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OBJECTIVE: Try to create a dose gradient function (DGF) and test its effectiveness in reducing radiation induced lung injury in breast cancer radiotherapy. MATERIALS AND METHODS: Radiotherapy plans of 30 patients after breast-conserving surgery were included in the study. The dose gradient function was defined as DGH=VDVp3, then the area under the DGF curve of each plan was calculated in rectangular coordinate system, and the minimum area was used as the trigger factor, and other plans were triggered to optimize for area reduction. The dosimetric parameters of target area and organs at risk in 30 cases before and after re-optimization were compared. RESULTS: On the premise of ensuring that the target dose met the clinical requirements, the trigger factor obtained based on DGF could further reduce the V5, V10, V20, V30 and mean lung dose (MLD) of the ipsilateral lung in breast cancer radiotherapy, Pâ<â0.01. And the D2cc and mean heart dose (MHD) of the heart were also reduced, Pâ<â0.01. Besides, the NTCPs of the ipsilateral lung and the heart were also reduced, Pâ<â0.01. CONCLUSION: The trigger factor obtained based on DGF is efficient in reducing radiation induced lung injury in breast cancer radiotherapy.
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Neoplasias da Mama , Lesão Pulmonar , Lesões por Radiação , Radioterapia de Intensidade Modulada , Humanos , Feminino , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias da Mama/radioterapia , Pulmão , Lesões por Radiação/prevenção & controleRESUMO
This study aims to develop a trigger operator based on the Overlap Volume Histogram (OVH) and examined its effectiveness in enhancing plan quality to minimize radiation-induced lung injury in postoperative radiotherapy for breast cancer. This trigger operator was applied for plan re-optimization to the previous Volumetric Modulated Arc Therapy (VMAT) plans of 16 left breast conserving surgery cases. These cases were categorized into a Contiguous Group (CG) and a Separated Group (SG) based on the relative position between the target and the Left-Lung (L-Lung). We investigated the changes in Vx, mean dose, and Normal Tissue Complication Probability (NTCP) values of organs-at-risk (OARs) before and after using the trigger operator. The Pairwise Sample T test was employed to evaluate the differences in indices between the two groups before and after optimizations. The trigger operator effectively initiated plan re-optimization. The values of V5, V10, V20, V30, and V40 of the L-Lung, as well as the mean dose of the heart, all decreased after re-optimization. The Pairwise Sample T test results showed statistically significant differences in the V20, V30, and V40 of the L-Lung in the CG (P < 0.01), and in the V5, V10, V20, V30, and V40 of the L-Lung in the SG (P < 0.01). Our findings suggest that the proposed trigger operator can improve plan quality, thereby reducing radiation-induced lung injury in postoperative radiotherapy for breast cancer.
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Neoplasias da Mama , Lesão Pulmonar , Lesões por Radiação , Radioterapia de Intensidade Modulada , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Pulmão , Órgãos em Risco , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controleRESUMO
Based on the career construction model of adaptation, this study explores the impact of core self-evaluations on career adaptability, with the mediating role of protean career attitudes and moderating role of meritocratic beliefs. The results of the questionnaire survey on 1000 Chinese college students show that: (1) core self-evaluations positively predicted college students' career adaptability; (2) protean career attitudes mediated the relationship between core self-evaluations and career adaptability; (3) meritocratic beliefs not only moderated the effect protean career attitudes have on career adaptability but also moderated the indirect influence of core self-evaluations on career adaptability through protean career attitudes. These results extend the existing antecedent studies on career adaptability and demonstrate the importance of combining self-mobility beliefs (protean career attitudes) with social mobility beliefs (meritocratic beliefs) in the process of core self-evaluations affecting career adaptability. In conclusion, we hope to further develop the theory of career construction and provide more suggestions for college consultants and students.
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Career planning and career decision are important tasks for college students. The process may be affected by career stress, career exploration, and future work self, with some students facing career indecision. Combining both construction career and proactive motivation model, this study investigated the relationships between career stress, career exploration, future work self, career planning and career indecision among 1,012 Chinese college students using the Structure equation model (SEM) to test the proposed mediation model. Results show that career stress negatively predicts career planning, while career exploration positively predicts career planning. The mediating role of future work self has on career stress and career exploration's effects on both career planning and career indecision was verified. Moreover, the study also found future work self's positive effects on both career planning and career indecision in Chinese college students. Finally, the study's theoretical and practical significance and implications are discussed.
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Job-search is considered as a developmental task for college students to move from campus to workplace. Based on the self-determination theory, 859 Chinese college students were selected as the study sample and hierarchical regression analysis was used to explore the perseverance of effort and consistency of interest on job-search intensity and clarity. The survey showed that the perseverance of effort has a significant positive effect on the job-search intensity, while it has no significant positive effect on job-search clarity. Consistency of interest has a significant negative effect on job-search intensity and a significant positive effect on job-search clarity. Theoretical and practical implications are discussed and the directions for future research are outlined in this study.
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In this work, a novel sustained released system (VCSB-Zn(II)) for zinc supplements was built by vanillin-chitosan Schiff base (VCSB) chelated with Zn2+ to improve the zinc trace element utilization ratio. Samples were characterized by FT-IR, 1H NMR, XRD, SEM, and TGA. The results showed that VCSB exhibited a more excellent chelation capacity of Zn2+ than chitosan. The chelation capacity of VCSB was about 1.7 times more than that of chitosan, corresponding to 50.96 mg/g and 29.91 mg/g, respectively. Furthermore, VCSB-Zn(II) showed excellent sustained released performance at simulated gastric fluid because of the acid slow-dissolving ability. And the higher the CN content of VCSB, the higher the cumulative release rate (Ri) of Zn2+, the highest Ri reached 77.81%. The sustained released curves were described by the first-order and Korsmeyer-Peppas equation, which described the Zn2+ sustained released performance caused by the dissolution of VCSB-Zn(II) and Fick diffusion. This Zn2+ sustained released system shows great potential in the application in the field of trace elements supplements for animals.
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Benzaldeídos/química , Quitosana/química , Zinco/química , Liberação Controlada de Fármacos , Bases de Schiff/químicaRESUMO
The employee organizational citizenship behavior for the environment (OCBE) contributes to the improvement of the organization's environment, its study is increasing in number. However, the psychological mechanism of promoting employee OCBE is still a missing link. Drawing on the theory of social information processing, this study seeks to establish the impact of green transformational leadership on employee OCBE and the mediating role of green organizational climate in this nexus. In addition, we have integrated environmental concerns to better explain the impact of this differentiation. The results show that: green transformational leadership has a significant positive impact on employee OCBE, and green organizational climate has a mediating effect on the impact of green transformational leadership on employee OCBE. Furthermore, environmental concern not only has a positive moderating effect on the influence of green transformational leadership on green organizational climate, but also positively moderates the impact of the influence of green transformational leadership on employee OCBE. This paper reveals the internal psychological mechanism of improving employee OCBE and provides ideas for promoting the sustainable development of enterprises.
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In order to deepen the understanding of the personality antecedents of students' career decidedness, this study, based on social cognitive career theory and career development theory, examined the effect of proactive personality on career decidedness as well as the mediating mechanism and moderating factors in this process. The results of the survey of 783 Chinese college students showed that proactive personality was positively related to career decidedness via career exploration, and anticipated regret moderated the relationship between proactive personality and career exploration significantly. Both theoretical and practical implications are discussed at the end of this research.
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Intelligence is innate, but grit is something everyone can develop. Grit not only enables students to stick to their goals, but also to persevere even when they fail. Career adaptability is an important concept in vocational education of college students, which is a person engaged in some work, must have a certain physical and psychological quality. Base on the self-regulation theory, this study investigated the relationship between grit and career adaptability of Chinese college student based on the self-regulatory processes. We surveyed 839 Chinese college students and tested a self-regulation model. As expected, grit was related to greater career adaptability via greater career exploration and decision self-efficacy, positive affect, and goal commitment. These findings not only broaden the theoretical framework for the effect of grit on career adaptability, but also open up a new horizon for improving college students' career adaptability in practice.
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Hepatocellular carcinoma is one of the most common malignant tumors in China and is also a major cause of cancer deaths worldwide. Recent advances in immunotherapy have identified new treatments in which immunotherapy can be combined with antiangiogenic therapy. We report a case of hepatocellular carcinoma with a tumor thrombus at the inferior vena cava-right atrium junction and multiple lung metastases after a multiple-course treatment. Treatment with sintilimab in combination with sorafenib led to a partial remission and immune-related hepatitis.
Lay abstract Hepatocellular carcinoma is often found at intermediate or advanced stages and thus often has a poor outcome. This is due to a high chance of return and spread of the cancer. Combining immunotherapy and targeted therapy can improve the anticancer effects of treatment. Here we describe a patient with hepatocellular carcinoma who developed widespread cancer after multiple-course treatment. Sintilimab combined with sorafenib shrunk the tumor. This shows this regimen as a promising treatment strategy for hepatocellular carcinoma.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Síndrome de Budd-Chiari/tratamento farmacológico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Síndrome de Budd-Chiari/patologia , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Sorafenibe/administração & dosagem , Sorafenibe/efeitos adversosRESUMO
PURPOSE: The purpose of the present study was to evaluate the feasibility of using 4-dimensional computed tomography (4DCT)-ventilation-weighted dose analysis to predict radiation-induced pneumonia probability (RIPP). METHODS AND MATERIALS: The study population for this retrospective analysis included 16 patients with stage III lung cancer. Each patient's 4DCT images, including end-inhale and end-exhale sequences, were used for the deformable image registration, and the Hounsfield units (HU) density-change was used to calculate the ventilation. A previously established equation was used to convert the original dose (OD) D 0, i in the lungs in the original plan (OP) to the weighted-dose (WD) D w, i in the weighted plan (WP). The patients were divided into 2 groups, one with radiation-induced pneumonia (RIP), and one without. The Spearman correlation analysis was used to analyze the correlation of RIP with ΔV20 (ΔV x = V w, x in the WP - V 0, x in the OP), ΔMLD (ΔMLD = mean lung dose (MLD) in the WP - MLD in the OP), and ΔV5. RESULTS: The results showed that 5 of the 16 patients were suffering from acute RIP, 4 of which had higher ΔV20 and ΔMLD values than the rest of the patients. The results of the Spearman correlation analysis for those 4 patients were as follows: RIP vs. ΔV20, r = 0.5123; RIP vs. ΔMLD, r = 0.5119; RIP vs. ΔV5, r = 0.1904. CONCLUSIONS: The 4DCT-ventilation-based weighted-dose analysis showed some correlation between RIPP and both ΔV20 and ΔMLD, when comparing the weighted-dose and the conventional dose-volume histogram (DVH) analyses.
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In recent years, there have been advancements in traditional patterns of tumor therapy with the adoption of immunotherapy. Its application with or without other combined regimens has attracted attention from clinicians. Sintilimab (Tyvyt®), a highly selective fully human IgG4 monoclonal antibody, blocks the binding site of programmed cell death protein 1 (PD-1), thereby, inhibiting the interaction between PD-1 and its ligands (PD-L1/2) to restore the endogenous anti-tumor T cell responses. Sintilimab has been proven to be clinically beneficial in multiple solid tumor therapies. Combination therapy and monotherapy have shown potential and encouraging anti-tumor efficacy with controllable and acceptable toxicities. The combination therapy is more likely to be a novel and promising therapeutic option. This study provides an overview of the status of sintilimab-based clinical trials in various solid tumors.
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Following the publication of the above article, the authors have realized that certain intended corrections were not carried over to the published version of the article. First, the description of the results of Figs. 5 and 6 did not match the figures; Edu and Transwell invasion assays were intended to have been excluded from the manuscript during the proofreading stage, although these data were presented in the description of the results for Figs. 5 and 6. Consequently, the text for the "circRNA_001275 promotes cell proliferation" subsection of the Results section towards the end of p. 153 should have read as follows: "MTT assay was used to detect the effects of circRNA_001275 on cell proliferation. The results showed that cell viability was significantly increased in the circRNA_001275 OE group, and significantly decreased in the si circRNA_001275 group (both P<0.05, Fig. 5A and B), compared with the corresponding control groups." Furthermore, the text in the subsequent subsection ("circRNA_001275 inhibits cell apoptosis") should have read as follows: "Hoechst 33258 staining was used to detect the effects of circRNA_001275 on apoptosis. The apoptosis rate was significantly decreased in the circRNA_001275 OE group, and significantly increased in the si circRNA_001275 group (both P<0.05; Fig. 6), compared with the corresponding control group. Secondly, Fig. 5B was omitted from Fig. 5 in the published article; and thirdly, a higherresolution version of Fig. 6 was submitted during the revision stages, although the version of this figure that was deemed to have been too low in quality was the one that appeared in the final proofs. The corrected / updated versions of Figs. 5 and 6 are shown opposite. The Editor of International Journal of Oncology regrets that certain of these errors were introduced into the article during the production stages, and apologizes both to the authors and to the readership. [the original article was published in International Journal of Oncology 57: 151160, 2020; DOI: 10.3892/ijo.2020.5050].
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OBJECTIVES: To test the effectiveness of quantitative linear-quadratic-based (qLQB) model on evaluating irradiation-induced liver injury (ILI) and establish the relation between the damaged ratio/percent (DRP) in qLQB model and normal tissue complication probility (NTCP). MATERIALS AND METHODS: We established the qLQB model to calculate the ratio/percent (RP) between damaged cell/functional subunit (FSU) and entire cell/FSU of liver for radiation dose response, tested the qLQB against the Lyman-Kutcher-Burman (LKB) model, and established relation between the RP and NTCP through analyzing the dose of 32 patients with cancer of abdominal cavity who were treated with radiation therapy at our department. Based on varied α/ß and varied parameters for NTCP, we put the calculated results into varied arrays for the next analysis. We named the 2 groups of RPs: RP1 (α/ß = 3.0, α = 0.03) and RP2 (α/ß = 8.0, α = 0.26), and named the 2 groups of NTCPs: NTCP1 (n = 0.32, m = 0.15, TD50(1) = 4000 cGy) and NTCP2 (n = 1.10, m = 0.28, TD50(1) = 4050 cGy). RESULTS: Spearman correlation analysis was used to analyze the correlations among the groups, the results were as follows: RP1 vs NTCP1, rs = 0.83827, p < 0.0001; RP1 vs NTCP2, rs = 0.83827, p < 0.0001; RP2 vs NTCP2, rs = 0.79289, p < 0.0001; and RP2 vs NTCP1, rs = 0.79289, p < 0.0001. CONCLUSIONS: There is a significant correlation between RP value and NTCP for evaluating ILI, and there is no difference between qLQB model and LKB model on evaluating ILI.
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E2F transcription factors (E2Fs) were found to be related with cell activities and disease progression among a variety of different tumors, including regulating cell division and cell proliferation. In the analysis, it aimed to focus on transcriptional and survival information of E2Fs in gastric cancer (GC) from Gene Expression Profiling Interactive Analysis (GEPIA), Kaplan-Meier plotter, cBioPortal, Database for Annotation, Visualization and Integrated Discovery (DAVID), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and Oncomine databases. It was found that the expression of E2F1/2/3/5/7/8 in GC tissues was obviously higher than the normal. Of interest, none of the E2Fs was related with pathological stages. Nevertheless, high expression of E2F2/3/5/7/8 was related with better survival data, except E2F6 regarding shorter first-progression (FP) survival. High expression levels of E2F2/5/7/8 have significant correlations with overall survival (OS) in patients with intestinal and diffuse GC, and this prognostic value is not affected by gender. Oppositely, the lower level of E2F1/4 illustrated superior survival data. Moreover, increased expression of E2F1 in GC tissues might play an important role in the development of GC. Collectively, E2F1 could be a potential therapeutic target for patients with GC. E2F1/2/3/5/7/8 might be original prognostic predictors of GC.
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Evidence suggests that built environment characteristics affect older adults' travel activity behaviors, e.g., walking and cycling, which have well-established health benefits. However, the relationship between urban greenery and walking behaviors remains unclear, partly due to methodological limitation. Previous studies often measured urban greenery from a bird's eye perspective, which may mismatch with the pedestrian's perception from the street. In this study, we measured greenery view index from eye-level streetscape photos retrieved from Baidu Street View, an online mapping service provider. Walking behaviors of 180 older adults in six neighborhoods were collected from questionnaires. We also measured land use diversity, pedestrian-oriented design (street connectivity), and population density-the three Ds of the built environment. Results show that street greenery view index contributes to walking time of older adults, suggesting street greenery should be taken into design consideration to promote walking behaviors of older adults.
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Planejamento Ambiental , Pedestres , Caminhada , Idoso , Idoso de 80 Anos ou mais , Olho , Feminino , Humanos , Masculino , Características de ResidênciaRESUMO
OBJECTIVE: To explore the efficacy and sensitivity of 3D gamma analysis and bio-mathematical model for cervical cancer in detecting dose changes caused by dose-calculation-grid-size (DCGS). METHODS: 17 patients' plans for cervical cancer were enrolled (Pinnacle TPS, VMAT), and the DCGS was changed from 2.0 mm to 5.0 mm to calculate the planned dose respectively. The dose distribution calculated by DCGS = 2.0 mm as the "reference" data set (RDS), the dose distribution calculated by the rest DCGS as the"measurement"data set (MDS), the 3D gamma passing rates and the (N) TCPs of the all structures under different DCGS were obtained, and then analyze the ability of 3D gamma analysis and (N) TCP model in detecting dose changes and what factors affect this ability. RESULTS: The effect of DCGS on planned dose was obvious. When the gamma standard was 1.0 mm, 1.0 and 10.0%, the difference of the results of the DCGS on dose-effect could be detected by 3D gamma analysis (all p value < 0.05). With the decline of the standard, 3D gamma analysis' ability to detect this difference shows weaker. When the standard was 1.0 mm, 3.0 and 10.0%, the p value of > 0.05 accounted for the majority. With DCGS = 2.0 mm being RDS, ∆gamma-passing-rate presented the same trend with ∆(N) TCPs of all structures except for the femurs only when the 1.0 mm, 1.0 and 10.0% standards were adopted for the 3D gamma analysis. CONCLUSIONS: The 3D gamma analysis and bio-mathematical model can be used to analyze the effect of DCGS on the planned dose. For comparison, the former's detection ability has a lot to do with the designed standard, and the latter's capability is related to the parameters and calculated accuracy instrinsically.
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Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias do Colo do Útero/radioterapia , Feminino , Raios gama , Humanos , Modelos Teóricos , Dosagem Radioterapêutica , Estudos RetrospectivosRESUMO
Circular RNAs (circRNAs) are aberrantly expressed in various tumors and are associated with tumorigenesis. The present study aimed to determine the role of circRNA_001275 in cisplatinresistant esophageal cancer. Three pairs of cisplatinresistant tissues and corresponding adjacent tissues were collected and subjected to circRNA chip analysis. Additionally, the effect of circRNA_001275 on cisplatinresistant cells was investigated. The relationship between circRNA_001275, microRNAs (miRs) and target genes were analyzed using luciferase assays, and validated via reverse transcriptionquantitative PCR (RTqPCR) and western blotting. The results showed that circRNA_001275 was significantly upregulated in cisplatinresistant esophageal cancer tissues and cells (P<0.05). Overexpression of circRNA_001275 promoted the proliferation and invasion, and decreased the apoptosis of cisplatinresistant cells. On the other hand, circRNA_001275 silencing inhibited cell proliferation and invasion, and promoted cell apoptosis (P<0.05). Dualluciferase reporter assays revealed that circRNA_001275 directly binds to miR3703p, and that Wnt family member 7A (Wnt7a) is targeted by miR3703p. RTqPCR and western blotting further demonstrated that circRNA_001275 serves as an miR3703p sponge to upregulate Wnt7a expression. In conclusion, the present study revealed that circRNA_001275 was upregulated in cisplatinresistant esophageal cancer and promoted cisplatin resistance by sponging miR3703p to upregulate Wnt7a expression. Therefore, circRNA_001275 may serve as a potential diagnostic biomarker and therapeutic target for patients with cisplatinresistant esophageal cancer.
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Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Esofágicas/tratamento farmacológico , MicroRNAs/metabolismo , RNA Circular/metabolismo , Proteínas Wnt/genética , Idoso , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Cisplatino/uso terapêutico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Regulação para CimaRESUMO
Applying categorization rules narrows attention toward the relevant features of a target and helps participants to ignore the irrelevant features of the target. This is called the shielding function of categorization rules. Here we explored the limitation of the shielding function in two task-switching experiments. In Experiment 1, we assigned each target a single digital numeral as an additional feature in addition to conventional bivalent features as in the previous task-switching experiments with bivalent tasks. In the first two stages of Experiment 1, half of the participants learned the numeral-response associations and the other half used an alternative numeral-categorization rule to infer the response. Without participants applying conventional task-switching rules, the switching costs disappeared. Moreover, when participants performed tasks by numeral-response associations the bivalent features interfered with response retrieval and caused response-congruency effects, whereas when participants applied the numeral-categorization rule, the bivalent features were shielded away and thereby the response-congruency effects disappeared. In the third stage, in which all participants applied task-switching rules by discriminating between bivalent features (i.e., filling and orientations), we found task-switching costs and response-congruency effects. In Experiment 2, new bivalent features produced stronger interference compared to Experiment 1. As a consequence, participants in both the association group and the numeral-categorization rule group showed significant response-congruency effects in the first two stages, where task-switching rules were not introduced. It follows that the shielding function of categorization rules has limits-strong interference from bivalent features can break down the shielding function. In addition, participants in the association group showed task-switching costs without being informed about the task-switching rules. We propose that strong proactive interference can produce task-switching costs even without the use of task-switching rules.
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In experiments with univalent target stimuli, task-switching costs can be eliminated if participants are unaware of the task rules and apply cue-target-response associations. However, in experiments with bivalent target stimuli, participants show task-switching costs. Participants may exhibit switch costs even when no task rules are provided in the instructions because they can infer the task rules. We tested this prediction by controlling the meaningfulness of cues and targets and therefore the ability to apply the task rules in 2 groups of participants. We compared the performance of Chinese and non-Chinese participants, who responded to Chinese numerals in an odd/even and high/low number task. In Experiment 1, Chinese participants, who knew Chinese characters and understood the task rules, showed task-switching costs. Non-Chinese participants on the other hand, who did not know Chinese characters, exhibited no switch costs. They applied a "target-first" strategy which means that they processed the target stimulus before the cue. In Experiment 2, we confirmed the absence of task-switching costs in Chinese participants using traditional Chinese numerals as target stimuli. Further, to determine how the target-first strategy affects switch costs, we manipulated the sequence of cue and target presentations. We conclude that task-switching costs can be eliminated more easily than previously thought, even for bivalent stimuli. The occurrence of task-switching costs depends on the approach used by participants and this may answer the puzzling question why humans typically do show task-switching costs whereas pigeons and monkeys do not. (PsycINFO Database Record (c) 2019 APA, all rights reserved).