168 research outputs found

    Selection of non-regular fractional factorial designs when some two-factor interactions are important

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    Introduction: Non-regular two-level fractional factorial designs, such as Placket-Burman designs, are becoming popular choices in many areas of scientific investigation due to their run size economy and flexibility. The run size of non-regular two-level factorial designs is a multiple of 4. They fill the gaps left by the regular two-level fractional factorial designs whose run size is always a power of 2 (4, 8, 16, 32, ...). In non-regular factorial designs each main effect is partially confounded with all the two-factor interactions not involving itself. Because of this complex aliasing structure, non-regular factorial designs had not received sufficient attention until recently. ... In practical applications of non-regular designs, it is often in the case that some of the two-factor interactions are important and need to be estimated in addition to the main effects. In this article, we consider how to select non-regular two-level fractional factorial designs when some of the two-factor interactions are presumably important. We propose and study a method to select the optimal non-regular two-level fractional factorial designs in the situation that some of the two-factor interactions are potentially important. We then discuss how to search for the best designs according to this method and present some results for the Plackett-Burman design of 12 runs.Includes bibliographical references

    Optimal selection of blocked robust parameter designs and their applications

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    Blocking is a useful technique to control systematic variation in experiments. Robust parameter design is widely used as an effective tool to reduce process variability by appropriate selection of control factors to make the process insensitive to noise. In this paper, we propose and study a method for selecting the optimal blocked robust parameter designs when some of the control-by-noise interactions are included in the model. We then discuss how to search for the best designs according to this method and present some results for designs of 8 and 16 runs.Includes bibliographical references

    SELECTION OF BLOCKED TWO-LEVEL FRACTIONAL FACTORIAL DESIGNS FOR AGRICULTURAL EXPERIMENTS

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    Blocked two-level fractional factorial designs are a very useful tool for efficient data collection in agricultural and other scientific research. In most experiments, in addition to the main effects, some two-factor interactions are also meaningful and need to be estimated. We propose a method for efficiently selecting blocked two-level fractional factorial designs when some of the two-factor interactions are non-negligible. We then present some results for a design with only 8 or 16 runs to illustrate how to use this method

    Transition of Experienced and New Graduate Nurses to a Pediatric Hospital

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    This study reports on the 3-, 6-, 12-, and 18-month outcomes of 118 newly hired registered nurses (RNs) who completed a 12-month transition-to-practice program at a pediatric hospital. Experienced RNs (n = 42) and new graduate RNs (n = 76) showed improved organization, prioritization, communication, and leadership skills over time. The experienced RNs reported better communication and leadership skills than the new graduate nurses. Results inform transition program development for both new and experienced nurses. The American Association of Colleges of Nursing (2012) predicts that, without a multifaceted approach, a national nursing shortage will occur by 2020. Many nurses leave their first position and sometimes the profession within the first year of employment (Baxter, 2010; Welding, 2011). Retaining nurses is a vital component of any approach to averting a nursing shortage. In an attempt to retain nurses, healthcare institutions often provide a transition-to-practice (TTP) or nurse residency program for new graduate nurses (NGN) entering the profession. The Institute of Medicine (2011) in its Future of Nursing report also recommends a transition program for nurses moving to a new specialty or to advanced practice roles. Completing a NGN transition program is associated with a decrease in nurse attrition by as much as 80% (Halfer, Graf, & Sullivan, 2008; Rush, Adamack, Gordon, Lilly, & Janke, 2013; Spector et al., 2015). This reported decrease has led to organizational interest in transition programs to improve retention. The goals of residency programs for the NGN have ranged from increasing new nurse confidence and competence, to increasing satisfaction and retention (Fink, Krugman, Casey, & Goode, 2008; Goode, Lynn, McElroy, Bednash, & Murray, 2013; Institute of Medicine, 2011; Spector et al., 2015). Although literature supports the effectiveness of transition programs for the NGN (Fink et al., 2008; Goode et al., 2013; Spector et al., 2015), there is little evidence on the experienced nurse’s transition to a new specialty practice. Furthermore, most transition programs do not report outcomes beyond the first 12 months of employment. Thus, the purpose of this study is to evaluate nurse stressors and supports during and after a 12-month transition-to-employment program for both new and experienced nurses transitioning to a pediatric practice

    Hazard ratios of second primary malignancy after radioiodine for differentiated thyroid carcinoma: a large-cohort retrospective study

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    Introduction: The objective of this study is to evaluate the benefits of radioactive iodine (RAI) treatment and the risk of second primary malignancy (SPM) in RAI-treated patients. Material and methods: The cohort for this analysis consisted of individuals diagnosed with a first primary differentiated thyroid carcinoma (DTC), reported by the Surveillance, Epidemiology, and End Results (SEER) database in 1988–2016. Overall survival (OS) difference was estimated by Kaplan-Meier curves and log-rank test, and hazard ratios (HR) were obtained by Cox proportional-hazards model to evaluate the association between RAI and SPM. Results: Among 130,902 patients, 61,210 received RAI and 69,692 did not, and a total of 8604 patients developed SPM. We found that OS was significantly higher in patients who received RAI than in those who did not (p < 0.001). DTC survivors treated with RAI had increased risk of SPM in females (p = 0.043), particularly for SPM occurring in the ovary (p = 0.039) and leukaemia (p < 0.0001). The risk of developing SPM was higher in the RAI group than in the non-RAI group and the general population, and the incidence increased with age. Conclusions: Increased risk of SPM occurs in female DTC survivors treated with RAI, which become more obvious with increasing age. Our research findings were beneficial to the formulation of RAI treatment strategies and the prediction of SPM for patients with thyroid cancer of different genders and different ages

    A tale of two conditions: when people living with HIV meet three doses of inactivated COVID-19 vaccines

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    BackgroundCurrently, data on long-term immune responses to a homogenous booster dose of the inactivated COVID-19 vaccine are still limited among people living with HIV (PLWH).MethodsA prospective cohort study with a 13-month follow-up was conducted in China between March 2021 and August 2022 to evaluate the dynamics of SARS-CoV-2 specific humoral and cellular immunity against three doses of the inactivated COVID-19 vaccine from before the first dose until 6 months after the booster dose vaccination among PLWH in comparison to healthy controls (HC).Results43 PLWH on antiretroviral therapy (ART) and 23 HC were enrolled. Compared with HC, the neutralizing antibodies (nAbs) levels among PLWH were significantly lower on days 14, 30, 60, 90, and 120 after the booster dose vaccination. Among PLWH, the nAbs titers on days 14, 30, and 60 after the booster dose were significantly higher than the peak of the second dose. However, on day 180 after the booster dose, the nAbs titers were similar to the peak of the second dose vaccination. Compared with HC, the frequencies of IFN-γ-secreting and TNF-α-secreting CD4+ and CD8+ T cells among PLWH were lower on days 14 and 180 after the booster dose vaccination. Among PLWH, increased T cell immunity was induced by the booster dose of the vaccine and kept stable on day 180 after the booster dose vaccination.ConclusionAlthough a homogenous booster dose following two doses of the inactivated COVID-19 vaccine among PLWH could elicit higher nAb titers, reduce antibody decay, and maintain T cell responses even 6 months after vaccination, the overall immunogenicity of the booster dose was found to be lower among PLWH than among healthy controls. Further strategies are needed to improve immunogenicity to the inactivated COVID-19 vaccine among PLWH

    Advances in genetic factors of adolescent idiopathic scoliosis: a bibliometric analysis

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    ObjectiveThis study offers a bibliometric analysis of the current situation, hotspots, and cutting-edge domains of genetic factors of adolescent idiopathic scoliosis (AIS).MethodsAll publications related to genetic factors of AIS from January 1, 1992, to February 28, 2023, were searched from the Web of Science. CiteSpace software was employed for bibliometric analysis, collecting information about countries, institutions, authors, journals, and keywords of each article.ResultsA cumulative number of 308 articles have been ascertained. Since 2006, publications relating to genetic factors of AIS have significantly increased. China leads in both productivity and influence in this area, with the Chinese Academy of Medical Sciences being the most productive institution. The most prolific scholars in this field are Y. Qiu and Z. Z. Zhu. The publications that contributed the most were from Spine and European Spine Journal. The most prominent keywords in the genetic factors of AIS were “fibrillin gene”, “menarche”, “calmodulin”, “estrogen receptor gene”, “linkage analysis”, “disc degeneration”, “bone mineral density”, “melatonin signaling dysfunction”, “collagen gene”, “mesenchymal stem cell”, “LBX1”, “promoter polymorphism”, “Bone formation”, “cerebrospinal fluid flow” and “extracellular matrix”.ConclusionThis analysis provides the frontiers and trends of genetic factors in AIS, including relevant research, partners, institutions and countries

    Six-month humoral immune response to inactivated COVID-19 vaccine among people living with HIV

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    Longitudinal humoral immune response to inactivated COVID-19 vaccines among people living with HIV (PLWH) have not yet been systematically investigated. We conducted a 6-month longitudinal study among vaccinated PLWH and HIV-Negative Controls (HNC) to determine whether the humoral immune response effects of the inactivated COVID-19 vaccine are different between the two groups of people. Totally, 46 PLWH and 38 HNC who received the inactivated COVID-19 vaccine on days 0 and 28 were enrolled. The SARS-CoV-2 neutralizing antibodies (nAbs) and total specific IgM and IgG antibodies were examined on Day 0-Day190. The level and positive seroconversion rate of nAbs peaked on Day 42 in HNC while peaked on Day 70 in PLWH, then decreased gradually with the extension of the vaccination period after the peaks. The peak level of nAbs in PLWH on Day 70, (GMC 8.07 BAU/mL, 95% CI 5.67-11.48) was significantly lower than in HNC on Day 42 (GMC 18.28 BAU/mL, 95% CI 10.33-32.33, P =0.03). The decrease in the geometric mean concentrations (GMCs) of nAbs was observed as 42.9% in PLWH after peak level, which decreased from 8.07 BAU/mL [95% CI: 5.67-11.48] on Day 70 to 4.61 BAU/mL [95% CI: 3.35-6.34] on Day 190 (p = 0.02). On Day 190, only seven (18%, [95% CI: 6-40]) HNC and five (11%, [95% CI: 4-25]) PLWH maintained positive nAbs response respectively. The geometric mean ELISA units (GMEUs) and positive seroconversion rate of IgG in PLWH dropped significantly from Day 70 (GMEUs, 0.20 EU/mL, [95% CI: 0.13-0.34]; seroconversion, 52%, [95% CI: 34-69]) to Day 190 (GMEUs, 0.05 EU/mL, [95% CI: 0.03-0.08], P<0.001; seroconversion, 18%, [95% CI: 8-33], P<0.001). There was no significant difference in levels and seroconversion rates of nAbs and IgG between the two groups on Day 190. The peak immunogenicity of the inactivated COVID-19 vaccine was delayed and inferior in PLWH compared to HNC, while no significant difference was found in six-month immunogenicity between the two groups

    A tale of two conditions: when people living with HIV meet three doses of inactivated COVID-19 vaccines

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    Background Currently, data on long-term immune responses to a homogenous booster dose of the inactivated COVID-19 vaccine are still limited among people living with HIV (PLWH). Methods A prospective cohort study with a 13-month follow-up was conducted in China between March 2021 and August 2022 to evaluate the dynamics of SARS-CoV-2 specific humoral and cellular immunity against three doses of the inactivated COVID-19 vaccine from before the first dose until 6 months after the booster dose vaccination among PLWH in comparison to healthy controls (HC). Results 43 PLWH on antiretroviral therapy (ART) and 23 HC were enrolled. Compared with HC, the neutralizing antibodies (nAbs) levels among PLWH were significantly lower on days 14, 30, 60, 90, and 120 after the booster dose vaccination. Among PLWH, the nAbs titers on days 14, 30, and 60 after the booster dose were significantly higher than the peak of the second dose. However, on day 180 after the booster dose, the nAbs titers were similar to the peak of the second dose vaccination. Compared with HC, the frequencies of IFN-γ-secreting and TNF-α-secreting CD4+ and CD8+ T cells among PLWH were lower on days 14 and 180 after the booster dose vaccination. Among PLWH, increased T cell immunity was induced by the booster dose of the vaccine and kept stable on day 180 after the booster dose vaccination. Conclusion Although a homogenous booster dose following two doses of the inactivated COVID-19 vaccine among PLWH could elicit higher nAb titers, reduce antibody decay, and maintain T cell responses even 6 months after vaccination, the overall immunogenicity of the booster dose was found to be lower among PLWH than among healthy controls. Further strategies are needed to improve immunogenicity to the inactivated COVID-19 vaccine among PLWH
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