cssi/SciSciGPT-SciSciNet huggingface dataset:
Identification of novel components of NAD-utilizing metabolic pathways and prediction of their biochemical functions

Nicotinamide adenine dinucleotide (NAD) is a ubiquitous cofactor participating in numerous redox reactions. It is also a substrate for regulatory modifications of proteins and nucleic acids via the addition of ADP-ribose moieties or removal of acyl groups by transfer to ADP-ribose. In this study, we use in-depth sequence, structure and genomic context analysis to uncover new enzymes and substrate-binding proteins in NAD-utilizing metabolic and macromolecular modification systems. We predict that Escherichia coli YbiA and related families of domains from diverse bacteria, eukaryotes, large DNA viruses and single strand RNA viruses are previously unrecognized components of NAD-utilizing pathways that probably operate on ADP-ribose derivatives. Using contextual analysis we show that some of these proteins potentially act in RNA repair, where NAD is used to remove 2'-3' cyclic phosphodiester linkages. Likewise, we predict that another family of YbiA-related enzymes is likely to comprise a novel NAD-dependent ADP-ribosylation system for proteins, in conjunction with a previously unrecognized ADP-ribosyltransferase. A similar ADP-ribosyltransferase is also coupled with MACRO or ADP-ribosylglycohydrolase domain proteins in other related systems, suggesting that all these novel systems are likely to comprise pairs of ADP-ribosylation and ribosylglycohydrolase enzymes analogous to the DraG-DraT system, and a novel group of bacterial polymorphic toxins. We present evidence that some of these coupled ADP-ribosyltransferases/ribosylglycohydrolases are likely to regulate certain restriction modification enzymes in bacteria. The ADP-ribosyltransferases found in these, the bacterial polymorphic toxin and host-directed toxin systems of bacteria such as Waddlia also throw light on the evolution of this fold and the origin of eukaryotic polyADP-ribosyltransferases and NEURL4-like ARTs, which might be involved in centrosomal assembly. We also infer a novel biosynthetic pathway that might be involved in the synthesis of a nicotinate-derived compound in conjunction with an asparagine synthetase and AMPylating peptide ligase. We use the data derived from this analysis to understand the origin and early evolutionary trajectories of key NAD-utilizing enzymes and present targets for future biochemical investigations.
Three-point boundary value problems for ordinary differential equations by matching solutions☆

Motivational results for solution matching were proven first in the text by Bailey et al. [l] where they dealt with solutions of two-point problems for y” = f(x, y, y’) by matching solutions of initial value problems. Then in 1973, Barr & Sherman [2] adapted the arguments of Bailey et al. to match solutions of two-point boundary value problems for third order equations to obtain solutions of three-point problems. In the same paper, they showed that this result could be generalized to equations of arbitrary order yielding solutions of (l), (2). Barr & Miletta [3] matched solutions of k-point problems for nth order linear equations and obtained solutions of n-point conjugate type boundary value problems. In 1978, Moorti & Garner [4] extended the results of [2] to boundary value problems similar to (l), (3), except p, Y were restricted
Quasi-Quantum Computing in the Brain?

Quantum computing has been seen as a potentially powerful computing method, and consequently some researchers have argued that the brain might somehow utilize quantum computing processes. In the laboratory, quantum computing calls for exotic conditions, and it has been argued that the brain cannot provide these. Here, a novel computing method, quasi-quantum computing, is presented. This method utilizes the main principles of quantum computing: superposition, entanglement and collapse, but in this case, computing is not based on quantum processes; instead, it is realized by utilizing conventional electronic devices in rather unconventional ways. As an example of the potential of this approach, the reverse computing of mathematical functions is considered, and an experimental test device is reported. Some aspects of this approach may be used by the brain as no exotic conditions are required. However, further research would be required.
Effects of pH on erythrocyte metabolism

Abstract Anion-exchange analysis of nucleotides and other phosphate esters has been used to study the effects of pH on the levels of these organic phosphates during in vitro incubation of human erythrocytes for 5 hours. The pH of incubated samples was raised by ( a ) permitting carbon dioxide to diffuse out of the sample and ( b ), by addition of isotonic, pH 8.6 Tris buffer. In either case, the consequences of incubation at a pH of 7.6–7.7 were as follows: ( a ) an increase in the AMP:ATP and ADP:ATP ratios; ( b ) an increase in the level of hexose diphosphate; ( c ) a decrease in the level of inorganic phosphate; and ( d ) a marked increase in the rate of breakdown of adenine nucleotides to hypoxanthine. The probable causes for these changes are discussed.
Image-based estimation of ventricular fiber orientations for patient-specific simulations

Patient-specific simulation of heart (dys)function aimed at personalizing cardiac therapy are hampered by the absence of in vivo imaging technology for clinically acquiring myocardial fiber orientations. In this research, we develop a methodology to predict ventricular fiber orientations of a patient heart, given the geometry of the heart and an atlas. We test the methodology by comparing the estimated fiber orientations with measured ones, and by quantifying the effect of the estimation error on outcomes of electrophysiological simulations, in normal and failing canine hearts. The new insights obtained from the project will pave the way for the development of patient-specific models of the heart that can aid physicians in personalized diagnosis and decisions regarding electrophysiological interventions.
Species difference in the binding of aflatoxin B1 to hepatic macromolecules

Abstract The binding of [ 14 C]aflatoxin B 1 to the RNA, DNA, and protein of liver after ip administration to adult rats, mice, and guinea pigs and of the in vitro binding to the plasma protein of these species was studied. Binding to nucleic acids was greater than to liver protein in all three species. Binding to hepatic macromolecules and plasma of mice was considerably less than that of the other two animal species. The specific radioactivity of guinea pig liver RNA and protein was higher than the corresponding fractions in rat liver, which correlates with the higher reported acute sensitivity of guinea pigs than rats to aflatoxin B 1 . Guinea pig liver DNA, however, contained somewhat less radioactivity than did rat liver DNA, which may be related to the resistance of the guinea pig to the hepatocarcinogenicity of aflatoxin B 1 .
Fine structure and function of planarian goblet cells

Planarians secrete quantities of mucus that appears to contain one or more glycoproteins as its major constituent. The fine structure associated with the various maturational and functional stages of a type of secretory cell of the planarian Dugesia dorotocephala is described which appears to be isomorphic with the goblet cells involved in the mucous secretion of mammals. This type of secretory cell, which occurs in large numbers in D. dorotocephala , differs from other cells which have been implicated in planarian mucous secretion. It originates and matures in the mesenchymal regions of the planarian, then migrates through the ectodermal basement membrane into the ducts penetrating the ectodermal cell layer. In its early stages it has a pronounced laminar endoplasmic reticulum and extensive Golgi complex activity. Electron transparent vesicles bud off from the tubes of the Golgi complex. These vesicles then, by swelling or coalescing, form the large mucus-filled Golgi vacuoles which almost completely fill the cytoplasm of the mature cell.
Information effects of First Republic Bank's failure

An overriding concern in the US financial system is an event or rumour that reduces public confidence in banks. The existence of regulatory agencies in the banking system is largely motivated by th...
Rate of relapse following treatment for localized prostate cancer: A critical analysis of retrospective reports

Abstract Purpose : Controversy exists over the optimal treatment for patients with clinically localized prostate cancer. Almost all of the treatment results are from non-randomized trials and interseries comparison is difficult since the apparent success of a treatment, as judged by the actuarial freedom from relapse and survival data, depends on patient selection criteria and post-treatment evaluation, in addition to the efficacy of the therapeutic intervention. In this report the calculation of a hazard function is used to estimate and compare the rate of relapse for the different treatments. Methods and Materials : Clinical reports from major surgery and radiation oncology treatment institutions were analyzed. The actuarial recurrence data were used to calculate the annual rate of recurrence within each series. Results : For all but the lowest volume tumors, patients continueto be at rist of relapse for as long as these series have been followed. Despite the heterogeneity of patient populations, the recurrence rates by stage are similar for patients treated with surgery or irradiation. This result is consistent with pathologic data from prostatectomy specimens which indicate that for lesions > 12 cm3 (approx. 3 cm in diameter) there is high likelihood of extraprostatic disease. Conclusion : Treatment outcome for patients with localized prostate cancer may be more dependent on the inherent tumor biology than the particular type of treatment. Accordingly, the expectation and recommendation of a treatment must take into consideration the continued risk of relapse with either radiation therapy or surgery. There are, as yet, insufficient data regarding the impact of screening and earlier diagnosis on the curability of patients with localized prostate cancer.
Spontaneous roughening: fundamental limits in Si(100) halogen etch processing.

A dynamical scanning tunneling microscopy and density functional theory study of the thermodynamic stability of halogen-terminated Si(100) surfaces is presented. Significant steric repulsions are shown to exist on all halogen-terminated Si(100) surfaces. These repulsions are the driving force for a roughening phenomenon, which is favored for all halogens except fluorine. Since roughening is an intrinsic property of these surfaces, it sets a lower bound on the atomic scale perfection that can be achieved using halogen etch processing.
THE HISTOPATHOLOGY AND PREVALENCE OF Henneguya sebasta AND Kudoa clupeidae IN THE ROCKFISH, Sebastes paucispinis OF SOUTHERN CALIFORNIA

The pathogenesis of two histozoic myxosporidans, Henneguya sebasta and Kudoa clupeidae, was studied from the Pacific rockfish, Sebastes paucispinis. Infection of the bulbus and truncus arteriosus with H. sebasta was observed in 30 of 100 fish. The parasite metastasized throughout the tissue causing necrosis, hyperplasia and hypertrophy of the connective tissue and smooth muscle. K. clupeidae, found in 37 of 100 fish, caused necrosis and atrophy of host skeletal muscle. The unattractive appearance of Kudoa cysts in rockfish filets detracted from their commercial value.
Hippocampal electrical activity III. Unitary events and genesis of slow waves

Abstract Evidence has been brought forward to suggest that the slow wave activity of the rabbit hippocampus is dependent on the summed activity of slow potentials (“inactivation” processes) which in turn seem to be generated by summed postsynaptic potentials. Probably the limited extraneuronal space, described in paper I, plays a role in these events and in the marked hysteresis noted in amplitude of hippocampal pyramidal spikes when plotted against interval. This effect is not limited from one spike to the immediately succeeding one.
Mutant membrane protein toxicity.

This report describes an extensive mutational analysis of the most carboxyl-terminal membrane-spanning sequence of Escherichia coli lac permease (TM12). In addition to identifying residues important for lactose transport function, the analysis revealed that numerous mutations made lac permease highly toxic to cells. In the most extreme cases, production of such proteins at very low steady-state levels reduced cell viability greater than 104-fold. Both frameshift and missense mutations led to toxicity, with the frameshift mutations having the strongest effects observed. The toxic missense mutations corresponded to changes in TM12 expected to interfere with membrane insertion or folding, such as the introduction of charged residues or prolines in the putative helix. The results suggest that cellular toxicity may be a relatively common consequence of mutations altering integral membrane protein folding. An analogous toxicity might contribute to the pathogenesis of several degenerative diseases caused by mutant membrane proteins, such as retinitis pigmentosa, Charcot-Marie-Tooth syndrome, and Alzheimer's disease.
The Debate: A Strategic Technique

This paper describes the work of a strategic team that came out from behind the one-way mirror. A debate among the team is enacted before the family as a strategy for change. The case of a family that refused to provide information illustrates an application of this method. The debate among the therapists represents a dilemma that is a strategically constructed isomorph of the family situation. From this position, therapists have the option of changing levels between themselves and the family, asking the family to help solve the therapists' dilemma so that they in turn can be free to help the family. The combination of the debate and the change of levels between the therapists and the family creates a therapeutic neutrality for the family. From their meta position, they observe the therapists' struggle to solve the family's problem, which is re-presented as a problem among the therapists. This perspective offers the family the choice of more adaptive solutions to their own dilemma.
Infrared measurement of the optical constants of the low melting temperature glass system of 30% arsenic — 34% sulfur — 36% thallium

Abstract The low melting temperature, heavy metal sulfide glass system of arsenic, sulfur, and thallium has proven to be optically clear from 1 to 23 μ in wavelength. The optical constants, consisting of absorption coefficient, reflection coefficient, extinction coefficient, and refractive index, have been determined from 2 to 23 μ in wavelength. The reflection coefficient was calculated from a plot of transmission measurements as a function of sample thickness, extrapolated to zero thickness. In turn, this data, through the application of the Kramers-Kronig relationship, has yielded both the real and imaginary portions of the refractive index. As a result of the low working temperature of this composition glass, the possibility exists of manufacturing lenses and domes by molding between Teflon dies and other materials.
Synthesis and evaluation of fluorinated calcium chelators with enhanced relaxation characteristics

The fluorinated calcium ion chelator 5F BAPTA [1,2-bis(2-amino-5-fluorophenoxy)ethane-N, N, N′, N′-tetra-acctic acid] was used for the determination of cytosolic Ca2+ ion levels in cells and tissues by 19F NMR. The possibility of enhancing the sensitivity of these measurements by modifying the relaxation behavior of the chelator was evaluated. These strategies involved the design of a chelator with reduced T1 value viz. 5F RBAPTA {1,2-bis [2-amino-4-(1-carboxy-2-methyl-2-propyl)-5-fluorophenoxy]ethane-N, T, N′, N-tetraacetic acid}, and the evaluation of chelator with slower exchange characteristics, viz 5F BenzEGTA [1-(2-amino-5-fluorophenoxy)-2-(2-aminoethoxy)ethane-N, N, N′, N′-tetraacetic acid]. Both analogs exhibit chemical shift differences on calcium complexation which are similar to those of the parent compound, 5F BAPTA. In the case of BenzEGTA, a considerably greater pH dependence of the apparent calcium, dissociation constant, KD, also results from the presence of a tertiary amine with a pK value above the physioligical range. Additionally, the synthetic approach used for RBAPTA can lead to wide variety of derivatives with variable chemical, biochemical and NMR properties.
Calcium Binding Proteins (CaBPs) Selectively Modulate Cav1 versus Cav2 Channels

Calcium-binding proteins (CaBPs) comprise a subfamily of calmodulin (CaM)-like neuronal Ca2+-binding proteins that are widely expressed throughout the brain. Intriguingly, CaBPs have been reported to blunt the CaM-mediated Ca2+ feedback regulation in multiple subtypes of CaV1, and even CaV2 channels (Nat Neurosci 5:210). This modulation of Ca2+ feedback potentially influences numerous neurobiological functions, thus motivating ongoing investigation of the mechanism of CaBP effects. Here, in the course of discerning the structural determinants of CaBP operation, we uncovered striking selectivity in the actions of CaBPs for CaV1, but not CaV2 channels. While mouse mCaBP4 eliminates Ca2+/CaM-mediated inactivation (CDI) of CaV1 channels (confirming reports of multiple groups), we now find no such effect on both Ca2+/CaM-dependent facilitation (CDF) of CaV2.1 channels and CDI of CaV2.1 and CaV2.3 channels. Indeed, further analysis revealed the structural basis for such selectivity. Systematic FRET 2-hybrid assays revealed a bevy of CaBP4 binding sites on various intracellular regions of CaV1.3. As such, we made chimeric channels using CaV2.3 as the backbone, and substituting intracellular loops from CaV1.3 to identify functionally relevant mCaBP4 sites. Transfer of the CaV1.3 carboxyl terminus was sufficient to confer mCaBP4 modulation on CaV2.3 channels, but CDI was only partially blunted by mCaBP4. By contrast, substitution of the amino-terminus, III-IV loop, and carboxyl-terminus of CaV1.3 into CaV2.3 resulted in complete elimination of CDI by mCaBP4. These results suggest that mCaBP4 acts in concert through multiple sites to fully eliminate CDI. Because mouse mCaBP4 induces the most potent effects, we emphasized characterization with this particular CaBP, though other CaBPs may reproduce the same trends. The remarkable ability of CaBPs to selectively modulate only CaV1 but not CaV2 channels opens new avenues for customization of neurobiological effects, and for development of selective pharmacology targeting Ca2+ regulation.
Decoupling approximations for structural acoustic interactions

Abstract The model problem of acoustic scattering by a baffled membrane is formally cast as a dual integral equation. A class of approximations are made to the equation's kernel and each gives rise to an analytically solvable problem. Each of these approximate problems corresponds to an existing physical theory which was derived in a complete by different manner. The present method of analysis systematically deduces these theories, suggests potentially useful new ones, and indicates where more theoretical studies are required.
Chytrid infection reduces thoracic beat and heart rate of Daphnia pulicaria

Zooplankters are hosts to numerous endo- and ectoparasites, some of which have dramatic impacts on their hosts. Epizootics on zooplankton are probably more widespread in lake systems than it is currently known, and few studies have explored the direct and indirect importance of parasitism in aquatic food webs. In addition, our understanding of the sublethal effects of parasitic infections on host organisms and populations is limited. We used a novel electro-chemical based technique to measure in the outflow of the feeding current changes in the beat rate of the thoracic appendages in female Daphnia pulicaria. We observed simultaneously the heart rates and compared chytrid infected animals with uninfected gravid and non-gravid ones. We found in uninfected animals a thoracic beat rate of 3.81 ± 018 Hz and a heart rate of 4.67 ± 0.42 Hz. Gravid daphnids had a 14% lower thoracic beat rate (3.27 ± 0.30 Hz) than non-gravid females while the heart rate did not significantly differ (4.48 ± 0.28 Hz). In contrast, infected animals showed a 22% lower thoracic beat rate (2.96 ± 0.47 Hz) and a 36% lower heart rate (2.98 ± 0.5 Hz) when compared with uninfected non-gravid females. We discuss the ways Daphnia are affected by Polycaryum leave infections on the individual and population level.
Fat Embolism Syndrome

A 49-year-old man with a history of prostate cancer metastatic to bone suffered a pathological fracture to the left femur while hospitalized (Figure 1A). Eighteen hours after the fracture, he developed hypoxemia and hypotension followed by confusion and a petechial rash in the left axilla. Chest X-ray obtained after intubation demonstrated new diffuse bilateral patchy infiltrates (Figure 1B). Urgent transthoracic echocardiogram showed right ventricular dilation and free wall hypokinesis with preserved contractility of the right ventricular apex (McConnell’s Sign; Figure 2, Movie I in the online-only Data Supplement). Based on the clinical presentation and supportive imaging, the patient was diagnosed with fat embolism syndrome. He was transferred to the intensive care unit for further management. Figure 1. Initial imaging. X-ray of the left lower extremity demonstrating a closed, oblique fracture of the left femur with displacement of the distal femoral fragment ( A ). Chest X-ray obtained shortly after endotracheal intubation showing bilateral patchy infiltrates consistent with acute respiratory distress syndrome (ARDS; B ). Figure 2. Transthoracic echocardiogram images obtained during diastole ( A ) and systole ( B ) demonstrating right ventricular dysfunction with hypokinesis of the mid right ventricular free wall and preservation of the apex. Although it was observed centuries ago that intravenous injection of oil resulted in mechanical obstruction of small vessels,1 the exact pathophysiology of fat embolism syndrome (FES) remains uncertain. Fat embolism (FE) is defined by the presence of fat globules in the pulmonary microcirculation regardless of clinical significance. FES describes a characteristic pattern of clinical findings that follow an insult associated with the release of fat into the circulation. FES is most commonly associated with orthopedic trauma, with highest incidence in closed, long bone fractures of the lower extremities, particularly the femur.2 The risk of FES complicating orthopedic trauma is highest in ages 10 to 40 years and occurs in …
Calorimetric measurement of stepwise enthalpy changes for the binding of four oxygens to adult human hemoglobin.

Abstract The successive enthalpy changes for the four steps of oxygen binding by diphosphoglycerate-free adult human hemoglobin have been measured by direct calorimetry at pH 7.4 and 6°. Average results in kcal/(mole O2) are: ΔH1 = −25.1 ± 2.8; ΔH2 = −12.6 ± 3.0, ΔH3 = −12.5 ± 3.0, and ΔH4 = −10.1 ± 1.4. These results imply a substantial temperature dependence for the cooperativity of O2 binding by the protein and generally resemble the van't Hoff results by Roughton et al . [Roy. Soc. of London Proc., B 144 , 29 (1955)] for sheep hemoglobin at pH 9.1 and a temperature range of 2° to 19°.
Music Abilities and Experiences as Predictors of Error-Detection Skill

This study examined the predictive validity of previous music abilities and experiences of skill in music error detection among undergraduate instrumental music education majors. The predictor variables included number of instruments played; ensemble experience; ability in music theory, sightsinging and ear training, and years of precollege private instrumental instruction. Results indicated no statistically significant relationship between each of the predictor variables and skill in music error detection. This suggests that the ability to detect music errors may exist independently of other music abilities. The benefits accrued through participation in one kind of music activity may not contribute to other areas of music development.
On the Existence, Uniqueness and Correctness of the Fracture Diameter Distribution Given the Fracture Trace Length Distribution

Based on the fracture trace length distribution, conditions for the existence, uniqueness, and correctness of the fracture diameter distribution are given using Warburton’s fracture model. In particular, a solution for the fracture diameter distribution exists and is unique for all trace length probability density functions, h A (y), such that $h_{A}(y)/\sqrt{y^{2}-x^{2}}$ is Lebesgue integrable on [x,∞). This condition is met by the uniform, exponential, gamma, lognormal, and power-law trace length distributions as well as by the trace length distributions that arise from a deterministic fracture diameter or from a discontinuous fracture diameter length distribution. Exponential, gamma, lognormal, and power-law trace length distributions satisfy necessary conditions for the diameter distribution to be non-negative, and necessary and sufficient conditions for the distribution to have unit integral over the real line. Negative values of the fracture diameter distribution arise when the trace has a uniform distribution and the lower bound of the fracture trace is greater than zero.
Vascular complications following coronary intervention correlate with long-term cardiac events.

We aimed to study the consequences and late outcomes of patients who experienced peripheral vascular complications (PVCs) following percutaneous coronary interventions (PCI). A retrospective analysis of the medical records of 10,669 patients who underwent PCI and experienced PVC between 1995 and 2002 was conducted. One thousand ninety-six patients (10.27% of the study cohort) had PVC post-PCI. After PCI, patients with PVC had higher rates of in-hospital complications (P < 0.001) when compared to patients without PVC, including Q-wave myocardial infarction (MI; 1.2% vs. 0.3%), coronary artery bypass grafting (CABG; 3.8% vs. 0.6%), and death (4.0% vs. 1.0%). At 1-year follow-up, late complications of MI (37.4% vs. 25.4%), non-Q-wave MI (34.9% vs. 22.7%), death (12.9% vs. 5.9%), and CABG (5.7% vs. 4.5%) were higher (< 0.001) in patients with PVC compared to those without. Multivariate analysis identified PVC as a significant predictor of 1-year mortality (P = 0.045). This study underscores the need to make diligent efforts to minimize PVC and follow up these patients for future coronary events. Cardiovasc Interv 2004;62:181–185. © 2004 Wiley-Liss, Inc.
Three-dimensional asymptotic stress field in the vicinity of the line of intersection of a circular cylindrical through/part–through open/rigidly plugged hole and a plate

Heretofore unavailable asymptotic solutions to a class of problems pertaining to the stress fields in the neighborhood of the circumferential corner line or line of intersection of a circular cylindrical through or part-through (embedded) open or rigidly plugged hole and a bounding or interior surface of an isotropic plate, subjected to far-field extension-bending (mode I), inplane shear-twisting (mode II) and torsional (mode III) loadings, are presented. A local orthogonal curvilinear coordinate system (ρ,φ,θ), is selected to describe the local deformation behavior of the afore-mentioned plate in the vicinity of the afore-mentioned circumferential corner line. One of the components of the Euclidean metric tensor, namely g33, is approximated (ρ/a⋘1) in the derivation of the kinematic relations and the ensuing governing system of three partial differential equations. Nine different combinations of boundary conditions are considered, five of which relate to a through hole or infinitely rigid inclusion, while the remaining four pertain to a part–through (embedded) hole or infinitely rigid inclusion. Numerical results presented include the effect of Poisson's ratio, wherever applicable, on the computed lowest eigenvalue(s).
Religious Doubt, Financial Strain, and Depressive Symptoms Among Older Mexican Americans.

A number of studies suggest that various positive aspects of religion help older people cope more effectively with stress. However, the literature further indicates that religion may have negative as well as positive influences in the stress process. This suggests that instead of enhancing coping efforts, religion may also exacerbate the effects of stress. The purpose of this study was to see if one negative aspect of religion (i.e., religious doubt) exacerbates the effects of financial strain on depressive symptoms among older Mexican Americans. A nationwide survey of 1005 older Mexican Americans was conducted. The findings suggest that the effects of financial strain on depressive symptoms are stronger for older Mexican Americans who have more doubts about religion. This study aims to contribute to the literature by assessing the negative aspects of religion with data provided by an ethnic group that has been largely overlooked in the literature.
Investigation of vegetable‐oil‐based coupling agents for kenaf‐fiber‐reinforced unsaturated polyester composites

Kenaf fibers are modified with three novel coupling agents that consist of an isocyanate and acrylated epoxidized soybean oil. The untreated-kenaf-UPE (unsaturated polyester) composites and coupling-agent-treated-kenaf-UPE composites are obtained by a compression molding process. Modifications of kenaf fibers with coupling agents significantly increase mechanical properties, and enhance water resistance of the resulting kenaf-UPE composites. Characterization of coupling-agent-treated-fibers with Fourier transform infrared spectroscopy reveals that coupling agents are covalently bonded onto kenaf fibers. Improved interfacial adhesion between kenaf fibers and UPE resin is confirmed with scanning electron microscopy. The mechanisms on which the chemical treatments of kenaf fibers improve the mechanical properties and water resistance are discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Distinct mechanisms of cAMP induction by constitutively activating LH receptor and wild-type LH receptor activated by hCG.

Asp578Gly is the major mutation of luteinizing hormone (LH) receptors in humans. It is a dominant mutant, constitutively activates Gαs, and induces cAMP production in the absence of the cognate hormone, causing the familial male precocious puberty. The mechanism of the elevated basal cAMP level is unclear. Our data show strikingly different mechanisms between the elevated basal cAMP induced by the activating mutant and the cAMP induced by the wild-type receptor activated by human chorionic gonadotropin (hCG) binding. The study suggests an approach to attenuating the elevated basal cAMP of the activating mutant LH receptor, which could be useful for controlling the familial male precocious puberty. For the study, we used the C-terminal peptides of Gαs and Gαi2, which couple to the receptor.
Beyond Glass Transitions: Studying the Highly Viscous and Elastic Behavior of Frozen Protein Formulations Using Low Temperature Rheology and Its Potential Implications on Protein Stability

Purpose A novel application of oscillatory shear rheology was used to directly monitor global phase behavior of protein formulations in the frozen state and study its correlation with physical instability of frozen protein formulations.
Traffic regulation under the percentile-based pricing policy

With the emerging concept of utility computing, appropriate business models are becoming more and more important for the Internet services. Internet Service Providers (ISP) measure IP network usage for billing in different ways. Percentile-based pricing policy is one of the common billing methods. Percentile-based measurement allows the ISP to bill the customer for the maximum bandwidth used during the billing period while forgiving a small amount of bandwidth spiking. In this paper, we investigate how a customer can regulate the traffic volume under the constraint of a predetermined budget such that the amount of band-width spiking is within the range that the ISP can tolerate. Optimal solutions are presented for the offline case where the traffic demands in each small period are given. A traffic scheduling algorithm is given for the online case where the traffic demands in each small period are unknown in advance. Computations are conducted to illustrate the effectiveness of our solutions.
A novel strategy for segmentation of magnetic resonance (MR) images corrupted by intensity inhomogeneity artifacts

Magnetic resonance images are often corrupted by intensity inhomogeneity (i.e., bias field effects), which manifests itself as slow intensity variations over the image domain. Such shading artifacts must be corrected before performing computerized analyses such as intensity-based segmentation and quantitative analysis. In this paper, we present a novel strategy in the fuzzy c-means (FCM) framework that simultaneously estimates the bias field while segmenting the image. An additive field term that models the bias field is incorporated into the FCM objective function. We propose a new term based on the spectral parameterization (i.e., wavelet coefficients) of the bias field that serves as a regularizer to enforce the smoothness of the estimated bias field. We also introduce a second regularization term that causes the labeling of each pixel to be influenced by its immediate neighborhood pixels. The latter regularization term renders the algorithm less sensitive to noise. We show that the novel objective functional could be optimized efficiently using an iterative process. The efficacy of the algorithm is demonstrated on synthesized images as well as on clinical breast MR images. With the synthesize images, segmentation accuracy using standard FCM is 89.07% while segmentation accuracy with the proposed algorithm is 99.95%.
Theory of nonlinear systems

Abstract This paper gives a general review of the Theory of Nonlinear Systems. In 1960, the author presented a paper “Theory of Nonlinear Control” at the First IFAC Congress at Moscow. Professor Norbert Wiener, who attended this Congress, drew attention to his work on the synthesis and analysis of nonlinear systems in terms of Hermitian polynomials in the Laguerre coefficients of the past of the input. Wiener's original idea was to use white noise as a probe on any nonlinear system. Applying this input to a Laguerre network gives u1, u2,…, us, and then to a Hermite polynomial generator gives V(α)'s. Applying the same input to the actual nonlinear system gives output c(t). Putting c(t) and V(α)'s through a product averaging device, we get c(t)V(α) = A α 2л s 2 , where the upper bar denotes time average and Aα's can be considered as characteristic coefficients of the nonlinear system. A desired output z(itt) may replace c(itt) to get a new set of Aα's. The Volterra functional method suggested by Wiener in 1942 has been greatlydeveloped from 1955 to the present. The method involves a multi-dimensional convolution integral with multi- dimensional kernels. The associated multi-dimensional transforms are given by Y.H. Ku and A.A. Wolf (J. Franklin Inst., Vol. 281, pp. 9–26, 1966). Wiener extended the Volterra functionals by forming an orthogonal set of functionals known as G-functionals, using Gaussian white noise as input. Volterra kernels and Wiener kernels can be correlated and form the characteristic functions of nonlinear systems. From an extension of the linear system to the nonlinear system, the input-output crosscorrelation φxy can be shown to be equal to the convolution of system impulse response h1 with the autocorrelation φxx. Using the white noise as input, where its power density spectrum is a constant, say, A, the crosscorrelation is given by φxy(σ) = Ah1(σ), while the autocorrelation is φxx(τ) = Au(τ). This extension forms the basis of an optimum method for nonlinear system identification. Measurement of kernels can be made through proper circuitry. Parallel to the Volterra series and the Wiener series, another series based on Taylor-Cauchy transforms developed since 1959 are given for comparison. The Taylor-Cauchy transform method can be applied in the analysis of simultaneous nonlinear systems. It is noted that the Volterra functional method and the Taylor-Cauchy transform method give identical final results. A selected Bibliography is appended not only to include other aspects of nonlinear system theory but also to show the wide application of nonlinear system characterization and identification to problems in biology, ecology, physiology, cybernetics, control theory, socio- economic systems, etc.
The experimental analysis of certain aspects of an aphasic's recovery

Abstract This paper describes the experimental analysis of certain aspects of the recovery of an aphasic patient. Specifically, this study focused on the extent to which a psycholinguistic principle could predict a particular facet of the aphasic's recovery; and the utility of reaction time as a measure of the recovery from aphasia. The subject of this investigation was a 21-year-old female, who developed aphasia consequent to the ligation of a cerebral aneurysm. The patient was administered an auditory word comprehension test during the sixth week of therapy. It was found that an inverse relation existed between the subject's reaction times in responding to the test items, and the familiarity of those words. During the seventh month of treatment, the auditory word comprehension test was re-administered to the subject. A statistically significant decrement in reaction times was noted from the original to the second auditory word comprehension testing. This improved latency was taken as an indication of the patient's recovery from her language impairment.
Macromolecule-suppressed GABA-edited magnetic resonance spectroscopy at 3T

Edited magnetic resonance spectroscopy makes possible noninvasive studies of the role of the inhibitory neurotransmitter GABA in the healthy brain and in disease processes. A major limitation of the methodology is coediting of macromolecular signals. Although it has previously been shown that macromolecular signal can be suppressed using a symmetrical editing scheme, this approach is rarely applied at field strength of 3T as insufficiently selective pulses result in loss of GABA signal (in addition to the intended suppression of macromolecular signal). In this article, the authors show that increasing the echo time to 80 ms lets more selective editing pulses be used, allowing for symmetric editing-based suppression of coedited macromolecular signal without loss of GABA signal. The method is applied to acquire macromolecule-suppressed GABA-edited spectra in 10 healthy participants.
Brain catecholamines mediate the delayed reduction in renin release after injection of fenfluramine.

Abstract The present studies examined whether brain or peripheral catecholaminergic mechanisms mediate the fenfluramine-induced reduction in plasma renin activity and concentration. Fenfluramine reduced plasma renin activity and concentration to 35% of basal levels in vehicle pretreated rats. This reduction was prevented in rats whose central catecholaminergic neurons were destroyed by i.c.v. injection of 6-hydroxydopamine (6-OHDA) two weeks prior to the experiment. In contrast, the suppressive effects of fenfluramine on plasma renin activity and concentration was not altered in rats that were surgically adrenal medullectomized and chemically sympathectomized by 6-OHDA. To determine whether α 2 adrenoceptors mediate the suppressive effects of fenfluramine, rats were pretreated with increasing doses of the α 2 adrenoceptor antagonist yohimbine 1 h before the administration of fenfluramine. Although yohimbine alone increased plasma renin activity and concentration, it did not prevent the suppressive effects of fenfluramine. In conclusion, the data suggest that central, but not peripheral catecholamines mediate the suppressive effect of fenfluramine on renin secretion. This effect is not mediated by α 2 adrenoceptors.
Treatment of Crohn's Disease of Inflammatory, Stenotic, and Fistulizing Phenotypes.

The heterogeneous nature of Crohn’s disease (CD) is reflected in the diversity of treatment options available for individual patients. The stratification of CD patients into more homogeneous groups based on disease location and disease behavior may provide clinicians with a more focused approach to therapeutic decision-making. Uncomplicated disease behaviors are typically treated medically. When complications arise and patterns of disease become more aggressive, combined medical and surgical approaches are often necessary and yield favorable results. The surgical management of CD can be as complex as the disease itself, and should involve a surgeon who professes a special expertise in inflammatory bowel disease. Progress in our understanding of the role of the interaction between the environment and the immune system in disease development has led to major advancements in the area of CD therapeutics. Current therapies target the various elements of the inflammatory cascade implicated in the pathogenesis of CD. The anti-inflammatory properties of the pharmacologic therapies presented in this review vary from actions that are extremely broad to those that are cellular or cytokine specific. Maximizing the efficacy of CD-directed therapies while minimizing their toxicity remains the principal objective in developing management strategies for CD patients. Maintaining good quality of life and maximizing adherence to therapies are also important considerations. Despite the various therapeutic options available for CD patients, chosen therapies should be based on the overall treatment goal for individual patients. Therapeutics can be broadly categorized as induction therapies (goal to treat active disease) and maintenance therapies (goal to prevent relapse of disease).
Antithrombin histidine variants 1H NMR resonance assignments and functional properties

Three variants of the 57.5 kDa human plasma proteinase inhibitor antithrombin, H1Q, H65C, and H120C, have been expressed in baby hamster kidney cells to permit assignment of the 1H NMR resonances from the three histidines and evaluation of the role of these histidines in heparin binding. The NMR assignments have enabled more definitive interpretation of previous NMR-based studies of human antithrombin to be made. Although resonances of all three histidines are perturbed by heparin binding, only histidine 120 plays a significant role in the heparin binding site. The perturbations of resonances from histidines 1 and 65 indicate proximity to the heparin binding site and consequent sensitivity to the presence of heparin.
Performance of a Virtual Cluster in a General-Purpose Teaching Laboratory

Through virtualization, a Beowulf cluster running on the physical hardware and network of a general purpose teaching laboratory can provide significant computational power without compromisingâ"in fact increasingâ"the educational value of the lab machines. After describing our implementation of such a virtual cluster in a teaching lab, we analyze its performance by comparing benchmark results to those of an equivalent dedicated (native) cluster and investigate expedient improvements to our design.
Active immunotherapy of L1210 leukemia with neuraminidase-treated, drug-resistant L1210 sublines

The effectiveness of neuraminidase-treated, drug-resistant L1210 sublines in active immunotherapy of L1210 leukemia was evaluated. Optimal conditions for the establishment of in vitro, drug-resistant cells included (a) proper drug concentration, (b) the use of logarithmic-phase cultures in fresh medium, containing 5 or 10% serum, and (c) continual exposure to drug. Active immunotherapy, after tumor burden was reduced with chemotherapy, with neuraminidase-treated cells alone was either effective or deleterious, depending upon the drug-resistant subline used for immunization. The combination of BCG and neuraminidase-treated cells was superior to treatment with chemotherapy only. Optimal response was observed with the use of parental L1210 cells, combined with BCG, in immunotherapy of parental L1210 tumor. The results emphasize that an important prerequisite to successful immunotherapy is that tumor vaccines must elicit immunologic products which are cytotoxic for residual tumor.
High performance III–V FETs for low power CMOS applications

III–V compound semiconductor based quantum well field effect transistors are in general viewed as a promising transistor candidate for future high-speed low-power logic applications due to their excellent drive current performance at low voltage. In this presentation, I will review recent device developments of n-channel InGaAs transistors. To start, well-studied Schottky gate device architecture is adopted to demonstrate integration on Si substrate [1] as well as to establish performance advantages over state-of-the-art Si NMOS at V CC =0.5V [2]. To enable further L G scaling, high quality high-K dielectric is integrated [3] and non-planar Tri-gate architecture is implemented [4]. I will conclude by discussing InSb based p-channel device results [5], as well as InGaAs based tunnel FETs [6].
One dimensional lattice gases with rapidly decreasing interaction

We consider the pressure and the correlation functions of a one dimensional lattice gas in which the mutual interaction decreases as r exp-nt, (r, t>0), when the interparticle distance n→∞. We prove that such a system cannot show phase transitions of order k≧1 in the sense that the pressure and the correlation functions are infinitely differentiable with respect to any relevant parameter (such as the temperature or the chemical potential).
The impact of topology in robust routing on wireless mesh networks

Topology is an essential consideration in the performance of a Wireless Mesh Network, going hand-in-hand with routing. Existing works on routing typically assume topology is a known input which is given in advance and compute routes accordingly. However, in reality considerable freedom exists in node placement with the possibility of creating topologies of varying performances. As the joint topology and routing problem is largely an open issue for conventional wireless mesh networks, these choices may harbor a significant unrealized potential for improvements. In this paper, we explore the impact of node distribution on routing performance in a wireless mesh network by using a novel model to parameterize node placement in a topology. We then evaluate our model using a simulation study and discover a strong correlation between parameter choice and network performance.
Using freelisting to understand shared decision making in ADHD: parents' and pediatricians' perspectives.

Objective To compare and contrast notions of ADHD among pediatricians and parents of affected children to understand the perspectives they bring to shared decision making (SDM).