cssi/SciSciGPT-SciSciNet huggingface dataset:
Online completion of Ill-conditioned low-rank matrices

We consider the problem of online completion of ill-conditioned low-rank matrices. While many matrix completion algorithms have been proposed recently, they often struggle with ill-conditioned matrices and take a long time to converge. In this paper, we present a new algorithm called Polar Incremental Matrix Completion (PIMC) to address this problem. Our method is based on the GROUSE algorithm, and we show how a polar decomposition can be used to maintain an estimate of the singular value matrix to better deal with ill-conditioned problems. The method is also online, allowing it to be applied to streaming data. We evaluate our algorithm on both synthetic data and a real "structure from motion" dataset from the computer vision community, and show that PIMC outperforms similar methods.
The use of gadolinium-enhanced magnetic resonance imaging to determine lesion site in traumatic facial paralysis

Gadolinium-enhanced magnetic resonance imaging has been used to evaluate 20 patients with surgically confirmed facial nerve lesions. When the nerve could be seen, gadolinium-enhanced magnetic resonance imaging accurately revealed the lesion site as well as the known extent, which in some cases was not predicted by topognostic testing. This technique appears to provide accurate lesion-site testing and may have importance in surgical planning. Currently used topognostic tests of facial nerve function are frequently inaccurate and can only determine the most proximal lesion site when there are multiple or extensive lesions. The focal nerve enhancement seen in nerve injury, globally increased signal intensity within the temporal bone after trauma, and increased signal intensity within the dura after surgery can occasionally mask nerve lesions and may be confused with tumors.
Retroactive Antijamming for MISO Broadcast Channels

Jamming attacks can significantly impact the performance of wireless communication systems. In addition to reducing the capacity, such attacks may lead to insurmountable overhead in terms of retransmissions and increased power consumption. In this paper, we consider the multiple-input single-output (MISO) broadcast channel (BC) in the presence of a jamming attack in which a subset of the receivers can be jammed at any given time. Further, countermeasures for mitigating the effects of such jamming attacks are presented. The effectiveness of these antijamming countermeasures is quantified in terms of the degrees-of-freedom (DoF) of the MISO BC under various assumptions regarding the availability of the channel state information (CSIT) and the jammer state information at the transmitter (JSIT). The main contribution of this paper is the characterization of the DoF region of the two user MISO BC under various assumptions on the availability of CSIT and JSIT. Partial extensions to the multiuser broadcast channels are also presented.
Reconfigurable visible quantum dot microlasers integrated on a silicon chip

Developing on-chip, dynamically reconfigurable visible lasers that can be integrated with additional optical and electronic components will enable adaptive optical components. In the present work, we demonstrate a reconfigurable quantum dot laser based on an integrated silica ultra high-Q microcavity. By attaching the quantum dot using a reversible, non-destructive bioconjugation process, the ability to remove and replace it with an alternative quantum dot without damaging the underlying microcavity device has been demonstrated. As a result of the absorption/emission characteristics of quantum dots, the same laser source can be used to excite quantum dots with distinct emission wavelengths.
π-Acid Ligands in Iron(III) Porphyrinates. Characterization of Low-Spin Bis(tert-butylisocyanide)(porphyrinato)iron(III) Complexes Having (dxz,dyz)4(dxy)1 Ground States

The synthesis and characterization of isocyanide complexes of (porphyrinato)iron(III) species, [(Porph)Fe(t-BuNC)2]ClO4, Porph = OEP, TPP, are reported. The crystal structures of [(TPP)Fe(t-BuNC)2]...
1160 AN IN VITRO MODEL FOR ASSESSING ANTIMICROBIAL ACTIVITY DURING PERITONEAL DIALYSIS

An in vitro model was designed for evaluating various parametersof infection and antimicrobial therapy during peritoneal dialysis (PD). The system includes a dialysis membrane sack containing commercially prepared dialysis fluid (DF) suspended in pooled human plasma, enclosed in a cylindrical flask. Ports through a rubber stopper were devised for bacterial inoculation, drug injection, and sample collection. By 6 hrs the simulated dialysis achieved pH, osmolarity, glucose, Mg++ and Ca++ values comparable to those of recovered peritoneal fluid (RPF) from patients undergoing PD. When antimicrobials (tobramycin [TOB] 8 μg/ml, piperacillin [PIP] 200 μg/ml, ceftazidime [CTZ] 100 μg/ml, or ciprofloxacin [CIP] 2 μg/ml) were added to the DF within the dialysis membrane sack, 75% of PIP and CTZ and 50% of TOB and CIP diffused into the surrounding plasma by 6 hrs. This is comparable to clinical experience with i.p. TOB or β-lactams. The bactericidal rate of the above drugs against 10 cfu/ml of P. aeruginosa was measured in DF during 6 hrs dialysis and was similar to killing kinetics in RPF from patients (no kill by PIP, <99% kill by CTZ, ≥99.9% kill by TOB and CIP). Maintaining CIP concentrations of 2 μg/ml in DF yielded ≥99.9% kill of E. coli, K. pneumoniae, S. epidermidis, and S. aureus within 2 hrs. This in vitro model may be useful in studying the kinetics of antimicrobial activity and designing studies of antimicrobial therapy for PD-related peritonitis.
Use of multiphoton laser scanning microscopy to image benzo[a]pyrene and metabolites in fish eggs

Multiphoton laser scanning microscopy (MPLSM) is a promising tool to study the tissue distribution of environmental chemical contaminants during fish early life stages. One such chemical for which this is possible is benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon that absorbs strongly at UV wavelengths and fluoresces following multiphoton excitation. BaP is enzymatically converted to hydroxylated metabolites, which are further modified to more polar conjugates. To determine whether fluorsecent signal from parent compound and metabolites could be differentiated by MPLSM, multiphoton excitation spectra were determined from 730-880 nm using a tunable Ti:Sapphire laser. BaP-3-hydroxy (BaP-3-OH) was the most fluorescent and the two conjugated metabolites, BaP-3-sulfate and BaP-3-glucuronide, exhibited fluorescence intensity intermediate between BaP and BaP-3-OH. For example, at 760 nm the fluorescence of conjugated metabolites was four-fold greater, while BaP-3-OH exhibited 16-fold greater fluorescent intensity than BaP. At wavelengths longer than 830 nm there was no excitation of BaP above background. Spectral differences at the longer wavelengths were used to detect the presence of the primary metabolite BaP-3-OH in the presence of parent or conjugated metabolites in fish egg homogenates. Thus, multiphoton excitation spectral characteristics can provide a means to follow the tissue distribution of parent and metabolite in developing fish.
Simultaneous infection with and

In this report, we present two cases of simultaneous infection with Blastomyces dermatitidis and Cryptococcus neoformans. In both cases, fungi were isolated from the lungs. The clinical manifestations were not suggestive of infection with two fungi. One patient was receiving immunosuppressive therapy and another was otherwise immunocompetent. A review of the literature failed to uncover any reports of co-infection with these two fungal pathogens. We discuss possible mechanisms for the isolation of both pathogens.
Images in clinical medicine. Echinococcal cyst of the pericardium.

Figure 1. A 56-year-old man from Saudi Arabia presented with dyspnea. A chest film (Panel A) revealed a large mass in the left hemithorax, with contralateral mediastinal shift and depression of the gas-filled stomach (arrow). Computed tomography after the injection of intravenous contrast medium (Panel B and Panel C) showed a large multilocular cyst in the left hemithorax with contralateral displacement of mediastinal structures, including the trachea (T), the ascending aorta (AA) and the descending aorta (DA), the superior vena cava (SVC), and the right pulmonary artery (RPA). The left main bronchus (arrow) and left pulmonary artery (LPA) were compressed. . . .
Feasibility of Spectroscopic Characterization of Algal Lipids: Chemometric Correlation of NIR and FTIR Spectra with Exogenous Lipids in Algal Biomass

A large number of algal biofuels projects rely on a lipid screening technique for selecting a particular algal strain with which to work. We have developed a multivariate calibration model for predicting the levels of spiked neutral and polar lipids in microalgae, based on infrared (both near-infrared (NIR) and Fourier transform infrared (FTIR)) spectroscopy. The advantage of an infrared spectroscopic technique over traditional chemical methods is the direct, fast, and non-destructive nature of the screening method. This calibration model provides a fast and high-throughput method for determining lipid content, providing an alternative to laborious traditional wet chemical methods. We present data of a study based on nine levels of exogenous lipid spikes (between 1% and 3% (w/w)) of trilaurin as a triglyceride and phosphatidylcholine as a phospholipid model compound in lyophilized algal biomass. We used a chemometric approach to corrrelate the main spectral changes upon increasing phospholipid and triglyceride content in algal biomass collected from single species. A multivariate partial least squares (PLS) calibration model was built and improved upon with the addition of multiple species to the dataset. Our results show that NIR and FTIR spectra of biomass from four species can be used to accurately predict the levels of exogenously added lipids. It appears that the cross-species verification of the predictions is more accurate with the NIR models (R2 = 0.969 and 0.951 and RMECV = 0.182 and 0.227% for trilaurin and phosphatidylcholine spike respectively), compared with FTIR (R2 = 0.907 and 0.464 and RMECV = 0.302 and 0.767% for trilaurin and phosphatidylcholine spike, respectively). A fast high-throughput spectroscopic lipid fingerprinting method can be applied in a multitude of screening efforts that are ongoing in the microalgal research community.
The response of leaf resin to artificial herbivory in Eriodictyon californicum

Herbivore damage induces the production of defensive chemicals in many plant species. However, defensive chemicals sometimes have functions other than protection from herbivores, and these chemicals may respond to hervibory differentialy than those which are primarily defensive. A well-studied group of leaf constituents with multiple functions is the phenolic leaf resins, which protect leaves from herbivores, UV radiation, and possibly excess water loss. The effects of herbivory on phenolic leaf resins were investigated in the chapparral shrub Eriodictyon californicum by artificially damaging leaves during the growing season and subsequently measuring resin content and composition. We found that (i) resin content declined in leaves damaged by artificial herbivory; (ii) resin declined (at the P < 0.1 level) in undamaged leaves present on the same plant as those heavily damaged; and (iii) resin composition, as measured by the ratio of the major components, was unaffected by artificial herbivory.
Substituted M x Cu6 − x Sn5 Compounds (M = Fe , Co, Ni, Zn) Designing Multicomponent Intermetallic Electrodes for Lithium Batteries

A strategy to exploit substituted M x Cu 6-x Sn 5 (M = Fe, Co, Ni, Zn) electrodes with NiAs-type structures that transform on electrochemical lithiation in lithium cells to intermediate face-centered-cubic Li 2 Cu 1-y M y Sn structures before Li z Sn alloys (1 < z < 4.4) are produced is discussed. Zn substitution for Cu is possible only to x as 1 before the onset of secondary phases, whereas Co and Ni substitution appears to maintain the NiAs-type structure for the whole range of x (0 ≤ x ≤ 5). Substituted electrodes provide higher rechargeable capacities than Cu 6 Sn 5 . The results of the study have implications for tailoring and optimizing (i) the design of multicomponent intermetallic electrode structures containing elements that are either active or inactive towards lithium, (ii) electrode compositions, and (iii) the reversibility of lithium insertion/metal displacement reactions in intermetallic electrode systems.
Preservers of spectral radius, numerical radius, or spectral norm of the sum on nonnegative matrices

Abstract Let M n + be the set of entrywise nonnegative n × n matrices. Denote by r ( A ) the spectral radius (Perron root) of A ∈ M n + . Characterization is obtained for maps f : M n + → M n + such that r ( f ( A ) + f ( B ) ) = r ( A + B ) for all A , B ∈ M n + . In particular, it is shown that such a map has the form A ↦ S - 1 AS or A ↦ S - 1 A tr S , for some S ∈ M n + with exactly one positive entry in each row and each column. Moreover, the same conclusion holds if the spectral radius is replaced by the spectrum or the peripheral spectrum. Similar results are obtained for maps on the set of n × n nonnegative symmetric matrices. Furthermore, the proofs are extended to obtain analogous results when spectral radius is replaced by the numerical range, or the spectral norm. In the case of the numerical radius, a full description of preservers of the sum is also obtained, but in this case it turns out that the standard forms do not describe all such preservers.
Effect of amantadine on motility of reserpinized mice as a function of brain biogenic amines and mouse strains

The effect of amantadine, reserpine or both on locomotor activity and whole brain content of selected biogenic amines and major metabolites was studied as a function of mouse strain. Successive administration of small dose regimens of reserpine, 0.2 mg/kg IP, did not alter motility from corresponding saline control. Administration of amantadine, 100 mg/kg, IP, prior to each of the reserpine treatments produced either stimulation of motor activity in the albino ICR and black C57BL/6 mice or caused inhibition from reserpine in the albino BALB/C and the brown CDF-1 mouse strains. This suggests a genotype strain sensitivity to the amantadine and reserpine interaction on the motor behavior of the mouse. The amantadine treatment did not alter brain dopamine concentration but increased its immediate acid metabolite, 3,4-dihydroxyphenylacetic acid, in the C57BL/6 mice as contrasted with reduction of the same in the BALB/C mouse strain. Both BALB/C and C57BL/6 mice showed changes in brain normetanephrine levels as a consequence of the pharmacologic intervention used which suggest catecholaminergic sensitivity. The only changes produced by the agents studied in brain serotonin or 5-hydroxyindoleacetic acid levels were confined to the BALB/C mouse strain. No changes occurred in brain levels of the compounds measured from corresponding controls in the CDF-1 mice. The results indicate differential sensitivity of the serotonergic and dopaminergic systems to drug-drug interaction studied which appears to be strain dependent.
Angiotensin II receptor-mediated proliferation of cultured human fetal mesangial cells

Angiotensin II receptor-mediated proliferation of cultured human fetal mesangial cells. Accumulating evidence suggests that angiotensin II (Ang II) may play an important role in renal growth and glomerular development. During nephrogenesis, a complex relationship between the capillary and renal mesangium develops. Since the mesangial cell is a centrally-located pericyte with contractile, endocrine, and immune modulating functions, it may play a unique role in maintaining normal glomerular function. Therefore, we examined whether Ang II affects proliferation of human fetal mesangial cells in vitro and compared these findings to mesangial cells isolated from adult kidney. In these primary isolates, we studied the relationship between Ang II receptors and the mitogenic activity of angiotensin. Scatchard analysis of the binding of 125 I[Sar 1 ,Ile 8 ]Ang II to subconfluent cultured human fetal mesangial cells revealed the presence of one class of binding sites with a Kd of 1.25 nm and a B max of 70 fmol/1 × 10 5 cells. Ang II receptors on adult mesangial cells had similar binding kinetics with a Kd of 1.6 nM and Bmax of 65 fmol/10 5 cells in subconfluent culture. In subconfluent culture of fetal mesangial cells, Ang II increased [ 3 H]thymidine incorporation by 130% (P 3 H]thymidine incorporation by only 35%(P 1 ,Ile 8 ]Ang II (1 µm) inhibited the mitogenic response of fetal mesangial cells to Ang II. Ang II increased fetal mesangial cell number by 25% (after 4 days) in serum-free medium supplemented with insulin or supplemented with insulin and 1% Nutridoma (P
Pitting-Resistant Alloys in Highly Concentrated Chloride Media

Abstract The pitting resistance of a series of experimental stainless steels with varying amounts of nickel, chromium, molybdenum, manganese, and nitrogen and a number of commercial stainless steel...
Organizational ambidexterity: Integrating deliberate and emergent strategy with scenario planning

In this article we propose scenario planning as a tool for fostering organizational ambidexterity. The concept of organizational ambidexterity continues to gain attention, however, clear methods for developing this organizational ability are generally not offered. We therefore describe organizational ambidexterity and situate it in the general strategy literature. Key characteristics of organizational ambidexterity are provided, and the logical link to scenario planning is made. As the concept of organizational ambidexterity is relatively novel, our proposal highlights the use of scenario planning as a potential tool for developing this organizational “skill”, and clear next steps are described to examine our proposal as well as leverage the concept of organizational ambidexterity beyond that of a simple metaphor.
A Legendre Wavelet Method for the Radiative Transfer Equation in Remote Sensing

An approximate method for solving radiative Transfer equation in a slab medium with an isotropic scattering is presented. The method is based upon Legendre wavelets approximations. The differential and integral expressions which arise in the radiative transfer equation are converted into some linear systems of differential equations which can be solved for the unknown coefficient. Numerical examples are included to demonstrate the validity and applicability of the technique and a comparison is made with existing results.
Effects of Technology Cycles on Strategic Alliances

This study examines various issues related to the formation of strategic alliances by using the cyclical model of technological change constructed by Tushman & Anderson (1986). Technology cycles offer a useful evolutionary perspective on shaping technology trajectories. The evolution of technology is a result of technological, social and political factors. The four stages in the model include technological variation (stage I), era of ferment (stage II), technology selection (stage III), and technology retention (stage TV). Within each of the four stages, issues related to the formation of strategic alliances - motivations, governance modes, and the selection of partners - are explored. The association between the cyclical model of technological change and the formation of alliances is empirically tested in response to the statement that a missing link exists for empirically validating the model of technology cycles. Specific research questions include: How will the context of cyclical stages of technological change affect the formation of strategic alliances? In other words, will different types of resources and capabilities be most valuable at different stages of technological change? How well does Tushman and Anderson's theory of technology cycles explain technology's impact on the formation of strategic alliances? Data were 594 alliances in the semiconductor industry from the Securities Data Corporation. Findings showed that the model of technological change is a useful framework in studying strategic alliances. More specifically, at the technology variation stage, innovation-driven alliances are the most important motives. Firms lack of promising technologies tend to select firms with promising technologies. Firms with promising technologies tend to select firms with complementary capabilities. At the era of ferment, both innovation- and efficiency-driven alliances for old technologies are the most important motives. Dominant industry players in either the semiconductor industry or other industries surprisingly are not the favorable alliance partners. At the stage of technology selection, manufacturing-type of alliances for new technologies are the most important motives. The more frequently adopted alliance modes are the ones with high control mechanisms and with equity involvement. Partners located either upstream or downstream the focal firm are the most favorable choices. At the technology retention stage, market-driven alliances are the most important motives. However, firms in different industries or established firms in targeted markets are not favorable alliance partners. This study contributes to the literature in two ways: First, it empirically tested the cyclical model of technological change by Tushman and Anderson (1986) and linked the effects of technology cycles with studies on strategic alliances. Second, it empirically validates the argument that certain types of resources are most advantageous under particular technological conditions at various stages of technology cycles. The model provides rich settings to study how firms cope with their technical environment.
Multimedia medical archiving system

The demand for digital radiological imaging and archiving applications has been increasingly rapidly. These digital applications offer significant advantages to the physician over the traditional film-based technique. They result in faster and better quality services, support remote access and conferencing capabilities, provide on demand service availability, eliminate film processing costs, and most significantly, they are suitable services for the evolving global information super highway. Several existing medical multimedia systems incorporate and utilize those advanced technical features. However, radiologists are seeking an order of magnitude improvement in the overall current system design and performance indices (such as transactions response times, system utilization and throughput). One of the main technical concern radiologists are raising is the miss-filing occurrence. This even will decrease the radiologist productivity; introduce unnecessarily workload; and will result in total customer dissatisfaction. This paper presents Multimedia Medical Archiving System, which can be used in hospitals and medical centers for storing and retrieving radiological images. Furthermore, this paper emphasizes a viable solution for the miss-filing problem. The results obtained demonstrate and quantify the improvement in the overall radiological operations. Specifically this paper demonstrates an order of 80% improvement in the response time for retrieving images. This enhancement in system performance directly translates to a tremendous improvement in the radiologist's productivity.
Unfaithful minimal Heilbronn characters of finite groups

Abstract We obtain necessary and sufficient conditions for a finite group G to possess an “unfaithful minimal Heilbronn character”—a virtual character but not a character of G whose inner product with every monomial character is nonnegative, whose restriction to every proper subgroup and quotient is a character, and whose restriction to some proper subgroup is unfaithful. We give an application constraining hypothetical minimal counterexamples to Artin's Conjecture on the holomorphy of L -series.
Some new quantum chemical procedures for the analysis of drug—receptor interactions

The interaction of biologically active molecules with macromolecular receptors is analyzed in terms of preferred intermolecular orientation and the resulting intermolecular forces. The concept of an interaction pharmacophore representing a reactivity index for biologically active molecules and the representation of this pharmacophore by molecular electrostatic potentials are discussed and illustrated. A theoretical method for the analysis of multiple-site interactions of large molecules is presented in terms of a double perturbation formalism. The method is applied to the model system of adenine interacting simultaneously with a molecule of water and an approaching proton. The results illustrate a possible mechanism for the preferential activation of secondary sites when a large molecule is already interacting at a primary reactive site.
Theoretical calculations of the helix-coil transition of DNA in the presence of large, cooperatively binding ligands.

Theoretical calculations are conducted on the helix–coil transition of DNA, in the presence of large, cooperatively binding ligands modeled after the DNA-binding proteins of current biological interest. The ligands are allowed to bind both to helx and to coil, to cover up any number of bases or base pairs in the complex, and to interact cooperatively with their nearest neighbors. The DNA is treated in the infinite homogeneous Ising model approximation, and all calculations are done by Lifson's method of sequence-generating functions. DNA melting curves are calculated by computer in order to expolore the effects on the transition of ligand size, binding constant, free activity, and ligand–ligand cooperativity. The calculations indicate that (1) at the same intrinsic free energy change per base pair of the complexes, small ligands, for purely entropic reasons, are more effective than are large ligands in shifting the DNA melting temperature; (2) the response of the DNA melting temperature to increased ligand binding constant K and/or free ligand activity L is adequately represented at high values of KL (but not at low KL) by a simple independent site model; (3) if curves are calculated with the total amount of added ligand remaining constant and the free ligand activity allowed to vary throughout the transition, biphasic melting curves can be obtained in the complete absence of ligand–ligand cooperativity. In an Appendix, the denaturation of poly[d(A-T)] in the presence of the drug, netropsin, is used to verify some features of the theory and to illustrate how the theory can be used to obtain numerical estimates of the ligand binding parameters from the experimental melting curves.
Production of Channel Catfish in Ponds with Water Recirculation

Abstract Recirculation of water in 0.04-ha production ponds was tested in three studies as a means of increasing yield of channel catfish (Ictalurus punctatus). Centrifugal pumps moved water (227 L/min) from the deep to the shallow ends of ponds; water passed through a 1,000-L biofiltration tank in two studies. In each study, 45-g fingerlings were stocked, and market-size fish (>450 g) were produced during 175-d growing seasons. In study 1, stocking rates were 7,410, 12,300, and 17,300 fish/ ha; for each density, three ponds received water recirculation and one (control) pond did not. Yield increased with stocking rate (P 0.05). In study 2, the stocking rate was 14,820 fish/ha; water was pumped 12 h/night in six ponds and continuously in six ponds. Yield did not differ between treatments, indicating continuous pumping was unnecessary. In study 3, the stocking rate was 19,760 fish/ha; water was recirculated 8 h/night in 12 ...
Sodium-induced 2×1→1×1 surface structural transition on Si(111)

Sodium deposited on the cleaved Si(111)2\ifmmode\times\else\texttimes\fi{}1 surface induces a 2\ifmmode\times\else\texttimes\fi{}1\ensuremath{\rightarrow}1\ifmmode\times\else\texttimes\fi{}1 surface structural transition at about 1/2 monolayer coverage. Angle-resolved direct and inverse photoemission reveal the surface to be semiconducting. The measured energy dispersion of the empty Na-induced surface state is only consistent with calculations that favor the threefold-hollow site for the Na adsorption position. Its bonding character (ionic versus covalent) will be discussed.
Deferred data structuring: Query-driven preprocessing for geometric search problems

We consider the problem of answering a series of on-line queries on a static database. The conventional approach to such problems involves a preprocessing phase which constructs a data structure with good search behavior. The data structure is then used to process a series of queries without any further reordering. Our approach involves dynamic or query-driven structuring of the database, i.e. we process the database only when it is required for answering a query. We present optimal algorithms for the following problems in the plane: testing convex hull membership, half-plane intersection queries and fixed-constraint multi-objective linear programming. This technique is also applied to multidimensional dominance query problems.
Influence of ions, inhibitors and anoxia on transtrophoblast potential of rabbit blastocyst

Abstract The influence of ions, metabolic inhibitors and anoxia on the transtrophoblast potential difference (TPD) of the 6 day rabbit blastocyst was studied in vitro. TPD measurements were made using glass microelectrodes with Ag-AgCl wire at the liquid-metal junction. When Cl − is replaced by SO 4 − in the external medium (Krebs Ringer bicarbonate glucose), the steady negative TPD was changed to a positive value. Replacement of Cl − by Br − , NO 3 = or I − decreased the TPD to less than 50% of the normal value. In a medium in which Na + was replaced by lithium the TPD increased by about 30%. K + free Ringer had no effect on the TPD. The TPD was greatly reduced or abolished by anoxia, sodium cyanide, 2,4-dinitrophenol and iodoacetic acid while ouabain increased the TPD by 30%. This TPD is also temperature dependent (Q 10 of 1.7), dropping suddenly at 44 °C. These results suggest that active ionic transport processes may play a role in determining the TPD.
Effect of pH and Gas-Phase Ozone Concentration on the Decolorization of Common Textile Dyes

This paper presents the results of a laboratory study on the effect of pH (2, 5, and 9) and gas-phase ozone concentration (1, 7, and 11 wt %) on the decolorization efficiency via ozonation for seven common textile dyes. Higher gas-phase ozone concentrations resulted in higher decolorization rates due to more rapid ozone transfer. Higher gas-phase ozone concentration, however, was also observed to have a positive, neutral, or negative effect on ozone dose requirements for different dyes. In general, greater ozone utilization efficiency was achieved at lower pH levels where direct ozone reactions predominate. It was observed that because ozonation can cause significant resolubilization of precipitated dyes, complete removal of dye precipitate should be accomplished prior to polishing via ozonation. The results point to the need for laboratory and/or pilot testing for dye-laden wastestreams to allow process optimization.
Gasser-Leutwyler coefficients from partially quenched lattice QCD

Abstract We present the latest results of our ongoing project to determine the Gasser-Leutwyler coefficients of the QCD chiral Lagrangian using partially quenched lattice QCD with three flavors of light dynamical quarks. We are currently studying the mass dependence of the pseudoscalar meson and can extract 2 L 8 − L 5 and 2 L 6 − L 4 . Neither combination can be determined from experimental data alone. While phenomenological estimates have been available for some time, precise ab initio determination of these low energy constants could greatly reduce the theoretical uncertainties of chiral perturbation theory calculations. Our value of 2 L 8 − L 5 is particularly interesting because it rules out the possibility that a massless up quark is responsible for strong CP invariance. We will discuss in some detail the studies we have done to estimate the theoretical uncertainties of our simulations.
A computerized microspectrophotometer using fibre optics for transmission and detection of light

SUMMARY A computerized microspectrophotometer was developed to provide rapid and accurate sequential measurements on cells, including nuclear DNA content, by fluorescence staining, photometric grain counting from autoradiographs, and nuclear size estimated by measurement aperture area. To alleviate bulk and vibrations caused by additional stepper motors, the excitation light and filters as well as the emission filters and photomultipliers were detached from the main microscope frame. The light was directed to and from the microscope through fibre optic bundles. This configuration provided an excellent light gathering faculty and made optical alignment easier. The machine provided highly accurate sequential measurements on a relatively large number of cells by static photometry.
Chronic pain after surgery: What can we do to prevent it?

The development of chronic pain after surgery is not an uncommon event. Despite increased attention devoted to this topic in the recent medical literature, little is known about the underlying mechanisms, natural history, and response to therapy of each syndrome. Central nervous system plasticity that occurs in response to tissue injury may contribute to the development of persistent postsurgical pain. As evidence continues to accumulate concerning the role of central sensitization in the prolongation of postoperative pain, many researchers have focused on methods to prevent central neuroplastic changes from occurring through the use of preemptive or preventative analgesic techniques. Effective preventative analgesic techniques may be useful in reducing not only acute pain but also chronic postsurgical pain and disability. This review examines the efficacy of using a variety of analgesic techniques aimed at preventing or reducing chronic pain after surgery. Specific chronic postsurgical pain syndromes evaluated include complex regional pain syndrome, phantom limb pain, chronic donor site pain, post-thoracotomy pain syndrome, and postmastectomy pain syndrome.
High-molecular-weight immunoreactive beta-endorphin in extracts of human placenta is a fragment of immunoglobulin G

A high-molecular-weight protein with beta-endorphin- and adrenocorticotropin-immunoreactivities was isolated from extracts of human placenta after several purification steps, including immunoadsorption with a well-characterized antiserum raised to beta-endorphin. This protein was identified as the heavy chain of the human immunoglobulin class IgG1. These results have led to the recognition of homologies in the amino acid sequences of these physiologically unrelated molecules. They also suggest caution in accepting immunological competence as the sole criterion of the chemical identity of a ligand.
Relatively small increases in the steady-state levels of nucleobase deamination products in DNA from human TK6 cells exposed to toxic levels of nitric oxide

Nitric oxide (NO) is a physiologically important molecule that has been implicated in the pathophysiology of diseases associated with chronic inflammation, such as cancer. While the complicated chemistry of NO-mediated genotoxicity has been extensively study in vitro, neither the spectrum of DNA lesions nor their consequences in vivo have been rigorously defined. We have approached this problem by exposing human TK6 lymphoblastoid cells to controlled steady-state concentrations of 1.75 or 0.65 μM NO along with 186 μM O2 in a recently developed reactor that avoids the anomalous gas-phase chemistry of NO and approximates the conditions at sites of inflammation in tissues. The resulting spectrum of nucleobase deamination products was defined using a recently developed liquid chromatography/mass spectrometry (LC/MS) method and the results were correlated with cytotoxicity and apoptosis. A series of control experiments revealed the necessity of using dC and dA deaminase inhibitors to avoid adventitious formation of 2′-deoxyuridine (dU) and 2′-deoxyinosine (dI), respectively, during DNA isolation and processing. Exposure of TK6 cells to 1.75 μM NO and 186 μM O2 for 12 hr (1260 μM•min dose) resulted in 32% loss of cell viability measured immediately after exposure and 87% cytotoxicity after a 24 hr recovery period. The same exposure resulted in 3.5-, 3.8-, and 4.1-fold increases in dX, dI and dU, respectively, to reach the following levels: dX, 7 (±1) per 106 nt; dI, 25 (±2.1) per 106 nt; and dU, 40 (±3.8) per 106 per nt. dO was not detected above the limit of detection of 6 lesions per 107 nt in 50 μg of DNA. A 12 hr exposure to 0.65 μM NO and 190 μM O2 (468 μM•min dose) caused 1.7-, 1.8-, and 2.0-fold increases in dX, dI, and dU, respectively, accompanied by a ∼15 (±3.6) % reduction in cell viability immediately after exposure. Again, dO was not detected. These results reveal modest increases in the steady-state levels of DNA deamination products in cells exposed to relatively cytotoxic levels of NO. This could result from limited nitrosative chemistry in nuclear DNA in cells exposed to NO or high levels of formation balanced by rapid repair of nucleobase deamination lesions in DNA.
A comparison of scattering model results for two-dimensional randomly rough surfaces

Bistatic radar cross sections are calculated using two modern scattering models: the small slope approximation (both first- and second-order), and the phase perturbation technique. The problem is limited to scalar-wave scattering from two-dimensional, randomly rough Dirichlet surfaces with a Gaussian roughness spectrum. Numerical results for the cross sections are compared to those found using the classical Kirchhoff, or physical optics, approximation and perturbation theory. Over a wide range of scattering angles, the new results agree well with the classical results when the latter are considered to be accurate. A comparison between the new results shows that the phase perturbation method gives better results in the backscattering region for correlation lengths greater than approximately one wavelength, while both the first- and second-order small slope approximations yield greater accuracy in the forward scattering direction at low grazing angles. >
Initial Acquisition of Mental Graphemic Representations in Children with Language Impairment

Purpose The authors examined initial acquisition of mental graphemic representations (MGRs) for a set of pseudowords in children with language impairment (LI). They also determined whether the ling...
Response conflict and frontocingulate dysfunction in unmedicated participants with major depression

Individuals with major depressive disorder (MDD) often exhibit impaired executive function, particularly in experimental tasks that involve response conflict and require adaptive behavioral adjustments. Prior research suggests that these deficits might be due to dysfunction within frontocingulate pathways implicated in response conflict monitoring and the recruitment of cognitive control. However, the temporal unfolding of conflict monitoring impairments in MDD remains poorly understood. To address this issue, we recorded 128-channel event-related potentials while 20 unmedicated participants with MDD and 20 demographically matched, healthy controls performed a Stroop task. Compared to healthy controls, MDD subjects showed larger Stroop interference effects and reduced N2 and N450 amplitudes. Source localization analyses at the time of maximal N450 activity revealed that MDD subjects had significantly reduced dorsal anterior cingulate cortex (dACC; Brodmann area 24/32) and left dorsolateral prefrontal cortex (Brodmann area 10/46) activation to incongruent relative to congruent trials. Consistent with the heterogeneous nature of depression, follow-up analyses revealed that depressed participants with the lowest level of conflict-related dACC activation 620 ms post-stimulus were characterized by the largest Stroop interference effects (relatively increased slowing and reduced accuracy for incongruent trials). Conversely, MDD participants with relatively stronger dACC recruitment did not differ from controls in terms of interference effects. These findings suggest that for some, but not all individuals, MDD is associated with impaired performance in trials involving competition among different response options, and reduced recruitment of frontocingulate pathways implicated in conflict monitoring and cognitive control.
Deleterious effects of polynuclear aromatic hydrocarbon on blood vascular system of the rat fetus.

BACKGROUND: Polynuclear aromatic hydrocarbons (PAH), benzo[α]pyrene (B[α]P) and 7,12-dimethylbenz[α]anthracene (DMBA) are toxic environmental agents distributed widely. The relative deleterious effects of these agents on growth and blood vasculature of fetus and placental tissues of the rat were studied. METHODS: Pregnant rats (Day 1 sperm positive) with implantation sites confirmed by laparotomy were treated intraperitoneally (i.p.) on Pregnancy Days 10, 12, and 14 with these agents dissolved in corn oil at cumulated total doses 50, 100, and 200 mg/kg/rat, and control with corn oil only (3–20 dams/group). Fetal growth, tissue hemorrhage, and placental pathology were evaluated by different parameters on Pregnancy Day (PD) 20 in treated and control rats. RESULTS: DMBA was relatively more deleterious compared to B[α]P indicated by increased lethality and progressive reduction of body weight of the mother with increasing doses. At 200 mg/kg/rat doses of these agents, maternal survival was 45% and 100% and body weight reduced 24% and 52% of controls, respectively. The fetal survival rates in live mothers were similar to that of controls. They induced marked fetal growth retardation and necrosis of placental tissues. B[α]P and DMBA produced significant toxicity to differentiating fetal blood vascular system as exhibited by rupture of blood vessels and hemorrhage, especially in the skin, cranial, and brain tissues. CONCLUSIONS: Maternal PAH exposure induced placental toxicity and associated adverse fetal development and hemorrhage in different parts of the fetal body, in particular, marked intradermal and cranial hemorrhage, showing that developing fetal blood vasculature is a target of PAH toxicity. Birth Defects Res (PartB), 2007. © 2007 Wiley-Liss, Inc.
Intramolecular Conversions Over Low Barriers IX: Vibrational Bottle-Necks at Statistical Equilibrium

The presence of bottle-necks in IVR rates is indicated by the inverse dependence of a group of bimolecular rate constants on density, at low densities. The previously proposed model for relaxation times of systems in dynamic equilibrium (typical of isomerizations over low barriers) can be extended to make transparent the role of individual vibrational states. A coupling parameter can be explicitly introduced (for each molecular species) which relates the probability for intramolecular energy transfers to the amounts of energy which have to be converted from the non-involved oscillators to the one (υα) which comprises the reaction coordinate (ζ). The essential function is f(q; E), which is the number of states within the interval E and (E + ΔE) [for a total state density g(E)] which incorporate excitation of any particular v, state. The total energy space is divided into a large number of “bands” between which both collisional and collisionless energy transfers take place. The relaxation time is obtained from the lowest non-zero root of a large secular determinant.
Range multicast routers for large-scale deployment of multimedia application

In this paper, we present the Range Multicast protocol and the implemented prototype. We propose to demonstrate the system at the 2004 ACM Multimedia Conference.
The pathogenesis of fibrocystic disease of the pancreas; a study of 36 cases with special reference to the pulmonary lesions.

Pathologic studies and clinical data from 36 fatal cases of fibrocystic disease of the pancreas support the concept that the basic pathologic process consists in an anomaly of secretory function and frequently involves other glandular structures besides the pancreas—notably the respiratory tract, the intestinal tract and the biliary system. The development of fixed organic lesions in the affected organs was found to be variable and to depend to some extent on the time factor. Extrapancreatic lesions were rare and inconspicuous in infants dying in the newborn period, whereas, in patients who had survived the newborn period, involvement of the respiratory tract was constant and changes in other systems were commonly encountered. Variations in the intensity of the pancreatic changes suggested the possibility of a postnatal onset of the process in some cases. Inspissation of abnormally viscid meconium in the small intestine was the sole demonstrable cause of complete intestinal obstruction in four of the five patients dying with meconium ileus in the newborn period. It was shown however that inspissation of meconium as part of the disease process can lead to secondary obliteration and organic atresia of the intestine in utero. Evidence was presented to show that the atresia of the cystic duct frequently encountered in older infants is due to a similar process of secondary obliteration. A detailed study of the pulmonary lesions encountered in 28 patients with respiratory symptoms indicated that the original pathologic process in the lungs is analogous to that in the pancreas and consists in an accumulation of viscid secretion in the air passages. The resulting state of respiratory obstruction is an important component of the disease process which by itself can lead to death. This point was illustrated by a representative case history. The respiratory tract, being, in contrast to the pancreas, accessible to bacterial invaders, usually becomes the seat of secondary infection which is perpetuated in the presence of inadequate drainage from the plugged air passages and leads to progressive inflammatory changes. No evidence for a primary nutritional factor in the genesis of the pulmonary changes was found. The conclusion was reached that nutritional deficiencies play a secondary though clinically important part in the evolution of the disease process.
Prey dynamics affect foraging by a pelagic predator (Stenella longirostris) over a range of spatial and temporal scales

Studies have shown that pelagic predators do not overlap with their prey at small scales. However, we hypothesized that spinner dolphin foraging would be affected by the spatio-temporal dynamics of their prey at both small and large scales. A modified echosounder was used to simultaneously measure the abundance of dolphins and their prey as a function of space and time off three Hawaiian islands. Spinner dolphin abundance closely matched the abundance patterns in the boundary community both horizontally and vertically. As hypothesized, spinner dolphins followed the diel horizontal migration of their prey, rather than feeding offshore the entire night. Spinner dolphins also followed the vertical migrations of their prey and exploited the vertical areas within the boundary layer that had the highest prey density. Cooperative foraging by pairs of dolphins within large groups was evident. The geometric and density characteristics of prey patches containing dolphins indicate that dolphins may alter the characteristics of prey patches through this cooperative foraging. The overlap of Hawaiian spinner dolphins and their prey at many temporal and spatial scales, ranging from several minutes to an entire night and 20 m to several kilometers, indicates that the availability of truly synoptic data may fundamentally alter our conclusions about pelagic predator-prey interactions.