cssi/SciSciGPT-SciSciNet huggingface dataset:
Facile aminolysis of epoxides with diethylaluminum amides

Abstract Treatment of an epoxide with a diethylaluminum amide in dichloromethane at room temperature affords the corresponding β-amino alcohol in good yield.
Theoretical calculations on an acetic acid, 5-methylimidazole, methanol hydrogen bond network: a model charge relay system.

Abstract The CNDO/2 MO SCF method is used to calculate canonical form stabilities, proton potential energy curves, charge redistributions, and hydrogen bond strengths in a model charge relay system. The model system consists of methanol, 5-methylimidazole and acetic acid. The carboxylate group is observed to (i) increase the negative charge on the methanol oxygen, (ii) increase the methanol-imidazole hydrogen bond strength and (iii) reduce the proton transfer energies. Consideration of an extended model system indicates that solvation of the model system further reduces the proton transfer energies. These results are consistant with the proposed role of the buried aspartate group in activating the reactive serine oxygen in the serine proteinase enzymes.
Doublet—quartet transitions in nitric oxide by low-energy variable-angle electron scattering☆

Abstract The electron impact spectrum of nitric oxide between 4 eV and 10 eV energy loss has been studied in detail at impact energies of 25, 35 and 50 eV and a
Optimal cooperative search in fractional cascaded data structures

Fractional cascading is a technique designed to allow efficient sequential search in a graph with catalogs of total sizen. The search consists of locating a key in the catalogs along a path. In this paper we show how to preprocess a variety of fractional cascaded data structures whose underlying graph is a tree so that searching can be done efficiently in parallel. The preprocessing takesO(logn) time withn/logn processors on an EREW PRAM. For a balanced binary tree, cooperative search along root-to-leaf paths can be done inO((logn)/logp) time usingp processors on a CREW PRAM. Both of these time/processor constraints are optimal. The searching in the fractional cascaded data structure can be either explicit, in which the search path is specified before the search starts, or implicit, in which the branching is determined at each node. We apply this technique to a variety of geometric problems, including point location, range search, and segment intersection search.
Fish assemblages of the central Appalachian Moutains: an examination of trophic group abundance in nine West Virginia streams

We used multivariate ordination techniques to examine patterns of trophic group abundance among fish assemblages in nine West Virginia streams. These patterns were examined in relation to habitat and water chemistry gradients. The first two components from a principal components analysis (PCA) explained 71% of the variation in trophic group abundance. The first two axes from a PCA of habitat data accounted for 75% of the total variation. Generalized insectivores and insectivore-piscivores were the predominant trophic groups in stable, pool environments. Benthic insectivores and herbivores-detritivores were most abundant in shallow, temporally variable environments. We attributed the presence of generalized insectivores in deep, pool environments to the effects of a severe drought. The predominance of benthic insectivores in shallow environments was attributed to an abundance of benthic stream fishes and a depauperate catostomid assemblage.
Spare PRELI gene loci: failsafe chromosome insurance?

Background LEA (late embryogenesis abundant) proteins encode conserved N-terminal mitochondrial signal domains and C-terminal (A/TAEKAK) motif repeats, long-presumed to confer cell resistance to stress and death cues. This prompted the hypothesis that LEA proteins are central to mitochondria mechanisms that connect bioenergetics with cell responses to stress and death signaling. In support of this hypothesis, recent studies have demonstrated that mammalian LEA protein PRELI can act as a biochemical hub, which upholds mitochondria energy metabolism, while concomitantly promoting B cell resistance to stress and induced death. Hence, it is important to define in vivo the physiological relevance of PRELI expression. Methods and findings Given the ubiquitous PRELI expression during mouse development, embryo lethality could be anticipated. Thus, conditional gene targeting was engineered by insertion of flanking loxP (flox)/Cre recognition sites on PRELI chromosome 13 (Chr 13) locus to abort its expression in a tissue-specific manner. After obtaining mouse lines with homozygous PRELI floxed alleles (PRELI(f/f)), the animals were crossed with CD19-driven Cre-recombinase transgenic mice to investigate whether PRELI inactivation could affect B-lymphocyte physiology and survival. Mice with homozygous B cell-specific PRELI deletion (CD19-Cre/Chr13 PRELI(-/-)) bred normally and did not show any signs of morbidity. Histopathology and flow cytometry analyses revealed that cell lineage identity, morphology, and viability were indistinguishable between wild type CD19-Cre/Chr13 PRELI(+/+) and CD19-Cre/Chr13 PRELI(-/-) deficient mice. Furthermore, B cell PRELI gene expression seemed unaffected by Chr13 PRELI gene targeting. However, identification of additional PRELI loci in mouse Chr1 and Chr5 provided an explanation for the paradox between LEA-dependent cytoprotection and the seemingly futile consequences of Chr 13 PRELI gene inactivation. Importantly, PRELI expression from spare gene loci appeared ample to surmount Chr 13 PRELI gene deficiency. Conclusions These findings suggest that PRELI is a vital LEA B cell protein with failsafe genetics.
No evidence for increased performance of a specialist psyllid on invasive French broom

Abstract Some invasive plants perform better in their area of introduction than in their native region. This may be a consequence of rapid evolutionary change due to different selection pressures encountered in introduced regions. The Evolution of Increased Competitive Ability hypothesis (EICA) suggests that release from natural enemies results in selection of more vigorous plant genotypes as a result of plants allocating resources away from costly herbivore-resistance traits and toward increased growth. We tested the prediction that introduced plant genotypes of Genista monspessulana (Fabaceae) are less resistant to herbivory by a specialist psyllid, Arytinnis hakani (Hemiptera: Psyllidae) by measuring and comparing A. hakani performance on plants from native (southern France) and introduced (California, U.S.) populations. A. hakani performed equally well on plants from the native and introduced regions; there were no significant differences in psyllid egg and nymphal development, nymphal survival rates, female longevity or fecundity between the test plants. Egg survival rates were significantly higher on native populations, but the difference was minimal. These results provide preliminary evidence that native and introduced G. monspessulana populations are equally resistant to A. hakani and do not support the EICA hypothesis prediction of reduced investment in defense in introduced plant populations. Possible explanations for the lack of effects found in this study include the type of parameters measured and the feeding ecology of the herbivore used to test EICA, and finally, that evolutionary changes in plant defense in introduced G. monspessulana populations may not have occurred.
Cole-Moore superposition and kinetic models for the potassium conductance of nerve fiber membranes.

Abstract Restrictions imposed by “Cole-Moore superposition” on a class of models for the potassium conductance of nerve fiber membranes are studied. The models studied assume that: (1) different potassium transfer sites on the membrane are not coupled; (2) each site is characterized by a set of states |α>, α = 0, …, N , each of energy E α , and degeneracy, r α . (3) The time dependence is described by kinetic equations. It is rigorously shown that: (a) there is superposition if, and only if, in going from one equilibrium state to another, the system passes only through equilibrium states. (b) Condition (a) is satisfied only if: (i) the energy levels are equally spaced, (ii) the state | n > is [ N !/ n !( N - n )!]-fold degenerate, and (iii) only transitions between nearest neighbor levels are allowed.
The appearance of the Cornsweet illusion: Measures of perceived contrast and evenness of brightness

Naval Submarine Medical Research Laboratory, Groton, Connecticut The appearance of the Cornsweet illusion was assessed quantitatively by obtaining measures of the overall perceived contrast of the illusion stimulus and by obtaining magnitude estimations of the apparent homogeneity/evenness of brightness on either side of the luminance discontinuity, including brightness in the neighborhood of the discontinuity. The perceived broad-area contrast of the illusion matched the physical contrast of a comparison step-function stimulus for physical contrasts of 0.2 and below. Ratings of homogeneity of brightness of the illusion tended to be maximal for those same values of physical contrast.
Electrostatic control of charge separation in bacterial photosynthesis.

Electrostatic interaction energies of the electron carriers with their surroundings in a photosynthetic bacterial reaction center are calculated. The calculations are based on the detailed crystal structure of reaction centers from Rhodopseu-domonas viridis, and use an iterative, self-consistent procedure to evaluate the effects of induced dipoles in the protein and the surrounding membrane. To obtain the free energies of radical-pair states, the calculated electrostatic interaction energies are combined with the experimentally measured midpoint redox potentials of the electron carriers and of bacteriochlorophyll (BChl) and bacteriopheophytin (BPh) in vitro. The P+HL- radical-pair, in which an electron has moved from the primary electron donor (P) to a BPh on the 'L' side of the reaction center (HL), is found to lie approx. 2.0 kcal/mol below the lowest excited singlet state (P*), when the radical-pair is formed in the static crystallographic structure. The reorganization energy for the subsequent relaxation of P+HL- is calculated to be 5.0 kcal/mol, so that the relaxed radical-pair lies about 7 kcal/mol below P*. The unrelaxed P+BL- radical-pair, in which the electron acceptor is the accessory BChl located between P and HL, appears to be essentially isoenergetic with P*.P+BM-, in which an electron moves to the BChl on the 'M' side, is calculated to lie about 5.5 kcal/mol above P*. These results have an estimated error range of +/- 2.5 kcal/mol. They are shown to be relatively insensitive to various details of the model, including the charge distribution in P+, the atomic charges used for the amino acid residues, the boundaries of the structural region that is considered microscopically and the treatments of the histidyl ligands of P and of potentially ionizable amino acids. The calculated free energies are consistent with rapid electron transfer from P* to HL by way of BL, and with a much slower electron transfer to the pigments on the M side. Tyrosine M208 appears to play a particularly important role in lowering the energy of P+BL-. Electrostatic interactions with the protein favor localization of the positive charge of P+ on PM, one of the two BChl molecules that make up the electron donor.
Non-contrast-enhanced flow-independent peripheral MR angiography with balanced SSFP.

Flow-independent angiography is a non-contrast-enhanced technique that can generate vessel contrast even with reduced blood flow in the lower extremities. A method is presented for producing these angiograms with magnetization-prepared balanced steady-state free precession (bSSFP). Because bSSFP yields bright fat signal, robust fat suppression is essential for detailed depiction of the vasculature. Therefore, several strategies have been investigated to improve the reliability of fat suppression within short scan times. Phase-sensitive (PS) SSFP can efficiently suppress fat; however, partial volume effects due to fat and water occupying the same voxel can lead to the loss of blood signal. In contrast, alternating repetition time (ATR) SSFP minimizes this loss; however, the level of suppression is compromised by field inhomogeneity. Finally, a new double-acquisition ATR-SSFP technique reduces this sensitivity to off-resonance. In vivo results indicate that the two ATR-based techniques provide more reliable contrast when partial volume effects are significant.
Toxicological evaluation of compounds found in food using rat renal explants.

Abstract A rat kidney expiant system was developed and its respiratory characteristics in the presence and absence of a series of compounds found in food were studied. Cubes taken from the whole kidneys of male Osborne-Mendel rats were incubated under sterile conditions for up to 18 hr. The respiratory activity of these expiants after incubation was measured by determining the amount of 14 CO 7 evolved as a result of the metabolism of [ 14 C]glucose. Changes in membrane permeability as a result of treatment were assessed by measuring the total protein content in the medium. Measurements of respiratory activity showed that the biochemical integrity of the control expiants was well maintained over the test period. Various compounds were tested at a range of concentrations from 0·1 to 1·0 mM. In the initial screen, several of the compounds tested at 1mM—butylated hydroxytoluene (BHT), butylated hydroxy-anisole (BHA), DDT, polychlorinated biphenyl (Aroclor 1254), patulin, zearalenone and cadmium chloride—markedly inhibited respiration; neither ascorbic acid nor caffeine was effective at this concentration. Two of the fat-soluble compounds, DDT and zearalenone, inhibited respiration at concentrations of 0·1 and 0·25 mM concentrations, respectively, while patulin, a water-soluble mycotoxin, did not give significant inhibition at concentrations below 0·5 mM. In some cases, e.g. patulin and BHA, the dose-response curves appeared to be bimodal, with stimulation of respiration occurring at lower concentrations. The two mycotoxins, patulin and zearalenone, and the antioxidant BHA produced losses of cellular protein at concentrations of 1·0, 0·50 and 1·0 mM, respectively, indicating membrane perturbation. Thus, this kidney expiant system responded consistently to a variety of known toxins and can be considered as another in vitro method of determining which compounds show the potential for in vivo toxicity.
Detection of auroral hydrogen Lyman-alpha emission from Uranus

A series of observations of Uranus obtained with the short-wavelength spectrograph of the International Ultraviolet Explorer Observatory in 1982 April and June have revealed unexpectedly strong H Lyman-alpha emission which varied between 430 and 850 rayleighs in observed disk-averaged brightness over the course of these observations. The variability of the emission alone indicates that much of the emission must be produced by charged particle excitation of H in Uranus's upper atmosphere. In addition, comparison of these data with a model for resonant scattering of solar H Lyman-alpha emission indicates that, over a wide range of model conditions, an emission brightness of even 430 rayleighs (which was the lowest observed value) corresponds to an H column density on the order of 10 to the 17th/sq cm in Uranus's upper atmosphere. These data offer the first strong evidence for the presence of aurorae and therefore a magnetic field on Uranus.
Defending the cornea with antibacterial fragments of keratin

In addition to its role in refraction, the cornea forms a barrier between the eye and environmental and infectious insults. Corneal infections are surprisingly rare, suggesting that multiple aspects of the immune system are at play in mediating protection. In this issue of the JCI, Tam et al. describe the unexpected role of a structural protein, cytokeratin 6A, in this process.
Observation of vibrational enhancement using pre-resonant infrared four wave mixing

Abstract A vibrational enhancement of the third order optical susceptibility ( χ (3) ) is found for the CH stretch of hexane using nonparametric infrared four wave mixing. Two tunable infrared beams and one visible laser were focused into hexane with deuterobenzene as an internal standard. The four wave mixing enhancement was measured for different frequencies in the preresonant region using the interference between a coherent Raman process in the deuterobenzene and the vibrationally enhanced nonparametric process from the hexane. The frequency dependence of the nonparametric process matches that expected for vibrational enhancement.
The sequence of precipitation in Cu-2w/0 Be alloys

We present herein a summary of the morphologies and TEM diffraction effects of the several metastable phases observed when a supersaturated Cu-2w/0 Be alloy decomposes at temperatures ranging from 500°C (773 K) to room temperature. These observations are correlated with previously recorded ones and a consistent nomenclature of the metastable phases is given. A metastable equiaxed phase has been found to form prior to the well-known plate-like G.P. zones. Also the sequence of precipitation is recorded as a function of temperature and quenching method. The results are discussed in terms of nucleation theory.
Clinicopathologic Features of Primary Merkel Cell Carcinoma: A Detailed Descriptive Analysis of a Large Contemporary Cohort

BACKGROUNDLittle uniformity exists in the clinical and histologic variables reported with primary Merkel cell carcinoma (MCC).OBJECTIVETo provide a rigorous descriptive analysis of a contemporary cohort and promote the prospective collection of detailed data on MCC for future outcome studies.METHODS
Oxygen diffusion in amphiboles

The kinetics of oxygen isotope self-diffusion in natural samples of hornblende, tremolite, and richterite have been measured. Samples were run under hydrothermal conditions using 18O enriched water. Profiles of 18O(16O + 18O)vs depth into the crystal were obtained using an ion microprobe; the depths of sputtered holes were measured using an optical interferometer. At 1000 bars (100 MPa) water pressure, the activation energies (Q) and pre-exponential factors (D0) for diffusion parallel to c are: D0(cm2/sec) Q (kcal/gm-atom) T (°C) Hornblende 1+20−1 × 10−741 ± 6 650–800 Tremolite 2+30−2× 10−8 39 ± 5 650–800 Richterite 3+5−2 × 10−4 57 ± 2 650–800 The diffusion coefficient (D) for hornblende at 800°C and 1000 bars water pressure measured parallel to the c crystallographic direction is at least ten times greater than that parallel to the a or b directions. An increase in water pressure from 200 to 2000 bars increases D by a factor of 2.7 for diffusion parallel to c at 800°C. The D value for hornblende at 800°C is about 0.01 that for quartz and 0.001 that for anorthite. As a result, closure temperatures for oxygen exchange in natural primary amphiboles are significantly higher than for quartz or feldspars. It is unlikely that amphiboles will exchange oxygen isotopes by diffusion under most crustal conditions.
Attention, ritual glitches, and attentional pull: the president and the queen

This article proposes an analysis of a ritual glitch and resulting “misfire” from the standpoint of a phenomenologically informed anthropology of human interaction. Through articulating a synthesis of some of Husserl‘s insights on attention and affection with concepts and methods developed by anthropologists and other students of human interaction, a case is made for the importance of understanding the social organization of attention in ritual encounters. An analysis of a failed toast during President Obama’s 2011 State Visit to the United Kingdom is used to illustrate how attention is directed toward certain participants, actions, and objects – as opposed to others. Affect-loaded empathic reactions are explained by the protracted temporal unfolding of an action whose successful conclusion – or “repair” - is ostensively and publicly delayed.
Alternative therapy with a recalcitrant fire-setter.

This case report describes treatment of a 10-year-old white boy who had set a major fire in a group home. Various episodes of serious fire-setting continued to occur until one of the authors joined with the boy in constructing a controlled fire. The exercise was repeated three times, with positive results. A three-step intervention approach is described for working with latency-age boys who set fires.
An Alternative Technique for Surgical Management of Poststernotomy Osteomyelitis and Reconstruction of the Sternal Defect

Introduction. Sternal osteomyelitis with or without mediastinal infection is a severe and rare complication of median sternotomy. In this paper, an alternative technique for the reconstruction of sternal defects with the use of bilateral pectoralis major pedicled muscle flaps is presented. Case presentation. A 70-year-old man with the diagnosis of poststernotomy osteomyelitis underwent reconstruction of his sternal defect with the use of bilateral pectoralis major muscle flaps. The patient had an uneventful recovery, and the physical examination revealed a normal range of motion for both upper limbs and sternal stability. Conclusion. The proposed technique incorporates a simple mobilization of the two pectoralis major muscles to be used as flaps to fill the sternal defect without the need for humeral detachment or a second cutaneous incision. Using this technique, a muscular implant is made that seals the dead space, which has no tension due to the presence of a second layer. Postoperative results are excellent, not only regarding infection and functionality but also from an aesthetic point of view.
Psychostimulants, L-type Calcium Channels, Kinases, and Phosphatases

There is growing evidence for the role of voltage-gated L-type Ca2+ channels in mediating aspects of the addictive properties of psychostimulants. L-type Ca2+ channels activate Ca2+ second-messenger pathways that regulate protein phosphorylation and thereby activation of target gene expression. Here the authors will review recent progress in our understanding of L-type Ca2+ channel-activated signal transduction pathways that contribute to molecular neuroadaptations evident following acute and chronic exposures to psychostimulants.
Phosphorylation of Histone H4 Serine 1 during DNA Damage Requires Casein Kinase II in S. cerevisiae

Summary Distinct patterns of posttranslational histone modifications can regulate DNA-templated events such as mitosis, transcription, replication, apoptosis, and DNA damage [1–5], suggesting the presence of a "histone code" in these nuclear processes [6, 7]. Phosphorylation of histone H2A S129 at sites of DNA double-strand breaks (DSBs) has been implicated in damage repair in yeast [8, 9]. Here, we describe another phosphorylation event on serine 1 (S1) of histone H4; this event is also associated with MMS- or phleomycin-induced DSBs but not with UV-induced DNA damage. Chromatin-immunoprecipitation (ChIP) studies of an HO-endonuclease-inducible strain show that S1 phosphorylation is specifically enhanced 20- to 25-fold in nucleosomes proximal to the DSB. In addition, we show that casein kinase II (CK2) can phosphorylate H4 S1 in vitro and that null or temperature-sensitive CK2 yeast mutants are defective for induction of H4 S1 phosphorylation upon DNA damage in vivo. Furthermore, H4 S1 phosphorylation and CK2 play a role in DSB re-joining as indicated by a nonhomologous end-joining (NHEJ) plasmid assay. CK2 has been implicated in regulating a DNA-damage response; our data suggest that histone H4 S1 is one of its physiological substrates. These data suggest that this modification is a part of the DNA-repair histone code.
Biaxial Response of Ovine Spinal Cord Dura Mater

The dura mater performs a major functional role in the stability and mechanical response of the spinal cord complex. Computational techniques investigating the etiology of spinal cord injury require an accurate mechanical description of the dura mater. Previous studies investigating the mechanical response of the dura mater have reported conflicting results regarding the anisotropic stiffness of the dura in the longitudinal and circumferential direction. The aim of this study was to investigate the biaxial response of the dura mater in order to establish the tissue level mechanical behavior under physiological loading scenarios. To this end, square sections of the dura were tested in a custom biaxial setup under a comprehensive uniaxial and biaxial loading protocol. The resultant data were fit via a transversely isotropic continuum model and an anisotropic continuum constitutive model. The transversely isotropic formulation failed to accurately predict the dura mater׳s uniaxial behavior. The anisotropic formulation accurately predicted the uniaxial response in both longitudinal and circumferential directions. Significantly higher stiffness (p<0.0001) was observed in the circumferential direction as compared to the longitudinal direction. Further, the longitudinal direction displayed a significantly lower degree of nonlinearity (p<0.045) and significantly higher degree of collagen fiber dispersion (p<0.032) as compared to the circumferential direction. Results indicate that the dura mater has differential mechanical response in the longitudinal and circumferential directions and future studies should utilize an anisotropic two fiber family continuum model to accurately describe dura mater mechanics.
How are we going to test SOC's on a board?

This abstract discusses how the testing of SOC's on boards can be addressed in the current manufacturing test environment
High Bone Mass as a Marker for Breast Cancer Risk

Postmenopausal women in the highest quartile for metacarpal bone mass were found to have an increased risk of developing breast cancer, after adjusting for age and other variables known to influence breast cancer risk. Although the mechanisms responsible for this relationship have not been identified, postmenopausal bone mass may serve as an indicator of cumulative estrogen exposure.
Tolerating latency through software-controlled prefetching in shared-memory multiprocessors

Abstract The large latency of memory accesses is a major obstacle in obtaining high processor utilization in large-scale shared-memory multiprocessors. Although the provision of coherent caches in many recent machines has alleviated the problem somewhat, cache misses still occur frequently enough that they significantly lower performance. In this paper we evaluate the effectiveness of nonbinding software-controlled prefetching , as proposed in the Stanford DASH multiprocessor, to address this problem. The prefetches are nonbinding in the sense that the prefetched data is brought to a cache close to the processor, but is still available to the cache-coherence protocol to keep it consistent. Prefetching is software-controlled since the program must explicitly issue prefetch instructions. The paper presents results from detailed simulation studies done in the context of the Stanford DASH multiprocessor. Our results show that for applications with regular data access patterns—we evaluate a particle-based simulator used in aeronautics and an LU-decomposition application—prefetching can be very effective. It was easy to augment the applications to do prefetching and their performance was increased by 100–150% when we prefetched directly into the processor's cache. However, for applications with complex data usage patterns, prefetching was less successful. After much effort, the performance of a distributed-time logic simulation application that made extensive use of pointers and linked lists could be increased by only 30%. The paper also evaluates the effects of various hardware optimizations such as separate prefetch issue buffers, prefetching with exclusive ownership, lockup-free caches, and weaker memory consistency models on the performance of prefetching.
Retrograde lymphatic spread and ischemia of the forearm and hand—rare complications of carcinoma of the breast

A case of ischemia of the forearm and hand with resulting necrosis three years following simple mastectomy and radiation therapy for breast carcinoma is reported. Histologic sections of the mid-forearm amputation specimen showed extensive lymphatic involvement by tumor. The latter process is judged to have been one of retrograde lymphatic extension. Cancer 40:371–375, 1977.
The merging of the US and European polar environmental satellite programs and its impact on NOAA

The National Environmental Satellite, Data, and Information Service (NESDIS), part of the National Oceanic and Atmospheric Administration (NOAA) is responsible for the establishment and administration of funding for civil operational environmental satellite systems. As part of its planning to transition to a fully integrated international satellite system, NOAA entered into an agreement with the European Organization for the Exploitation of Meteorological Studies (EUMETSAT) for participation in Initial Joint Polar System (IJPS). In the IJPS Agreement, NOAA and EUMETSAT agree to operate their polar-orbiting satellites in a manner beneficial to both parties, as well as the world's meteorological community. The IJPS system allows NOAA to process and distribute the EUMETSAT satellite information as the NOAA morning operational satellite
Mechanism of hemodynamic improvement by dual-chamber pacing for severe left ventricular dysfunction: An acute Doppler and catheterization hemodynamic study

Objectives.This study was undertaken to determine the mechanism by which improvement in hemodynamic variables may occur with dual-chamber pacing in patients with severe left ventricular dysfunction. Background.Dual-chamber pacing has recently been proposed as a therapeutic alternative for the relief of symptoms in patients with dilated cardiomyopathy. Methods.Fifteen patients with severe left ventricular systolic dysfunction were studied acutely during atrioventricular (AV) sequential pacing at various AV intervals (60, 100, 120, 140, 180 and 240 ms) with use of combined Doppler velocity curves and pressures obtained by high fidelity manometer-tipped catheters and thermodilution cardiac output. Results.Neither cardiac output nor mean left atrial pressure was significantly different when hemodynamic variables in the baseline state were compared with those during AV sequential pacing at the various AV intervals in all patients. The patients were classified into two groups. In group I (eight patients with PR intervals >200 ms on the rest 12-lead electrocardiogram), cardiac output was significantly increased when AV sequential pacing at the optimal AV interval to output was compared with that at the baseline state (3.0 ± 1.0 vs. 3.9 ± 0.43 liters/min, p ≈ 0.005) because timing of mechanical atrial and ventricular synchrony was optimized. In addition, left ventricular end-diastolic pressure and duration of diastolic filling were increased, and diastolic mitral regurgitation was abolished. In group II (seven patients who had normal AV conduction at rest), cardiac output during AV pacing decreased from the baseline value withcut change in the diastolic filling period. Conclusions.Dual-chamber pacing any improve acute hemodynamic variables in selecetd patients with dilated cardiomyopathy, mainly by optimization of the timing of mechanical atrial and ventricular synchrony. Reestablishment of the optimal diastolic also contribute to hemodynamic improvement.
Preparation of polymer crystal nuclei

Preparation de suspensions de cristaux de polymeres: refroidissement rapide d'une solution dans le toluene de PEO puis chauffage a temperature ambiante
Computer science education for students training to be secondary teachers

This paper reports on some efforts to provide computer science training for potential teachers in the secondary schools. For those who wish to teach computing concepts, a program consisting of six courses (18 semester hours) of computer science that includes (1) computing concepts studied in the context of both high-level and assembly languages, (2) an exposure to the continuum of applications of computers to education and (3) pertinent electives relative to the students major discipline is outlined. Included are discussions of some relevant issues, rationale for directions taken and specific details about the program.
On Why Corporate Collateral is Necessary for Efficient Stock Markets

Firms issue securities to investors, and nontraded contracts to providers of some non nancial inputs. Nontraded contracts have missing markets a form of externality. This research shows that the stock markets cannot be informationally e cient unless rms hold adequate collateral (riskless capital, e.g., cash, T-bills). Key implications include: i) collateral is required to optimally complete the missing markets and preserve rational expectations, ii) changes in balance sheet collateral a ect stock prices, and iii) collateral is required to maximize the combined welfare of the investors ( Wall Street ) and those transacting from outside the securities markets ( Main Street ).
Lack of association of pleural effusion with chronic pulmonary arterial and right atrial hypertension

Right atrial hypertension has been considered to have a major physiologic influence on the formation of translative pleural effusions. Since pleural fluid is thought to be cleared primarily by the parietal pleural lymphatic vessels that empty into the systemic veins, systemic venous hypertension secondary to right atrial hypertension should decrease the lymphatic drainage of the pleural space. We retrospectively studied nine patients and prospectively studied 18 patients with long-term right atrial or pulmonary arterial hypertension (or both). All patients had stable respiratory symptoms, and none had a significantly elevated pulmonary arterial wedge pressure. Our purpose was to determine the relationship of right atrial and pulmonary arterial hypertension to the development of transudative pleural effusions. Posteroanterior and bilateral decubitus chest roentgenograms and ultrasound were used to detect pleural effusions. Pleural effusions were not identified in any of the 27 patients, even in four patients with right atrial pressures greater than 20 mm Hg. We conclude that chronic elevation of right atrial pressure or pulmonary arterial pressure (or both) alone is not a cause of pleural effusion. In contrast, elevation of left atrial and pulmonary arterial wedge pressures is associated with the formation of transudative pleural effusions in man. Thus, if pleural effusions are detected in patients who have cor pulmonale, a search should be made for coexisting left heart failure or a primary cause of pleural inflammation, such as pulmonary emboli or infection.
Preparation of Nucleic Acid Functionalized Carbon Nanotube Arrays

A vertically aligned carbon nanotube (CNT) array is fabricated as a nanoelectrode platform for biosensor development. Prior to chemical functionalization, metal catalyst particles at the ends of CNT are removed and the closed ends are opened. We find that the oxidative treatment for generating the chemical functional groups at the opened ends of the CNT compromise the mechanical stability of the nanotubes, often leading to total collapse of the aligned CNTs. To solve this problem, we have developed a new approach for filling the gaps between CNTs with a spin-on glass (SOG). Results from the coupling of nucleic acids to the CNT arrays suggest that the SOG enhances the reactivity by providing structural support to the CNTs. The SOG also covers the length of the sidewalls of CNTs, leading to a less hydrophobic interface and thus may aid in improving the chemical reactivity.
A comparison of different AGV dispatching rules in an automated container terminal

Booming world trade, scarcity of land for yard expansion in many ports, and deployment of new massive megaships have magnified the need for finding better ways of performing container terminal operations. Automated Container Terminals (ACTs) using Automated Guided Vehicles (AGVs), with high operation efficiency and requiring less land, can thus become potential candidates for meeting future demand for higher capacity. However, the operation performance of such ACTs also depends on the AGV dispatching rules. In this paper, the performance of four different heuristic AGV dispatching rules in a container terminal operation is investigated. These dispatching rules are popular and easy to be implemented in the field of existing manufacturing systems. Simulations are used to perform terminal operations using those rules. The results show that the minimum yard crane queue size rule can achieve the best throughput performance.
Analytical solutions for flow in porous media with multicomponent cation exchange reactions

Multicomponent cation exchange reactions have important applications in groundwater remediation, disposal of nuclear wastes as well as enhanced oil recovery. The hyperbolic theory of conservation laws can be used to explain the nature of displacements observed during flow with cation exchange reactions between flowing aqueous phase and stationary solid phase. Analytical solutions have been developed to predict the effluent profiles for a particular case of heterovalent cations (Na+, Ca2+ and Mg2+) and an anion (Cl−) for any combination of constant injection and constant initial composition using this theory. We assume local equilibrium, neglect dispersion and model the displacement as a Riemann problem using mass action laws, the charge conservation equation and the cation exchange capacity equation. The theoretical predictions have been compared with experimental data available at two scales—the laboratory scale and the field scale. The theory agrees well with the experimental data at both scales. Analytical theory predictions show good agreement with numerical model, developed using finite differences.
Frontonasal Malformation and Cloacal Exstrophy: A Previously Unreported Association.

We report on a child with frontonasal malformation (FNM) and cloacal exstrophy, a combination of findings that have not been reported previously. In FNM and cloacal exstrophy, associated malformations are rare. FNM and cloacal exstrophy both represent abnormalities of the development of the midline field ; this combination of anomalies in this patient suggests an impairment of caudal and cranial midline development during blastogenesis.
Characterization and Search of Construction Inspection Plan Spaces Developed Using a Component-Based Planning Approach

Formal construction inspection planning is needed to help reduce the incidence of overlooked or inefficient inspections, and to help realize the potential of emerging sensing technologies. Prior publications by the authors have presented requirements for such an approach and a component-based inspection planning implementation as an approach in addressing some of the requirements towards formal construction inspection planning. Implementation of such a component-based approach for typical construction examples, however, leads to the generation of large, rugged search spaces. This paper first describes the characteristics of search spaces that are generated using a component-based approach to illustrate which search mechanisms are appropriate to explore these search spaces. The paper then describes a set of search algorithms and heuristics that were investigated and evaluated for searching construction inspection plans. Specific discussions on how these algorithms performed in searching within inspection planning spaces are provided based on experiments conducted using a testbed characterizing a construction site and a building performance monitoring decision-making example.
Active learning? not with my syllabus!

We describe an approach to teaching probability that minimizes the amount of class time spent on the topic while also providing a meaningful (dice-rolling) activity to get students engaged. The activity, which has a surprising outcome, illustrates the basic ideas of informal probability and how probability is used in statistical inference.
Ellesmerian(?) and Brookian deformation in the Franklin Mountains, northeastern Brooks Range, Alaska, and its bearing on the origin of the Canada Basin

Structural analysis of deformed rocks in the Franklin Mountains, northeastern Alaska, indicates that (1) pre-Carboniferous rocks were transported southeastward during mid-Devonian (Ellesmerian.) thrusting, (2) Cretaceous and older rocks were transported northward during Mesozoic-Cenozoic Brookian thrusting, and (3) the pre-Carboniferous rocks were strongly involved in the Brookian deformation. The strong involvement of these rocks in Brookian structures suggests that the magnitude of northward thrusting during Brookian tectonism is virtually uniform from west to east along the axis of the Brooks Range fold and thrust belt. In addition, the newly recognized southern vergence of pre-Carboniferous structures is comparable with that of coeval structures exposed in Arctic Canada to the east. These data are not easily reconciled with the orocline model for the origin of the Canada Basin but are consistent with left-lateral transport on a north-south-striking transform fault along the Canadian Arctic islands. 19 references.
Visually optimal DCT quantization matrices for individual images

A custom quantization matrix tailored to a particular image is designed by an image-dependent perceptual method incorporating solutions to the problems of luminance and contrast masking, error pooling and quality selectability. >
Large-Scale Sunyaev-Zel'dovich Effect: Measuring Statistical Properties with Multifrequency Maps

We study the prospects for extracting detailed statistical properties of the Sunyaev-Zel'dovich (SZ) effect associated with large scale structure using upcoming multifrequency CMB experiments. The greatest obstacle to detecting the large-angle signal is the confusion noise provided by the primary anisotropies themselves, and to a lesser degree galactic and extragalactic foregrounds. We employ multifrequency subtraction techniques and the latest foregrounds models to determine the detection threshold for the Boomerang, MAP (several microK) and Planck CMB (sub microK) experiments. Calibrating a simplified biased-tracer model of the gas pressure off recent hydrodynamic simulations, we estimate the SZ power spectrum, skewness and bispectrum through analytic scalings and N-body simulations of the dark matter. We show that the Planck satellite should be able to measure the SZ effect with sufficient precision to determine its power spectrum and higher order correlations, e.g. the skewness and bispectrum. Planck should also be able to detect the cross correlation between the SZ and gravitational lensing effect in the CMB. Detection of these effects will help determine the properties of the as yet undetected gas, including the manner in which the gas pressure traces the dark matter.
Numerical simulation of the scavenging rates of ice crystals of various microphysical characteristics

Numerical models of trajectories of small aerosol spheres relative to oblate spheroids were used to determine ice crystal scavenging efficiencies. The models included the effects of aerodynamic flow about the ice particle, gravity, aerosol particle inertia and drag and electrostatic effects. Two electric configurations of the ice particle were investigated in detail. The first applied a net charge to the ice particle, of magnitude equal to the mean thunderstorm charge distribution, while the second applied a charge distribution, with no net charge, to the ice particle to model the electric multipole charge distribution. The results show that growing ice crystals with electric multipoles are better scavengers than single ice crystals with net thunderstorm charges, especially in the Greenfield gap (0.1 to 1.0 μm), and that larger single crystals are better scavengers than smaller single crystals. The results also show that the low density ice crystals are more effective scavengers with net charges than they are with charge distribution.
SNR measurement based on linearity test for ADC BIST

Linearity and spectral performance test contributes most cost of ADC test. This paper presents a new method for testing an ADC's SNR from its linearity test data. The method does not require additional data acquisition or accurate sinusoidal stimulus. Data collected for linearity test is used to compute the input noise power and test ADC's SNR. Both simulation and experimental results show that the proposed method can estimate SNR value accurately.
Effects of Race, Gender, Perceived Similarity, and Contact on Mentor Relationships

Abstract This study examined the effects of similarity, both actual (race and gender) and perceived, and amount of contact between mentor and protege on the quality of mentor relationships. Mentor relationship quality was measured by liking, satisfaction, intended retention, and degree of psychosocial and instrumental functions experienced by the protege. The participants were 104 summer intern proteges and their volunteer staff mentors employed at a large West coast media organization. Proteges were randomly assigned to one of two types of mentor pairings—same and different race mentors. Results indicate that liking, satisfaction, and contact with mentor were higher when proteges’ perceived themselves to be more similar to their mentors. Actual race pairing was related to proteges’ perceptions of the amount of career support and to mentors’ liking of proteges.
Lactic acid production using waste generated from sweet potato processing

Summary Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material with significant residual carbohydrate content. The purpose of this study was to evaluate the potential of waste generated from sweet potato processing material to support the growth of lactic acid bacteria and the production of lactic acid. The waste was comprised of 16.5% solids consisting of 18.5% ash, 4.4% protein, 20.5% simple sugars and 19% soluble starch. Following a screening of three lactic acid bacteria strains, Lactobacillus rhamnosus was deemed the best candidate for lactic acid production. The potential of various dilutions of the enzyme-hydrolysed waste, with and without pH control, as a fermentation substrate was evaluated. Lactic acid production was highest in hydrolysed waste (without dilution) at pH set point 5.0, yielding 10 g L−1 in 72 h. Thus, lactic acid, a valuable organic compound, can be generated from sweet potato waste.