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This study examined how filters and amplifiers affect pre-service science teachers' pedagogical content knowledge (PCK) in a human and environment unit. The redefined consensus model for PCK and decision-making framework for identifying how personal and extrapersonal factors act as filters and amplifiers were selected as theoretical frameworks. Two pre-service science teachers participated in the study. While pre-interviews were used to determine participants' PCK before teaching, observations and post-interviews were used to reveal participants' PCK after teaching, and how filters and amplifiers influenced PCK. Data were analyzed deductively to examine teachers' PCK including interactions among components and the way filters and amplifiers act on PCK. Constant comparison analysis revealed five general assertions of how filters and amplifiers shaped the decision-making process when these teachers enacted their PCK. First, the number of amplifiers and filters affecting knowledge of instructional strategies (KOIS) was the highest. Second, the number of amplifiers and filters affecting knowledge of curriculum in science was the lowest. Third, the effect of filters and amplifiers on PCK components was idiosyncratic. Fourth, the more (or the less) the map was integrated; the less (or the more) amplifier and filter influenced the PCK. Fifth, the number of personal factors affecting KOIS was highest. Implications are suggested considering the effects of filters and amplifiers on teachers' PCK.

This study addresses suggestions for analyzing science teachers' pedagogical content knowledge (PCK) components and their interactions and these suggestions are expected to facilitate the analysis of science teachers' PCK, resulting in more accurate representations of PCK. Knowledge of the science curriculum, knowledge of students' understanding of science, knowledge of assessment in science, and knowledge of instructional strategies were used as specific PCK components in this study and the PCK mapping approach was used as the theoretical framework. Suggestions for PCK components' analysis are based on the similarity among PCK components and the similarity between PCK components and other knowledge domains. Furthermore, suggestions for the analysis of interaction among PCK components are related to the direction of interaction, the strength of one interaction considering its content, and categorizing the number of interactions between PCK components. These suggestions can provide new insights into the analysis of PCK components and their interactions for researchers and improve the precision and heuristic power of PCK models.

BACKGROUND: Low back pain (LBP) is a common public health problem resulting in workforce loss. OBJECTIVE: This study aims to evaluate the LBP status and its affecting factors among drivers in a city in southeast Turkey. METHODS: This cross-sectional questionnaire survey study was conducted among 323 drivers. The chi-square test and logistic regression analysis were used to analyze the data. RESULTS: The mean age of the drivers was 41.7±11.5 years (min: 19, max: 70), and 83.9% were married, and all were men. LBP was found in 59.4% of drivers. It was significantly higher in drivers with poor socioeconomic status, dissatisfied with their life, having a chronic illness, physically inactive, having sleep disorders, exposed to bad road conditions, prolonged vibration, high physical- psychological workload, and a family history of LBP (p < 0.05). There was no significant association between age, education level, and BMI with LBP (p > 0.05). CONCLUSION: There is limited study on this subject in Turkey. Further studies can raise awareness about this issue and create an educational plan. [ABSTRACT FROM AUTHOR]

Tumor hypoxia is an adverse prognostic factor in head and neck squamous cell carcinoma (HNSCC). We assessed whether patients with hypoxic HNSCC benefited from the addition of nimorazole to definitive intensity modulated radiation therapy (IMRT). NIMRAD was a phase 3, multicenter, placebo-controlled, double-anonymized trial of patients with HNSCC unsuitable for concurrent platinum chemotherapy or cetuximab with definitive IMRT (NCT01950689). Patients were randomized 1:1 to receive IMRT (65 Gy in 30 fractions over 6 weeks) plus nimorazole (1.2 g/m2 daily, before IMRT) or placebo. The primary endpoint was freedom from locoregional progression (FFLRP) in patients with hypoxic tumors, defined as greater than or equal to the median tumor hypoxia score of the first 50 patients analyzed (≥0.079), using a validated 26-gene signature. The planned sample size was 340 patients, allowing for signature generation in 85% and an assumed hazard ratio (HR) of 0.50 for nimorazole effectiveness in the hypoxic group and requiring 66 locoregional failures to have 80% power in a 2-tail log-rank test at the 5% significance level. Three hundred thirty-eight patients were randomized by 19 centers in the United Kingdom from May 2014 to May 2019, with a median follow-up of 3.1 years (95% CI, 2.9-3.4). Hypoxia scores were available for 286 (85%). The median patient age was 73 years (range, 44-88; IQR, 70-76). There were 36 (25.9%) locoregional failures in the hypoxic group, in which nimorazole + IMRT did not improve FFLRP (adjusted HR, 0.72; 95% CI, 0.36-1.44; P =.35) or overall survival (adjusted HR, 0.96; 95% CI, 0.53-1.72; P =.88) compared with placebo + IMRT. Similarly, nimorazole + IMRT did not improve FFLRP or overall survival in the whole population. In total (N = 338), 73% of patients allocated nimorazole adhered to the drug for ≥50% of IMRT fractions. Nimorazole + IMRT caused more acute nausea compared with placebo + IMRT (Common Terminology Criteria for Adverse Events version 4.0 G1+2: 56.6% vs 42.4%, G3: 10.1% vs 5.3%, respectively; P <.05). Addition of the hypoxia modifier nimorazole to IMRT for locally advanced HNSCC in older and less fit patients did not improve locoregional control or survival. [ABSTRACT FROM AUTHOR]

Background: Low back pain (LBP) is a common public health problem resulting in workforce loss., Objective: This study aims to evaluate the LBP status and its affecting factors among drivers in a city in southeast Turkey., Methods: This cross-sectional questionnaire survey study was conducted among 323 drivers. The chi-square test and logistic regression analysis were used to analyze the data., Results: The mean age of the drivers was 41.7±11.5 years (min: 19, max: 70), and 83.9% were married, and all were men. LBP was found in 59.4% of drivers. It was significantly higher in drivers with poor socioeconomic status, dissatisfied with their life, having a chronic illness, physically inactive, having sleep disorders, exposed to bad road conditions, prolonged vibration, high physical- psychological workload, and a family history of LBP (p < 0.05). There was no significant association between age, education level, and BMI with LBP (p > 0.05)., Conclusion: There is limited study on this subject in Turkey. Further studies can raise awareness about this issue and create an educational plan.

Integrin αIIbβ3 is the key receptor regulating platelet retraction and accumulation, thus pivotal for hemostasis, and arterial thrombosis as well as a proven drug-target for antithrombotic therapies. Here we resolve the cryoEM structures of the intact full-length αIIbβ3, which covers three distinct states along the activation pathway. Here, we resolve intact αIIbβ3 structure at 3Å resolution, revealing the overall topology of the heterodimer with the transmembrane (TM) helices and the head region ligand-binding domain tucked in a specific angle proximity to the TM region. In response to the addition of an Mn 2+ agonist, we resolved two coexisting states, "intermediate" and "pre-active". Our structures show conformational changes of the intact αIIbβ3 activating trajectory, as well as a unique twisting of the lower integrin legs representing intermediate state (TM region at a twisting conformation) integrin and a coexisting pre-active state (bent and opening in leg), which is required for inducing the transitioning platelets to accumulate. Our structure provides for the first time direct structural evidence for the lower legs' involvement in full-length integrin activation mechanisms. Additionally, our structure offers a new strategy to target the αIIbβ3 lower leg allosterically instead of modulating the affinity of the αIIbβ3 head region.