cssi/SciSciGPT-SciSciNet huggingface dataset:
Secondary failure of platelet recovery after hematopoietic stem cell transplantation

Abstract After primary recovery of platelet counts after transplantation, there can be a late persistent decline called secondary failure of platelet recovery (SFPR), which may occur although the counts of other cell lineages remain within the normal range. SFPR was defined as a decline of platelet counts below 20,000/microL for 7 consecutive days or requiring transfusion support after achieving sustained platelet counts > or=50,000/microL without transfusions for 7 consecutive days after hematopoietic stem cell transplantation (HSCT). The study population consisted of 2871 consecutive patients receiving transplants from January 1990 to March 1997. After primary recovery of platelet counts, SFPR not due to relapse of the underlying disease was observed in 285 of 1401 (20%) patients undergoing allogeneic transplantation and 36 (8%) of 444 patients undergoing autologous transplantation, with a median time of onset after transplantation at day 63 (range, day 21-156) and day 44 (range, day 24-89), respectively. Concomitant neutropenia was seen in 57 (20%) of 285 patients undergoing allogeneic HSCT and 7 (19%) of 36 patients undergoing autologous HSCT with SFPR. By multivariable analysis, the following were factors significantly associated with SFPR after allogeneic HSCT: a transplant from an unrelated donor; a graft-versus-host disease (GVHD) prophylaxis other than methotrexate and cyclosporine; development of grade 2 through 4 acute GVHD; impaired renal or liver function; conditioning with the combination of busulfan, cyclophosphamide, and total body irradiation; stem cell dose; and infections. Cytomegalovirus infection after engraftment and source of stem cells were the only significant risk factors after autologous HSCT. The hazard rate of death was significantly higher in patients who experienced SFPR (hazard ratio=2.6 for allogeneic HSCT; hazard ratio=2.2 for autologous HSCT). SFPR was associated with serious complications and poor outcome after transplantation. The identification of the characteristics and risk factors for SFPR could improve patient counseling and management and lead to the design of effective treatment strategies. Biol Blood Marrow Transplant 2001;7(3):154-62.
SU‐FF‐T‐157: Different Methods of Organ Equivalent Dose Scoring in Monte Carlo Neutron Dose Calculations

Purpose: In proton therapy,neutrons are generated in treatment head and patient. Monte Carlo simulations are widely used to study secondary neutrons.Neutron quality factors are defined conservatively and do not necessarily take into account that dose might be deposited by secondary particles generated by neutrons, which might have a different quality factor. The purpose of this study was to assess how the organ equivalent neutrondose depends on different scoring methods. Method and Materials: Six voxelized phantoms representing patients of different age have been implemented into our Monte Carlo code. Organdoses,D, were combined with weighting factors to calculate organ equivalent doses,H. Method 1 is based on: H 1 = D pp1 *1.1+D pp2 *2.5+D pp3 *5+H pnw +D ep *1.1+H enw +D other *w R (Dppi, Dep, Dother:D for different protonenergy intervals, D from electrons originating from protons and D from particles other than protons or electrons, respectively; Hpnw , Henw : event‐by‐event wR ‐weighted energydeposition by protons originating from neutrons and by electrons originating from neutrons, respectively; wR : neutron weighting factors weighed by the fluence spectrum of the neutrons entering the organ). Method 2 is based on the products of the wR value and the sum of dosesdeposited by all particles: H 2 = (D pp1 +D pp2 +D pp3 +D pn +D ep +D en +D other )*w R (D pn (D en ) : organdosesdeposited by protons (electrons) originating from neutrons, respectively). Method 3 is a variation of method 1 by replacing the newly proposed ICRP neutron radiation factors by its current definition. Results: We found significant relative differences in organ equivalent dose between methods 1 and 2, i.e. 20–50%. We found an increasing discrepancy with increasing age of the phantom but no dependence on the distance of the organ from the PTV. Of all methods, method 1 gives the highest values of organ equivalent dose.Conclusion: When calculating neutrondoses using Monte Carlo simulations, the organ equivalent dose depends significantly on the applied scoring method.
Fluorescence-based visualization of electro-osmotic flow in microfabricated systems

A recently developed imaging tool is employed to study scalar transport in microfabricated fluidic manifolds. Using the two-color fluorescence-based method to generate molecular fluid flow tracers, we investigate electrokinetic flow through channel geometries commonly encountered in micro-total analytical system research and development.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Revisiting Galison’s ‘Aufbau/Bauhaus’ in light of Neurath’s philosophical projects

Abstract In his article entitled ‘Aufbau/Bauhaus’ and related work, Peter Galison explores the connections between the Vienna Circle and the Dessau Bauhaus. Historically, these groups were related, with members of each group familiar with the ideas of the other. Galison argues that their projects are related as well, through shared political views and methodological approach. The two main figures that connect the Vienna Circle to the Bauhaus—and the figures upon which Galison focuses—are Rudolf Carnap and Otto Neurath. Yet, in our view, the connections that Galison develops do not properly capture the common themes between the Bauhaus and Neurath’s philosophical projects. In this paper, we will examine a few of the historical connections between the Dessau Bauhaus and the Vienna Circle, as well as the philosophical connections that Galison draws between these two groups. By examining in greater depth Neurath’s philosophical commitments, we aim to demonstrate that some of these philosophical connections fail to resonate with Neurath’s projects. And, finally, we develop different connections between Neurath’s projects and the Bauhaus. In our view, these new connections between Neurath and the Dessau Bauhaus are both substantive and philosophically interesting.
Evidence that GHN phase bias does not constitute a framing code

It has been suggested that a triplet repeated pattern found in coding sequences, the G-nonG-N or GHN phase bias, serves a framing function during protein synthesis. To test this idea, the framing characteristics of a highly GHN biased sequence are examined. No effects on reading frame maintenance are observed despite the use of sensitive frameshift assays. Specifically, first the GHN phase is not more accurate than the alternative overlapping phases (i.e., HNG and NGH). Second, ribosomes do not exhibit any significant tendency to slip from the alternative frames into the GHN pahse. In addition, examination of Escherichia coli programmed frameshift sites does not support roles for GHN phase bias in programmed frameshifting. Framing functions for GHN phase bias, if they occur at all, must be extremely limited.
Beneficial effects of nitroprusside administration on left ventricular dysfunction and myocardial ischemia in severe aortic stenosis

Abstract Although surgical therapy is effective for reducing excessive left ventricular (LV) afterload in valvular aortic stenosis (AS), salutary short-term medical treatment has been lacking. Since we have shown LV systolic pressure (SP) is altered concordant with arterial SP in AS by vasopressors, the present study evaluated efficacy of nitroprusside (NP) on LV function, energetics, and perfusion in 15 severe AS patients. NP infusion (average 33 μg/min) proved beneficial in each: LVSP 192 mm Hg was reduced to 164; arterial SP decrement equaled LVSP change; LV end-diastolic pressure 19 mm Hg declined to 10; cardiac index (2.73 L/min/m2) and heart rate were unaltered; total systemic vascular resistance 1433 dsc5 decreased to 1201; elevated LV stroke work index 92 gm·m/m2 was diminished to 74. Simultaneously, LV O2 consumption fell, LV diastolic flow was unchanged, while subendocardial perfusion increased. Thus cautious NP therapy with careful monitoring provided marked reduction of LV afterload and improved LV function, energetics, and coronary flow distribution.
Tonic GABAA receptor-mediated neurotransmission in the dorsal vagal complex regulates intestinal motility in rats

Vagal motor outflow from the dorsal vagal complex is important in the regulation of intestinal motility. The aim of our study was to test the hypothesis that within the dorsal vagal complex, tonic GABA(A)-receptor mediated neurotransmission modulates intestinal motility. The GABA(A) receptor antagonist, bicuculline (methiodide), was microinjected into the dorsal vagal complex, and the effects on small intestinal and colonic motility were investigated. Rats were anesthetized and the mean arterial pressure and heart rate were monitored. Jejunal and colonic motility were measured manometrically, and motility indices were calculated manually. Bicuculline at concentrations of 0.25 or 0.5 mM in 30 nl was microinjected bilaterally into the dorsal vagal complex through stereotaxically placed micropipettes. The injection sites were confirmed histologically using the dye Alcian Blue. Bicuculline (0.5 mM) inhibited spontaneous jejunal motility by 76.3%, colonic motility by 51.7%, mean arterial pressure by 23.3% and heart rate by 27.6%. The lower concentration of bicuculline (0.25 mM) showed no inhibitory effects on intestinal motility but decreased mean arterial blood pressure by 24.1% and heart rate by 13.6%. Bilateral cervical vagotomy attenuated the bicuculline (0.5 mM)-induced inhibition of spontaneous jejunal motility, whereas the bicuculline effect on colonic motility was unaffected. The results of this study show that GABA(A) receptor-mediated neurotransmission in the dorsal vagal complex is involved in autonomic integration of motility of the small intestine and colon. Furthermore, our results indicate that the dorsal vagal complex regulation of jejunal motility involves vagal outflow, whereas vagal pathways do not participate in the bicuculline-induced inhibition of colonic motility.
SPONTANEOUS COHERENCE AND COLLECTIVE MODES IN DOUBLE-LAYER QUANTUM-DOT SYSTEMS

We study the ground state and collective excitations of parabolically confined double-layer quantum-dot systems in a strong magnetic field. We identify parameter regimes where electrons form maximum density droplet states, quantum-dot analogs of the incompressible states of the bulk integer quantum Hall effect. In these regimes the Hartree-Fock approximation and the time-dependent Hartree-Fock approximations can be used to describe the ground state and collective excitations, respectively. We comment on the relationship between edge excitations of dots and edge magnetoplasmon excitations of bulk double-layer systems. {copyright} {ital 1996 The American Physical Society.}
A note on single-processor scheduling with time-dependent execution times

We consider a single-processor scheduling model where the execution time of a task is a decreasing linear function of its starting time. The complexity of the problem of minimizing the number of late tasks remains unknown for a set of tasks with identical due dates. We present an O(n^2)-time dynamic programming algorithm for solving this problem.
Olfactory receptors of the spiny lobster: ATP-sensitive cells with similarities to P2-type purinoceptors of vertebrates

1. A distinct population of ATP-sensitive cells, with response characteristics indicative of P2-type purinoceptors found in internal tissues of vertebrates, was identified among the antennular olfactory cells of the spiny lobster,Panulirus argus. 2. Extracellular recordings from single cells showed that the ATP-sensitive cells had the following properties in common with P2 purinoceptors: a) potency sequence of ATP>ADP>AMP and adenosine; b) broad sensitivity to nucleotide triphosphates including those with modifications in both the purine and ribose moieties; c) stimulated by slowly degradable analogs of ATP, namely,β, γ-imido ATP (AMPPNP),β, γ-methylene ATP (AMPPCP), and α,β-methylene ATP (AMPCPP). 3. The activity sequence of the ATP-sensitive cells for nucleotides and related substances was ATP≥2′-deoxyATP>GTP>CTP≥XTP≥ITP> 8-bromo-ATP=ADP, with pyrophosphate, AMP, and tripolyphosphate being virtually inactive. 4. The potency sequence for the slowly degradable analogs was AMPPNP>ATP = AMPPCP> AMPCPP. 5. Differences in structure-activity relationships, response duration, and response magnitude clearly distinguished the ATP-sensitive cells from another type of olfactory purinoceptor, the AMP-sensitive cells, also occurring in the antennules of the lobster. 6. Comparisons between the ATP-sensitive chemoreceptors of the lobster and of certain insects revealed similarities in the activity sequence of ATP, ADP, AMP, and certain other nucleotides. However differences existed in the relative potencies of ATP, AMPPNP, and AMPPCP, and in the relative inactivity of inorganic pyrophosphate in the lobster. 7. The findings of this study lend additional credence to the earlier hypothesis that receptors for transmitters and modulators existing in internal tissues may have evolved from external chemoreceptors of primitive unicellular organisms.
Impact of dominant breaking waves on air-sea momentum exchange and boundary layer turbulence at high winds

AbstractLarge-eddy simulation (LES) is used to investigate how dominant breaking waves in the ocean under hurricane-force winds affect the drag and near-surface airflow turbulence. The LES explicitly resolves the wake turbulence produced by dominant-scale breakers. Effects of unresolved roughness such as short breakers, nonbreaking waves, and sea foam are modeled as the subgrid-scale drag. Compared to the laboratory conditions previously studied using the same method, dominant-scale breakers in open-ocean conditions are less frequent, and the subgrid-scale drag is more significant. Nevertheless, dominant-scale breakers are more fully exposed to high winds and produce more intense wakes individually. As a result, they support a large portion of the total drag and significantly influence the turbulence for many ocean conditions that are likely to occur. The intense wake turbulence is characterized by flow separation, upward bursts of wind, and upward flux of the turbulent kinetic energy (TKE), all of which ...
Process Planning for Multi-Directional Laser-Based Direct Metal Deposition:

AbstractLaser-based direct metal deposition has demonstrated the capability to deposit metal along multiple directions. Suitable control of parameters, namely, the metal-powder feed rate, the traverse speed, and the laser power allow fabrication of a desired shape for a large family of parts. The capability to deposit material along multiple directions eliminates the requirement for support structures. However, accessing the point of deposition and manipulating the direction of deposition require a coordinated control of two kinematical systems; one is related to the deposition platform, whereas the other is related to the deposition head. The identification of the key challenges, a mathematical basis of the process, possible solutions, the subsequent process planning, and experimental results are the subjects of this article.
Silica Based 3,5-Dinitrobenzoyl (Dnb) Reagent for Off-Line Derivatization of Amine Nucleophiles in HPLC

Abstract We describe here a new silica based derivatization reagent, containing the 3,5-dinitrobenzoyl tag, for solid phase derivatization of amines. It can be used for the off-line derivatization of primary and secondary amines. the amide derivatives can be easily detected under conventional UV detection modes. the entire synthetic method, structural characterization, and optimization of derivatization conditions of this solid phase derivatization reagent are described, Also, the reagent was tested in the on-line, pre-column derivatization mode for reversed phase HPLC, as well as for histamine analysis in fish samples
A Dimensionless Graceful Degradation Metric for Quantifying Resilience

Many self-* properties are variations on the same theme: resilience of a system to changes in itself or the conditions under which it operates. Quantifying resilience is difficult, however: there are no metrics of resilience that are readily comparable across systems, and the space of possible changes is typically prohibitively large. To address this problem, I propose a quantitative measure of graceful degradation that is independent of the units, scales, and number of system parameters. Although this metric is typically intractable to compute precisely, it can be approximated by perturbation surveys, and the quality of approximation is likely to be improved by a random perturbation approach based on recent advances in manifold learning.
Myelin Gene Regulatory Factor Is a Critical Transcriptional Regulator Required for CNS Myelination

The transcriptional control of CNS myelin gene expression is poorly understood. Here we identify gene model 98, which we have named myelin gene regulatory factor (MRF), as a transcriptional regulator required for CNS myelination. Within the CNS, MRF is specifically expressed by postmitotic oligodendrocytes. MRF is a nuclear protein containing an evolutionarily conserved DNA binding domain homologous to a yeast transcription factor. Knockdown of MRF in oligodendrocytes by RNA interference prevents expression of most CNS myelin genes; conversely, overexpression of MRF within cultured oligodendrocyte progenitors or the chick spinal cord promotes expression of myelin genes. In mice lacking MRF within the oligodendrocyte lineage, premyelinating oligodendrocytes are generated but display severe deficits in myelin gene expression and fail to myelinate. These mice display severe neurological abnormalities and die because of seizures during the third postnatal week. These findings establish MRF as a critical transcriptional regulator essential for oligodendrocyte maturation and CNS myelination.
Jeffrey Brace in Barbados: Slavery, Interracial Relationships, and the Emergence of a Global Economy

On a sunny afternoon in 1758 a sixteen‐year‐old boy named Boyrereau Brinch and a group of his friends ascended the banks of the Niger River after several hours of swimming and water sports. On shor...
Hunting Causes and Using Them: Approaches in Philosophy and Economics. Nancy Cartwright

This collection of 13 articles by Nancy Cartwright takes a simple observation as its organizing principle: The fundamental questions about causal claims bear an intimate relation to one another not...
DO NUCLEI FLOW AT HIGH-ENERGIES?

Abstract Nuclear flow patterns for E lab = 250 MeV/nucleon are generated using the cascade code of Cugnon et al. and analyzed in terms of a kinetic flow tensor. The effect of increasing the nucleon-nucleon cross section and the difference between repulsive and stochastic scattering styles are studied. A flow diagram is proposed to aid the experimental search for such flow patterns.
Co-regulation of the mixed-function oxidation of p-nitroanisole and glucuronidation of p-nitrophenol in the perfused rat liver by carbohydrate reserves.

Maximal rates of mixed-function oxidation of p-nitroanisole and the glucuronidation of p-nitrophenol in perfused livers from phenobarbital-treated rats varied directly with the nutritional state of the rat (i.e., fasted < fed < fasted-refed). Rates correlated with intracellular concentrations of NADPH, UDP-glucuronic acid, and glycogen but not with amounts of cytochrome P-450 or glucuronyltransferase activity. These data support the hypothesis that mixed-function oxidation and glucuronidation are coregulated in intact cells by carbohydrate-dependent cofactor synthesis.
Ethnic disparities in conditional survival of patients with non-small cell lung cancer.

Purpose: Conditional survival (CS) is an accurate estimate of survival probability for patients who have already survived at least 1 year after diagnosis. The purpose of this study was to determine whether ethnicity plays a role in 5-year CS rates for patients with non-small cell lung cancer (NSCLC). Materials and Methods: Using the Surveillance, Epidemiology, and End Results database, we analyzed 96,480 patients with NSCLC diagnosed between 1988 and 1995. Patients were divided into five ethnic groups: White (non-Hispanic), Hispanic, African American, Asian/Pacific Islander, and Native American/Alaskan. Using the life table method, we computed observed 5-year CS rates for patients who had already survived up to 5 years after diagnosis. Results were analyzed by stage, age, sex, and histology. Results: In general, 5-year CS rates increase for all ethnicities as time from diagnosis increases, but African Americans continued to have lower CS rates compared with other ethnic groups, even up to 5 years from diagnosis. When analyzed by stage, Hispanics with stage IV disease showed the greatest improvement in CS rate, increasing to 73% at 5 years from diagnosis. Among patients older than 70 years, African Americans had the lowest CS at 5 years—only 28%, compared with 40% to 47% for other groups. When analyzed by histology, Hispanics with large cell carcinoma had the worst CS rate (35% at 5 years). Conclusion: For patients with NSCLC surviving a period of time after diagnosis, 5-year CS rates vary by ethnicity. CS can provide accurate prognostic information for patients with NSCLC who have already survived several years after diagnosis.
Imperial Geography and the Medieval Peutinger Map

The Peutinger map is an extraordinary world map drawn c.1200 and long considered a copy of a Roman road map made for late antique travellers. This paper presents arguments against these assumptions and concludes that the lost original was more likely to be a Carolingian display map. Ninth‐century scribes had the expertise and resources necessary for creating an antiquarian work based on Roman itinerary lists, while Carolingian rulers had ample motivation for commissioning a map to display their Roman imperial ambitions.
Evaluation of estrogenic activity from a municipal wastewater treatment plant with predominantly domestic input

Abstract The purpose of this study was to survey estrogenic releases from two primarily domestic wastewater treatment plants over three seasons (1996–1999). Mature male channel catfish were maintained at two sites within each WWTP and a reference site for 21 days. Estrogenic activity of effluent was assessed by the Yeast Estrogen Screen (YES) assay (in 1999) and the expression of the female egg yolk precursor protein, vitellogenin (Vtg) in caged male channel catfish (1996–1998). Serum Vtg of animals exposed at WWTP-A was induced 220% above reference values in the Fall of 1996 and 480% in Spring of 1997. In animals exposed to effluent of WWTP-B, serum Vtg was elevated 370% in Spring of 1997 and 480% in Fall of 1997 relative to fish held in a reference location. Serum 17-β-estradiol (E2) levels were also significantly elevated 13 and 16-fold in the Fall 1997 and Summer 1998 in the fish exposed to WWTP-A effluent. A 13.5-fold increase in serum E2 was observed in fish exposed to WWTP-B during Fall 1997. Utilizing an E2 concentration-Vtg response curve generated in the laboratory, effluent from both plants (in 1997 and 1998) had estrogen equivalent values ranging from 23 to 123 ng/l E2 equivalents. These values were comparable with YES values obtained from 1999, which indicated the presence of 21 to 147 ng/l E2 equivalents. E2 was responsible for 3 (fall) to 100% (summer) of the YES activity. Glucuronides of E2 were also observed in the treated effluent. These studies indicate that variable estrogenic activity is present in municipal wastewater resulting from domestic activities and that this activity may be significantly altered by environmental factors.
Site of action of colchicine on RNA release from liver nuclei

Summary Colchicine inhibition of messenger RNA release from rat liver nuclei has been analyzed in a cell-free system, which supports the processing and transport of functional RNA. The degree of inhibition is porportional to the colchicine concentration above 300 μM. The site of action is not microtubular elements associated with the nuclei, since some colchicine analogs containing a trimethoxy-benzene ring do not disrupt microtubules, but still inhibit RNA transport. Furthermore, the Vinca alkaloids, which like colchicine disrupt microtubules, do not inhibit messenger RNA transport. From an assessment of its effect on nuclear RNA metabolism, it is concluded that colchicine inhibits RNA release by inhibiting RNA transport rather than RNA processing. This effect may be due to the specific binding of colchicine to the nuclear membrane.
Male Common Loons Signal Greater Aggressive Motivation By Lengthening Territorial Yodels

Abstract We examined two critical predictions of the hypothesis that male Common Loons (Gavia immer) communicate greater aggressive motivation by increasing the number of repeat syllables within their territorial yodels. We observed (from >3,500 hrs of field observations of 58 males) the probability that territorial interactions escalated from territorial flyovers by intruders to stereotyped ‘social gatherings’ to escalated fights between residents and intruders was positively correlated to the number of repeat syllables given by individually-banded males. Males yodeling during these escalated contests often assumed the upright ‘vulture’ posture rather than the usual ‘crouch’ posture, reflecting an escalated aggressive motivational state. Territorial pairs responded sooner and with more threat and alarm vocalizations to playback yodels that contained more repeat phrases. This reflected a greater willingness to attack by residents to perceived intrusions by males of higher aggressive motivational state. Ou...
A snapshot analysis of age distributions of fishes in urban and forested Virginia streams

An understanding of the spatial variation in the population structure of lotic fishes is vital to their conservation. Population level approaches may be more suitable than community level approaches for identifying stream fish response to urbanization. Lithophilic (clean mineral substrate) spawners are disproportionally affected by common habitat disturbances, and are thus expected to exhibit great demographic variation along gradients of disturbance. We related age distributions of six stream fishes, exhibiting four different types of lithophily (speleophily, saucer-pit nesting, gravel mound nesting, and simple broadcasting/nest association), to land cover and instream habitat variables. Fishes were collected from 18 urban or forested reaches of three 2nd-4th Strahler-order tributaries of the New River, Virginia. Individuals were assigned to age classes based on length-frequency histograms verified by sagittal otolith analysis. Chi-square tests and multiple polytomous logistic regression were used to relate population structure to land cover types and associated instream habitat variables. Age distributions of broadcast lithophils were unbalanced (containing relatively higher proportions of adults than juveniles) in urban reaches, whereas those of nest-constructing spawners were always balanced. Mixed responses were observed between the two speleophils. Differences in the directional effect of urbanization on population structure may be attributable to species’ tendency to: a) modify available substrate, b) to provide parental care to their brood, and c) life-history traits other than spawning mode (e.g. age at maturation). Although nest association may confer greater reproductive success to participants, this activity was not beneficial enough to give associates balanced age distributions in urban reaches. These results suggest that source-sink dynamics may operate to prevent populations of various fishes in urban reaches from being extirpated. Future research should focus on differences in population dynamics of stream fishes among land cover types.
Necrotizing fasciitis in children: prompt recognition and aggressive therapy improve survival

Abstract Necrotizing fasciitis (NF) is a bacterial infection of the soft tissues with a fulminant course and a high mortality rate. The authors performed a review to define the diagnosis, bacteriology, and management of NF in the pediatric population. This report of 20 cases treated over 18 years represents the largest reported pediatric experience. These infections were attributable to secondary infection of varicella lesions (5), omphalitis (4), extremity lesions (4), perineal infections (3), head and neck lesions (2), inguinal herniorrhapy (1), and breast abscess (1). Nineteen of the 20 children were healthy, without chronic disease or immunosuppression. All patients presented with an altered sensorium and signs of systemic toxicity. Fever (40%), tachycardia (70%), and abnormal white blood cell count (50%) were not uniformly present. There was marked tissue edema in all patients, with a characteristic peau d'orange appearance in 18. Seven infections were caused by streptococcus; the remainder were polymicrobial, involving multiple aerobes and anaerobes. Initial gram stain was of limited utility; in 14 of 19 cases the result was negative or showed only one of many organisms present. Fifteen patients survived and five died. All survivors underwent aggressive surgical debridement within 3 hours of admission. The survivors required of a mean of 3.8 operations. Fascial excision of up to 35% of total body surface area was required. One patient required amputation two had colostomies, and six required extensive skin grafting for reconstruction. All five patients who died had delayed initial management. Conclusion: NF is a serious cause of death in previously healthy children. The diagnosis should be considered in the presence of any soft tissue infection presenting with signs of toxicity and marked wound edema, even in the absence of fever or abnormal white blood cell count. Immediate surgical debridement and coverage with penicillin, an aminoglycoside, and metronidazole are essential. Subsequent changes in antibiotics should be based on culture data because gram stain results are not reliable. More than one operation is required in almost all cases.
Mechanism of iron induction of ferritin synthesis.

Summary Polyribosomes and mRNAs from normal and iron-treated rats were isolated, and their relative capacities for apoferritin synthesis in a cell-free system were measured. In vitro synthesis of apoferritin was 2-fold greater when polyribosomes or mRNA from iron-treated rats was used, whereas total protein synthesis was unchanged. This finding shows that one mechanism by which iron administration stimulates apoferritin synthesis is by increasing the amount of apoferritin mRNA in polyribosomes.
Analytical representations for simple and composite polytropes and their moments of inertia

Abstract Polytropes are widely applied in astrophysics. To facilitate their use, we derive analytical formulae for the moment of inertia as a function of polytropic index. We also provide 1- and 3-parameter equations that replicate the density variations in polytropic bodies to varying degrees of accuracy, determined by numerical calculations and analytical results for polytropic indices between 0 and 5. As an example, we construct a composite polytrope, suitable for gas giants, exoplanets, or tiny sub-solar dwarfs, wherein an inner sphere is modeled by constant density, which represents the density jump associated with production of a relatively incompressible solid, and an outer envelope is modeled as having a polytropic index near 2.5, which corresponds to a diatomic gas. Envelope sizes are constrained by the moment of inertia.
Effects of systematic variation of amino acid sequence on the mechanical properties of a self-assembling, oligopeptide biomaterial

In order to elucidate design principles for biocompatible materials that can be created by in situ transformation from self-assembling oligopeptides, we investigate a class of oligopeptides that can self-assemble in salt solutions to form three-dimensional matrices. This class of peptides possesses a repeated sequence of amino acid residues with the type: hydrophobic/negatively-charged/hydrophobic/positively-charged. We systematically vary three chief aspects of this sequence type: (1) the hydrophobic side chains; (2) the charged side chains; and (3) the number of repeats. Each of these has been previously shown to influence the self-assembly properties of these materials. Employing a rheometric assay we measure the shear modulus of gels created from variants of each of these aspects. First, we observe order-of-magnitude changes in shear moduli when we vary oligopeptide length, with biphasic dependence on length. This result may be due to competition between, in short oligopeptides, additional repeats either increasing the diameter of the filaments or increasing the area of interaction between individual molecules and, in large oligopeptides, additional repeats allowing the oligopeptides to fold back upon themselves and decrease their effective length. Second, no statistically significant difference is observed among the hydrophobic variants, suggesting that hydrophobicity and steric overlap are unlikely to play a significant role in filament mechanical properties. Finally, in variation of the charged side chains we observe a small difference in the shear moduli that, if significant, may mean that decreasing the energetic penalty for dehydrating the charged side chains can lead to a stiffer matrix. Overall, we demonstrate that it is possible to achieve order-of-magnitude changes in shear modulus by simple variations of oligopeptide length, while the residue substitutions affect only self-assembly properties. Thus, diverse aspects of these molecules can be designed rationally to yield desirable materials properties of different types.
The Case for Paying College Athletes

Big-time commercialized intercollegiate athletics has attracted considerable attention in recent years. Popularity of this uniquely American activity, measured by attendance, television ratings, or team revenues, has never been higher. At the same time, however, several high-profile scandals exposing unseemly behavior on the part of players, coaches, and even respected higher education institutions—as well as questions about the distribution of the enormous revenues pouring into university athletic departments—have marred the image of these college football and men's basketball programs. Currently there are several legal challenges to the National Collegiate Athletic Association (NCAA) and its member institutions that may change dramatically and permanently the arrangements between the NCAA cartel, its member colleges and universities, and the "student-athletes" who play on the teams. These challenges all focus on the NCAA's collective fixing of players' wages. We describe this peculiar "industry," detailing the numerous market imperfections in both output and labor markets, the demand for and supply of college athlete labor, and possible alternative arrangements in the college athlete labor market, including the ramifications of compensating players beyond the tuition, room, board, books, and fees that some current players already receive as grants-in-aid.
Breathing Words Slowly: Creative Writing and Counselor Self-Care—The Writing Workout

Professional counselors work daily with compassion and connection, yet must also manage trauma and pain. Clients' stories of loneliness, fear, abuse, and anger frequently fill the landscape of a counselor's work. Counselors may experience burnout, compassion fatigue, and vicarious trauma by failing to recognize and adequately address the negative emotions and thoughts they may unintentionally carry from their work. By prioritizing and attending to self-awareness and self-care, counselors maintain their clinical efficacy and personal well-being. This article presents creative writing as a valuable self-care technique, offers a writing structure for counselors to use, and includes two brief illustrations of creative writing that promote self-care.
Molecular Characterization of an Arachidonic Acid Epoxygenase in Rat Brain Astrocytes

Background and Purpose Brain parenchymal tissue metabolizes arachidonic acid (AA) via the cytochrome P450 (P450) epoxygenase to epoxyeicosatrienoic acids (EETs). EETs dilate cerebral arterioles and enhance K+ current in vascular smooth muscle cells from large cerebral arteries. Because of the close association between astrocytes and the cerebral microcirculation, we hypothesized that brain epoxygenase activity originates from astrocytes. This study was designed to identify and localize an AA epoxygenase in rat brain astrocytes. We also tested the effect of EETs on whole-cell K+ current in rat cerebral microvascular smooth muscle cells. Methods A functional assay was used to demonstrate endogenous epoxygenase activity of intact astrocytes in culture. Oligonucleotide primers derived from the sequence of a known hepatic epoxygenase, P450 2C11, were used in reverse transcription/polymerase chain reaction of RNA isolated from cultured rat astrocytes. The appropriate size reverse transcription/polymerase chain ...
Antioxidant responses to chronic hypoxia in the rat cerebellum and pons

Obstructive sleep apnea (OSA) is characterized by chronic intermittent hypoxia (CIH) and sleep fragmentation and deprivation. Exposure to CIH results in oxidative stress in the cortex, hippocampus and basal forebrain of rats and mice. We show that sustained and intermittent hypoxia induces antioxidant responses, an indicator of oxidative stress, in the rat cerebellum and pons. Increased glutathione reductase (GR) activity and thiobarbituric acid reactive substance (TBARS) levels were observed in the pons and cerebellum of rats exposed to CIH or chronic sustained hypoxia (CSH) compared with room air (RA) controls. Exposure to CIH or CSH increased GR activity in the pons, while exposure to CSH increased the level of TBARS in the cerebellum. The level of TBARS was increased to a greater extent after exposure to CSH than to CIH in the cerebellum and pons. Increased superoxide dismutase activity (SOD) and decreased total glutathione (GSHt) levels were observed after exposure to CIH compared with CSH only in the pons. We have previously shown that prolonged sleep deprivation decreased SOD activity in the rat hippocampus and brainstem, without affecting the cerebellum, cortex or hypothalamus. We therefore conclude that sleep deprivation and hypoxia differentially affect antioxidant responses in different brain regions.
Control of hyperactivation in sperm

BACKGROUND: Sperm hyperactivation is critical to fertilization, because it is required for penetration of the zona pellucida. Hyperactivation may also facilitate release of sperm from the oviductal storage reservoir and may propel sperm through mucus in the oviductal lumen and the matrix of the cumulus oophorus. Hyperactivation is characterized by high amplitude, asymmetrical flagellar bending. METHODS: This is a review of the original literature on the mechanisms that regulate hyperactivation, including physiological factors and signaling pathways. RESULTS: Computer-assisted semen analysis systems can be used to identify hyperactivated sperm by setting minimum thresholds for curvilinear velocity (VSL) and lateral head movement and a maximum threshold for path linearity. Hyperactivation is triggered by a rise in flagellar Ca(2+) resulting from influx primarily through plasma membrane CatSper channels and possibly also by release of Ca(2+) from a store in the redundant nuclear envelope. It requires increased pH and ATP production. The physiological signals that trigger the rise in Ca(2+) remain elusive, but there is evidence that the increased Ca(2+) acts through a calmodulin/calmodulin kinase pathway. Hyperactivation is considered part of the capacitation process; however, the regulatory pathway that triggers hyperactivation can operate independently from that which prepares sperm to undergo the acrosome reaction. Hyperactivation may be modulated by chemotactic signals to turn sperm toward the oocyte. CONCLUSIONS: Little is known about exactly what triggers hyperactivation in human sperm. This information could enable clinicians to develop reliable fertility assays to assess normal hyperactivation in human sperm samples.
Overcoming a Learning Bottleneck: Inquiry Professional Development for Secondary Science Teachers

This paper examines the summer component of a year-long professional development program. The program was developed based on recent models of effective professional development that indicate that teachers should guide the direction and focus of the professional development program. Specific activities in the summer program were adapted from a long-running, successful program for university faculty development. In this study we explore the conceptions of inquiry teachers developed during the program, as well as the products teachers created. The discrepancies between program goals and the teachers’ products and conceptions are described and reasons for these differences explored. The results suggest that engaging teachers in identifying key issues in their own professional development is an effective strategy.
An adaptive estimation of MAVE

Minimum average variance estimation (MAVE, Xia et al. (2002) [29]) is an effective dimension reduction method. It requires no strong probabilistic assumptions on the predictors, and can consistently estimate the central mean subspace. It is applicable to a wide range of models, including time series. However, the least squares criterion used in MAVE will lose its efficiency when the error is not normally distributed. In this article, we propose an adaptive MAVE which can be adaptive to different error distributions. We show that the proposed estimate has the same convergence rate as the original MAVE. An EM algorithm is proposed to implement the new adaptive MAVE. Using both simulation studies and a real data analysis, we demonstrate the superior finite sample performance of the proposed approach over the existing least squares based MAVE when the error distribution is non-normal and the comparable performance when the error is normal.
Species dynamics in disturbed landscapes : when does a shifting habitat mosaic enhance connectivity?

Although landscape ecology emphasizes the effects of spatial pattern on ecological processes, most neutral models of species–habitat relationships have treated habitat as a static constraint. Do the working hypotheses derived from these models extend to real landscapes where disturbances create a shifting mosaic? A spatial landscape simulator incorporating vegetation dynamics and a metapopulation model was used to compare species in static and dynamic landscapes with identical habitat amounts and spatial patterns. The main drivers of vegetation dynamics were stand-replacing disturbances, followed by gradual change from early-successional to old-growth habitats. Species dynamics were based on a simple occupancy model, with dispersal simulated as a random walk. As the proportion of available habitat (p) decreased from 1.0, species occupancy generally declined more rapidly and reached extinction at higher habitat levels in dynamic than in static landscapes. However, habitat occupancy was sometimes actually higher in dynamic landscapes than in static landscapes with similar habitat amounts and patterns. This effect was most pronounced at intermediate amounts of habitat (p = 0.3−0.6) for mobile species that had high colonization rates, but were unable to cross non-habitat patches. Differences between static and dynamic landscapes were contingent upon the initial metapopulation size and the shapes of disturbances and the resulting habitat patterns. Overall, the results demonstrate that dispersal-limited species exhibit more pronounced critical behavior in dynamic landscapes than is predicted by simple neutral models based on static landscapes. Thus, caution should be exercised in extending generalizations derived from static landscape models to disturbance-driven landscape mosaics.
Enabling independent learning of programming concepts through programming completion puzzles

Many novice programming environments use puzzle-like approaches to help novice programmers acquire new programming skills independently. Yet, little is known about 1) how puzzles can support effective learning of programming skills and 2) how learning programming using a puzzle-based approach compares to more a traditional tutorial style approach. We conducted a pair of studies to explore these two questions. First, we report lessons learned on the design of programming completion puzzles, their interface within a novice programming environment, and the design of a puzzle curriculum drawn from our first, formative study. We then report on a second study that compared the learning effectiveness of programming puzzles and tutorials. The results suggest that puzzles are a promising approach for introducing programming concepts within novice programming environments. Puzzle users performed 26% better on transfer tasks compared to tutorial users, while taking 23% less time to complete the learning materials.
Assuming Silence in Arbitration

This Article provides a short summary of the distinctions between privacy and confidentiality in domestic arbitration pursuant to non-public parties’ private agreements, and seeks to spark discussion of transparency reforms that respond to effects of these distinctions in that context. It explains that such arbitration is generally private in that it is a closed process, but it is not confidential to the extent information revealed during the process may become public. This has caused confusion regarding the arbitration process that may lead parties to accept arbitration agreements without contracting for confidentiality, which may disproportionately harm individuals who assume that their personal information revealed in arbitration will remain secret. At the same time, companies may use confidentiality provisions, along with arbitration’s privacy, to shield information regarding their legal violations that may affect public interests.
Similarity of wh-Phrases and Acceptability Variation in wh-Islands.

In wh-questions that form a syntactic dependency between the fronted wh-phrase and its thematic position, acceptability is severely degraded when the dependency crosses another wh-phrase. It is well known that the acceptability degradation in wh-island violation ameliorates in certain contexts, but the source of this variation remains poorly understood. In the syntax literature, an influential theory – Featural Relativized Minimality – has argued that the wh-island effect is modulated exclusively by the distinctness of morpho-syntactic features in the two wh-phrases, but psycholinguistic theories of memory encoding and retrieval mechanisms predict that semantic properties of wh-phrases should also contribute to wh-island amelioration. We report four acceptability judgment experiments that systematically investigate the role of morpho-syntactic and semantic features in wh-island violations. The results indicate that the distribution of wh-island amelioration is best explained by an account that incorporates the distinctness of morpho-syntactic features as well as the semantic denotation of the wh-phrases. We argue that an integration of syntactic theories and perspectives from psycholinguistics can enrich our understanding of acceptability variation in wh-dependencies.