cssi/SciSciGPT-SciSciNet huggingface dataset:
Sclerosing extramedullary hematopoietic tumor: emphasis on diagnosis by renal biopsy

Sclerosing extramedullary hematopoietic tumor (SEMHT) is a rare lesion that typically arises in patients with chronic myeloproliferative disorders. Morphologically, it exhibits atypical megakaryocytes, granulocytic precursors, and erythroid precursors set in a background of dense collagen sclerosis. Sclerosing extramedullary hematopoietic tumor may be easily mistaken for other neoplasms, such as sarcoma, carcinoma, or Hodgkin lymphoma, particularly if pertinent clinical history is not provided. Misdiagnosis may occur because of the difficulty in recognizing the megakaryocytic lineage of the atypical cells and because of the paucity of other hematopoietic elements. We report a case of a 72-year-old man with proteinuria and renal insufficiency who underwent renal biopsy to determine the etiology of the proteinuria. The kidney biopsy demonstrated an unusual tumor in which the initial morphological impression that of sclerosing liposarcoma. However, upon learning of the patient's previous history of chronic idiopathic myelofibrosis and with the aid of immunohistochemistry, the correct diagnosis of sclerosing extramedullary hematopoietic tumor was made. Sclerosing extramedullary hematopoietic tumor should be considered in the differential diagnosis when percutaneous renal biopsy or other intra-abdominal biopsy reveals a sclerotic lesion with interspersed large atypical cells, especially in a patient with a history of chronic myeloproliferative disorder.
The Trace Fossil Paleodictyon within The Cruziana Ichnofacies: First Record from The Devonian in Pennsylvania

Offshore marine deposits of hemipelagic dark-gray shales comprising the Middle Devonian Mahantango Formation have yielded the first evidence of the trace fossil Paleodictyon from Pennsylvania. Paleodictyon occurs in conjunction with a diversity of largely deposit-feeding trace fossils belonging to the Cruziana ichnofacies, and documents another example of a shallower-water occurrence of this ichnofossil in Paleozoic rocks.
Erythropoietin signaling promotes invasiveness of human head and neck squamous cell carcinoma.

Erythropoietin (Epo) is used for managing anemia in cancer patients. However, recent studies have raised concerns for this practice. We investigated the expression and function of Epo and the erythropoietin receptor (EpoR) in tumor biopsies and cell lines from human head and neck cancer. Epo responsiveness of the cell lines was assessed by Epoetin-α-induced tyrosine phosphorylation of the Janus kinase 2 (JAK2) protein kinase. Transmigration assays across Matrigel-coated filters were used to examine the effects of Epoetin-α on cell invasiveness. In 32 biopsies, we observed a significant association between disease progression and expression of Epo and its receptor, EpoR. Expression was highest in malignant cells, particularly within hypoxic and infiltrating tumor regions. Although both Epo and EpoR were expressed in human head and neck carcinoma cell lines, only EpoR was upregulated by hypoxia. Epoetin-α treatment induced prominent JAK2 phosphorylation and enhanced cell invasion. Inhibition of JAK2 phosphorylation reduced both basal and Epo-induced invasiveness. Our findings support a role for autocrine or paracrine Epo signaling in the malignant progression and local invasiveness of head and neck cancer. This mechanism may also be activated by recombinant Epo therapy and could potentially produce detrimental effects in rhEpo-treated cancer patients.
Altered response latencies on visual discrimination tasks in rats with damaged retinas.

Abstract The discrimination performance of rats whose retinas have no apparent receptor cells was compared with the performance of normal, control rats. Retinal degeneration was produced by exposing animals to 30 days of constant illumination at 18 ft-c (184 lux) intensity. Both control rats and those with retinal degeneration were trained and tested in a T-maze on a black-white discrimination. In the pattern task, the discriminanda consisted of targets with alternating black-and-white stripes (0.4 cm wide) oriented either horizontally or vertically. For each animal two measures were used to assess visual performance: the percentage of correct responses to the visual targets and the time taken to make a choice (latency of response). The results showed that latency of response was a more sensitive indicator of retinal damage than was the percentage of correct responses made on the visual task. The results confirmed the findings in previous studies that rats could not only retain a visual habit learned prior to the retinal degeneration, but could learn new discriminations after the retinas were damaged. The extent to which experimental design factors and other variables may influence the kind of results obtained in experiments with retinally damaged rats was discussed.
VACATION HOMES IN THE NORTHEASTERN UNITED STATES: SEASONALITY IN POPULATION DISTRIBUTION

ABSTRACT The vacation home market is emerging as a major force in shaping urban and regional development a result of the seasonal redistribution of the population. Existing urban and regional theory has accounted for the distribution of population only in accordance with the permanent place of residence without considering how this distribution varies on a seasonal or semi-permanent basis. It is estimated that some three-quarters of a million vacation homes currently exist in the more rural areas of Northeastern United States. The seasonal occupancy of these units has important implications for fluctuations in economic base, requirement of community services and facilities, and other factors relating to regional development.
Combining personality and cognitive ability predictors for hiring service-oriented employees.

Recent developments in personality theory and assessment have led to calls for inclusion of personality measures in personnel selection. A measure of service-oriented personality was used in conjunction with cognitive and perceptual ability tests in a concurrent validation study of 202 medical clerical positions. The ability tests explained 5% of criterion variance; an additional 5–8% was accounted for by the personality measures. The results were interpreted as tentative support for broadening use of personality measurement in personnel selection, although a need for greater attention to construct validation was also emphasized.
Genetic structure and domains of DNA polymerase III of Bacillus subtilis

We have determined the nucleotide sequence of the polC gene of Bacillus subtilis which codes for DNA polymerase III. Our recent analysis has revealed that the gene comprises 4311 nucleotides, from the start to the stop codon, 306 nucleotides more than we reported earlier. The plasmid reported by us and by N.C. Brown's laboratory contained a sequence at the end of the gene which is not related to the polC region of B. subtilis. We have isolated the rest of the gene, the sequence of which is presented in this paper. The new stop codon is followed by a hyphenated palindromic sequence of 13 nucleotides. The C-terminus' of the coding region contains the novel mutation, dnaF, which results in a defect in the initiation of replication due to a change in the codon TCC to TTC (serine to phenylalanine). The hypermutator mutation mut-1 is due to two point mutations in the 3′ to 5′ exonuclease domain, the proof reading function. The codon changes are GGA to GAA (glycine to glutamic acid) and AGC to AAC (serine to asparagine). The elongation defective mutation, polC26, affecting the catalytic site that adds nucleotides to the growing chain, is due to a change in the codon GTC to GAC (valine to aspartic acid). It is separated from the mutation reported earlier, azp-12, by 306 nucleotides. Knowing the locations of the mutational sites allowed us to deduce the domains of the gene and the enzyme it encodes, and permitted us to present a precise map of the gene at the molecular level.
Kinetic control of negative feedback regulators of NF-κB/RelA determines their pathogen- and cytokine-receptor signaling specificity

Mammalian signaling networks contain an abundance of negative feedback regulators that may have overlapping (“fail-safe”) or specific functions. Within the NF-κB signaling module, IκBα is known as a negative feedback regulator, but the newly characterized inhibitor IκBδ is also inducibly expressed in response to inflammatory stimuli. To examine IκBδ's roles in inflammatory signaling, we mathematically modeled the 4-IκB-containing NF-κB signaling module and developed a computational phenotyping methodology of general applicability. We found that IκBδ, like IκBα, can provide negative feedback, but each functions stimulus-specifically. Whereas IκBδ attenuates persistent, pathogen-triggered signals mediated by TLRs, the more prominent IκBα does not. Instead, IκBα, which functions more rapidly, is primarily involved in determining the temporal profile of NF-κB signaling in response to cytokines that serve intercellular communication. Indeed, when removing the inducing cytokine stimulus by compound deficiency of the tnf gene, we found that the lethality of iκbα−/− mouse was rescued. Finally, we found that IκBδ provides signaling memory owing to its long half-life; it integrates the inflammatory history of the cell to dampen NF-κB responsiveness during sequential stimulation events.
Is an interferon‐like protein involved in the maternal recognition of pregnancy in mares?

Summary To investigate the possibility that an interferon-like protein similar to ovine trophoblast protein 1 (oTP-1) is involved in the maternal recognition of pregnancy in the horse, conceptus membranes were cultured in the presence of a radioactive protein precursor to examine the incorporation of amino acids into proteins similar to oTP-1. There were no proteins of similar isoelectric point or molecular weight range prior to Day 15, the time when maternal recognition of pregnancy should be completed. In addition, there was no immunological cross-reactivity of conceptus-conditioned media from equine conceptus cultures in an oTP-1 radioimmunoassay. Furthermore, bioassay of equine uterine flushings, as well as conceptus-conditioned media did not reveal any antiviral activity, although there was a small amount of antiviral activity measured in yolk sac fluid from a Day 15 equine conceptus. These data do not provide strong evidence for the existence of an oTP-1-like protein from the equine conceptus.
Tenure: Viable or a Dinosaur?

This article discusses the history of tenure in academia as well as the current pros and cons of the tenure system. A review of nursing and non-nursing literature reveals that the most important goal confronting the nation's universities and colleges today is to find more creative ways to define scholarly work and incorporate it into promotion and tenure guidelines. The author presents arguments for and against tenure, reviews the impact of tenure in nursing, and offers recommendations and solutions to the tenure dilemma in nursing.
U.S. immigration policy and family separation: The consequences for children's well-being

At the start of the twenty-first century, two arms of U.S. immigration policy shape the lives of families and children. The first, enforcement practices, lead to the involuntary separation of parents and children-or the fears of this outcome-when the United States government detains and forcibly removes the parents of U.S. citizen children. The second, the policies which restrict migration to the United States, cause children to experience both long and short term separations when their parents migrate without them. In this paper I use interviews collected between the years of 2003-2006 and 2009-2012 with children and their parents or guardians in both the United States and in Mexico to assess the meanings these two types of separations have for families and the potential impacts for children's well-being. I find that enforcement practices create economic and emotional hardship due to feelings of uncertainty, while restrictive immigration policies lead to resentment among children even post-reunification.
Dextromethorphan: A Review of N‐methyl‐d‐aspartate Receptor Antagonist in the Management of Pain

Dextromethorphan (DM) is a noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, which is widely used as an antitussive agent. DM also prevents neuronal damage and modulates pain sensation via noncompetitive antagonism of excitatory amino acids (EAAs). DM has been found to be useful in the treatment of pain in cancer patients and in the treatment of methotrexate-induced neurotoxicity. Clinical studies with DM in cancer patients are reviewed in this article.
Atmospheric gravity waves: their effects on ionospheric temperature and composition

Abstract A model study of the response of the lower F-region electron temperature Te, to the passage of atmospheric gravity waves has been made. It was found that the perturbation in Te is usually of the same order as the perturbation in Tn. This is understandable in view of the fact that the perturbation in production rate and, thereby, in heat input was mostly in phase with the changes in Ne. This meant that higher heat input was associated with a larger number of electrons to share it, in such a way that the changes in Te remained close to the changes in Tn. Gravity wave induced changes in the ion-composition, n(O + ) N e , were also investigated in the context of the radar backscatter determination of thermospheric temperature waves using the double pulse technique. Long period waves (t ∼ 4 hr) with moderate energies (atmospheric motions ≃45 m/sec) may influence the temperature determination, irrespective of the azimuth of their propagation. The extent of the influence will depend upon the sensitivity of the autocorrelation function to the ion composition. For shorter period waves (t ≈ integration time), however, the wave induced composition changes may have to be taken into account only when the wave is propagating in one of the preferred azimuths.
Radiative Meson Decays in Broken SU(3)

We consider vector and pseudoscalar meson decays using vector gauge fields with current mixing. The processes $\ensuremath{\omega}\ensuremath{\rightarrow}3\ensuremath{\pi}$, $\ensuremath{\omega}\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\gamma}$, and $\ensuremath{\pi}\ensuremath{\rightarrow}2\ensuremath{\gamma}$ are fitted with one value of the gauge field's coupling $g$, which also determines leptonic decay rates of vector mesons. Octet breaking of the underlying $\mathrm{VVP}$ strong interaction introduces four parameters. The available experimental information on $\ensuremath{\pi}$, $\ensuremath{\eta}$, $\ensuremath{\omega}$, and $\ensuremath{\phi}$ decays gives relations among these parameters which predict rates for decays such as ${K}^{*}\ensuremath{\rightarrow}K\ensuremath{\gamma}$.
Forced oscillations of pendant drops

The efficiency of droplet/bubble breakup in multiphase contactors can be increased by applying external fields at resonance frequencies of the drops/bubbles. Experimental and theoretical techniques, developed for the study of forced oscillation of pendant drops on nozzles, are used to gain a fundamental understanding of drop response as a function of forcing frequency. Preliminary results of drop oscillations caused by electrical and flow perturbation techniques indicate that the relationship of resonance frequency to drop size for a given fluid system is not affected by the means of excitation. Computational techniques may be used to gain insight into phenomena which are difficult to probe by experiment, such as internal flow fields. The understanding gained by use of these techniques will be indispensable in design and operation of future multiphase contacting devices.
A reaction chamber for isomeric fission measurements

Abstract A reaction chamber has been designed and constructed to allow measurements of the fission modes from isomers having about 10 −2 half life. Fission modes are obtained from coincident measurement of the energies of fragment pairs from each isomeric fission. Mechanical chopper-shutter arrangements were utilized to shield the detectors from prompt fissions during the deuteron bombardment of the target and alternatively to block the deuteron beam while the detectors were exposed to the fission source.
Duff Green, Militant Journalist of the Old School

DUFF Green (born near Versailles, Kentucky, in I791, died at Dalton, Georgia, in I875) as editor of the United States Telegraph "was known and felt from one extremity of the Union to the other."' In fact he and the Telegraph were for a time as well known as Francis P. Blair and the Globe or Horace Greeley and the New York Tribune. A man of versatile interests, wide information, shrewd insight into human nature, with a penchant for political intrigue, and an unflagging industry, he had an interesting and varied career. He was successively a medical student, a school teacher, a surgeon in the War of I8I2, an early "chain store" merchant, a government land surveyor and founder of towns on the frontier, a lawyer, a member of the Missouri Constitutional Convention of I820 and of both houses of the state legislature, a government mail contractor, a brigadier general in Indian warfare, a railroad builder and industrial promoter, a consular and diplomatic agent to Texas and Europe, and a writer on finance and currency, as well as owner and editor of several newspapers. He dabbled in so many things that he succeeded in few; he was often referred to as "the ubiquitous General Green." 2 Green's journalistic career began in I824 when he purchased and became the editor of the St. Louis Enquirer. In the first issue of the paper after he assumed control, Green announced his editorial policy as follows:
Treatment of contact lens-associated corneal erosions.

than other lens solution preservatives, may be the most highly sensitizing of the preservatives. The lesions resembling Trantas dots in our patient represent an IgE-mediated or possibly a toxic reaction to chlorhexidine used as a preservative in the contact lens soaking solution. When contact lens wear is associated with redness and ocular irritation, hypersensitivity to chlorhexidine should be considered. Lens care for the hypersensitive patient should consist of lens storage in a sterile, unit-dose preservative free saline.
Advances in the Regulation of Osteoclasts and Osteoclast Functions

Osteoclasts are derived from mononuclear hematopoietic myeloid lineage cells, which are formed in the bone marrow and are attracted to the bloodstream by factors, including sphingsine-1 phosphate. These circulating precursors are attracted to bone surfaces undergoing resorption by chemokines and other factors expressed at these sites, where they fuse to form multinucleated bone-resorbing cells. All aspects of osteoclast formation and functions are regulated by macrophage-colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL), cytokines essential for osteoclast formation and expressed by a variety of cell types, including osteoblast lineage cells. Since the discovery of RANKL in the mid-1990s, mouse genetic and molecular studies have revealed numerous signaling pathways activated by RANKL and M-CSF. More recent studies indicate that osteoclasts and their precursors regulate immune responses and osteoblast formation and functions by means of direct cell-cell contact through ligands and receptors, such as ephrins and Ephs, and semaphorins and plexins, and through expression of clastokines. There is also growing recognition that osteoclasts are immune cells with roles in immune responses beyond mediating the bone destruction that can accompany them. This article reviews recent advances in the understanding of the molecular mechanisms regulating osteoclast formation and functions and their interactions with other cells in normal and pathologic states.
The Spindle Checkpoint Kinase Bub1 and Cyclin E/Cdk2 Both Contribute to the Establishment of Meiotic Metaphase Arrest by Cytostatic Factor

In vertebrate unfertilized eggs, metaphase arrest in Meiosis II is mediated by an activity known as cytostatic factor (CSF). CSF arrest is dependent upon Mos-dependent activation of the MAPK/Rsk pathway, and Rsk activates the spindle checkpoint kinase Bub1, leading to inhibition of the anaphase-promoting complex (APC), an E3 ubiquitin ligase required for the metaphase/anaphase transition. However, it is not known whether Bub1 is required for the establishment of CSF arrest or whether other pathways also contribute. Here, we show that immunodepletion of Bub1 from egg extracts blocks the ability of Mos to establish CSF arrest, and arrest can be restored by the addition of wild-type, but not kinase-dead, Bub1. The appearance of CSF arrest at Meiosis II may result from coexpression of cyclin E/Cdk2 with the MAPK/Bub1 pathway. Cyclin E/Cdk2 was able to cause metaphase arrest in egg extracts even in the absence of Mos and could also inhibit cyclin B degradation in oocytes when expressed at anaphase of Meiosis I. Once it has been established, metaphase arrest can be maintained in the absence of MAPK, Bub1, or cyclin E/Cdk2 activity. Both pathways are independent of each other, but each appears to block activation of the APC, which is required for cyclin B degradation and the metaphase/anaphase transition.
Seismic soil–foundation–structure interaction observed in geotechnical centrifuge experiments

Abstract This paper reports the experimental results from two geotechnical centrifuge tests examining seismic soil–foundation–structure interaction of frame structures. In the first test, two three-dimensional frame structures were placed apart, and in the second test, the same frame structures were located adjacent to each other. One of the frame structures was founded on shallowly embedded spread footings, and the other was founded on a deeper basement. During the second test, seismic structure–soil–structure interaction was also examined. In this paper, the experimental set-up is described in detail, some kinematic interaction observations are made, and seismic footing response results are reported. The results of the tests indicate that the seismic response of the shallow footings of a flexible frame structure is complex. This result is important because these complexities are not well incorporated in current soil–foundation–structure interaction analysis procedures. The adjacency of two frame structures, and thus structure–soil–structure interaction, further complicates analysis procedures. In the second test, the spread footings rock, slide, and settle less when they are directly adjacent to a deep basement. These results imply that SSSI can be beneficial or detrimental, depending on the earthquake motion and the structural system. In a companion paper, the seismic response of the frame superstructures and the footing force demands are also examined.
Bcl-2 mediates chemoresistance in matched pairs of primary E(mu)-myc lymphomas in vivo.

Abstract ABSTRACT The oncoprotein Bcl-2 is a potent survival factor antagonizing p53-dependent and -independent apoptotic cell death. Although many anticancer agents are known to engage apoptotic pathways, the clinical impact of Bcl-2 on treatment outcome remains controversial. Since it might be difficult to assess the contribution of a single gene to treatment response in patient material due to technical considerations, we sought to address Bcl-2's role in a mouse model of primary lymphomas treated at their natural site. Driven by the Eμ -enhancer controlled c-myc transgene, primary B cell lymphomas arise in this model by several months of age and resemble closely typical clinical and histopathological features of human non-Hodgkin lymphomas. We introduced either bcl-2 or a control construct into identical samples of freshly isolated Eμ-myc lymphomas by retroviral gene transfer in order to obtain matched pairs of primary lymphomas differing only in their Bcl-2 status. While no Bcl-2-mediated effect was detectable in clonogenic survival assays in vitro, treatment of the genetically modified lymphoma pairs propagated in nontransgenic recipient mice revealed Bcl-2`s impact on drug sensitivity in vivo. Bcl-2 efficiently blocked short- and long-term drug-mediated cell death in vivo. In a comparison of 15 matched pairs of primary lymphomas, the bcl-2 transduced sample never achieved longer remission periods than the control counterpart and most of the Bcl-2 overexpressing lymphomas failed to respond at all. We conclude that—when assessed in the physiological environmental context—MBcl-2 contributes to chemoresistance of B cell lymphomas in vivo. This model, able to test any other candidate gene, will be particularly useful to study the implications of specific mutations for drug action in vivo.
Teacher Efficacy in Classroom Management and Discipline

A scale for measuring teacher efficacy in classroom management and discipline is presented, along with results from a factor analysis of intercorrelations of items from the scale and items from two other teacher efficacy scales. Data sources included 119 preservice teacher education students and 42 student teachers. Results are presented indicating that classroom management/discipline efficacy is distinct from other types of teacher efficacy, and that the subscales have acceptable internal consistency and test-retest reliability. The data also indicate that efficacy beliefs predict preferences for certain strategies to deal with problems presented in vignettes; however, no relationships were found between self efficacy scores of student teachers and ratings of teaching performance made by university supervisors.
Selenium metabolism and renal disease

Abstract Selenium's most well-established role is as a component within the active site of the antioxidant enzyme, glutathione peroxidase. Glutathione peroxidase helps prevent the generation of free radicals and decreases the risk of oxidative damage to tissues, including the kidney and its vascular components. Low-selenium intake and status is of concern during chronic renal failure, when dietary protein restrictions are necessary, because dietary selenium is primarily associated with protein. Depressed selenium status occurs frequently in renal patients and should be of concern because of the possible exacerbation of comorbid conditions. Oral and intravenous selenium supplementation has proven to be effective in improving the selenium status and immune function of renal patients, while at the same time decreasing the products of oxidative stress. Therefore, it seems beneficial to monitor selenium status in patients with chronic renal disease and correct less-than-optimal status with careful selenium supplementation.
Resistance of tropoelastin and elastin peptides to degradation by α2-macroglobulin-protease complexes

Abstract Previous studies have suggested that the complex of neutrophil elastase and α2-macroglobulin can degrade tropoelastin, the 70,000-dalton soluble intermediate in the biosynthesis of insoluble elastin. Such complexes could, therefore, play an important role in the development of emphysema. Therefore, complexes of human α2-macroglobulin with homogeneous human neutrophil elastase, porcine pancreatic elastase, or bovine trypsin were isolated by gel filtration chromatography and tested for their ability to degrade tropoelastin. While tropoelastin was rapidly degraded by the free enzymes, it was not affected by the complexes. However, peptides of molecular weight 8500 or less, prepared by mild acid hydrolysis of insoluble elastin, interacted with the catalytically active enzyme in the complex, while larger peptides did not. These findings suggest that α2-macroglobulin-elastase complexes do not, themselves, play a role in the initial degradation of either tropoelastin or insoluble elastin.
Severity of Alcohol Dependence: Impact on Spirituality in Early Treatment Process

Despite the increase in formalized research on the relationship between spirituality and alcohol dependence, a review of the empirical literature highlighted gaps in the research, as the predominant focus has been on the role of spirituality in the recovery process. This study addressed those gaps by examining how the severity of alcohol dependence impacted spiritual beliefs, attitudes, experiences, lifestyle practices, and spiritual well-being in a sample of 180 men and women in early treatment for alcohol and other drug (AOD) problems. Hierarchical multiple regression was used to analyze data. Hypothesis 1 was supported, as increasing severity of alcohol dependence predicted decreasing levels of spiritual well-being. Hypothesis 2 was potentially supported, as increasing severity of alcohol dependence unexpectedly predicted higher levels of existential well-being. Implications for assessment and treatment are discussed.
The role of fragile X mental retardation protein in major mental disorders

Fragile X mental retardation protein (FMRP) is highly enriched in neurons and binds to approximately 4% of mRNAs in mammalian brain. Its loss is a hallmark of fragile X syndrome (FXS), the most common form of mental retardation. In this review we discuss the mutation in the fragile X mental retardation-1 gene (FMR1), that leads to FXS, the role FMRP plays in neuronal cells, experiments from our own laboratory that demonstrate reductions of FMRP in additional psychiatric disorders (autism, schizophrenia, bipolar disorder, and major depressive disorder), and potential therapies to ameliorate the loss of FMRP.
ER Suspensions with ER Active Matrix Liquids

Solutions of polyhexyl isocyanate in xylene, a well known lyotropic liquid crystalline system, are shown to be ER active at concentrations well below those for the onset of a mesophase. This correlates with a field dependent birefringence or orientation induced in the isotropic phase. ER fluids made using these solutions as the liquid phase show an ER activity much greater than just the sum of ER properties of the solutions and the particles in inert fluids, i.e., the effects are synergistic. A greatly enhanced birefringence between the particles is observed under electric field. The effects are explained as due to both a much greater orientation of and increased concentration of polymer between the particles. These effects are not observed for solutions of polystyrene.
Centromeric genotyping and direct analysis of nondisjunction in humans: Down syndrome

In species with chiasmate meioses, alterations in genetic recombination are an important correlate of nondisjunction. In general, these alterations fall into one of two categories: either homologous chromosomes fail to pair and/or recombine at meiosis I, or they are united by chiasmata that are suboptimally positioned. Recent studies of human nondisjunction suggest that these relationships apply to our species as well. However, methodological limitations in human genetic mapping have made it difficult to determine whether the important determinant(s) in human nondisjunction is absent recombination, altered recombination, or both. In the present report, we describe somatic cell hybrid studies of chromosome 21 nondisjunction aimed at overcoming this limitation. By using hybrids to “capture” individual chromosomes 21 of the proband and parent of origin of trisomy, it is possible to identify complementary recombinant meiotic products, and thereby to uncover crossovers that cannot be detected by conventional mapping methods. In the present report, we summarize studies of 23 cases. Our results indicate that recombination in proximal 21q is infrequent in trisomy-generating meioses and that, in a proportion of the meioses, recombination does not occur anywhere on 21q. Thus, our observations indicate that failure to recombine is responsible for a proportion of trisomy 21 cases.
Regular and Singular Points

Suppose ϕ is a flow in \( {mathbb{S}^2} \), and \( S{\rm{(}}\varphi {\rm{)}}\;{\rm{ = }}\;square. \) □. As we shall show later, the behaviour of ϕ is very simple. In fact, if Ω ia any component of \( G(\varphi ) \), then Ω is an annulus, and if x ∈ Ω, then either (i) \( {O_\varphi }(x) \) is a Jordan curve which separates ∂(Ω), or (ii) pϕ (x) = ∞, and there exist z1 and z2 in Ω, such that \( {O_\varphi }({z_1}) \) and \( {O_\varphi }({z_2}) \) are Jordan curves, x belongs to the annulus A between \( {O_\varphi }({z_1}) \) and \( {O_\varphi }({z_2}) \), and each point x′ ∈ A satisfies that \( {O_\varphi }(x') \) α-spirals to \( {O_\varphi }({z_1}) \) and ω-spirals to \( {O_\varphi }({z_2}) \).
Supraventricular Tachycardia Treatment Efficacy in Infants On Further Review

In this issue of Circulation: Arrhythmia and Electrophysiology , Sanatani et al1 report a randomized, double-blind study of a comparison of digoxin and propranolol for chronic therapy of supraventricular tachycardia (SVT) in infants <4 months of age. The key findings in 61 patients were that there were no differences in SVT recurrence for the 2 drug treatment groups and that there were no recurrences of SVT after 4 months of therapy with either antiarrhythmic agent. Another salient point to be taken includes an expectation that perhaps 10% of infants diagnosed with SVT can be expected to require subsequent hospitalization for management of SVT recurrences. Article see p 984 As is often the case with even thoughtful attempts to perform these types of clinical trials in pediatric electrophysiology, and pediatric cardiology generally, the study is underpowered to make feasible many of the desired statistical analyses between the 2 treatment groups. As a result of the relatively small numbers of patients in a given institution, multicenter studies in our field are frequently required to achieve the requisite N for these study designs. As the authors note, issues of patient enrollment, physician biases, parental consent, and inadequate follow-up plague this and other similar efforts. The history of this specific article is telling, in its attempts to clear the hurdle of peer …
Venture Capital and the Structure of Capital Markets: Banks Versus Stock Markets

The United States has many banks that are small relative to large corporations and play a limited role in corporate governance, and a well developed stock market with an associated market for corporate control. In contrast, Japanese and German banks are fewer in number but larger in relative size and are said to play a central governance role. Neither country has an active market for corporate control. We extend the debate on the relative efficiency of bank- and stock market-centered capital markets by developing a further systematic difference between the two systems: the greater vitality of venture capital in stock market-centered systems. Understanding the link between the stock market and the venture capital market requires understanding the contractual arrangements between entrepreneurs and venture capital providers; especially the importance of the opportunity to enter into an implicit contract over control, which gives a successful entrepreneur the option to reacquire control from the venture capitalist by using an initial public offering as the means by which the venture capitalist exits from a portfolio investment. We also extend the literature on venture capital contracting by offering an explanation for two central characteristics of the U.S. venture capital market: relatively rapid exit by venture capital providers from investments in portfolio companies; and the common practice of exit through an initial public offering.
Homeless Children and Youth at Risk: The Educational Impact of Displacement

We know that homelessness creates conditions of risk for homeless children and youth (e.g., malnutrition, missing parental support, affiliation with deviant peers, disconnect from schooling, and so forth). Researchers also document that these states of risk have devastating physical, emotional, social, and educational impacts on young people. In this article, we explore the final issue—how displacement affects the educational well-being of homeless children and youth. We begin our review with a variable—mobility—that has a good deal of explanatory power for the educational impacts examined. We conclude with the consequences of homelessness that follow displaced children and youth into adulthood. In between we discuss an assortment of outcome factors: placement in special education, attendance, academic success, and graduation.
Off the Record: Unrecorded Legislative Votes, Selection Bias and Roll-Call Vote Analysis

Scholars often use roll-call votes to study legislative behaviour. However, many legislatures only conclude a minority of decisions by roll call. Thus, if these votes are not a random sample of the universe of votes cast, scholars may be drawing misleading inferences. In fact, theories over why roll-call votes are requested would predict selection bias based on exactly the characteristics of legislative voting that scholars have most heavily studied. This article demonstrates the character and severity of this sampling problem empirically by examining European Parliament vote data for a whole year. Given that many legislatures decided only a fraction of their legislation by roll call, these findings have potentially important implications for the general study of legislative behaviour.
Sensitivity of the Southern San Andreas Fault System to Tectonic Boundary Conditions and Fault Configurations

The southern Big Bend of the San Andreas fault (SAF) accommodates transpression along numerous non‐vertical, non‐planar, and intersecting active surfaces. Using three‐dimensional boundary element method (BEM) models, we test the sensitivity of fault slip rates to a range of tectonic boundary conditions constrained by Global Positioning System (GPS) studies of the region (45–50 mm/yr and 320°–325°). Using this approach, our models provide a range of distributed fault slip rates associated with both spatial variations in geometry and present‐day uncertainties in plate motion. Model slip rates match most of the available geologic slip rates, and discrepancies may owe to inaccurate fault geometries. More northerly plate velocity (325°) produces greater transpression along the SAF system associated with greater uplift of the San Bernardino Mountains, greater reverse‐slip rates along range bounding reverse thrust faults, lower strike‐slip rates along the San Andreas and San Jacinto faults, and greater strike‐slip rates along the Eastern California Shear Zone (ECSZ) and Garlock fault. These results suggest that the degree of regional transpression controls the partitioning of deformation between uplift, and slip along both the SAF system and the ECSZ. The insensitivity of modeled slip rates to applied velocity along the southern San Andreas and San Jacinto faults suggests that fault geometry greatly influences slip rates within the San Bernardino Mountains region. A northerly shift in plate velocity orientation could account for the abandonment of the Mill Creek strand of the SAF>95 ka and development of the present‐day active geometry, which accommodates greater uplift.
The application of flux corrected transport to transient electromagnetic phenomena

The authors describe the application of flux-corrected transport (FCT), a scheme which allows the accurate numerical analysis of waveshapes that have steep leading or trailing edges. The idea behind the method is to use both a lower-order and, separately, a higher-order approximation to the spatial derivative. The solutions are then combined node by node using a nonlinear weighting scheme that does not allow new maxima or minima to form. The method of FCT is discussed in the context of applications to time-dependent electromagnetic problems. The results indicate a drastic improvement in the solution in regions where steep gradients appear as in pulse propagation. The results of the addition of FCT to the original Lax-Wendroff algorithm are presented. It can be seen that the wavefront is maintained without the additional burden of ripples in the solution. >
Role of Ezetimibe in Lipid-Lowering and Cardiovascular Disease Prevention

With the goal of decreasing low-density cholesterol (LDL-C) to mitigate risk of both primary and secondary cardiovascular outcomes, statins have been the cornerstone of therapy, significantly reducing the incidence of coronary atherosclerotic vascular disease. Previous studies suggest that adding other non-statin LDL-lowering agents may further lower LDL-C without negative side effects. Recent guidelines support the hypothesis that driving the LDL-C level below previously recommended targets may have a beneficial effect. Ezetimibe, a cholesterol absorption blocker that inhibits the Niemann-Pick C1-Like 1 (NPC1L1) receptor, has been the focus of recent trials that support its use in cardiovascular risk reduction. For patients not at goal on statin therapy alone, ezetimibe has proven to be a safe, well-tolerated medication that may be used as an adjunct to statin therapy to further reduce LDL-C, resulting in a significant mortality benefit.
Hypertext and Instructional Design: Some Preliminary Guidelines

Hypertext is a nonlinear way of presenting content consisting of nodes and links that a person can access using a variety of search and browsing strategies. In this article, we focus on the use of hypertext as an instructional tool. We compare hypertext instruction with traditional instructional formats. We offer some initial guidelines relating to guidance and control, development and implementation, multiuser management, user interface, and content representation. The paper concludes with a discussion of limitations of learner control as an instructional strategy, and the need for careful instructional design of hypertext instructional programs.
Grey matter abnormalities in multiple sclerosis: proton magnetic resonance spectroscopic imaging

Pathologically defined abnormalities in the cortical gray matter (GM) are well described in multiple sclerosis (MS) but are infrequently seen by conventional magnetic resonance imaging (MRI). We systematically evaluated 52 relapsing-remitting MS patients and 20 normal volunteers with high resolution MRI and short echo proton magnetic resonance spectroscopic imaging (MRSI). Individual tissue contributions to the spectroscopic voxels were estimated based on MRI that incorporated both CSF suppression and magnetization transfer, or double inversion images in which both CSF and GM were suppressed. Strong resonances in the 0.8 to 1.5 p.p.m. spectral region were observed in 13 MS patients. Image segmentation based on the MRI characteristics of tissues contributing to the spectroscopic voxels showed that these additional peaks originated mainly from GM. The presence of these additional peaks suggests that the normal appearance GM on MRI, is biochemically abnormal in a substantial proportion of relapsing-remitting MS patients.
Gravestones and Monuments in the Maritime Cultural Landscape: Research Potential and Preliminary Interpretations

Thousands of memorials around the world commemorate maritime disasters and death. In addition to commemoration, memorials provide insight into the conceptual landscape of maritime peoples. Types of...
Incidence of shunt occlusion or stenosis following transjugular intrahepatic portosystemic shunt placement.

Abstract Background/Aims: Transjugular intrahepatic portosystemic shunt (TIPS) placement has been used for the treatment of recurrent variceal hemorrhage. The 1-year incidence of shunt stenosis or occlusion after TIPS placement was prospectively assessed, and the accuracy of Doppler ultrasonography to predict TIPS stenosis was evaluated. Methods: Twenty-two patients with recurrent variceal hemorrhage were selected for TIPS placement between April 1991 and May 1992. Preoperative and postoperative evaluation included clinical assessment, upper gastrointestinal endoscopy, portal angiography with pressure measurements, and Doppler ultrasonography. Follow-up was performed at 3 and 12 months post-TIPS and when patients developed recurrent bleeding. Results: Twenty-one of 22 patients (Child-Pugh class A-1, B-11, C-9) had successful TIPS placement. Seventeen of 21 patients have completed follow-up for at least 12 months. Of these 17 patients, 2 of 17 (12%) developed TIPS occlusion, 7 of 17 (41%) developed shunt stenosis, and 8 of 17 (47%) showed no stenosis on follow-up angiography. Doppler ultrasonographic assessment of the TIPS predicted shunt stenosis or occlusion with 100% sensitivity, 98% specificity, and 90% positive predictive value. Conclusions: Shunt occlusion or stenosis develops frequently within 12 months after TIPS placement, and Doppler ultrasonography is accurate in the noninvasive assessment of shunt stenosis. TIPS placement without careful follow-up and shunt revision cannot be considered a long-term treatment of variceal hemorrhage.
Compressed Sensing Vs. Active Learning

Compressive sampling (CS), or Compressed Sensing, has generated a tremendous amount of excitement in the signal processing community. Compressive sampling, which involves non-traditional samples in the form of randomized projections, can capture most of the salient information in a signal with a relatively small number of samples, often far fewer samples than required using traditional sampling schemes. Adaptive sampling (AS), also called Active Learning, uses information gleaned from previous observations (e.g., feedback) to focus the sampling process. Theoretical and experimental results have shown that adaptive sampling can dramatically outperform conventional (non-adaptive) sampling schemes. This paper compares the theoretical performance of compressive and adaptive sampling in noisy conditions, and it is shown that for certain classes of piecewise constant signals and high SNR regimes both CS and AS are near-optimal. This result is remarkable since it is the first evidence that shows that compressive sampling, which is non-adaptive, cannot be significantly outperformed by any other method (including adaptive sampling procedures), even in presence of noise.
Muon acceleration to 750 GeV in the Tevatron tunnel for a 1.5 TeV μ + μ - collider

Muon acceleration from 30 to 750 GeV in 72 orbits using two rings in the 1000 m radius Tevatron tunnel is explored. The first ring ramps at 400 Hz and accelerates muons from 30 to 400 GeV in 28 orbits using 14 GV of 1.3 GHz superconducting RF. The ring duplicates the Fermilab 400 GeV main ring FODO lattice, which had a 61 m cell length. Muon survival is 80%. The second ring accelerates muons from 400 to 750 GeV in 44 orbits using 8 GV of 1.3 GHz superconducting RF. The 30 T/m main ring quadrupoles are lengthened 87% to 3.3 m. The four main ring dipoles in each half cell are replaced by three dipoles which ramp at 550 Hz from -1.8 T to +1.8T interleaved with two 8 T fixed superconducting dipoles. The ramping and superconducting dipoles oppose each other at 400 GeV and act in unison at 750 GeV. Muon survival is 92%. Two mm copper wire, 0.28 mm grain oriented silicon steel laminations, and a low duty cycle mitigate eddy current losses. Low emittance muon bunches allow small aperatures and permit magnets to ramp with a few thousand volts. Little civil construction is required. The tunnel exists.
Cost-Effectiveness Comparison of Renal Calculi Treated with Ureteroscopic Laser Lithotripsy Versus Shockwave Lithotripsy

Abstract Purpose: To evaluate the cost-effectiveness of shockwave lithotripsy (SWL) vs ureteroscopic lithotripsy (URS) for patients with renal stones <1.5 cm in diameter. Methods: Patient age, stone diameter, stone location, and stone-free status were recorded for patients treated with SWL or URS for renal stones <1.5 cm in maximal diameter over a 1-year period. Institutional charges were obtained from in-house billing. A decision analysis model was constructed to compare the cost-effectiveness of SWL and URS and using our results and success rates for modeling. Three separate models were created to reflect practice patterns for SWL. Results: One hundred fifty-eight patients were included in the study—78 underwent SWL and 80 underwent URS as primary treatment. Single procedure stone-free rates (SFR) for SWL and URS were 55% and 95%, respectively (P<0.0001). Decision analysis modeling demonstrated cost-effectiveness of SWL when SWL single procedure SFR were 65% to 67% or when URS single procedure SFR was 7...