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In the United States, the Superpave Asphalt Binder Performance Grading (PG) system proposed by the Strategic Highway Research Program (SHRP) is the most common method used to characterize the performance-related properties of unmodified and polymer-modified asphalt binders. Dynamic shear modulus (G*) and phase angle (δ) are the two main binder properties and they are measured using a dynamic shear rheometer (DSR) with parallel plate geometry and either a 1-mm or 2-mm gap between the plates. Since these Superpave parameters were developed for binders that do not contain additives or particulates, the California Department of Transportation (Caltrans) does not use them for asphalt rubber binder specifications. Instead, penetration and viscosity are used as acceptance of quality control; however, these parameters do not necessarily provide a satisfactory link between the measured binder properties and potential performance in the field over a range of operating temperatures. In California, current specifications require that crumb rubber particles used to produce asphalt rubber binder in the “wet process” must be smaller than 2.36 mm (i.e., 100 percent passing the #8 sieve), and typically these particles vary in size between 1 mm and 2 mm. Consequently, when the parallel plate geometry is used to test this type of binder, the larger incompletely digested rubber particles can contact the plates. If this occurs, the rubber particle rheology can potentially dominate the results, which in turn may not be representative of the modified binder as a whole. To address this problem, a potentially more appropriate DSR testing protocol using concentric cylinder geometry was investigated in Phase 1 of this study to explore an alternative means of determining the performance properties of asphalt rubber binders. Phase 2 of the study, documented in this report, continued the investigation into the use of the concentric cylinder geometry and alternate parallel plate geometry with a 3-mm gap. The use of these geometries for intermediate-temperature testing and multiple stress creep recovery testing was also investigated, along with modified procedures for short- and long-term aging in the rolling thin-film oven and pressurized aging vessel, respectively, and specimen preparation procedures for bending beam rheometer (BBR) testing. Limited mix testing was also conducted to relate high- and low-temperature mix performance to the performance grades determined for the binders used in the mixes. The concentric cylinder testing approach to measuring the rheological properties of asphalt rubber binders is considered feasible, and that with its use, the edge effects and trimming issues associated with parallel plate testing can be eliminated. However, the concentric cylinder method requires a longer testing time and a larger binder sample than the parallel plate test method. Initial findings from performance grading and related mix testing indicate that the incompletely digested rubber particles, which have different sensitivities to temperature and applied stress and strain than the asphalt binder, appear to dominate the test results. This will need to be factored into analyses and interpretation of rheology and mix performance test results. The proposed modifications to the short- and long-term aging procedures and to the BBR specimen preparation procedures are considered to be more aligned with the original intent of the tests and will likely reduce the variability between replicate specimens during testing. The results from Phase 2 support the continuation of testing, which should be in line with the original workplan and objectives of this research effort. The research should continue to refine the testing procedures on additional field binder sources, assess the repeatability and reproducibility of any proposed test methods, and evaluate the applicability of the results to the actual performance properties of mixes produced with asphalt rubber binders.

In the United States, the Superpave Asphalt Binder Performance Grading (PG) system proposed by the Strategic Highway Research Program (SHRP) is the most common method used to characterize the performance-related properties of unmodified and polymer-modified asphalt binders. Dynamic shear modulus (G*) and phase angle (δ) are the two main binder properties and they are measured using a dynamic shear rheometer (DSR) with parallel plate geometry and either a 1-mm or 2-mm gap between the plates. Since these Superpave parameters were developed for binders that do not contain additives or particulates, the California Department of Transportation (Caltrans) does not use them for asphalt rubber binder specifications. Instead, penetration and viscosity are used as acceptance of quality control; however, these parameters do not necessarily provide a satisfactory link between the measured binder properties and potential performance in the field over a range of operating temperatures. In California, current specifications require that crumb rubber particles used to produce asphalt rubber binder in the “wet process” must be smaller than 2.36 mm (i.e., 100 percent passing the #8 sieve), and typically these particles vary in size between 1 mm and 2 mm. Consequently, when the parallel plate geometry is used to test this type of binder, the larger incompletely digested rubber particles can contact the plates. If this occurs, the rubber particle rheology can potentially dominate the results, which in turn may not be representative of the modified binder as a whole. To address this problem, a potentially more appropriate DSR testing protocol using concentric cylinder geometry was investigated in Phase 1 of this study to explore an alternative means of determining the performance properties of asphalt rubber binders. Phase 2 of the study, documented in this report, continued the investigation into the use of the concentric cylinder geometry and alternate parallel plate geometry with a 3-mm gap. The use of these geometries for intermediate-temperature testing and multiple stress creep recovery testing was also investigated, along with modified procedures for short- and long-term aging in the rolling thin-film oven and pressurized aging vessel, respectively, and specimen preparation procedures for bending beam rheometer (BBR) testing. Limited mix testing was also conducted to relate high- and low-temperature mix performance to the performance grades determined for the binders used in the mixes. The concentric cylinder testing approach to measuring the rheological properties of asphalt rubber binders is considered feasible, and that with its use, the edge effects and trimming issues associated with parallel plate testing can be eliminated. However, the concentric cylinder method requires a longer testing time and a larger binder sample than the parallel plate test method. Initial findings from performance grading and related mix testing indicate that the incompletely digested rubber particles, which have different sensitivities to temperature and applied stress and strain than the asphalt binder, appear to dominate the test results. This will need to be factored into analyses and interpretation of rheology and mix performance test results. The proposed modifications to the short- and long-term aging procedures and to the BBR specimen preparation procedures are considered to be more aligned with the original intent of the tests and will likely reduce the variability between replicate specimens during testing. The results from Phase 2 support the continuation of testing, which should be in line with the original workplan and objectives of this research effort. The research should continue to refine the testing procedures on additional field binder sources, assess the repeatability and reproducibility of any proposed test methods, and evaluate the applicability of the results to the actual performance properties of mixes produced with asphalt rubber binders.

Objective: To examine the renoprotective effects of metabolic surgery in patients with established chronic kidney disease (CKD). Background: The impact of metabolic surgery compared with glucagon-like peptide-1 receptor agonists (GLP-1RA) in patients with established CKD has not been fully characterized. Methods: Patients with obesity (body mass index =30 kg/m²), type 2 diabetes, and baseline estimated glomerular filtration rate (eGFR) 20-60 mL/min/1.73 m² who underwent metabolic bariatric surgery at a large US health system (2010-2017) were compared with nonsurgical patients who continuously received GLP-1RA. The primary end point was CKD progression, defined as a decline of eGFR by =50% or to <15 mL/min/1.73 m2, initiation of dialysis, or kidney transplant. The secondary end point was the incident kidney failure (eGFR <15 mL/min/1.73 m2, dialysis, or kidney transplant) or all-cause mortality. Results: 425 patients, including 183 patients in the metabolic surgery group and 242 patients in the GLP-1RA group, with a median follow-up of 5.8 years (IQR, 4.4-7.6), were analyzed. The cumulative incidence of the primary end point at 8 years was 21.7% (95% CI: 12.2-30.6) in the surgical group and 45.1% (95% CI: 27.7 to 58.4) in the nonsurgical group, with an adjusted hazard ratio of 0.40 (95% CI: 0.21 to 0.76), P=0.006. The cumulative incidence of the secondary composite end point at 8 years was 24.0% (95% CI: 14.1 to 33.2) in the surgical group and 43.8% (95% CI: 28.1 to 56.1) in the nonsurgical group, with an adjusted HR of 0.56 (95% CI: 0.31 to 0.99), P= 0.048. Conclusions: Among patients with type 2 diabetes, obesity, and established CKD, metabolic surgery, compared with GLP-1RA, was significantly associated with a 60% lower risk of progression of kidney impairment and a 44% lower risk of kidney failure or death. Metabolic surgery should be considered as a therapeutic option for patients with CKD and obesity. [ABSTRACT FROM AUTHOR]

We investigated the oncogenic role of SETDB1, focusing on non-small cell lung cancer (NSCLC), which has high expression of this protein. A total of 387 lung cancer cases were examined by immunohistochemistry; 72% of NSCLC samples were positive for SETDB1 staining, compared to 46% samples of normal bronchial epithelium (106 cases) (p

BackgroundRibonucleotide reductase catalyzes the conversion of ribonucleotide diphosphates to deoxyribonucleotide diphosphates. The functional enzyme consists of two subunits - one large (RRM1) and one small (RRM2 or RRM2b) subunit. Expression levels of each subunit have been implicated in prognostic outcomes in several different types of cancers.Experimental designImmunohistochemistry for RRM1 and RRM2 was performed on a lung cancer tissue microarray (TMA) and analyzed. 326 patients from the microarray were included in this study.ResultsIn non-small cell lung cancer (NSCLC), RRM2 expression was strongly predictive of disease-specific survival in women, non-smokers and former smokers who had quit at least 10 years prior to being diagnosed with lung cancer. Higher expression was associated with worse survival. This was not the case for men, current smokers and those who had stopped smoking for shorter periods of time. RRM1 was not predictive of survival outcomes in any subset of the patient group.ConclusionRRM2, but not RRM1, is a useful predictor of survival outcome in certain subsets of NSCLC patients.

Abstract Background Tissue microarray (TMA) data are commonly used to validate the prognostic accuracy of tumor markers. For example, breast cancer TMA data have led to the identification of several promising prognostic markers of survival time. Several studies have shown that TMA data can also be used to cluster patients into clinically distinct groups. Here we use breast cancer TMA data to cluster patients into distinct prognostic groups. Methods We apply weighted correlation network analysis (WGCNA) to TMA data consisting of 26 putative tumor biomarkers measured on 82 breast cancer patients. Based on this analysis we identify three groups of patients with low (5.4%), moderate (22%) and high (50%) mortality rates, respectively. We then develop a simple threshold rule using a subset of three markers (p53, Na-KATPase-β1, and TGF β receptor II) that can approximately define these mortality groups. We compare the results of this correlation network analysis with results from a standard Cox regression analysis. Results We find that the rule-based grouping variable (referred to as WGCNA*) is an independent predictor of survival time. While WGCNA* is based on protein measurements (TMA data), it validated in two independent Affymetrix microarray gene expression data (which measure mRNA abundance). We find that the WGCNA patient groups differed by 35% from mortality groups defined by a more conventional stepwise Cox regression analysis approach. Conclusions We show that correlation network methods, which are primarily used to analyze the relationships between gene products, are also useful for analyzing the relationships between patients and for defining distinct patient groups based on TMA data. We identify a rule based on three tumor markers for predicting breast cancer survival outcomes.

Abstract Background The protein AGR2 is a putative member of the protein disulfide isomerase family and was first identified as a homolog of the Xenopus laevis gene XAG-2. AGR2 has been implicated in a number of human cancers. In particular, AGR2 has previously been found to be one of several genes that encode secreted proteins showing increased expression in prostate cancer cells compared to normal prostatic epithelium. Methods Gene expression levels of AGR2 were examined in prostate cancer cells by microarray analysis. We further examined the relationship of AGR2 protein expression to histopathology and prostate cancer outcome on a population basis using tissue microarray technology. Results At the RNA and protein level, there was an increase in AGR2 expression in adenocarcinoma of the prostate compared to morphologically normal prostatic glandular epithelium. Using a tissue microarray, this enhanced AGR2 expression was seen as early as premalignant PIN lesions. Interestingly, within adenocarcinoma samples, there was a slight trend toward lower levels of AGR2 with increasing Gleason score. Consistent with this, relatively lower levels of AGR2 were highly predictive of disease recurrence in patients who had originally presented with high-stage primary prostate cancer (P = 0.009). Conclusions We have shown for the first time that despite an increase in AGR2 expression in prostate cancer compared to non-malignant cells, relatively lower levels of AGR2 are highly predictive of disease recurrence following radical prostatectomy.

Language teacher immunity, as a new notion in language teacher psychology, is a strong indicator of how teachers behave when dealing with difficulties and challenges; and it has a profound effect on teachers' careers. Research on language teacher immunity is in its nascent stage. This study employed an explanatory sequential mixed-methods design to explore the changes in EFL teachers' immunity for a semester in the COVID-19 era. In so doing, the language teacher immunity questionnaire (Language Immunity Questionnaire; Hiver [2016. Tracing the Signature Dynamics of L2 Teacher Immunity: A Retrodictive Qualitative Modeling Study." Unpublished Ph.D. thesis, University of Nottingham, England]) was administered to 30 male and female Iranian EFL teachers using SHAD application (an Iranian application developed to address the emergency remote teaching need to be created by the COVID-19 crisis) in the beginning, middle, and at the end of the Fall semester 2020. After that, follow-up interview data were collected to help explain the results of the quantitative phase. The results of the repeated-measures ANOVA indicated that there were differing changes in different aspects of participants' immunity. The follow-up qualitative data analysis showed that the changes in teachers' immunity were mainly due to familiarity with online teaching, scepticism of online learning, and limited student participation. The implications for future research in the field are discussed. [ABSTRACT FROM AUTHOR]

Structural equation modeling (SEM) is a statistical method used for testing and estimating causal relations using a combination of statistical data and qualitative causal assumptions. This paper reports two studies done by the researchers through the application of SEM. In the first study the relationship between EFL learners' affective constructs and their English achievement was assessed using SEM. Since both Structural coefficient and Goodness of fit are high, we conclude that not only is the model accepted but also the relationship between EFL learners' affective constructs and their English achievement is statistically significant. The second study investigated the relationship between Affective constructs and Study Process of EFL learners through the application of SEM. In this study the Goodness of Fit Index (GFI) turned out to be 0.99. Again like the previous study, since the Goodness of Fit Index (GFI) and structural coefficient are high, we conclude that there is a statistically strong relationship between affective constructs and study process of EFL learners.

Language teachers often encourage L2 readers to guess the meaning of unknown words in texts. This paper argues that before any statements about the value of guessing can be made, it is necessary to show how reliable learners' guesses are. To this end, the present study investigates how accurately EFL learners assess their understanding of unknown words, and whether language proficiency and gender influence their self-assessment. The study was carried out in three phases. In phase one, participants (N = 110) took a proficiency test and were asked to study a text in which 40 items were highlighted by the researcher on the basis of words that were unfamiliar to them. They were required to assess their understanding of the meaning of unknown words on a four-point scale. In phase two, they provided a translation, synonym, antonym, or an explanation of the unknown words. In phase three, they received the same self-assessment sheet to reassess their understanding of unknown words. The results indicated that learners' assessments are not reliable. Moreover, it was found that proficiency in the L2 and gender influence learners' self-assessment. (Contains 6 tables.)