Miracle-dz/UniFAR-FTUs huggingface dataset:
Structural MRI Predictors of Late-Life Cognition Differ Across African Americans, Hispanics, and Whites.

BACKGROUND Structural magnetic resonance imaging (MRI) provides key biomarkers to predict onset and track progression of Alzheimer's disease (AD). However, most published reports of relationships between MRI variables and cognition in older adults include racially, ethnically, and socioeconomically homogenous samples. Racial/ethnic differences in MRI variables and cognitive performance, as well as health, socioeconomic status and psychological factors, raise the possibility that brain-behavior relationships may be stronger or weaker in different groups. The current study tested whether MRI predictors of cognition differ in African Americans and Hispanics, compared with non-Hispanic Whites. METHODS Participants were 638 non-demented older adults (29% non-Hispanic White, 36% African American, 35% Hispanic) in the Washington Heights-Inwood Columbia Aging Project. Composite scores of memory, language, speed/executive functioning, and visuospatial function were derived from a neuropsychological battery. Hippocampal volume, regional cortical thickness, infarcts, and white matter hyperintensity (WMH) volumes were quantified with FreeSurfer and in-house developed procedures. Multiple-group regression analysis, in which each cognitive composite score was regressed onto MRI variables, demographics, and cardiovascular health, tested which paths differed across groups. RESULTS Larger WMH volume was associated with worse language and speed/executive functioning among African Americans, but not among non-Hispanic Whites. Larger hippocampal volume was more strongly associated with better memory among non-Hispanic Whites compared with Hispanics. Cortical thickness and infarcts were similarly associated with cognition across groups. CONCLUSION The main finding of this study was that certain MRI predictors of cognition differed across racial/ethnic groups. These results highlight the critical need for more diverse samples in the study of cognitive aging, as the type and relation of neurobiological substrates of cognitive functioning may be different for different groups.
Patterns of bone mineral density testing

AbstractOBJECTIVES: To identify potential obstacles to bone mineral density (BMD) testing, we performed a structured review of current osteoporosis screening guidelines, studies of BMD testing patterns, and interventions to increase BMD testing. DESIGN: We searched medline and HealthSTAR from 1992 through 2002 using appropriate search terms. Two authors examined all retrieved articles, and relevant studies were reviewed with a structured data abstraction form. MEASUREMENTS AND MAIN RESULTS: A total of 235 articles were identified, and 51 met criteria for review: 24 practice guidelines, 22 studies of screening patterns, and 5 interventions designed to increase BMD rates. Of the practice guidelines, almost one half (47%) lacked a formal description of how they were developed, and recommendations for populations to screen varied widely. Screening frequencies among at-risk patients were low, ranging from 1% to 47%. Only eight studies assessed factors associated with BMD testing. Female patient gender, glucocorticoid dose, and rheumatologist care were positively associated with BMD testing; female physicians, rheumatologists, and physicians caring for more postmenopausal patients were more likely to test patients. Five articles described interventions to increase BMD testing rates, but only two tested for statistical significance and no firm conclusions can be drawn. CONCLUSIONS: This systematic review identified several possible contributors to suboptimal BMD testing rates. Osteoporosis screening guidelines lack uniformity in their development and content. While some patient and physician characteristics were found to be associated with BMD testing, few articles carefully assessed correlates of testing. Almost no interventions to improve BMD testing to screen for osteoporosis have been rigorously evaluated.
Relevance of postmortem radiology to the diagnosis of fatal cerebral gas embolism from compressed air diving

Aims: To test the hypothesis that artefact caused by postmortem off-gassing is at least partly responsible for the presence of gas within the vascular system and tissues of the cadaver following death associated with compressed air diving. Methods: Controlled experiment sacrificing sheep after a period of simulated diving in a hyperbaric chamber and carrying out sequential postmortem computed tomography (CT) on the cadavers. Results: All the subject sheep developed significant quantities of gas in the vascular system within 24 hours, as demonstrated by CT and necropsy, while the control animals did not. Conclusions: The presence of gas in the vascular system of human cadavers following diving associated fatalities is to be expected, and is not necessarily connected with gas embolism following pulmonary barotrauma, as has previously been claimed.
Isotope tracing enhancement of chemiluminescence assays for nitric oxide research

Abstract Chemiluminescence assays are used widely for the detection of nitric oxide (NO)-derived species in biological fluids and tissues. Here, we demonstrate that these assays can be interfaced with mass-sensitive detectors for parallel determination of isotopic abundance. Results obtained with tri-iodide and ascorbic acid-based reductive assays indicate that mass spectrometric detection enables NO isotope-tracing experiments to be carried out to a limit of detectability of a few picomoles, a sensitivity similar to that of standard gas phase chemiluminescence methods. The advantage afforded by mass spectrometric detection is demonstrated using the murine macrophage cell line J774, which is shown here to reduce 15NO3- to 15NO2- under anoxic conditions. The particular combination of an analytical and cellular system described here may hold promise for future characterization of the enzymatic pathways contributing to mammalian nitrate reductase activity, without background interference from 14NO2- derived from other sources.
Levels of nitric oxide metabolites in cerebrospinal fluid correlate with cognitive impairment in early stage multiple sclerosis

Cognitive impairment is an important clinical symptom of multiple sclerosis (MS) that often becomes an obstacle for employment, school attendance, and other activities of daily living and can occur in the early stage of disease, even in patients with clinically isolated syndrome or radiologically isolated syndrome.1 Recent studies have suggested both neuronal degeneration and central inflammation produce neuropathological damage to the central nervous system (CNS) in MS.2 Oxidative stress has been implicated in MS-related neurodegeneration.2 A previous study showed that nitrite and nitrate (NOx), which are oxidant metabolites of NO, are elevated in cerebrospinal fluid (CSF) from patients with MS.3 The excess production of NO may participate in MS-associated lesion formation and neuronal loss. In order to better elucidate the relationship between NOx and CNS damage in the early stage of MS, we investigated the relationship between cognitive impairment and CSF NOx levels in patients with early stage disease. We enrolled a total of 23 patients who were newly diagnosed with relapsing-remitting MS in accordance with the 2010 McDonald criteria.4 Participants were within 2 years of clinical onset and in remission for more than 3 months since the time of their most recent corticosteroid therapy or acute exacerbation. No patients were receiving disease modifying therapy at the time of CSF sample collection. We excluded patients who had other autoimmune disease …
Further results on fault detection and isolation of malicious nodes in Multi-hop Control Networks

A Multi-hop Control Network (MCN) consists of a LTI system where the communication between sensors, actuators and computational units is supported by a (wireless) multi-hop communication network and data flow is performed using scheduling, routing and network coding of sensing and actuation data. In this paper we extend our previous results in [6] on the Fault Detection and Isolation (FDI) problem over a MCN where the plant is a MIMO system and the communication nodes are subject to permanent failures and malicious attacks. In particular, we provide necessary and sufficient conditions such that the FDI problem can be solved with much milder assumptions on the malicious signal.
Effectiveness and efficiency of national systems of innovation: A comparative analysis of Ghana and Kenya

This paper presents a comparative analysis of the determinants of the effectiveness and efficiency of the Ghana National System of Innovation (GNSI) and the Kenya National System of Innovation (KNSI) for crafting evidence-based policy. Two regression analyses are performed respectively on the level of innovativeness of business enterprises (BEs) (effectiveness) and of the strength of linkages between research institutes (RIs) and the production system (efficiency) using an array of independent variables culled from the national systems of innovation (NSI) literature. We find first that the effectiveness of the GNSI and KNSI are positively associated with actor linkages in both, and diffusion and capacity of ICT with respect to Ghana; the efficiency of the GNSI and KNSI are positively related to diffusion and rate of access to ICT and negatively to lack of finance with respect to Ghana, while negatively associated with actor linkages – i.e. government and arbitraguer linkages – with respect to Kenya. In both countries the strength of RIs linkages with the production system is a significant determinant of NSI effectiveness; and the level of innovativeness of BEs is a significant determinant of NSI efficiency.
A model for measuring natural area values and park preferences

Theory suggests that values are important in determining an individual's behaviour and preferences related to environmental issues; however robust models that attempt to describe empirical relationships have proven elusive. This paper describes a model that clarified some relationships between values and preferences for the future management of natural areas. The key element in the model was the use of a new scale, the Natural Area Value Scale (NAVS) for measuring the relative strengths of individuals' intrinsic, non-use, use and recreation values for natural areas. Also of importance was a variable that grouped people according to their common values. The data were obtained from samples of the general public, environmentalists and farmers in Australia and were analysed in a structural equation model. The model indicated the relative importance of particular value components in determining nature conservation preferences, as well as individuals' willingness to make personal sacrifices to secure these preferences for protecting natural areas. The model fit differed for the three samples: it provided a good fit for the general public sample, for which it was designed, and weaker fit for environmentalists and farmers. The work contributes to understanding of the values that underlie conservation decisions and provides a basis for further research to develop the model's explanatory power.
Spiral interpolation algorithm for multislice spiral CT. I. Theory

This paper presents the adaptive axial interpolator (AAI), a novel spiral interpolation approach for multislice spiral computed tomography (CT) implemented in a clinical multislice CT scanner, the SOMATOM Volume Zoom (Siemens Medical Systems, Forchheim, Germany). The method works on parallel-beam data generated from the acquired fan-beam data by azimuthal rebinning. Spiral interpolation is performed by distance-dependent weighting; i.e., for each ray, its distance to the image plane is evaluated and serves as an argument to a freely selectable weighting function, resulting in a weight factor. A normalization step is applied to the weight factors to ensure that the sum of all corresponding weights (i.e., the weights applied to rays that contribute to the same ray in the interpolated sinogram) is 1. By selection of appropriate weighting functions and suitable adjustment of the tube current, it is possible to keep the slice sensitivity profiles (SSP) as well as the pixel noise constant for all pitch values in the relevant range. Also, a large range of slice-thickness can be reconstructed from a given collimation. The method is, thus, very versatile. Further advantages are that it uses the entire applied dose for imaging and allows for efficient implementation using a table lookup approach.
Positive effects of polyethylene glycol conjugation to generation‐4 polyamidoamine dendrimers as macromolecular MR contrast agents

Macromolecules conjugated with polyethylene glycol (PEG) acquire more hydrophilicity, resulting in a longer half‐life in circulation and lower immunogenicity. Two novel conjugates for MRI contrast agents were synthesized from a generation‐4 polyamidoamine dendrimer (G4D), 2‐(p‐isothiocyanatobenzyl)‐6‐methyl‐diethylenetriaminepentaacetic acid (1B4M), and one or two PEG molecules with a molecular weight of 20000 Da (PEG2‐G4D‐(1B4M‐Gd)62 (MW: 96 kD), PEG1‐G4D‐(1B4M‐Gd)63 (MW: 77 kD)). Their pharmacokinetics, excretion, and properties as vascular MRI contrast agents were evaluated and compared with those of G4D‐(1B4M‐Gd)64 (MW: 57 kD). PEG2‐G4D‐(1B4M‐Gd)62 remained in the blood significantly longer and accumulated significantly less in the liver and kidney than the other two preparations (P < 0.01). Although the blood clearance was slower, PEG2‐G4D‐(1B4M‐Gd)62 was excreted more readily without renal retention than the other two preparations. In conclusion, the positive effects of PEG conjugation on a macromolecular MRI contrast agent were found to be prolonged retention in the circulation, increased excretion, and decreased accumulation in the organs. Magn Reson Med 46:781–788, 2001. © 2001 Wiley‐Liss, Inc.
Mast cells in ongoing acute rejection: increase in number and expression of a different phenotype in rat heart transplants1

Background. Mast cells (MC) are resident in healthy hearts and play important physiological and pathophysiological roles. In the transplanted heart, correlations have been found between MC number and the severity of rejection episodes, the intensity of chronic inflammation, and allograft arteriosclerotic changes. However, not much emphasis has been placed on the fact that resident donor MC, and infiltrating recipient MC do not forcedly need to share the same properties and function. To gain insight in the role of cardiac MC during acute, and ongoing acute rejection of heart transplants, we investigated MC kinetics and MC phenotype in a rat heart transplantation model. Methods. Donor hearts from female Brown-Norway rats were transplanted to male Lewis rats. Immunosuppression was started at day 5 using ciclosporin and prednisolone. Connective tissue type MC (CTMC) were distinguished from mucosa type MC (MMC) by immunohistochemistry for rat MC protease (RMCP) -1 and -2. Expression of RMCP-1 and -2 mRNA was quantified by real time reverse transcription-polymerase chain reaction. Infiltrating Y chromosome positive MC were detected by fluorescence in situ hybridization. mRNA expression of interleukin-3 (IL-3) and of the two differentially spliced isoforms of kit ligand (KL, stem cell factor) was quantified using reverse transcription-polymerase chain reaction. Results. Resident cardiac donor MC are almost exclusively CTMC and decrease in number during acute rejection. MC increase in number, and recipient MC invade the cardiac allograft during ongoing acute rejection. The phenotype of the invading MC is characterized by the expression of RMCP-2, or both RMCP-1 and RMCP-2, and thus resemble a MMC type. IL-3 mRNA is highly expressed, and the ratio of the differentially spliced mRNAs for KL-1 and KL-2 rises up to 2-fold during ongoing acute rejection. Conclusions. Our data show that MC in posttransplant hearts during ongoing acute rejection differ from MC in healthy hearts and isografts by expressing a different phenotype. Changes in IL-3 and KL expression might be responsible for the predominance of MMC over CTMC. The notion is of importance that MC in cardiac allografts may have properties and functions that differ from those in nontransplanted healthy hearts.
Changing Roles of Traditional and Online Media as Trusted News Sources in Qatar and Their Relationships with Perceived Important Issues and Interest in Politics

This paper analyzes changes in media consumption patterns for trusted news sources over a three-year period among Qatari Nationals and expatriate residents living in Qatar, using data from the 2010, 2011, and 2012 Omnibus Surveys of Life in Qatar, administered by the Social and Economic Survey Research Institute (SESRI). Results show that television remains the strong favorite for local news and international news for both Qatari Nationals and expatriate residents, but that reliance on television is declining, especially for international news. Consumption of daily newspapers as the preferred source of local news remained stable among Qataris, but declined among expatriates. Internet news sites as the preferred source for local news increased during the three-year period. Additional analyses suggest weak agenda-setting effects between trusted news sources and perceived most important issues, and positive correlations between use of Internet sites and interest in political news.
The Role of Technology in Teaching and the Classroom

Although much in twenty-first century K-12 education still needs to be figured out, such as creating a generally-agreed-upon twenty-first century curriculum, one goal is, I think, now clear – the pedagogy with which our kids should be taught. Although it can be stated in many ways, the basic direction is away from the “old” pedagogy of teachers “telling” (or talking, or lecturing, or being the “Sage on the Stage”) to the “new” pedagogy of kids teaching themselves with teacher’s guidance (a combination of “student-centered learning,” “problem-based learning,” “case-based learning,” and the teacher’s being the “Guide on the Side.”)
Lactic threshold vs ventilatory threshold during a ramp test on a cycle ergometer.

OBJECTIVE The purpose of this investigation was to study the relationship between the lactate (LT) and the ventilatory threshold (VT) during a ramp protocol in cycle ergometry. PARTICIPANTS Thirty nine trained male subjects were selected as subjects. EXPERIMENTAL DESIGN All the subjects performed a maximal ergometric test on a cycle ergometer consisting of a ramp protocol (increases of 25 W.min-1). The anaerobic threshold (AT) was determined using both ventilatory gas analysis (VT) and lactate measurement (LT). All the data related to the VT and LT were expressed in work rate (W), VO2 (ml.kg-1.min-1) and heart rate (bpm) and expressed as mean and standard deviation. Lactate threshold (LT) and ventilatory threshold (VT) were compared using the Student's "t"-test for paired data. Correlation coefficients between both variables were also calculated. Statistical significance was accepted at the 5% level. RESULTS Results showed significant differences (p < 0.05) between mean values of VT and LT when both expressed either as heart rate (bpm), work rate (W), or VO2 (ml.kg-1.min-1). CONCLUSIONS It was concluded that LT and VT occur at different exercise intensities during ramp protocol exercise on a cycle ergometer.
Improved sensitivity of electrocochleography in the diagnosis of Meniere's disease

Abstract ECochG has long been shown to complement the diagnosis of MD, primarily through measurement of the SP/AP amplitude ratio. While reported in the literature to be highly specific to this disorder, ECochG's sensitivity in the general MD population remains relatively low (ranging from 20–65%). The current study assessed the sensitivity and specificity of the ECochG protocol we employ for suspected MD patients, which includes measuring both the amplitudes and areas of the SP and AP to clicks (to derive the SP/AP amplitude and area ratios), and the SP amplitudes to 1000 and 2000 Hz tone bursts. A retrospective chart review was conducted to compare ECochG results from 178 suspected MD patients with their eventual diagnoses. Measurements of highest sensitivity and specificity (determined using a logistic regression analysis) included: SP amplitude, SP area, SP/AP area ratio, and total SP-AP area. Sensitivity and specificity values associated with these measures were 92% and 84%, respectively. The sensitivity value is considerably higher than previously reported, and is attributable to the inclusion of area measurements in our protocol. Sumario La ECochG ha demostrado ser complementaria en el diagnóstico de la enfermedad de Meniere (MD) principalmente medi-ante la medición de la amplitud del ratio SP/AP. Mientras que se ha reportado en la literatura la alta especificidad de la ECochG, su sensibilidad en la población general con MD permanece relativamente baja (en un rango del 20 al 65%). Este estudio evalúa la sensibilidad y la especificidad del protocolo de ECochG que empleamos en pacientes con sospecha de MD, el cual incluye la medición tanto de la amplitud y las áreas de SP y AP con clics (para derivar los ratios de área y amplitud SP/AP), y las amplitudes de SP con burst tonales de 1000 y 2000Hz. Se construyó una tabla retrospectiva para comparar los resultados de ECochG de 178 pacientes con sospecha de MD, con sus diagnósticos eventuales. Las mediciones de la más alta sensibilidad y especificidad (determinadas mediante un análisis de regresión logística) incluyeron: amplitud SP, área SP, ratio de área SP/AP y área total SP-AP. La sensibilidad y la especificidad asociadas con estas mediciones fueron 92% y 84% respectivamente. El valor de sensibilidad es considerable-mente mayor que el previamente reportado y se atribuye a la inclusión de la medición del área en nuestro protocolo.
Reversal of Heterochromatic Silencing of Quiescent Herpes Simplex Virus Type 1 by ICP0

ABSTRACT Persisting latent herpes simplex virus genomes are to some degree found in a heterochromatic state, and this contributes to reduced gene expression resulting in quiescence. We used a relatively long-term quiescent infection model in human fibroblasts, followed by provision of ICP0 in trans, to determine the effects of ICP0 on the viral chromatin state as gene expression is reactivated. Expression of ICP0, even at low levels, results in a reduction of higher-order chromatin structure and heterochromatin on quiescent viral genomes, and this effect precedes an increase in transcription. Concurrent with transcriptional activation, high levels of ICP0 expression result in the reduction of the heterochromatin mark trimethylated H3K9, removal of histones H3 and H4 from the quiescent genome, and hyperacetylation of the remaining histones. In contrast, low levels of ICP0 did not appreciably change the levels of histones on the viral genome. These results indicate that ICP0 activity ultimately affects chromatin structure of quiescent genomes at multiple levels, including higher-order chromatin structure, histone modifications, and histone association. Additionally, the level of ICP0 expression affected its ability to change chromatin structure but not to reactivate gene expression. While these observations suggest that some of the effects on chromatin structure are possibly not direct, they also suggest that ICP0 exerts its effects through multiple mechanisms.