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With the rapid development of artificial intelligence technology, data-driven advanced models have provided new ideas and means for airfoil aerodynamic optimization. As the advanced models update and iterate, many useful explorations and attempts have been made by researchers on the integrated application of artificial intelligence and airfoil aerodynamic optimization. In this paper, many critical aerodynamic optimization steps where data-driven advanced models are employed are reviewed. These steps include geometric parameterization, aerodynamic solving and performance evaluation, and model optimization. In this way, the improvements in the airfoil aerodynamic optimization area led by data-driven advanced models are introduced. These improvements involve more accurate global description of airfoil, faster prediction of aerodynamic performance, and more intelligent optimization modeling. Finally, the challenges and prospect of applying data-driven advanced models to aerodynamic optimization are discussed. [ABSTRACT FROM AUTHOR]

In this research, we introduce a deep-learning-based framework designed for the prediction of transonic flow through a linear cascade utilizing large-scale point-cloud data. In our experimental cases, the predictions demonstrate a nearly four-fold speed improvement compared to traditional CFD calculations while maintaining a commendable level of accuracy. Taking advantage of a multilayer graph structure, the framework can extract both global and local information from the cascade flow field simultaneously and present prediction over unstructured data. In line with the results obtained from the test datasets, we conducted an in-depth analysis of the geometric attributes of the cascades reconstructed using our framework, considering adjustments made to the geometric information of the point cloud. We fine-tuned the input using 1603 data points and quantified the contribution of each point. The outcomes reveal that variations in the suction side of the cascade have a significantly more substantial influence on the field results compared to the pressure side and explain the way graph neural networks work for cascade flow-field prediction, enhancing the comprehension of graph-based flow-field prediction among developers and proves the potential of graph neural networks in flow-field prediction on large-scale point clouds and design. [ABSTRACT FROM AUTHOR]

Electrorheological (ER) fluid, as an intelligent material, is a kind of suspension composed of polarized micro‐ and/or nanoparticles dispersed into insulating oil. In recent years, molybdenum disulfide (MoS2), as the hottest 2D material, has provided a new strategy to develop the high‐performance ER materials. 2D‐based ER composites can provide large surface to enhance the polarization. But the MoS2 ER material has many disadvantages such as low polarization strength and high electrical conductivity. To make up these defects, polyaniline (PANI) is used to combine with lamellar MoS2. Herein, PANI and MoS2 hybrid composite nanoparticles with special morphology are prepared by two‐step method. The coating material has special morphology, high interfacial polarization, specific surface area, and low density. The optimum reaction ratio is obtained by adjusting the proportion of MoS2 and PANI. When the proportion of PANI and MoS2 is 4:1, the material performance is best, in which the shear stresses can reach 150 Pa. In a word, it is proved that the material is an excellent electrorheological material. [ABSTRACT FROM AUTHOR]

As a core component of an aero-engine, the aerodynamic performance of the nacelle is essential for the overall performance of an aircraft. However, the direct design of a three-dimensional (3D) nacelle is limited by the complex design space consisting of different cross-section profiles and irregular circumferential curves. The deep manifold learning-assisted geometric multiple dimensionality reduction method combines autoencoders (AE) with strong capabilities for non-linear data dimensionality reduction and class function/shape function transformation (CST). A novel geometric dimensionality reduction method is developed to address the typical constraints of nacelle parameterization. Low-dimensional latent variables are extracted from the high-dimensional design space to achieve a parametric representation of 3D nacelle manifolds. Compared with traditional parametric methods, the proposed geometric dimensionality reduction method improves the accuracy and efficiency of geometric reconstruction and aerodynamic evaluation. A multi-objective optimization framework is proposed based on deep manifold learning to increase the efficiency of 3D nacelle design. The Pareto front curves under drag divergence constraints reveal the correlation between the geometry distribution and the surface isentropic Mach number distribution of 3D nacelles. This paper demonstrates the feasibility of the proposed geometric dimensionality reduction method for direct multi-objective optimization of 3D nacelles. [ABSTRACT FROM AUTHOR]

In this paper, the effects of citric acid (CA) and protein retarder (SC) on the properties of phosphogypsumsulfoaluminate cement composite cementitious system were investigated. The fluidity, setting time and compressive strength were tested to evaluate the workability and mechanical of composite system, and the change of conductivity, phase composition and microstructure were analyzed to clarify the influence mechanism of different retarders. The results show that the strength loss of composite cementitious system under the action of SC is smaller than that of CA when the same setting time is achieved. The addition of two retarders has a certain inhibitory effect on the dissolution of composite system during the hydration induction and the acceleration period, and CA has a greater inhibitory effect than SC at the same content. CA can cause gypsum dihydrate crystals to show a flat and coarse structure, which has a greater impact on the mechanical properties, while SC increases the overall scale of gypsum dihydrate crystals, with little change in crystal morphology, which has a smaller effect on the deterioration of the mechanical properties of composite system. [ABSTRACT FROM AUTHOR]

Objective: This study aims to evaluate the efficacy and safety of spinal cord stimulation (SCS) compared to conventional medical management (CMM) for patients diagnosed with chronic pain. Furthermore, the study seeks to compare the utilization of analgesics, as well as the long-term outcomes in terms of quality of life and functional capacity. Data sources: We systematically searched Cochrane Library, Web of Science, PubMed, and EMBASE for randomized controlled trials from inception up to February 2022. Review methods: Inclusion and exclusion criteria were set according to the PICOS criteria. We searched for studies in which SCS was compared with CMM alone for chronic pain. Two reviewers independently identified eligible studies and extracted data. Risk of bias assessments were performed according to Cochrane review criteria and Interventional Pain Management Techniques–quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) criteria. Results: The present meta-analysis comprised eight studies and included a total of 893 patients. Our findings demonstrate that spinal cord stimulation (SCS) in combination with conventional medical management (CMM) is associated with a significant reduction in visual analogue scale (VAS) pain intensity (P = 0.0005) and decreased scores on the McGill Pain Questionnaire (MPQ) (P < 0.0001). Moreover, SCS plus CMM was found to improve patients' quality of life, as evidenced by improvements in SF-36 scores (P < 0.00001), EQ-5D utility index (P = 0.008), and Oswestry Disability Index (ODI) (P < 0.00001). Based on the results of four high-quality randomized controlled trials (RCTs), the level of evidence supporting the efficacy of SCS for the treatment of painful neuropathy is graded as level I to II. In contrast, there is currently only low-level evidence to support the use of high-frequency stimulation and other chronic pain conditions, which can be attributed to a lack of sufficient randomized controlled trials. Limitations: The principal limitation of our study is the significant heterogeneity observed among the cohorts investigated. The primary source of this heterogeneity is the fact that spinal cord stimulation is indicated for the treatment of multiple chronic pain conditions. Moreover, variations in the stimulation parameters, differences among manufacturers, and the specific surgical implantation settings contribute to the increased heterogeneity observed in our analyses. To address this issue, we conducted a subgroup analysis based on specific situations and performed evidence synthesis to mitigate the potential impact of heterogeneity. These approaches allow for a more precise interpretation of the results and a more accurate evaluation of the quality of the included studies. Conclusions: SCS is an effective treatment to relieve the pain level of chronic pain, decrease analgesic usage, and increase long-term quality of life and functional capacity. [ABSTRACT FROM AUTHOR]

Conventional approaches of design variable generation in nacelle design cases are usually proposed from either of two perspectives: (1) utilizing geometric resemblance to airfoil shape; or (2) selecting flexible geometric parametrization so that any potential geometry can be produced. However, the relationship between geometry and aerodynamic performance objectives is not emphasized in these approaches: design variables are likely not carrying the information that is most needed for aerodynamic optimization, as is the case in nacelle cowl design of drag reduction. In fact, an ideal aerodynamic information should be related with the move of samples toward better aerodynamic performance in design space. As an attempt to fix this issue, this paper proposes a new design variable generation method by extracting objective space (i.e., the aerodynamic performance of samples mapped from nacelle design space) information via linear discriminant analysis (LDA). By accomplishing this "objective space filtration," the aerodynamic performance improvement potential is injected into design variable generation. Proof-of-concept studies of nacelle cowl design are provided in the paper demonstrating a more direct relationship that links: (1) LDA-aided design variables versus cowl drag, and (2) LDA-aided design variables versus shock strength and laminar length, respectively. LDA is used in the studies as a classic technique of classification, so that the analysis of objective space information finds a way to have impact on design space. The new approach outperforms a controlled test realized by Proper Orthogonal Decomposition in terms of reflecting aerodynamic information in design space, in that a localized improvement of aerodynamic objectives can be more clearly seen in the newly generated design variables. The result shows that the new design variable generation helps improve aerodynamic design and that it can be further extended to other cases beyond the scope of nacelle cowl design. [ABSTRACT FROM AUTHOR]

In this paper, a new aerodynamic solution strategy for non-smooth configurations is proposed based on the wall modification model by machine learning to perform numerical simulations, rather than directly describing the global flow field with massive grids. The aerodynamic effect of non-smooth configurations in the presence of pressure gradients is investigated utilizing the proposed method. Flow features of non-smooth surface are provided by high-fidelity surface flow data acquired through lattice Boltzmann method simulation. The wall modification model is constructed by Fruit fly Optimization Algorithm-Generalized Regression Neural Network (FOA-GRNN) to reproduce the behavior of microflow near the non-smooth surface. Typical flow features, e.g., velocity corrections induced by surface texture as the output of the FOA-GRNN model, are imposed on configuration boundaries, improving computational efficiency and wall resolution. The novel aerodynamic solution strategy is validated by comparing the results of the experiment. In addition, the performance analysis of compressor cascade with micro riblet surface utilizing the above method is conducted. The results indicate that the non-smooth surface structure decreases skin friction and turbulent intensity in the flow channel compared with smooth cascade, thus significantly reducing the total pressure loss. The paper shows a positive prospect of the data-driven strategy in evaluating the aerodynamic performances of non-smooth configurations and provides a reliable solution method for the subsequent design of micro-nano surfaces. [ABSTRACT FROM AUTHOR]

Due to the harsh operating environment of aero-engines, a surface structure that provides excellent aerodynamic performance is urgently required to save energy and reduce emissions. In this study, microgroove polyurethane coatings fabricated by chemical synthesis are investigated in terms of their effect on aerodynamic performance, which is a new attempt to investigate the impact on aerodynamic performance of compressor cascade at transonic speeds. This method reduces manufacturing and maintenance cost significantly compared with traditional laser machining. Wake measurements are conducted in the high-speed linear compressor cascade wind tunnel to evaluate the performance of cascade attached with different microgroove polyurethane coatings. Compared with the Blank case, the microgroove polyurethane coatings have the characteristic of reducing flow loss, with a maximum reducing rate of 5.87% in the area-averaged total pressure loss coefficient. The mechanism of flow loss control is discussed through analyzing the correlation between the total pressure distribution and turbulence intensity distribution. The results indicate that a large quantity of energy loss in the flow field due to turbulence dissipation and the reduction in viscous drag by microgroove polyurethane coatings relates to its effect on turbulence control. This paper demonstrates a great perspective on designing micro-nano surface structure for aero-engine applications. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries represent one of the most common causes of permanent disabilities. Therapeutic electrical stimulation has been widely used in neural regeneration for decades. Combined with the implantation of a nerve cuff, several outcomes have proven effectiveness and feasibility in neuroprosthetic applications. However, the current electrical stimulation strategy fails to complete nerve repair. There is a lack of research on long‐term implantable nanogenerators in the neurostimulation scenario. Especially considering many disease models, those devices may not reach the in vitro simulative working setting. Thus, an implanted sciatic nerve stimulation system that spontaneously generates biphasic electric pulses in response to rats' movement is developed. The electric signals generated by this device could stimulate injured sciatic nerve by cuff electrode. This work introduces an implantable self‐regulated neural electrical stimulation system generated by a contact separation triboelectric nanogenerator with a nerve cuff electrode and compares it with chronic therapeutic electrical stimulation for sciatic nerve restoration effect. Neural function restoration is observed in gait and histological analysis. Moreover, the upregulation of growth associated protein 43 can be a protentional target. This could have potential clinical application in facilitating closed‐loop energy harvesting for long‐term electrical stimulation. [ABSTRACT FROM AUTHOR]

Background: Circular RNAs have shown important regulatory roles in cardiovascular diseases, containing atherosclerosis (AS). We intended to explore the role of circ_0004104 in AS using oxidized low-density lipoprotein (ox-LDL)-induced vascular endothelial cells and its associated mechanism.Methods: Real-time quantitative polymerase chain reaction and Western blot assay were conducted to analyze RNA levels and protein levels, respectively. Cell viability, apoptosis, angiogenic ability and inflammatory response were assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay, flow cytometry, capillary-like network formation assay and enzyme-linked immunosorbent assay, respectively. Cell oxidative stress was assessed using commercial kits. Dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA-pull down assay were performed to verify the intermolecular interaction.Results: ox-LDL exposure up-regulated the level of circ_0004104 in HUVECs. ox-LDL exposure suppressed cell viability and angiogenic ability whereas promoted the apoptosis, inflammation and oxidative stress of HUVECs partly through up-regulating circ_0004104. MicroRNA-328-3p (miR-328-3p) was confirmed as a target of circ_0004104. MiR-328-3p interference largely reversed circ_0004104 silencing-mediated effects in HUVECs upon ox-LDL exposure. MiR-328-3p interacted with the 3' untranslated region of tripartite motif 14, and circ_0004104 positively regulated TRIM14 expression by sponging miR-328-3p. TRIM14 overexpression largely overturned miR-328-3p accumulation-induced influences in HUVECs upon ox-LDL exposure.Conclusion: Circ_0004104 knockdown attenuated ox-LDL-induced dysfunction in HUVECs via miR-328-3p-mediated regulation of TRIM14. [ABSTRACT FROM AUTHOR]

The multi-objective optimization of compressor cascade rotor blade is important for aero engine design. Many conventional approaches are thus proposed; however, they lack a methodology for utilizing existing design data/experiences to guide actual design. Therefore, the conventional methods require and consume large computational resources due to their need for large numbers of stochastic cases for determining optimization direction in the design space of problem. This paper proposed a Reinforcement Learning method as a new approach for compressor blade multi-objective optimization. By using Deep Deterministic Policy Gradient (DDPG), the approach modifies the blade profile as an intelligent designer according to the design policy: it learns the design experience of cascade blade as accumulated knowledge from interaction with the computation-based environment; the design policy can thus be updated. The accumulated computational data is therefore transformed into design experience and policies, which are directly applied to the cascade optimization, and the good-performance profiles can be thus approached. In a case study provided in this paper, the proposed approach is applied on a blade profile, which is thus optimized in terms of total pressure loss and laminar flow area. Compared with the initial profile, the total pressure loss coefficient is reduced by 3.59 % , and the relative laminar flow area at the suction surface is improved by 25.4 % . [ABSTRACT FROM AUTHOR]

The treatment methods of asphalt pavement diseases, and the preparation and testing methods of modified asphalt crack paste specimens are introduced. The impact of plasticiser, modifier, tackifier and padding on softening point, low temperature flexibility, peel strength, shear strength and continuous cohesiveness of asphalt/crack paste are discussed respectively, and the results showed that, the addition of plasticizer could improve the performance of asphalt/crack paste. Then a suitable material ratio was obtained in combination of environmental protection and the cost, and the performance of the crack paste prepared according to this ratio were tested. [ABSTRACT FROM AUTHOR]

Background: Salinity has obvious effects on plant growth and crop productivity. The salinity-responsive mechanisms have been well-studied in differentiated organs (e.g., leaves, roots and stems), but not in unorganized cells such as callus. High-throughput quantitative proteomics approaches have been used to investigate callus development, somatic embryogenesis, organogenesis, and stress response in numbers of plant species. However, they have not been applied to callus from monocotyledonous halophyte alkaligrass (Puccinellia tenuifora). Results: The alkaligrass callus growth, viability and membrane integrity were perturbed by 50 mM and 150 mM NaCl treatments. Callus cells accumulated the proline, soluble sugar and glycine betaine for the maintenance of osmotic homeostasis. Importantly, the activities of ROS scavenging enzymes (e.g., SOD, APX, POD, GPX, MDHAR and GR) and antioxidants (e.g., ASA, DHA and GSH) were induced by salinity. The abundance patterns of 55 salt-responsive proteins indicate that salt signal transduction, cytoskeleton, ROS scavenging, energy supply, gene expression, protein synthesis and processing, as well as other basic metabolic processes were altered in callus to cope with the stress. Conclusions: The undifferentiated callus exhibited unique salinity-responsive mechanisms for ROS scavenging and energy supply. Activation of the POD pathway and AsA-GSH cycle was universal in callus and differentiated organs, but salinity-induced SOD pathway and salinity-reduced CAT pathway in callus were different from those in leaves and roots. To cope with salinity, callus mainly relied on glycolysis, but not the TCA cycle, for energy supply. [ABSTRACT FROM AUTHOR]

QiShenYiQi dripping pills (QSYQ), a traditional Chinese medicine, are commonly used to treat coronary heart disease, and QSYQ was recently approved as a complementary treatment for ischemic heart failure in China. However, only few studies reported on whether QSYQ exerts a protective effect on heart failure induced by pressure overload. In this study, we explored the role of QSYQ in a mouse model of heart failure induced by transverse aortic constriction (TAC). Twenty-eight C57BL/6J mice were divided into four groups: Sham + NS group, Sham + QSYQ group, TAC + NS group, and TAC + QSYQ group. QSYQ dissolved in normal saline (NS) was administered intragastrically (3.5mg/100 g/day) in the Sham + QSYQ and TAC + QSYQ groups. In the Sham + NS and TAC+NS groups, NS was provided every day intragastrically. Eight weeks after TAC, echocardiography, and cardiac catheterization were performed to evaluate the cardiac function, and immunofluorescent staining with anti-actinin2 antibody was performed to determine the structure of the myocardial fibers. Moreover, TUNEL staining and Masson trichrome staining were employed to assess the effects of QSYQ on cardiac apoptosis and cardiac fibrosis. Western blots and real-time polymerase chain reaction (PCR) were used to measure the expression levels of vascular endothelial growth factor (VEGF) in the heart, and immunohistochemical staining with anti-CD31 antibody was performed to explore the role of QSYQ in cardiac angiogenesis. Results showed that TAC-induced cardiac dysfunction and disrupted structure of myocardial fibers significantly improved after QSYQ treatment. Moreover, QSYQ treatment also significantly improved cardiac apoptosis and cardiac fibrosis in TAC-induced heart failure, which was accompanied by an increase in VEGF expression levels and maintenance of microvessel density in the heart. In conclusion, QSYQ exerts a protective effect on TAC-induced heart failure, which could be attributed to enhanced cardiac angiogenesis, which is closely related to QSYQ. Thus, QSYQ may be a promising traditional Chinese medicine for the treatment of heart failure induced by pressure overload such as hypertension. [ABSTRACT FROM AUTHOR]

Lithium lanthanum titanate Li0.33La0.56TiO3 with a perovskite structure and Li1.3Al0.3Ti1.7(PO4)3 with a NASICON structure are promising solid lithium-ion conductors. Attrition milling is carried out to alter the particle size and a solid-state reaction method is used to prepare the pellets. The mean volume of Li1.3Al0.3Ti1.7(PO4)3 and Li0.33La0.56TiO3 tends to increase and to decrease, respectively, with increasing attrition milling time, which is due to the different hardness of the starting materials used. When pressed into pellets, the powders with smaller variation in the particle size possess denser packing and, therefore, higher conductivity. The conductivities of lithium-conductors are in strong correlation with the size of the starting powders and the density of the pellets. [ABSTRACT FROM AUTHOR]

Our previous work showed that a plasmid-based chicken interleukin-7 (chIL-7) gene expression vector possessed potent adjuvant activity for a VP2 DNA vaccine against chicken infectious bursal disease virus (IBDV). Whether recombinant chIL-7 prepared in procaryotic expression system has the adjuvant activity for inactivated IBDV vaccine remains unknown. Here, we prepared recombinant chIL-7 using an E. coli expression system and analyzed its adjuvant activity for the inactivated IBDV vaccine. The results show that the recombinant chIL-7 was successfully prepared in E. coli using the pET20b vector, which possessed biological activity to stimulate mouse B lymphocyte proliferation. Co-administration of the chIL-7 with inactivated IBDV vaccine significantly increased specific serum antibody titers against IBDV, enhanced lymphocyte proliferation and IFN-Υ and IL-4 productions and increased protection against virulent IBDV infection. [ABSTRACT FROM AUTHOR]

We analyzed the effects of matrix metalloproteinase (MMP)-1, MMP-3, and MMP-12 on the degree of carotid atherosclerosis (CAS) and plaque stability, and investigated their correlations with cardiovascular and cerebrovascular events (CCEs). Two hundred CAS patients were enrolled. Carotid intima-media thickness (IMT) was measured using ultrasonic examination. Patients were divided into the no plaque group (NP group), stable plaque group (SP group), and vulnerable plaque group (VP group). The Crouse method was used for the evaluation of plaque scores. Additionally, 60 healthy subjects were enrolled as the control group. Serum triacylglycerol (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were analyzed. The serum protein levels of MMP-1, MMP-3, and MMP-12 were measured by western blotting. The frequency of CCEs within 2 years was recorded, and its correlation with MMP-1, MMP-3, and MMP-12 was analyzed. The CAS plaque scores in the SP and VP groups were significantly increased compared with the NP group, and the difference between the SP and VP groups was significant. The levels of TC, TG, LDL-C, and HDL-C of CAS patients were significantly increased compared with those in the control group, but the differences in these indexes between the patient groups were not significant. Western blotting showed that the levels of MMP-1, MMP-3, and MMP-12 in the patient groups were significantly increased compared with those in the control group, and the protein levels in the VP group were significantly higher than those in the SP and NP groups. Additionally, the levels of MMP-1, MMP-3, and MMP-12 had significantly positive correlations with the occurrence of CCEs in CAS patients. In conclusion, MMP-1, MMP-3, and MMP-12 are positively correlated with CCEs in CAS patients. They can be used as markers for the clinical diagnosis and prognosis of CAS. [ABSTRACT FROM AUTHOR]

This study examined the relationship between PDGF-induced proliferation of vascular smooth muscle cells (VSMCs) and Nur77 expression and the effect of atorvastatin on VSMC proliferation and Nur77 in PDGF-treated VSMCs. Rat VSMCs were isolated and cultured. After incubation with atorvastatin or Nur77 siRNA, the cells were stimulated with PDGF and detected for BrdU incorporation to measure the proliferation of the VSMCs. Quantitative PCR and Western blotting were used to determine the Nur77 protein and the CREB phosphorylation level, to observe their relations with PDGF-induced VSMC proliferation. Our results showed that PDGF increased the BrdU incorporation in VSMCs, suggesting that it induced the proliferation of the cells. The VSMC proliferation was associated with increased Nur77 expression and elevated CREB phosphorylation. Atorvastatin inhibited the PDGF-induced VSMC proliferation, suppressed Nur77 expression. After silencing of Nur77 gene, the PDGF-induced VSMC proliferation was decreased. It was concluded that PDGF-induced VSMC proliferation was related to the Nur77 expression and CREB phosphorylation. Atorvastatin reduced the Nur77 expression and, at the same time, inhibited the VSMC proliferation. [ABSTRACT FROM AUTHOR]

It has been reported that Nur77 over-expresses in arteriosclerotic lesions and has both pro- and anti-proliferative effects on vascular smooth muscle cells (VSMCs). We investigated the physiological function of Nur77 on proliferation in VSMCs and the effects of atorvastatin on the expression of Nur77. Platelet-derived growth factor (PDGF), a key growth factor mediating VSMC proliferation in atherogenesis and post-angioplasty restenosis, was employed to induce the transcriptional regulation of Nur77 expression in VSMCs and rat carotid artery post-angioplasty restenosis models were used to investigate the effect of atorvastatin on the expression of Nur77 by immunohistochemistry, RT-PCR, and western blot methods. In cell models, we found that PDGF-B induced Nur77 mRNA expression and protein expression through ERK–MAPK-dependent signaling pathways, and atorvastatin attenuated the expression of Nur77 induced by PDGF-B. In the rat model, our data showed Nur77 was up-regulated in neointima, but down-regulated by atorvastatin. Our results indicate that Nur77 promotes VSMC proliferation, and down-regulation of Nur77 by atorvastatin suggests a novel therapy strategy for atherogenesis based on suppression of VSMC proliferation. [ABSTRACT FROM AUTHOR]