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Novel bamboo activated carbon (BAC) catalysts decorated with manganese oxides (MnOx) were prepared with varying MnOx contents through a facile one-step redox reaction. Due to the physical anchoring effect of the natural macropore structure for catalyst active components, homogeneous MnOx nanoparticles (NPs), and high specific surface area over catalyst surface, the BAC@MnOx-N (N = 1, 2, 3, 4, 5) catalyst shows encouraging adsorption and catalytic oxidation for indoor formaldehyde (HCHO) removal at room temperature. Dynamic adsorption and catalytic activity experiments were conducted. The higher Smicro (733 m2/g) and Vmicro/Vt (82.6%) of the BAC@MnOx-4 catalyst could facilitate its excellent saturated and breakthrough adsorption capacity (5.24 ± 0.42 mg/g, 2.43 ± 0.22 mg/g). The best performer against 2 ppm HCHO is BAC@MnOx-4 catalyst, exhibiting a maximum HCHO removal efficiency of 97% for 17 h without any deactivation as RH = 0, which is higher than those of other MnOx-based catalysts. The average oxidation state and in situ DRIFTS analysis reveal that abundant oxygen vacancies on the BAC@MnOx-4 catalyst could be identified as surface-active sites of decomposing HCHO into the intermediate species (dioxymethylene and formate). This study provides a potential approach to deposit MnOx nanoparticles onto the BAC surface, and this hybrid BAC@MnOx material is promising for indoor HCHO removal at room temperature.
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Mate-choice copying occurs when people rely on the mate choices of others (social information) to inform their own mate decisions. The present study investigated women's strategic trade-off between such social learning and using the personal information of a potential mate. We conducted two experiments to investigate how mate-choice copying was affected by the personal information (e.g., trait/financial information, negative/positive valence of this information, and attractiveness) of a potential male mate in short-/long-term mate selection. The results demonstrated that when women had no trait/financial information other than photos of potential mates, they showed mate-choice copying, but when women obtained personality trait or financial situation information (no matter negative or positive) of a potential mate, their mate-choice copying disappeared; this effect was only observed for low-attractiveness and long-term potential partners. These results demonstrated human social learning strategies in mate selection through a trade-off between social information and personal information.
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Casamento , Aprendizado Social , Comportamento de Escolha , Feminino , Humanos , Masculino , ReproduçãoRESUMO
MAIN CONCLUSION: Both G units and S units deposited in the whole lignification process of xylem fiber. The topochemical variations in newly formed xylem and phloem of Populus × euramericana were investigated by combined microscopic techniques. During xylem formation, earlier cell wall deposition in vessel and afterwards in the neighboring fiber was observed in situ. Raman images in xylem fiber emphasized that cell wall deposition was an ordered process which lignification started in cell corner following carbohydrates deposition. Higher deposition speed of carbohydrates was revealed at the beginning of the cell wall differentiation, and the syringyl (S) units deposition was more pronounced compared with guaiacyl (G) units at the earlier stage of lignification. The comparative analysis of cell wall composition in phloem fiber indicated that phloem formed earlier than xylem and the distribution of lignin monomers varied significantly with phloem fiber location. Furthermore, an interesting phenomenon was found that the outermost phloem fiber near the periderm displayed a multilayered structure with alternating broad and narrow layer, and the broad lamellae showed higher concentration of carbohydrates and S lignin. The cytological information including cell wall composition and lignin structure of xylem and phloem might be helpful to understand the wood growth progresses and facilitate utilization of woody plants.
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Parede Celular/química , Floema/citologia , Populus/citologia , Xilema/citologia , Metabolismo dos Carboidratos , Carboidratos/análise , Parede Celular/metabolismo , Celulose/análise , Lignina/análise , Microscopia de Fluorescência , Microscopia de Polarização , Polímeros/análise , Análise Espectral Raman , Xilema/crescimento & desenvolvimentoRESUMO
As the skeleton substances of lignocellulosic biomass cell wall and the precursor of biofuels production, the research on cellulose structure, an important natural biomarcromolecules, attracts great attention. Considering its in situ features and higher resolution, Raman spectroscopy has been used to investigate the structure of cellulose molecular chain and cellulose aggregation structure at multi-scale. In this paper, the configurations and corresponding parameters of two types of Raman spectroscopy (Dispersive Raman and FT-Raman) were compared. Subsequently, the utilization of Raman spectroscopy in cellulose micro-distribution, cellulose enzyme hydrolysis, cellulose chain orientation and deformation, cellulose crystallinity and polymorphic transformation was discussed in detail. Given the existing deficiencies of the Raman spectroscopy when used to investigate the natural cellulose, some suggestions were proposed in order to promote the application of Raman spectroscopy to the research of natural macromolecular.
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Density, which is closely relate with many physical and mechanical properties of bamboo, is one of the important indicators of bamboo material properties. Moreover, because of existing different moisture gradients in bamboo, the measured results of the density are different. Based on X-ray computed tomography (X-CT) technology, the divergent degree of the CT values of 7 different aged Moso bamboo was compared under oven-dried, air-dried and water-saturated conditions. Except for the 4-year-old and 10-year-old Moso bamboo, the CT values of other aged bamboos have minor differences with each other; the models for the measured CT values and the corresponding densities of Moso bamboo were respectively fitted under oven-dried, air-dried and water-saturated conditions. Meanwhile, the model was also fitted under different moisture gradients, which was composed by the measured CT values and the corresponding densities of Moso bamboo. Then the relations between the CT values andthe densitiesof 7 different aged Moso bamboo were systematically analyzed under single moisture content and three moisture gradients;the CT values were fitted under oven-dried condition, of which the radial positions are relative to the outer of Moso bamboo. According to the relation between the CT value and the density, the fitting curves explain the reasons for the radial density variations of 7 different aged Moso bamboo. Results show that the relations, which are fitted by the measured densities and the corresponding CT values of 7 different aged Moso bamboo under oven-dried, air-dried and water-saturated conditions, are good linear and the slopes of those models are approximate; the relation of the densities with the CT values for Moso bamboo is linear under different moisture gradients, moreover, which is rarely affected by moisture. The regression equation is: D=0.001 H+1.003 2, R2=0.968 3(D is the density, H is the CT value) and the determination coefficient of the validation model is: R2=0.974 3; there is no obvious variation between the densities of the inner and the outer, but not in middle part to 7 different aged Moso bamboo under oven-dried condition. To realize rapid detection on the densities of Moso bamboo under different moisture content, these results provide technical support and data reference. At the same time, X-ray computed tomography (X-CT) technology also puts forward a new feasible way for the further studies of bamboo material properties and structure.
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Structural organization of the plant cell wall is a key parameter for understanding anisotropic plant growth and mechanical behavior. Four imaging platforms were used to investigate the cell wall architecture of Miscanthus sinensis cv. internode tissue. Using transmission electron microscopy with potassium permanganate, we found a great degree of inhomogeneity in the layering structure (4-9 layers) of the sclerenchymatic fiber (Sf). However, the xylem vessel showed a single layer. Atomic force microscopy images revealed that the cellulose microfibrils (Mfs) deposited in the primary wall of the protoxylem vessel (Pxv) were disordered, while the secondary wall was composed of Mfs oriented in parallel in the cross and longitudinal section. Furthermore, Raman spectroscopy images indicated no variation in the Mf orientation of Pxv and the Mfs in Pxv were oriented more perpendicular to the cell axis than that of Sfs. Based on the integrated results, we have proposed an architectural model of Pxv composed of two layers: an outermost primary wall composed of a meshwork of Mfs and inner secondary wall containing parallel Mfs. This proposed model will support future ultrastructural analysis of plant cell walls in heterogeneous tissues, an area of increasing scientific interest particularly for liquid biofuel processing.
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Parede Celular/química , Parede Celular/ultraestrutura , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Transmissão/métodos , Poaceae/química , Poaceae/ultraestrutura , Análise Espectral Raman/métodos , Celulose/análise , Celulose/ultraestrutura , Microfibrilas/química , Microfibrilas/ultraestruturaRESUMO
The wood property and production process affect quality of Guqin. At the same time, Guqin shape with cavity layout relations to the improvement of Guqin technology and inheritance, so it's very important to get the internal cavity characteristics and parameters on the condition of non-destructive the structure of Guqin. The image of interior structure in Guqin was investigated by overall scanning based on non-destructive testing technology of computed tomography, which texture of faceplate, connection method between faceplate and soleplate and interior defects were studied. The three-dimensional reconstruction of Guqin cavity was achieved through Mimics software of surface rendering method and put the two-dimensional CT tomography images convert into three-dimensional, which more complete show interior structural form in Guqin, and finally the parameter of cavity dimensions was obtained. Experimental research shows that there is significant difference in Guqin interior structure between Zhong-ni and Luo-xia type, in which the fluctuation of the interior surfacein Zhong-ni type's is larger than that in Luo-xia type; the interior volume of Zhong-ni typeis less than that of Luo-xia type, especially in Guqin neck. The accurate internal information of Guqin obtained through the computed tomography (CT) technology will provide technical support for the Guqin manufacture craft and the quality examination, as well as provide the reference in the aspect of non-destructive testing for other traditional precious internal structure research.
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X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus fari- X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus farinosus. The results show that there is little variation in MFA with bamboo age from 2a to 5e, and MFA of 3a is at the maximum with the value of 8.521 degrees. The average value of MFA of 2a or 3a is greater than 4a or 5a with absolute differences less than 0.10 degrees. MFA of base, middle and upper position respectively are 8.499 degrees, 8.497 degrees and 8.483 degrees with coefficient of variation about 5%. There is an increasing tendency from the periphery to the inner of bamboo culms. Variance analysis indicates that MFA is highly sensitive to radial position, but insensitive to bamboo age and longitudinal position. The correlation coefficient of longitudinal strength and modulus of elasticity (MOE) is 0.57. MFA was responsible for 35% and 43% of the variation found in longitudinal strength and MOE respectively, which means MFA has a certain extent effect on mechanical properties.
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Microfibrilas/fisiologia , Poaceae/anatomia & histologia , Difração de Raios X , Análise de Variância , Resistência à TraçãoRESUMO
Density is one of the important physical indicators of bamboo, associated with its many physical and mechanical properties. The temporal and spatial variation of density in 2-5-year-old Dendrocalamus farinosus were measured using computed tomography (CT) technology. Scanning parameters were obtained through orthogonal design. The relationship of air-dry density (Y) and the corresponding CT values (X) was established and verified through regression analysis, which presents an approximate linear relationship between them. The linear equation is Y=0.001X+1.148. The radial and longitudinal variation of density was determined by the regression model. This study provides a new method to measure bamboo density efficiently and accurately, and also put forward a new thought to further study structure and characteristics of bamboo.
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Poaceae/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X , Modelos Teóricos , Análise de Regressão , Análise Espaço-TemporalRESUMO
The relationship between oxygen sensing and autophagy in human sperms was explored in this study. Health semen and asthenozoospermia (astheno) semen were incubated with hypoxia-inducible factor-1α (HIF-1α) interferents, i.e., lificiguat (YC-1) or cobalt chloride (CoCl2), respectively. Label-free quantitative proteomic technology was used to identify the differentially expressed proteins in human semen under the hypoxia condition. Selected proteins were detected with ELISA. It was found that the autophagy levels of sperm in the YC-1 + health group or CoCl2 + astheno group increased while the vitality decreased. A total of 17, 34 and 35 differentially expressed proteins were observed in the Astheno group, the YC-1 + health group and the CoCl2 + astheno group, respectively. These proteins were primarily associated with protein processing in endoplasmic reticulum, Th17 cell differentiation, progesterone-mediated oocyte maturation, glycolysis/gluconeogenesis, HIF-1 signaling pathway, biosynthesis of amino acids, and carbon metabolism. The expression levels of protein HIF-1α, LC3B, histone H4, cathepsin L and ENO1 changed significantly in the groups. The study suggests that hypoxia can increase sperm autophagy level and reduce their vitality through HIF-1 signaling pathway and glycolysis/gluconeogenesis signaling pathway. Furthermore, proteins histone H4, cathepsin L, glutathione synthetase and ENO1 are proposed as potential biomarkers of autophagy and vitality in asthenozoospermia sperm.
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Astenozoospermia , Histonas , Humanos , Masculino , Catepsina L , Hipóxia Celular , Proteômica , Sêmen , Hipóxia , Cobalto , Autofagia , Espermatozoides , Subunidade alfa do Fator 1 Induzível por HipóxiaRESUMO
Quantitatively and selectively detecting the biomarker of hydrogen sulfide (H2S) in arthritis diseases is of great significance for the early diagnosis and treatment of arthritis. Modern medical studies show that H2S as a biomarker is involved in the development of inflammation. In this work, a new highly specific fluorescence "turn-on" probe JMD-H2S was tailored for H2S detection and imaging in drug-induced live cells, zebrafish and mice arthritis models, which utilized pyrazoline molecule as the fluorescence signal reporter group and 2,4-dinitrophenyl ether group (DNB) with strong intramolecular charge transfer (ICT) effect as the H2S recognition moiety and fluorescence quenching group. JMD-H2S showed a fast response time (<60 s), a large fluorescence response ratio (enhanced â¼20 folds) at I453/I0, excellent sensitivity toward H2S over other analytes, and an outstanding limit of detection (LOD) as low as 25.3 nM. In addition, JMD-H2S has been successfully applied for detecting and imaging H2S in drug-induced live cells, zebrafish, and mice arthritis models with satisfactory results, suggesting it can be used as a robust molecular tool for investigating the occurrence and development of H2S and arthritis.
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Mixed emotions have attracted increasing interest recently, but existing datasets rarely focus on mixed emotion recognition from multimodal signals, hindering the affective computing of mixed emotions. On this basis, we present a multimodal dataset with four kinds of signals recorded while watching mixed and non-mixed emotion videos. To ensure effective emotion induction, we first implemented a rule-based video filtering step to select the videos that could elicit stronger positive, negative, and mixed emotions. Then, an experiment with 80 participants was conducted, in which the data of EEG, GSR, PPG, and frontal face videos were recorded while they watched the selected video clips. We also recorded the subjective emotional rating on PANAS, VAD, and amusement-disgust dimensions. In total, the dataset consists of multimodal signal data and self-assessment data from 73 participants. We also present technical validations for emotion induction and mixed emotion classification from physiological signals and face videos. The average accuracy of the 3-class classification (i.e., positive, negative, and mixed) can reach 80.96% when using SVM and features from all modalities, which indicates the possibility of identifying mixed emotional states.
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Emoções , Humanos , Eletroencefalografia , Expressão Facial , Gravação em VídeoRESUMO
BACKGROUND/AIMS: To investigate the effects of K-ras siRNA on pancreatic cancer cells and the expression levels of GLI1, E-cadherin and vimentin in pancreatic cancer cells transfected with K-ras siRNA. METHODOLOGY: Ppancreatic cancer cells PANC-1 were transfected with K-ras siRNA. Growth inhibition ratio of the cells were measured by MTT assay, apoptosis was detected by flow cytometery, expression level of GLI1, E-cadherin and vimentin were detected by Western blot. RESULTS: The expression of K-ras protein was efficiently inhibited by K-ras siRNA in PANC-1 cells. The growth inhibition rates of the cells were significantly different to the control groups. Apoptosis rates were significantly different with that of control group. The expression of GLI1 was significantly down-regulated, E-cadherin was up-regulated, while vimentin was also down-regulated in K-ras siRNA transfected cells compared with that of control groups. CONCLUSIONS: Inhibiting K-ras signaling by K-ras siRNA can inhibit proliferation and induce apoptosis of pancreatic cancer cells, down-regulate GLI1's and vimentin's expression, and up-regulate E-cadherin's expression. Inhibiting K-ras signaling by K-ras siRNA may reduce epithelial to mesenchymal transition of pancreatic cancer cell PANC-1.
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Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Proteínas ras/fisiologia , Apoptose , Caderinas/análise , Linhagem Celular Tumoral , Humanos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras) , Vimentina/análise , Proteínas ras/antagonistas & inibidoresRESUMO
Global energy concerns urged us to search for sufficient utilization of biomass to renewable energy. Herein, rattan biomass displaying herbaceous species-like anatomy and hardwood-like chemical composition was used as model of lignocellulose to determine its recalcitrance inhibiting efficient bioconversion. Delignification and continuous mild alkaline treatments were applied for deconstruction of rattan cane (Calamus simplicifolius) followed by cellulase enzymatic hydrolysis. Cellulose supramolecular structural variations were proved to be the major reason for the enhanced hydrolysis in addition to the removal of lignin and hemicelluloses matrix. Lowered crystallinity (50-65 %) as well as swelled crystallite sizes (4.8-5.0 nm) during allomorphic transformation favored the enhanced hydrolysis, rather than the crystalline cellulose II. Moreover, well-distributed separation and fibrillation of cellulose elementary fibrils also contributed to glucose yield promotion. The study will provide new insights to the strategy to efficient bioconversion of lignocellulosic biomass.
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Celulase , Celulose , Celulose/química , Biomassa , Lignina/química , Glucose/química , Biocombustíveis , HidróliseRESUMO
The precursor compound plays a crucial role in the development of low-cost chalcogenide thin-film solar cells via a solution approach. In this work, we report on the synthesis of a new complex [Cu((NH2)2CS)3]2SO4·H2O through a simple redox reaction between inexpensive Cu(CH3COO)2·H2O and thiourea (TU) in water. Using this complex as a copper source, a stable dimethylformamide solution was made and copper indium sulfoselenide CuIn(S,Se)2 thin film solar cells with a high efficiency of 12.2% have been demonstrated.
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Bamboo is a natural vascular bundle (VB) reinforced composite material used in more than 10 fields such as construction and furniture. The nodes in bamboo are crucial to its mechanical properties, but understanding of its performance is limited by lack of knowledge about the three-dimensional (3D) structure of the node. This work aimed to non-destructively identify the multi-dimensional characteristics of the VB in a bamboo branched node (BN) using X-ray microtomography (µCT). The VB was segmented from the BN using deep learning combined with the Watershed algorithm. The 3D model reconstruction and characterization of the VB were also conducted. It was found that the structure of VBs showed significant changes along the height of the BN. The VBs formed a complex 3D structure, VBs of the culm are connected with those of the branch, and the connectivity of the conducting tissue and fibers was 88.91% and 99.95%, respectively. The conducting tissue and the fibers had similar shapes but varying thicknesses, which enabled VBs to perform both water transport and mechanical support functions. The volumes fraction of parenchyma, fibers, and conducting tissue in the BN were 61.3%, 35.3%, and 3.4%, respectively, but the tissue proportion of the different heights of the BN varied from each other. The nodal ridge was a mechanical weak point of the BN, with a maximum fibers proportion of 43.8%. This study contributes to understanding the relationship of VBs between the branch and the culm. It provides a structural perspective for understanding the mechanical properties of BN and a theoretical basis for optimizing bamboo utilization efficiency.
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CT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry density (0.303-1.061 g x cm(-3)) of 24 kinds of woods and their respective CT value, as well as 25 kinds of lignin materials (including 24 kinds of woods and 1 kind of bamboo) and the CT value, both with correlation coefficient of 0.99, which belonged to the CT technological breakthrough for wood quantitative detection These research results show that CT is an appropriate way to measure density for wood and bamboo, and would provide technical support for CT used in the field of wood science research and wood processing.
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Bambusa , Tomografia Computadorizada por Raios X , Madeira , LigninaRESUMO
As a renewable biological macromolecule with aromatic structure, lignin can serve as matrix substance to maintain cell wall integrity and is regarded as the natural biomass recalcitrance. Substantial differences in the cell wall lignin topochemistry between opposite (Ow) and compression wood (Cw) trachieds in Pinus bungeana Zucc. were visualized during [Emim][OAc] pretreatment at room temperature. The ionic liqiuds treatment induced a more obvious wall swelling for highly lignified Cw tracheids than that of Ow, while dynamic Raman spectra analysis indicated the higher lignin and carbohydrates removal for Ow tracheids. Raman imaging further revealed that both lignin and carbohydrates were dissolved simultaneously within the middle lamella and secondary wall of Ow and pretreatment has little effects on Cw tracheids wall. Moreover, it was demonstrated that lignin composition was the key factor to affect the composition dissolution. In particular, lignin G-units were selectively removed from cell corner middle lamella (52.3 %) and secondary wall (62.0 %) of Ow tracheids. When cotton fiber, as a reference was treated under the same conditions, lattice conversion moving from cellulose I to II occurred. The findings confirmed the important role of lignin compostion in the dissolution behavior of carbohydrate dominant tracheids wall.
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Pinus , Madeira , Madeira/química , Lignina/química , Solubilidade , Pinus/química , Parede Celular/química , Celulose/químicaRESUMO
The morphological characteristics of fibers and vessels of six rattan species in Southern China were investigated to study the feasibility of predicting the lengths of fibers and vessels of rattan species with application of analytical technologies of near infrared spectroscopy (NIR). The results showed that the average lengths of fibers and vessels of six rattan species were from 1 229 to 1 917 mm and from 1 035 to 2 129 mm, respectively. The models of length of fiber and vessel were constructed by combining partial least square (PLS) and full cross-validation, and a good correlation between the length of fibers and the spectrum transformed by the first derivative was found within the spectral range of 350 - 2 454 nm, and the correlation coefficient (r(c) and r(p)) and standard error (SEC and SEP ) of calibration model and prediction model are 0.98, 0.85 and 70, 178 respectively, while a good correlation between the length of vessels and the spectrum transformed by the first derivative was found within the spectral range of 350-2 500 nm, the correlation coefficient (r(c) and r(p)) and standard error (SEC and SEP) of calibration and prediction model is 0.97, 0.80 and 101, 261 respectively. Their model parameters showed that NIR spectroscopic technique can rapidly and accurately predict the lengths of fibers and vessels of the six rattan species.
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Calamus , Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , China , Análise dos Mínimos QuadradosRESUMO
It has been well documented that static face processing is holistic. Faces contain variant (e.g., motion, viewpoint) and invariant (race, sex) features. However, little research has focused on whether holistic face representations are tolerant of within-person variations. The present study thus investigated whether holistic face representations of faces are tolerant of within-person motion and viewpoint variations by manipulating study-test consistency using a complete composite paradigm. Participants were shown two faces sequentially and were asked to judge whether the faces' top halves were identical or different. The first face was a static face or a dynamic face rotated in depth at 30°, 60°, and 90°. The second face was either a different front-view static face (Experiment 1a, study-test inconsistent) or identical to the first face (Experiment 1b, study-test consistent). In Experiment 2, study-test consistency was manipulated within subjects, and inverted faces were included. Our results show that study-test consistency significantly enhanced the holistic processing of upright and inverted faces; this study-test consistency effect and holistic processing were not modulated by motion and viewpoint changes via depth rotation. Interestingly, we found holistic processing for moving study-test consistent inverted faces, but not for static inverted faces. What these results tell us about the nature of holistic face representation is discussed in depth with respect to earlier and current theories on face processing.