cssi/SciSciGPT-SciSciNet huggingface dataset:
Coagulation Factor Interaction with Platelets

Since the initial observation that bleeding is stopped by a platelet plug, it has been clear that platelets play an important role in hemostasis. Patients with very low platelet counts (thrombocytopenia) or with disfunctional platelets have a bleeding diathesis. With the further observation that the platelet plug becomes interwoven with fibrin, it has become clear that platelets interact with the coagulation proteins. In a review article in this issue of the journal, 1 Heemskerk et al. have summarized current information about the mechanisms by which platelets become activated. They have also examined current data on the interaction of coagulation factors with activated platelets. The purpose of this commentary is to highlight an area in which experts have differences of opinion: the question of whether platelets possess non-lipid binding proteins or receptors that bind procoagulant factors and coordinate assembly of the coagulation complexes. Heemskerk et al. have examined the mechanisms that lead to platelet activation with a particular emphasis on the changes that occur in phospholipid composition on the outer leaflet of the platelet membrane. The data cited in the review by Heemskerk et al. provides compelling evidence that changes in platelet membrane phospholipid composition are necessary for functional interaction of coagulation factors with platelets. The authors take the view that exposure of specific phospholipids on the outer leaflet of platelets is both necessary and sufficient to account for platelet procoagulant activity. To support this view, they cite work showing: that mutations of coagulation proteins which interfere with platelet binding also interfere with binding to phospholipid membranes; that blocking prothrombin binding to �
Systolic Blood Pressure Control and Mortality After Stroke in Hypertensive Patients

Background and Purpose—Hypertensive patients with electrocardiographic left ventricular hypertrophy are at increased risk of all-cause and cardiovascular death. Lowering blood pressure (BP) after stroke reduces the risk of recurrent stroke, but recent data suggest that lower systolic BP (SBP) measured 5 years after stroke is associated with increased mortality. Whether lower SBP is associated with increased short-term mortality after stroke in hypertensive patients is unclear. Methods—All-cause and cardiovascular mortality were examined in relation to average on-treatment SBP after stroke in 541 hypertensive patients with electrocardiographic left ventricular hypertrophy randomly assigned to losartan- or atenolol-based treatment who had new strokes during follow-up. Patients with on-treatment SBP 157 (highest tertile) were compared with patients with average SBP between 144 and 157. Results—During 2.02±1.65 years mean follow-up after incident stroke, 170 patients (31.4%)...
Autologous implantation of BMP2-expressing dermal fibroblasts to improve bone mineral density and architecture in rabbit long bones

Cell-mediated gene therapy may treat bone fragility disorders. Dermal fibroblasts (DFb) may be an alternative cell source to stem cells for orthopedic gene therapy because of their rapid cell yield and excellent plasticity with bone morphogenetic protein-2 (BMP2) gene transduction. Autologous DFb or BMP2-expressing autologous DFb were administered in twelve rabbits by two delivery routes; a transcortical intra-medullar infusion into tibiae and delayed intra-osseous injection into femoral drill defects. Both delivery methods of DFb-BMP2 resulted in a successful cell engraftment, increased bone volume, bone mineral density, improved trabecular bone microarchitecture, greater bone defect filling, external callus formation, and trabecular surface area, compared to non-transduced DFb or no cells. Cell engraftment within trabecular bone and bone marrow tissue was most efficiently achieved by intra-osseous injection of DFb-BMP2. Our results suggested that BMP2-expressing autologous DFb have enhanced efficiency of engraftment in target bones resulting in a measurable biologic response by the bone of improved bone mineral density and bone microarchitecture. These results support that autologous implantation of DFb-BMP2 warrants further study on animal models of bone fragility disorders, such as osteogenesis imperfecta and osteoporosis to potentially enhance bone quality, particularly along with other gene modification of these diseases. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1455–1465, 2015.
Bis(9H‐fluoren‐9‐ylmethyl) N,N‐bis(1‐methylethyl)phosphoramidate

[197709-11-8] C34H36NO2P (MW 521.63) InChI = 1S/C34H36NO2P/c1-23(2)35(24(3)4)38(36-21-33-29-17-9-5-13-25(29)26-14-6-10-18-30(26)33)37-22-34-31-19-11-7-15-27(31)28-16-8-12-20-32(28)34/h5-20,23-24,33-34H,21-22H2,1-4H3 InChIKey = KIEVTEOWWZWHEI-UHFFFAOYSA-N (reagent widely used for the conversion of alcohols into their corresponding difluorenylmethyl phosphates) Solubility: Soluble in dichloromethane, ethyl acetate, THF, and most organic solvents. Form Supplied in: pale-yellow oil. Preparative Method: N,N-diisopropylethylamine was added to an ice cooled solution of PCl3 in dry THF followed by the addition of diisopropylamine over 10 min. After the system had been stirred at 0 °C for an additional period of 1 h, another portion of N,N-diisopropylethylamine was added at 0 °C, followed by a solution of 9-fluorenylmethanol in dry THF. The reaction mixture was then stirred at room temperature for 24 h to produce the desired reagent (eq 1).1 (1) Handling, Storage, and Precautions: storage in a cool, dry, and ventilated place is recommended.
Stability of IIR digital filters constructed with the time-domain pipelining technique

Previously, z-domain or scattered lookahead pipelined IIR filters were thought to offer reduced computational complexity when compared to time-domain or clustered look-ahead IIR pipelined filters. However, the minimum-order augmentation technique provided improved computational complexity by minimizing superfluous poles, at the expense of increased transfer function denominator multipliers. In this paper, we show that for many realizations there exist stable time-domain pipelined IIR filters with computational complexity far less than the z-domain pipelined IIR filters. The decreased complexity in time-domain pipelined IIR filters results from the occurrence of "stability pockets" which allow stable pipeline IIR filters with far fewer superfluous poles than predicted by the stability analyses previously performed. >
Classroom note: The number c in Cauchy's average value theorem

The location of the number c arising from Cauchy's Average Value Theorem is described when the size of the interval is small.
Evoked Release of Norepinephrine and Serotonin from Brain Slices: Inhibition by Lithium

Slices of mammalian brain accumulate H 3 -norepinephrine and H 3 -serotonin when incubated in a physiologic medium containing these tritiated monoamines. When these tissues are subjected to mild electrical stimulation of short duration, which is associated with depolarization of nerve membranes, a striking increase in the rate of efflux of the exogenous labeled monoamines occurs. Stimulation-induced release of both labeled monoamines is diminished by the presence of lithium ions in the perfusing medium; related monovalent cations had no such effect. Evoked release from slices of brain from animals treated intraperitoneally with lithium chloride for 3 days was also reduced.
Comparative Evaluation of a New Disposable Rotating Membrane Oxygenator with Bubble Oxygenator

The comparative in vivo performance of adult-size bubble and rotating membrane oxygenators was evaluated during closed-chest cardiopulmonary bypass for six hours in two groups of dogs. The results show that the rotating membrane oxygenator is efficient in oxygen and carbon dioxide transfer with minimal trauma to blood, while platelet destruction and hemolysis were marked with the bubble oxygenator. Cerebral, cardiac, and respiratory complications were frequent with the bubble oxygenator and absent with the membrane oxygenator.
A LOOK AT THE REENTRY PROBLEM

Reentry guidance and control in near-earth orbits and near escape velocity as well as in deep space and at velocities in excess of escape velocity
Expression of the sorghum 10-member kafirin gene cluster in maize endosperm

Functional analysis of chromosomal segments containing linked genes requires the insertion of contiguous genomic sequences from bacterial artificial chromosomes (BACs) into the genome. Therefore, we introduced a 90-kb large BAC clone carrying a 10-copy tandem array of kafirin storage protein genes from sorghum linkage group J, mixed with a selectable marker gene, directly into maize cells using the particle bombardment method. Transgenic plants were regenerated and seeds from eight different transgenic lines were produced. One such transgenic plant was selected that had the entire kafirin gene cluster on a single continuous DNA fragment spanning more than 45 kb integrated into its genome. When alcohol-soluble proteins from individual T2 and T3 seeds of this event were analyzed, significant levels of kafirin were found in addition to the endogenous zein storage proteins, demonstrating that the large exogenous DNA segment is stably integrated into the maize genome and expressed at high levels in subsequent generations. Therefore, we could provide a new utility of plant transformation by the particle bombardment method for functional genomics of multigene families and the modification of the nutritive quality of cereal grains. Despite a tandem array of highly homologous sequences at the transgenic locus, no gene silencing was observed, probably owing to the effects of co-transformed flanking sequences. The expression studies of the transgenic locus also revealed new features of storage protein gene promoters that differed from previous transient gene expression studies, thereby illustrating the significance of the concentration and configuration of DNA–protein interactions in the regulation of gene expression.
Come out, Come out: Frameline Films' Holiday Havoc.

Five Frameline short films by and about LGBT youth's coming-out narratives are reviewed by a professor and his (under)graduate university students studying visual culture and the socio/cinematic construction of (homo)sexualities. Respondents collectively found the group of films moving and well suited for viewing by middle- and high-school-age students.
Congenital diaphragmatic hernia

Congenital diaphragmatic hernia occurs in approximately 1 in every 2500 live births and is associated with a reported mortality of almost 35% in live-born patients and a higher mortality when in utero deaths are counted. Ventilator-induced lung injury, pulmonary hypoplasia, and other associated anomalies account for the high death rate. Numerous adjunctive measures have been used to treat these patients. Inhaled vasodilators (nitric oxide), intravenous vasodilators, and fetal therapy have no proven benefit. While animal models of congenital diaphragmatic hernia are surfactant deficient, controversy remains over the use of surfactant in infants. There has been no clinical trial showing any clear benefit with the use of exogenous surfactant in these patients. Similarly, prenatal corticosteroids show some improvements in animal models, but again, there is a complete absence of supportive data to show benefit in humans. Mechanical ventilator strategies that limit ventilator-induced lung injury by avoiding hyperventilation and lung over inflation are the strategies currently in use that have been associated with improved survival. Long-term follow-up of these patients is quite important since gastroesophageal reflux, developmental delay, chronic lung disease, and chest wall deformity are all seen with increased frequency in these children.
Inclusion of Children with Special Needs in School-Age Child Care Programs.

From an ecological perspective, the inclusion of children in school-age child care (SACC) requires collaboration among policy makers, educators, parents, and child care providers. Both typically and atypically developing children benefit from inclusive programs, yet they pose challenges for care-givers primarily due to lack of training, resources, and identification of successful inclusive program components. The process of successful SACC inclusion should be at the forefront of human service and research agendas.
Evaluation of Wheat Polyphenol Oxidase Genes

ABSTRACT Polyphenol oxidases (PPOs) present in mature wheat (Triticum aestivum L.) kernels have been implicated in the undesirable darkening of cereal products such as Asian noodles. To accelerate the functional characterization of wheat PPOs and allow the identification of those PPO genes that are primarily involved in food biochemistry, several basic local alignment search tool (BLAST) searches of expressed sequence tag (EST) databases were performed using a known wheat PPO sequence as a search argument; identified ESTs were resequenced and aligned. Results from this study suggest the presence of at least six PPO genes in hexaploid wheat, falling into two clusters with three similar sequences each. Based on the tissues used for cDNA library preparation, three genes (all members of one cluster) are expressed during kernel development and may therefore influence cereal product quality; the remaining three genes (belonging to the second cluster) were isolated from nonkernel cDNA libraries and may not be ex...
Cross-over trial comparing maternal acceptance of two fetal movement charts.

Objective: To compare two daily fetal movement charting techniques to determine which chart was preferred by patients and which promoted more patient adherence. Methods: This randomized trial included patients with singleton gestations between 28 and 34 weeks' gestation, with intact membranes and not in labor. Consenting women were given a Hollister® chart and a 'count to 10' chart in a cross-over manner over two consecutive 1-week periods. Each patient answered a questionnaire establishing which chart was preferred. All returned charts were evaluated for patient adherence. Data were analyzed using either the Yates-corrected χ2 test or Fisher's exact test when appropriate. Results: Forty patients agreed to participate, and 31 completed and returned both charts. The 'count to 10' chart was clearly preferred over the Hollister chart (29 vs. 2; p = 0.002) because of the shorter recording period (median 23 min vs. 1 h; p < 0.01). The proportion of patients who fully completed the 'count to 10' chart during th...
Penalized Likelihood Phenotyping: Unifying Voxelwise Analyses and Multi-Voxel Pattern Analyses in Neuroimaging Penalized Likelihood Phenotyping

Neuroimage phenotyping for psychiatric and neurological disorders is performed using voxelwise analyses also known as voxel based analyses or morphometry (VBM). A typical voxelwise analysis treats measurements at each voxel (e.g. fractional anisotropy, gray matter probability) as outcome measures to study the effects of possible explanatory variables (e.g. age, group) in a linear regression setting. Furthermore, each voxel is treated independently until the stage of correction for multiple comparisons. Recently, multi-voxel pattern analyses (MVPA), such as classification, have arisen as an alternative to VBM. The main advantage of MVPA over VBM is that the former employ multivariate methods which can account for interactions among voxels in identifying significant patterns. They also provide ways for computer-aided diagnosis and prognosis at individual subject level. However, compared to VBM, the results of MVPA are often more difficult to interpret and prone to arbitrary conclusions. In this paper, first we use penalized likelihood modeling to provide a unified framework for understanding both VBM and MVPA. We then utilize statistical learning theory to provide practical methods for interpreting the results of MVPA beyond commonly used performance metrics, such as leave-one-out-cross validation accuracy and area under the receiver operating characteristic (ROC) curve. Additionally, we demonstrate that there are challenges in MVPA when trying to obtain image phenotyping information in the form of statistical parametric maps (SPMs), which are commonly obtained from VBM, and provide a bootstrap strategy as a potential solution for generating SPMs using MVPA. This technique also allows us to maximize the use of available training data. We illustrate the empirical performance of the proposed framework using two different neuroimaging studies that pose different levels of challenge for classification using MVPA.
Nurture net of nature: Re-evaluating the role of shared environments in academic achievement and verbal intelligence.

Prominent authors in the behavioral genetics tradition have long argued that shared environments do not meaningfully shape intelligence and academic achievement. However, we argue that these conclusions are erroneous due to large violations of the additivity assumption underlying behavioral genetics methods – that sources of genetic and shared and nonshared environmental variance are independent and non-interactive. This is compounded in some cases by the theoretical equation of the effective and objective environments, where the former is defined by whether siblings are made more or less similar, and the latter by whether siblings are equally subject to the environmental characteristic in question. Using monozygotic twin fixed effects models, which compare outcomes among genetically identical pairs, we show that many characteristics of objectively shared environments significantly moderate the effects of nonshared environments on adolescent academic achievement and verbal intelligence, violating the additivity assumption of behavioral genetic methods. Importantly, these effects would be categorized as nonshared environmental influences in standard twin models despite their roots in shared environments. These findings should encourage caution among those who claim that the frequently trivial variance attributed to shared environments in behavioral genetic models means that families, schools, and neighborhoods do not meaningfully influence these outcomes.
Biological oxidation of arsenite in seawater.

The biological mediation of arsenic speciation has been shown to include oxidation, reduction, methylation and demethylation mechanisms. This study examines the biological oxidation of arsenite in seawater at low levels (100 parts 10 −9 , 1·3 μ m ). Experimental results indicate that abiotic oxidation proceeds at a slow, constant rate, as can be predicted from a consideration of physical and chemical variables only. In the presence of certain aquatic bacteria, however, oxidation is rapid, and the As(III) concentration decreases exponentially with time. Aspects of bacterial oxidation which are investigated include qualitative characteristics of the organisms, enzyme-substrate relationships and kinetic considerations in relation to chemical, physical and biological variables. The distribution of this phenomenon in natural waters is evaluated, and the importance of bacterial oxidation assessed relative to an overall arsenic budget. Results of this study are compared to those of previous investigations of bacterial arsenite oxidation.
3D echo planar imaging: application to the human head

In this work, the authors present 3D images acquired from the human head using echo planar encoding for two of the three dimensions of k-space. The third dimension of k-space is filled by selecting and phase encoding a slab of spins as in conventional 3D steady state (GRASS based) acquisition regimens. Using this approach, a 128 x 64 x 64 3D data matrix could be obtained in 3.4-4.7 sec using effective TE values of 24 and 34 ms, respectively. High quality 3D images could be acquired once phase ghosts present on 2D images were minimized through proper adjustments of scanner hardware.
Interferograms of Window Wavefront Deformations as a Measure of Angular Deviations to a Line of Sight

An interferogram of the wavefront deformation to a flat wave caused by an aircraft or spacecraft window contains all the error contribution effects of the window. The interferogram may be analyzed to determine the slope of this wavefront at a given point, which yields the angular deviation to a line of sight through the point. The interferogram as used in this study is a two-dimensional photo representing the three-dimensional relationship of the transmitted wave relative to the flat reference wave. The progression from light to dark fringes is the progression of the third dimension normal to the photo, and the fringes are thus similar to contour lines on a topographic map. To demonstrate the ability to obtain interferograms, to analyze interferograms, and to achieve sufficient accuracy, an aircraft window and spacecraft window were studied in an experimental test. The deviations to a line of sight were derived from transmitted wave interferograms obtained in the laboratory and were also measured precisely by an autocollimator system. The standard deviation of the transmitted wave deviations derived from interferograms relative to directly measured deviations was 0.7 sec of arc, indicating that the transmitted wave interferogram method is a good tool for window error determination.
Evaluation of the ‘blanket’ algorithm for ruggedness assessment

Abstract A Richardson plot of an arbitrarily rugged line can be constructed by ‘coating’ it with a ‘blanket’ of increasing thickness and calculating its length from the blanket's area divided by its thickness. This algorithm was applied to lines constructed with constant and variable random frequency and random amplitude within a predetermined range. Since lines could be generated using the same parameters but different random features, the method could be tested for reproducibility and sensitivity. It is demonstrated that the method satisfies both conditions, and is therefore a convenient way to assess ruggedness.
Chronic dosing of phosphodiesterase type 5 inhibitors

Ten years ago, the introduction of sildenafil citrate for the treatment of erectile dysfunction fundamentally changed the field of sexual medicine. The sexual indications, along with the pharmacologic characteristics of this drug, led to its approval for on-demand use. Additional phosphodiesterase type 5 (PDE5) inhibitors were introduced for the treatment of erectile dysfunction, and each subsequent agent used the on-demand treatment paradigm. Yet, advances in laboratory investigations and accumulating clinical evidence suggest that daily dosing is feasible and may improve treatment efficacy and compliance. Recently one of these agents, tadalafil, was approved in several countries for once-daily dosing. Broad clinical experience with this treatment option is just beginning. The widespread presence of PDE5 in other vascular beds has led to additional nonsexual indications for PDE5 inhibitors.
Separation of the Iris Pigment Epithelium

Surgical repair of traumatic corneal and scleral lacerations with uveal prolapse postoperatively disclosed a separation of the pigment epithelium. Posterior synechiae and a dense occlusion of the pupil tightly bound the papillary margin to the lens capsule. Traumatic, surgical, and mydriatic agents tore the anterior pigment epithelium layer loose from the adherent pupillary margin and induced a complete separation of the iris along the original lumen of the embryonic cup, between the two epithelial layers. Once the consolidated fibrin cleared, the posterior pigment layer retraccted from the visual axis but did not reattach to the iris.
A pulse-train generator for biological stimulation.

A circuit to generate periodically a series of rectangular pulses, or ‘train’, for biological stimulation is described. Analogue integrators are used to determine pulse duration, spacing, and train length from 0·05 to 5000 ms. The 0·10 V output may be used directly or to adapt conventional stimulators for train production. General-purpose integrated-circuit amplifiers, gates, and bistables are used to facilitate circuit construction and duplication.
Bosques andinos del sur de Ecuador, clasificación, regeneración y uso

Existen muy pocos inventarios y descripciones sintaxonomicas de la vegetacion de bosques montanos tropicales. Este trabajo presenta datos sobre los bosques del sur de Ecuador localizados en la Reserva Biologica San Francisco, limite norte del Parque Nacional Podocarpus. Se propone la siguiente clasificacion junto con notas sobre los factores edaficos que contribuyen a su establecimiento. El «Bosque Montano Bajo» (1800-2150 m), formando el orden Alzateetalia verticillatae, muestra 2-3 estratos arboreos muy diversos, con arboles de 20-35 m de altura, y es una climax mosaico tipico. Creciendo sobre Terric Haplosaprists y Aquic Dystrupepts, originado del material de derrumbes viejos, este tipo de bosque se extiende hasta los 2300 m sobre el nivel del mar en quebradas protegidas de viento. A altitudes de 2100-2650 m (menos de 2750 m) la estructura del bosque y la composicion floristica cambia totalmente. Esta vegetacion, el «Bosque Montano Alto» forma el orden de Purdiaeaetalia nutantis y crece sobre Histic Petraquepts. Representando una vegetacion monotipica con un solo estrato arboreo de 5-10 m (?15 m) de altura, completamente dominado por Purdiaea nutans (Cyrillaceae). El bosque ubicado a mayor altitud en el area, densamente enlazado con el paramo es el «Bosque Nublado Subalpino». Descritos como Clusio ellipticae-Weinmannietum cochensis aparecen mas como una vegetacion arbustiva casi impenetrable, y crecen sobre Humaquic Epiaquents. El limite del bosque es causado principalmente por los vientos fuertes de la region. Derrumbes e incendios naturales representan el «motor» de regeneracion de los bosques. Se encontro carbon en la base de los niveles A de muchos perfiles de suelo. El analisis 14C preciso una edad de 710-980 ±50 anos antes del presente. Esto indica que fuegos en la vegetacion han contribuido a la dinamica de esta vegetacion en el pasado y no es un fenomeno reciente. El diametro basal de los arboles y el volumen total de madera por hectarea disminuyen rapidamente con la altitud a partir de los 2100 m y no pueden ser eficazmente utilizados para una explotacion de madera sostenible.
The effect of contour closure on shape perception.

We studied psychophysically whether 'contour closure' enhances the accuracy of shape perception. Stimulus configurations (presented on a blank background) always consisted of identical pattern elements, but the positions of the local elements were varied: the global contour shape either contained closure or not. In the first two stimulus conditions (Closure), the oriented pattern elements (Gabor patches) formed a 'closed' rectangular shape composed of either four long lines or four corners. In the third condition (No closure), the global shape was composed of the four corners, but they were outward oriented, and hence they did not form the outline of a closed contour. We measured the precision of shape perception using a discrimination task in which observers judged the aspect ratio of the outline shape i.e. whether the rectangular shape was tall or wide. We found that: (i) shape discrimination was better (more precise) for Closed contours than for Non-closed contours, i.e. the aspect ratio discrimination thresholds were lower for the Closed than Non-closed configurations. The improved performance could not be explained by differences in visibility of the local elements in the two conditions. (ii) For closed contours, shape discrimination was more precise when the local elements were aligned with the global shape, than when the local elements were orthogonal to it.
CtIP Links DNA Double-Strand Break Sensing to Resection

In response to DNA double-strand breaks (DSBs), cells sense the DNA lesions and then activate the protein kinase ATM. Subsequent DSB resection produces RPA-coated ssDNA that is essential for activation of the DNA damage checkpoint and DNA repair by homologous recombination (HR). However, the biochemical mechanism underlying the transition from DSB sensing to resection remains unclear. Using Xenopus egg extracts and human cells, we show that the tumor suppressor protein CtIP plays a critical role in this transition. We find that CtIP translocates to DSBs, a process dependent on the DSB sensor complex Mre11-Rad50-NBS1, the kinase activity of ATM, and a direct DNA-binding motif in CtIP, and then promotes DSB resection. Thus, CtIP facilitates the transition from DSB sensing to processing: it does so by binding to the DNA at DSBs after DSB sensing and ATM activation and then promoting DNA resection, leading to checkpoint activation and HR.
Occurrence and Nonoccurrence of Random Sequences: Comment on Hahn and Warren (2009)

On the basis of the statistical concept of waiting time and on computer simulations of the "probabilities of nonoccurrence" (p. 457) for random sequences, Hahn and Warren (2009) proposed that given people's experience of a finite data stream from the environment, the gambler's fallacy is not as gross an error as it might seem. We deal with two critical issues in Hahn and Warren's argument, a possible ambiguity in distinguishing the events of occurrence and nonoccurrence, and an incomplete consideration of the context in which the statistics of waiting time are defined. Our analyses show that the statistics of waiting time and the probabilities of nonoccurrence, once correctly interpreted, do not vindicate the error in the gambler's fallacy.
Radiation Exposure Dose Trends and Radiation Dose Reduction Strategies in Medical Imaging

Since the discovery of x-rays, many investigations of radiation effects on humans have taken place. From the discovery of severe x-ray dermatitis near the end of 1896, the multiple radiation burns endured by Thomas Edison's assistant, Clarence Dally, to the establishment of early radiation regulation in 1929, radiation exposure has been a continuing concern. Studies from the 1940s to the 1960s looked at effects such as leukemia and other cancers that appeared to be caused by exposure to radiation; outcomes of these studies resulted in increased regulation, establishment of dose tolerances and the development of the National Council on Radiation Protection (NCRP). Since the 1960s, similar studies have continued resulting in stricter dose limits. However, a recent resurgence of radiation exposure injuries led to this literature review that revealed a gap in the literature concerning the radiation practices and continued education of today's radiologic technologists. Through this review, recommendations for dose reduction strategies are included.
Who lives near coke plants and oil refineries An exploration of the environmental inequity hypothesis

Facility-specific information on pollution was obtained for 36 coke plants and 46 oil refineries in the United States and matched with information on populations surrounding these 82 facilities. These data were analyzed to determine whether environmental inequities were present, whether they were more economic or racial in nature, and whether the racial composition of nearby communities has changed significantly since plants began operations. The Census tracts near coke plants have a disproportionate share of poor and nonwhite residents. Multivariate analyses suggest that existing inequities are primarily economic in nature. The findings for oil refineries are not strongly supportive of the environmental inequity hypothesis. Rank ordering of facilities by race, poverty, and pollution produces limited (although not consistent) evidence that the more risky facilities tend to be operating in communities with above-median proportions of nonwhite residents (near coke plants) and Hispanic residents (near oil refineries). Over time, the racial makeup of many communities near facilities has changed significantly, particularly in the case of coke plants sited in the early 1900s. Further risk-oriented studies of multiple manufacturing facilities in various industrial sectors of the economy are recommended.
Evidence that the serological determinant of H–Y antigen is carbohydrate

The histocompatibility–Y (H–Y) antigen is a minor his to compatibility antigen which has been detected on cell surfaces from the heterogametic sexes of mammalian, bird, amphibian, teleost and invertebrate species1–3. H–Y is thought to be a male-determining substance in mammals because of its almost perfect correlation with maleness among a variety of mammalian species. To characterize the molecular determinant responsible for H–Y-specific serological activity, H–Y-positive immunoabsorbent cells were first subjected to various treatments which alter protein or carbohydrate structure and then tested for their ability to absorb H–Y antisera. We present here evidence that the serological determinant of H–Y antigen is carbohydrate.
RADIOLOGY IN MENDELSON'S SYNDROME

Four cases of Mendelson's syndrome (acid pulmonary aspiration) are presented. They all demonstrate an acute diffuse alveolar filling pattern. This appearance is by no means specific. However, in the absence of other causes for this pattern and of evidence of left ventricular failure the radiologist may alert the clinician to the correct diagnosis. Early recognition of this syndrome will result in prompt treatment which differs significantly from that of other causes of this radiographic appearance. The differential diagnosis is discussed.
Testing for Alzheimer's.

In his article “Allen Roses: From ‘street fighter’ to corporate insider” (News & Comment, 15 May, p. [1001][1]), Eliot Marshall notes (p. [1004][2]) that Roses disagreed with a group of experts at Stanford who had concluded that widespread molecular testing for late-onset Alzheimer's disease
Clinical auscultation skills in pediatric residents.

To the Editor — We read with great interest the article by Gaskin et al entitled “Auscultation Skills in Pediatric Residents,” published in Pediatrics. 1 Their article is an important contribution to a growing list of studies2,3,4,5,6 describing the suboptimal cardiac auscultation skills among internal medicine, family practice, and pediatric residents. Of additional concern was the small number of pediatric residents (6 of 47) in the Gaskin study who chose a cardiology elective. In an …
Electron beam effects on diethylsilane-covered Si(100) surfaces investigated by electron stimulated and temperature programmed desorption

The effect of low-energy electron irradiation on adsorbed layers of diethylsilane (DES) on the Si(100) surface at 100 K were studied using temperature programmed desorption (TPD) and electron stimulated desorption (ESD). As has been observed previously, TPD studies of adsorbed DES have shown desorption of both molecular hydrogen and ethylene. Adsorption of DES at 100 K also results in a loosely bound layer that desorbs molecularly at a temperature of ∼140 K. Strong evidence exists for thermal removal of ethylene from the surface during programmed heating via a β-hydride elimination process. Irradiation of the dosed surface with electrons results in a number of interesting effects. Electron-induced enhancement of both hydrogen and ethylene desorption from Si(100) is observed. In addition, both neutral and ionic desorption of surface species was observed, induced by electron irradiation. Desorption of neutral species having masses of 2, 15 and 28 indicate electron-induced removal of hydrogen and ethylene, with a methyl group appearing as a result of ethylene dissociation. Hydrogen removal occurs from two distinct states, as identified by the decay of neutral hydrogen from the surface, characterized by two decay constants. Analysis of the energy of desorbing H+ species suggests two distinct kinetic energy distributions at 1.8 and 4.1 eV, which contribute to the desorption signal. Copyright © 2003 John Wiley & Sons, Ltd.
Brownian motion, exit times and stochastic riemannian geometry

In this report we consider stochastic systems which are modelled by Brownian motion on a Riemannian manifold. Of special interest are the exit times from small geodesic balls. Our results may be viewed as quantitative refinements of the comparison theorems obtained by Debiard Gaveau-Mazet r31 which are of the followinq tvpe: Let M be a Riemannian manifold with sectional"' curvature K, bounded by a constant in the form K< k. It is then shown that the exit time from a-geodesic ball is less than the exit time from a geodesic ball of the same radius in the space of constant curvature k. However no information is available in case we only have hypotheses on, say, the scalar curvature. Therefore it is important to develop estimates for the exit time with no hypotheses on the metric or the curvature tensor of the manifold. In this report we give results on the first and second moments of the exit time of Brownian motion. These are used to give stochastic characterizations of Euclidean and rank one symmetric spaces. Much of the work is in collaboration with Alfred Gray, to whom go many thanks for helpful conversations.
Gender Differences in Risk Factors for Gonorrhea Among Alaskan Drug Users

SUMMARY This study developed separate models predicting risk for gonorrhea infection among female and male drug users in Anchorage Alaska. Data were collected with the Risk Behavior Assessment, a structured interview that was administered to 728 male and 321 female adult participants who were currently not in drug treatment. History of gonorrhea infection was self-reported and coded as ever or never. The risk factors for women are trading sex for money, being American Indian or Alaska Native, perceiving oneself as homeless, and trading sex for drugs. For men the risk factors are injecting or snorting cocaine, being Black, being older, acquiring illegal income excluding prostitution, and using amphetamines. Results are useful for guiding public health intervention and policy development in drug using populations in Alaska.
The effect of experimenter bias in a cola taste test

In a simulated cola taste test, experimenters' nonverbal behaviors influenced subjects' cola choices, although subjects expressed no awareness of the experimenters' impact. Nonverbal intimacy behaviors may make subjects feel comfortable in same-sex pairs and uncomfortable in mixed-sex pairs, resulting in an association of these internal states with cola preferences.
Obesity: stressing about unfolded proteins

Two reports in this issue identify a link between insulin action and the unfolded protein response—a pathway that helps the endoplasmic reticulum cope with cellular stress (pages 429–437 and 438–445). The results expand our understanding of the pathogenesis of insulin resistance and provide new targets for prevention and treatment of obesity.
Improving the interface between biomaterials and the blood. The gene therapy approach.

Synthetic grafts can substitute for diseased arteries and function well as long as there is high blood flow. In low-flow situations, they are prone to sudden thrombosis. They also provoke a wound-healing response from the adjacent vessels and the surrounding tissue that under some circumstances narrows the lumen and reduces blood flow.1 Despite 50 years of investigation and development, we still lack “smart biomaterials” that possess the properties characteristic of normal vessels needed for the regulation of coagulation and luminal diameter. What can we do to improve this situation? A great deal of effort has been put into making materials with nonthrombotic and nonanticoagulant surfaces. Although these materials are relatively inert in the short term, they are soon modified by the deposition of proteins from the blood, and they do not necessarily form smooth junctions with the adjacent arteries. One way to improve their performance is to encourage the formation of a surface on the biomaterial that mimics the surface of a normal vessel. Most investigators would consider a monolayer of endothelial cells as the right surface, even though other cell types (eg, vascular smooth muscle cells, mesothelial cells) and certain antithrombotic proteins might be able to form a suitable covering.2 3 4 If the endothelium is the right surface, then certain assumptions must be made. First, endothelium can be seeded onto the graft or induced to grow from local sources to form a confluent layer at the surface. Second, the endothelium over a …
Dimeric complexes containing the disulfidodiron(2+) cores coordinated by non-sulfur terminal ligands. Synthesis, structural characterization, and spectroscopic properties of [Et4N]2[Fe2S2(o,o'-C12H8O2)2], [Et4N]2[Fe2S2(C4H4N)4], and [Et4N]2[Fe2S2(O-o-C6H4CH(n-C4H9)NHC6H4-o-S)2] and the structure of [Ph4P]2[Fe2S2(OC6H4-p-CH3)4]

Le compose [(C 2 H 5 ) 4 N] 2 Fe 2 S 2 (O,O'-C 12 H 8 O 2 ) 2 ] cristallise dans le systeme monoclinique avec le groupe d'espace C2/c. Affinement de la structure jusqu'a 0,0325. Le compose [(C 2 H 5 ) 4 N] 2 Fe 2 S 2 (C 4 H 4 N) 4 ] cristallise avec le groupe d'espace P2 1 /n. Affinement de la structure jusqu'a 0,0689. Le compose [(Et) 4 N] 2 [Fe 2 S 2 (O-o-C 6 H 4 CH(n-(CH 2 ) 3 -CH 3 )-NHC 6 H 4 -o-S) 2 ] cristallise avec le groupe d'espace P2 1 /c. Affinement de la structure jusqu'a 0,0624. Le complexe [(C 6 H 5 ) 4 P] 2 [Fe 2 S 2 (OC 6 H 4 -p-CH 3 ) 4 ] cristallise avec le groupe d'espace P2 1 /a. Affinement de la structure jusqu'a 0,0621
Extraction of Chronically Implanted Cardiovascular Electronic Device Leads

Cardiovascular implantable electronic devices (CIED) are a remarkable success story. These systems are widely used to prevent symptomatic bradycardia, treat malignant tachyarrhythmia, and to restore a more physiologic contraction to a failing left ventricle. Implantation of a CIED usually involves a lifelong commitment to this therapy, which, unfortunately, is not free from complication requiring removal and/or replacement of all or part of the system. The major obstacle to removal of a CIED is the fibrous attachments that develop between a lead and co-existent leads, veins, and the heart. This process increases over time such that, by one year, removal by traction alone may be problematic and, if aggressive, result in complication. Physicians, surgeons, and engineers have refined techniques of percutaneous lead extraction and developed tools, which have facilitated the process, increased success, and lowered the incidence of complication. Extraction may be performed for a variety of indications some of which are unanimously agreed upon while others remain controversial. Proponents of a broadened application of extraction have proffered the concept of ‘lead management,’ which includes the removal of all leads that are not clinically relevant to the patient. The benefit of this approach would be to limit the risk of future complication, such as venous occlusion or thromboembolism, and to obviate the increase in difficulty of extraction (due to longer implant duration) that might accompany removal should that be required in the future. Intuitively appealing as this approach might be, there is little evidence supporting it, and the extraordinarily large number of patients currently implanted with recalled ICD leads is indicative of the potential impact this practice may have. This review will discuss extraction, its indications, and outcomes.
A comparison of the desorption of CO from Pt and Rh particles on α-Al2O3{0001}

Abstract The adsorption of CO on Rh particles supported on α-Al 2 O 3 {0001} was studied using temperature programmed desorption (TPD), and the results were compared to those obtained for Pt particles in a previous study [E.I. Altman and R.J. Gorte, Surface Sci. 172 (1986) 71]. The Rh was evaporated onto the nonporous α-Al 2 O 3 {0001} substrate in ultra-high vacuum, and metal coverages were measured using a quartz-crystal, film thickness monitor. Average particle sizes were calculated from adsorption uptakes, and the particle size was varied by changing the amount of metal deposited onto the substrate. Auger electron spectroscopy (AES) measurements indicated that Rh grew as three-dimensional particles on the alumina substrate at 300 K. For all Rh particle sizes studied, CO desorbed in peaks at 500 and 425 K, the same temperatures observed on Rh foils and single crystals. The relative proportion of CO in each desorption state was found to be only weakly dependent on particle size, in sharp contrast to the results observed on Pt. On Pt, the strong dependence of the TPD features with particle size was interpreted as being due to changes in the crystallographic orientation of the surface sites with particle size. Since the desorption of CO on Rh is much less sensitive to the crystallographic orientation of the surface than it is on Pt, the fact that desorption is also much less sensitive to particle size supports the conclusion that changes in the TPD curves with particle size on both Rh and Pt are due to changes in the crystallographic orientation of the sites on the small particles.
Clinical and research advancements in cast-gold restorations.

Abstract This report discusses some of the recent advances in cast-gold dental treatment. Cast-gold restorations serve many essential purposes which other restorative materials cannot serve at this time. The presently available laboratory materials permit some laboratory phases of the treatment procedures to be satisafctorily performed by a laboratory technician.
Sequentially encoded data structures that support bidirectional scanning

A coding method and apparatus that supports bidirectional scanning is disclosed for sequences of fields of variable length and/or type. Symmetric difference separators of the two immediately adjacent data field types are generated by exclusive-OR addition and utilized as punctuation marks to support bidirectional scanning. Parity checking techniques and hardware are utilized to resolve boundary alignment problems when a separator is in error. An extension of the concept of the invention to hierarchical parenthesized structures permit skipping over subtrees without scanning their contents.
The Neurofibromatosis Type 1 (NF1) Gene: Identification and Partial Characterization of a Putative Tumor Suppressor Gene

The NF1 gene has been isolated and partially characterized. The discovery that NF1 functions as a ras GTPase activator protein has led to new opportunities for understanding the pathology of this disease. The approximately 11 kilobase (kb) NF1 consensus cDNA sequence contains an open reading frame encoding a peptide of 2818 amino acids. DNA blot and polymerase chain reaction analysis indicate that the NF1 gene consists of over 50 exons spanning 300 kb of chromosome 17.
The Impact of Testing Frequency on Student Performance in a Marketing Course

Testing frequency has long been examined in the social sciences as an antecedent to student performance in the classroom. However, after nearly 70 years of study, the results are inconclusive. Given the developments in computerized testing over the last decade, professors now have the ability to create and conduct frequent tests without severely impinging on other duties. In this article, the authors reexamine the issue in a marketing context, and the findings suggest that, under certain conditions, students tend to perform better with more frequent testing. In addition, more frequent testing tends to increase student evaluations of faculty. The authors also discuss reasons for and limitations of these findings.
Conditional RNA Interference Mediated by Allosteric Ribozyme

Conditional RNA interference (RNAi) enables spatial and/or temporal control over gene silencing. The currently available methods require coexpression of engineered proteins and/or modified promoters which may limit their applications. We designed a novel RNA architecture that combines a drug-inducible allosteric ribozyme with a microRNA precursor analogue that allows chemical induction of RNAi in mammalian cells. The compact and highly modular RNA design should facilitate the construction of conditional RNAi systems that can sense and respond to a variety of molecules recognized by RNA aptamers to regulate virtually any desired genes sensitive to RNAi.