Miracle-dz/UniFAR-FTUs huggingface dataset:
Improvement in Early Oxygen Uptake Kinetics With Left Ventricular Assist Device Support

Sustained myocardial recovery and reversal of heart failure has been reported with the use of left ventricular assist devices (LVADs). However, clinical predictors of sustained recovery have not been clearly defined, and little information exists regarding exercise improvement in LVAD patients. Therefore, we sought to determine whether peripheral oxygen delivery and utilization were improved with LVAD support. Eleven patients with available pre- and post-LVAD cardiopulmonary exercise (CPX) data were studied retrospectively. Five patients received a HeartMate XVE for destination therapy (DT) and six patients received a Thoratec PVAD pneumatic LVAD for bridge-to-recovery (BTR). Oxygen uptake kinetics was assessed by fitting a single exponential function to the VO2 response. There was a significant improvement in several key parameters of cardiac performance including peak VO2, VO2 at anaerobic threshold (AT), oxygen kinetics as measured by mean response time (MRT), and oxygen deficit during LVAD support. Oxygen deficiency improved from 0.29 ± 0.16 ml/kg to 0.16 ± 0.06 ml/kg (p = 0.023), as did MRT 68 ± 47.7 seconds to 35.8 ± 13.3 seconds (p = 0.046) with LVAD support. Improved oxygen kinetics suggests improved peripheral utilization of oxygen, and may offer an additional clinical parameter to predict the likelihood of sustained recovery.
Determinants of Web site implementation in small businesses

Founded on IT diffusion and assimilation theory, a survey study of 54 Canadian travel agencies has allowed us to identify various factors determining the assimilation of electronic commerce by small enterprises in the form of informational, transactional, and strategic implementation of a Web site. The results indicate that informational implementation and transactional implementation are determined by the environmental context (business partners’ influence and environmental uncertainty), whereas strategic implementation is determined by the travel agencies’ marketing strategy (in terms of distribution and communication), the organizational context (type of ownership, nature of business), and the characteristics of electronic commerce (perceived advantages and technology attributes).
Performance evaluation of a robotically controlled millimeter-wave near-field pattern range at the NIST

The Antenna Metrology Laboratory at the National Institute of Standards and Technology (NIST) is developing a robotically controlled near-field pattern range for measuring antennas and components from 50 GHz to 500 GHz. This new range is intended to address the need for accurate antenna pattern measurements for a variety of applications including remote sensing and imaging. This system incorporates a precision industrial six-axes robot, six-axes parallel kinematic hexapod, and high precision rotation stage. A laser tracker is used to determine position and to calibrate the robot. The robotic positioning arm is programmable and allows scanning in a variety of geometries including spherical, planar, cylindrical, and perform in-situ extrapolation measurements, as well as, other user defined geometries. For the planar geometry, the coverage is a rectangle 1.25 m × 2 m. For spherical, radii from 2 cm to 2 m are possible, while the coverage in θ is ±120° and in φ is ±180°. Robot positioning repeatability has been evaluated and determined to be about 30 μm, and absolute positioning determination via the laser tracker is ~15 μm. Specifics regarding the range evaluation are presented.
H2 optimal model order reduction by two-sided technique on Grassmann manifold via the cross-gramian of bilinear systems

ABSTRACT In this paper, we discuss the optimal H2 model order reduction (MOR) problem for bilinear systems. The H2 optimal MOR problem of bilinear systems is considered as the minimisation problem on Grassmann manifold, which is stored as a quotient space of the noncompact Stifiel manifold. Grassmann manifold whose tangent space is endowed with a Riemannian metric is a Riemannian manifold. In its tangent space equipped with the Riemannian metric, we derive the negative gradients of the cost function, i.e. the steepest descent direction of the cost function. After that, the formulas of geodesic on Grassmann manifold are given. Then we perform linear searches along geodesics to obtain the optimal solutions. Thereby, a two-sided MOR iterative algorithm is proposed to construct an order-reduced bilinear system, which is used to simulate the output and input responses of the original bilinear system. Numerical examples demonstrate the effectiveness of our algorithm.
Model selection for incomplete and design‐based samples

The Akaike information criterion, AIC, is one of the most frequently used methods to select one or a few good, optimal regression models from a set of candidate models. In case the sample is incomplete, the naive use of this criterion on the so‐called complete cases can lead to the selection of poor or inappropriate models. A similar problem occurs when a sample based on a design with unequal selection probabilities, is treated as a simple random sample. In this paper, we consider a modification of AIC, based on reweighing the sample in analogy with the weighted Horvitz–Thompson estimates. It is shown that this weighted AIC‐criterion provides better model choices for both incomplete and design‐based samples. The use of the weighted AIC‐criterion is illustrated on data from the Belgian Health Interview Survey, which motivated this research. Simulations show its performance in a variety of settings. Copyright © 2006 John Wiley & Sons, Ltd.
Glaucoma In Vivo Lamina Cribrosa MicroArchitecture in Healthy and Glaucomatous Eyes as Assessed by Optical Coherence Tomography

Department of Ophthalmology, UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts Department of Computer Science, University of Erlangen-Nuremberg, Nuremberg, Germany
Theoretical and experimental study of the optical-absorption spectrum of exciton resonance in In0.53Ga0.47As/InP quantum wells.

This paper presents a theoretical formulation of the integrated intensity and the profile of the optical-absorption spectrum of exciton resonance in quantum wells. Using our model, we analyzed the ground-state electron\char21{}heavy-hole exciton resonance in 20-period multiple quantum wells with 10-nm ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As wells and 10-nm InP barriers. We found the intrinsic integrated intensity in this quantum well to be 1.1\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}4}$ eV, which was about 70% of that in GaAs/${\mathrm{Al}}_{0.25}$${\mathrm{Ga}}_{0.75}$As quantum wells reported by Masselink. We demonstrate quantitatively that the smaller integrated intensity is due to the larger two-dimensional exciton radius caused by the larger static dielectric constant and the smaller in-plane reduced effective mass. We propose that the resonance spectrum profile should be formed by the convolution integral between the broadening function due to the spatial inhomogeneity of exciton energy and that due to the reduction of exciton lifetime by thermal phonon scattering. Inhomogeneous broadening was found to be a Gaussian distribution from the measured low-temperature spectrum. Assuming that the LO phonon is the major scattering source for excitons and that the distribution function of their lifetime is Lorentzian with a width of half the average, we could explain the measured profile of exciton resonance up to high temperatures. We found the average exciton lifetime to be 300 fs at room temperature. We argue that inhomogeneous broadening due to composition fluctuations in ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As wells and the larger thermal broadening due to the larger exciton-phonon coupling make the exciton spectrum broader than GaAs/${\mathrm{Al}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Ga}}_{\mathit{x}}$As quantum wells. We conclude that both the smaller integrated intensity and the broader spectrum make the exciton resonance in ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As/InP quantum wells weaker. We present the condition of inhomogeneous broadening needed to observe exciton resonance at room temperature.
Extracellular glucose concentrations in the brain.

To the Editors: In a recent article in thisJournal, McNay and Gold (1999) reported that the concentration of the glucose in the hippocampal extracellular fluid (ECF) of awake, freely moving rats is on the order of 1.0–1.2 m M, across strain and age groups. In our opinion, to consider these low glucose values as absolute and physiological leaves several questions open. Indeed, classical models of glucose transport suggest a brain ECF concentration of 2 m M (Lund-Andersen, 1979), in line with the estimated brain concentrations of 2–4 mmol g (Mason et al., 1992) and with the brain ECF glucose concentrations on the order of 2–3 m M found in anesthetized animals by several different methodologies (Silver and Erecin ́ska, 1994; Ronne Engstro ̈m et al., 1995; Hu and Wilson, 1997), including the chronically implanted tissue cages (Sechi et al., 1991). Our results from five measurements by this latter method showed that the brain extracellular glucose concentration, in steady-state conditions, was 2.7 6 0.2 mM (mean 6 SEM, n 5 5) in normoglycemic dogs (4.7 6 0.2 mM in plasma) under pentobarbital anesthesia. Taken together, these data indicate an estimated brain ECF glucose concentration, in anesthetized animals, across strain, and different methodologies of 2.6 m M (weighted mean of the mean values of ECF glucose concentrations reported in the four articles quoted previously). A rough correction of this value for interfering factors, such as pentobarbital anesthesia ( 212.5%) (Gjedde and Rasmussen, 1980) and neuronal activation (225%) (McNay and Gold, 1997), gives an indicative brain ECF glucose concentration, in freely moving animals, of 1.6 mM, which is higher than those found by McNay and Gold (1999). An enhanced glucose metabolism following the implantation of a probe (Benveniste et al., 1987), mainly evident in freely moving animals, and perhaps an interference of the implanted probe on glucose transport at the glial/neuronal surface might partly explain the low brain ECF glucose levels found by McNay and Gold (1999).
Resonance Raman scattering of cytochrome P450 BM3 and effect of imidazole inhibitors.

Resonance Raman scattering from cytochrome P450 BM3 is obtained with a Raman microprobe using 406-nm excitation with an accumulation time of a few seconds. The small sample size and rapid measurement time make the routine characterization of P450 systems by resonance Raman spectroscopy easier. Addition of imidazole and imidazole derivatives as inhibitors causes the appearance of additional peaks due to vinyl modes, increases the relative intensity of symmetric modes that would be A(1g) in D(4h) symmetry, and causes a large drop in the intensity of nu(11). This information indicates that the ligation of imidazoles to the heme iron causes the alignment of the vinyl modes with the plane of the heme ring and reduces the out of plane distortion of the ring. The effect of both inhibitors is similar but there is a subtle difference in the extent of the reduction in the intensity of nu(11), which suggests that steric effects within the pocket are having some effect.
Isolation, characterization, and physiological role of the pyruvate dehydrogenase complex and alpha-acetolactate synthase of Lactococcus lactis subsp. lactis bv. diacetylactis

The pyruvate dehydrogenase complex of Lactococcus lactis subsp. lactis bv. diacetylactis has a specific activity of 6.6 U/mg and a Km of 1 mM for pyruvate. The specific activities of E2 and E3 in the complex are 30 and 0.36 U/mg, respectively. The complex is very sensitive to NADH inhibition and consists of four subunits: E1 alpha (44 kDa), E1 beta (35 kDa), E2 (73 kDa), and E3 (60 kDa). The L. lactis alpha-acetolactate synthase has a specific activity of 103 U/mg and a Km of 50 mM for pyruvate. Thiamine pyrophosphate (Km = 3.2 microM) and divalent cations are essential for activity. The native enzyme measures 172 kDa and consists of 62-kDa monomers. The role of both enzymes in product formation is discussed in view of NADH inhibition and competition for pyruvate.
Amyloid-&bgr; E22Δ variant induces synaptic alteration in mouse hippocampal slices

We recently identified a novel amyloid precursor protein mutation (E693Δ) in familial Alzheimer's-type dementia. This mutation produces amyloid-&bgr; (A&bgr;) variant lacking glutamate-22 (E22Δ), which showed enhanced oligomerization but no fibrillization. Here, we examined in-vitro toxicity of A&bgr; E22Δ peptide. Wild-type A&bgr;1-42 showed a dose-dependent (1 nM to 1 μM) cytotoxicity to cultured neuronal cells in the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide assay, whereas A&bgr;1-42 E22Δ was toxic only weakly at 1 μM. In mouse hippocampal slices, however, A&bgr;1-42 E22Δ caused a dose-dependent (0.1–10 μM) decrease of synaptophysin, whereas wild-type A&bgr;1-42 was trophic at 0.1–1 μM and toxic at 10 μM. These results suggest that extracellular A&bgr; E22Δ causes more potent synaptic alteration, but lower neurodegeneration, than wild-type A&bgr; probably because of its unique aggregation property.
The web learning system of 'Virtual eBMS': a tool supporting unstructured and just-in-time learning

In the era of the Global, Digital and Knowledge-based Economy, a just-in-time access to learning content, as well as an efficient way to access increasingly distributed knowledge sources, is required in order to solve the problem of 'knowledge obsolescence'. In this scenario, traditional web learning systems are no longer adequate and need a strong integration with Knowledge Management (KM) systems, in order to trigger just-in-time/at workplace/customised/on-demand and unstructured learning processes, in place of an old-fashioned time/place/content predefined ones. In this paper, we describe the main pillars underpinning an innovative approach to web learning based on the above-mentioned principles. Moreover, we provide a detailed representation of the web learning component of 'Virtual eBMS', a web-based system designed and implemented at the e-Business Management Section of the Scuola Superiore ISUFI, University of Salento (Italy). In particular, we describe the content-oriented and the service-oriented perspectives of the implemented system by highlighting its innovative elements with respect to a traditional web learning system.
The relationship between hodological and cytoarchitectonic organization in the vestibular complex of the 11‐day chicken embryo

To understand the relationship between structure and function in specific brain regions, it is necessary to ascertain which anatomical features are physiologically relevant. Physiological studies of brain function traditionally have been set in the context of anatomical features based on cytoarchitectonics and myeloarchitectonics, but the relationship between structure and function in this context can be complex. Alternative schemes of anatomical organization, such as that based on hodology (the mapping of projections) may provide greater insight. Here, we make a direct comparison of the hodological and the cytoarchitectonic organization of the vestibular complex in the mid‐term chicken embryo, using retrograde tracing and three‐dimensional reconstruction. In one set of experiments, vestibulospinal and vestibulo‐ocular neuron groups were selectively labeled with biotin dextran‐amines and aligned with the cytoarchitectonically defined vestibular nuclei in alternating sections that were then combined into intercalated three‐dimensional models. This allowed a semiquantitative analysis of the apportionment of individual hodological groups among cytoarchitectonic nuclei. In another set of experiments, vestibulospinal and vestibulo‐ocular neuron groups were labeled differentially with fluorescent dextran‐amines, three‐dimensionally reconstructed, and subjected to a quantitative analysis of spatial overlap. Our results provide the first three‐dimensional representation and quantitative analysis of the hodological compartmentalization of the vestibular complex (the “hodological mosaic”). They also show directly how each hodologically defined neuron group relates to the conventional vestibular nuclei, underscoring the fact that the units of the hodological mosaic do not bear a one‐to‐one correspondence to the cytoarchitectonic nuclear divisions. Some hodologically defined groups are localized to restricted portions of a nucleus, whereas others overlap multiple nuclei. Thus, hodology and cytoarchitectonic features appear to be separately regulated in the vestibular complex of the chicken embryo, possibly through different sets of positional specification mechanisms. The three‐dimensional representations we present here provide a foundation for integrating anatomical, physiological, developmental, and evolutionary studies of the vestibular system. J. Comp. Neurol. 457:87–105, 2003. © 2003 Wiley‐Liss, Inc.
Dapagliflozin treatment in patients with different stages of type 2 diabetes mellitus: effects on glycaemic control and body weight

Aim: Dapagliflozin is a stable, competitive, reversible, and highly selective inhibitor of sodium‐glucose co‐transporter 2, the major transporter responsible for renal glucose reabsorption. With an insulin‐independent mechanism of action, dapagliflozin is currently being developed for the treatment of type 2 diabetes mellitus (T2DM). This work aims to compare the efficacy of dapagliflozin, as measured by the change in hemoglobin A1c concentration (A1c) and body weight, and to determine the pharmacodynamic effects of dapagliflozin, as measured by urinary glucose excretion in early‐stage and late‐stage T2DM patient populations.
Molecular mimicry of carbohydrate and protein structures by hybridoma antibodies

A large proportion of tumour‐associated antigens seem to be determined by carbohydrate structures. Advances in the study of the antigenicity of cell‐surface carbohydrates have been hampered by the absence of advanced monoclonal hybridoma technology comparable to that available for the study of protein antigens. Monoclonal antibodies have been raised against a carbohydrate epitope (43–9F) that is associated with the proliferative features of squamous lung carcinomas. These were used in turn to generate anti‐idiotype antibodies with homology to 43–9F. The method and its possible applications are described, together with a procedure to detect rare cell membrane variants within large populations.
Micrometer-sized thread-like and/or spherical particles in the first fraction of cerebrospinal fluid in patients with bipolar disorder.

OBJECTIVES Scanning electron microscopy (SEM) is a powerful tool to identify pathogenic factors for which sensitive tests are lacking. The technique has been used to recognize structures in the cerebrospinal fluid (CSF) of patients with schizophrenia. The aim of this study was to use SEM to screen for potential particles in CSF in bipolar disorder. METHODS Fresh CSF samples from 56 euthymic bipolar patients, 31 bipolar I disorder and 25 bipolar II disorder, were compared to CSF samples from 20 controls. SEM of two portions of 200 microL filtered CSF was performed; the first 0.6 mL of CSF and the following 12 mL. The microscopic structures were identified and the quantity and patterns were rated by two independent researchers. RESULTS Quantitative SEM examinations showed that of the 56 patients, 11 were free of any SEM structures in CSF, while 45 patients displayed morphological structures in the first 0.6 mL of CSF. By contrast, only 2 patients showed structures in the second CSF fraction drawn from the following mixed 12 mL of CSF. In total, 45 of the 56 patients had either thread-like, spherical, or both structures in the CSF, compared to none of the 20 controls. CONCLUSIONS The identified particles in the first fraction of CSF have previously not been described in patients with bipolar disorder. Hypothetically, the amount of SEM structures in CSF, from none to many, might correlate to the degree of the alleged underlying disease processes in the central nervous system in patients with bipolar disease.
Work Site Change and Psychosocial Well-Being among Health Care Personnel in Geriatric Wards—Effects of an Intervention Program

The study evaluated the effect of a change of work site and organization on work environment and psychosocial parameters; the change involved health care personnel at a geriatric hospital. Another aim of this study was to evaluate the effects of a structured psychoeducational intervention program. The study found few changes in the indices of interest on the experimental and control wards. There were, however, significant improvements in social climate, goal quality, and independence of work on the control ward. The investigators postulated that too much external support hampers a group's ability to actively cope with change and might actually lower a group's ability and self-esteem. In order to achieve successful organizational change, psychosocial intervention programs for personnel must be performed by a well-informed, well-chosen, and experienced counsellor who is well tailored to the local organization.
The Role of the Coach in Facilitating Positive Youth Development: Moving from Theory to Practice

Sport is suggested as a potentially important and sufficient path for positive youth development. However, how this responsibility is translated by coaching practitioners is not understood. This research investigated whether coaching practitioners desire outcomes for their adolescent athletes that reach beyond on-field success, and incorporate constructs that are associated with positive youth development. Twenty-two participation coaches for adolescent athletes participated in semi-structured interviews. Results suggest that coaches see themselves as responsible for facilitating eight interrelated and interdependent themes that are consistent with the positive youth development literature: competence, confidence, connection, character, life skills, climate, positive affect and, positive psychological capacities.
Molecular mechanisms for the conversion of zymogens to active proteolytic enzymes

Proteolytic enzymes are synthesized as inactive precursors, or “zymogens,” to prevent unwanted protein degradation, and to enable spatial and temporal regulation of proteolytic activity. Upon sorting or appropriate compartmentalization, zymogen conversion to the active enzyme typically involves limited proteolysis and removal of an “activation segment. ” The sizes of activation segments range from dipeptide units to independently folding domains comprising more than 100 residues. A common form of the activation segment is an N‐terminal extension of the mature enzyme, or “prosegment,” that sterically blocks the active site, and thereby prevents binding of substrates. In addition to their inhibitory role, prosegments are frequently important for the folding, stability, and/or intracellular sorting of the zymogen. The mechanisms of conversion to active enzymes are diverse in nature, ranging from enzymatic or nonenzymatic cofactors that trigger activation, to a simple change in pH that results in conversion by an autocatalytic mechanism. Recent X‐ray crystallographic studies of zymogens and comparisons with their active counterparts have identified the structural changes that accompany conversion. This review will focus upon the structural basis for inhibition by activation segments, as well as the molecular events that lead to the conversion of zymogens to active enzymes.