cssi/SciSciGPT-SciSciNet huggingface dataset:
Leadership Training in Medicine-12 Years of Experience From the Feagin Leadership Program.

INTRODUCTION Increasingly, physicians find themselves in demanding leadership positions. However, leadership education for medical trainees remains lacking with most physicians reporting that they are ill-equipped to tackle the challenges of leadership. Here, we set out to describe the Feagin Leadership Program (FLP) and assess its reception and impact on trainees over the past 12 years. MATERIALS AND METHODS During the 1-year FLP, selected scholars from Duke University, Wake Forest University, and the University of North Carolina participate in five leadership sessions, individual coaching, a leadership forum, and a multidisciplinary team-based capstone project. A 28-question survey with six optional free-response questions was distributed to the Feagin Alumni Network, and descriptive statistics were assessed. RESULTS Since its founding, 212 scholars have graduated from the FLP and 117 (55%) alumni have gone on to surgical specialties. A survey was distributed among all Feagin alumni. A total of 56 (26%) surveys were completed. Forty-three percent (n = 24) had held at least one leadership position since completing the FLP. When asked about the impact of their experience, 96% (n = 54) said that the program encouraged them to pursue a position of leadership within their field, 95% (n = 53) stated that it prepared them for such a position, and 93% (n = 52) stated that the program positively influenced their decision to be involved with current or future positions of leadership. CONCLUSIONS Over the last 12 years, the FLP has demonstrated a high perceived impact on personal growth, leadership proficiency, and the decision to pursue leadership positions in medicine. The current dearth of leadership education for surgical trainees can best be addressed with models such as the FLP, with adoption benefiting medical trainees, the medical community, and patients they serve.
Algometry in the daily practice of pain management.

Purpose: This is a review article to update the clinical applications of pressure pain sensitivity (PPS) measurement by pressure algometry (P A) [1,2] Basic procedures: The basic literature on pressure algometry has been reviewed with emphasis on new developments. The author's and his co-workers' experience with P A, extending several years, are also included along with some unpublished research results. Findings: The high reliability and validity of P A for quantification of PPS has been proven by several authors. The specificity and sensitivity of PAin detection of trigger points (TrPs) is also very good. PA is also useful in evaluation of treatment results. PA can document the decreased PPS after 'preinjection (regional) blocks' administered prior to trigger point injections (TPIs). A study of ten patients with failed back surgery included 20 muscles. PA documented long-term improvement (150 days) which corresponded to a decrease in pain rating. Treatment consisted of needling and infiltration of the entire trigger point (TrP) extending to taut band. Another study showed that physicians were unable to produce 4 kg of pressure, which is critical for diagnosis of fibromyalgia. Conclusions: Quantification of fibromyalgia diagnosis by PA is necessary for abnormal tenderness (pain on 4 kg pressure). The critical pressure for TrP, tender spots is a pressure pain threshold lower by 2 kg/cm2 relative to a normally sensitive corresponding control point. © 1997 Elsevier Science Ireland Ltd.
Pseudomonas syringae enhances herbivory by suppressing the reactive oxygen burst in Arabidopsis

Plant-herbivore interactions have evolved in the presence of plant-colonizing microbes. These microbes can have important third-party effects on herbivore ecology, as exemplified by drosophilid flies that evolved from ancestors feeding on plant-associated microbes. Leaf-mining flies in the genus Scaptomyza, which is nested within the paraphyletic genus Drosophila, show strong associations with bacteria in the genus Pseudomonas, including Pseudomonas syringae. Adult females are capable of vectoring these bacteria between plants and larvae show a preference for feeding on P. syringae-infected leaves. Here we show that Scaptomyza flava larvae can also vector P. syringae to and from feeding sites, and that they not only feed more, but also develop faster on plants previously infected with P. syringae. Our genetic and physiological data show that P. syringae enhances S. flava feeding on infected plants at least in part by suppressing anti-herbivore defenses mediated by reactive oxygen species.
Bankruptcy and Debt: A New Model for Corporate Reorganization

Two of the core determinations made in a reorganization proceeding under chapter 11 of the Bankruptcy Code' are simply stated: Who gets how much? What will the new capital structure be? To resolve these simply stated questions of valuation and recapitalization, bankruptcy courts loosely oversee a lengthy bargaining process that is widely thought to be cumbersome, costly, and complex. The strain of extended financial stress results in lost sales when customers seek a more secure supply source, in consumption of valuable management time spent resolving financial difficulties, and in forgone opportunities to obtain new projects. Additional costs are borne by the employees, customers, and suppliers of the bankrupt company, as well as the comnunities in which it operates. Furthermore, while contraction of the bankrupt firm is usually in order, parts of the firm may sometimes be liquidated even though liquidation value is less than operational value. Finally, the firm often emerges from reorganization with an unnecessarily complex capital structure. Such a complex capital structure can cause the reorganized firm to adopt poor operational strategies, prevent it from raising new capital, and pose a barrier to a healthy merger.
Reconciliation and Nonrepetition: A New Paradigm for African-American Reparations

The contemporary paradigm for African-American reparations fundamentally fails to address what should be its most vital component. Of the three essential elements of a successful reparations campaign - apology, award, and non-repetition through reconciliation - the most vital is non-repetition. In past "successful" reparations campaigns, the offending parties have issued apologies and awards, but have neither challenged nor dismantled the attitudes or infrastructures from which wrongful acts emerged, leaving open the likelihood of wrongful acts occurring again. Any campaign that neglects the non-repetition element runs the risk of strengthening the status quo. In this article, Professor Burkett argues that in order for a reparations campaign to be a true success for African-Americans, it must include a non-repetition element. To do so, the reparations movement must embrace a reconciliation model that is forward-looking and concerned with the methods of deterring future bad acts for ultimate, complete, and successful repair. In the current discourse on African-American reparations, Professor Burkett argues, non-repetition through reconciliation is woefully underemphasized. The incorporation of the non-repetition element is particularly important in the American context. From the nation's earliest days, the American political and economic landscape has evolved in a particularly pernicious manner, creating and entrenching a racial and economic hierarchy that persistently subjugates African-Americans and other of-color and low-income communities. Professor Burkett argues that in this context a multi-racial, multi-ethnic and cross-class reconciliation model is vital to the success of the African-American campaign. This broad-based approach, the author maintains, is the only way to ensure non-repetition.
Does Movie or Video Game Violence Predict Societal Violence? It Depends on What You Look at and When

This article presents 2 studies of the association of media violence rates with societal violence rates. In the first study, movie violence and homicide rates are examined across the 20th century and into the 21st (1920–2005). Throughout the mid-20th century small-to-moderate correlational relationships can be observed between movie violence and homicide rates in the United States. This trend reversed in the early and latter 20th century, with movie violence rates inversely related to homicide rates. In the second study, videogame violence consumption is examined against youth violence rates in the previous 2 decades. Videogame consumption is associated with a decline in youth violence rates. Results suggest that societal consumption of media violence is not predictive of increased societal violence rates.
Hydroxamate Recognition During Iron Transport from Hydroxamate-Iron Chelates

Kinetics of radioactive iron transport from three structurally different secondary hydroxandate-iron chelates (schizokineniron, produced by Bacillus megaterium ATCC 19213; Desferaliron, produced by an actinomycete; and aerobactin- iron, produced by Aerobacter aerogenes 62-1) revealed that B. megateriurm SK 11 (a mutant that cannot synthesize schizokinen) has a specific transport system for utilization of ferric hydroxamates with a recognition capacity based on the chemical structure of the hydroxamate. Both Desferal and schizokinen enhanced iron uptake in this organism; however, Desferal-iron delivered only one-sixth the level of iron incorporated from the schizokinen-iron chelate. Desferaliron did not generate the rapid rates of iron transport noted with schizokinen-iron at elevated iron concentrations. Assays containing large excesses of either iron- free Desferal or iron-free schizokinen suggested that the iron-free hydroxamate may compete with the ferric hydroxamate for acceptance by the transport system although the system has greater affinity for the iron chelate. Aerobactin-iron did not stimulate iron uptake in B. megaterium SK 11 and aerobactin inhibited growth of this organism, indicating that B. megateriuni SK 11 cannot efficiently process the aerobactin-iron chelate. (auth)
A load balancing strategy for prioritized execution of tasks

Load balancing is a critical factor in achieving optimal performance in parallel applications where tasks are created in a dynamic fashion. In many computations, such as state space search problems, tasks have priorities, and solutions to the computation may be achieved more efficiently if these priorities are adhered to in the parallel execution of the tasks. For such tasks, a load balancing scheme that only seeks to balance load, without balancing high priority tasks over the entire system, might result in the concentration of high priority tasks (even in a balanced-load environment) on a few processors, thereby leading to low priority work being done. In such situations a load balancing scheme is desired which would balance both load and high priority tasks over the system. The authors describe the development of a more efficient prioritized load balancing strategy. >
Subfractionation and Analysis of the Cell Envelope (Lipo)polysaccharides of Mycobacterium tuberculosis

The cell envelope of Mycobacterium tuberculosis, the causative agent of tuberculosis in humans, is the source of carbohydrates of exceptional structure which play essential roles in the physiology of the bacterium and in its interactions with the host during infection. Much of what is known about their biosynthesis was derived from the phenotypic analysis of knockout or conditional knockout mutants of mycobacteria generated by random or specific insertional mutagenesis. Here, we describe the current techniques used to subfractionate M. tuberculosis cells and investigate major quantitative and qualitative changes in their cell envelope (lipo)polysaccharides.
Structure, phase transitions and ionic conductivity of K3NdSi6O15·xH2O. I. α-K3NdSi6O15·2H2O and its polymorphs

Hydrothermally grown crystals of α-K3NdSi6O15·2H2O, potassium neodymium silicate, have been studied by single-crystal X-ray methods. The compound crystallizes in space group Pbam, contains four formula units per unit cell and has lattice constants a = 16.008 (2), b = 15.004 (2) and c = 7.2794 (7) A, giving a calculated density of 2.683 Mg m−3. Refinement was carried out with 2161 independent structure factors to a residual, R(F), of 0.0528 [wR(F2) = 0.1562] using anisotropic temperature factors for all atoms other than those associated with water molecules. The structure is based on highly corrugated (Si2O52−)∞ layers which can be generated by the condensation of xonotlite-like ribbons, which can, in turn, be generated by the condensation of wollastonite-like chains. The silicate layers are connected by Nd octahedra to form a three-dimensional framework. Potassium ions and water molecules are located in interstitial sites within this framework, in particular, within channels that extend along [001]. Aging of as-grown crystals at room temperature for periods of six months or more results in an ordering phenomenon that causes the length of the c axis to double. In addition, two phase transitions were found to occur upon heating. The high-temperature transformations, investigated by differential scanning calorimetry, thermal gravimetric analysis and high-temperature X-ray diffraction, are reversible, suggesting displacive transformations in which the layers remain intact. Conductivity measurements along all three crystallographic axes showed the conductivity to be greatest along [001] and further suggest that the channels present in the room-temperature structure are preserved at high temperatures so as to serve as pathways for easy ion transport. Ion-exchange experiments revealed that silver can readily be incorporated into the structure.
Computational microscopy in embryo imaging

The growth of computing power has greatly improved our ability to extract quantitative information about complicated three-dimensional structures from microscope images. New hardware techniques are also being developed to provide suitable images for these tasks. However, a need exists for synthetic data to test these new developments. The work reported here was motivated by studies of embryo health, but similar needs exist across the field of microscopy. We report a rigorous computer model, based on Maxwell’s equations, that can produce the required synthetic images for bright-field, differential interference contrast, interferometric imaging, and polarimetric imaging. After a description of the algorithm, sample results are presented, followed by a discussion of future plans and applications.
Age-related variation in the DNA-repair synthesis after UV-C irradiation in unstimulated lymphocytes of healthy blood donors

Abstract UV-C light-induced DNA-repair synthesis was studied in unstimulated lymphocytes of 51 healthy blood donors aged between 17 and 74 years. Repair synthesis was measured by the incorporation of [ 3 H]thymidine after a 2-h incubation period in the presence of 2 mM hydroxyurea. The evaluation included (1)the spontaneous DNA-synthesis in unirradiated lymphocytes with and without hydroxyurea, (2) the DNA-repair synthesis in lymphocytes irradiated with UV-light. The interindividual variation was significantly higher than the methodological variation ascertained in 24 persons in whom 2 determinations were carried out. In blood donors aged between 17 and 39 years, the spontaneous DNA synthesis, both with and without hydroxyurea, was significantly lower than in older individuals The DNA-repair synthesis was dependent on the dose of UV-C light between 2 and 16 J/M 2 . There were no significant differences in DNA-repair synthesis in the age range 17–74 years. The variations in rate of DNA-repair synthesis (greater or lesser degree of [ 3 H]thymidine incorporation beyond the 99% confidence range) were wider in older (44–74 years), than in younger individuals.
Identification of a renal-specific oxido-reductase in newborn diabetic mice

Aldose reductase (ALR2), a NADPH-dependent aldo-keto reductase (AKR), is widely distributed in mammalian tissues and has been implicated in complications of diabetes, including diabetic nephropathy. To identify a renal-specific reductase belonging to the AKR family, representational difference analyses of cDNA from diabetic mouse kidney were performed. A full-length cDNA with an ORF of 855 nt and yielding a ≈1.5-kb mRNA transcript was isolated from a mouse kidney library. Human and rat homologues also were isolated, and they had ≈91% and ≈97% amino acid identity with mouse protein. In vitro translation of the cDNA yielded a protein product of ≈33 kDa. Northern and Western blot analyses, using the cDNA and antirecombinant protein antibody, revealed its expression exclusively confined to the kidney. Like ALR2, the expression was up-regulated in diabetic kidneys. Its mRNA and protein expression was restricted to renal proximal tubules. The gene neither codistributed with Tamm–Horsfall protein nor aquaporin-2. The deduced protein sequence revealed an AKR-3 motif located near the N terminus, unlike the other AKR family members where it is confined to the C terminus. Fluorescence quenching and reactive blue agarose chromatography studies revealed that it binds to NADPH with high affinity (KdNADPH = 66.9 ± 2.3 nM). This binding domain is a tetrapeptide (Met-Ala-Lys-Ser) located within the AKR-3 motif that is similar to the other AKR members. The identified protein is designated as RSOR because it is renal-specific with properties of an oxido-reductase, and like ALR2 it may be relevant in the renal complications of diabetes mellitus.
What is the best expression of the second‐order sum‐over‐state perturbation energy based on the Hartree‐Fock wavefunction?

We have improved in a stepwise manner the second‐order sum‐over‐state perturbation energy which is written in the infinite sum over singly excited configurations based on the Hartree‐Fock (HF) zeroth‐order wavefunction. Firstly, the conventional equation [Eq. (10)] is shown to be dependent on the unitary transformations among singly excited configurations. The best unitary transformation gives the Tamm‐Dancoff (or singly excited configuration interaction) approximation of the excited states. The resultant equation [Eq. (25)] includes in a simple form all of the coupling terms between different singly excited configurations. As a restrictive special case, this unitary transformation leads to the modified HF orbitals of Silverstone‐Huzinaga and Morokuma‐Iwata. Secondly, it is shown that the second‐order energy of the coupled HF theory can also be written in a simple sum‐over‐state perturbation formula. The resultant equation [Eq. (50)] does not require an iterative solution. Moreover, it is shown that this is the best possible expression of the second‐order energy based on the HF zeroth‐order wavefunction. As a restrictive special case, this treatment produces new improved modified HF operators which are thought to be superior to those hitherto given.
Proteasome-mediated degradation of the vitamin D receptor (VDR) and a putative role for SUG1 interaction with the AF-2 domain of VDR

The AF-2 helix of nuclear receptors is essential for ligand-activated transcription, and it may function to couple the receptor to transcriptional coactivator proteins. This domain also contacts components of the proteasome machinery, suggesting that nuclear receptors may be targets for proteasome-mediated proteolysis. In the present study, we demonstrate that mSUG1 (P45), a component of the 26S proteasome, interacts in a 1,25-(OH)2D3–dependent manner with the AF-2 domain of the vitamin D receptor (VDR). Furthermore, treatment of ROS 17/ 2.8 osteosarcoma cells with the proteasome inhibitors MG132 or β-lactone increased steady-state levels of the VDR protein. In the presence cycloheximide (10 μg/ ml), the liganded VDR protein was degraded with a half-life of approximately 8 h, and this rate of degradation was completely blocked by 0.05 mM MG132. The role of SUG1-VDR interaction in this process was investigated in transient expression studies. Overexpression of wild-type mSUG1 in ROS17/ 2.8 cells generated a novel proteolytic VDR fragment of approximately 50 kDa, and its production was blocked by proteasome inhibitors or by a nonhydrolyzable ATP analog. Parallel studies with SUG1(K196H), a mutant that does not interact with the VDR, did not produce the 50 kDa VDR fragment. Functionally, expression of SUG1 in a VDR-responsive reporter gene assay resulted in a profound inhibition of 1,25-(OH)2D3–activated transcription, while expression of SUG1(K196H) had no significant effect in this system. These data show that the AF-2 domain of VDR interacts with SUG1 in a 1,25-(OH)2D3–dependent fashion and that this interaction may target VDR to proteasome-mediated degradation as a means to downregulate the 1,25-(OH)2D3–activated transcriptional response. J. Cell. Biochem. 71:429–440, 1998. © 1998 Wiley-Liss, Inc.
Combining Low and High Mass Ion Accumulation for Enhancing Shotgun Proteome Analysis by Accurate Mass Measurement

A simple procedure is described that increases sensitivity and dynamic range for the analysis of a proteome batch digest by FT-ICR mass spectrometry. Ions at the low and high mass ranges are preferentially collected using two different sets of tuning conditions. By combing data collected using tuning conditions that favor low mass (m/z 2000) ions, 277 proteins are identified for a whole cell lysate of Methanococcus maripaludis in a single HPLC-MALDI FT-ICR mass spectrometry experiment, a 70% improvement compared with previous analyses using a wide mass range acquisition. This procedure improves the detection of low abundance ions and thereby increases the range of proteins that are observed. Because the observed mass range is effectively narrower for each spectrum, mass calibration is more accurate than for the standard method that provides a wide range of masses. The trap plate potential on the analyzer cell may be set to a higher value than used for wide mass range measurements, increasing the ion capacity of the analyzer cell and extending the dynamic range, while still maintaining mass accuracy.
Disclinated states in nematic elastomers

Abstract We present a theory for uniaxial nematic elastomers with variable asphericity. As an application of the theory, we consider the time-independent, isochoric radial expansion of a right circular cylinder. Numerical solutions to the resulting differential equation are obtained for a range of radial expansions. For all expansions considered, there exists an isotropic core of material surrounding the cylinder axis where the asphericity vanishes and in which the polymeric chains are shaped as spherical coils. This region, corresponding to a disclination of strength +1 along the axis, is bounded by a narrow transition layer across which the asphericity increases rapidly and attains a non-trivial positive value. The material thereby becomes anisotropic away from the disclination so that the polymeric chains are shaped as ellipsoidal coils of revolution prolate about the cylinder radius. In accordance with the area of steeply changing asphericity between isotropic and anisotropic regimes, a marked drop in the free-energy density is observed. The boundary of the disclination core is associated with the location of this energy drop. For realistic choices of material parameters, this criterion yields a core on the order of 10 −2 μm , which coincides with observations in conventional liquid-crystal melts. Also occurring at the core boundary, and further confirming its location, are sharp transitions in the behavior of the constitutively determined contributions to the deformational stress and a change in the pressure. Furthermore, the constitutively determined contribution to the orientational stress is completely concentrated at the core boundary. The total energy shows a definitive preference for disclinated states.
Association of anthropometric measures with risk of diabetes and cardiovascular disease in Hispanic and Caucasian adolescents.

Abstract Background Hispanics are disproportionately affected by the obesity epidemic in the United States. Obesity is a primary risk factor for the development of cardiovascular disease (CVD) and Type 2 diabetes, which are problematic in Hispanic adults. There are limited data relating obesity status in Hispanic adolescents to diabetes and CVD risk. Methods We studied 115 lean and obese adolescents (89 Hispanic, 26 Caucasian), ranging in body mass index (BMI) from 15 to 52 kg/m 2 . We assessed the relationships between four anthropometric indices of obesity and risk factors for Type 2 diabetes (insulin (INS), glucose (GLU)), and CVD (total cholesterol, triglycerides, HDL, and systolic (SBP) and diastolic (DBP) blood pressure). Results All anthropometric indices were positively correlated with total cholesterol, triglycerides, log(INS), GLU, SBP, and DBP, and negatively correlated with HDL. Correlations and multiple regression analyses indicated that weight and waist circumference (WC) were generally the best single predictors of disease risk. Using more than one anthropometric measure in multiple regression did not improve predictions of risk over using a single predictor. Conclusions These results indicate that overweight adolescents (particularly Hispanics) are at risk for developing Type 2 diabetes and CVD, and that WC and weight are useful for identifying those at particular risk.
Secular variation of earth's gravitational harmonic J2 coefficient from Lageos and nontidal acceleration of earth rotation

Analysis of 5.5 years of Lageos satellite range data reveal significant residual nodal signatures: an acceleration and annual and semiannual periods. These signatures primarily reflect variations in the zonal gravitational harmonic J2 coefficient and hence the polar moment of inertia. The implied decrease of J2 = -3 x 10 to the -11th/yr is consistent with both historical observations of the nontidal acceleration of the earth's rotation and models of viscous rebound of the solid earth from the decrease in load due to the last deglaciation.
Interstitial water sampling by dialysis: Methodological notes

The dialysis technique for sampling interstitial waters is subject to several potential sources of error. Cellulose-based membranes can lead to the underestimation or overestimation of porewater solutes. Polycarbonate was found unsuitable for dialyzer construction because of iron precipitation problems. The initial presence of dissolved O2 in the compartments can significantly affect sample composition. Equilibration times of 15–20 days were found adequate for most sediments. An efficient technique for pH measurement in small volumes of porewater is described.
Nonlinear Analysis of Two-Phase Flow in Polymer Electrolyte Fuel Cell Cathode Microchannels

In this work, we apply a nonlinear chaos analysis to the two phase flow in polymer electrolyte fuel cell cathode air-delivery microchannels. The fuel cell voltage signal is analyzed using techniques designed to estimate invariants typical of deterministic systems with high sensitivity to initial conditions, such as chaotic two phase flow. Voltage data are taken under varying fuel cell operating conditions, and noise in the data is reduced using a nonlinear noise reduction algorithm. The chaotic strange attractor of the system is reconstructed in phase space using time-delay embedding. Correlation sums over the strange attractor are calculated to estimate the fractal correlation dimension of the system. Estimations of the Kolmogorov entropy provide an additional measure of the complexity of the strange attractor. The values of the chaotic invariants are compared across varying degrees of cathode flooding to discern how they change with two phase flow regimes and fuel cell operating conditions. Future work will involve leveraging the chaotic understanding of two phase flow with chaos control methods to increase the power stability.Copyright © 2012 by ASME
Perspectives in anatomy and pathology of paraplegia in experimental animals

Abstract Three models of inducing spinal trauma in experimental animals—weight-dropping model, severance-by-knife model, and laceration-type-lesions model—are reviewed critically. Contributions by these models in understanding paraplegia in anatomical and pathological terms are brought out. Important distinctions between subthreshold traumas vs. threshold and suprathreshold traumas, transient and permanent paraplegic syndrome, and regeneration of severed axonal fibers vs. prevention of development of permanent paraplegia, are stressed while evaluating each model of spinal trauma. Conceptual contributions by these three models and their bearing on the potential clinical applications are discussed.
The effect of cross-scatter correction on the performance of dual energy micro-CT

Dual energy (DE) CT imaging is expected to play a major role in the diagnostic arena as it provides a quantitative decomposition of basis materials, opening the door for new clinical applications without significantly increasing dose to the patient. DE-CT provides a particularly unique opportunity in preclinical CT where new elemental contrast agents are providing novel approaches for quantitative tissue characterization. We have implemented DE-CT imaging with a preclinical dual source micro-CT scanner. With this configuration, both forward and cross-scatter can substantially degrade image quality. This work investigated the effect of scatter correction on the accuracy of post-reconstruction iodine and calcium decomposition. Scatter has been estimated using a lead beam stop technique. Our approach involves noise reduction in the scatter corrected images using bilateral filtering. The scatter correction has been quantitatively evaluated using phantom experiments and in vivo cancer imaging. As shown by our measurements, the dual source scanning is affected more by the cross-scatter from the high energy to the low energy imaging chain. The scatter correction reduced the presence of cupping artifacts and increased both the accuracy and precision of dual energy decompositions of calcium and iodine. On average, the root mean square errors in retrieving true iodine and calcium concentrations via dual energy were reduced by 32%. As a result of scatter corrections, we expect more accurate quantification of important vascular biomarkers such as fractional blood volume and vascular permeability in preclinical cancer studies.
Neural network solution for finite-horizon H ∞ constrained optimal control of nonlinear systems

In this paper, neural networks are used to approximately solve the finite-horizon constrained input H∞ state feedback control problem. The method is based on solving a related Hamilton-Jacobi-Isaacs equation of the corresponding finite-horizon zero-sum game by approximating the cost using a Neural Network. It is shown that the neural network approximation converges uniformly to the game-value function and the resulting nearly optimal constrained feedback controller provides closed-loop stability and bounded L2/ gain. The result is a nearly optimal H∞ feedback controller with time-varying coefficients that is solved a priori offline. The effectiveness of the method is shown on the rotational/translational actuator benchmark nonlinear control problem.
A quantitative analysis of the incorporation of fibulin-1 into extracellular matrix indicates that fibronectin assembly is required

Abstract Fibulin-1 is an extracellular matrix glycoprotein found in both loose and dense connective tissues, elastic fibers and some basement membranes. Cultured cells such as fibroblasts assemble endogenously synthesized or exogenously added fibulin-1 into matrix fibrils that also contain fibronectin. Since we have previously shown that fibulin-1 binds to fibronectin (Balbona, K., Tran, H., Godyna, S., Ingham, K.C., Strickland, D.K. and Argraves, W.S. J. Biol. Chem. 267: 20120–20125, 1992), we sought to investigate fibulin-1 incorporation into fibroblasts extracellular matrix with an emphasis on evaluating the potential role of fibronectin in the process. In this study, we have used quantitative assays to measure the binding of 125 I-fibulin to monolayers of cultured fibroblasts. Our results show that the kinetics of fibulin-1 incorporation into the cell layer and its partitioning into detergent-soluble and -insoluble fractions were similar to those of fibronectin. It was found that antibodies to fibronectin or to the fibulin-1-binding domain of fibronectin-inhibited fibulin-1 incorporation. Cell lines that fail to assemble fibronectin into the matrix, such as HT1080 or PEHR-9, do not incorporate fibulin-1 into their cell layers. However, when HT1080 cells were induced to assemble fibronectin by treatment with dexamethasone, they subsequently acquired the ability to incorporate fibulin-1. Moreover, treatment of cultured fibroblasts with antibodies that inhibit fibronectin assembly significantly inhibit fibulin-1 incorporation into the matrix. When increased amounts of fibronectin were incorporated into cells layers by incubating the cells for varying lengths of time with exogenous fibronectin, a corresponding increase in fibulin-1 incorporation was also observed. Taken together, the data indicate that the incorporation of fibulin-1 requires fibronectin assembly and suggests a dependence on the amount of fibronectin in a matrix. These results highlight the potential of fibronectin to control the deposition of fibulin-1 into those extracellular matrices where both proteins coincide and may have implications in the formation of fibulin-1-containing matrix structures such as basement membranes or elastic fibers.
Chronic food restriction and weight loss produce opioid facilitation of perifornical hypothalamic self-stimulation.

Electrical stimulation frequency thresholds for lateral hypothalamic (LH) self-stimulation were monitored throughout a 3 week period of food restriction and a subsequent 3 week period of re-feeding. Rats with electrodes placed in the perifornical LH were sensitive to this dietary manipulation as evidenced by a high positive correlation between body weight and self-stimulation threshold. Rats with electrodes in the zona incerta/subincertal region or ventral hypothalamus displayed little or no change in threshold. Lateral ventricular injection of naltrexone (200.0 nM) reversed the decline in threshold that was otherwise present during food restriction in rats with perifornical placements. Naltrexone had no effect on thresholds of rats with placements outside the perifornical region. These findings suggest that food restriction and weight loss activate an opioid mechanism that facilitates perifornical LH self-stimulation. The documented association of perifornical LH with the phenomenon of stimulation-induced feeding, and the reciprocal connections between this region and gustatory structures, supports the hypothesis that facilitation of self-stimulation by food restriction is related to the natural phenomenon of positive alliesthesia (i.e. the hunger-dependency of food reward).
Effect of vagotomy upon intragastric redistribution of microvascular flow

Vagotomy is an effective form of therapy for bleeding from acute gastric mucosal erosions (stress ulcers). The mechanism of its effect is not fully understood, but alterations in microvascular blood flow within the stomach have been postulated. Since stress ulcers occur almost exclusively in the body of the stomach, experiments were performed to compare the effects of vagotomy upon the microcirculation of the oxyntic gland (corpus) and pyloric gland (antrum) regions of the rat stomach. The experiments employed direct in vivo observations in chloraloseanesthetized Wistar rats using a video microscope system that allowed magnifications of up to 300x. Changes in microvessel diameter and rate of flow were analyzed during playback of videotapes. Following bilateral truncal vagotomy there was increased flow in the pyloric submucosal microvessels but no change in mucosal flow for up to 1 hr. In the oxyntic gland area there was decreased submucosal flow and venous congestion in the mucosal layer. No arteriovenous anastomoses were seen either before or after vagotomy. This intragastric redistribution of microvascular blood flow may be important factor in the beneficial effects that vagotomy has in bleeding stress ulcers.
The Stable Isotope Ratios of Marijuana. II. Strontium Isotopes Relate to Geographic Origin

Effectively addressing marijuana trade is aided by understanding marijuana geographic sources. We analyzed the87Sr ⁄86Sr of mar-ijuana samples grown in 79 counties across the United States to determine if a primary geologic signal is retained in marijuana, which could thereforebe useful for geographic sourcing. The marijuana results were compared with modeled bedrock87Sr ⁄86Sr values based on87Rb decay rates and ageneralized geologic map of the U.S.A. A significant correlation was observed between marijuana87Sr ⁄86Sr and modeled bedrock87Sr ⁄86Sr.Although values clustered near the 1:1 relationship, there was a predominance of positive anomalies, perhaps attributable to carbonate bedrock. Asmall number of negative anomalies were also observed, which were generally associated with granitic bedrocks. These results suggest that strontiumisotopes in marijuana record the geographic origins of marijuana, and that refinement of the base strontium map (or strontium isoscape) and improvedunderstanding of other strontium sources would be productive
Uniformly Approximable Numbers and the Uniform Approximation Spectrum

Abstract We say a real number α is uniformly approximable if the upper bound in Dirichlet's theorem, from diophantine approximation, of 1/( Q +1) q may be sharpened to c ( α )/( Q +1) 2 for all sufficiently large Q . Here we begin by showing that the set of uniformly approximable numbers is precisely the set of badly approximable numbers. In additition, the optimal lower bound of c ( α ), referred to as the uniform approximation constant, is explicitly given. This allows us to introduce the notion of a uniform approximation spectrum. We conclude with a determination of the smallest values of this new spectrum and a comparison of this spectrum with other spectra.
N III line emission in planetary nebulae - Not Bowen fluorescence

A direct comparison of photometrically observed line ratios in the N III 4640 and 4100 A multiplets emitted by planetary nebulae with theoretically predicted ratios expected from the postulated Bowen process of selective photoexcitation by an O III resonance line shows that the N III lines are not produced by the Bowen process as has been commonly accepted. This will have consequences for the interpretation of these lines in other astrophysical sources. A further, unexpected result is that the N III level populations involved are found to be essentially in statistical equilibrium. Possible populating mechanisms are briefly discussed.
Cofunction in composite systems

Abstract Binary relations among states of system components are examined bearing information about their cooperation (cofunction) and its possible breakdown. Illustrative examples from biology and applications dealing with sequential machines, acceptable state transitions and tolerance relations are given.
Acidities in Cyclohexanediols Enhanced by Intramolecular Hydrogen Bonds

Equilibrium gas-phase acidities of the six isomeric cyclohexanediols were measured in a Fourier transform ion cyclotron resonance mass spectrometer. Although all six cyclohexanediols have the same functional groups and similar structures, the acidities vary over 11 kcal/mol. This large difference is due mostly to the balance between hydrogen bonding and geometric strain. To understand the origins of the acidity differences in more detail, the conformations and energetics of the cyclohexanediols were studied using density functional theory, which gave good agreement with the experimental acidities. Finally, methanol-methoxide and methanol-methanol interactions were used as a model for the hydrogen bonding.
Backbone assignments of mini-RecA intein with short native exteins and an active N-terminal catalytic cysteine

The backbone resonance assignments of an engineered splicing-inactive mini-RecA intein based on triple resonance experiments with [(13)C,(15)N]-labeled protein are reported. The construct contains inactivating mutations specifically designed to retain most catalytic residues, especially those that are potentially metal-coordinating. The assignments are essential for protein structure determination of a precursor with an active N-terminal catalytic cysteine and for investigation of the atomic details of splicing.
Development of a PCR Assay for the Rapid Detection and Differentiation of ‘Candidatus Liberibacter solanacearum’ Haplotypes and Their Spatiotemporal Distribution in the United States

Zebra chip, or zebra complex (ZC) has become an important invasive disease of potato in the United States and New Zealand and is caused by a phloem-limited bacterium, ‘Candidatus Liberibacter solanacearum’ (Lso). A PCR assay using a single pair of simple sequence repeat (SSR) primers was developed for simultaneous detection and genotype differentiation of Lso haplotypes associated with zebra chip disease of potato. The sensitivity of the SSR PCR was similar to a 16S PCR assay, with detection limit of 100 copies of the Lso genome in haplotype A infected potato and psyllid samples and 10 copies of Lso genome in haplotype B potato and psyllid samples. The Lso detection frequency of the SSR PCR assay was 79.1 % in potato and 26.4 % in psyllid samples, respectively; whereas the detection frequency of the 16S PCR assay 59.0 % in potato and 25.9 % in psyllid samples, respectively. Samples of Lso positive potato plants and psyllids from multiple states in the US were demonstrated to have either haplotype A or haplotype B Lso and occasionally both haplotypes were found in individual samples. This is the first report that co-infection of the two haplotypes of Lso exists in potato and potato-psyllid samples. Only haplotype A Lso was detected in North Dakota psyllid samples collected in 2010, in Idaho and Washington ZC potato samples sampled from storage in 2011, and in Idaho ZC potato samples in 2012. Haplotype A Lso was also detected in New Zealand ZC affected potato samples and psyllid samples collected in 2010 and 2011. The PCR assay developed is as sensitive as previously developed assays and has the advantage of simultaneously detecting and differentiating Lso haplotypes of the ZC bacterium, thus making it extremely useful for epidemiological studies.
Breaking the Rules When Others Do

People often speak as if the behaviour of others is relevant to the question of whether they are justified in violating a rule. This paper explores three lines of argument which might be used to justify rule violation on grounds appealing to what others do. The appeal to self-defence as a justification does not succeed, since it must expand the concept to involve a cumbersome weighing of harms. The argument that complying with a rule may involve too great a sacrifice in some cases needs to be developed by an account of when a sacrifice is morally significant. It is tempting, but problematic, to do this by weighing consequences of individual acts. An alternative approach is to argue that the behaviour of others is sometimes relevant to determining what rule is actually functioning in some context as a part of a particular moral system.
Effect of the Systemic Inflammatory Response on Biochemical Markers of Neonatal Bacterial Infection: A Fresh Look at Old Confounders

“Rule out sepsis” remains a persistently frustrating diagnosis in neonatology. It a common diagnosis: in the US, where 400 000 to 600 000 newborns are evaluated with a complete blood count (CBC) and blood culture each year, it is probably the second most common neonatal diagnosis after “well baby” (1)(2)(3). No one disputes that babies with clear-cut clinical signs of infection should receive systemic antibiotic therapy. However, beyond these two facts, and despite individual nursery protocols somehow keeping the problem—more or less—under control, multiple disagreements exist. Discord is most pronounced in two areas. The first is what test or combinations of tests permit one to diagnose sepsis early enough and reliably enough. After all, by the time a newborn shows clear-cut signs of infection, it is usually pretty late in the game (1). The second concerns newborns with maternal risk factors who are initially asymptomatic: what constitute appropriate criteria for initiating antibiotic therapy in such infants (4)(5)(6)? Faced with these questions, many investigators have attempted to find the diagnostic equivalent of a “magic bullet”, and a voluminous literature now exists advocating individual diagnostic tests or combinations of diagnostic tests, as well as combinations of a diagnostic test or tests with risk factors and/or clinical signs. All of these studies have yielded conflicting results, and the fact that these studies keep appearing in our journals highlights the fact that satisfactory solutions remain to be found. In this issue, Chiesa et …
Development of Woronin bodies from microbodies in Fusarium oxysporum f.sp. lycopersici.

Woronin bodies are cytoplasmic organelles which commonly lie near the septa in ascomycetous fungi. Although these organelles were observed nearly 100 years ago, little is known about their origin and development. The present ultrastructural investigation describes the ontogeny of Woronin bodies inFusarium oxysporum f. sp.lycopersici [Sacc.] Snyd. and Hans. In this fungus, Woronin bodies are produced by microbodies. Development of the Woronin body begins with the appearance of electron dense material within the microbody. This material aggregates adjacent to the membrane of the microbody and condenses into a single paracrystalline inclusion. Following its formation, the inclusion is gradually extruded and is eventually separated from the parent organelle by an exocytotic mechanism. After the separation, the paracrystalline inclusion is found at the septal pore. Although many recent electron microscopic studies have used various terms to designate these membrane bound organelles, inFusarium these inclusions are believed to correspond to the Woronin bodies initially described by light microscopists.
Ethnic Variation in Whether Dissociation Mediates the Relation Between Traumatic Life Events and Attenuated Positive Psychotic Symptoms

The present study sought to determine whether dissociative experiences mediated the relationship between traumatic life events and attenuated positive psychotic symptoms in a non-treatment-seeking sample of racial and ethnic minority young adults. Participants (n = 549) completed a self-report inventory for psychosis risk (i.e., the Prodromal Questionnaire; R. L. Loewy, C. E. Bearden, J. K. Johnson, A. Raine, & T. D. Cannon, 2005), from which a total number of attenuated positive psychotic symptoms was assessed. Participants also completed a checklist of potentially traumatic life events and a traumatic dissociation scale. Hierarchical linear regression models and bootstrapping results indicated that dissociation mediated the relationship between traumatic life events and attenuated positive psychotic symptoms. Stratified analyses of Black, Asian, and Hispanic subgroups revealed that full mediation was only evident in the Black subgroup of young adults. Partial mediation was found among the Hispanic group, and no mediation occurred in the Asian subgroup. For the latter, traumatic life events were not significantly associated with dissociative experiences. A dissociative response style may be particularly relevant to trauma-exposed Black young adults exhibiting subclinical psychotic experiences and less so for Asian young adults. Trauma-induced dissociative experiences should be assessed further in clinical high-risk studies, especially among Black traumatized youth.