cssi/SciSciGPT-SciSciNet huggingface dataset:
The risk of recurrent preterm birth is significantly higher in patients with a previous history of very early premature delivery

540 541 THE RISK OF RECURRENT PRETERM BIRTH IS SIGNIFICANTLY HIGHER IN PATIENTS WITH A PREVIOUS HISTORY OF VERY EARLY PREMATURE DELIVERY ERIN CLARK, MICHAEL S. ESPLIN, ALISON FRASER, ELIZABETH O’BRIEN, GERI MINEAU, MICHAEL W. VARNER, University of Utah, Obstetrics and Gynecology, Salt Lake City, UT; University of Utah-Huntsman Cancer Institute, Population Sciences, Salt Lake City, UT University of Utah-Huntsman Cancer Institute, Population Sciences, Salt Lake City, UT University of Utah-Huntsman Cancer Institute, Oncological Sciences, Salt Lake City, UT OBJECTIVE: We hypothesized that the risk of recurrent PTB would be significantly higher in women with a history of very premature PTB. Our objective was to quantify the risk of recurrent PTB in patients with a previous history of very early PTB. STUDY DESIGN: The Utah Population Database was used to identify all women who had two or more deliveries in the state of Utah with the first birth occurring between 1989 and 2001. The final database included 99,499 patients who had 224,849 consecutive births. The relative risks for preterm birth were calculated based on the gestational age of the previous delivery. RESULTS: The Table depicts the rate of recurrent PTB for the 2nd birth based on the GA of the 1st delivery. Although the rate of recurrent PTB < 32 weeks was 15.9% in the next birth, the rate of recurrence fell to 7.1% in the third birth and 2.8% in the fourth birth. The relative risk of PTB < 32 weeks’ gestation in the second pregnancy was significantly higher among women with a history of PTB at < 32 weeks (RR = 27.2) as compared with women with a previous PTB at 32-33 weeks (RR = 5.95). CONCLUSION: Patients have recurrent PTB at approximately the sameGA as their previous PTB, suggesting that the etiologies for PTB differ at early vs later gestations. Although patients with prior PTB have a substantial recurrence risk, they can be reassured by the fact that a majority subsequently deliver at or near term. Individuals with subsequent term deliveries have an even better prognosis.
Endobronchial Brachytherapy for Lung Cancer: What Can the Patient and Family Expect?

A s early as 1922, the implantation of radon seeds in pulmonary lesions via rigid bronchoscope has been described (Muto, Ravo, Panelli, Ligouri, & Gaetano, 2000). The term brachytherapy is derived from the Greek words brachys, meaning short, and theraepia, meaning treatment, and refers to short-distance radiation. With the advent of remote afterloading equipment, both lowand highdose brachytherapy can be performed. Treatment involves the placement of encapsulated radioactive sources within or in close proximity to a tumor. It is a modality available for palliative treatment of airway obstruction caused by tumor, usually bronchogenic carcinoma (Villanueva, Lo, & Beamis, 1995). High dose rate (HDR) endobronchial brachytherapy has been found to effectively relieve airway obstruction (Delclos, Davis, Komaki, Garden, & Morice, 1996). Studies have compared the efficacy of this treatment related to symptom management and have demon-
Evolutionary Convergence of Higher Brain Centers Spanning the Protostome-Deuterostome Boundary

Currently available evidence supports a single origin for the centralized nervous system of bilaterally symmetrical animals. Beneath the staggering diversity of protostome and deuterostome nervous sys
Modification of Herbicide Binding to Photosystem II in Two Biotypes of Senecio vulgaris L

The present study compares the binding and inhibitory activity of two photosystem II inhibitors: 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron [DCMU]) and 2-chloro-4-(ethylamine)-6-(isopropyl amine)- S -triazene (atrazine). Chloroplasts isolated from naturally occurring triazine-susceptible and triazine-resistant biotypes of common groundsel ( Senecio vulgaris L.) showed the following characteristics. ( a ) Diuron strongly inhibited photosynthetic electron transport from H 2 O to 2,6-dichlorophenolindophenol in both biotypes. Strong inhibition by atrazine was observed only with the susceptible chloroplasts. ( b ) Hill plots of electron transport inhibition data indicate a noncooperative binding of one inhibitor molecule at the site of action for both diuron and atrazine. ( c ) Susceptible chloroplasts show a strong diuron and atrazine binding ( 14 C-radiolabel assays) with binding constants (K) of 1.4 × 10 −8 molar and 4 × 10 −8 molar, respectively. In the resistant chloroplasts the diuron binding was slightly decreased (K = 5 × 10 −8 molar), whereas no specific atrazine binding was detected. ( d ) In susceptible chloroplasts, competitive binding between radioactively labeled diuron and non-labeled atrazine was observed. This competition was absent in the resistant chloroplasts. We conclude that triazine resistance of both intact plants and isolated chloroplasts of Senecio vulgaris L. is based upon a minor modification of the protein in the photosystem II complex which is responsible for herbicide binding. This change results in a specific loss of atrazine (triazine)-binding capacity.
Mechanistic Relationship Between Membrane Type-1 Matrix Metalloproteinase and the Myocardial Response to Pressure Overload

Background—Although matrix metalloproteinases (MMPs) were initially thought to result primarily in extracellular matrix degradation, certain MMP types, such as membrane type-1 (MT1) MMP, may also be involved in profibrotic cascades through hydrolysis of latency-associated transforming growth factor–binding protein (LTBP-1) and activation of transforming growth factor–dependent profibrotic signaling. The present study tested the hypothesis that MT1-MMP plays a direct role in the matrix remodeling response to a left ventricular (LV) pressure overload (PO) stimulus. Methods and Results—Wild-type (WT) and transgenic mice with cardiac-restricted MT1-MMP overexpression or MT1-MMP reduced expression underwent PO for 4 weeks. PO resulted in a 57% increase in LV mass (no change in LV end diastolic volume, resulting in an increase in the LV mass/volume ratio consistent with concentric remodeling), a 60% increase in MT1-MMP–mediated LTBP-1 hydrolysis and a 190% increase in collagen content in WT mice. Although LV ma...
Capacity of the Adult Chicken for Exercise on the Treadmill

Abstract ALTHOUGH various exercise tolerance tests are widely used in clinical practice and medical research to estimate physical and physiological functions (see, for example, Bard, Chapter 47, 1956; and Astrand, 1956), they seem to have found limited application in the animal sciences. In poultry, forced physical activity has been used in connection with such studies as: stress and adrenal hormone interaction (Garren and Shaffner, 1954; Connor and Shaffner, 1954); lipid metabolism and atherogenesis (Warnock et al., 1957; Wong et al., 1959); hematological changes (Anderson et al., 1959); blood uric-acid levels (Hudson and Taylor, 1960); feather removal (Knapp and Newell, 1961); and the mortality differences between genetically selected hyper- and hypotensive strains (Sturkie and Textor, 1961). However, apart from the data supplied by Garren and Shaffner (1954) for the growing chick exercised in a revolving drum, little appears to be known of the characteristics involved in the bird’s resistance to muscular fatigue….
A Centrosomal Localization Signal in Cyclin E Required for Cdk2-Independent S Phase Entry

Excess cyclin E-Cdk2 accelerates entry into S phase of the cell cycle and promotes polyploidy, which may contribute to genomic instability in cancer cells. We identified 20 amino acids in cyclin E as a centrosomal localization signal (CLS) essential for both centrosomal targeting and promoting DNA synthesis. Expressed wild-type, but not mutant, CLS peptides localized on the centrosome, prevented endogenous cyclin E and cyclin A from localizing to the centrosome, and inhibited DNA synthesis. Ectopic cyclin E localized to the centrosome and accelerated S phase entry even with mutations that abolish Cdk2 binding, but not with a mutation in the CLS. These results suggest that cyclin E has a modular centrosomal-targeting domain essential for promoting S phase entry in a Cdk2-independent manner.
Improving perception in time-delayed telerobotics

Telerobotics has long struggled to provide realistic force feedback to a user, especially across substantial time delays. Wave variable based controllers provide stable force reflection at frequencies up to a few hertz for typical communication delays; however, the bandwidth of human perception extends to a thousand hertz. In this paper we aim to improve the user's perception by constructing a fundamentally asymmetric controller that better matches the sensory capabilities of the human operator. The improvements stem from two extensions to a normal wave variable controller. First, we revisit wave reflections and utilize wave filtering and shaping to separate distracting oscillations from useful reaction information. This avoids excess damping inherent to impedance matching and enhances the low-frequency feel of the system. Secondly, we incorporate high-frequency feedback from a force sensor located at the slave end-effector. This augmented system leverages the passivation capabilities of wave filters to compensate for energy generation. It renders the complete spectrum of environment interaction forces to the user, allowing the perception of small environment features across substantial delays. These improvements are tested and validated in three simple experiments on a three-degrees-of-freedom testbed.
Why teaching works: The transformative power of pedagogical communication

(1993). Why teaching works: The transformative power of pedagogical communication. Communication Education: Vol. 42, When Teaching “Works”: Stories of Communication in Education, pp. 349-366.
Stability of the Droplet in Magnetic Levitation Mechanism

This paper presents a numerical study of 3-D movement of a conducting spherical droplet in magnetic levitation mechanism. At present, we not only investigate vertical and horizontal movements of the magnetically levitated droplet, but also self-rotation of the droplet. The hybrid 3-D boundary element method (BEM) and finite element method (FEM) with edge elements are used to calculate electromagnetic fields, Lorentz force, and torques with respect to vertical and horizontal axis. By this method, finite elements are used to discretize the spherical droplet region, while boundary elements are applied to free space outside the droplet. The finite element and boundary element regions are then coupled through interface boundary conditions. The coupling of FEM/BEM is solved iteratively. The computed results agree excellently with available analytical and numerical solutions. Furthermore, the complex 3-D movement of the magnetically levitated droplet is solved and analyzed by using the current FE/BE model.Copyright © 2006 by ASME
Adaptive Robust Repetitive Control of Piezoelectric Actuators

Positioning stages using piezoelectric stack actuators (PEA) possess very high theoretical bandwidth and resolution. However, their tracking performance deteriorates as nonlinear dynamics due to inherent hysteresis starts to dominate when the total length of travel increases. When tracking periodic trajectories, which is common in most industrial applications, the uncertain nonlinearity from hysteresis also becomes periodic. Having identified and separated the fast and slow dynamics of the total stage response, we adopt a simple first-order model assuming the inertial dynamics of the stage is negligible in the low tracking frequency range. By approximating the hysteresis mapping function with simple functions, the overall system model is linearly parameterized for subsequent adaptive robust controller design. Exploiting the periodicity of the uncertain hysteresis nonlinearity, it is further parameterized as finite series of harmonic functions, which eliminates the need for an exact inversion model for hysteresis while achieving high tracking accuracy. Experimental results from tracking control of sinusoidal and typical triangular trajectories show tracking error close to the sensor noise level and demonstrate the effectiveness of the approach.
Executive compensation contracts and voluntary disclosure to security analysts

We hypothesize that a CEO’s responsiveness to security analysts’ demands for information about the firm is influenced by the structure of the CEO’s compensation package. Our analysis is based on a sample of 469 CEO presentations to security analyst societies by 149 firms during the period 1984‐1988. Consistent with the argu ments of Nagar (1999; 1998) that CEO shareholdings and golden parachutes reduce the cost to the CEO of disclosing proprietary information, we find that CEO share holdings and the presence of golden parachutes are positively associated with the total amount of information that a CEO discloses at an analyst society presentation. Consistent with the argument that CEOs whose cash compensation is sensitive to firm performance have incentives to release bad news so as to lower expectations about future performance and, hence, bonus targets, CEO cash compensation performance sensitivities are positively associated with the CEO’s willingness to disclose bad news.
Professional Labeling Issues for Post-1982 Drugs

AbstractObservations relating to labeling policy and requirements for post-1962 ANDAs submitted as a result of the Drug Price Competition and Patent Term Restoration Act of 1984 are presented. Topics covered include the issue of listed drug ex clusivity protection, and pharmacokinetic information. Also, a series of topics which the Division of Generic Drugs (DGD) believes require more consideration by applicants is discussed. These topics include: protect from light, unit-dose labeling, inactive ingredient labeling for oral dosage form prescription drugs, theophylline, physician samples, and the NDA rewrite. The presentation en courages applicants to work closely with the DGD labeling staff when planning labeling revision.
Acidity measurements at elevated temperatures. VII. Dissociation of water

The self-dissociation of water has been studied over the temperature range from 0 to 300°C and in KCl media from 0.02m to 2.7m. Also, isothermal pressure coefficients of the dissociation quotients have been obtained in these same media up to 250°C. A potentiometric method employing a hydrogen electrode concentration cell with flowing solutions was employed. The estimated accuracy of logQw values up to 250°C is 0.02 log units and at 300°C is 0.04 log units. Smoothing functions have been found which fit these data along with the precise potentiometric data of Harned and co-workers at low temperatures, the existing calorimetric data up to 55°C and the recent conductimetric measurements of pure water up to 271°C by Bignoldet al., within about 1.5 times the estimated errors. Thermodynamic quantities for the dissociation reaction have been tabulated for rounded values of temperature and ionic strength at the saturation pressure of water. The isothermal pressure coefficients of log Qw varies approximately linearly with the square root of the ionic strength. This and the dependence of logKw on the density of the water is consistent with the assumption that the molal volumes of aqueous ions vary linearly with the compressibility coefficient of water. The heat for the dissociation reaction at infinite dilution is also shown to be strongly dependent on density.
Chinese Opera in Turn-of-the Century Canada: Local History and Transnational Circulation

One of the most curious aspects about Canadian Chinese cultural history is the role of opera theatres. They served as the public face of the community, cultural ambassadors or even artistic curiosities, but at the same time provided Chinese audiences the intimate world of emotive musical drama. Because of their public role, they were often ambitious projects. Since first appearing in Victoria in the 1860s, Chinese theatres played an integral role in its community life. Featuring performance of Cantonese opera, the regional genre known to the majority of Chinese immigrants that came from the Pearl River Delta of southern China, these theatres provided crucial entertainment. Chinese theatres’ success in Victoria, and later in Vancouver, was not an isolated phenomenon, but rather closely connected to other cities along the Pacific coast. The opera business waxed and waned, in large part as a result of the Chinese exclusionist policy in Canada and United States. In the 1910s and 1920s, through joint ventures, Chinese in Canada and the United States succeeded in forming a network of opera performance and revived their fluidity of movement in the Pacific Northwest region. Because this network returned significant mobility to troupes and performers, Chinese theatres flourished again in North America. This article provides a preliminary overview of this body of troupes and performers in Canada, its impact and the national and transnational forces that shaped it. It addresses key issues related to this history: the effect of immigration control, the relevance of Chinese theatres to community life, and the transborder crossings.
Manipulating noise frequencies alters hemispheric contributions to decision making

Participants listened to the Asian disease problem framed in terms of either gains or losses and chose between two plans to combat the disease. All participants heard the problem embedded in other sounds; for some it was the relatively lower-frequency information, and for others it was the relatively higher-frequency information. The classic framing effect appeared only for those participants for whom the problem was the relatively lower-frequency information (p < .05). These results suggest that mixing filtered speech signals and noise may be a way to assess the role of the left and right hemisphere in various aspects of decision making.
Molecular Mechanism of Photosynthetic Oxygen Evolution. A Theoretical Approach

Possible mechanisms for O2 evolution in photosystem I1 (PSII) are studied with a semiempirical one-electron molecular orbital procedure, the extended Hiickel method. The oxygen coupling is examined starting from some known inorganic complexes of manganese. Idealized geometries of four binuclear complexes (two di-p-oxo, one tri-p-oxo and one p-carboxylato-di-1-oxo) are distorted to transform into Oz-bound complexes. The computed Walsh diagrams are analyzed. For these structures the predicted oxidation to dioxygen is energetically unfavorable and would require two two-electron steps forming bound peroxide as an intermediate. An in-plane approach of two oxo ligands has a lower barrier for peroxide bond formation. Four tetranuclear Mn clusters are built combining binuclear complexes, a Mn404 cubane-like core, three (Mn202),(p-02) "dimer of dimers" cores with p4,t2-02 bound either in or out of the Mn4 plane formed by two parallel Mn202 units, and a "planar T" combination of two orthogonal MnzO2 units with a Mn3O2 core and p3,q2-O2 bound to three Mn atoms. The assumed pathway leading to peroxide bond formation in each of these is found to have appreciably lower energy for the (Mn202),(p-02) and the "planar T" models with in-plane 0-0 approach. A slight energetic advantage is calculated in the peroxide to dioxygen step when the oxo ligands are coordinated to at least three Mn ions compared to coordination to only two Mn ions. Qualitative valence bond analysis indicates that release of symmetrically coordinated dioxygen, as in cis- and trans-p-02, requires overcoming an -1-eV electronic barrier for formation of ground-state O2 (triplet). The tetranuclear models are introduced into speculative mechanisms and compared with current knowledge of the photosynthetic water oxidation reaction.
A framework for explaining decision-theoretic advice

Abstract We present strategies for automatically explaining decisions based on Multiattribute Value Theory, the branch of decision theory that addresses tradeoffs among multiple competing objectives. Our explanations are at once empirically motivated and formally sound, retaining the advantages of both artificial-intelligence and decision-theoretic representations for modeling decisions. We demonstrate the explanation strategies with implemented examples in the domains of marketing, process control, and medicine. Although previous approaches to modeling decisions in expert systems often have sacrificed formal specification for transparent operation, our methodology suggests that knowledge engineers can retain the benefits of decision theory without compromising intuitive explanation.
Determination of Generator Stand-by Reserve Requirements

During the past few years there has been a trend toward the use of statistics of forced (unscheduled) generator outages as a basis for calculating the proper amount of stand-by reserve generation for a given power system. This paper presents a method of analysis which was developed to fit the needs of a system having a large number of generators, but which, it is believed, can be used to advantage for small systems also. The method is based partially on previously published results.1,2,3 This method lends itself readily to calculations, involves few approximations, and has sufficient flexibility to take account of several types of machines having different outage factors. Although the discussion is confined to generator outages, the method of analysis here presented may be used for calculation of simultaneous overlap of events of other types for which corresponding assumptions can be made. Examples are random outages of transmission lines and other types of equipment, random use of parallel communication channels, and supply of current to a number of items of equipment, each having a random duty cycle. The method is applicable to any situation which can be represented on a graph similar to Figure 1(A), provided that necessary statistical data are available.
Inhibition of human estrogen synthetase (aromatase) by flavones

Several naturally occurring and synthetic flavones were found to inhibit the aromatization of androstenedione and testosterone to estrogens catalyzed by human placental and ovarian microsomes. These flavones include (in order of decreasing potency) 7,8-benzoflavone, chrysin, apigenin, flavone, flavanone, and quercetin; 5,6-benzoflavone was not inhibitory. 7,8-Benzoflavone and chrysin were potent competitive inhibitors and induced spectral changes in the aromatase cytochrome P-450 indicative of substrate displacement. Flavones may thus compete with steroids in their interaction with certain monooxygenases and thereby alter steroid hormone metabolism.
Unusual Rel-like architecture in the DNA-binding domain of the transcription factor NFATc

TRANSCRIPTION factors of the NFAT family regulate the production of effector proteins that coordinate the immune response1. The immunosuppressive drugs FK506 and cyclosporin A (CsA) act by blocking a Ca2+-mediated signalling pathway leading to NFAT. Although FK506 and CsA have enabled human organs to be transplanted routinely, the toxic side-effects of these drugs limit their usage. This toxicity might be absent in antagonists that target NFAT directly. As a first step in the structure-based search for NFAT antagonists, we now report the identification and solution structure of a 20K domain of NFATc (NFATc-DBD) that is both necessary and sufficient to bind DNA and activate transcription cooperatively. Although the overall fold of the NFATc DNA-binding domain is related to that of NF-κB p50 (refs 2, 3), the two proteins use significantly different strategies for DNA recognition. On the basis of these results, we present a model for the cooperative complex formed between NFAT and the mitogenic transcription factor AP-1 on the interleukin-2 enhancer.
The Current Status of the Philosophy of Biology

The philosophy of biology today is one of the most exciting areas of philosophy. It looks critically across the life sciences, teasing out conceptual issues and difficulties bringing to bear the tools of philosophical analysis to achieve clarification and understanding. This essay surveys work in all of the major directions of research: evolutionary theory and the units/levels of selection; evolutionary developmental biology; reductionism; ecology; the species problem; teleology; evolutionary epistemology; evolutionary ethics; and progress. There is a comprehensive bibliography.
A fast d.f.t. algorithm using complex integer transforms

For certain large transform lengths, Winograd's algorithm for computing the discrete Fourier transform (d.f.t.) is extended considerably. This is accomplished by performing the cyclic convolution, required by Winograd's method, by a fast transform over certain complex integer fields developed previously by the authors. This new algorithm requires fewer multiplications than either the standard fast Fourier transform (f.f.t.) or Winograd's more conventional algorithm.
Determination of Single-Bond Forces from Contact Force Variances in Atomic Force Microscopy

Atomic force microscopy contact forces are shown to obey a Poisson distribution, so that the ratio of their variance to mean gives the force of a single chemical bond between the tip and sample. The derived single-bond force was able to distinguish nominal van der Waals interactions (60 ± 3 pN) from hydrogen-bond interactions (181 ± 35 pN) between atomic force microscope tips and gold and mica surfaces, respectively. This technique greatly reduced sampling time and sample wear, allowed quantitative use of low-resolution force data from a commercially available instrument, and detected important chemical differences between surface functional groups on the samples. These experiments constitute an important step in obtaining chemically specific information in atomic force microscopy.
Matrix Infrared Spectra and Density Functional Calculations for GaNO, InNO, and TlNO

Laser-ablated Ga, In, and Tl atoms react with NO during condensation in excess argon at 10 K to give one major product, which absorbs at 1578.5 cm-1 for Ga, 1524.9 cm-1 for In, and 1454.6 cm-1 for Tl. Infrared spectra of 14N16O, 15N16O, 15N18O, and mixed isotopic samples show that this product is the metal nitrosyl MNO. Density functional calculations provide good agreement for 3Σ- GaNO and InNO, but higher level MP2 calculations are required to explain the bent structure and decreased N−O frequency for 3A‘ ‘ TlNO. Model DFT calculations are also reported for Li[NO] and Li[NO]Li.
Acute Prolonged Confusion in Later Life as an Ictal State

Six patients ranging in age from 42 to 69 with no prior history of seizure disorder presented an acute prolonged or intermittent confusional state, with or without psychotic symptoms, as an ictal manifestation. The EEGs demonstrated protracted generalized spike and wave discharges, but full diagnostic evaluation disclosed no evident cause for the seizures. All promptly responded to small amounts of intravenous diazepam and subsequent oral phenytoin and phenobarbital. Three of the six patients had focal spike or sharp wave discharges on EEGs recorded subsequently, suggesting that the episodes may reflect secondary generalized seizures in some cases. These cases do not fit in the classic category of petit mal status and appear to be a distinct entity.
Enhanced Ion mobility in Aluminosilicate/Polysiloxane Network Polyelectrolytes

A new series of polysiloxane-based single-ion conductors was prepared. These contain solvating oligoether sidechains and covalently linked aluminosilicate or alkoxy/siloxy-aluminate anions attached to the polysiloxane backbone. Of these two systems, the polymers containing aluminosilicate [(SiO)4Al]− anions show higher room temperature conductivities (10−6 S/cm) than those with alkoxy/siloxyaluminate [(SiO)2(CH2O)2A1]− anions (10−7 S/cm). The incorporation of longer covalent tethers between the alkoxy/siloxyaluminate anion and the polymer backbone results in enhanced room temperature conductivities at high ion loadings. Differential scanning calorimetry data provide a rationale for the high conductivity.
“Arapesh Warfare”: Reo Fortune's Veiled Critique of Margaret Mead's Sex and Temperament

ABSTRACT In Sex and Temperament (1935), Margaret Mead depicted the Mountain Arapesh as a nurturing, peace-loving people. But Mead's second husband and fieldwork partner, Reo Fortune, disagreed with this in a 1939 article, “Arapesh Warfare,” which presented evidence that before pacification Arapesh society countenanced warfare. Here we show that “Arapesh Warfare” also contains a submerged argument against Mead's personal integrity and ethnographic authority. Sex and Temperament had its own personal subtext, and Fortune responded to it by mobilizing rhetorical strategies drawn from an Arapesh framework of speaking. Our analysis provides insight into Fortune's position in an anthropological disagreement that has been seen primarily from Mead's perspective—when it has been seen at all. Fortune's peculiar approach also speaks to a limitation on reflexivity in anthropology: the illegitimacy of criticizing personal motives in cases of ethnographic dispute, although we know scholarly works are always suffused with their authors’ personal histories and perspectives.
Boundary element method analysis of thermoelastic deformation in nonhomogeneous media

Abstract This paper presents a boundary element method (BEM) formulation and numerical implementation of thermoelasticity problems in nonhomogeneous media. The formulation uses the known kernels of the displacement equations for elasticity problems in homogeneous media. This formulation leads to a domain integral containing the unknown displacement field in addition to the usual boundary integrals with displacements and tractions. An iterative scheme is used to determine the displacement fields. Numerical results are presented for some illustrative plane strain problems. The iterative scheme is shown to converge rapidly for these problems with moderate temperature gradients. The BEM results are compared with results from the finite element method (FEM) for these problems, and also with exact solutions whenever possible.
Utilization and outcomes of surgical gastrostomies and jejunostomies in an era of percutaneous endoscopic gastrostomy: a population-based study.

Objective To determine the indications for use of surgical gastrostomy (SG) and surgical jejunostomy (SJ) as feeding tubes, the complications, and the trends in the use of SG and SJ after the introduction of percutaneous endoscopic gastrostomy (PEG) at our institution in 1981. Design We conducted a retrospective, population-based cohort study of residents of Olmsted County, Minnesota, who received surgically placed feeding tubes between 1976 and 1989. Material and Methods The medical records of all Olmsted County residents with surgical placement of a feeding tube during the designated study period were reviewed, and underlying conditions, complications, and survival were analyzed. Results Of 77 adult patients (mean age, 66 years; 48% women), 54 underwent SG and 23 had SJ. General anesthesia was used in 42 patients (55%). The indications for SG or SJ were stroke in 23 patients, cancer in 19, other central nervous system-related conditions in 16, and other conditions in 19. Among the numerous comorbid conditions, pulmonary disease (N = 44) and cardiac disease (N = 32) were most frequent. The median duration of follow-up was 181 days. Complications occurred in 31 of 54 patients (57%) with SG and in 13 of 23 (57%) with SJ. Of the 117 complications, 15% were considered major. Twenty patients (26%) resumed eating. Survival at 1, 6, and 12 months was 79%, 49%, and 36%, respectively. Most deaths were due to the disease for which the feeding tube had been placed. In a Cox proportional hazards regression analysis, only age and hypoxemia were found to be significantly associated with survival. Hypoxemia, type of tube, central nervous system disease as indication for procedure, and previous aspiration were associated with failure to resume eating ( P Conclusion Patients who require enteral feeding tubes have multiple comorbid conditions that have a major influence on the outcome. The overall incidence of feeding tube placement increased after the introduction of PEG. In patients who require longterm enteral nutrition and are unable to have a feeding tube placed percutaneously, surgically placed feeding tubes have outcomes similar to those reported for patients with PEG.
Volcanic eruption clouds and the thermal power output of explosive eruptions

Abstract The maximum height attained by a volcanic eruption cloud is principally determined by the convective buoyancy of the mixture of volcanic gas + entrained air + fine-sized pyroclasts within the cloud. The thermal energy supplied to convection processes within an eruption cloud is derived from the cooling of pyroclastic material and volcanic gases discharged by an explosive eruption. Observational data from six recent eruptions indicates that the maximum height attained by volcanic eruption clouds is positively correlated with the rate at which pyroclastic material is produced by an explosive eruption (correlation coefficient r = + 0.97). The ascent of industrial hot gas plumes is also governed by the thermal convection process. Empirical scaling relationships between plume height and thermal flux have been developed for industrial plumes. Applying these scaling relationships to volcanic eruption clouds suggests that the rate at which thermal energy is released into the atmosphere by an explosive eruption increases in an approximately linear manner as an eruption's pyroclastic production rate increases.
Separation of Multisized Drug Suspensions into Narrow Distributions by Centrifugal Elutriation

A centrifugal elutriator rotor was used to separate suspensions of micronized hydrocortisone acetate and prednisolone acetate. Up to five distinct particle fractions could be isolated from a single parent suspension, and reasonable reproducibility was exhibited between various elutriator runs. Arithmetic means and associated standard deviations, based on volume, were calculated for each isolated fraction. These data demonstrate the narrowness and uniqueness of each fraction. The particle-size data show an apparent log-normal distribution for each isolate. The uniqueness of each fraction also was demonstrated by dissolution experiments where Fraction 1, the smallest fraction of prednisolone acetate, dissolved much more rapidly than Fraction 4, the largest fraction. The substantial difference in dissolution behavior of these two fractions of prednisolone acetate powder was biopharmaceutically significant.
A Case Study of the Scholarship of Teaching and Learning in a Food Safety Class

Food safety is a concern in society today and is an important part of hospitality and culinary students' education. However, research has shown that coursework in food safety does not necessarily influence actual food safety behaviors. This article describes a Scholarships of Teaching and Learning (SoTL) project using an alternative teaching and learning strategy for food safety education. Attitudes toward food safety were measured before and after the completion of the project, and significant differences were found. The project involved the students in development of an observational tool for food-handling behaviors that was perceived positively and merits further study.
An approach to defect detection in materials characterized by complex textures

Abstract This paper describes an expert system which detects and categorizes defects in digitized images of materials characterized by complex texture patterns. The system performs two major tasks: image segmentation and defect classification. Segmentation is done in two steps. First, individual texture samples are isolated. Second, a pyramid linking scheme is used to locate defects in each sample. This pyramid linking scheme can be fine-tuned to various textures and to the size of the defects to be detected. The defect classification method is dependent on the material being analyzed. This paper describes a hierarchical defect classification scheme for analyzing wood. The hierarchy incorporates a shape descriptor, size, and textural descriptors of individual defects. The system has been tested on parquet samples where it successfully detects and classifies defects.
Cochlear implant electrode failure secondary to silicone touch-up during device manufacturing.

Study design Retrospective case report. Setting Tertiary referral cochlear implant center. Patient A 21-year-old woman was implanted with Advanced Bionics HiFocus Clarion device without complication. Five years later, the patient presented with dizziness, fluctuating implant performance, and facial pain. Intervention Surgical exploration revealed a torn electrode silicon casing in conjunction with scar contraction bending the electrode against bony facial nerve canal at the facial recess. Suspension of the electrode such that the damaged portion was not in contact with mastoid cavity led to temporary resolution of symptoms. Explantation and reimplantation procedures were carried out 2 months later. Results Postexplantation device analysis by the manufacturer demonstrated silicone touch-up at the site of failure. Six years since reimplantation, the patient has remained symptom-free. It is very likely that the touch-up silicon weakened the electrode and, in conjunction with chronic scar contraction, led to the tear on the silicon casing. Conclusion Isolated cochlear implant electrode failure is a rare but possible long-term complication in older generation devices. The author reports 1 case of implant device failure partly because of silicon touch-up that was applied at the location of electrode failure during its manufacturing process.
Blind restoration of very-high-ISO photos via low-rank methods

We propose a new algorithm for blind restoration of very-high-ISO photos. Unlike previous methods that sequentially tackle the problem of noise estimation and image denoising, our approach alternatively refines the estimates of latent image and noise level function (NLF). We rigorously show how the existing low-rank based modeling of image prior can be extended to incorporate spatially inhomogeneous and signal-dependent noise. We develop a generalization of singular-value thresholding technique by making the thresh-old/regularization parameter doubly adaptive - adaptive to both local signal and noise variance estimates. Our experimental results have shown that the proposed auto-denoising algorithm is capable of achieving visually pleasant restoration of photos with ISO settings of above 6400 for a wide range of brand cameras and at a moderate computational cost.
Edge-driven convection

We consider a series of simple calculations with a step-function change in thickness of the lithosphere and imposed, far-field boundary conditions to illustrate the influence of the lithosphere on mantle flow. We consider the effect of aspect ratio and far-field boundary conditions on the small-scale flow driven by a discontinuity in the thickness of the lithosphere. In an isothermal mantle, with no other outside influences, the basic small-scale flow aligns with the lithosphere such that there is a downwelling at the lithospheric discontinuity (edge-driven flow); however, the pattern of the small-scale flow is strongly dependent on the large-scale thermal structure of a much broader area of the upper mantle. Long-wavelength temperature anomalies in the upper mantle can overwhelm edge-driven flow on a short timescale; however, convective motions work to homogenize these anomalies on the order of 100 million years while cratonic roots can remain stable for longer time periods. A systematic study of the effect of the boundary conditions and aspect ratio of the domain shows that small-scale, and large-scale flows are driven by the lithosphere. Edge-driven flow produces velocities on the order of 20 mm/yr. This is comparable to calculations by others and we can expect an increase in this rate as the mantle viscosity is decreased.
An algorithm for optimal minimax routing in ATM networks

Asynchronous Transfer Mode (ATM) has been adopted by the CCITT as the transport mode in which Broadband ISDN will be based. In this paper, we formulate the problem of routing cells in an ATM network as an optimization problem. The objective is to minimize the largest cell loss probability among all links. The constraints correspond to a multicommodity network flow problem with gains. An algorithm to determine a global optimal flow assignment is presented. The minimax routing algorithm was implemented and tested on several sample networks. The computational experiments show that the algorithm is computationally efficient.
Simultaneous topography imaging and molecular recognition with low crosstalk and high sensitivity

Atomic force microscope has been used to recognize biomolecules through a functionalize tip. In order to achieve simultaneous topography imaging and molecular recognition, existing method such as PicoTREC (commercialized by Agilent Inc.) extracts the topography image from the lower amplitude of the cantilever oscillation while extracts recognition image from the upper amplitude of the cantilever oscillation. To avoid crosstalk between topography and recognition images, PicoTREC requires using cantilever with small quality factor (Q≈1). Such low Q, however, results in low force sensitivity, thus a large tip-sample interaction force during imaging, which is destructive to the soft biological samples. In this paper, we propose an innovative method for simultaneous topography imaging and molecular recognition using cantilever with high Q but with minimized crosstalk. For cantilever with large quality factor (Q>10) in liquid, the upper part and lower part of the cantilever's oscillation becomes symmetric. The topography information that exists in the lower amplitude of the deflection signal also exists in the upper amplitude. Because of the symmetry of the deflection signal, the topography information in the upper amplitude can be cancelled by the lower amplitude. However, the control system will conversely respond to the decrease of the amplitude caused by the molecule binding. So taking use of the lower amplitude, the topography crosstalk in the upper amplitude can be cancelled and the molecule recognition information can be kept. So using this method, high-Q cantilever can be used for simultaneous topography and molecular recognition without crosstalk. The high-Q cantilever will result in high-force sensitivity that will be less destructive to the soft biological samples. This technique will make the simultaneous topography imaging and molecular recognition possible on soft biological sample surfaces, such as the cell membrane. In this paper, the simulation is utilized to demonstrate the principle of our proposed method, and then initial experiments are also performed to validate our method.
Dinitrogen chemistry from trigonally coordinated iron and cobalt platforms.

The chemistry of low-valent iron and cobalt has been slow to develop, due largely in part to a lack of ligand scaffolds that can stabilize these species. Using the anionic tris(phosphino)borate ligand, [PhB(CH_2PiPr_2)_3]-, we have stabilized reactive complexes of the type [P_3M-L] where L can be varied from weakly-donating π-acidic ligands (e.g. N_2), to strongly π-basic ligands where multiple bonding occurs between the metal and L (e.g. NR ^2-). In addition to stabilizing a broad range of ligand types in a variety of oxidation states, the [P_3M] template has been shown to mediate the coordination and activation of dinitrogen on both iron and cobalt. The reaction chemistry of the [P_3M-L] scaffolds will be presented in addition to synthetic strategies targeting high-valent species (M^(IV), L=N ^3-).
Sequential function approximation for the solution of differential equations

A computational method for the solution of differential equations is proposed. With this method an accurate approximation is built by incremental additions of optimal local basis functions. The parallel direct search software package (PDS), that supports parallel objective function evaluations, is used to solve the associated optimization problem efficiently. The advantage of the method is that, although it resembles adaptive methods in computational mechanics, an a priori grid is not necessary. Moreover, the traditional matrix construction and evaluations are avoided. Computational cost is reduced while efficiency is enhanced by the low-dimensional parallel-executed optimization and parallel function evaluations. In addition, the method should be applicable to a broad class of interpolation functions
Fatty acid metabolism, the central nervous system, and feeding.

A potential role for fatty acid metabolism in the regulation of energy balance in the brain or in the periphery has been considered only recently. Fatty acid synthase (FAS) catalyzes the synthesis of long-chain fatty acids, whereas the breakdown of fatty acids by β-oxidation is regulated by carnitine palmitoyltransferase-1, the rate-limiting enzyme for the entry of fatty acids into the mitochondria for oxidation. While the question of the physiological role of fatty acid metabolism remains to be resolved, studies indicate that inhibition of FAS or stimulation of carnitine palmitoyltransferase-1 using cerulenin or synthetic FAS inhibitors reduces food intake and incurs profound and reversible weight loss. Several hypotheses regarding the mechanisms by which these small molecules mediate their effects have been entertained. Centrally, these compounds alter the expression of hypothalamic neuropeptides, generally reducing the expression of orexigenic peptides. Whether through central, peripheral, or combined central and peripheral mechanisms, these compounds also increase energy consumption to augment weight loss. In vitro and in vivo studies indicate that at least part of C75's effects is mediated by modulation of adenosine monophosphate-activated protein kinase, a member of an energy-sensing kinase family. These compounds, with chronic treatment, also alter gene expression peripherally to favor a state of enhanced energy consumption. Together, these effects raise the possibility that pharmacological alterations in fatty acid synthesis/degradation may serve as a target for obesity therapeutics.
Territorial Status-Quo Between the Big-Headed Ant (Hymenoptera: Formicidae) and the Formosan Subterranean Termite (Isoptera: Rhinotermitidae)

Abstract The big-headed ant, Pheidole megacephala (Fabr.) (Hymenoptera: Formicidae) and the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) are 2 invasive species in south Florida, and both have a major economic and ecological impact. Because both species are often associated with man-made structures, we investigated how the 2 species interacted when their tunneling system connected, to determine if the big-headed ant had the ability to predate or displace subterranean termite colonies. It was previously suggested that the 2 species had a predator-prey interaction. However in this study we showed that C. formosanus can defend its territory against P. megacephala with minimal loss, and we therefore re-described their interaction as a status quo for habitat competition. It is unlikely that a competitive displacement would take place between C. formosanus and P. megacephala because of their ability to successfully defend their respective nests.