cssi/SciSciGPT-SciSciNet huggingface dataset:
High precision chi-square and normal curve integration

The routine discussed in this paper determines chi­ square and normal curve probabilities in a manner simi­ lar to a technique introduced by Wood and Wood (1985). Their program integrates the t density function to provide two-tailed t probabilities with five decimal place accuracy, up to a maximum of 115 df (n). The level of accuracy in their technique is achieved via an algorithm of Simp­ son's rule. The handling ofthe large maximum n without computer overflow is achieved by recognizing that, be­ cause n is integral in t, chi-square, and F, J'(n/Z) is a fac­ torial process. Because f(t) contains r[(n+ 1)/2]/r(n/2), common factorial factors are divided out before multipli­ cation, thus reducing the magnitude of the two products and preventing overflow until n exceeds 115. The routine presented here (see Appendix) achieves ac­ curate results via application of the same swift algorithm of Simpson's rule in which the chi-square and normal den­ sity functions are divided into tiny segments. The areas are then determined and summed (Anton, 1981). Ac­ curacy is provided to a minimum of five decimal places. The range of numerical integration is not a problem with the normal curve, because this routine accurately finds any specified area bounded by Z = -6 and Z = 6, and having a probability within six decimal places. The range of integration becomes a problem with chi-square bounded by 0 and 00, and for which It = n (Beyer, 1979, p. 522). Nevertheless, with one exception the program exactly evaluates all chi-squares having probabilities from .000001 to .999998 for 1 :5 n :5 34. Where n = 3, five place accuracy is maintained. The Simpson's rule algorithm evaluates a standard ver­ sion of chi-square (Beyer, 1979, p. 522) that is algebra­ ically manipulated for programming purposes into the fol­ lowing form: 1
Electromagnetic acceleration of the Belousov–Zhabotinski reaction

Abstract Acceleration of the Belousov–Zhabotinski (BZ) reaction, in stirred homogeneous solutions, by low frequency electromagnetic (EM) fields has provided new insights into EM interaction mechanisms. The acceleration varies inversely with the basal reaction rate, indicating that the applied magnetic field and the intrinsic chemical driving forces affect the same electron transfer reaction. The amplitude and frequency dependence of the EM field interactions are also consistent with interaction during electron transfer. A mechanism based on interaction with moving electrons offers a way of explaining the ability of EM fields to stimulate gene expression, in particular the stress response, since electrons have been shown to move in DNA.
Identification of Pseudomonas plasmids able to suppress the lysogeny-establishment-deficiency (Les−) phenotype

A suppressor of the mutations which inhibit the establishment of lysogeny in Pseudomonas aeruginosa has been found to be encoded by P. aeruginosa plasmids of four separate incompatibility groups. The wide distribution of this phenotype (designated Sly for suppressor of lysogeny establishment deficiency) indicates that these plasmids are able to enhance or replace host functions involved in the stable establishment of extrachromosomal DNA.
Neighborhood-Level Correlates of Consistent Condom Use among Men Who have Sex with Men: A Multi-Level Analysis

There is growing evidence that the neighborhood environment influences sexual behavior and related outcomes, but little work has focused specifically on men who have sex with men (MSM). Using interview data from a probability sample of 385 young MSM living in New York City, recruited at public venues in 1999 and 2000 as part of the Young Men’s Survey-New York City, and data on neighborhood characteristics obtained from the U.S. Census 2000, we conducted multi-level analyses of the associations between neighborhood-level characteristics and consistent condom use during anal intercourse, while controlling for individual-level sociodemographic and other factors. After adjusting for individual-level factors, neighborhood-level gay presence remained significantly and positively associated with consistent condom use during anal intercourse. This finding suggests that neighborhoods with a significant gay presence may have norms that act to discourage high risk sexual activity.
Detecting gas hydrate behavior in crude oil using NMR.

Because of the associated experimental difficulties, natural gas hydrate behavior in black oil is poorly understood despite its grave importance in deep-water flow assurance. Since the hydrate cannot be visually observed in black oil, traditional methods often rely on gas pressure changes to monitor hydrate formation and dissociation. Because gases have to diffuse through the liquid phase for hydrate behavior to create pressure responses, the complication of gas mass transfer is involved and hydrate behavior is only indirectly observed. This pressure monitoring technique encounters difficulties when the oil phase is too viscous, the amount of water is too small, or the gas phase is absent. In this work we employ proton nuclear magnetic resonance (NMR) spectroscopy to observe directly the liquid-to-solid conversion of the water component in black oil emulsions. The technique relies on two facts. The first, well-known, is that water becomes essentially invisible to liquid state NMR as it becomes immobile, a...
Experimental studies of hydrogen on boron nitride: I. Adsorption isotherms of HD

We report the results of measurements of adsorption isotherms of deuterium hydride (HD) adsorbed onto boron nitride. From this data we derive both the two-dimensional critical point temperatures (using Larher's method) and the heat of adsorption for the first few layers of this system. These results are compared with similar measurements of HD adsorbed onto graphite and MgO. While substantial substeps within some adlayer steps are evident in the adsorption isotherms of HD on graphite and MgO and have been shown to indicate a two-dimensional liquid-solid transition within the layer, no substep is evident at the level of one percent of a step level for HD adsorbed onto BN.
A Viscoelastic Constitutive Model for Determining In-Situ Stress Magnitudes From Anelastic Strain Recovery of Core (includes associated papers 19042 and 19892 )

A three-dimensional viscoelastic model is developed to describe the anelastic-strain-recovery (ASR) process. Measured ASR data are curve-fit to the model by a least-squares algorithm, and viscoelastic material properties are calculated. The stress state at depth can then be determined given some additional information. Examples and comparisons with measured stresses are given.
Minimally Invasive Approaches to Localized Prostate Carcinoma

Prostate cancer is an increasing medical problem. Radical prostatectomy and radiation therapy are effective treatments, but have the risk of significant morbidity. Clinicians have strived to develop new modalities of treatment that can maintain the excellent treatment outcomes of radical prostatectomy, but diminish the morbidity. Improved instrumentation, optics, and robotic technology have allowed the application of laparoscopic techniques to radical prostatectomy. Patients can have less blood loss and expect more rapid recovery. Intermediate oncologic outcomes appear similar to radical prostatectomy with good functional results. Cryotherapy and HIFU are tissue ablative approaches rather than extirpative approaches to prostate cancer treatment. They attempt to use nonsurgical methods to treat prostate cancer with the hope of providing oncologic control comparable to surgery and radiation while minimizing morbidity.
Span of apprehension in hyperactive boys.

The spans of apprehension of hyperactive and normal boys were compared with a forced-choice letter-recognition task developed by Estes (1965). This task provides an estimate of the span which is relatively insensitive to either memory or motivational influences. The span size was the same for both groups when visual “noise” was absent. In the presence of noise, span size for the hyperactive boys decreased. Moreover, as the number of noise letters increased, the reduction in span size observed for the hyperactive boys increased. It is argued that this increasing reduction in span size represents a true deficit in attention.
Use of multipoint algorithms and continuation methods in the solution of distillation problems

Abstract The use of multipoint algorithms combined with continuation methods for the solution of difficult steady-state distillation problems is illustrated. The characteristics of the different combinations of methods are presented and compared by solving a variety of distillation problems. The associated problem of multiple solutions is presented and a method for solving problems of this type is proposed and demonstrated.
Curcumin Supplementation Lowers TNF-α, IL-6, IL-8, and MCP-1 Secretion in High Glucose-Treated Cultured Monocytes and Blood Levels of TNF-α, IL-6, MCP-1, Glucose, and Glycosylated Hemoglobin in Diabetic Rats

This study examined the hypothesis that curcumin supplementation decreases blood levels of IL-6, MCP-1, TNF-alpha, hyperglycemia, and oxidative stress by using a cell-culture model and a diabetic rat model. U937 monocytes were cultured with control (7 mM) and high glucose (35 mM) in the absence or presence of curcumin (0.01-1 microM) at 37 degrees C for 24 h. Diabetes was induced in Sprague-Dawley rats by injection of streptozotocin (STZ) (i.p., 65 mg/kg BW). Control buffer, olive oil, or curcumin (100 mg/kg BW) supplementation was administered by gavage daily for 7 weeks. Blood was collected by heart puncture with light anesthesia. Results show that the effect of high glucose on lipid peroxidation, IL-6, IL-8, MCP-1, and TNF-alpha secretion was inhibited by curcumin in cultured monocytes. In the rat model, diabetes caused a significant increase in blood levels of IL-6, MCP-1, TNF-alpha, glucose, HbA(1), and oxidative stress, which was significantly decreased in curcumin-supplemented rats. Thus, curcumin can decrease markers of vascular inflammation and oxidative stress levels in both a cell-culture model and in the blood of diabetic rats. This suggests that curcumin supplementation can reduce glycemia and the risk of vascular inflammation in diabetes.
Levels of predation and genetically based anti-predator behaviour in the spider, Agelenopsis aperta

Abstract Two populations of the spider, Agelenopsis aperta, experience markedly different levels of avian predation. Although there is no measurable level of avian predation on this species inhabiting a grassland habitat, estimated bird predation on A. aperta in a riparian (woodland) habitat rangesfrom 15 to 86% of the local population per week. Population variability in anti-predator behaviour was tested in an experiment using large amplitude vibrations in the web to simulate a predator. Individuals from the respective populations were tested at their web-sites in the field and second-generation individuals reared in the laboratory were tested in the laboratory for their responses to this stimulus. In both the field and laboratory, significant population differences were observed in the latency to return to a foraging mode following retreat into the protection of the web-funnel. The population exposed to predation pressure by birds exhibited the longer latency to return. Within this population, moreover, latency to return to a foraging mode covaried at an individual level with latency to respond to prey encountering the web-sheet.
Cellular resistance to the antimelanoma immunotoxin ZME-gelonin and strategies to target resistant cells.

The development of cellular resistance to immunotoxins has been demonstrated in a variety of models and can involve a number of mechanisms. For the present study, an immunotoxin was utilized composed of an antimelanoma antibody ZME-018 recognizing a 240-kDa surface glycoprotein (gp 240) and the plant toxin gelonin. Human melanoma cells (A375-M) were grown in the presence of increasing amounts of ZME-gelonin and a clonal variant (A-375-ZR) was developed that was 100-fold resistant to ZME-gelonin compared to parental cells. Scatchard analysis showed that the A375-M parental cells had 260×103 ZME-gelonin-binding sites/cell with relatively low affinity (5 nM). In contrast, resistant A375-ZR cells demonstrated a reduced number of low-affinity sites (160×103/cell), but showed a small number (47×103) of higher-affinity sites (0.8 nM). Internalization rates and degradation rates of 125I-labeled ZME-gelonin were identical in both the parental and resistant cells. A375-ZR cells were found to be more resistant to vincristine and doxorubicin than were parental cells. Both cell lines were almost equally sensitive to native gelonin, 5-fluorouracil (5-FU), cisplatin, melphalan, carmustine, interferon γ (IFNγ) and IFNα. In addition, both cell lines were equally sensitive to another gelonin-antibody conjugate that binds to cell-surface, GD2 (antibody 14G2A). However, resistant cells were twice as sensitive to the cytotoxic effects of etoposide than were parental cells. Finally, a variety of agents were tested in combination with ZME-gelonin against A375-ZR cells in an attempt to identify agents to augment immunotoxin cytotoxic effects against resistant cells. The agents 5-FU, cisplatin, IFNγ, IFNα, and etoposide were the most effective in augmenting the cytotoxicity of ZME-gelonin against resistant cells. These studies suggest that development of resistance to one immunotoxin does not cause development of cross-resistance to other gelonin immunotoxins. Further, specific biological response modifiers and chemotherapeutic agents may be effective in augmenting the effectiveness of immunotoxins and specifically targeting or reducing the emergence of immunotoxin-resistant cells.
Synthesis and characterisation of a new hexahydrobenzodipyrrole fibre

Abstract The characterisation of a new fibre-forming hexahydrobenzodipyrrole polyamide is described from initial synthesis to tensile testing of filaments prepared under different conditions. Physical, solubility and fibre-spinning properties of the polymer are studied. Thermal properties are compared to those of a model compound and a commercial product. A satisfactory dope was prepared from which fibres were extruded by dry and wet spinning techniques.
Fetal anemia following maternal exposure to 5-fluorouracil in the rat.

Previous studies from our laboratory have shown that maternal 5-fluorouracil (5-FU) exposure on day 14 of gestation (GD14) in the rat results in dose-dependent retardation of both cell cycle progression and growth of embryonic liver. At this developmental stage, hepatic erythropoiesis is the primary source of new circulating fetal erythrocytes. This study examined dose-dependent hematological changes in the fetus after maternal 5-FU exposure (0, 20, 30, 40 mg/kg on GD14) to assess 1) hematopoiesis as a potential target for 5-FU developmental toxicity and 2) the role of the observed 5-FU-induced fetal anemia in adverse developmental outcome. Standard clinical hematological parameters, including hematocrit, hemoglobin content, and erythrocyte counts, were measured in fetal blood drawn by cardiac puncture. Dose-related deficits were observed in all of these parameters within 48 hr of 5-FU administration. Calculation of various red cell indices revealed a concomitant increase in mean cell volume and mean cell hemoglobin. These changes were preceded by depletion of hepatic precursor populations which was evident by 24 hr after maternal exposure to 30 or 40 mg/kg. At doses of 20 and 30 mg/kg there was full and moderate recovery, respectively, in these endpoints by 72 hr after dosing, but persistent deficits were observed at 40 mg/kg. Fluorescence microscopy of Hoechst-stained fetal blood smears revealed that at both 48 and 72 hr after dosing, the proportion of nucleated yolk sac-derived erythrocytes was increased relative to control.(ABSTRACT TRUNCATED AT 250 WORDS)
Force-Directed Placement of VLSI Circuits

The placement significantly influences the quality of a circuit. In the past decades a lot of placement algorithms were presented. The most popular ones are summarized here. Force-directed placers are able to place VLSI circuits with low wirelength within a suitable time. Examples for force-directed placers are Kraftwerk and Kraftwerk2, which start with an initial placement and use forces to evenly distribute the modules inside the placement area.
Metabolism in vitro of digitoxigenin by rat liver homogenates.

Abstract Digitoxigenin is metabolized in vitro by rat liver homogenates and subcellular fractions. No metabolism by cardiac tissue homogenates was observed, with only limited conversion by kidney tissue homogenates. The primary product is 3-epidigitoxigenin, with smaller amounts of 3-dehydrodigitoxigenin and more polar metabolites being detected. The microsomal hydroxylation system can be induced by treatment of the animals with phenobarbital.
Increased oxidative stress with aging reduces chondrocyte survival: Correlation with intracellular glutathione levels

Objective To examine the role of oxidative stress in mediating cell death in chondrocytes isolated from the articular cartilage of young and old adult human tissue donors. Methods Cell death induced by the oxidant SIN-1 was evaluated in the alginate bead culture system using fluorescent probes to assess membrane integrity. Generation of peroxynitrite by the decomposition of SIN-1 was confirmed by positive immunostaining of treated cells for 3-nitrotyrosine. Determinations of oxidized glutathione (GSSG) and reduced glutathione (GSH) were performed in monolayer cultures using an enzyme- recycling assay. Cells were depleted of intracellular glutathione either by the addition of DL-buthionine-(S,R)-sulfoximine or by removal of L-cystine from the culture media. The activity of cellular antioxidant enzymes was determined spectrophotometrically by the decay of substrate from the reaction mixture. Results More chondrocytes (>2-fold) from old donors (≥50 years) died after exposure to 1 mM SIN-1 relative to those derived from young donors (18–49 years). Although autocrine production of insulin-like growth factor 1 (IGF-1) promotes chondrocyte survival, pretreatment with IGF-1 could not prevent the cell death induced by SIN-1 exposure. Cells isolated from old donors had a higher ratio of GSSG to GSH. Glutathione reductase is the principal enzyme involved in the regeneration of GSH from GSSG. Treatment of chondrocytes with SIN-1 to induce oxidative stress in vitro resulted in the decreased activity of glutathione reductase and thioredoxin reductase, but not catalase. Cells depleted of intracellular glutathione were more susceptible to cell death induced by SIN-1. Conclusion These results provide evidence that increased oxidative stress with aging makes chondrocytes more susceptible to oxidant-mediated cell death through the dysregulation of the glutathione antioxidant system. This may represent an important contributing factor to the development of osteoarthritis in older adults.
Nano‐, Bio‐, Multi‐, Inter‐, … : Polymer Research in an Era of Prefixes

The polymer field has experienced enormous growth in the last decade. One of the most exciting aspects of this growth is that it is not simply an extrapolation of pre‐existing lines of research, bu...
Floodplain management into the 21st century: a blueprint for change ― sharing the challenge

ABSTRACT The article is a summary of the Interagency Floodplain Management Review Committee's Report to the Clinton Administration's Floodplain Management Task Force. The author was a member of the Committee, which proposes a better way to manage the nation's floodplains. The report not only describes the nature and extent of 1993 flooding and government efforts to cope with the event, but also presents a blueprint for change. This blueprint is directed at both the upper Mississippi River Basin and the nation as a whole. Its foundation is a sharing of responsibilities and accountability among all levels of government, business, and private citizens. It provides for a balance among the many competing river and floodplain uses; it recognizes, however, that all existing floodplain activity simply cannot be discarded as inappropriate. The Committee believes that, if implemented, the recommended approach will bring about changes necessary to reduce flood vulnerability to both the infrequent major flood events ...
The predictive value of radiographs in the evaluation of unilateral and bilateral anterior cruciate ligament injuries

A review of 250 cases of surgical reconstruction of the anterior cruciate ligament identified 24 patients with bilateral complete tears of the anterior cruciate ligament. Twenty of these patients had previous reconstruction of one anterior cruciate ligament before rupture of the opposite ligament. Twelve injuries occurred during the same activity that was responsible for the initial opposite injury. The average time between surgical reconstruction and rupture of the opposite ligament was 29.3 months (range, 3 to 103). No significant demographic differences existed between patients with unilateral or bilateral ruptures of the anterior cruciate ligament. Standardized measurements of intercondylar notch height and width and medial and lateral femoral condyle height and width were performed on routine notchview height and width were performed on routine notchview radiographs of 31 knees of patients with bilateral injuries, 30 with unilateral injury, and 30 with no anterior cruciate ligament injury. Statistical analysis revealed no significant differences between the three groups when comparing absolute measures or any of eight mathematical ratios calculated from these measurements. We concluded that measurements of the intercondylar notch made from radiographs may not be reliable predictors of injury to the anterior cruciate ligament. We found no significant clinical or demographic differences between patients with unilateral or bilateral complete ruptures of the anterior cruciate ligament.
Phase transitions and criticality: Finite-size effects, conformal covariance and other current problems

Abstract This article outlines a tutorial review of some recent progress in the theory of phase transitions and criticality. Topics mentioned are: |φ| 6 field theories in ( d =3)-dimensional space which correspond to the limits of tricriticality in spherical models; the desirability of finding real systems displaying critical endpoints, etc., in a magnetic field; scaling theories for first-order magnetic transitions in block and cylinder geometries, including spin-wave contributions, ϵ=4 - d expansions for finite-size effects at and near criticality; the universal correlation length amplitude for critical-point correlations in a finite cylinder and its evaluation in d = 2 dimensions on the basis of conformal covariance ; the predictions of conformal covariance for other finite-size and surface critical-point properties; the implications, stemming from field theory, of conformal covariance and unitarity for general criticality in two dimensions, including infinitely many sets of exact critical exponents for Ising-like, three-state Potts-like, … systems; the discovery of new, exactly soluble two-dimensional, “restricted solid-on-solid” models which display all the predicted conformally covariant multicritical points and a second infinite set as well!
Successful treatment, despite a non-surgical approach, of severe infective endocarditis

A 60-year-old man with a history of Child-Pugh class B cirrhosis was admitted to the hospital with 4–5 days of nausea, vomiting and altered mental status. Following the development of fever in the intensive care unit and methicillin-sensitive Staphylococcus aureus bacteraemia, a large (15 mm) vegetation was discovered on the anterolateral papillary muscle of the mitral valve. Following a thorough multidisciplinary evaluation, the patient was considered to be a poor surgical candidate due to the significant perioperative complications associated with Child-Pugh class B cirrhosis. The patient was treated with 6 weeks intravenous nafcillin as an outpatient. Echocardiography following the treatment course revealed that the vegetation had completely resolved without any valvular dysfunction. This case report emphasises that medical management remains an effective alternative to surgery in complicated cases of infective endocarditis.
Editorial: Submitting Manuscripts for Publication Through Manuscript Central

The electronic age and the 21st century have caught up with the Journal of Digital Imaging (JDI), and we are converting from using manual methods to using online manuscript submission and management. This issue and the next will contain tutorials on using Manuscript Central ™ to submit and review manuscripts for publication in JDI. Our goal is to simplify the process, manage myriad tasks, and reduce turnaround time for manuscripts. Once a manuscript is ready to be published, Springer-Verlag New York, displays the completed article on the “Online First” Web site. From the SCAR (Society for Computer Application in Radiology) home page (http://www.scarnet.org ), links from Publications—JDI lead to the Journal of Digital Imaging Online. Members of SCAR may view and download articles from the Springer-Verlag Web site at any time. The SCAR office can remind you of your password if you have forgotten it.
Discrimination of auditory from nonauditory toxicity by reflex modulation audiometry: Effects of triethyltin☆

The evaluation of toxicity in sensory systems presents particular problems because of the need to distinguish specific sensory loss from other toxic effects. It has recently been shown that modulation of reflex behavior by low-intensity test stimuli can be used to provide a rapid assessment of sensory acuity and of ototoxic hearing loss. In this report the ability of the method to distinguish the known neuromuscular consequences of triethyltin (TET) from hearing loss is demonstrated. Rats treated with TET bromide (30 mg/liter) in their drinking water for 3 weeks showed a profound decrease in acoustic startle reflex amplitudes which was apparent prior to overt neuromuscular weakness and subsequent hindlimb paralysis. Following cessation of treatment, startle levels recovered to preexposure values. Despite these large changes in startle reflex amplitudes, TET treatment did not alter the ability of pure tone stimuli to modulate reflex behavior. These results indicate that TET as administered in these studies disrupted neuromuscular function but did not affect hearing.
The Vector Magnetic Field, Evershed Flow, and Intensity in a Sunspot

We present results of simultaneous observations of the vector magnetic field, Evershed flow, and intensity pattern in a nearly axisymmetric sunspot, made with the Advanced Stokes Polarimeter at the Vacuum Tower Telescope at NSO (Sacramento Peak). The vector magnetic field is determined from the Stokes profiles of the magnetically sensitive lines Fe I 630.15 and 630.25 nm, and Doppler velocities and intensities are measured in several lines including the weak C I 538.03 nm line, formed in the deepest layers of the atmosphere. The strength of the magnetic field decreases with increasing zenith angle (angle of inclination to the local vertical), and this decrease is nearly linear over most of the range of values in the sunspot. Magnetic field strength and continuum intensity are inversely related in the sunspot in a manner similar to the characteristic nonlinear relationship found by Kopp & Rabin in the infrared line Fe I 1564.9 nm. A different relationship is found between magnetic field strength and core intensity (in Fe I 630.25 nm), however, with the curve doubling back to give two distinct values of field strength at the same core intensity in the penumbra—the higher and lower field strengths corresponding to the inner and outer penumbra, respectively. In the penumbra the magnetic field pattern consists of spokelike extensions of stronger, more vertical magnetic field separated by regions of weaker, nearly horizontal magnetic field, as found by Degenhardt & Wiehr and Lites et al. The penumbral magnetic field extends outward beyond the outer continuum boundary of the sunspot, forming a canopy at the height of formation of Fe I 630.25 nm. Our results for the Evershed flow confirm the discovery by Rimmele that this flow is generally confined to narrow, elevated channels in the penumbra. In the Fe I 630.25 nm line and other strong photospheric lines we see isolated, radially elongated channels of Evershed flow crossing the outer penumbra. These flow channels lie in regions of the penumbra where the magnetic field is very nearly horizontal. In the weak C I 538.03 nm line (formed at a height h = 40 km) the flow pattern shows small, isolated patches of upflow, lying at the inner end of the Fe I flow channels where the magnetic field is more inclined to the horizontal. These patches presumably correspond to the upstream footpoints of the arched magnetic flux tubes carrying the Evershed flow. For some of the flow channels we find isolated patches of strong downflow in the C I line just outside the penumbra that might correspond to the downstream footpoints of these flux tubes. There is a weak association between the Evershed flow channels and the dark filaments seen in continuum intensity in the penumbra, but a much stronger association between the flow and the dark filaments seen in core intensity measured in the same spectral line.
Immunologic factors in human milk during the first year of lactation

The effects of the duration of lactation upon lactoferrin, lysozyme, total IgA, SIgA, SIgA antibodies to Escherichia coli somatic antigens and leukocytes in human milk were investigated. Longitidinal and cross-sectional studies were performed with milk collected from women 20 to 35 years of age during the first year of lactation. Collection and storage conditions and immunologic analyses were controlled to minimize confounding variables. The concentrations of lactoferrin, total IgA, and leukocytes and the uptake of 3 H-thymidine by phytohemagglutinin-stimulated lymphocytes fell during the first several weeks of lactation; afterward, the levels of lactoferrin and IgA stabilized. Approximately 90% of total IgA in human milk during the year was SIgA. Secretory IgA antibody titers to E. coli increased in some individuals studied longitudinally suggesting that the enteromammary gland pathway of SIgA antibody production was active after several weeks of lactation. Moreover, the concentrations of lysozyme, after falling to a nadir of 20 to 30 μg/ml at 2 to 4 weeks, rose to 200 to 300μg/ml by six months and remained elevated. The immunologic system in human milk undergoes remarkable changes which may represent adaptations for the recipient infant.
Improved astrometry of (99942) Apophis

Abstract We have remeasured over 430 astrometric observations of (99942) Apophis using the 2MASS reference catalog to reduce the level of astrometric bias in the data caused by our previous use of the USNO-B1.0 reference catalog. The new measurements show an RMS residual of just 0.12 ″ , which is comparable to the size of the bias that was present in the positions referred to the USNO-B1.0 catalog. We also present our method for computing astrometric uncertainties for each individual observation. These new measurements and uncertainties should allow considerably more reliable impact predictions.
A comparison of three information gathering strategies in DAI systems under noisy conditions

Abstract This paper investigates a problem of task allocation in Distributed Artificial Intelligence (DAI) systems, where a coordinator allocates tasks among multiple agents in an optimal manner. In making the task allocation, the coordinator needs to understand the preference orders of the agents for the different task bundles. The coordinator does this by adopting an information acquisition strategy that leads to an optimal system welfare. Three different information acquisition strategies are investigated here. The strategies are compared in a noisy environment for the quality of information they provide in terms of the deviation from optimal system welfare. Copyright 1996 Elsevier Science Ltd
Bone marrow as a cell source for tissue engineering heart valves

Abstract Background This study was designed to assess the feasibility of using ovine bone marrow-derived mesenchymal stem cells to develop a trileaflet heart valve using a tissue engineering approach. Methods Bone marrow was aspirated from the sternum of adult sheep. Cells were isolated using a Ficoll gradient, cultured, and characterized based on immunofluorescent staining and the ability to differentiate down a specific cell lineage. Two million cells per centimeter squared were delivered onto a polyglycolic acid (PGA), poly-4-hydroxybutyrate (P4HB) composite scaffold and cultured for 1 week before being transferred to a pulse duplicator for an additional 2 weeks. The tissue-engineered valves were assessed by histology, scanning electron microscopy, and biomechanical flexure testing. Results Cells expressed SH2, a marker for mesenchymal stem cells, as well as specific markers of smooth muscle cell lineage including α-smooth muscle actin, desmin, and calponin. These cells could be induced to differentiate down an adipocyte lineage confirming they had not fully committed to a specific cell lineage. Preliminary histologic examination showed patchy surface confluency confirmed by scanning electron microscopy, and deep cellular material. Biomechanical flexure testing of the leaflets showed an effective stiffness comparable to normal valve leaflets. Conclusions Mesenchymal stem cells can be isolated noninvasively from the sternum of sheep and can adhere to and populate a PGA/P4HB composite scaffold to form "tissue" that has biomechanical properties similar to native heart valve leaflets. Thus, bone marrow may be a potential source of cells for tissue engineering trileaflet heart valves, particularly in children with congenital heart disease.
Providing activation-induced cytidine deaminase (AID) to nuclear export inhibitors. Response to: "Complex downstream effects of nuclear export inhibition in B-cell lymphomas: a possible role for activation-induced cytidine deaminase".

We read an enlightening piece of work from Shivarov and colleagues on the downstream secondary effects of CRM1 inhibition that involves activation-induced (cytidine) deaminase (AID).[1][1] These Authors have previously shown evidence that nuclear retention of AID plays a strong role in promoting
Vardeman, S. B. and Morris, M. D. (2013), “Majority Voting by Independent Classifiers can Increase Error Rates,” The American Statistician, 67, 94-96: Comment by Baker, Xu, Hu, and Huang and Reply

Vardeman and Morris (VM) found a counterexample to the assertion that a majority voting classifier always performs better than its independent component classifiers. VM's counterexample applies to independent classifiers, but biostatisticians are often more interested in conditionally independent classifiers. In biomedical studies, where class is disease status, classifiers are inherently dependent simply because positivity of any reasonable classifier depends on the presence or absence of disease. Conditional independence of classifiers, given disease status, could arise if the classifiers are detecting different biological phenomenon, such as tissue abnormalities versus protein markers. To explore how majority voting affects classification performance with conditionally independent classifiers, we investigated many examples (Figure 1). Much as we expected, we found that it generally works quite well. However, we also found that conditional independence is not a sufficient condition to ensure that majority voting always leads to better classification performance than the individual classifiers. Figure 1 Comparison of ROC curves for majority voting classifier and conditionally independent component classifiers. The 45-degree line is included for reference. As with VM, we considered two classes and component classifiers with identical classification performances. To measure classification performance we used receiver operating characteristic (ROC) curves. ROC curves play a central role in the evaluation of diagnostic and screening tests (Baker 2003; Pepe 2003). In accordance with a decision theory view of ROC curves (Baker, Van Calster, and Steyerberg 2012), we restricted our investigation to ROC curves that are concave, namely with monotonically decreasing slopes from left to right. For a given cutpoint x of a score, let fpr(x) and tpr(x) denote the false positive and true positive rates of the component classifier. The ROC curve for the component classifier plots tpr(x) versus fpr(x). At a given cutpoint, the true positive rate for the majority voting classifier is the probability of three or exactly two true positives among the component classifiers, namely tprM(x) = tpr(x)3 + 3 tpr(x)2 {1−tpr(x)}. Similarly the false positive rate for the majority voting classifier is fprM(x) = fpr(x)3 + 3 fpr(x)2 {1−fpr(x)}. The ROC curve for the majority voting classifier plots tprM(x) versus fprM(x). We considered the following six cases.
Iterative hard thresholding for compressed sensing with partially known support

Recent works in modified compressed sensing (CS) show that reconstruction of sparse or compressible signals with partially known support yields better results than traditional CS. In this paper, we extend the ideas of these works to modify the iterative hard thresholding (IHT) algorithm to incorporate known support in the recovery process. We present a theoretical analysis that shows that including prior support information relaxes the conditions for stable reconstruction. Numerical results show that the IHT modification improves performance, thereby needing fewer samples to yield an approximate reconstruction.
Binary kinetics in the Y-Ba-Cu system: 2. Nanosized particles

The kinetics of binaty mixtures of Y2O3 – BaCO3–CuO (Ba–Cu) and Y2O3 –CuO(Y–Cu) prepared by citrate sot-gel techniques were studied in both air and helium. Particle sizes resulting from the sol – gel preparation were between 5 and 100 nm, and the prevailing kinetics differed significantly from those observed in the companion study of micron-sized particles. That is, nucleation-growth kinetics of the Avrami-Erofe'eu type adequately model the kinetics over the entire conversion range as opposed to the diffusion mechanisms that describe the kinetics in larger sized particles. An alternate nucleation-growth model, which neglects overlapping volumes during reaction (Austin – Rickett model), was also adequate in the Ba–Cu system where particle size/spacing was larger, but was only applicable in other reaction systems at lower conversions. Activation energies obtained from the Avrami- Erofe'ev were consistently lower than those from the Austin - Rickett model, because the former model contains two parameters that are temperature-sensitive.
Caseworker assessments of risk for recurrent maltreatment: association with case-specific risk factors and re-reports.

Abstract Objective This article focuses on caseworkers’ assessments of risk of maltreatment recurrence among families in contact with social services. Specifically, the article has two primary goals: (1) to examine the association between caseworkers’ risk assessments and demographic, child, parent and family-level risk factors; and (2) to examine agreement between caseworkers’ risk assessments and any subsequent report, or reports, of maltreatment. Method Data are from the baseline, 12-month, and 18-month assessments of the National Survey for Child and Adolescent Well-Being (NSCAW), a nationally representative sample of youth and families who were the subjects of allegations of maltreatment investigated by child welfare agencies. The sample consisted of a subset of NSCAW participants: cases with a report of child physical abuse or neglect who were not placed in out-of-home care (N = 2,139). Results Analyses indicated that parent-level risk factors and a prior report of maltreatment were most strongly associated with caseworkers’ assessments of risk for both physical abuse and neglect cases. A smaller set of factors, which varied by the type of maltreatment, were associated with a subsequent report of maltreatment. Despite some overlap in correlates of risk assessment and subsequent reports, analyses indicated that agreement between caseworkers’ assessments of risk and re-reports was low. Conclusions Findings suggest that although caseworkers’ assessments were associated with a limited set of risk factors from the literature, few of these factors also were associated with a recurrent report of maltreatment. Correspondence between caseworkers’ assessments of risk and a subsequent report of maltreatment was low, suggesting that considerable work may be needed to improve accuracy and identification of cases most at risk. Practice implications This study provides information to assist caseworkers, administrators, and policymakers in thinking critically about risk assessment policies and procedures. Although caseworkers’ assessments of risk were associated with some of the empirical predictors of recurrent maltreatment, their assessments were only slightly better than guessing. Agreement between caseworkers’ risk assessments and actual subsequent reports was better for low-risk cases, but primarily because the majority of cases did not have a subsequent report during the study period. Clearly, considerable improvement in risk assessment is needed so that at-risk families can be better identified and the limited services available can be directed toward those most in need.
Repair of clustered uracil DNA damages in Escherichia coli.

Multiply damaged sites (MDS) are defined as greater than/equal to two lesions within 10–15 bp and are generated in DNA by ionizing radiation. In vitro repair of closely opposed base damages ≥2 bp apart results in a double strand break (DSB). This work extends the in vitro studies by utilizing clusters of uracil DNA damage as model lesions to determine whether MDS are converted to DSBs in bacteria. Lesions were positioned within the firefly luciferase coding region, transformed into bacteria (wild-type, uracil DNA glycosylase-deficient, ung–, or exonuclease III and endonuclease IV-deficient, xth–nfo–) and luciferase activity measured following repair. DSB formation was expected to decrease activity. Two closely opposed uracils separated by ≤7 bp decreased luciferase activity in wild-type and xth–nfo–, but not ung– bacteria. Growth of bacteria to obtain plasmid-containing colonies demonstrated that the plasmid was destroyed following the mis-repair of two uracils positioned 7 bp apart. This study indicates a DSB is formed when uracil DNA glycosylase initiates repair of two closely opposed uracils ≤7 bp apart, even in the absence of the major apurinic endonucleases. This work supports the in vitro studies and demonstrates that DNA repair is not always advantageous to cells.
Repeated administration of synthetic oligodeoxynucleotides expressing CpG motifs provides long-term protection against bacterial infection

Synthetic oligodeoxynucleotides (ODN) expressing unmethylated CpG motifs stimulate an innate immune response characterized by the production of polyreactive immunoglobulin M antibodies and immunomodulatory cytokines. This immune response has been shown to protect mice from challenge by Listeria monocytogenes and Francisella tularensis for up to 2 weeks. By repeatedly administering CpG ODN two to four times/month, we found that this protection could be maintained indefinitely. Protection was associated with a significant increase in the number of spleen cells that could be triggered by subsequent pathogen exposure to secrete gamma interferon and interleukin-6 in vivo (P < 0.01). ODN-treated animals remained healthy and developed neither macroscopic nor microscopic evidence of tissue damage or inflammation. Thus, repeated administration of CpG ODN may provide a safe means of conferring long-term protection against infectious pathogens.
Controlling FD and MVD inferences in multilevel relational database systems

The authors investigate the inference problems due to functional dependencies (FD) and multivalued dependencies (MVD) in a multilevel relational database (MDB) with attribute and record classification schemes, respectively. The set of functional dependencies to be taken into account in order to prevent FD-compromises is determined. It is proven that incurring minimum information loss to prevent compromises is an NP-complete problem. An exact algorithm to adjust the attribute levels so that no compromise due to functional dependencies occurs is given. Some necessary and sufficient conditions for MVD-compromises are presented. The set of MVDs to be taken into account for controlling inferences is determined. An algorithm to prevent MVD-compromises in a relation with conflict-free MVDs is given. >
Hemodialysis-associated endovascular device infection

Bacteremia is a major concern in hemodialysis patients being evaluated for fever, and identifying a source of ongoing infection is often challenging. In the absence of an obvious catheter-related nidus, clinicians typically consider a wide range of entities including endocarditis, osteomyelitis, joint infections and epidural abscesses. Despite advanced CT, magnetic or radionuclide imaging techniques, however, the site of continuing or relapsing infection can remain occult. We believe that endovascular stents are an under-appreciated potential location for such infections. The use of these devices has become increasingly common and is of particular concern when deployed for access-associated venous stenoses in dialysis patients. With the widespread use of endovascular devices, and especially in circumstances when care is rendered at multiple facilities, the patients and their medical providers may be unaware that those devices are present. There is much human and animal model literature describing the use of arterial and venous stents made from bare metal or combined with polymeric materials [1]. Although they are subject to infection upon implantation, it appears that the risk decreases with the endothelialization that historically was thought to occur over approximately 4 weeks. The speed and ultimate coverage area of cell growth is, however, controversial [2]. There is evidence that stents can become infected more than a month post-insertion, perhaps when associated with incomplete endothelial growth, thrombi or local trauma (e.g. needle cannulation) [3]. We present here a patient with persistent bacteremia due to an infected vena cava stent, complicated by the presence of a vegetation. This case highlights the importance of detecting these devices when evaluating febrile hemodialysis patients and the challenges in determining the optimal surgical or medical plan of care.
Assessing Curriculum Effectiveness: A Survey of Uniformed Services University Medical School Graduates

ABSTRACT Purpose: This study assessed alumni perceptions of their preparedness for clinical practice using the Accreditation Council for Graduate Medical Education (ACGME) competencies. We hypothesized that our alumni's perception of preparedness would be highest for military-unique practice and professionalism and lowest for system-based practice and practice-based learning and improvement. Method: 1,189 alumni who graduated from the Uniformed Services University (USU) between 1980 and 2001 completed a survey modeled to assess the ACGME competencies on a 5-point, Likert-type scale. Specifically, self-reports of competencies related to patient care, communication and interpersonal skills, medical knowledge, professionalism, systems-based practice, practice-based learning and improvement, and military-unique practice were evaluated. Results: Consistent with our expectations as the nation's military medical school, our graduates were most confident in their preparedness for military-unique practice, which i...