scholarly journals Reproducibility of QuantiFERON-TB Gold In-Tube Assay

2008 ◽  
Vol 15 (3) ◽  
pp. 425-432 ◽  
Author(s):  
Sharon Perry ◽  
Luz Sanchez ◽  
Shufang Yang ◽  
Zubin Agarwal ◽  
Philip Hurst ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Interferon Response ◽  
Foreign Born ◽  
Transient Responses ◽  
Time Points ◽  
Baseline Visit ◽  
Conversion Rates ◽  
Targeted Screening ◽  
Positive Results

ABSTRACT Studies are needed to characterize the reproducibility of QuantiFERON-TB Gold (QFT-G) for targeted U.S. screening populations. Members of northern California households were tested with the QFT-G in-tube assay (QFT-G-IT) at two home visits 3 months apart. Reproducibility and agreement with the tuberculin skin test (TST) were assessed. Monte Carlo simulation was used to evaluate the role of test-related error. Of 63 individuals (49 adults and 14 children) completing QFT-G-IT at both time points, 79% were foreign-born (98% from Latin America) and 68% reported Mycobacterium bovis BCG vaccination. At the baseline visit, 23 (37%) were TST positive and 15 (24%) were QFT-G-IT positive (κ = 0.48 [± 0.11]). At 3 months, 3/48 (6.3%; 95% confidence interval [95CI], 2 to 17) of those initially QFT-G-IT negative converted, and 5/15 (33%; 95CI, 15 to 58) of those initially QFT-G-IT positive reverted. Among the 8 individuals with inconsistent QFT-G-IT results, the maximum gamma interferon response at either visit was 0.68 IU/ml versus means of 4.99 (± 3.74) and 6.95 (± 5.6) for 10 persistent positives at the first and second visits, respectively. Expected false-reversion and -conversion rates were 32% (90CI, 25 to 39%) and 6.95% (90CI, 4.6 to 9.8%) when the sensitivity and specificity were assumed to average 70% and 98%, respectively. Transient responses to QFT-G-IT are common, and low positive results need to be interpreted with caution. Further studies are needed to characterize the predictive value of the test for U.S. foreign-born and other targeted screening populations.

scholarly journals The Role of La2O3 in Enhancement the Radiation Shielding Efficiency of the Tellurite Glasses: Monte-Carlo Simulation and Theoretical Study

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3913
Author(s):  
Aljawhara H. Almuqrin ◽  
Mohamed Hanfi ◽  
K. G. Mahmoud ◽  
M. I. Sayyed ◽  
Hanan Al-Ghamdi ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Theoretical Study ◽  
Radiation Shielding ◽  
Photon Flux ◽  
Transmission Factor ◽  
Tellurite Glasses ◽  
Attenuation Coefficients ◽  
Binary Glass ◽  
Buildup Factors

The radiation shielding competence was examined for a binary glass system xLa2O3 + (1 − x) TeO2 where x = 5, 7, 10, 15, and 20 mol% using MCNP-5 code. The linear attenuation coefficients (LACs) of the glasses were evaluated, and it was found that LT20 glass has the greatest LAC, while LT5 had the least LAC. The transmission factor (TF) of the glasses was evaluated against thicknesses at various selected energies and was observed to greatly decrease with increasing thickness; for example, at 1.332 MeV, the TF of the LT5 glass decreased from 0.76 to 0.25 as the thickness increased from 1 to 5 cm. The equivalent atomic number (Zeq) of the glasses gradually increased with increasing photon energy above 0.1 MeV, with the maximum values observed at around 1 MeV. The buildup factors were determined to evaluate the accumulation of photon flux, and it was found that the maximum values for both can be seen at around 0.8 MeV. This research concluded that LT20 has the greatest potential in radiation shielding applications out of the investigated glasses due to the glass having the most desirable parameters.

Acculturation and Subsequent Oral Health Problems Among Foreign-Born Older Chinese Americans: Does Neighborhood Disorder Matter?

2021 ◽  
pp. 016402752110187
Author(s):  
Weiyu Mao ◽  
Bei Wu ◽  
Iris Chi ◽  
Wei Yang ◽  
XinQi Dong
Keyword(s):  
Oral Health ◽  
Chinese Americans ◽  
Health Problems ◽  
Community Dwelling ◽  
Neighborhood Disorder ◽  
Foreign Born ◽  
Lagged Dependent Variable ◽  
Older Chinese ◽  
Older Chinese Americans

Objectives: To investigate the relationship between acculturation and subsequent oral health problems in older Chinese Americans and to further test the moderating role of neighborhood disorder in such a relationship. Methods: The working sample included 2,706 foreign-born community-dwelling older Chinese Americans aged 60 years or older who participated in the Population Study of Chinese Elderly in Chicago at baseline between 2011 and 2013 and the 2-year follow-up between 2013 and 2015. Stepwise Poisson regressions with lagged dependent variable were conducted. Results: Behavioral acculturation was protective against subsequent oral health problems, and the protective role was stronger among individuals reporting lower levels of neighborhood disorder. Residence in Chinatown was associated with an increase in the risk of subsequent oral health problems. Discussion: To reduce oral health symptoms and related burdens, it is important to consider, in practice and policy, the role of acculturation and the neighborhood on subsequent oral health outcomes.

scholarly journals Model-based evaluation of school- and non-school-related measures to control the COVID-19 pandemic

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ganna Rozhnova ◽  
Christiaan H. van Dorp ◽  
Patricia Bruijning-Verhagen ◽  
Martin C. J. Bootsma ◽  
Janneke H. H. M. van de Wijgert ◽  
...  
Keyword(s):  
Reproduction Number ◽  
Additional Benefit ◽  
Transmission Model ◽  
Time Points ◽  
School Based ◽  
Admission Data ◽  
Age Structured ◽  
The Impact ◽  
Pandemic Wave

AbstractThe role of school-based contacts in the epidemiology of SARS-CoV-2 is incompletely understood. We use an age-structured transmission model fitted to age-specific seroprevalence and hospital admission data to assess the effects of school-based measures at different time points during the COVID-19 pandemic in the Netherlands. Our analyses suggest that the impact of measures reducing school-based contacts depends on the remaining opportunities to reduce non-school-based contacts. If opportunities to reduce the effective reproduction number (Re) with non-school-based measures are exhausted or undesired and Re is still close to 1, the additional benefit of school-based measures may be considerable, particularly among older school children. As two examples, we demonstrate that keeping schools closed after the summer holidays in 2020, in the absence of other measures, would not have prevented the second pandemic wave in autumn 2020 but closing schools in November 2020 could have reduced Re below 1, with unchanged non-school-based contacts.

Characteristics of educators’ talk about decontextualised events

2020 ◽  
Vol 45 (4) ◽  
pp. 362-376
Author(s):  
Rebecca Andrews ◽  
Penny Van Bergen
Keyword(s):  
Communication Skills ◽  
Future Event ◽  
Time Points ◽  
Long Day ◽  
Future Events ◽  
Day Care Centres ◽  
Highly Correlated ◽  
Children’S Thinking ◽  
Sydney Australia

This study investigated the characteristics of educators’ talk about decontextualised events with young children in seven early childhood long day care centres in Sydney, Australia. Educators were partnered with up to six children aged between 27 and 60 months. Across two time points, 85 educator–child dyads discussed past and future events. Educators’ use of questions, contextual statements, evaluations and prompts and children’s use of questions, open-ended responses, yes-no responses and spontaneous information statements were examined. Educators’ evaluative statements were highly correlated and educators’ questions were moderately correlated with children’s open-ended responses in past event conversations. Educators’ evaluative statements were highly correlated with children’s open-ended responses in future event conversations and were the only significant predictor for children’s talk. Given the important role of educators in scaffolding children’s thinking and communication skills, the recommended strategies for educators’ talk in decontextualised conversations include: sharing the conversational load, making frequent contextual statements and following the child’s lead/interests.

Double-Balloon Enteroscopy in Detecting Small-Bowel Neuroendocrine Neoplasms: A Single-Center Prospective Study

Digestion ◽  
2020 ◽  
pp. 1-9
Author(s):  
Roberta Elisa Rossi ◽  
Luca Elli ◽  
Federica Branchi ◽  
Dario Conte ◽  
Sara Massironi
Keyword(s):  
Small Bowel ◽  
Neuroendocrine Neoplasm ◽  
Unknown Primary ◽  
Neuroendocrine Neoplasms ◽  
Double Balloon Enteroscopy ◽  
Balloon Enteroscopy ◽  
Double Balloon ◽  
Diagnostic Role ◽  
Positive Results

<b><i>Background and Aim:</i></b> Small-bowel neuroendocrine neoplasm (sbNEN) diagnosis has improved with double-balloon enteroscopy (DBE). DBE efficacy in the detection of sbNENs is unknown. We aimed to report the experience at a single referral center for NENs. <b><i>Methods:</i></b> All consecutive patients with a suspected sbNEN selected for diagnostic DBE were enrolled. <b><i>Results:</i></b> Between 2011 and 2016, 25 patients were referred for a suspected sbNEN. In 15/25 patients, a primary NEN was detected outside the small bowel; in 4, NEN was excluded. After extensive workup, 6 patients (4 males, median age 50 years) underwent DBE (3 anterograde, 2 retrograde, and 1 both; median time: 60 min; median insertion 200 cm). DBE was positive in 3 patients: one had an ileal 2-cm NEN G1, one had an ileal 1.3-cm NEN G1, and one had an ileal 1-cm NEN G2, all surgically removed. Of the 3 other patients, one had a metastatic NEN of unknown primary, the other two had small intestinal NENs, both surgically removed (1.6-cm G1 and G2 NEN). DBE showed a sensitivity of 60% and, in absence of false-positive results, a specificity of 100%. Accuracy resulted 67%. No complications were observed. <b><i>Conclusions:</i></b> In line with data from the literature, the present series showed that DBE is a safe and effective procedure in the diagnosis of sbNENs. Further studies are needed to better clarify the diagnostic role of DBE in the neuroendocrine tumor setting and its relationship with other techniques.

scholarly journals COVID-19 Shuts Doors to Flu but Keeps Them Open to Rhinoviruses

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 733
Author(s):  
Irina Kiseleva ◽  
Andrey Ksenafontov
Keyword(s):  
Influenza Pandemic ◽  
Age Groups ◽  
Influenza Viruses ◽  
Interferon Response ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Mild Disease ◽  
Viral Interference ◽  
The Common

It is well known that rhinoviruses are distributed across the globe and are the most common cause of the common cold in all age groups. Rhinoviruses are widely considered to be harmless because they are generally perceived as respiratory viruses only capable of causing mild disease. However, they may also infect the lower respiratory tract, inducing chronic obstructive pulmonary disease and exacerbations of asthma, bronchiolitis, etc. The role of rhinoviruses in pathogenesis and the epidemiological process is underestimated, and they need to be intensively studied. In the light of recent data, it is now known that rhinoviruses could be one of the key epidemiological barriers that may influence the spread of influenza and novel coronaviruses. It has been reported that endemic human rhinoviruses delayed the development of the H1N1pdm09 influenza pandemic through viral interference. Moreover, human rhinoviruses have been suggested to block SARS-CoV-2 replication in the airways by triggering an interferon response. In this review, we summarized the main biological characteristics of genetically distinct viruses such as rhinoviruses, influenza viruses, and SARS-CoV-2 in an attempt to illuminate their main discrepancies and similarities. We hope that this comparative analysis will help us to better understand in which direction research in this area should move.

Role of MR venography in the evaluation of deep venous thrombosis

1997 ◽  
Vol 38 (5) ◽  
pp. 907-912 ◽  
Author(s):  
C. Catalano ◽  
P. Pavone ◽  
A. Laghi ◽  
A. Scipioni ◽  
F. Fanelli ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Deep Venous Thrombosis ◽  
Sensitivity And Specificity ◽  
Filling Defect ◽  
Clinical Suspicion ◽  
Mr Venography ◽  
Diagnostic Modalities ◽  
Positive Results ◽  
Intraluminal Filling Defect

Purpose: MR venography has been recommended for the evaluation of deep venous thrombosis. The purpose of our study was to determine the role of MR venography, in particular at the level of the pelvis where other diagnostic modalities show major limitations. Materials and Methods: Forty-three patients with clinical suspicion of deep venous thrombosis were examined by means of pelvic MR venography. In all cases, a 2D-TOF sequence was used with cranial arterial presaturation. In selected cases, i.e. when a small intraluminal filling defect was present, a cine-PC sequence was used in addition in order to exclude the presence of a pulsatility artifact as causing the filling defect. In all cases, contrast venography was also performed and considered to be the standard of reference. Results: MR venography showed 26 patients to be positive for deep venous thrombosis at the pelvic level. These positive results were correct in 25 cases. The analysis of the results provided values of sensitivity and specificity of respectively 100% and 94%, with an overall accuracy of 97.6%. Conclusion: Our results indicate that MR can provide highly accurate images, similar to those of contrast venography, in a noninvasive fashion. It is particularly useful in the pelvic region where the limitations of other imaging modalities are more evident.

نماذج المحاكاة- محاكاة مونتي كارلو- كأسلوب كمي من أساليب النمذجة واتخاذ القرارات - مقاربة نظرية وتطبيقية

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
محمد الأمين ◽  
بن حامد عبد الغني ◽  
مراس محمد
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Quantitative Methods ◽  
Practical Importance ◽  
Investment Project ◽  
Simulation Method ◽  
Period Analysis ◽  
Investment Projects ◽  
Monte Carlo Simulation Model

Our research aims to try to present the modeling mechanisms in the field of simulation and quantitative methods. The research is a presentation of the role of quantitative methods in making investment project evaluation decisions, more than that and is the use of the Monte Carlo simulation model in evaluation and multi-period analysis of investment projects under conditions Risk and uncertainty. And highlighting the theoretical, scientific and practical importance of the Monte Carlo simulation method in particular, and the importance of using quantitative methods in helping to make decisions in general

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