cssi/SciSciGPT-SciSciNet huggingface dataset:
The Stanford experience of heart transplantation over five decades.

Aims Since 1968, heart transplantation has become the definitive treatment for patients with end-stage heart failure. We aimed to summarize our experience in heart transplantation at Stanford University since the first transplantation performed over 50 years ago. Methods and results From 6 January 1968 to 30 November 2020, 2671 patients presented to Stanford University for heart transplantation, of which 1958 were adult heart transplantations. Descriptive analyses were performed for patients in 1968-95 (n = 639). Stabilized inverse probability weighting was applied to compare patients in 1996-2006 (n = 356) vs. 2007-19 (n = 515). Follow-up data were updated through 2020. The primary endpoint was all-cause mortality. Prior to weighting, recipients in 2007-19 vs. those in 1996-2006 were older and had heavier burden of chronic diseases. After the application of stabilized inverse probability weighting, the distance organ travelled increased from 84.2 ± 111.1 miles to 159.3 ± 169.9 miles from 1996-2006 to 2007-19. Total allograft ischaemia time also increased over time (199.6 ± 52.7 vs. 225.3 ± 50.0 min). Patients in 2007-19 showed superior survival than those in 1996-2006 with a median survival of 12.1 vs. 11.1 years. Conclusion In this half-century retrospective descriptive study from one of the largest heart transplant programmes in the USA, long-term survival after heart transplantation has improved over time despite increased recipient and donor age, worsening comorbidities, increased technical complexity, and prolonged total allograft ischaemia time. Further investigation is warranted to delineate factors associated with the excellent outcomes observed in this study.
Symbolic mathematics and mathematical functions

This chapter discusses symbolic mathematical operations, including algebraic operations on real scalar variables, algebraic operations on real vector variables, and algebraic operations on complex scalar variables. The concept of a mathematical function is explained and trigonometric functions, logarithms and the exponential function are described in this section. The principal facts and ideas behind trigonometric functions, vectors, and algebra are also listed in this segment. Algebraic operations on real scalar variables are first discussed in the chapter. The basics of algebra are briefly reviewed and algebraic manipulations are further described in another segment of the chapter. Trigonometric functions include information on trigonometric identities, mathematical limits and a useful approximation, general properties of trigonometric functions, and inverse trigonometric functions. Vectors and coordinate systems is the next section of the chapter. It describes vectors in two dimensions, vector algebra in two dimensions, vectors and coordinate systems in three dimensions, and vector algebra in three dimensions. Imaginary and complex numbers and problem solving and symbolic mathematics are the other topics discussed in a section that forms a part of the chapter. The chapter basically introduces symbolic mathematics, which involves the manipulation of symbols instead of performing numerical operations. It presents the algebraic tools needed to manipulate expressions containing real scalar variables, real vector variables, and complex scalar variables. It also introduces ordinary and hyperbolic trigonometric functions, exponentials, and logarithms. A brief introduction to the techniques of problem solving is also included in the chapter.
PITSLRE: PITSLRE protein kinase (vertebrates) (p58Gta, cdc2L1)

PITSLRE protein kinase was isolated as an associated component of mammalian β-l,4-galactosyltransferase preparations. The predicted structure of this protein kinase indicated that it was closely related to the cell division control protein kinase Cdc2. Minimal overexpression of p58Gta led to a delay in the CHO cell cycle at late telophase. Additionally, transient overexpression of the cDNA in COS cells resulted in an increase in β-l,4-galactosyltransferase enzyme activity. At this time, however, the exact function of this protein kinase has not been established. At present, 10 different PITSLRE isoforms have been identified by cross-reactivity with p58 antibodies and by molecular cloning from human cell lines. Five of these isoforms arise by alternative splicing from one gene, while the others appear to arise from highly duplicated sequences. The central kinase domain of PITSLREβ1 is 42% identical to Cdc2, and it contains residues equivalent to T14, Y15, and T161, which are involved in the regulation of Cdc2. Isoforms differ in the extent and nature of the N-terminal domains. The α and β isoforms also have four distinct amino acid differences in the C-terminal domain.
Building segmentation based human-friendly human interaction proofs (HIPs)

Human interaction proofs (HIPs) have become common place on the internet due to their effectiveness in deterring automated abuse of online services intended for humans. However, there is a co-evolutionary arms race in progress and these proofs are becoming more difficult for genuine users while attackers are getting better at breaking existing HIPs. We studied various popular HIPs on the internet to understand their strength and human friendliness. To determine HIP strength, we adopted a direct approach of building computer attacks using image processing and machine learning techniques. To understand human-friendliness, a sequence of users studies were conducted to investigate HIP character recognition by humans under a variety of visual distortions and clutter commonly employed in reading-based HIPs. We found that many of the online HIPs are pure recognition tasks that can be easily broken using machine learning. The stronger HIPs tend to pose a combination of segmentation and recognition challenges. Further, the HIP user studies show that given correct segmentation, computers are much better at HIP character recognition than humans. In light of these results, we propose that segmentation-based reading challenges are the future for building stronger human-friendly HIPs. An example of such a segmentation-based HIP is presented with a preliminary assessment of its strength and human-friendliness.
Anisotropic Mesh Adaptation for Variational Problems Using Error Estimation Based on Hierarchical Bases

Anisotropic mesh adaptation has been successfully applied to the numerical solution of partial differential equations but little considered for variational problems. In this paper, we investigate the use of a global hierarchical basis error estimator for the development of an anisotropic metric tensor needed for the adaptive finite element solution of variational problems. The new metric tensor is completely a~posteriori and based on residual, edge jumps and the hierarchical basis error estimator. Numerical results show that it performs comparable with existing metric tensors based on Hessian recovery. A few sweeps of the symmetric Gaus-Seidel iteration for solving the global error problem prove sufficient to provide directional information necessary for successful mesh adaptation. .
Interrogative Logic as a General Theory of Reasoning

The interrogative approach to reasoning and argumentation is not just one approach to its subject among many. Both historically and systematically, it is arguably the first and foremost theory of reasoning.
Victim Participation in Proceedings and Sentencing in Europe

The article reviews the different ways in which victims can influence the course and outcome of criminal proceedings in different European criminal justice systems. The range is from some jurisdictions (such as Greece, the Netherlands and Portugal) where the victim can appear only in the capacity as witness, to others (such as Finland) where there is a general right to prosecute. Even in the systems providing victims with the greatest opportunity for participation, the victim in practice generally leaves prosecution to the public prosecutor. The article concludes by arguing that no one system is ideal from the point of view of the victim.
A structured retroviral RNA element that mediates nucleocytoplasmic export of intron-containing RNA.

A common feature of gene expression in all retroviruses is that unspliced, intron-containing RNA is exported to the cytoplasm despite the fact that cellular RNAs which contain introns are usually restricted to the nucleus. In complex retroviruses, the export of intron-containing RNA is mediated by specific viral regulatory proteins (e.g., human immunodeficiency virus type 1 [HIV-1] Rev) that bind to elements in the viral RNA. However, simpler retroviruses do not encode such regulatory proteins. Here we show that the genome of the simpler retrovirus Mason-Pfizer monkey virus (MPMV) contains an element that serves as an autonomous nuclear export signal for intron-containing RNA. This element is essential for MPMV replication; however, its function can be complemented by HIV-1 Rev and the Rev-responsive element. The element can also facilitate the export of cellular intron-containing RNA. These results suggest that the MPMV element mimics cellular RNA transport signals and mediates RNA export through interaction with endogenous cellular factors.
NADP-dependent glutamate dehydrogenase from a facultative methylotroph, Pseudomonas sp. strain AM1

The NADP-dependent glutamate dehydrogenase (EC 1.4.1.4.) elaborated by the methylotrophic bacterium Pseudomonas sp. strain AM1 when growing on succinate and ammonium chloride was studied. The enzyme, which has a pH optimum of 9.0, was purified 140-fold and shown to have Km values of 20.2 mM, 0.76 mM, 0.033 mM, and 31.6 mM for ammonia, alpha-ketoglutarate, NADPH, and glutamate, respectively. The native molecular weight was determined by polyacrylamide gel electrophoresis to be 190,000, and electrophoresis under denaturing conditions in the presence of sodium dodecyl sulfate revealed a minimum molecular weight of 50,000. The enzyme was highly specific; NADH was unable to replace NADPH in the reaction, various alpha-keto acids could not replace alpha-ketoglutarate, and neither methylamine nor hydroxylamine could substitute for ammonia. Glutamate dehydrogenase was synthesized by the bacteria only when ammonia was its nitrogen source and was repressed if methylamine or nitrate were provided as sources of nitrogen instead of ammonia.
Potent agonists of growth hormone-releasing hormone. Part I

Analogs of the 29 amino acid sequence of growth hormone-releasing hormone (GH-RH) with agmatine (Agm) in position 29 have been synthesized by the solid phase method, purified, and tested in vitro and in vivo. The majority of the analogs contained desaminotyrosine (Dat) in position 1, but a few of them had Tyr1, or N-MeTyr1. Some peptides contained one or more additional l- or d-amino acid substitutions in positions 2, 12, 15, 21, 27, and/or 28. Compared to the natural sequence of GH-RH(1-29)NH2, [Dat′,Ala15]GH-RH(1-28)Agm (MZ-3-191) and [d-Ala2,Ala15]GH-RH(l-28)Agm (MZ-3-201) were 8.2 and 7.1 times more potent in vitro, respectively. These two peptides contained Met27. Their Nle27 analogs, [DatI,Ala15,Nle27]GH-RH(1-28)Agm(MZ-2-51), prepared previously (9), and [D-Ala2,Ala15,Nle28]GH-RH(l-28)Agm(MZ-3-195) showed relative in vitro potencies of 10.5 and 2.4, respectively. These data indicate that replacement of Met27 by Nle27 enhanced the GH-releasing activity of the analog when the molecule contained Dat1-Ala2 residues at the N-terminus, but peptides containing Tyr1-D-Ala2 in addition to Nle27 showed decreased potencies. Replacement of Ser28 with Asp in multi-substituted analogs of GH-RH(l-28)Agm resulted in a decrease in in vitro potencies compared to the parent compound. Thus, the Ser28-containing MZ-2-51, and [Dat1,Ala15,d-Lys21,Nle27]GH-RH(l-28)Agm, its Asp28 homolog (MZ-3-149), possessed relative activities of 10.5 and 5.6, respectively. In vivo after the iv injection, the analogs [Dat1,Ala15,Nle27,Asp28]GH-RH(l-28)Agm (MZ-3-149), [Dat1, Ala15]GH-RH(l-28)Agm, (MZ-3-191) and [d-Ala2,Ala,5]GH-RH(l-28)Agm (MZ-3-201) showed a potency equivalent to 7.6, 4.9 and 3.3 times that of GH-RH(1-29)NH2, respectively, at 5 min and 20.3, 4.3 and 1.7 times higher, respectively, at 15 min. After sc administration, analogs MZ-3-149, MZ-3-191, and MZ-3-201 were shown to be 63.7, 55.2 and 56.8 times more potent than the parent hormone at 15 min and 57.6, 60.6, and 42.6 times more active, respectively, at 30 min. In addition, MZ-3-149 had prolonged GH-releasing activity as compared to the standard, and proved to be more potent than MZ-2-51, the most active member of our previous series (8, 9). Our studies indicate that very potent GH-RH analogs can result from the combination of agmatine in position 29 with other substitutions.
Factors that Affect BSFC and Emissions for Diesel Engines: Part 1 - Presentation of Concepts

Parametres qui influencent les emissions polluantes et la consommation specifique de carburant mesuree au frein d'un moteur diesel. Concepts de base
Stokes' first problem for some non-Newtonian fluids: Results and mistakes

The well-known problem of unidirectional plane flow of a fluid in a half-space due to the impulsive motion of the plate it rests upon is discussed in the context of the second-grade and the Oldroyd-B non-Newtonian fluids. The governing equations are derived from the conservation laws of mass and momentum and three correct known representations of their exact solutions given. Common mistakes made in the literature are identified. Simple numerical schemes that corroborate the analytical solutions are constructed.
Role of Cyanide Species in the Reduction of NO by CH4over Co–ZSM-5

Abstract In situ infrared observation during the reduction of NO by CH 4 over Co–ZSM-5 reveals the presence of CN species. The reactivity of these species has been probed by exposing them to NO 2 , O 2 , or NO while monitoring their rate of disappearance. In a complementary set of experiments, mass spectrometry was used to identify the reaction products as N 2 and CO 2 . At 450°C the rate coefficients for the consumption of CN are 8.5×10 −5 , 1.9×10 −6 , and 3.3× 10 −7 s −1 ppm −1 for reaction in NO 2 , O 2 , and NO, respectively. The reactivity of CN is sufficiently high for these species to be considered reaction intermediates in the formation of N 2 and CO 2 during the reduction of NO by CH 4 in the presence of O 2 .
Expected value expansions in rooted graphs

When G is a rooted graph where each edge may independently succeed with probability p, we consider the expected number of vertices in the operational component of G containing the root. This expected value EV(G; p) is a polynomial in p. We present several distinct equivalent formulations of EV(G; p), unifying prior treatments of this topic. We use results on network resilience (introduced by Colbourn) to obtain complexity results for computing EV(G; p). We use some of these formulations to derive closed form expressions for EV(G; p) for some specific classes of graphs. We conclude by considering optimality questions for rooted graphs, root placement and some counterexamples.
Concurrent engineering deployment: an enhanced “customer product” approach

Abstract This paper examines the utilization of graphic capabilities of computers into a new digressive approach for concurrent engineering that combines the concepts of quality function deployment, reverse engineering and virtual reality.
Immune response gene control of antibody specificity

Abstract The expression of the histocompatibility-linked PLL Ir gene was investigated in guinea pig B cells. Strain 2 and F 1 (2 × 13) guinea pigs, immunized with the αDnp-Lys 9 , produce both T cells and antibody which are equally discriminatory for αDnp-Lys 9 . In contrast strain 13 (PLL Ir gene negative) guinea pigs immunized with αDnp-Lys 9 do not develop specific T-cell responses and the antibody produced while restricted in heterogeneity cannot differentiate the immunizing antigen from Dnp-OH. However, if in a F 1 (2 × 13) environment, PLL Ir gene-negative B cells are provided with F 1 (2 × 13) T cells they express the ability to make antibody as specific and discriminatory as the antibody produced by PLL Ir gene-positive B cells. These findings strongly suggest that in the guinea pigs the PLL Ir gene defect is localized to the T cells and that the repertoire of specificity of B cells is similar if not identical in both responder and nonresponder animals. In addition these observations support the notion that the cellular locus for the PLL Ir gene expression in the guinea pigs is limited to T cells and not to macrophages and B lymphocytes.
Ground-layer response to group selection with legacy-tree retention in a managed northern hardwood forest

We examined the effects of group selection with legacy-tree retention on ground-layer or understory diversity and composition in an uneven-aged northern hardwood forest in the Upper Peninsula of Mi...
Treating ACL injuries in young moderately active adults

Individual patient factors should guide the decision on whether to surgically reconstruct Many who delay surgery end up having reconstruction anyway PAUL RAPSON/ SPL Currently, the clinical indication for anterior cruciate ligament (ACL) reconstruction takes into account both patient related and knee related factors. In an effort to better identify these factors, Frobell and colleagues performed a randomized clinical trial comparing two treatment strategies for young moderately active patients with a torn ACL. Patients were randomized to “acute” ACL reconstruction (within 10 weeks) or “optional delayed” ACL reconstruction (rehabilitation with the option for delayed surgery).1 In 2010, the authors published two year outcomes that reported no difference between the two treatment arms in the primary outcome (knee injury and osteoarthritis outcome score; KOOS) or secondary outcomes of SF-36 and Tegner activity scale (TAS). However, supplementary data provided in an appendix reported 29 subsequent meniscus tears in the “optional delayed” group, and by two years almost 40% of the patients in this group had already crossed over to ACL reconstruction surgery. In the linked study (doi:10.1136/bmj.f232), Frobell and colleagues report the five year outcomes for the trial.2 Similar to …
Mammals from the Palaeogene of the EurekaSound Formation: Ellesmere Island, Arctic Canada

La formation Eureka Sound dans l'ile Ellesmere,situee dans la zone arctique canadienne a approximativement 79° de latitude Nord, a livre diverses faunes de mammiferes qui ont un cachet Eicene inferieur a Eocene moyen. Un premier examen du materiel a montre la presence de plusieurs ordres: Proteutheria, Dermoptera. Rodentia, Pantodonta, carnivores et Perissodactyla. Associes a ces mammiferes on a un ensemble de vertebres inferieurs comprenant de nombreux restes de poissons, salamandres, alligators, lezards, serpents et differentes sortes de tortues et d'oiseaux. Ces ensembles constituent la premiere preuve paleontologique de la presence de faunes terrestres au Paleogene sous des latitudes elevees dans la region holarctique; elles posent de nouveaux problemes a propos de la paleobiogeographie environnements de la zone arctique pendant l'Eocene.
Activation of sp3 and sp2 CH bonds of oxygen containing heterocyclic molecules for alkylation and arylation reactions catalyzed by an iron complex

Abstract Activation of both sp3 and sp2 C H bonds is reported using an efficient iron(III) complex (1) of a ligand (N2,N6-bis(2,6-diisopropylphenyl)pyridine-2,6-dicarboxamide: L). The iron(III) complex showed catalytic activity of C C coupling reaction of oxygen containing heterocycles, e.g. tetrahydrofuran (THF), with various alkyl, allyl and aryl Grignard reagents under ambient reaction conditions. Complex 1 demonstrated excellent activity and reactions were completed within 30 min to 1 h. A high turnover frequency (TOF) of 1700 h−1 using a low catalyst loading of 0.02 mol% was obtained for the reaction. Interestingly, the catalyst was selective in activation of the C H bond adjacent to the oxygen in various oxygen containing heterocyclic molecules to yield 2-substitituted products.
Visual enhancement of laparoscopic nephrectomies using the 3-CCD camera

Many surgical techniques are currently shifting from the more conventional, open approach towards minimally invasive laparoscopic procedures. Laparoscopy results in smaller incisions, potentially leading to less postoperative pain and more rapid recoveries . One key disadvantage of laparoscopic surgery is the loss of three-dimensional assessment of organs and tissue perfusion. Advances in laparoscopic technology include high-definition monitors for improved visualization and upgraded single charge coupled device (CCD) detectors to 3-CCD cameras, to provide a larger, more sensitive color palette to increase the perception of detail. In this discussion, we further advance existing laparoscopic technology to create greater enhancement of images obtained during radical and partial nephrectomies in which the assessment of tissue perfusion is crucial but limited with current 3-CCD cameras. By separating the signals received by each CCD in the 3-CCD camera and by introducing a straight forward algorithm, rapid differentiation of renal vessels and perfusion is accomplished and could be performed real time. The newly acquired images are overlaid onto conventional images for reference and comparison. This affords the surgeon the ability to accurately detect changes in tissue oxygenation despite inherent limitations of the visible light image. Such additional capability should impact procedures in which visual assessment of organ vitality is critical.
A framework for rapid local area modeling for construction automation

Rapid 3D positioning and modeling in construction can be used to more effectively plan, visualize, and communicate operations before execution. It can also help to optimize equipment operations, significantly improve safety, and enhance a remote operator's spatial perception of the workspace. A new framework for rapid local area sensing and 3D modeling for better planning and control of construction equipment operation is described and demonstrated. By combining human-assisted graphical workspace modeling with pre-stored Computer-Aided Design (CAD) models and simple sensors (such as single-axis laser rangefinders and remote video cameras), modeling time can be significantly reduced while potentially increasing modeling accuracy.
Crystal chemical effects on the partitioning of trace elements between mineral and melt: An experimental study of melilite with applications to refractory inclusions from carbonaceous chondrites

The partitioning behavior of the trace elements Be, Sc, Ba, La, Ce, and Tm between melilite and liquid has been determined using stepwise integration of a Rayleigh fractionation equation for ion microprobe analyses of synthetic zoned melilite crystals. Distribution coefficients between melilite and liquid (D^(Mel/L)_i) were determined over the entire range of melilite + spinel crystallization for one bulk composition corresponding to that of an average Type B inclusion from the Allende C3V carbonaceous chondrite. Beryllium is incompatible in gehlenitic meliliters (e.g.,D^(Mel/L)B_e = 0.5 for X_(ak) = 0.3) but compatible in akermanitic melilites (e.g., D^(Mel/L)B_e = 1.9 for X_(Ak) = 0.75). Barium (D^(Mel/L)B_a = 0.04-0.05), Sc (D^(Mel/L)S_c = 0.01-0.02), La (D^(Mel/L)L_α ≤ 0.07-0.29), Ce (D^(Mel/L)C_e ≤ 0.05-0.21), and Tm (D^(Mel/L)T_m ≤ 0.03-0.14) are all incompatible in melilites in the range Ak25-Ak75. Variations in D^(Mel/L)i as a function of X_(Ak) are explicable in terms of a simple thermodynamic treatment of trace element partitioning based on crystal chemical considerations. Characteristic trace element zoning patterns are predicted for early crystallizing melilite from meliliterich Type B inclusions. For example, concentrations of the REEs in melilite should continually decrease with increasing degrees of crystallization, opposite the behavior normally expected of an incompatible element. Concentrations of Be should rise with increasing degrees of crystallization even when the element is compatible, again opposite the behavior normally expected of compatible elements. In general, zoning patterns of trace elements in melilite from Type B inclusions are consistent with those predicted for fractional crystallization from a melt in a closed system. Trace element zoning patterns in meteoritic melilite crystals constrain the origin and thermal histories of Ca-, Al-rich inclusions from carbonaceous chondrites.
Stability of a magnetized positive column between coaxial cylinders

Theoretical analysis for the stability of a diffusion dominated positive column between coaxial cylinders in the presence of an axial magnetic field is carried out under the assumptions of quasi-neutrality of charges and no sheath at the walls. Self-consistent infinitesimal perturbations of plasma density and electric potential, which satisfy the linearized governing equations to the same degree of approximation are used to derive the dispersion relation. The perturbations associated with aximuthal modes m ≤ 0 are stable for any gap size and plasma parameters. The stability of non-axisymmetric perturbations is studied for different gaps. It is found that the presence of inner cylinders increases the stability of a magnetized positive column and m = 2 defines the region of stability when the ratio of the radii of the inner and outer cylinders is less than 0·5. In the case of narrow gaps, higher and higher modes are excited. The minimum non-dimensional axial electric field at which the magnetized positive column between coaxial cylinders becomes unstable for different gaps is also determined.
Spatially resolved photoluminescence and transmission spectra of HgCdTe

We report new high-resolution scanning photoluminescence (PL) experiments in the mid-infrared (IR) portion of the spectrum. The samples investigated were Hg0.7Cd0.3Te epilayers grown on Cd0.96Zn0.04Te substrates. The influence of macrodefects and the annealing of samples on the PL signal were studied. Transmission spectra were used to map the optical path variations of the epilayer.
The California State University Journal Access Core Collection

This column is a departure from earlier Balance Points in that the contributions are in a question-and-answer format. I chose to ask contributors specific questions to provide focus within a large ...
Metabolic Biomarkers for Monitoring in Situ Anaerobic Hydrocarbon Degradation

During the past 15 years researchers have made great strides in understanding the metabolism of hydrocarbons by anaerobic bacteria. Organisms capable of utilizing benzene, toluene, ethylbenzene, xylenes, alkanes, and polycyclic aromatic hydrocarbons have been isolated and described. In addition, the mechanisms of degradation for these compounds have been elucidated. This basic research has led to the development of methods for detecting in situ biodegradation of petroleum-related pollutants in anoxic groundwater. Knowledge of the metabolic pathways used by anaerobic bacteria to break down hydrocarbons has allowed us to identify unique intermediate compounds that can be used as biomarkers for in situ activity. One of these unique intermediates is 2-methylbenzylsuccinate, the product of fumarate addition to o-xylene by the enzyme responsible for toluene utilization. We have carried out laboratory studies to show that this compound can be used as a reliable indicator of anaerobic toluene degradation. Field studies confirmed that the biomarker is detectable in field samples and its distribution corresponds to areas where active biodegradation is predicted. For naphthalene, three biomarkers were identified [2-naphthoic acid (2-NA), tetrahydro-2-NA, and hexahydro-2-NA] that can be used in the field to identify areas of active in situ degradation.
Development of a Model of Dispersion Parameters for Odour Transmission from Agricultural Sources

Abstract A mathematical model of the dispersion parameters in the Gaussian plume model is developed for calculating ground-level odour concentration and for analysing the effect of wind speed on odour concentration. The model has three coefficients. The dispersion parameters are expressed as functions of downwind distance and wind speed, with wind speed being the most important factor to affect downwind concentration of odour from an agricultural source. The model was investigated by using the Pasquill–Gifford data. The range of downwind distances for which the model is applicable is from 100 to 1000 m, the zone of interest for odour dispersion from agricultural sources. The model is shown to fit the Pasquill–Gifford data effectively. The non-linear regression results also show that there is a dominant coefficient that determines the final estimation of the model. The error caused by incorporating the wind speed into the model is random.
Mode coupling in partial reflections from the ionosphere at vertical incidence.

The effect of mode coupling has been calculated for radio waves partially reflected from the lower ionosphere at vertical incidence. Calculations were made for parameters appropriate to the partial reflection experiments (Belrose, 1970). The four reflection coefficients (two direct and two coupled) are calculated for a plane discontinuity using a matrix perturbation analysis. The ratios of coupled to direct reflection coefficients are calculated for a general one-dimensional reflecting layer using the coupled equations of Clemmow and Heading (1954). At the highest electron density considered, 10,000 per cu cm, about 10% of the reflected extraordinary wave amplitude might be due to coupling from the incident ordinary wave. The effect is smaller at lower electron density.
Knowledge Accumulation and Dissemination in MNEs: A Practice-Based Framework

This paper proposes that the mechanisms of external knowledge capture and internal knowledge transfer can best be understood at the micro-organizational level of Communities of Practice (CoPs) rather than at that of the subsidiaries' network. The paper then offers a model of the dynamics of organizational learning in network organizations, such as MNEs, which builds on this unit of analysis. This model: (i) clarifies the link between CoPs and Networks of Practice (NoPs), by offering a novel conceptual model of how knowledge, particularly tacit, embedded knowledge, is absorbed; and (ii) proposes a new link - that between CoPs and Internal Networks of Practice (INoPs), as another essential ingredient to knowledge accumulation and transfer within firms. We also propose that the firm-level architectural knowledge that is developed through INoPs is valuable and rare, and in combination with the component knowledge developed through NoPs, can create novel knowledge that may be a source of competitive advantage.
Adaptation of circuit-simulation algorithms to a simple parallel microcomputer structure

An inexpensive parallel microcomputer structure is presented as a medium for the simulation of physical systems modelled by ordinary differential equations, especially the simulation of large nonlinear circuits Several of the implications of this structure for the usual algorithms of nonlinear-circuit analysis are studied.
Magnesium deficiency: recognition and treatment in the emergency medicine setting.

Abstract Magnesium deficiency and its clinical manifestations are common in palients presenting to the emergency department. Assessment of the total body magnesium status of a patient is problematic since the serum magnesium concentration, the only readily available clinical test for this condition, may not be accurate in predicting the intracellular magnesium concentration. Therefore, empiric magnesium therapy should be considered in high-risk patients. Since magnesium participates in numerous metabolic processes in the body, a deficiency can affect multiple organ systems and present clinically in a variety of ways. Magnesium deficiency is reviewed in this paper with regard to therapeutic implications; specific treatment guidelines are given including dose, infusion rate, and magnesium preparation. Magnesium is also reviewed with regard to its homeostasis and metabolic role in the body. Special mention is made regarding precautions for use of magnesium in the setting of renal insufficiency.
An Image Processing Technique to Recover the Biomass Concentration in Algae Biofilm Photobioreactors

This paper reports a simple technique based on multispectral image processing that can be used to recover the biomass concentration of an algal biofilm photobioreactor. Monitoring the biomass concentration of a culture is critical in achieving successful algae cultivation for biofuel or food supplement production. In particular, non-invasive and rapid detection techniques that can provide estimates of the biomass concentration can significantly aid in providing delay-free process control feedback in large scale cultivation platforms. In this technique, the digital images of the biofilms of the cyanobacteria Anabaena variabilis were obtained under consistent lighting conditions and analyzed as a function of their biomass content. The image analysis was carried out using a custom Matlab code where the red, green and blue content of the images were correlated with the biomass concentration. The obtained correlation was consistent across biofilms generated from different stock cultures of varying culture age. Challenges facing application of the image processing technique for scaled up outdoor photobioreactors under various lighting conditions and color backgrounds were discussed.Copyright © 2012 by ASME
Intensification of catalytic olefin hydroformylation in CO2‐expanded media

CO2-expanded liquids (CXLs) are demonstrated to be effective reaction media for the catalytic hydroformylation of 1-octene. The performance of several rhodium catalysts, Rh(acac)(CO)2, Rh(acac)[P(OPh)3]2, Rh(acac)(CO)[P(OAr)3], and two phosphorous ligands, PPh3 and biphephos, was compared in neat organic solvents and in CXLs wherein more than 50% of the solvent volume is replaced with dense CO2 at relatively mild temperatures (30–90°C) and pressures ( 10), and aldehyde selectivity (∼90%) at the optimum CO2 content were either comparable to or better than values reported with other media and catalysts. Furthermore, the operating pressure (3.8 MPa) and temperature (60°C) for the CXL process are significantly milder than those reported for industrial hydroformylation processes. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Stress and coping in relation to metabolic control of adolescents with Type 1 diabetes.

The purpose of this study was to determine whether measures of anxiety, stress, and means of coping with stress differ in diabetic adolescents in good, fair, and poor metabolic control. Trait anxiety, perceived daily stress, and coping responses to a recent stressful event were assessed in 27 adolescents with Type 1 diabetes mellitus. Information also was obtained regarding the type of stressful events that subjects referred to in completing the coping measure, as well as their appraisals of the events. Hemoglobin A1 (HbA1) obtained at the time of the study was used as a measure of antecedent metabolic control. Based upon their HbA1, patients were divided into three metabolic control subgroups: good control (M = 8.4%; n = 8), fair control (M = 10.9%; n = 9), and poor control (M = 13.3%; n = 10). Patients in these subgroups were similar with regard to age, disease duration, and socioeconomic status. Results indicated that the subgroups did not differ on the anxiety and stress measures; however, analyses of the coping data indicated that patients in poor control employed significantly more wishful thinking and avoidance/help-seeking than did patients in good metabolic control. Furthermore, the metabolic control subgroups differed in the type of stressful events reported and their appraisals of the stressful events. These results support the hypothesis that the ways in which individuals with diabetes appraise and cope with stress is related to their metabolic control. The findings are discussed in relation to methodological issues and treatment implications.
Differential Expression of the Expression Site-associated Gene I Family in African Trypanosomes

A minimum of 20 different mRNA species encoding related members of the expression site-associated gene I (ESAG-I) family occur in metacyclic variant antigen type 4 bloodstream trypanosomes. None of these ESAG-I mRNAs are derived from the metacyclic variant antigen type 4 variant surface glycoprotein (VSG) gene expression site, and some appear to come from pseudogenes. The ESAG-Is are transcribed in both procyclic and bloodstream trypanosomes, but their mRNAs accumulate to a detectable steady state level only in bloodstream trypanosomes. At least five different groups of 3′-untranslated regions (3′-UTRs) are represented among these ESAG-I mRNAs, suggesting that the 3′-UTR does not contribute to their differential expression. Some ESAG-I mRNAs completely lack a 3′-UTR or have only a single nucleotide as a 3′-UTR. Transcription of the ESAG-Is is sensitive to α-amanitin, indicating that they are transcribed by a different RNA polymerase than the VSG genes. These results collectively demonstrate that ESAG-I's are a heterogeneous population that can be expressed independently of VSG genes, but like the VSG genes, their mRNAs are present in the bloodstream stage of the parasite and not in the procyclic stage.
Mesoporous organohydrogels from thermogelling photocrosslinkable nanoemulsions

We report the formation of mesoporous organohydrogels from oil-in-water nanoemulsions containing an end-functionalized oligomeric gelator in the aqueous phase. The nanoemulsions exhibit an abrupt thermoreversible transition from a low-viscosity liquid to a fractal-like colloidal gel of droplets with mesoscale porosity and solid-like viscoelasticity with moduli approaching 100 kPa, possibly the highest reported for an emulsion-based system. We hypothesize that gelation is brought about by temperature-induced interdroplet bridging of the gelator, as shown by its dependence on the gelator chemistry. The use of photocrosslinkable gelators enables the freezing of the nanoemulsion’s microstructure into a soft hydrogel nanocomposite containing a large fraction of dispersed liquid hydrophobic compartments, and we show its use in the encapsulation and release of lipophilic biomolecules. The tunable structural, mechanical and optical properties of these organohydrogels make them a robust material platform suitable for a wide range of applications. Mesoporous colloidal gels with solid-like viscoelasticity formed from oil-in-water nanoemulsions are reported. Gelation is thermoreversible and occurs through interdroplet bridging of an end-functionalized oligomer. The gels can be photocrosslinked to encapsulate lipophilic biomolecules for their subsequent release through ultraviolet photolysis.
Radiobiology for eye plaque brachytherapy and evaluation of implant duration and radionuclide choice using an objective function

Purpose: Clinical optimization of Collaborative Ocular Melanoma Study (COMS) eye plaque brachytherapy is currently limited to tumor coverage, consensus prescription dosage, and dose calculations to ocular structures. The biologically effective dose (BED) of temporary brachytherapy treatments is a function of both chosen radionuclide R and implant duration T. This study endeavored to evaluate BED delivered to the tumor volume and surrounding ocular structures as a function of plaque position P, prescription dose, R, and T. Methods: Plaque-heterogeneity-corrected dose distributions were generated with MCNP5 for the range of currently available COMS plaques loaded with sources using three available low-energy radionuclides. These physical dose distributions were imported into the PINNACLE{sup 3} treatment planning system using the TG-43 hybrid technique and used to generate dose volume histograms for a T = 7 day implant within a reference eye geometry including the ciliary body, cornea, eyelid, foveola, lacrimal gland, lens, optic disc, optic nerve, retina, and tumor at eight standard treatment positions. The equation of Dale and Jones was employed to create biologically effective dose volume histograms (BEDVHs), allowing for BED volumetric analysis of all ROIs. Isobiologically effective prescription doses were calculated for T = 5 days down to 0.01 days, with BEDVHs subsequentlymore » generated for all ROIs using correspondingly reduced prescription doses. Objective functions were created to evaluate the BEDVHs as a function of R and T. These objective functions are mathematically accessible and sufficiently general to be applied to temporary or permanent brachytherapy implants for a variety of disease sites. Results: Reducing T from 7 to 0.01 days for a 10 mm plaque produced an average BED benefit of 26%, 20%, and 17% for {sup 103}Pd, {sup 125}I, and {sup 131}Cs, respectively, for all P; 16 and 22 mm plaque results were more position-dependent. {sup 103}Pd produced a 16%-35% BED benefit over {sup 125}I, whereas {sup 131}Cs produced a 3%-7% BED detriment, independent of P, T, and plaque size. Additionally, corresponding organ at risk physical doses were lowest using {sup 103}Pd in all circumstances. Conclusions: The results suggest that shorter implant durations may correlate with more favorable outcomes compared to 7 day implants when treating small or medium intraocular lesions. The data also indicate that implant duration may be safely reduced if the prescription physical dose is likewise diminished and that {sup 103}Pd offers a substantial radiobiological benefit over {sup 125}I and {sup 131}Cs irrespective of plaque position, implant duration, and tumor size.« less
Evaluation of flow cytometric methods for determining population potential doubling times using cultured cells

Various methods have been proposed for determining the potential doubling times (Tpot) of mammalian cell populations by using flow cytometric techniques after labeling the cells with bromodeoxyuridine (BrdUrd). We show here that, in a well-defined in vitro system where multiple time measurements are possible, all the methods give similar results that are close to the true population doubling time. Of ultimate interest, however, is the accuracy of determination of Tpot from a single time point. In this paper we compare the accuracy and precision of the methods in making such determinations at different times after labeling. The relative movement (RM) of BrdUrd-labeled cells that have not divided at the time of assay allows for computation of the length of S phase (Ts). The precision of estimation of Ts was enhanced when a quantity, ν (a function of the fraction of BrdUrd-labeled divided and the fraction of BrdUrd-labeled undivided cells), was used to estimate the initial intercept of RM. Furthermore, calculation of Tpot from the formula, Tpot = ln(2) Ts/v, gave values closest to the observed population doubling time. It is suggested that the use of RM with v be the analytical method of choice for the calculation of Tpot from single time-point observations, preferably made at times between the length of the G2 and M phases (TG2M) and Ts.
Foods of the Gulf Sturgeon in the Suwannee River, Florida

Abstract Soft-bodied annelids, arthropods, and occasionally globular molluscs were primary foods of the threatened Gulf sturgeon Acipenser oxyrinchus desotoi collected from the mouth upriver to kilometer 221 of the Suwannee River, Florida, in 1988–1990. In spring, large subadults and adults that immigrated from the estuary had fed primarily on lancelets, brachiopods, amphipods and other crustaceans, polychaetes, and gastropods. Small Gulf sturgeons that remained near the mouth of the river during spring fed on epibenthic and hyperbenthic amphipods and grass shrimp and on isopods, oligochaetes, polychaetes, and chironomid and ceratopogonid larvae found in the intertidal zone, Subadults of more than 5 kg and adults in the freshwater middle river reaches between km 55 and 221 essentially fasted during the summer and fall. Gulf sturgeons in the Suwannee River were indifferent to abundant potential freshwater foods and apparently had stored sufficient nutrient reserves while in the estuary. A presumably young-...
Getting residents in the game: an evaluation of general surgery residents’ participation in pediatric laparoscopic surgery

Abstract Purpose In a large children’s hospital, the authors evaluated general surgery residents’ experience with pediatric laparoscopic procedures and the impact of their participation on patient outcome. Methods The records of all children who underwent laparoscopic appendectomy, splenectomy, fundoplication, or pyloromyotomy were reviewed. The level of participation by general surgery residents in each of these operations was determined. Outcome was assessed for these procedures in terms of intraoperative and postoperative complications. Results A resident was the operating surgeon in 164 of 174 laparoscopic appendectomies (94%), 37 of 38 laparoscopic splenectomies (97%), 78 of 104 laparoscopic fundoplications (75%), and 72 of 97 laparoscopic pyloromyotomies (74%). Adverse outcomes in the cases in which a resident was surgeon were limited to 4 postappendectomy infectious complications, 3 cases of recurrent reflux after fundoplication, and one incomplete myotomy and one mucosal injury after laparoscopic pyloromyotomy. Conclusions The authors have shown that well-supervised general surgery residents can perform common, pediatric laparoscopic operations with excellent results. Although it is essential for established pediatric surgeons and fellows in pediatric surgery to acquire expertise in minimally invasive surgery, once they have confidence in their own skills they may safely permit qualified general surgery residents to perform laparoscopic procedures in children.
Dimer-plus-chain structure for the SI(100)- c (4×2) surface

Proposition d'une nouvelle structure c(4×2) pour la surface Si(100) dans laquelle les atomes de la seconde couche sont dimerises et les atomes de la couche superieure forment des chaines a liaison π
The Comparative Histories of Slavery in Brazil, Cuba, and the United States

Introduction 1. From colonization to abolition: patterns of historical development in Brazil, Cuba, and the United States 2. The diversity of slavery in the Americas to 1790 3. Slaves in their own words 4. Slave populations 5. Economic aspects 6. Making space 7. Resistance and rebellions 8. Abolition Bibliography.
Scattering parameters measurement of a nonreciprocal coupling structure

A novel ferrite image guide was designed and tested from 26.5 to 40 GHz. The nonreciprocal structure consisted of two dielectric image guides separated by a ferrite slab. M-type hexagonal ferrite was used with its C-axis oriented parallel and perpendicular to the direction of propagation. The S-parameters of the device were measured for a nonuniform external biasing magnetic field applied parallel to the C-axis of the ferrite slab. Nonreciprocal effects were observed for all cases considered above. The results imply applications for ferrite devices operating at millimeter wavelength frequencies, such as isolators, filters, modulators, switches, phase shifters, etc. >