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OBJECTIVES: Generalization (or near-transfer) effects of an intervention to tasks not explicitly trained are the most desirable intervention outcomes. However, they are rarely reported and even more rarely explained. One hypothesis for generalization effects is that the tasks improved share the same brain function/computation with the intervention task. We tested this hypothesis in this study of transcranial direct current stimulation (tDCS) over the left inferior frontal gyrus (IFG) that is claimed to be involved in selective semantic retrieval of information from the temporal lobes. MATERIALS AND METHODS: In this study, we examined whether tDCS over the left IFG in a group of patients with primary progressive aphasia (PPA), paired with a lexical/semantic retrieval intervention (oral and written naming), may specifically improve semantic fluency, a nontrained near-transfer task that relies on selective semantic retrieval, in patients with PPA. RESULTS: Semantic fluency improved significantly more in the active tDCS than in the sham tDCS condition immediately after and two weeks after treatment. This improvement was marginally significant two months after treatment. We also found that the active tDCS effect was specific to tasks that require this IFG computation (selective semantic retrieval) but not to other tasks that may require different computations of the frontal lobes. CONCLUSIONS: We provided interventional evidence that the left IFG is critical for selective semantic retrieval, and tDCS over the left IFG may have a near-transfer effect on tasks that depend on the same computation, even if they are not specifically trained. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT02606422.

This study aimed to examine the chain mediating role of moral identity and self-control between social class and Internet altruistic behavior (IAB) in a sample of Chinese undergraduates. A total of 388 participants (M.sub.age = 19.45, SD = 1.44, 43.81% males) completed the MacArthur Subjective Social Class Ladder, the Moral Identity Scale, the Brief Self-Control Scale and the IAB Scale. The results confirmed that social class could not only directly affect IAB, but also affect individuals' IAB through three paths: The mediating role of moral identity, the mediating role of self-control, and the chain mediating role of moral identity and self-control after controlling for gender, age and weekly online time. These findings contribute to a deeper understanding of how social class affects IAB and provide important practical guidance for enhancing IAB., Author(s): Xianliang Zheng [sup.1] , Huiping Chen [sup.1] , Zeyi Wang [sup.1] , Fangwei Xie [sup.1] , Zhenzhou Bao [sup.1] Author Affiliations: (1) grid.464274.7, 0000 0001 2162 0717, School of [...]

Replicability, the ability to replicate scientific findings, is a prerequisite for scientific discovery and clinical utility. Troublingly, we are in the midst of a replicability crisis. A key to replicability is that multiple measurements of the same item (e.g., experimental sample or clinical participant) under fixed experimental constraints are relatively similar to one another. Thus, statistics that quantify the relative contributions of accidental deviations-such as measurement error-as compared to systematic deviations-such as individual differences-are critical. We demonstrate that existing replicability statistics, such as intra-class correlation coefficient and fingerprinting, fail to adequately differentiate between accidental and systematic deviations in very simple settings. We therefore propose a novel statistic, discriminability, which quantifies the degree to which an individual's samples are relatively similar to one another, without restricting the data to be univariate, Gaussian, or even Euclidean. Using this statistic, we introduce the possibility of optimizing experimental design via increasing discriminability and prove that optimizing discriminability improves performance bounds in subsequent inference tasks. In extensive simulated and real datasets (focusing on brain imaging and demonstrating on genomics), only optimizing data discriminability improves performance on all subsequent inference tasks for each dataset. We therefore suggest that designing experiments and analyses to optimize discriminability may be a crucial step in solving the replicability crisis, and more generally, mitigating accidental measurement error.

【Objective】 Sunflower is a cash crop grown in arid northwestern China. Improving its water use efficiency plays an important role in developing water-saving agriculture in that region. The aim of this paper is to find an optimal regulated and mulched deficit drip irrigation scheduling for it. 【Method】 The experiment was conducted in 2019—2020 in a sunflower field at Hexi Oasis. Water deficit was imposed at seedling and maturity stages, with soil water in other growing stages kept sufficient for roots to extract. Overall, there were six treatments, with the water deficit induced by keeping the soil water content at 75%~65% (mild), 65%~55% (moderate) and 55%~45% (severe) of the field capacity, respectively. The control was sufficient irrigation with the soil water content kept at 75%~85% of the field capacity. Each treatment had three replicas, which were designed using the completely random block experiment arrangement. The experimental results were analyzed using an improved fuzzy matter-element model coupled with the weighted game theory to quantify the effect of different water deficits on yield and quality, as well as water productivity of the crop. 【Result】 The effect of water deficit on the crop traits varied. A multi-level evaluation system revealed that in 2019, crop height had the highest weight (0.141) and the crude protein content had the least (0.083), while in 2020, crude fat content had the highest weight (0.162) and water use efficiency had the least (0.065). Comprehensive evaluation of the fuzzy matter-element model showed that the Euclidean degree was the best for a combination of mild or moderate water deficit at seedling stage and mild water deficit at maturity stage. 【Conclusion】 When water is sufficient, a mild regulated deficit irrigation (RDI) at the seedling stage coupled with a mild RDI at the maturity stage produces the highest seed yield, while when water is insufficient, a moderate RDI at the seedling stage combined with a mild RDI at the maturity stage works the best. The proposed model for optimizing regulated deficit irrigation is applicable not only for sunflower watered by mulched drip irrigation, but also for other crops irrigated by other methods.

ObjectiveTranscranial direct current stimulation (tDCS) has shown promising results when used as an adjunct to behavioral training in neurodegenerative diseases. However, the underlying neural mechanisms are not understood and neuroimaging evidence from pre/post treatment has been sparse. In this study, we examined tDCS-induced neural changes in a language intervention study for primary progressive aphasia (PPA), a neurodegenerative syndrome with language impairment as the primary clinical presentation. Anodal tDCS was applied to the left inferior frontal gyrus (LIFG). To evaluate the hypothesis that tDCS promotes system segregation, analysis focused on understanding tDCS-induced changes in the brain-wide functional network connectivity of the targeted LIFG.MethodsResting-state fMRI data were obtained from 32 participants with PPA before and after receiving a written naming therapy, accompanied either by tDCS or sham stimulation. We focused on evaluating changes in the global connectivity of the stimulated LIFG-triangularis (LIFG-tri) region given its important role in lexical processing. Global connectivity was indexed by the graph-theoretic measure participation coefficient (PC) which quantifies a region's level of system segregation. The values before and after treatment were compared for each condition (tDCS or Sham) as well as with age-matched healthy controls (n = 19).ResultsHigher global connectivity of the LIFG-tri before treatment was associated with greater dementia severity. After treatment, the tDCS group showed a significant decrease in global connectivity whereas the Sham group's did not change, suggesting specific neural effects induced by tDCS. Further examination revealed that the decrease was driven by reduced connectivity between the LIFG-tri and regions outside the perisylvian language area, consistent with the hypothesis that tDCS enhances the segregation of the language system and improves processing efficiency. Additionally, we found that these effects were specific to the LIFG-tri and not observed in other control regions.ConclusionTDCS-augmented language therapy in PPA increased the functional segregation of the language system, a normalization of the hyper-connectivity observed before treatment. These findings add to our understanding of the nature of tDCS-induced neural changes in disease treatment and have applications for validating treatment efficacy and designing future tDCS and other non-invasive brain stimulation (NIBS) treatments.

The current study aims to determine the brain areas critical for response to anodal transcranial direct current stimulation (tDCS) in PPA. Anodal tDCS and sham were administered over the left inferior frontal gyrus (IFG), combined with written naming/spelling therapy. Thirty people with PPA were included in this study, and assessed immediately, 2 weeks, and 2 months post-therapy. We identified anatomical areas whose volumes significantly predicted the additional tDCS effects. For trained words, the volumes of the left Angular Gyrus and left Posterior Cingulate Cortex predicted the additional tDCS gain. For untrained words, the volumes of the left Middle Frontal Gyrus, left Supramarginal Gyrus, and right Posterior Cingulate Cortex predicted the additional tDCS gain. These findings show that areas involved in language, attention and working memory contribute to the maintenance and generalization of stimulation effects. The findings highlight that tDCS possibly affects areas anatomically or functionally connected to stimulation targets.