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Studies have found that flipped classroom teaching (FT) improves learning compared to lecture-based teaching (LT). However, whether the structured teacher–student interaction—the key feature of FT—plays an essential role in enhancing learning remains unclear, as do its neural underpinnings. Here, we compared three teaching conditions: FT with a video lecture and structured interaction, LT with a face-to-face lecture and spontaneous interaction, and control teaching (CT) with a video lecture and spontaneous interaction. The fNIRS-based hyperscanning technique was used to assess the interbrain synchrony (IBS) from teacher-student dyads. Results showed that the learning was significantly improved in FT than in LT and CT, and FT significantly increased teacher–student IBS in left DLPFC. Moreover, the IBS and learning improvements were positively correlated. Therefore, these findings indicate that the structured teacher–student interaction is crucial for enhancing learning in FT, and IBS serves as its neural foundation. [ABSTRACT FROM AUTHOR]

The objective of this study is to explore the correlation of metal levels with assisted reproductive technology (ART) outcomes in polycystic ovary syndrome (PCOS) patients. The individuals were recruited who met the research criteria, only tubal factor or male infertility served as the control group (n = 40) and patient group was PCOS patients (n = 35). Individuals (n = 75) were divided into PCOS group (n = 35) and control group (n = 40). The normal body mass index (BMI) group (control) includes women with BMI < 25 kg/m2 in PCOS group (n = 24) and control group (n = 33), and BMI ≥ 25 kg/m2 in PCOS group (n = 11) and control group (n = 7). We performed an analysis of insulin resistance (IR) (n = 15) group and without insulin resistance (NIR) group (n = 20) in PCOS patient and control patients. Comparing difference demographic data, ART outcomes and the metal levels in every group respectively, the correlation of metal levels and ART outcomes in control participants and PCOS patients were analyzed by the Spearman correlation analysis, and multiple linear regression model was used to examine the association between the concentration of 19 metals and ART outcomes in PCOS group and control group. Plasma manganese (Mn), titanium (Ti), sodium (Na), magnesium (Mg), copper (Cu), calcium (Ca)/Mg ratio, and Cu/zinc (Zn) ratio levels in PCOS patients were higher than that in control, while Zn and Ca levels were lower in PCOS patients than that in control. The Mg levels had a positive connection with the number of eggs recovered, and the iron (Fe) levels were positively associated with the number of transplanted embryos in PCOS-IR. In PCOS-NIR, Mn levels positively correlated with the number of follicles and the number of good embryos. Silver (Ag) levels were negatively correlated with the number of follicles, and aluminum (Al) levels were negatively related with the normal fertilization and the number of good embryos. The Spearman analysis in PCOS-BMI ≥ 25 group exhibited that nickel (Ni) levels were negatively associated with the number of follicles. The plasma metal levels seem to affect the clinical manifestations and in vitro fertilization outcomes in assisted reproduction. [ABSTRACT FROM AUTHOR]

DNA methylation plays a significant role in regulating transcription and exhibits a systematic change with age. These changes can be used to predict an individual's age. First, to identify methylation sites associated with biological age; second, to construct a biological age prediction model and preliminarily explore the biological significance of methylation-associated genes using machine learning. A biological age prediction model was constructed using human methylation data through data preprocessing, feature selection procedures, statistical analysis, and machine learning techniques. Subsequently, 15 methylation data sets were subjected to in-depth analysis using SHAP, GO enrichment, and KEGG analysis. XGBoost, LightGBM, and CatBoost identified 15 groups of methylation sites associated with biological age. The cg23995914 locus was identified as the most significant contributor to predicting biological age by calculating SHAP values. Furthermore, GO enrichment and KEGG analyses were employed to initially explore the methylated loci's biological significance. [ABSTRACT FROM AUTHOR]

During infection viruses hijack host cell metabolism to promote their replication. Here, analysis of metabolite alterations in macrophages exposed to poly I:C recognises that the antiviral effector Protein Kinase RNA-activated (PKR) suppresses glucose breakdown within the pentose phosphate pathway (PPP). This pathway runs parallel to central glycolysis and is critical to producing NADPH and pentose precursors for nucleotides. Changes in metabolite levels between wild-type and PKR-ablated macrophages show that PKR controls the generation of ribose 5-phosphate, in a manner distinct from its established function in gene expression but dependent on its kinase activity. PKR phosphorylates and inhibits the Ribose 5-Phosphate Isomerase A (RPIA), thereby preventing interconversion of ribulose- to ribose 5-phosphate. This activity preserves redox control but decreases production of ribose 5-phosphate for nucleotide biosynthesis. Accordingly, the PKR-mediated immune response to RNA suppresses nucleic acid production. In line, pharmacological targeting of the PPP during infection decreases the replication of the Herpes simplex virus. These results identify an immune response-mediated control of host cell metabolism and suggest targeting the RPIA as a potential innovative antiviral treatment. Synopsis: Although the cellular immune response controls metabolism to try to limit viral infection, the mechanisms involved remain poorly understood. This study identifies the antiviral effector RNA-activated protein kinase PKR as a control factor for glucose breakdown in the pentose phosphate pathway (PPP), limiting pentose precursor generation, nucleic acid synthesis and viral proliferation. Antiviral response by PKR alters cellular glucose metabolism, limiting ribose 5-phosphate production in the non-oxidative PPP. PKR-mediated control of the PPP is kinase function-dependent but distinct from its role in gene expression. PKR phosphorylates Ribose 5-Phosphate Isomerase A (RPIA), suppressing ribose 5-phosphate production. Pharmaceutical targeting of the PPP limits Herpes simplex virus replication. RNA-activated protein kinase counters viral infection by suppressing a pentose phosphate pathway precursor required for virus genome replication. [ABSTRACT FROM AUTHOR]

Hematopoietic progenitor kinase 1 (HPK1) is a negative regulator of T-cell receptor signaling and as such is an attractive target for cancer immunotherapy. Although the role of the HPK1 kinase domain (KD) has been extensively characterized, the function of its citron homology domain (CHD) remains elusive. Through a combination of structural, biochemical, and mechanistic studies, we characterize the structure-function of CHD in relationship to KD. Crystallography and hydrogen-deuterium exchange mass spectrometry reveal that CHD adopts a seven-bladed β-propellor fold that binds to KD. Mutagenesis associated with binding and functional studies show a direct correlation between domain-domain interaction and negative regulation of kinase activity. We further demonstrate that the CHD provides stability to HPK1 protein in cells as well as contributes to the docking of its substrate SLP76. Altogether, this study highlights the importance of the CHD in the direct and indirect regulation of HPK1 function. In this work, the authors unveil a mechanism where the Citron homology domain regulates HPK1's kinase domain, shedding light on the relationship between HPK1's structure and function. This enhances our understanding of HPK1, an intracellular target for cancer immunotherapy and provides a direction for immuno-oncology drug discovery. [ABSTRACT FROM AUTHOR]

School adjustment of left-behind children (LBC) is a significant public health issue that may affect their well-being and mental health. In China, most left-behind children have a family structure in which the father goes out to work and the mother stays at home to take care of the children. As the sole caregiver in the family, a mother who shows support or destruction to the father's parenting goals or behaviors in the process of raising children may affect the LBC's school adjustment. However, the relationship between mothers' co-parenting and LBC's school adjustment and its mechanisms are unclear. This study aimed to explore the longitudinal influence of mothers' co-parenting on school adjustment of father-absent LBC, and the mediating roles of paternal and maternal attachment. 284 father-absent LBC (177 boys and 107 girls) aged 8–11 (Mage = 8.43, SDage = 0.73) from Anhui Province completed questionnaires about mothers' co-parenting, paternal and maternal attachment, and children's school adjustment at two time. The results showed that (1) mothers' positive co-parenting positively predicted LBC's social competence, and mothers' negative co-parenting positively predicted LBC's antisocial behaviors; (2) Maternal attachment mediated the relationship between mothers' co-parenting and LBC's social competence, while paternal attachment mediated the association between mothers' positive co-parenting and LBC's antisocial behaviors. This study reveals the effect of mothers' co-parenting on the school adjustment of father-absent LBC, and the unique mediating role of paternal and maternal attachment. Moreover, this research suggested that encouraging mothers to exhibit more positive co-parenting behaviors, reducing conflict and disparaging fathers, may be an effective way to promote LBC's school adjustment. Highlights: Mothers' positive co-parenting promotes the development of father-absent LBC's social competence, while mothers' negative co-parenting promotes the occurrence of father-absent LBC's antisocial behaviors. Maternal attachment mediated the relationship between mothers' co-parenting and LBC's social competence, while paternal attachment mediated the association between mothers' positive co-parenting and LBC's antisocial behaviors. This research suggested that encouraging mothers to show more positive co-parenting behaviors, reducing conflict and disparaging fathers, is beneficial to the development of maternal and paternal attachment, and further promotes father-absent LBC's school adjustment. [ABSTRACT FROM AUTHOR]

Left-behind children's internalizing and externalizing problem behaviors have become an important public health issue that may affect their well-being and mental health. Interparental conflict, a stronger and cannot be hidden family risk factor, is easily perceived by LBC and further affects LBC's internalizing and externalizing problem behaviors. Moreover, in LBC's families, interparental conflict are more likely to occur due to the poor economic status and the low quality of communication and interaction between parents. However, no research has examined the relationship between perceived interparental conflict and LBC's internalizing and externalizing problem behaviors. Besides, previous research of the association between parents and children's problem behaviors have been largely restricted to the unidirectional effect of parental traits on children. This study aimed to examine the reciprocal relationships between perceived interparental conflict and LBC's internalizing and externalizing problem behaviors following a three-wave longitudinal design. A total of 660 LBC (442 boys and 218 girls) aged 8–11 years (Mage = 9.58, SDage = 0.67 at T1) in China completed a battery of questionnaires at three time points. The results indicated that perceived interparental conflicts positively predicted LBC's internalizing and externalizing problem behaviors. In turn, LBC's internalizing problem behaviors exacerbated the perception of interparental conflicts. Furthermore, perceived interparental conflict mediated the longitudinal relation between LBC's internalizing problem behaviors and externalizing problem behaviors. The findings provide evidence for the accumulating disadvantage for LBC that results from the mutual reinforcement of perceived interparental conflict and problem behaviors over time. [ABSTRACT FROM AUTHOR]

The success or failure of executing the watershed ecological compensation (WEC) policy is primarily contingent on incentive designs. How do different contractual designs influence the actions of micro-individuals in WEC? How may individuals be enticed to engage in WEC project? Taking the first inter-provincial WEC-Xin'an River Basin (XRB) pilot in China as a case, this study investigates the impacts of government-oriented, market-oriented, and incentive-cooperation contracts on individuals' behavior based on the framework of Stackelberg games. Subsequently, differences in efforts and profits of diverse individuals are compared and analyzed for each contract. The case-specific numerical example is then utilized to validate theoretical outcomes and to support subsequent key insights. First, the government-oriented contract exhibits effectiveness in bolstering the efforts and interests of micro-individuals, whereas it also places the government under tremendous financial strain. Second, the market-oriented contract formed by the output contribution rate assists in overcoming deficiencies of excurrent government-oriented contract. But it remains controversial if, in the absence of government inspection, investors that devote more cooperative-efforts are not rewarded with further dividends, ultimately diminishing their enthusiasm for the WEC-XRB project. Lastly, the incentive-cooperation contract reinforced by market dominance is advantageous for improving the efficacy of water resource management under the existing government-oriented policy relying on command-and-control instruments. [ABSTRACT FROM AUTHOR]

Due to the lack of parental care, the issue of left-behind children (LBC)'s mental health has been highlighted in the academic field. In LBC's families, a large proportion of fathers migrated to other cities for work. Migrated fathers' involvement also has crucial impacts on children's development, but previous studies focused less on it. Thus, using the longitudinal data of two waves, current study examined the relationship between fathers' involvement and the LBC's mental health from the perspective of the Dual-Factor Model of Mental Health and its underlying mechanism. A total of 613 LBC at primary schools in China completed questionnaires twice about fathers' involvement, paternal and maternal attachment, life satisfaction, prosocial behavior, internalizing problems, and externalizing problems. The results showed that the total effects of fathers' involvement on LBC's life satisfaction and prosocial behavior were significant, while those on problem behaviors were insignificant. Also, father-child attachment played a mediating role in the association between fathers' involvement and the positive indicators of LBC's mental health. Meanwhile, mother-child attachment mediated the relationships between fathers' involvement and LBC's problem behaviors. The study not only highlights the positive influence of fathers' involvement on LBC as well as the relations among different subsystems in the family but also implies the different effects of paternal and maternal attachment on LBC's mental health, which brings inspiration for improving the mental health of LBC in China. [ABSTRACT FROM AUTHOR]

Objectives: Abundant evidence has demonstrated that self-compassion is beneficial in alleviating psychological problems and improving mental health. However, little attention has been paid to the developmental mechanism of self-compassion in childhood. Few studies have examined the influence of paternal/maternal attachment on children's self-compassion in childhood. Moreover, it remains unclear whether children's self-compassion affects their interactions with their parents. The purpose of this study is to explore the bidirectional relationship between paternal/maternal attachment and children's self-compassion. Methods: Participants (N = 990; 64.6% male, Mage = 9.58, SDage = 0.70) were recruited from three primary schools in Anhui Province, China. Participants completed three self-report questionnaires assessing children's self-compassion, paternal attachment, and maternal attachment at two times (approximately spaced 1 year between two time points). Results: The results displayed that paternal attachment significantly only predicted boys' self-compassion. In contrast, the effects of maternal attachment on children's self-compassion appeared to be of negligible magnitude among both boys and girls. In addition, we also found that self-compassion positively predicted paternal attachment and maternal attachment among both boys and girls. Conclusions: Our findings highlight that paternal attachment promotes the development of self-compassion in Chinese children (especially boys), and that children's self-compassion promotes paternal and maternal attachment. Future interventions should focus on the important role of paternal attachment in the development of self-compassion in children (especially boys). In addition, future research could consider interventions based on children's self-compassion to improve the quality of parent–child interactions. [ABSTRACT FROM AUTHOR]

Whether financial agglomeration is conducive to improving the green efficiency of water resources is of great significance for China to realize water saving and consumption reduction, and green sustainable development. Based on the panel data of 30 provinces in China from 2006 to 2017, this paper uses the SBM model with undesirable output to measure the green efficiency of water resources in China and empirically examines the impact of financial agglomeration on the green efficiency of water resources. The results show that the green efficiency of water resources in China presents the "N" type fluctuation characteristic, and the overall trend is increasing. The mean value of green efficiency of water resources in China fluctuates around 0.6, which is at a medium level, and there is still a large room for improvement. Secondly, there are obvious spatial differences in China's green efficiency of water resources, showing a gradient of "Eastern>Central>Western." Thirdly, at the national level, financial agglomeration has a significant positive impact on the green efficiency of water resources, and there is an inverted "U"-shaped relationship between financial agglomeration and green efficiency of water resources. Fourthly, at the regional level, the impact of financial agglomeration on green efficiency of water resources has significant regional differences. Finally, based on the above conclusions, specific proposals for financial agglomeration to improve the green efficiency of water resources are put forward. [ABSTRACT FROM AUTHOR]

Synopsis: [ABSTRACT FROM AUTHOR]

The Maguan (MG) region in the southwestern part of the South China Block contains many Neogene potassic basaltic volcanic rocks along the Ailao Shan–Red River (ASRR) shear zone. These alkaline volcanic rocks contain abundant peridotite xenoliths which are mostly spinel (Spl)-facies lherzolite. We examined xenoliths in young, ~12 Ma, alkaline basalts. Most contain clinopyroxene (Cpx), >15 vol%, and minor xenoliths contain low Cpx, ~10 vol%. Olivine (Ol) shows forsterite components ranging from 88.6 to 90.1 in most lherzolite and from 90.4 to 90.8 in depleted lherzolite, Spl Cr# (=Cr/(Cr + Al)) between 0.08–0.11 for lherzolite and 0.17–0.22 for depleted lherzolite. Platinum group elements (PGE) show a near flat primitive mantle-normalized pattern; the ratios of IPGE/PPGE are 1.3–1.8 for lherzolite and 2.1 for depleted lherzolite. The xenoliths do not contain metasomatic minerals, but Cpx in depleted lherzolite samples is enriched in light rare earth elements (LREE; (La/Sm)N = 0.97–1.74). Two pyroxene geothermometry gives the temperatures ranging from 1029 °C to 1148 °C (average 1087 °C, n = 13). Spl–Ol geothermobarometry yields the oxidation state ranging from FMQ −1.5 to −0.25 with an average value of FMQ −0.59 (n = 13), which is comparable to those of abyssal peridotite and the asthenospheric mantle. The calculated temperatures and oxidation state are similar among samples independent of mineralogy and mineral chemistry, suggesting that partial melting and the cryptic metasomatism did not change the oxidation conditions. The data suggest that the subcontinental lithospheric mantle (SCLM) beneath the region formed from the asthenosphere mantle. Since the South China Block is generally underlain by Proterozoic SCLM, the data obtained this study suggest that the ancient lithosphere was replaced by the asthenospheric mantle in the local extension along the ASRR shear zone. [ABSTRACT FROM AUTHOR]

Tobacco vein banding mosaic virus (TVBMV) is of increasing importance in tobacco production. Knowledge of the genetic structure and variability of the virus population is vital for developing sustainable management. In this study, 24 new TVBMV isolates from Sichuan Province together with 46 previous isolates were studied based on their coat protein sequences. Two distinguishable clades were supported by phylogenetic analysis. The summary statistics PS, AI and MC showed a strong TVBMV-geography association between the isolates from Southwest China (SW) and Mainland China (MC). Further analysis indicated that the spatial genetic structure of TVBMV populations is likely to have been caused by natural selection. Phylogeographic analysis provided strong support for spatial diffusion pathways between the Southwest and Northwest tobacco-producing regions. The TVBMV CP gene was found to be under negative selection, and no significant positive selection of amino acids was detected in the SW group; however, the isolates of the MC group experienced significant positive selection pressure at the first and third amino acid sites of CP. This study suggests that natural selection and habitat heterogeneity are important evolutionary mechanisms affecting the genetic structure of the TVBMV population. [ABSTRACT FROM AUTHOR]

The Yao'an Pb-Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang-Ailaoshan alkaline porphyry-related polymetallic intrusive belt. This complex suite of rock bodies includes a vein of pseudoleucite porphyry within deposits of syenite porphyry and trachyte. The pseudoleucite is characterized by a variable greyish, greyish-white, and greyish-green porphyritic texture. Phenocrysts are mainly pseudoleucite with small amounts of alkali feldspar and biotite. In an intense event, leucite phenocrysts altered to orthoclase, kaolinite, and quartz. Both the pseudoleucite porphyry and the syenite porphyry samples were typical alkali-rich, K-rich, al-rich rocks with high La/Yb ratios; enriched in light rare earth elements and large-ion lithophile elements, and depleted in high field strength elements; and with strongly negative Ta, Nb, and Ti (TNT) anomalies and slightly negative Eu anomalies-all characteristics of subduction-zone mantle-derived rock. We obtained a LA-ICP-MS zircon U-Pb age of 34.1 ± 0.3 Ma (MSWD = 2.4), which is younger than the established age of the Indian and Eurasian Plate collision. The magma derived from a Type-II enriched mantle formed in a post-collisional plate tectonic setting. The geochemical characteristics of the Yao'an pseudoleucite porphyry are powerful evidence that the porphyry's development was closely linked to the Jinshajiang-Ailaoshan fault and to the Indian-Eurasian collision. [ABSTRACT FROM AUTHOR]

Enhancer of zeste 2 (Ezh2) mainly methylates lysine 27 of histone-H3 (H3K27me3) as part of the polycomb repressive complex 2 ( PRC2) together with Suz12 and Eed. However, Ezh2 can also modify non-histone substrates, although it is unclear whether this mechanism has a role during development. Here, we present evidence for a chromatin-independent role of Ezh2 during T-cell development and immune homeostasis. T-cell-specific depletion of Ezh2 induces a pronounced expansion of natural killer T ( NKT) cells, although Ezh2-deficient T cells maintain normal levels of H3K27me3. In contrast, removal of Suz12 or Eed destabilizes canonical PRC2 function and ablates NKT cell development completely. We further show that Ezh2 directly methylates the NKT cell lineage defining transcription factor PLZF, leading to its ubiquitination and subsequent degradation. Sustained PLZF expression in Ezh2-deficient mice is associated with the expansion of a subset of NKT cells that cause immune perturbation. Taken together, we have identified a chromatin-independent function of Ezh2 that impacts on the development of the immune system. [ABSTRACT FROM AUTHOR]

In this study, local circulations and their responses to land use and land cover (LULC) changes over the Yellow Mountains of China are examined by using Weather Research and Forecast (WRF) model simulations of a selected case under weak-gradient synoptic conditions. The results show that mountain-valley breezes over the region are characterized by an intense upslope flow lasting for about 11 h (0600-1700 LST) along the northern slope during daytime. A convergence zone occurs at the mountain ridge and moves northwest-ward with time. During nighttime, wind directions are reversed, starting first at higher elevations. Three sensitivity experiments are conducted, in which the current land covers are replaced by grassland, mixed forest, and bare soil, respectively, while keeping the other model conditions identical to a control run. These sensitivity simulations are designed to represent the changes of LULC over the Yellow Mountains area during the past decades. The results show that changes in land cover could affect substantially land-surface and atmosphere interactions, the evolution of local circulations, and characteristics of the planetary boundary layer (PBL). Significant differences are noted in horizontal winds, and sensible and latent heat fluxes. On the other hand, when the surface is covered by mixed forest, slight variations in local winds and surface variables are identified. The results appear to have important implications to urban planning and constructions as well as the transport of air pollutants over mountainous regions. [ABSTRACT FROM AUTHOR]

Here we report that ILK localizes in the mouse primary cilium, a sensory organelle required for signalling by the Hedgehog (Hh) pathway. Genetic or pharmacological inhibition of ILK blocks ciliary accumulation of the Hh pathway effector smoothened (Smo) and suppresses the induction of Gli transcription factor mRNAs by SHh. Conditional deletion of ILK or Smo also inhibits SHh-driven activation of Gli2 in the embryonic mouse cerebellum. ILK regulation of Hh signalling probably requires the physical interaction of ILK and Smo in the cilium, and we also show selective cilia-associated interaction of ILK with β-arrestin, a known mediator of Smo-dependent signalling. [ABSTRACT FROM AUTHOR]

In this study, the Weather Research and Forecasting (WRF) model (version 3.1.1) was used to simulate a thunderstorm event which occurred on August 18, 2010, over the Yellow Mountain area of China. This event was a typical thunderstorm embedded in high-pressure systems. First, the development processes of mountain-valley breeze and convective cells were studied; second, this study focused on revealing the influencing mechanism of complex topography and heterogeneous land cover on thunderstorm by removing the Yellow Mountain and changing the land use categories. On flat terrain, the simulated results displayed that the convection weakened persistently, cloud top decreased sharply, and intensity of precipitation reduced. Moreover, there was no up-slope valley breeze, convergence, and lifting of water vapor could be found on the mountaintop. Then, the role of land use was revealed by changing original land cover into grassland, mixed forests, and bare soil in the innermost area, respectively. When covered by grassland, there were less sensible heating and lower moisture, leading to the planet boundary layer height decreasing and vertical lifting weakening, which tended to cause more stable atmosphere and less rainfall on the mountaintop; when covered by mixing forests, only small differences presented in simulated meteorological fields, including wind fields, moisture, cloud water mixing ratio, precipitation, and other fields; when covered by bare soil, the latent heating was more important in influencing the process of thunderstorm. There were less latent heating and lower accumulated water vapor compared to other experiments, causing vertical lifting weakening, stability of atmosphere increasing, and precipitation decreasing. [ABSTRACT FROM AUTHOR]

The central role of protein kinases in controlling disease processes has spurred efforts to develop pharmaceutical regulators of their activity. A rational strategy to achieve this end is to determine intrinsic auto-regulatory processes, then selectively target these different states of kinases to repress their activation. Here we investigate auto-regulation of the innate immune effector protein kinase R, which phosphorylates the eukaryotic initiation factor 2α to inhibit global protein translation. We demonstrate that protein kinase R activity is controlled by auto-inhibition via an intra-molecular interaction. Part of this mechanism of control had previously been reported, but was then controverted. We account for the discrepancy and extend our understanding of the auto-inhibitory mechanism by identifying that auto-inhibition is paradoxically instigated by incipient auto-phosphorylation. Phosphor-residues at the amino-terminus instigate an intra-molecular interaction that enlists both of the N-terminal RNA-binding motifs of the protein with separate surfaces of the C-terminal kinase domain, to co-operatively inhibit kinase activation. These findings identify an innovative mechanism to control kinase activity, providing insight for strategies to better regulate kinase activity. [ABSTRACT FROM AUTHOR]