cssi/SciSciGPT-SciSciNet huggingface dataset:
Formation of a manganese alkyl complex as an intermediate in the ring-opening hydroformylation of α-cyclopropylstyrene by HMn(CO)5

Abstract The reaction of α-clopropylstyrene (CPS) with HMn(CO)5 can result in either hydrogenation or hydroformylation. The hydrogenation occurs by a previously established pathway involving sequential hydrogen atom transfers from the metal hydride to the organic substrate, and is the predominant reaction observed with samples of HMn(CO)5 that have been thoroughly dried and purified using P2O5. With samples of HMn(CO)5 that have been not been treated with P2O5, the reaction that occurs with CPS is ring-opening hydroformylation, leading to the isolation of Mn2(CO)9(η1-HCOCH2CH2CHC(Ph)CH3). The detailed procedures for preparation and handling of HMn(CO)5 that are reported in this paper enable the hydroformylation reaction to be reproducible observed as the predominant reaction. An induction period of a few hours is typically observed in the hydroformylation, but addition of Mn2(CO)9(η1-tolualdehyde) eliminates the induction period. The hydroformylation reaction is inhibited by CO (1 atm). The manganese alkyl complex (CO)5MnCH2CH2CHC(Ph)CH3 is an intermediate in the hydroformylation. The details of the mechanism of formation of this alkyl complex from CPS and HMn(CO)s are not completely understood, but several mechanistic possibilities are considered.
Enriching Our Understanding of the Effects of Childhood Poverty: Lessons From Bangladesh

A sobering fact to consider: the likelihood that any of us will achieve a state of sustained well-being as adults is bounded quite early in life by factors entirely beyond our control. Where one is born, when, and to whom establishes guardrails for a path of development to which merit or effort contributes but modestly. Of all the disadvantageous contingencies to which one might be exposed in early life, poverty is among the most punishing. Its effects are known to be pervasive, long lasting, and protean in their manifestations.1,2 Those who start out life poor grow less well,3 are subject to more frequent and grave episodes of illness,4 attain lesser levels of academic advancement, experience cognitive challenges unlike their more fortunate counterparts,5 earn less money,6 acquire fewer assets, develop adult-onset chronic illnesses at higher rates,7 marry less often, and die earlier.8 Despite voluminous documentation of these associations, there is yet much that remains to be explained about the pathways through which poverty exerts these pernicious influences and, in particular, its impact on cognitive development. In this issue of Pediatrics , Hamadani and colleagues contribute to our understanding of this dynamic through their study of a cohort of children in rural Bangladesh.9 The authors enrolled 2853 singleton children born between May 2002 and December 2003 and collected data on their parents, their growth parameters over the succeeding 64 months, the material resources available to their families, and information about the richness of the environments in which they were … Address correspondence to Andrew D. Racine, MD, PhD, Montefiore Medical Center, 111 East 210th St, Bronx, NY 10467. E-mail: aracine{at}montefiore.org
Toward a theory of Pollard's rho method

Abstract Pollard's “rho” method for integer factorization iterates a simple polynomial map and produces a nontrivial divisor of n when two such iterates agree modulo this divisor. Experience and heuristic arguments suggest that a prime divisor p should be detected in O( p ) steps, but this has never been proved. Indeed, nothing seems to be have been rigorously proved about the probability of success that would improve the obvious lower bound of 1 p . This paper shows that for fixed k , this probability is at least ( 2 k ) p + O(p −3 2 ) as p → ∞. This leads to an Ω( log 2 p) p estimate of the success probability.
Surface smoothing and partial spatial derivatives computation using a regressive discrete Fourier series

Abstract The smoothing of surfaces which can be described as scalar functions of a two-dimensional domain is classical in image processing. Smoothing techniques can be used in experimental modal analysis applications to smooth spatially dense measured operating shapes. When transformation filtering techniques are used, a mathematical model of the smoothed surface is obtained. The mathematical model of the out-of-plane displacement operating shape surface can be used to calculate in-plane angular displacements, thus increasing by threefold the number of degrees-of-freedom obtained from the experimental measurements. In this paper, a surface smoothing method consisting of estimating by least-squares the coefficients of a two-dimensional discrete Fourier series with arbitrary period and arbitrary frequency resolution is presented. It is shown that the proposed method called Regressive Discrete Fourier Series (RDFS) minimises the leakage problem and can be used with non-equally-spaced and non-rectangular-domain data. The RDFS method is compared to a more classical approach consisting of using the two-dimensional discrete Fourier transform (DFT). With the Fourier series model it is straightforward to calculate partial derivatives. Numerical results are shown to illustrate the proposed method and to compare it to the two-dimensional DFT method, which was enhanced with spline padding to reduce leakage.
A Self-Consistent Approach to the Elastic Stiffness of Short-Fiber Composites

The self-consistent approach originally proposed by Hill has been adopted to derive the effective elastic stiffness constants of unidirectional short-fiber composites. The short-fibers are modeled as ellipsoidal inclu sions uniformly distributed in the matrix and the transverse isotropy of the composite has been taken into account. The method of analysis is valid for multi-component systems and hence, applicable to hybrid composites. Comparisons of this analysis with existing theories are made for binary composites.
Integration of Polymer Self-Assembly for Lithographic Application

Directed polymer self-assembly which combines lithographically defined substrates and self-assembled polymers has been considered as a potential candidate to extend conventional patterning techniques. In the past few years, successful demonstration of directed self-assembly of block copolymer shows that this method can afford sub-lithographic resolution or enhances dimensional control. However, integration of polymer self-assembly into standard lithographic processes remains a challenge and requires new materials. In this paper, we demonstrate robust and thermally crosslinked underlayer materials which control the orientation of block copolymer assemblies and are compatible with standard lithographic processes. These new materials allow simple integration of perpendicularly oriented polystyrene-b- polymethylmethacrylate (PS-b-PMMA) domains into standard manufacturing processes.
Automatic detection of pulsed radio frequency (RF) targets using sparse representations in undercomplete learned dictionaries

Automatic classification of transitory or pulsed radio frequency (RF) signals is of particular interest in persistent surveillance and remote sensing applications. Such transients are often acquired in noisy, cluttered environments, and may be characterized by complex or unknown analytical models. Conventional representations using orthogonal bases, e.g., Short Time Fourier and Wavelet Transforms, can be suboptimal for classification of transients, as they provide a rigid tiling of the time-frequency space, and are not specifically designed for a particular target signal. They do not usually lead to sparse decompositions, and require separate feature selection algorithms, creating additional computational overhead. We propose a fast, adaptive classification approach based on non-analytical dictionaries learned from data. Our goal is to detect chirped pulses from a model target emitter in poor signal-to-noise and varying levels of simulated background clutter conditions. This paper builds on our previous RF classification work, and extends it to more complex target and background scenarios. We use a Hebbian rule to learn discriminative RF dictionaries directly from data, without relying on analytical constraints or additional knowledge about the signal characteristics. A pursuit search is used over the learned dictionaries to generate sparse classification features in order to identify time windows containing a target pulse. We demonstrate that learned dictionary techniques are highly suitable for pulsed RF analysis and present results with varying background clutter and noise levels. The target detection decision is obtained in almost real-time via a parallel, vectorized implementation.
Polymerization of two unsaturated fatty acid esters in Langmuir-Blodgett films as studied by IR spectroscopy☆

Abstract The two isomers octadecyl fumaric acid and octadecyl maleic acid (C 18 H 37 OCOCHCHCOOH) have been synthesized, and Langmuir-Blodgett (LB) films of their cadmium salts have been prepared on silver, aluminum and thallium bromoiodide substrates. The orientation of the molecules relative to the substrate surface and the lateral packing of the chains in the unit cell were studied by means of transmission and grazing incidence reflection IR spectroscopy. Using the latter technique, polymerization of these films by both UV radiation and thermal heating was followed as a function of exposure time. By comparison with films polymerized on the water surface of a Langmuir trough, it was concluded that all three polymerization processes produce films with a similar molecular structure in the head group region, but with differences in orientation of the aliphatic chains. Interestingly, on polymerization on the water surface, the fumarate undergoes an expansion at constant surface pressure whereas the maleate contracts. A mixture of fumarate and maleate in the ratio of 1:3, however, forms a solution and preserves its area on polymerization, a critical feature required for the fabrication of crack-free LB films polymerized on solid substrates.
Hollow-fiber membrane bioreactors using immobilized E. coli for protein synthesis.

Actively growing Escherichia coli C600(pBR322), immobilized within the macroporous matrix of asymmetric-wall hollow-fiber membranes, has been propagated to extremely high densities, typically more than 10 12 cells/mL of accessible void volume, in some regions cells accounting for nearly 100% of the available macrovoid volume forming a tissue-like mass. Production rates of β-lactamase, an enzyme used as an indicator of the culture's biosynthetic potential, remained at high and relatively stable levels for more than three weeks of continuous operation, and effluent supernatant enzyme activities attained 25% of the accumulated level measured in a 24-h shaker-flask culture. Based on the accessible void volume within the fiber wall, the β-lactamase productivity was independent of the specific asymmetric membrane used. On a per cell basis, however, cells cultured using hollow-fiber membranes were only 10% as productive as those in the shaker-flask culture, possibly due to the high packing density or culture aging. By contrast, the hollow-fiber bioreactor was 100 times more productive than the shaker-flask culture on a reactor-volume basis, primarily as a consequence of the high cell densities. Reactor productivity was dependent on the number of cells in the reactor, suggesting that reactor performance was kinetically controlled and not mass transport limited Immobilisation d'E.c. C600(pBR322) utilise comme microorganisme modele sur des membranes asymetriques de fibres creuses, et etude de la production de β-lactamase. La production de cet indicateur du potentiel biosynthetique de la culture, reste a un taux eleve et relativement stable pendant plus de 3 semaines de processus continu. Ce bioreacteur se revele 100 fois plus productif que la culture en flacon agite, du fait en particulier de la forte densite cellulaire
Theory of Large-Scale Plastic Deformation in Amorphous Materials: A Progress Report

The goal of recent shear-transformation-zone (STZ) theories has been to construct a phenomenological description of amorphous plasticity that is based on physical principles and molecular models, and yet is simple enough to be useful in predicting the performance of real materials. In reporting progress toward this goal, I focus on the dynamic role played by the effective disorder temperature (a generalization of the free-volume) in controlling relaxation rates and predicting shear-banding instabilities.
Effects of an invasive cattail species (Typha×glauca) on sediment nitrogen and microbial community composition in a freshwater wetland

Sediments from Cheboygan Marsh, a coastal freshwater wetland on Lake Huron that has been invaded by an emergent exotic plant, Typha × glauca , were examined to assess the effects of invasion on wetland nutrient levels and sediment microbial communities. Comparison of invaded and uninvaded zones of the marsh indicated that the invaded zone showed significantly lower plant diversity, as well as significantly higher aboveground plant biomass and soil organic matter. The sediments in the invaded zone also showed dramatically higher concentrations of soluble nutrients, including greater than 10-fold higher soluble ammonium, nitrate, and phosphate, which suggests that Typha × glauca invasion may be impacting the wetland's ability to remove nutrients. Terminal restriction fragment length polymorphism analyses revealed significant differences in the composition of total bacterial communities (based on 16S-rRNA genes) and denitrifier communities (based on nirS genes) between invaded and uninvaded zones. This shift in denitrifiers in the sediments may be ecologically significant due to the critical role that denitrifying bacteria play in removal of nitrogen by wetlands.
Depression and mortality in end-stage renal disease

End-stage renal disease is growing in prevalence and incidence. With technical advancements, patients are living longer on hemodialysis. Depression is the most prevalent comorbid psychiatric condition, estimated at about 25% of end-stage renal disease samples. The identification and assessment of depression are confounded by the overlap between depression symptomatology and uremia. Several recent studies have employed time-varying models and identified a significant association between depression and mortality. Due to the high prevalence of depression and the potential impact on survival, well-constructed investigations are warranted.
Outcomes of melanoma in recipients of solid organ transplant.

Background There is concern that the immunologic tumor malignant melanoma (MM) may have worse outcomes in immunosuppressed hosts than in the general population. Objective We sought to describe outcomes of MM in immunosuppressed solid organ transplant recipients and compare them with the general population. Methods We conducted a retrospective review of medical charts and pathology slides of cases of MM and solid organ transplantation between 1978 and 2007, with comparison of outcomes. Results In all, 48 MMs were identified in 43 transplant recipients. No patient with MM before transplant receipt had melanoma recurrence, subsequent metastasis, or death caused by melanoma. Of patients with MM diagnosed after transplantation, metastases developed in 3 patients, and two patients died of melanoma. Limitations Retrospective review and low number of cases are limitations. Conclusions Outcomes of MM in immunosuppressed transplant recipients appeared similar to those in prognostically matched nonimmunosuppressed hosts. The small number of cases limited statistical comparisons.
Molecular cloning and analysis of fructokinase expression in tomato (Lycopersicon esculentum Mill.)

Abstract A cDNA encoding a tomato (Lycopersicon esculentum Mill.) fructokinase (FK, ATP:fructose-6-phosphotransferase, E.C. 2.7.1.4) was cloned by screening a cDNA library made from young cherry tomato fruit with a potato FK cDNA. The 1243 bp cDNA contains a 981 bp open reading frame encoding a 327 amino acid protein with a calculated molecular mass of 34 819 Da and an isoelectric point (pI) of 7.27. Southern-blot analysis suggests that in tomato, this FK is encoded by a single gene. The expression is controlled at the transcriptional level with mRNA primarily expressed in young fruit and mature root tissue. The FK protein is widely distributed in the plant except in leaf tissue. Enzyme activity is greatest in the developing fruits, but substantial activity is present in mature petioles and stems too. Protein and/or mRNA stability may be a factor in determining enzyme activity levels, however, differential expression of multiple genes may also explain differences between FK protein/FK activity levels and FK mRNA levels.
Effect of isoniazid on cerebrospinal fluid and plasma GABA levels in Huntington's disease.

Abstract During a double-blind placebo controlled trial, γ-aminobutyric acid (GABA) was measured in cerebrospinal fluid (CSF) and plasma obtained from patients with Huntington's Disease prior to the start of the trial, at the end of the placebo period and following treatment with isoniazid. The results showed that the GABA concentrations in CSF tripled following treatment with isoniazid although no significant change occurred in plasma GABA levels. This finding in humans indirectly confirms reports of a similar increase of brain GABA content in experimental animals following isoniazid treatment and provides additional evidence that CSF GABA measurements reflect brain GABA activity.
Analytic Review: Pituitary Tumor Apoplexy: A Review:

Pituitary tumor apoplexy is an uncommon syndrome resulting often spontaneously from hemorrhage or infarction of a pre-existing pituitary adenoma. As the primary event involves the adenoma, the synd...
Essential role of lysyl oxidases in notochord development

Recent studies reveal a critical role for copper in the development of the zebrafish notochord, suggesting that specific cuproenzymes are required for the structural integrity of the notochord sheath. We now demonstrate that β-aminopropionitrile, a known inhibitor of the copper-dependent lysyl oxidases, causes notochord distortion in the zebrafish embryo identical to that seen in copper deficiency. Characterization of the zebrafish lysyl oxidase genes reveals eight unique sequences, several of which are expressed in the developing notochord. Specific gene knockdown demonstrates that loss of loxl1 results in notochord distortion, and that loxl1 and loxl5b have overlapping roles in notochord formation. Interestingly, while notochord abnormalities are not observed following partial knockdown of loxl1 or loxl5b alone, in each case this markedly sensitizes developing embryos to notochord distortion if copper availability is diminished. Likewise, partial knockdown of the lysyl oxidase substrate col2a1 results in notochord distortion when combined with reduced copper availability or partial knockdown of loxl1 or loxl5b. These data reveal a complex interplay of gene expression and nutrient availability critical to notochord development. They also provide insight into specific genetic and nutritional factors that may play a role in the pathogenesis of structural birth defects of the axial skeleton.
Optimal passive dynamics for torque/force control

For robotic manipulation tasks in uncertain environments, good force control can provide significant benefits. The design of force or torque controlled actuators typically revolves around developing the best possible software control strategy. However, the passive dynamics of the mechanical system, including inertia, stiffness, damping and torque limits, often impose performance limitations that cannot be overcome with software control. Discussions about the passive dynamics are often imprecise, lacking comprehensive details about the physical limitations. In this paper, we develop relationships between an actuator's passive dynamics and the resulting performance, for the purpose of better understanding how to tune the passive dynamics for a force control task. We present two distinct scenarios for the actuator system and calculate the required input to produce a desired output. These exact solutions provide a basis for understanding how the parameters of the mechanical system affect the overall system's bandwidth limit. Our model does not include active control; we computed the optimal input to the system to produce the required torque at the load with zero error. This is important so that our results only reflect the physical system's performance.
Mechanisms and implications of endothelial dysfunction in congestive heart failure.

The pathogenesis of heart failure is determined by the ventricular and vascular responses to myocellular injury. Experimental and clinical studies suggest that the vascular endothelium may play an important role in modulating progression of ventricular and vascular remodeling in heart failure. Endot
Thermotropic Liquid Crystalline Character and Vesicular Properties of Some Functionalized Long-Chain Di-n-dodecyl Quaternary Ammonium Salts

Abstract In several reports it has been shown that amphiphilic molecules, including phospholipids, which aggregate in solution to form micelles, vesicles or liposomes also exhibit thermotropic liquid crystalline phases. In conjunction with our recent work on the synthesis and characterization of vesicle-forming monomeric and polymerized allyl and diallyl di-n-alkyl quarternary ammonium salts, a series of analogously functionalized derivatives has been prepared. Di-n-dodecyldimethyl quarternary ammonium bromide was employed as the parent compound. The new quarternary ammonium salts were formed by replacing one or both of the methyl groups in the parent compound by groups such as—CH2—CH=CH2,—CH2CH2OH,—CH2COOH,—CH2CH2COOH, or—CH2CH2CH2CN. The existence of liquid crystalline phases in these quarternaries was established by optical microscopy while transition temperatures as well as thermodynamic parameters were determined by DSC. Some of these compounds when dispersed in water and sonicated ultimately formed ...
Using Facebook to Facilitate Course-Related Discussion Between Students and Faculty Members

Objectives. To use Facebook to facilitate online discussion of the content of a Comprehensive Disease Management course and to evaluate student use and perceptions of this exercise.Design. A Facebook page was created and coordinators encouraged students to “like” the page and to post and view study tips, links, or questions. At the end of the course, students’ use and perceptions were evaluated using an anonymous survey tool.Assessment. At the end of week 1, there were 81 followers, 5 wall posts, and 474 visits to the course Facebook page. At peak use, the page had 117 followers, 18 wall posts, and 1,326 visits. One hundred nineteen students (97% of the class) completed the survey tool. Twenty-six percent of students contributed posts compared to 11% who posted on the course discussion board on Blackboard. Students were more likely to post and be exposed to posts on Facebook than on Blackboard. Students found Facebook helpful and 57% said they would miss Facebook if use was not continued in subsequent cou...
SYNGAMY AND PLASMODIUM FORMATION IN THE MYXOGASTRES

IT IS GENERALLY acknowledged that the plasmodium of the Myxogastres is initiated by the fusion of motile gametes. Since Wilson and Ross (1955) demonstrated that meiosis in the Myxogastres occurs just before spore formation in the maturing sporangium, there is no doubt that the spores and the resulting swarm cells and myxamoebae are haploid. The positions of syngamy, karyogamy and plasmodium formation in the life cycle, however, are still unsettled. Reports of previous investigators on these aspects of the life cycle have presented conflicting evidence and no interpretation made up to the present has been wholly accepted. Martin (1940), in his review of the Myxomycetes, states that even though it is generally agreed that the swarm cells and myxamoebae are haploid, the position of nuclear fusion in the life cycle is in doubt, and that it is difficult to present a generalized account of the nuclear cycle of the Myxomycetes. Skupienski (1920, 1926) and Schiinemann (1930) believed that two to many myxamoebae fused to form a plasmodium, but that karyogamy was delayed until later in the development of the plasmodium. Von Stosch (1935), however, reported that syngamy was between flagellate swarm cells, not between myxamoebae. He stated that Didymium squamulosum, D. xanthopus, and Physarum cinereum were apogamous, since he had not observed fusion of swarm cells in these species. M. Wilson and Cadman (1928) described the fusion of swarm cells in Reticularia Lycoperdon and noted that karyogamy followed immediately after plasmogamy. They also found that several swarm cells would fuse with a zygote, after which the excess nuclei apparently disintegrated. Howard (1931) also reported the fusion of swarm cells and subsequent karyogamy in Physarum polycephalum. Much of the disagreement of previous investigators has been caused by the conflicting results obtained from studying different species. Most of the investigators have concentrated on members of the Physarales; Reticularia is one of the few genera belonging to other orders. The present study was undertaken in the belief that a more comprehensive and accurate picture of the life cycle could be obtained by using members of several families.
A new approach for mobile communication: web services using flexible services architecture

Web services are driving the next generation of mobile computing applications by providing a thick abstraction layer that masks the operating systems for any given device from the developer. Major platform vendors are now rolling out revolutionary tools aimed at simplifying the creation and deployment of web services. The authors have created a mobile web service based on the flexible services architecture model for mobile communication. This paper presents a new approach to building flexible services architecture (FSA) based web services, and outlines the details of a sample web service that the authors have developed using the flexible services architecture. The translator web service developed by the authors demonstrates the flexibility and applicability of the FSA. This approach could be quite helpful for developing any web service and for building mobile communication applications.
Comparing provider perceptions of access and utilization management in full-risk and no-risk Medicaid programs for adults with serious mental illness.

This article compares provider perceptions of access to services and utilization management (UM) procedures in two Medicaid programs in the same state: a full-risk capitated managed care (MC) program and a no-risk, fee-for-service (FFS) program. Survey data were obtained from 198 mental health clinicians and administrators. The only difference found between respondents in the FFS and MC sites was that outpatient providers in the MC site reported significantly lower levels of access to high-intensity services than did providers in the FFS site (p<.001). Respondents in the two sites reported similar attitudes toward UM procedures, including a strong preference for internal over external UM procedures. These findings support the conclusion that through diffusion of UM procedures, all care in the Medicaid program for persons with a serious mental illness is managed, regardless of risk arrangement. Implications for mental health services and further research are discussed.
Usefulness of serial radionuclide monitoring during graded nitroglycerin infusion for unstable angina pectoris for determining left ventricular function and individualized therapeutic dose.

Abstract Using serial invasive hemodynamics in concert with noninvasive radionuclide monitoring of left ventricular (LV) function, 20 patients with unstable angina were evaluated during incremental infusion of intravenous nitroglycerin. Of 20 patients, 17 demonstrated a favorable hemodynamic response and dose responses could be determined for individual patients. There was excellent agreement between hemodynamic and noninvasive radionuclide measurements, and patient responses could be inferred from the radionuclide data alone. Cardiac output improved by 29% (mean 4.7 ± 1.2 to 6.0 ± 1.3), LV ejection fraction increased an average of 0.11 (0.39 ± 0.14 to 0.50 ± 0.16) and diastolic function as assessed by peak filling rate improved from 1.80 ± 0.60 end-diastolic volumes/s to 2.70 ± 0.90. Changes in systolic blood pressure and heart rate were not predictive of hemodynamic response. The dose of nitroglycerin necessary to produce maximal hemodynamic benefit was variable (mean 98 μg/min, range 48 to 144). In 7 patients, nitroglycerin caused excessive decreases in pulmonary arterial wedge pressure and adverse hemodynamics that corrected with intravenous fluids, allowing continued administration of intravenous nitroglycerin with improvement in hemodynamic status. In 15 patients, peak systolic pressure-end-systolic volume relations were assessed to define possible changes in LV contractility induced during nitroglycerin infusion. In 12 of these patients, this relation was linear, suggesting altered loading rather than augmented contractility as nitroglycerin's mechanism of action. In 3 patients a downward and rightward shift of the systolic relation was seen, suggesting that significant underloading with nitroglycerin was associated with depressed contractility.
Multiple quantum spin-echo spectroscopy

Abstract The generation of nuclear magnetic double quantum echoes and their detection by two-dimensional Fourier transform spectroscopy is reported for partially aligned one-deuteron systems in a nematic liquid crystal. Phase-cycling techniques which suppress detection of unwanted coherences have been developed, and the transverse decay rates of double quantum coherences are found to agree quantitatively with relaxation results obtained by more conventional methods.
The Smalltalk-76 programming system design and implementation

This paper describes a programming system based on the metaphor of communicating objects. Experience with a running system shows that this model provides flexibility, modularity and compactness. A compiled representation for the language is presented, along with an interpreter suitable for microcoding. The object-oriented model provides naturally efficient addressing; a corresponding virtual memory is described which offers dense utilization of resident space.
INFLUENCE OF ELECTRICAL STIMULATION ON CERTAIN CHARACTERISTICS OF HEAVY‐WEIGHT BEEF CARCASSES

Eight heavy-weight, grain-fed cattle (475–550 kg steers) were slaughtered and the right sides were electrically stimulated (50 impulses, 440 volts, 5 amps, 60 cycles per set) within 1 hr postmortem and before chilling. Measurements of pH were taken at 1, 6, 12 and 24 hr. Steaks were removed at 24 hr for palatability, fragmentation and sarcomere length determinations. Significant differences were observed for pH values at 1 hr (P 0.05) were observed for 12 hr or 24 hr pH values. Quality evaluations revealed that electrical stimulation resulted in improvements in lean color uniformity. Electrically stimulated beef also had less panel-detectable connective tissue amount and higher ratings for tenderness, flavor and overall palatability than unstimulated beef. Neither sarcomere length nor myofibril fragmentation index differed significantly (P > 0.05) between treatments. This study suggests that electrical stimulation is as effective in improving quality and palatability of heavy-weight, grain-fed beef as previous research has shown it to be in improving these characteristics in light-weight, short-fed or grass-fed beef.
PIXE ANALYSIS OF DRY DEPOSITION COLLECTED BY A CONTINUOUS SAMPLER USING A MODIFIED BETA-ATTENUATION DUST MONITOR

A high time-resolution system for dry deposition measurement was developed. This employed a modified beta-attenuation dust monitor and PIXE analysis in order to characterize the process of dry deposition. It was demonstrated that PIXE analysis can detect the presence of Al, Si, S and Fe in dry deposition samples for a one-hour sampling time.
EFFECT OF THERAPEUTIC DOSES OF COLCHICINE ON OXIDATIVE ENZYMES IN THE INTESTINE.

THE biological effects of colchicine have been thoroughly investigated as to its therapeutic effectiveness in gout1, and to its property of inducing metaphase arrest in dividing cells2. Investigations concerning its specific effects on the enzymes which are amenable to histochemical methods have been relatively few. However, alkaline phosphatase3 and uric acid riboside phosphorylase4 have been shown to be decreased at a dose-level of 1 mg/kg. Xanthine oxidase and xanthine dehydrogenase, on the other hand, have been shown to be elevated, following a similar dose, in rat serum5.
High-precision globally-referenced position and attitude via a fusion of visual SLAM, carrier-phase-based GPS, and inertial measurements

A novel navigation system for obtaining high-precision globally-referenced position and attitude is presented and analyzed. The system is centered on a bundle-adjustment-based visual simultaneous localization and mapping (SLAM) algorithm which incorporates carrier-phase differential GPS (CDGPS) position measurements into the bundle adjustment in addition to measurements of point features identified in a subset of the camera images, referred to as keyframes. To track the motion of the camera in real-time, a navigation filter is employed which utilizes the point feature measurements from all non-keyframes, the point feature positions estimated by bundle adjustment, and inertial measurements. Simulations have shown that the system obtains centimeter-level or better absolute positioning accuracy and sub-degree-level absolute attitude accuracy in open outdoor areas. Moreover, the position and attitude solution only drifts slightly with the distance traveled when the system transitions to a GPS-denied environment (e.g., when the navigation system is carried indoors). A novel technique for initializing the globally-referenced bundle adjustment algorithm is also presented which solves the problem of relating the coordinate systems for position estimates based on two disparate sensors while accounting for the distance between the sensors. Simulation results are presented for the globally-referenced bundle adjustment algorithm which demonstrate its performance in the challenging scenario of walking through a hallway where GPS signals are unavailable.
Developmental programs of lung epithelial progenitors: a balanced progenitor model

The daunting task of lung epithelium development is to transform a cluster of foregut progenitors into a three-dimensional (3D) tubular network with distinct cell types distributed at their appropriate locations. A complete understanding of lung development needs to address not only how, but also where, different cell types form. We propose that the lung epithelium forms through regulated deployment of three developmental programs: branching morphogenesis to expand progenitors and build a tree-like tubular network, airway differentiation to specify cells for the proximal conducting airways, and alveolar differentiation to specify cells for the peripheral gas exchange region. Each developmental program has its unique morphological features and molecular control mechanisms; their spatiotemporal coordination can be accounted for in a balanced progenitor model where progenitors balance between alternative developmental programs in response to spatiotemporal cues. This model integrates progenitor morphogenesis and differentiation, and provides new insights to lung immaturity in preterm birth and lung evolution. Advanced gene targeting and 3D imaging tools are needed to achieve a comprehensive understanding of lung epithelial progenitors on molecular, cellular, and morphological levels. For further resources related to this article, please visit the WIREs website. Conflict of interest: The authors have declared no conflicts of interest for this article.
EVOLUTION OF A QUASI-STATIONARY STATE

To elucidate the time development of quasi-stationary states, a simple barrier penetration problem has been studied. Both approximate expressions and numerical results for some parameters were obtained for the decay rate. First, irregular oscillations occur for a short time. Second, the exponential region follows. Third, further oscillations occur during which the decay rate dips to negative values, so that the probability of finding the undecayed system increases briefly at several times. Fourth and finally, the decay rate decreases like an inverse power of the time.
The active site of acidic aluminosilicate catalysts

The availability of solid acidic catalysts based on zeolite ZSM-5 make possible observations on the nature and the absolute rate behaviour of the individual protonic sites. Tetrahedral aluminium atoms are the highly reactive ingredients, even at levels of parts per million, or less. Turnover numbers for several hydrocarbon reactions equal and exceed familiar enzymatic turnover values. Intensive catalytic activities can result from aluminium levels likely to be ignored by the experimenter.
Tourism as public culture: Horne's ideological commentary on the legerdemain of tourism

In 1992 Donald Horne–respected Australian author of The Lucky Country, The Great Museum… and The Public Culture…–produced an entertaining but enlightening work (The Intelligent Tourist) on the role and function of tourism as the modern form of secular pilgrimage. In this text, Horne perceptively explored tourism as public culture –the fashions by which governments and interested parties capture national capitals, towns, villages, museums, art galleries, ancient temples, monuments, festivals and other interpreted performances in order to project the celebrated narratives and/or the ordinary vistas of a given people, its places, and its pasts. In 1994, King reviewed Horne's examination of the makebelieve of public culture in tourism, but appears to have overlooked much of the subtle insight with which Horne examined the objectifications and inspected the commodifications of contemporary tourism, and the exteriority of various tourism presentations. Horne's powerful scrutiny of intelligence-making in the articulations of tourism warrants fuller critique; this current paper therefore recrystallises Horne's work to highlight not only the skilled legerdemain of tourism practitioners in manufacturing preferred versions of public culture, but also the rich and acerbic insight that Horne himself brings to analyses of the ideological ‘power’ of invented presentation in tourism. Thereby, the paper attempts to distill a number of large issues on evocative material symbolism that Horne insists are central to the normalisations at work today in the projected public culture of post-modern ‘nationalist’ tourism, where that representation of tourism serves as a coding machine in the interests of certain or various priviliged groups.Copyright © 1999 John Wiley & Sons, Ltd.
Synthesis of trans bis-alkynyl complexes of Co(III) supported by a tetradentate macrocyclic amine: A spectroscopic, structural, and electrochemical analysis of π-interactions and electronic communication in the CCMCC structural unit

Abstract Alkynyl complexes of the type trans-[Co(cyclam)(CCR)2]OTf have been prepared and characterized by UV–Vis spectroscopy, 1H NMR, vibrational spectroscopy (infrared and Raman), and cyclic voltammetry. Where appropriate the data is compared to the corresponding Cr(III) and Rh(III) complexes. Though the arylalkynyl ligands have been shown to act as π-donors for the corresponding Cr(III) complexes, vibrational spectroscopy suggests that the π-interactions between the arylalkynyl ligands and Co(III) are quite weak, and that the more electron withdrawing trifluoropropynyl ligand likely behaves as a weak π-acceptor toward Co(III). X-ray crystal structures for trans-[Co(cyclam)(CCCF3)2]OTf and trans-[Cr(cyclam)(CCCF3)2]OTf are also reported and analysis of the M C and C C bond lengths are consistent with this understanding of the trifluoropropynyl ligand. Cyclic voltammetry of the trans-[Co(cyclam)(CCR)2]OTf complexes demonstrates that when R = C6H5 or p-C6H4CH3, the CoIII/II reduction wave is chemically irreversible. However, when R = p-C6H4CF3, p-C6H4CN, or CF3, the CoIII/II reduction wave is chemically reversible. This suggests that the more electron withdrawing alkynyl ligands become π-acceptors toward the reduced form of cobalt. Finally, the ferrocenyl capped trans-[M(cyclam)(CCFc)2]OTf complexes (where M = Co(III) and Rh(III)) were prepared and studied. Cyclic voltammetry shows only a single 2e− wave for the ferrocenyl termini, indicating little to no electronic communication through the organometallic backbone.
Thermal and oxidation chemistry of coal at low temperatures

Abstract The chemical reactions which occur when Illinois No. 6 (hv C) and Rawhide (SBB C) coals are thermally pretreated at 100°C and when Illinois No. 6 coal is subsequently oxidized at 100°C with O2 have been studied using in-situ FT-i.r. differende spectroscopy. Significant spectroscopic changes were seen. Vacuum drying at 100°C resulted in the decomposition of carboxylic acid species to form a variety of new carbonyl species (in Rawhide) and decarboxylated or decarbonylated coal (Illinois No. 6). Oxidation of predried Illinois No. 6 coal leads to the formation of new carbonyl species. The assumption that drying does not alter the chemical composition of coal may not be correct. Thus, overall spectroscopic (and chemical) changes observed in moderate temperature reaction studies may depend upon sample pretreatment, drying and storage. In addition, the time/temperature profile used in a reaction study may affect the overall changes observed by altering the relative contribution of the different reactions.
Nucleotide sequence relationships among thirty peanut stunt virus isolates determined by competition hybridization

The nucleotide sequence homology among 30 peanut stunt virus (PSV) isolates was determined. The isolates divided into two groups with little homology between them but extensive homology among their members. Only one isolate had nonoverlapping partial homology with both groups.
Immunocytochemical localization of the stress-induced DpsA protein in the cyanobacterium Synechococcus sp. strain PCC 7942

Proteins of the Dps family are divergent ferritins that have been shown to bind DNA with high affinity during periods of nutrient and oxidative stress. Such binding protects the chromosome from peroxide attack. Surprisingly, we show by immunocytochemistry that the cyanobacterial Dps homolog, DpsA, localizes preferentially to the thylakoid membrane in Synechococcus sp. strain PCC7942. We propose that two DpsA pools are functioning in this species--an insoluble fraction bound to the chromosome, and a soluble fraction acting as a ferritin involved metal homeostasis of the photosynthetic apparatus. This model is presented in light of recent work on the E. coli Dps protein showing that DNA binding is regulated by the metal-binding capacity of the Dps complex (Frenkiel-Krispin et al. 2001). Additionally, the pattern of DpsA localization in cells as they progress through the growth curve suggests that the DpsA complex may be involved in metal ion transport across the cell envelope.
The Effect of Water Soaking, Brining and Cooking Procedure on Tenderness of Broilers

Abstract Experiments were conducted to determine the effects of salt brining time, water soaking, and cooking procedures on the tenderness of broilers. In all experiments there were no significant differences in shear values of meat from birds that were either smoked or oven-roasted. Meat from birds that were soaked in salt brine 16 or 32 hours before either smoking or oven-roasting had significantly lower shear force values than meat from unbrined birds. There were no significant differences in shear values between light and dark meat from birds brined for either 16 or 32 hours while shear values for light meat were significantly higher than dark meat from unbrined birds. When broilers were either unbrined or soaked for 32 hours in brine or tap water, the meat from water soaked birds had numerically higher shear force values than meat from unbrined birds. Meat from both water soaked and unbrined birds had significantly higher shear force values than meat from brined birds. Microbiological examination of broilers after smoking showed low levels of total aerobes and an absence of coliforms.
An Empirical Test of Conclusions from Effective Schools Research.

Abstract Effective schools variables identified in several literature reviews were collapsed into 6 constructs, and the independent effect of each construct was empirically tested on student achievement level. The data for this analysis were taken from the National Educational Longitudinal Study for the years 1988, 1990, and 1992. The regression analysis of the data indicates that the most important effective schools characteristics are an achievement-oriented school culture, principal autonomy in hiring and firing teachers, and high teacher morale. No evidence was found that teacher empowerment, teacher education level, most principal influences, and quality of relations between the administration and the school are related to student performance.
A hierarchical approach to the molecular modeling of diffusion and adsorption at nonzero loading in microporous materials

Abstract A new hierarchical approach is presented for the modeling of small molecules at nonzero concentrations in microporous materials. This approach is complementary to other methods recently appearing in the literature; it is targeted for systems with pores that are well defined, large enough to host multiple molecules, and energetically uncorrugated in the interior. Statistical mechanical partition functions are calculated on molecular-level models and used as input to coarse-grained models, to predict both adsorption isotherms and self-diffusion coefficients. Certain physically reasonable simplifying approximations are employed to make the partition functions tractable. The approach is demonstrated on the model system of methane in siliceous zeolite ZK4 at 300 K , and the results are judged in comparison to those from traditional grand canonical Monte Carlo and molecular dynamics simulations. The adsorption isotherm is predicted to a high degree of accuracy across a large pressure range. The predicted trends in the self-diffusion coefficient are in qualitative agreement with the molecular dynamics results, but there is some quantitative disagreement at the lowest and highest adsorbate loadings.
Studies on the mechanism of action of puromycin aminonucleoside in L cells.

Abstract 1. 1. Puromycin aminonucleoside preferentially inhibits ribosomal RNA synthesis in L cells while at the same time sparing DNA and protein synthesis. This effect has been examined further and, using radioactive puromycin aminonucleoside, information has been obtained regarding the metabolism of this compound. 2. 2. Equimolar concentrations of adenosine and guanosine delayed, but did not prevent, the RNA inhibitory effect of puromycin aminonucleoside. Furthermore, the utilization of exogenous [ 14 C]adenosine was inhibited to the same extent as was [ 14 C]uridine utilization. It therefore seems unlikely that puromycin aminonucleoside inhibits RNA synthesis in this system by interfering directly with purine synthesis de novo . 3. 3. The RNA synthetic capacity of puromycin aminonucleoside-treated cells began to recover only after about 20 h in drug-free medium, and the presence of adenosine did not hasten this process. This finding correlated well with the lag in the resumption of growth by puromycin aminonucleoside-treated cells. 4. 4. The DNA-dependent RNA polymerase activity from L-cell nuclei was inhibited to a small extent (20 %) by puromycin aminonucleoside. 5. 5. Experiments using radioactive puromycin aminonucleoside demonstrated that L cells metabolized significant amounts of this drug to compounds tentatively identified as phosphorylated 3′-amino-3′-deoxyadenosine derivatives. No substantial incorporation of puromycin aminonucleoside or 3′-amino-3′-deoxyadenosine into L-cell RNA could be demonstrated.