cssi/SciSciGPT-SciSciNet huggingface dataset:
Nitrogen utilization by the raphidophyte Heterosigma akashiwo: Growth and uptake kinetics in laboratory cultures

Abstract The nitrogen uptake and growth capabilities of the potentially harmful, raphidophycean flagellate Heterosigma akashiwo (Hada) Sournia were examined in unialgal batch cultures (strain CCMP 1912). Growth rates as a function of three nitrogen substrates (ammonium, nitrate and urea) were determined at saturating and sub-saturating photosynthetic photon flux densities (PPFDs). At saturating PPFD (110 μE m−2 s−1), the growth rate of H. akashiwo was slightly greater for cells grown on NH4+ (0.89 d−1) compared to cells grown on NO3− or urea, which had identical growth rates (0.82 d−1). At sub-saturating PPFD (40 μE m−2 s−1), both urea- and NH4+-grown cells grew faster than NO3−-grown cells (0.61, 0.57 and 0.46 d−1, respectively). The N uptake kinetic parameters were investigated using exponentially growing batch cultures of H. akashiwo and the 15N-tracer technique. Maximum specific uptake rates (Vmax) for unialgal cultures grown at 15 °C and saturating PPFD (110 μE m−2 s−1) were 28.0, 18.0 and 2.89 × 10−3 h−1 for NH4+, NO3− and urea, respectively. The traditional measure of nutrient affinity—the half saturation constants (Ks) were similar for NH4+ and NO3− (1.44 and 1.47 μg-at N L−1), but substantially lower for urea (0.42 μg-at N L−1). Whereas the α parameter (α = Vmax/Ks), which is considered a more robust indicator for substrate affinity when substrate concentrations are low ( NO3− > urea, and suggests that natural blooms of H. akashiwo may be initiated or maintained by any of the three nitrogen substrates examined.
Characterization of alpha- and beta-adrenergic receptors in membranes prepared from the rabbit iris before and after development of supersensitivity.

Abstract α-Adrenergic and β-adrenergic receptors were studied by measuring the binding of [ 3 H]dihydroergocryptine and [ 3 H]dihydroalprenolol, respectively, to membranes prepared from homo-genized rabbit irides. The binding of [ 3 H]dihydroergocryptine appears to be specific for α-adrenergic receptors as adrenergic agents displace this radioligand with the following order of potency: phentolamine > epinephrine ⩾ norepinephrine ⪢ isoproterenol = propranolol. The binding of [ 3 H]dihydroalprenolol appears to be specific for β-adrenergic receptors as adrenergic agents displace this radioligand with the following order of potency: propranolol ⪢ isoproterenol ⩾ epinephrine > norepinephrine ⪢ phentolamine. Several weeks after removal of the superior cervical ganglion, when all the adrenergic nerves to the tissue have degenerated, membranes prepared from denervated irides have an increased density of β-adrenergic receptors with no increase in the density of α-adrenergic receptors. A small decrease in the total number of α-adrenergic receptors probably occurs, which is due to the loss of pre-junctional receptors. The affinities of the receptors do not change. These findings suggest that unlike skeletal muscle, the supersensitivity that occurs in smooth muscle is not due to an increase in the population of receptors governing contraction. However, the change in population of β-adrenergic receptors is consistent with the hypothesis that, as in other tissues, the level of cyclic AMP modulates the density of the β-adrenergic receptor.
Hemosiderin Granules: Cytotoxic Response to Arsenic Exposure in Channel Catfish

Adult channel catfish were exposed to 0 or 15 ppm arsenic as sodium arsenate in synthetic lake water for approximately six months. After sacrifice, livers were removed and examined by conventional transmission electron microscopy, optical microscopy, scanning electron microscopy, and electron probe X-ray microanalysis. Cytoplasmic structures in the nuclei were found to contain highly concentrated deposits of iron. Thirty percent of these structures were also found to contain arsenic at a level above the minimum detectable level for the conditions of the study. The size, shape and relative position of the cytoplasmic structures were the same as the hemosiderin granules observed by conventional transmission electron microscopy. (JMT)
Visual interfaces for operation of non-line-of-sight mobile manipulation

Early applications of mobile robots focused on reconnaissance, surveillance, and target acquisition (RSTA) or related activities. For such scenarios, a significant body of experience has been developed related to the use of camera feedback for non-line-of-sight (NLOS) tele-operation for basic robot motion control (or driving) and remote surveillance. Recently, there has been increased interest in enhancing the capabilities of mobile platforms through the addition of robotic arms and manipulators, thus allowing remote manipulation of payloads or other devices in the environment (e.g., disarming explosives in a military application). In this case, the demands on the remote vision system become very different, as there are various modes in which the user can gain awareness of the motion of the platform and the manipulator arm. This includes robot view (typical driving camera), the view from an arm-mounted camera (eye-inhand), and possibly the view from a fixed camera or from a camera mounted on the robot that captures the complete arm motion (scene view). To date, there have been few systematic studies that compare and contrast these different approaches to operator visual interfaces for NLOS robot and arm control interfaces. In this paper we address this problem, presenting a systematic, controlled, statistical study involving multiple subjects performing multiple trials of a NLOS tele-operated mobile manipulation task. The results of the study can be used to guide the development of operator visual interfaces for mobile manipulators.
Blood Pressure Goals and Treatment in Pregnant Patients With Chronic Kidney Disease

As the age of pregnant women and prevalence of obesity and diabetes are increasing, so is the prevalence of medical disorders during pregnancy, particularly hypertension and the associated CKD. Pregnancy can worsen kidney function in women with severe disease, and hypertension puts them at risk for pre-eclampsia and the associated complications. There are no specific guidelines for hypertension management in this population, and tight control will not prevent pre-eclampsia. Women with end-stage kidney disease should be placed on intense dialysis regimens to improve obstetric outcomes, and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are best avoided. This article will review the rationale for a management plan that includes a multidisciplinary team to discuss risks and develop a plan before conception, antepartum monitoring for maternal and fetal morbidity, individualization of medical management using medications with established records during pregnancy, and balancing the level of blood pressure control proved to protect kidney function against the potential effects that aggressive blood pressure control could have on the fetal-placental unit.
Ocular trauma associated with Pickwickian syndrome

Abstract We describe a case of ocular trauma resulting from a fall sustained by a 46-year-old male with a long standing history of obesity–hypoventilation (Pickwickian) syndrome (OHS). The patient had several episodes of narcolepsy while standing secondary to sleep deprivation. He presented with left eye trauma after falling asleep while standing. Surgical exploration of left eye revealed a 200° scleral rupture with uveal prolapse which was located 13 mm posterior to the limbus. Attempted repair was unsuccessful. Enucleation of left eye was performed 8 days later to prevent occurrence of sympathetic ophthalmia. Pickwickian syndrome, also known as obesity–hypoventilation syndrome, is a severe form of sleep apnea in obese persons. Impaired ventilation can result in poor gas exchange and hypersomnolence. An unappreciated complication of hypersomnolence, especially in OHS, may be ocular trauma.
MOCVD precursor design issues. Recent advances in the chemistry and vapor pressure characteristics of Ba(hexafluoroacetylacetonate)2·polyether complexes

Abstract This contribution presents synthetic, structural and volatility results for a series of new Ba(hfa) 2 polyether (hfa=1,1,1,5,5,5-hexafluoropentane-2,4-dionate) MOCVD precursors. The major emphasis of this study is on the synthesis and characterization of new Ba(hexafluoroacetylacetonate) 2 ·polyether complexes as on well as elucidating relationships between volatility, melting point and molecular architecture using a variety of techniques, including reduced pressure thermogravimetric analysis (TGA). The results provide insights into tuning Ba precursor volatility characteristics based on straightforward modifications of the polyether structure.
Alterations of coronary collateral blood flow velocity during intraaortic balloon pumping

Abstract Controversy exists regarding the ability of intraaortic balloon pumping to increase coronary blood flow either directly or through collateral perfusion. 1–4 In patients, directly measured coronary flow velocity by intracoronary Doppler guidewire technique distal to severe coronary stenoses is minimal and unaffected by intraaortic balloon pumping. 5 After coronary angioplasty, intraaortic balloon pumping increases both proximal and, more importantly, distal coronary artery flow velocity. 5 Whether collateral flow is altered during intraaortic balloon pumping has not been adequately studied in humans because of a lack of quantitative means to assess collateral blood flow. 6 With the use of a Doppler-tipped angioplasty guidewire, retrograde collateral flow velocity can be directly measured, and thus quantitate the effects of interventions altering collateral blood flow responses. 7 While performing angioplasty with the Doppler guidewire, we quantitated intracoronary collateral blood flow alterations during intraaortic balloon pumping in 3 patients: 2 with acute myocardial infarction and 1 with unstable angina. These observations using flow velocity techniques to evaluate perturbations of collateral flow are the first physiologic demonstrations in patients of one of the unique hypothesized beneficial antiischemic mechanisms of intraaortic balloon pumping.
Coexistence of prostate cancer and dysfunctional bladder neck obstruction

The etiology of dysfunctional bladder neck obstruction remains elusive. Obstruction has been attributed to muscular hypertrophy, fibrosis, scarring, and neurologic dysfunction of the bladder neck opening mechanism. We describe two patients with urodynamic findings of dysfunctional bladder neck obstruction who proved to have stage A1 prostate adenocarcinoma on transurethral prostate biopsies obtained at the time of surgery. We recommend that the transurethral surgical treatment of men over the age of 40 years with dysfunctional bladder neck obstruction include a biopsy for histological examination.
The real part of the optical potential in proton-nucleus scattering

Abstract The real parts of the central and spin-orbit optical potential are calculated for 40 MeV protons on 40Ca, 58Ni, 120Sn and 208Pb to first order in the two-nucleon effective interaction. Two estimates were used for the effective interaction. The first estimate was obtained from the impulse approximation and the second from the “bare” effective shell-model interaction as calculated by Kuo and Brown and by Green.
Polyamines and estrogen control of growth of the NMU-induced rat mammary tumor.

Recentin vitro evidence suggests that polyamines play an important role in the growth of the N-nitrosomethyl-urea (NMU)-induced rat mammary tumor, and that they may be involved in mediating the effect of estrogens on tumor growth. In support of this hypothesis, we here show that inhibition of polyamine biosynthesis with α-difluoromethyl-ornithine (DFMO) blocks the mitogenic effect of estradiol-17β (E2) added to NMU-mammary tumors grown in soft agar in the presence of the antiestrogen tamoxifen (Tam). Exogenous polyamine administration reversed the inhibitory effect of DFMO and restored E2 action. Administration of polyamine inhibitors to NMU-tumor-bearing rats induced significant inhibition of tumor growth, although tumor ornithine decarboxylase (ODC) was not consistently suppressed. Under our experimental conditions, such treatment did not potentiate the antitumor effect of Tam. Tam alone was found to suppress tumor ODC, suggesting a possible involvement of the polyamine pathway in its antitumor action. These data suggest that the polyamines may play an important role in the hormonal control of the growth of this experimental breast cancer.
Potency of conditioned reinforcers based on food and on food and punishment.

Pigeons peck more frequently on the left key of two keys when food is presented more frequently during the stimulus that reinforces pecks on that key than during the stimulus that reinforces pecks on the right key. This preference can be annulled and reversed by punishing each peck on the left key during the stimulus that reinforces pecks on the left key.
A serum inhibitor of blastogenesis in idiopathic nephrotic syndrome transferred by lymphocytes.

Abstract Suppression of concanavalin A- and phytohemagglutinin-induced lymphoblastogenesis was observed when serum from patients with hypoalbuminemia constituted 20% by volume of the culture medium. There was no evidence for a lymphocytotoxin or for absence of a factor essential for blastogenesis. Transfer experiments using serum from patients with idiopathic nephrotic syndrome (INS) indicated the presence of a heat-stable inhibitor with marked affinity for lymphocytes. A factor in normal serum appeared to block attachment of the inhibitor but was less firmly cell bound. Paradoxically, lymphocytes isolated from patients with INS with circulating inhibitor responded normally to mitogens, probably because receptors on lymphocytes for the inhibitor were masked by the normal serum factor. Washing entailed in harvesting the cells would make them susceptible to the inhibitor.
Induction of thymidine kinase by vaccinia-infected mouse fibroblasts.

The thymidine kinase activity of suspension cultures of L-M mouse fibroblasts was markedly enhanced following vaccinia infection. The increase in enzymic activity was greater and occurred more rapidly as the multiplicity of virus to cells increased from 0·5 to 10 ID 50 § per cell. L-M cells incubated with u.v. or heat-inactivated vaccinia did not show increased thymidine kinase activity. The pH optimum and various other properties of the enzyme from infected cells did not differ significantly from those of the enzyme from non-infected cells. Vaccinia stimulation of thymidine kinase activity was observed in L-M cells cultivated in the presence of thymidine and in cells at 1 day or 2 days after subculture. A bromodeoxyuridine-resistant subline of L-M cells has been selected. These resistant cells [L-M ( TK − )] have lost the capacity to phosphorylate thymidine. However, highly active enzymic extracts have been prepared following infection of L-M ( TK − ) cells with vaccinia. The increase in thymidine kinase activity was markedly inhibited in vaccinia-infected cells when incubated with p -fluorophenylalanine§ in a phenylalanine-deficient medium. Non-infected cells incubated with fluorophenylalanine also manifested inhibited enzymic activity. These effects were reversed by phenylalanine.
Transparent Pedagogy: Visions for a Contemporary Public School

In this second-year graduate studio at the University of Pennsylvania, students generated different spatial and tectonic models by scrutinizing the dynamic conditions inherent in transpare...
Diastolic Mitral Regurgitation in Patients With Hypertrophic Cardiomyopathy

An analysis of the left ventricular angiograms of 31 patients with hyper trophic cardiomyopathy revealed diastolic mitral regurgitation in 4, a preva lence of 12.9%. The clinical, echocardiographic, angiographic, and hemo dynamic data of these patients were reviewed. Diastolic mitral regurgitation could not be attributed to arrhythmia, PR interval prolongation, atrioventricu lar dissociation, aortic insufficiency, or aortic stenosis. Reduced left ventricular compliance was evidenced by elevated end-diastolic pressure following angiog raphy and reduced diastolic E-F slope on echocardiography. It is speculated that the rapid inflow of blood into a poorly compliant ventricle established a turbulent flow pattern that resulted in the "floating" of blood back into the left atrium.
Confidentiality vs. mandated reporting of child abuse: a social work research dilemma

The tension between protecting the privacy rights of a respondent and the legally mandated obligation to report suspicion of child abuse confronts the researcher with a dilemma: to breach confidentiality is unethical; to not report is illegal. Example cases are presented in which the reporting of suspected child abuse breaches respondent confidentiality. The argument is advanced that the decision to breach confidentiality may well lead to: self-censorship by researchers, lack of candor by respondents, suppressed survey response rates, interviewer deception, oppression of disempowered groups, and impairment of the self-correcting aspects of disciplined inquiry.
The promise of simulation-based science assessment: the Calipers project

The Calipers project developed and studied a new generation of simulation-based assessment systems. The project aimed to demonstrate the potential of technology- and simulation-based assessments to provide high-quality evidence of complex performances for science tests that address accountability or formative goals. End-of-unit, benchmark assessments for the topics of ecosystems and for forces and motion were developed to test national science standards at the middle school and secondary levels. Technical quality evidence documented the alignment of the assessments with national science standards, expert reviews of content and item quality, cognitive analyses of students thinking-aloud, and analyses of teacher and student data gathered from classroom pilot testing. The project broke new ground in harnessing the affordances of technology to transform what, how, when and where science learning is assessed and to gather evidence of students' connected science knowledge and extended inquiry not well measured by traditional paper-based tests.
Coordinated sampling of dynamic oceanographic features with underwater vehicles and drifters

We extend existing oceanographic sampling methodologies to sample an advecting feature of interest using autonomous robotic platforms. GPS-tracked Lagrangian drifters are used to tag and track a water patch of interest with position updates provided periodically to an autonomous underwater vehicle (AUV) for surveys around the drifter as it moves with ocean currents. Autonomous sampling methods currently rely on geographic waypoint track-line surveys that are suitable for static or slowly changing features. When studying dynamic, rapidly evolving oceanographic features, such methods at best introduce error through insufficient spatial and temporal resolution, and at worst, completely miss the spatial and temporal domain of interest. We demonstrate two approaches for tracking and sampling of advecting oceanographic features. The first relies on extending static-plan AUV surveys (the current state-of-the-art) to sample advecting features. The second approach involves planning of surveys in the drifter or patch frame of reference. We derive a quantitative envelope on patch speeds that can be tracked autonomously by AUVs and drifters and show results from a multi-day off-shore field trial. The results from the trial demonstrate the applicability of our approach to long-term tracking and sampling of advecting features. Additionally, we analyze the data from the trial to identify the sources of error that affect the quality of the surveys carried out. Our work presents the first set of experiments to autonomously observe advecting oceanographic features in the open ocean.
Phage Associated Bacteriocins Reveal a Novel Mechanism for Bacteriocin Diversification in Klebsiella

Ninety-six isolates of Klebsiella pneumoniae and K. oxytoca were recovered from wild mammals in Australia. 14.6% of these bacteria produce killing phenotypes that suggest the production of bacteriocin toxins. Cloning and sequencing of the gene clusters encoding two of these killing phenotypes revealed two instances of a bacteriocin associated with a bacteriophage gene, the first such genetic organization described. The newly identified klebicin C gene cluster was discovered in both K. pneumoniae and K. oxytoca. The newly identified klebicin D gene cluster was detected in K. oxytoca. Protein sequence comparisons and phylogenetic inference suggest that klebicin C is most closely related to the rRNase group of colicins (such as colicin E4), while klebicin D is most closely related to the tRNase group of colicins (such as colicin D). The klebicin C and D gene clusters have similar genetic and regulatory organizations. In both cases, an operon structure is inferred consisting of a phage-associated open reading frame and klebicin activity and associated immunity genes. This novel bacteriophage/bacteriocin organization may provide a novel mechanism for the generation of bacteriocin diversity in Klebsiella.
mStruct: Inference of Population Structure in Light of Both Genetic Admixing and Allele Mutations

Traditional methods for analyzing population structure, such as the Structure program, ignore the influence of the effect of allele mutations between the ancestral and current alleles of genetic markers, which can dramatically influence the accuracy of the structural estimation of current populations. Studying these effects can also reveal additional information about population evolution such as the divergence time and migration history of admixed populations. We propose mStruct, an admixture of population-specific mixtures of inheritance models that addresses the task of structure inference and mutation estimation jointly through a hierarchical Bayesian framework, and a variational algorithm for inference. We validated our method on synthetic data and used it to analyze the Human Genome Diversity Project–Centre d'Etude du Polymorphisme Humain (HGDP–CEPH) cell line panel of microsatellites and HGDP single-nucleotide polymorphism (SNP) data. A comparison of the structural maps of world populations estimated by mStruct and Structure is presented, and we also report potentially interesting mutation patterns in world populations estimated by mStruct.
Diagnóstico pré-natal e aborto seletivo: um desafio à prática e às políticas

Este artigo defende o argumento de que a popularizacao do aborto seletivo com as modernas tecnicas de diagnostico pre-natal representa um risco a integridade moral dos deficientes, caso ele nao seja acompanhado de uma intensificacao das politicas de bem-estar para as pessoas portadoras de deficiencia.
Orienting lipid domains in giant vesicles using an electric field

Directing the orientation of molecular assemblies is a key step toward creating complex hierarchical structures that yield higher order functional materials. Here, we demonstrate the directed orientation of functionalized lipid domains and protein–membrane assemblies, using an electric field.
EFFECT OF Pseudomonas fragi ON THE COLOR OF BEEF

Growth of Pseudomonas fragi had a significant (P > 0.05) effect on the color of beef stored at 1°± 1°C. Beef color was measured with a Hunter Color/Difference Meter and percentages of myoglobin (Mb), oxymyoglobin (O2 Mb), and metmyoglobin (MMb) on meat surfaces were determined using a Beckman DU Spectrophotometer with a reflectance attachment. As surface growth of P. fragi increased from log 2.2 to 7.2/cm2 during 20 days storage at 1°± l°C, the pH increased from 5.5 to 6.6, free fatty acid values (FFA) increased from 0.62 to 2.60 and percent O2 Mb decreased from 100% to 0%. Data indicated that proteolytic and lipolytic degradation products of P. fragi may be important in decreasing the color stability of beef stored at 1°± 1°C.
Understanding Service Experiences of LGBTQ Young People Through an Intersectional Lens

Lesbian, gay, bisexual, transgender, and queer-identified (LGBTQ) young people face forms of stigma and marginalization that position them as needing support and service provision, yet little is known about their service seeking and receiving experiences. This study qualitatively explored the service experiences of a racially and ethnically diverse group of fifteen LGBTQ-identified young people ages 18 to 24. Through their stories, themes were identified that enhance our understanding of the factors that impact effectiveness of services intended to meet their needs. An intersectional analysis of these stories offers insight into the ways that service providers can effectively support LGBTQ young people as they develop into adults.
Climate change and conservation: Nature Conservancy Climate Change Science Conference Portland, Oregon, 5–7 September 2007

The Nature Conservancy (TNC) sponsored its first climate change science conference to bring together scientists and conservation practitioners from around the world to discuss new approaches to conservation. The conference focused on how climate change science can help TNC develop effective strategies to implement in the field. Included at the conference were panel discussions on sea level rise; climate change impacts on freshwater, marine, forest, and cold climate systems; human dimensions of climate change; extinctions, invasives, and migrants; fire in a warming world; how science can inform the climate policy debate; issues of scale and resolution in climate change projections; using information technology to communicate scientific information; and the importance of monitoring networks. Also included was a session on conservation planning and climate change, followed by a lively discussion of potential innovations TNC could engage in.
In Vitro Responses of the Epidermis to Triiodothyronine

The effect of exogenous triiodothyronine on replication and anabolic activity in human epidermis has been studied in vitro Measurements of epidermal replication, as estimated by a labeling index technique and by thymidine incorporation into skin sheets, were increased (p in vitro , and support the concept that there are receptors for triiodothyronine associated with epidermal cells.
Characterization of the eIF2-associated protein p67 during brain ischemia and reperfusion.

Reperfusion after global brain ischemia results in prompt inhibition of translation initiation due to the inactivation of eukaryotic initiation factor 2 (eIF2) recycling by phosphorylation of its α-subunit. There is a 67 kDa peptide (p67) that in its glycosylated form binds to eIF2 and protects eIF2α from phosphorylation, and cells with high p67 content exhibit enhanced resistance to eIF2a phosphorylation. Here we utilized antibodies that recognize total p67, glycosylated p67, and eIF2α(P) to characterize p67 and glycosylated p67 during reperfusion-induced phosphorylation of eIF2a. Neither 10 min complete brain ischemia (cardiac arrest) nor 10 nor 60 min subsequent reperfusion alters the levels of total or glycosylated p67 from those seen in controls. Furthermore, there is no reduction in localized immunostaining for glycosylated p67 in vulnerable neurons during ischemia and reperfusion.
Condition and type of housing as an indicator of potential environmental lead exposure and pediatric blood lead levels.

Abstract Environmental evaluations in a prospective behavioral study of children with blood lead levels up to about 50 μg/dl were performed by an intensive environmental survey and by exterior visual evaluation of housing quality. Serial blood lead values for infants in the study were compared to exterior housing type and quality, which itself was also compared with results of the intensive environmental evaluation. Five housing condition and type categories were defined: public housing; private housing (satisfactory, deteriorated, and dilapidated); and rehabilitated private housing. In this interim report on the first subset of available data, the housing categories were found to differ in paint and environment dust lead levels, with public and rehabilitated housing having lowest values. Blood lead concentrations of children differed across housing categories as early as 6 months of age, with children residing in public housing having lowest levels, followed by those in rehabilitated housing. The spread in mean blood lead concentrations among the housing quality categories increased with increasing age of the children. Housing category accounted for over one-half of the blood lead variability in 18-month-old children.
Real‐time detection of the morphological change in cellulose by a nanomechanical sensor

Up to now, experimental limitations have prevented researchers from achieving the molecular-level understanding for the initial steps of the enzymatic hydrolysis of cellulose, where cellulase breaks down the crystal structure on the surface region of cellulose and exposes cellulose chains for the subsequent hydrolysis by cellulase. Because one of these non-hydrolytic enzymatic steps could be the rate-limiting step for the entire enzymatic hydrolysis of crystalline cellulose by cellulase, being able to analyze and understand these steps is instrumental in uncovering novel leads for improving the efficiency of cellulase. In this communication, we report an innovative application of the microcantilever technique for a real-time assessment of the morphological change of cellulose induced by a treatment of sodium chloride. This sensitive nanomechanical approach to define changes in surface structure of cellulose has the potential to permit a real-time assessment of the effect of the non-hydrolytic activities of cellulase on cellulose and thereby to provide a comprehensive understanding of the initial steps of the enzymatic hydrolysis of cellulose.
NONSOLVABLE POLYNOMIALS WITH FIELD DISCRIMINANT 5 A

We present the first explicitly known polynomials in Z(x) with nonsolvable Galois group and field discriminant of the form ±p A for p 7 a prime. Our main polyno- mial has degree 25, Galois group of the form PSL2(5) 5 .10, and field discriminant 5 69 . A closely related polynomial has degree 120, Galois group of the form SL2(5) 5 .20, and field discriminant 5 311 . We completely describe 5-adic behavior, finding in particular that the root discriminant of both splitting fields is 125·5 1/12500 124.984 and the class number of the latter field is divisible by 5 4 .
Immunity to Whole Varicella-Zoster Virus Antigen and Glycoproteins I and p170: Relation to the Immunizing Regimen of Live Attenuated Varicella Vaccine

Humoral and cellular immune responses to whole varicella-zoster virus (VZV) antigen and the VZV proteins glycoprotein I (gpI) and nonglycosylated protein p170 were evaluated in healthy children and adults given lyophilized live-attenuated varicella vaccine. Children received one dose of vaccine containing 950 pfu, whereas adults received two doses of 2500 pfu. After one year, the antibody titers of adult vaccinees to whole VZV and to gpI were significantly higher than those of children. Antibody titers to whole VZV, gpI, and p170 were lower among both vaccine populations than titers in naturally immune individuals, but vaccinees who seroconverted initially retained detectable VZV antibodies. Using T lymphocyte proliferation to measure cellular immunity, we found the mean (+/- SE) transformation index to whole VZV antigen to be 4.1 +/- 0.96 in children tested at one year, a mean significantly lower than the mean of 12.7 +/- 3.39 in adults and 13.0 +/- 1.67 in naturally immune subjects. These observations suggest that the vaccine dose affects vaccine-induced immunity to VZV.
Effective handling of a large configuration state function expansion for an MCSCF state and improved efficiency for two‐electron integral transformations in MCSCF

Effective solutions for two difficulties which may be present in MCSCF calculation are discussed: (i) We show how the large configuration state function state expansion case may be handled simply and effectively without the introduction of extraneous projection operators or Lagrange multipliers; (ii) we present a simplified two-electron integral transformation procedure which significantly reduces the operation count (and hence computational efficiency is increased) for second order and particularly for third order MCSCF procedures. The procedures we introduce use some freedom available in the orthogonal complement Cl space and the virtual orbital space to simplify MCSCF calculations.
The Appendix and IBD: Appendectomy Does Not Protect Against Ulcerative Colitis

It is now almost 9 years since Gilat et al. (I), in their international study of childhood factors in IBD, noted the rarity of appendectomies in patients with ulcerative colitis (UC) compared with their control population. The authors had “no ready explanation” of their finding and did not mention it in their summary. This clear-cut report evoked little interest, and most clinical epidemiologists concentrated on the relationship between IBD and cigarette smoking and sucrose consumption. The more recent report (in 1994) of Rutgeerts et al. (2), who were apparently unfamiliar with the older study confirming the rarity of appendectomy in UC, has revived interest in this finding because of the unequivocal title of their article, “Appendectomy Protects Against Ulcerative Colitis” and the suggestion that removal of the appendix might be a useful procedure because “the relative risk of developing UC with an intact appendix exceeds the risk factor associated with smoking.” As a result, the literature now contains six studies on the subject, four full reports, two in abstract form (including one of our own), letters to the Editor, commentary, and editorials, etc.
Stability of an alloy/oxide interface with oxygen ions being the dominant diffusing species in the oxide scale

Abstract The criterion for interfacial stability between an alloy and its oxide was formulated by Wagner [J. electrochem. Soc.103, 571 (1956)] for the specific case when the cations are the diffusing species in the oxide scale. However, for the oxidation of (Pb, In) and (Pb, Sn) alloys, oxygen in the predominant diffusing species in the oxide scales. The criterion formulated by Wagner is no longer applicable. In the present study, the criterion was formulated for the case when oxygen ions are the dominant diffusing species, following the approach used by Wagner. The criterion was used to determine the interfacial stability of (Pb, In)/In2O3. In order to determine the (Pb, In)/In2O3 interfacial stability, it is necessary to know the interdiffusion coefficient of (Pb, In) and the intrinsic diffusion coefficient of oxygen in In2O3. Intrinsic diffusion coefficients for In2O3 are not available and are estimated from the parabolic rate constants for the oxidation of (Pb, In) alloys. Calculations using the interdiffusion coefficient of (Pb, In) from the literature and the estimated intrinsic diffusivity of oxygen indicated that the (Pb, In)/In2O3 interface should be planar.
The hydrolysis and carbonate complexation of strontium and calcium in aqueous solution. Use of molecular modeling calculations in the development of aqueous thermodynamic models

Abstract The hydrolysis and carbonate complexation of the alkaline earth cations Ca 2+ and Sr 2+ were investigated by using a combined experimental and modeling approach. The modeling approach uses both macroscopic thermodynamic models and molecular modeling at the density functional theory (DFT) level. The molecular modeling calculations identify possible speciation schemes in the thermodynamic modeling and provide molecular level insight into the macroscopically observed thermodynamic measurements. In order to develop accurate thermodynamic models valid to high electrolyte concentration and to test for the possible existence of species suggested by the molecular models, experimental measurements were made on the solubility of Ca(OH) 2 , Sr(OH) 2 ·8H 2 O, and carbonate compounds extending to high base molality (≈5 mol kg −1 ), or carbonate molality (≈2 mol kg −1 ). A thermodynamic model is developed that satisfactorily explains the macroscopic aqueous thermodynamic data and correlates with the molecular modeling results. The first published values of the equilibrium constants for the formation of Sr(CO 3 ) 2− 2 (aq) and Ca(CO 3 ) 2− 2 (aq), and of the solubility product of Sr(OH) 2 ·8H 2 O are also provided. In certain cases, specifically when the DFT calculations suggest that the hydroxyl groups are more closely associated with the first hydration layer of water molecules than directly with the central alkaline earth cation, the thermodynamic relations for these cation–hydroxyl interactions are described by means of Pitzer ion-interaction parameters, rather than by the explicit introduction of an aqueous hydrolysis species.
An online video placement policy based on bandwidth to space ratio (BSR)

In a video-on-demand server, resource reservation is required to guarantee continuous delivery. Hence any given storage device (or a striping group treated as a single logical device) can serve only up to a fixed number of client access streams. Each storage device is also limited by the number of video files it can store. For the reasons of availability, incremental growth, and heterogeneity, there may be multiple storage devices in a video server environment. Hence, one or more copies of a particular video may be placed on different storage devices. Since the access rates to different videos are not uniform, there may be load imbalance among the devices. In this paper, we propose a dynamic placement policy (called the Bandwidth to Space Ratio (BSR) Policy) that creates and/or deletes replica of a video, and mixes hot and cold videos so as to make the best use of bandwidth and space of a storage device. The proposed policy is evaluated using a simulation study.
Surgical inpatient satisfaction: what are the real drivers?

Background Inpatient satisfaction is a key element of hospital pay-for-performance programs. Communication and pain management are known to influence results, but additional factors may affect satisfaction scores. We tested the hypothesis that patient factors and outcome parameters not considered previously are clinically important drivers of inpatient satisfaction. Methods Medical records were reviewed for 1,340 surgical patients who returned nationally standardized inpatient satisfaction questionnaires. These patients were managed by 41 surgeons in seven specialties at two academic medical centers. Thirty-two parameters based on the patient, surgeon, outcomes, and survey were measured. Univariate and multivariable analyses were performed. Results Inpatients rated their overall experience favorably 75.7% of the time. Less-satisfied patients were more likely to be female, younger, less ill, taking outpatient narcotics, and admitted via the emergency department (all P P P P Conclusion Several patient factors, expectations of patients with cancer, and postoperative complications are important and clinically relevant drivers of surgical inpatient satisfaction. Programs to manage expectations of cancer patient expectations and decrease postoperative morbidity should improve surgical inpatient satisfaction. Further efforts to risk-adjust patient satisfaction scores should be undertaken.
The impact of prenatal care coordination on birth outcome.

Objective: Care coordination is a Medicaid benefit program designed to assist low-income women in gaining access to pregnancy related services. This study examines the relationship between prenatal care coordination and its impact on access to prenatal services and birth outcome. Methods: Ninety-four women who received prenatal care coordination and gave birth at Wishard Memorial Hospital in 1996 comprised the study population. A control group of 190 non care coordination participants was obtained from women who gave birth immediately before and after the women who was a care coordination participant. The prenatal and birth records from both groups were retrospectively reviewed. Data collected included information on birth weight, gestational age at delivery, WIC participation, number of prenatal visits, smoking and substance abuse. Perinatal complications were also recorded. Statistics was by t test and χ2 with significance at .05. Results: Women enrolled in care coordination received 10 prenatal visits versus 8 for controls (P = .0005). Preterm labor occurred in 1.1% of women in care coordination compared to 5.8% of controls (P = .063). There was no difference in birth weight or the incidence of birth weight <2500 g between care coordination and controls. WIC participation was greater in the care coordination group, 95.7% versus 78% for controls, P < .05. In addition, women with care coordination were less likely to smoke during pregnancy. Conclusions: Care coordination does improve access to prenatal services as evidenced by an increase in prenatal visits and enrollment in WIC services. However, this study failed to demonstrate a direct relationship between care coordination and improved birth outcome.
Anisotropy in high angular resolution diffusion-weighted MRI

The diffusion in voxels with multidirectional fibers can be quite complicated and not necessarily well characterized by the standard diffusion tensor model. High angular resolution diffusion-weighted acquisitions have recently been proposed as a method to investigate such voxels, but the reconstruction methods proposed require sophisticated estimation schemes. We present here a simple algorithm for the identification of diffusion anisotropy based upon the variance of the estimated apparent diffusion coefficient (ADC) as a function of measurement direction. The rationale for this method is discussed, and results in normal human subjects acquired with a novel diffusion-weighted stimulated-echo spiral acquisition are presented which distinguish areas of anisotropy that are not apparent in the relative anisotropy maps derived from the standard diffusion tensor model. Published 2001 Wiley-Liss, Inc.
Blood Samples for Progeria Study

Excerpt To the editor: The New York Hospital-Cornell Medical Center and The Sloan-Kettering Institute are studying patients with progeria and Werner's syndrome. These studies require a small sample...
An analytical solution to proton Bragg peak deflection in a magnetic field

The role of MR imaging for image-guided radiation therapy (IGRT) is becoming more and more important thanks to the excellent soft tissue contrast offered by MRI. Hybrid therapy devices with integrated MRI scanners are under active development for x-ray therapy. The combination of proton therapy with MRI imaging has only been investigated at the theoretical or conceptual level. Of concern is the deflection of the proton beam in the homogeneous magnetic field. A previous publication has come to the conclusion that the impact of a 0.5 T magnetic field on the dose distribution for proton therapy is very small and lateral deflections stay well below 2 mm. The purpose of this study is to provide new insights into the effects of magnetic fields on a proton beam coming to rest in a patient. We performed an analytical calculation of the lateral deflection of protons with initial energies between 50 MeV and 250 MeV, perpendicular to the beam direction and the magnetic field. We used a power-law range-energy relationship and the Lorentz force in both relativistic and non-relativistic conditions. Calculations were done for protons coming to rest in water or soft tissue, and generalized to other uniform and non-uniform media. Results were verified by comparisons with numerical calculations and Monte Carlo simulations. A key result of our calculations is that the maximum lateral deflection at the end of range is proportional to the third power of the initial energy. Accordingly, due to the strong dependence on the energy, even a relatively small magnetic field of 0.5 T will cause a deflection of the proton beam by 1 cm at the end of range of a 200 MeV beam. The maximum deflection at 200 MeV is more than 10 times larger than that of a 90 MeV beam. Relativistic corrections of the deflection are generally small but they can become non-negligible at higher energies around 200 MeV and above. Contrary to previous findings, the lateral deflection of a proton beam can be significant (1 cm and above) even in relatively small magnetic fields of 0.5 T. However, the curved path of a proton beam in a magnetic field is easily predictable and it should be possible to account for this in treatment planning.
Adaptation and visual search in mammographic images

Radiologists face the visually challenging task of detecting suspicious features within the complex and noisy backgrounds characteristic of medical images. We used a search task to examine whether the salience of target features in x-ray mammograms could be enhanced by prior adaptation to the spatial structure of the images. The observers were not radiologists, and thus had no diagnostic training with the images. The stimuli were randomly selected sections from normal mammograms previously classified with BIRADS Density scores of “fatty” versus “dense,” corresponding to differences in the relative quantities of fat versus fibroglandular tissue. These categories reflect conspicuous differences in visual texture, with dense tissue being more likely to obscure lesion detection. The targets were simulated masses corresponding to bright Gaussian spots, superimposed by adding the luminance to the background. A single target was randomly added to each image, with contrast varied over five levels so that they varied from difficult to easy to detect. Reaction times were measured for detecting the target location, before or after adapting to a gray field or to random sequences of a different set of dense or fatty images. Observers were faster at detecting the targets in either dense or fatty images after adapting to the specific background type (dense or fatty) that they were searching within. Thus, the adaptation led to a facilitation of search performance that was selective for the background texture. Our results are consistent with the hypothesis that adaptation allows observers to more effectively suppress the specific structure of the background, thereby heightening visual salience and search efficiency.
DGEM — A Microarray Gene Expression Database for Primary Human Disease Tissues

Gene expression patterns can reflect gene regulations in human tissues under normal or pathologic conditions. Gene expression profiling data from studies of primary human disease samples are particularly valuable since these studies often span many years in order to collect patient clinical information and achieve a large sample size. Disease-to-Gene Expression Mapper (DGEM) provides a beneficial community resource to access and analyze these data; it currently includes Affymetrix oligonucleotide array datasets for more than 40 human diseases and 1400 samples. The data are normalized to the same scale and stored in a relational database. A statistical-analysis pipeline was implemented to identify genes abnormally expressed in disease tissues or genes whose expressions are associated with clinical parameters such as cancer patient survival. Data-mining results can be queried through a web-based interface at http://dgem.dhcp.iupui.edu/. The query tool enables dynamic generation of graphs and tables that are further linked to major gene and pathway resources that connect the data to relevant biology, including Entrez Gene and Kyoto Encyclopedia of Genes and Genomes (KEGG). In summary, DGEM provides scientists and physicians a valuable tool to study disease mechanisms, to discover potential disease biomarkers for diagnosis and prognosis, and to identify novel gene targets for drug discovery. The source code is freely available for non-profit use, on request to the authors.