrhythmia provides essential insight for developing targeted therapeutic options. However, current clinical understanding of arrhythmogenic mechanisms other than re-entry is rudimentary, and the means by which to diagnose and differentiate these mechanisms are poorly defined. Grouping these mechanistic subtypes into broad and nonspecific categories, for example, non–re-entry or focal, further underscores our incomplete understanding of these arrhythmias. As the field of cardiac electrophysiology, like the rest of medicine, evolves toward the delivery of cell-based therapies, the need for a deeper understanding of clinical arrhythmia mechanisms and their arrhythmogenic cell lineages is apparent. One major difference between re-entrant and non– re-entrant ventricular tachycardia (VT) is that the electrophysiological substrate for re-entry is acquired during postnatal development and is due to anatomic insult (eg, ischemic heart disease or viral myocarditis), whereas the substrate for triggered activity is likely often acquired during embryological development, occurring independent of anatomic injury or structural heart disease.1,2 These dichotomous electrophysiological substrates, re-entry and non–re-entry, require tailored approaches to confirm diagnosis. In this review, we will elaborate on the development of a methodological approach for diagnosing non–re-entrant VT, which centers on the unique mechanism-specific properties of adenosine. This approach differs substantively from standard laboratory pacing methodologies used to validate the diagnosis of re-entrant arrhythmias and which are founded on the principles of entrainment.3 Adenosine is an endogenous nucleoside that exercises multiple regulatory functions that affect impulse generation and conduction, autonomic function, contractility, coronary vasodilation, and O2 supply–demand balance.4 Adenosine is rapidly inactivated as it is taken up by the cell through simple diffusion or a nucleoside transport system and is then deaminated to inosine or phosphorylated to adenosine monophosphate.5 The plasma half-life of adenosine is <1.5 s. …
The Curiosity in Marketing Thinking

This article identifies the curiosity in marketing thinking and offers ways to teach for marketing thinking through an environment that fosters students’ curiosity. The significance of curiosity in its relationship with thinking is that when curiosity is absent, so is thinking. Challenges are discussed in recognizing the fragility of curiosity through an understanding of the factors that suppress it. Drawing on existing research in education, psychology, and marketing, a synthesized pedagogical reversal is suggested—instead of pursuing learning in the form of students’ acquisition of knowledge, the focus should be on students’ exploration and appropriation of knowledge and marketing knowledge through their curiosity and thinking. The pedagogical differences are discussed in terms of expectations, measures of success, and what students leave with upon completion.
Genomic mapping and survival prediction in glioblastoma: Molecular subclassification strengthened by hemodynamic imaging biomarkers

Hemodynamic imaging biomarkers (relative cerebral blood volume [rCBV] measures) did not show any significant correlation with the various molecular subclasses by using the two most commonly accepted subclassification schema of glioblastoma but did provide important prognostic information independent of the molecular subclasses, and patients with higher rCBV showed worse prognosis and poor survival.
Photographing Navajos: John Collier Jr. On the Reservation

Photographing Navajos: John Collier Jr. On the Reservation, 1948-1953. C. Stewart Doty. Dale Sperry Mudge. and Herbert John Benally. Photographs by John Collier. Jr. Albuquerque: University of New Mexico Press. 2002. 224 pp. map. 98 halftones (97 are numbered).
Alignment sensitivity of holographic three-dimensional disks

We describe the rotational alignment sensitivity of three-dimensional holographic disks. It is shown that the reconstructed image always rotates by the angle by which the disk rotates; however, the center and the radius of rotation change as the recording geometry changes. A comparison among image plane, Fourier plane, and Fresnel holograms is given, and an optimum configuration (in terms of alignment sensitivity) in which the radius of rotation is zero is derived. We present experimental results and also discuss how the rotation alignment sensitivity affects the storage density and the readout–recording speed of the three-dimensional disk. A brief summary of other sources of misalignment is given.
A New Preclinical 3-Dimensional Agarose Colony Formation Assay

The evaluation of new drug treatments and combination treatments for gliomas and other cancers requires a robust means to interrogate wide dose ranges and varying times of drug exposure without stain-inactivation of the cells (colonies). To this end, we developed a 3-dimensional (3D) colony formation assay that makes use of GelCount technology, a new cell colony counter for gels and soft agars. We used U251MG, SNB19, and LNZ308 glioma cell lines and MiaPaCa pancreas adenocarcinoma and SW480 colon adenocarcinoma cell lines. Colonies were grown in a two-tiered agarose that had 0.7% agarose on the bottom and 0.3% agarose on top. We then studied the effects of DFMO, carboplatin, and SAHA over a 3-log dose range and over multiple days of drug exposure. Using GelCount we approximated the area under the curve (AUC) of colony volumes as the sum of colony volumes (microm2xOD) in each plate to calculate IC50 values. Adenocarcinoma colonies were recognized by GelCount scanning at 3-4 days, while it took 6-7 days to detect glioma colonies. The growth rate of MiaPaCa and SW480 cells was rapid, with 100 colonies counted in 5-6 days; glioma cells grew more slowly, with 100 colonies counted in 9-10 days. Reliable log dose versus AUC curves were observed for all drugs studied. In conclusion, the GelCount method that we describe is more quantitative than traditional colony assays and allows precise study of drug effects with respect to both dose and time of exposure using fewer culture plates.
Function of Sound Production by the Skunk Loach Botia horae (Pisces, Cobitidae)

In agonistic interactions with conspecifics, skunk loaches (Botia horae) typically exhibit lateral displays, attacks, and produce a sound (a “click”). Four experiments were conducted to determine the functional significance of the click sound. Behaviors of resident fish were monitored while characteristics of their shelter and the size or type of intruder fish introduced were varied. Manipulations in the four experiments involved: 1) the configuration of the available shelter; 2) the size or recent history of intruder fish; 3) playbacks of “click” sounds or aquarium noise; or 4) muting of resident fish. Lateral displays, attacks, and sounds produced by residents were monitored, and the responses of residents were analyzed in terms of the functional significance of “click” sounds to juvenile skunk loaches.